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Measurement, spatial spillover and influencing factors of agricultural carbon emissions efficiency in China
WU Haoyue, HUANG Hanjiao, HE Yu, CHEN Wenkuan
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Effects of tillage and straw returning method on the distribution of carbon and nitrogen in soil aggregates
ZHANG Yuming, HU Chunsheng, CHEN Suying, WANG Yuying, LI Xiaoxin, DONG Wenxu, LIU Xiuping, PEI Lin, ZHANG Hui
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Relationship between policy incentives, ecological cognition, and organic fertilizer application by farmers: Based on a moderated mediation model
SANG Xiance, LUO Xiaofeng, HUANG Yanzhong, TANG Lin
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Spatio-temporal evolution of carbon stocks in the Yellow River Basin based on InVEST and CA-Markov models
YANG Jie, XIE Baopeng, ZHANG Degang
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Effects of straw returning and fertilization on soil bacterial and fungal community structures and diversities in rice-wheat rotation soil
ZHANG Hanlin, BAI Naling, ZHENG Xianqing, LI Shuangxi, ZHANG Juanqin, ZHANG Haiyun, ZHOU Sheng, SUN Huifeng, LYU Weiguang
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2016 Vol. 24, No. 12
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2016, 24(12): 1585-1597.
doi: 10.13930/j.cnki.cjea.160557
Abstract:
Most of the records on interspecific relationship in agriculture and forest ecosystems were conserved during the long agricultural history of China. The interspecific association is divided into competition, facilitation and neutrality, where competition is studied in a greater depth. There was an increasing attention on facilitation introduced by the mainstream ecology theories in the past 20 years. China owns voluminous ancient books in which the historical documents left a whole lot of relevant records concerning relationships among species. The records were ancient and accumulated over a long term in the productive practices of observations and experiences. This paper analyzed the ecological mechanisms of these records, most of which were about seedling shading and soil nutrients improvement using legume nitrogen fixation. There was also a small volume of record on buffering extreme temperature (high temperatures in summer and low temperatures in winter), reducing weed competition, preventing predation and alleviating water stress. There was not only rich records about the utilization of facilitation effect between the two plant species in ancient China, but also on the integrated and complex relationship among several plant species as well as the complex relationships between plants and animals in the ecosystem. This was especially the case for southern China which owned the records on traditional experiences on building complex ecosystem of orchards, tea plantations and other aspects of the ecosystem by the diverse plants and animals. The study sorted and analyzed ancient literatures on plant facilitation effect based on ecological theory. The study hoped to draw more attention on traditional experiences, especially those of ecologists. We hoped that more and more researchers investigate and verify the authenticity and applicability of the records on the basis of the theories of modern ecology and experimental methods to provide more useful references for ecological agriculture and modern forestry.
Most of the records on interspecific relationship in agriculture and forest ecosystems were conserved during the long agricultural history of China. The interspecific association is divided into competition, facilitation and neutrality, where competition is studied in a greater depth. There was an increasing attention on facilitation introduced by the mainstream ecology theories in the past 20 years. China owns voluminous ancient books in which the historical documents left a whole lot of relevant records concerning relationships among species. The records were ancient and accumulated over a long term in the productive practices of observations and experiences. This paper analyzed the ecological mechanisms of these records, most of which were about seedling shading and soil nutrients improvement using legume nitrogen fixation. There was also a small volume of record on buffering extreme temperature (high temperatures in summer and low temperatures in winter), reducing weed competition, preventing predation and alleviating water stress. There was not only rich records about the utilization of facilitation effect between the two plant species in ancient China, but also on the integrated and complex relationship among several plant species as well as the complex relationships between plants and animals in the ecosystem. This was especially the case for southern China which owned the records on traditional experiences on building complex ecosystem of orchards, tea plantations and other aspects of the ecosystem by the diverse plants and animals. The study sorted and analyzed ancient literatures on plant facilitation effect based on ecological theory. The study hoped to draw more attention on traditional experiences, especially those of ecologists. We hoped that more and more researchers investigate and verify the authenticity and applicability of the records on the basis of the theories of modern ecology and experimental methods to provide more useful references for ecological agriculture and modern forestry.
2016, 24(12): 1598-1606.
doi: 10.13930/j.cnki.cjea.160422
Abstract:
Integrated Agri-Aquaculture Systems (IAAS) such as rice-fish farming have been practiced for centuries in China. In these systems, on-farm wastes and by-products are recycled in relatively closed nutrient cycles. IAAS also utilizes resource efficiently and provides additional food and income to local farmers. Thus these systems are more sustainable compared with other food production systems such as monoculture systems. In the north of Jiaxing City, Zhejiang Province, a wide area of low-lying wetlands exists because of land subsidence. The permanently flooded field is not suitable for grain and oilseed rape production and thus agricultural economy development in the area is seriously restricted. As an innovation of IAAS, the trapa-fish (e.g. trapa-loach, trapa-Chinese snakehead fish and trapa-Chinese soft-shelled turtle), lotus-fish (e.g. lotus-loach, lotus-Chinese soft-shelled turtle and lotus-Chinese snakehead fish) and water bamboo-fish (e.g. water bamboo-loach) integrated patterns were being gradually developed in recent years. As an important ecological group in freshwater ecosystems, macrozoobenthos are important in material cycling and energy flow, and are widely used in environmental monitoring. In order to determine the response of macrozoobenthos diversity to lotus-fish farming, field experiments were conducted in Zhejiang Northbay Wetland Eco-agricultural Science and Technology Ltd. Co. Three typical integrated lotus-fish farming systems (including integrated lotus-soft-shelled turtle system, integrated lotus-Oujiang color common carp system and integrated lotus-loach system) along with one monoculture system (soft-shelled turtle monoculture system) were selected in the study. Ecological surveys of each system were carried out at three periods — before lotus-fish co-culture period (late March 2013), after lotus-fish co-culture and the lotus in vigorous growth period (mid-August 2013) and after fish harvesting period (early January 2014). The species composition, standing crops and diversity of samples were analyzed. Altogether, 13 macrozoobenthos taxa belonging to 6 families and 12 genera were identified from all the qualitative and quantitative samples. Results showed that there was no significant difference in the macrozoobenthos species after the adoption of integrated lotus-fish farming system. However, macrozoobenthos biodiversity decreased because of sediment disturbance caused by aquatic animals after fish stocking. The density and biomass of aquatic insects and macrozoobenthos in the integrated lotus-fish farming systems all increased after fish stocking. The average density and biomass of aquatic insects, total density and biomass of macrozoobenthos increased by 12 times and 336 times, 11 times and 273 times, respectively. However, in the soft-shelled turtle monoculture system, macrozoobenthos biomass decreased after soft-shelled turtle stocking. Meanwhile, the integrated lotus-soft-shelled turtle system had higher density and biomass of aquatic insects and macrozoobenthos compared with soft-shelled turtle monoculture system. Conversely, the density and biomass of oligochaetes in integrated lotus-soft- shelled turtle system were lower than those in monoculture system. Results of bioassessment using Hilsenhoff biotic index indicated that water quality under lotus-Oujiang color common carp system was better than that under lotus-loach system and lotus-soft-shelled turtle system.
Integrated Agri-Aquaculture Systems (IAAS) such as rice-fish farming have been practiced for centuries in China. In these systems, on-farm wastes and by-products are recycled in relatively closed nutrient cycles. IAAS also utilizes resource efficiently and provides additional food and income to local farmers. Thus these systems are more sustainable compared with other food production systems such as monoculture systems. In the north of Jiaxing City, Zhejiang Province, a wide area of low-lying wetlands exists because of land subsidence. The permanently flooded field is not suitable for grain and oilseed rape production and thus agricultural economy development in the area is seriously restricted. As an innovation of IAAS, the trapa-fish (e.g. trapa-loach, trapa-Chinese snakehead fish and trapa-Chinese soft-shelled turtle), lotus-fish (e.g. lotus-loach, lotus-Chinese soft-shelled turtle and lotus-Chinese snakehead fish) and water bamboo-fish (e.g. water bamboo-loach) integrated patterns were being gradually developed in recent years. As an important ecological group in freshwater ecosystems, macrozoobenthos are important in material cycling and energy flow, and are widely used in environmental monitoring. In order to determine the response of macrozoobenthos diversity to lotus-fish farming, field experiments were conducted in Zhejiang Northbay Wetland Eco-agricultural Science and Technology Ltd. Co. Three typical integrated lotus-fish farming systems (including integrated lotus-soft-shelled turtle system, integrated lotus-Oujiang color common carp system and integrated lotus-loach system) along with one monoculture system (soft-shelled turtle monoculture system) were selected in the study. Ecological surveys of each system were carried out at three periods — before lotus-fish co-culture period (late March 2013), after lotus-fish co-culture and the lotus in vigorous growth period (mid-August 2013) and after fish harvesting period (early January 2014). The species composition, standing crops and diversity of samples were analyzed. Altogether, 13 macrozoobenthos taxa belonging to 6 families and 12 genera were identified from all the qualitative and quantitative samples. Results showed that there was no significant difference in the macrozoobenthos species after the adoption of integrated lotus-fish farming system. However, macrozoobenthos biodiversity decreased because of sediment disturbance caused by aquatic animals after fish stocking. The density and biomass of aquatic insects and macrozoobenthos in the integrated lotus-fish farming systems all increased after fish stocking. The average density and biomass of aquatic insects, total density and biomass of macrozoobenthos increased by 12 times and 336 times, 11 times and 273 times, respectively. However, in the soft-shelled turtle monoculture system, macrozoobenthos biomass decreased after soft-shelled turtle stocking. Meanwhile, the integrated lotus-soft-shelled turtle system had higher density and biomass of aquatic insects and macrozoobenthos compared with soft-shelled turtle monoculture system. Conversely, the density and biomass of oligochaetes in integrated lotus-soft- shelled turtle system were lower than those in monoculture system. Results of bioassessment using Hilsenhoff biotic index indicated that water quality under lotus-Oujiang color common carp system was better than that under lotus-loach system and lotus-soft-shelled turtle system.
2016, 24(12): 1607-1613.
doi: 10.13930/j.cnki.cjea.160180
Abstract:
The traditional cotton transplanting technique was adopted as an intercropped planting system to improve comprehensive harvest gains in limited acreage fields. However, this method was not suitable for current cotton production because of self-evident production barriers such as intensive labor requirement and overuse of nitrogen fertilizers. The new cotton planting system (field-seeding after barley harvest) without transplanting is more economical in terms of labor input, and therefore more convenient for mechanized cotton production. It is the now prospective direction of cotton production in Yangtze River Valley. To optimize the cultivation strategy of this new cotton cultivation system, the adoption of short-season cotton varieties and simplification of nitrogen application are the key techniques under consideration for the effect of the shortened growth duration of cotton after barley harvest. The objective of the study was to explore the effect of different nitrogen management schemes on yield, biomass and nitrogen use efficiency of short-season cotton variety (cv. CCRI 50) sowed after barley harvest, and to recommend the appropriate nitrogen management scheme under the cultivation system. A field experiment was conducted in 2013 and 2014 at the experimental station of Jiangsu Academy of Agricultural Sciences in Nanjing, Jiangsu Province, China. A split-plot design with three replicates was adopted where the main plot factor was nitrogen application rate and the sub-plot factor was application frequency. There were 5 levels of nitrogen application rate [0 kg(N)·hm-2, 75 kg(N)·hm-2, 150 kg(N)·hm-2, 225 kg(N)·hm-2 and 300 kg(N)·hm-2] and 2 levels of application frequency (1 or 2 times). Biomass and yields, nitrogen use efficiency of cotton were investigated. The results showed that cotton lint yield significantly increased following an increase in nitrogen rate from 0 to 150 kg(N)·hm-2. The cotton lint yield in 2 times fertilizer application treatment was higher than that of one time fertilizer application. The interactive effect of nitrogen rate and application frequency showed that the cotton lint yield was highest under 150 kg (N)·hm-2 nitrogen rate and 2 times application of fertilizer condition. Biomass and nitrogen accumulation also increased with increasing nitrogen rate and application frequency, while reproductive organ distribution ratio decreased. When nitrogen rate exceeded 75 kg(N)·hm-2, apparent nitrogen recovery efficiency (ANRE), agronomic nitrogen efficiency (ANE) and nitrogen production efficiency (NPE) decreased with increasing nitrogen application rate. ANRE and ANE in the 2 times application treatment were higher than those in the one time nitrogen application treatment, but NPE showed the opposite trend. The interactive effects of nitrogen rate and application frequency showed that under 75–150 kg(N)·hm-2 nitrogen application condition, ANRE and ANE with 2 times nitrogen application, while NPE with one time application were higher than others treatments. Correlation analysis showed that lint yields and biomass significantly correlated with nitrogen accumulation, but did not correlate with nitrogen distribution coefficient. Nitrogen utilization rate did not correlate with cotton lint yield. As a result, the optimum nitrogen management was 150 kg(N)·hm-2 with 2 times application for cotton under field-seeding after barley harvest.
The traditional cotton transplanting technique was adopted as an intercropped planting system to improve comprehensive harvest gains in limited acreage fields. However, this method was not suitable for current cotton production because of self-evident production barriers such as intensive labor requirement and overuse of nitrogen fertilizers. The new cotton planting system (field-seeding after barley harvest) without transplanting is more economical in terms of labor input, and therefore more convenient for mechanized cotton production. It is the now prospective direction of cotton production in Yangtze River Valley. To optimize the cultivation strategy of this new cotton cultivation system, the adoption of short-season cotton varieties and simplification of nitrogen application are the key techniques under consideration for the effect of the shortened growth duration of cotton after barley harvest. The objective of the study was to explore the effect of different nitrogen management schemes on yield, biomass and nitrogen use efficiency of short-season cotton variety (cv. CCRI 50) sowed after barley harvest, and to recommend the appropriate nitrogen management scheme under the cultivation system. A field experiment was conducted in 2013 and 2014 at the experimental station of Jiangsu Academy of Agricultural Sciences in Nanjing, Jiangsu Province, China. A split-plot design with three replicates was adopted where the main plot factor was nitrogen application rate and the sub-plot factor was application frequency. There were 5 levels of nitrogen application rate [0 kg(N)·hm-2, 75 kg(N)·hm-2, 150 kg(N)·hm-2, 225 kg(N)·hm-2 and 300 kg(N)·hm-2] and 2 levels of application frequency (1 or 2 times). Biomass and yields, nitrogen use efficiency of cotton were investigated. The results showed that cotton lint yield significantly increased following an increase in nitrogen rate from 0 to 150 kg(N)·hm-2. The cotton lint yield in 2 times fertilizer application treatment was higher than that of one time fertilizer application. The interactive effect of nitrogen rate and application frequency showed that the cotton lint yield was highest under 150 kg (N)·hm-2 nitrogen rate and 2 times application of fertilizer condition. Biomass and nitrogen accumulation also increased with increasing nitrogen rate and application frequency, while reproductive organ distribution ratio decreased. When nitrogen rate exceeded 75 kg(N)·hm-2, apparent nitrogen recovery efficiency (ANRE), agronomic nitrogen efficiency (ANE) and nitrogen production efficiency (NPE) decreased with increasing nitrogen application rate. ANRE and ANE in the 2 times application treatment were higher than those in the one time nitrogen application treatment, but NPE showed the opposite trend. The interactive effects of nitrogen rate and application frequency showed that under 75–150 kg(N)·hm-2 nitrogen application condition, ANRE and ANE with 2 times nitrogen application, while NPE with one time application were higher than others treatments. Correlation analysis showed that lint yields and biomass significantly correlated with nitrogen accumulation, but did not correlate with nitrogen distribution coefficient. Nitrogen utilization rate did not correlate with cotton lint yield. As a result, the optimum nitrogen management was 150 kg(N)·hm-2 with 2 times application for cotton under field-seeding after barley harvest.
2016, 24(12): 1614-1622.
doi: 10.13930/j.cnki.cjea.160489
Abstract:
Currently, the fertilization of maize is not pertinent to actual local situations in northern Shanxi. To solve this problem, a maize specialized fertilizer formula for mild-saline-alkaline soils in northern Shanxi was studied to explore the proper ratio of slow-release nitrogen (SRN) and rapid-release nitrogen (RRN) in maize production in this region and the effectiveness of the formula validated for spring maize. The treatments were 100% RRN and 25%, 33%, 50%, 67%, 75% and 100% SRN, and no nitrogen application was the control. The grain production and dry matter weight at different growth stages, nitrogen uptake, transport and utilization of maize plant, as well as post-harvest nitrate nitrogen accumulation in soil were analyzed. The results showed that with increasing SRN ratio in the maize specialized fertilizer, physiological parameters of maize increased and then decreased at different growth stages. The peaked values of different indicators all occurred under the treatment with 33% SRN. The addition of 33% SRN effectively increased grain production, dry matter weight, nitrogen uptake and nitrogen use efficiency of maize, and with the highest yield of maize of 14 897.46 kg?hm-2. The yield of maize increased by 42.23% compared with 100% RRN treatment. Meanwhile compared with 100% RRN, yield components such as ear length, ear grain number, diameter, 100-seed weight in 33% SRN treatment were higher by 55.34%, 39.30%, 53.57% and 52.57%, respectively. Moreover, in the same treatment, the length of bald tip was shorten by 0.38 cm, while nitrogen use efficiency, nitrogen partial productivity and agronomic efficiency of nitrogen fertilizer were 39.79%, 66.20 kg.kg-1 and 47.03 kg.kg-1, respectively; all of which were the highest in the treatments. The transport rate of nitrogen in different organs of maize was higher in 33% SRN treatment compared with 100% RRN treatment. Specifically, the rates of nitrogen transport in leaf and stem were respectively 76.08% and 49.39%, and the rate of nitrogen transfer and nitrogen harvest index were 67.76% and 77.40%, respectively; all of which were significantly higher than those in 100% RRN treatment. The 33% SRN treatment effectively improved nitrate nitrogen accumulation in the soil, which was different at different soil depths with the least in deep soil layers. It was therefore concluded that for spring maize cultivated in mild-saline-alkali soils in northern Shanxi, the addition of 33% of SRN to the existing maize specialized fertilizer increased maize production and fertilizer use efficiency, and protected the environment. This method was promising in enhancing the conditions (yield and environment) of maize production of the region.
Currently, the fertilization of maize is not pertinent to actual local situations in northern Shanxi. To solve this problem, a maize specialized fertilizer formula for mild-saline-alkaline soils in northern Shanxi was studied to explore the proper ratio of slow-release nitrogen (SRN) and rapid-release nitrogen (RRN) in maize production in this region and the effectiveness of the formula validated for spring maize. The treatments were 100% RRN and 25%, 33%, 50%, 67%, 75% and 100% SRN, and no nitrogen application was the control. The grain production and dry matter weight at different growth stages, nitrogen uptake, transport and utilization of maize plant, as well as post-harvest nitrate nitrogen accumulation in soil were analyzed. The results showed that with increasing SRN ratio in the maize specialized fertilizer, physiological parameters of maize increased and then decreased at different growth stages. The peaked values of different indicators all occurred under the treatment with 33% SRN. The addition of 33% SRN effectively increased grain production, dry matter weight, nitrogen uptake and nitrogen use efficiency of maize, and with the highest yield of maize of 14 897.46 kg?hm-2. The yield of maize increased by 42.23% compared with 100% RRN treatment. Meanwhile compared with 100% RRN, yield components such as ear length, ear grain number, diameter, 100-seed weight in 33% SRN treatment were higher by 55.34%, 39.30%, 53.57% and 52.57%, respectively. Moreover, in the same treatment, the length of bald tip was shorten by 0.38 cm, while nitrogen use efficiency, nitrogen partial productivity and agronomic efficiency of nitrogen fertilizer were 39.79%, 66.20 kg.kg-1 and 47.03 kg.kg-1, respectively; all of which were the highest in the treatments. The transport rate of nitrogen in different organs of maize was higher in 33% SRN treatment compared with 100% RRN treatment. Specifically, the rates of nitrogen transport in leaf and stem were respectively 76.08% and 49.39%, and the rate of nitrogen transfer and nitrogen harvest index were 67.76% and 77.40%, respectively; all of which were significantly higher than those in 100% RRN treatment. The 33% SRN treatment effectively improved nitrate nitrogen accumulation in the soil, which was different at different soil depths with the least in deep soil layers. It was therefore concluded that for spring maize cultivated in mild-saline-alkali soils in northern Shanxi, the addition of 33% of SRN to the existing maize specialized fertilizer increased maize production and fertilizer use efficiency, and protected the environment. This method was promising in enhancing the conditions (yield and environment) of maize production of the region.
2016, 24(12): 1623-1632.
doi: 10.13930/j.cnki.cjea.160449
Abstract:
Alfalfa (Medicago sativa) has high nutritional quality and biomass production and is widely used as pasture in animal production and soil erosion control. There are many factors influencing the production of alfalfa, including fertilizer and water use. The applications of both nitrogen and irrigation have been the critical factors for improving water use efficiency without considerable yield reduction in alfalfa. Thus the determination of a reasonable application of nitrogen and irrigation is important for the optimization of biomass distribution characteristics and improvement of water use efficiency in alfalfa fields in Hexi Corridor. To that end, a field study was conducted in 2014 in Jiuquan City (in the Hexi Corridor of Gansu Province, China) to research the effects of different irrigation amounts (W1: 60% of the conventional irrigation amount; W2: 80% of the conventional irrigation amount; W3: the conventional irrigation amount, 1 920 m3·hm-2) and nitrogen application rates [N1: 0 kg(N)·hm-2; N2: 40 kg(N)·hm-2; N3: 80 kg(N)·hm-2; N4: 120 kg(N)·hm-2] on biomass distribution characteristics and water use efficiency of 2-year alfalfa plantations. The study investigated the effects of nitrogen application, irrigation and the related interaction on alfalfa plant height, branch number per plant, leaf-stem ratio, root volume, root biomass, aboveground- belowground biomass ratio and water use efficiency. The results suggested that W2 and W3 treatments significantly increased plant height, branch number per plant and aboveground biomass. It also increased root biomass, root volume in 2040 cm, 4060 cm and 060 cm soil layer and water use efficiency. Moreover, plant height, branch number per plant and aboveground biomass were not obviously different between W2 and W3 treatments. This suggested that 80% of the conventional irrigation scheme not only maintained normal biomass production in alfalfa plants, but also improved water use efficiency. Branch number per plant, leaf-stem ratio, root volume, root biomass, aboveground-belowground biomass ratio and water use efficiency initially increased and then decreased with increasing nitrogen application. These parameters peaked under the treatment of 80 kg(N)·hm-2 nitrogen, which suggested that nitrogen application significantly influenced root development and water use efficiency of alfalfa plants. Besides this, W2N2 or W2N3 treatments had the potential to optimize plant height, branch number per plant, root volume and belowground biomass in the 020 cm, 2040 cm and 060 cm soil layers. The ratio of aboveground to belowground biomass and water use efficiency was also optimized under W2N2 or W2N3 treatments. It was concluded that 80% of the conventional irrigation amount and 80 kg(N)·hm-2 of nitrogen application were the optimal treatment for alfalfa pasture in Hexi Corridor.
Alfalfa (Medicago sativa) has high nutritional quality and biomass production and is widely used as pasture in animal production and soil erosion control. There are many factors influencing the production of alfalfa, including fertilizer and water use. The applications of both nitrogen and irrigation have been the critical factors for improving water use efficiency without considerable yield reduction in alfalfa. Thus the determination of a reasonable application of nitrogen and irrigation is important for the optimization of biomass distribution characteristics and improvement of water use efficiency in alfalfa fields in Hexi Corridor. To that end, a field study was conducted in 2014 in Jiuquan City (in the Hexi Corridor of Gansu Province, China) to research the effects of different irrigation amounts (W1: 60% of the conventional irrigation amount; W2: 80% of the conventional irrigation amount; W3: the conventional irrigation amount, 1 920 m3·hm-2) and nitrogen application rates [N1: 0 kg(N)·hm-2; N2: 40 kg(N)·hm-2; N3: 80 kg(N)·hm-2; N4: 120 kg(N)·hm-2] on biomass distribution characteristics and water use efficiency of 2-year alfalfa plantations. The study investigated the effects of nitrogen application, irrigation and the related interaction on alfalfa plant height, branch number per plant, leaf-stem ratio, root volume, root biomass, aboveground- belowground biomass ratio and water use efficiency. The results suggested that W2 and W3 treatments significantly increased plant height, branch number per plant and aboveground biomass. It also increased root biomass, root volume in 2040 cm, 4060 cm and 060 cm soil layer and water use efficiency. Moreover, plant height, branch number per plant and aboveground biomass were not obviously different between W2 and W3 treatments. This suggested that 80% of the conventional irrigation scheme not only maintained normal biomass production in alfalfa plants, but also improved water use efficiency. Branch number per plant, leaf-stem ratio, root volume, root biomass, aboveground-belowground biomass ratio and water use efficiency initially increased and then decreased with increasing nitrogen application. These parameters peaked under the treatment of 80 kg(N)·hm-2 nitrogen, which suggested that nitrogen application significantly influenced root development and water use efficiency of alfalfa plants. Besides this, W2N2 or W2N3 treatments had the potential to optimize plant height, branch number per plant, root volume and belowground biomass in the 020 cm, 2040 cm and 060 cm soil layers. The ratio of aboveground to belowground biomass and water use efficiency was also optimized under W2N2 or W2N3 treatments. It was concluded that 80% of the conventional irrigation amount and 80 kg(N)·hm-2 of nitrogen application were the optimal treatment for alfalfa pasture in Hexi Corridor.
2016, 24(12): 1633-1642.
doi: 10.13930/j.cnki.cjea.160357
Abstract:
The quality of straw affects N release after straw retention. As straw with high C/N ratio could result in N immobilization, additional N is needed to compensate N demand of crop. More and more N fertilizer is applied to soil for high crop yields in China. Therefore, how to scientifically apply N fertilizer is a key problem after straw retention. Based on C/N ratio, we carried out a field experiment to study the effects of different C/N ratios on soil mineral N content, microbial parameters and crop yields during the period of 20122013 in a winter wheat-summer maize double cropping system. The field experiment consisted of six treatments: 1) straw removal without fertilizer; 2) straw retention without N fertilizer; 3) straw retention with conventional N fertilizer (C/N ratio 10︰1); 4)straw retention with mineral N fertilizer (adjusted C/N ratio of 16︰1); 5) straw retention with mineral N fertilizer (adjusted C/N ratio of 25︰1); 6) straw retention with an adjusted C/N ratio of 25︰1 using organic N fertilizer (cattle manure). The results showed that: 1) there was no difference between the addition of mineral N fertilizer and organic N fertilizer on soil mineral N content under the same C/N ratio (25︰1) input. In the case of straw retention amended with mineral N fertilizer, C/N ratio of straw retention had significant influence on soil mineral N content, and C/N ratio was negatively related to soil mineral N content. 2) Straw retention amendment with N fertilizer increased soil microbial biomass N content, while no difference in soil microbial biomass N content among different N fertilizer inputs treatments. Straw retention amended with N fertilizer with sitting in integrated judgment, the urease activity had no remarkably different. Straw retention amended with N fertilizer increased FDA hydrolyase activity, and there was an increasing tendency with the decreasing of C/N ratio. 3) Straw retention amended with miner N fertilizer significantly increased crop above-ground biomass. Compared to straw retention and with an adjusted C/N ratio of 25︰1, straw retention with an adjusted C/N ratio of 10︰1 and 16︰1 increased above-ground biomass in both seedling and maturing stage. Compared to straw retention, straw retention amendment with organic N fertilizer had no influence on crop above-ground biomass. Straw retention amendment with miner N fertilizer increased crop yield, especially under the C/N ratio 16︰1 input; however, there was a decreased tendency at straw retention amendment with organic N fertilizer under the C/N ratio 25︰1. We concluded that applying mineral N fertilizer and adjusting C/N ration to 16︰1 may be more suitable N fertilizer practices after straw retention.
The quality of straw affects N release after straw retention. As straw with high C/N ratio could result in N immobilization, additional N is needed to compensate N demand of crop. More and more N fertilizer is applied to soil for high crop yields in China. Therefore, how to scientifically apply N fertilizer is a key problem after straw retention. Based on C/N ratio, we carried out a field experiment to study the effects of different C/N ratios on soil mineral N content, microbial parameters and crop yields during the period of 20122013 in a winter wheat-summer maize double cropping system. The field experiment consisted of six treatments: 1) straw removal without fertilizer; 2) straw retention without N fertilizer; 3) straw retention with conventional N fertilizer (C/N ratio 10︰1); 4)straw retention with mineral N fertilizer (adjusted C/N ratio of 16︰1); 5) straw retention with mineral N fertilizer (adjusted C/N ratio of 25︰1); 6) straw retention with an adjusted C/N ratio of 25︰1 using organic N fertilizer (cattle manure). The results showed that: 1) there was no difference between the addition of mineral N fertilizer and organic N fertilizer on soil mineral N content under the same C/N ratio (25︰1) input. In the case of straw retention amended with mineral N fertilizer, C/N ratio of straw retention had significant influence on soil mineral N content, and C/N ratio was negatively related to soil mineral N content. 2) Straw retention amendment with N fertilizer increased soil microbial biomass N content, while no difference in soil microbial biomass N content among different N fertilizer inputs treatments. Straw retention amended with N fertilizer with sitting in integrated judgment, the urease activity had no remarkably different. Straw retention amended with N fertilizer increased FDA hydrolyase activity, and there was an increasing tendency with the decreasing of C/N ratio. 3) Straw retention amended with miner N fertilizer significantly increased crop above-ground biomass. Compared to straw retention and with an adjusted C/N ratio of 25︰1, straw retention with an adjusted C/N ratio of 10︰1 and 16︰1 increased above-ground biomass in both seedling and maturing stage. Compared to straw retention, straw retention amendment with organic N fertilizer had no influence on crop above-ground biomass. Straw retention amendment with miner N fertilizer increased crop yield, especially under the C/N ratio 16︰1 input; however, there was a decreased tendency at straw retention amendment with organic N fertilizer under the C/N ratio 25︰1. We concluded that applying mineral N fertilizer and adjusting C/N ration to 16︰1 may be more suitable N fertilizer practices after straw retention.
2016, 24(12): 1643-1654.
doi: 10.13930/j.cnki.cjea.160567
Abstract:
Although plastic film mulching is critical for crop production, its widespread use has produced a great deal of residual plastic film and destroyed soil structure, damaged the physical structure of soil and seriously impeded the movement of soil water and solute as well as crop growth. In order to determine the negative effects of residual plastic film on growth of tomato (Lycopersicon esculeutum Miller) at seedling and blooming and fruit-setting stages, plot experiment was conducted with different amounts of residual plastic film in 2015–2016 in a solar greenhouse of the Key Laboratory of Agricultural Soil and Water Engineering in Arid Areas (108°02′E, 34°17′N). Six treatments, including residual plastic film amounts of 0 kg.hm-2, 80 kg.hm-2, 160 kg.hm-2, 320 kg.hm-2, 640 kg.hm-2 and 1 280 kg.hm-2, were set in triplicate plots. The total area of plot filed was 75.6 m2 (6.0 m × 12.6 m) with three replications for each treatment, with each micro-plot size of 1.0 m 4.2 m. The height and stem diameter of the tomato plants were collected during the period from October 2015 to January 2016 and analyzed and then fitted with nonlinear Logistic models to determine the effects of residual plastic film on the biomass accumulation at seedling stage, blooming and fruit-setting stage of tomato. During the experiment, root morphological characteristics, plant height, stem diameter and biomass accumulation of the tomato plants were measured. The results showed that residual plastic film hindered the growth of tomato root at both seedling and blooming and fruit-setting stages. Root volume, root length density and root dry weight density decreased with increasing residual plastic film amount. In addition, as the amount of plastic film residue increased, plant height and stem diameter decreased significantly (P < 0.05). Besides, the rates of increase in plant height and stem diameter decreased with increasing residual plastic film amount. Logistic model accurately simulated the growth process of tomato in fields with residual plastic film less than 1 280 kg.hm-2 (R-2 > 0.87). As the amount of residual plastic film increased, beginning period and full period of tomato biomass accumulation was ahead of time. This implied that the suitable time of fertilization of tomato should be brought forward. Overall, biomass accumulation decreased for the whole tomato growth period. Contrary to biomass accumulation of leaf, that of root, stem, flower and young fruit decreased with increasing residual plastic film amount. The hindering effects of residual plastic film on tomato growth and dry matter accumulation at seedling stage were higher than at blooming and fruit-setting stage. The early period and middle period of tomato biomass accumulation all occurred in advanced. In summary, strengthening water and fertilizer management at seedling stage and bringing forward the application of fertilizer and irrigation were recommended as the proper measures to weaken the detrimental effects of residual plastic film on tomato.
Although plastic film mulching is critical for crop production, its widespread use has produced a great deal of residual plastic film and destroyed soil structure, damaged the physical structure of soil and seriously impeded the movement of soil water and solute as well as crop growth. In order to determine the negative effects of residual plastic film on growth of tomato (Lycopersicon esculeutum Miller) at seedling and blooming and fruit-setting stages, plot experiment was conducted with different amounts of residual plastic film in 2015–2016 in a solar greenhouse of the Key Laboratory of Agricultural Soil and Water Engineering in Arid Areas (108°02′E, 34°17′N). Six treatments, including residual plastic film amounts of 0 kg.hm-2, 80 kg.hm-2, 160 kg.hm-2, 320 kg.hm-2, 640 kg.hm-2 and 1 280 kg.hm-2, were set in triplicate plots. The total area of plot filed was 75.6 m2 (6.0 m × 12.6 m) with three replications for each treatment, with each micro-plot size of 1.0 m 4.2 m. The height and stem diameter of the tomato plants were collected during the period from October 2015 to January 2016 and analyzed and then fitted with nonlinear Logistic models to determine the effects of residual plastic film on the biomass accumulation at seedling stage, blooming and fruit-setting stage of tomato. During the experiment, root morphological characteristics, plant height, stem diameter and biomass accumulation of the tomato plants were measured. The results showed that residual plastic film hindered the growth of tomato root at both seedling and blooming and fruit-setting stages. Root volume, root length density and root dry weight density decreased with increasing residual plastic film amount. In addition, as the amount of plastic film residue increased, plant height and stem diameter decreased significantly (P < 0.05). Besides, the rates of increase in plant height and stem diameter decreased with increasing residual plastic film amount. Logistic model accurately simulated the growth process of tomato in fields with residual plastic film less than 1 280 kg.hm-2 (R-2 > 0.87). As the amount of residual plastic film increased, beginning period and full period of tomato biomass accumulation was ahead of time. This implied that the suitable time of fertilization of tomato should be brought forward. Overall, biomass accumulation decreased for the whole tomato growth period. Contrary to biomass accumulation of leaf, that of root, stem, flower and young fruit decreased with increasing residual plastic film amount. The hindering effects of residual plastic film on tomato growth and dry matter accumulation at seedling stage were higher than at blooming and fruit-setting stage. The early period and middle period of tomato biomass accumulation all occurred in advanced. In summary, strengthening water and fertilizer management at seedling stage and bringing forward the application of fertilizer and irrigation were recommended as the proper measures to weaken the detrimental effects of residual plastic film on tomato.
2016, 24(12): 1655-1662.
doi: 10.13930/j.cnki.cjea.160436
Abstract:
Application of fungus chaff is an important measure improving soil healthy and plant growth. A filed experiment was conducted to investigate the effects of fungus chaff of vinegar residue incorporation on the population of soil microorganism, soil microbial biomass carbon, soil microbial biomass nitrogen and enzyme activity in three crops (maize, sorghum and waxy maize) soil at different growth stages. The experiment contained six treatments, three crops not treated and treated with 25 000 kg·hm2 of fungus chaff. The results showed that the incorporation of fungus chaff significantly increased bacteria, actinomyces and fungi population in the rhizosphere soil layer. The number of soil bacteria increased by 32%54% for the three crops after fungus chaff application throughout the growth period. At maturity, actinomyces population significantly increased, especially in maize rhizosphere soil layer where there was the largest increment of 101%. The trend in fungi population increased at jointing and heading stages after decreasing at maturity stage. The use of fungus chaff in rhizosphere soil increased the activities of enzymes (urease, catalase and invertase). Soil urease activity under sorghum, corn and waxy corn increased with 239%, 189%, and 184%, respectively. Soil catalase activity was highest at heading stage, with a maximum increment of 40%. Three crops showed different trends in soil invertase activity at each stage. The activity of soil invertase under maize was not significantly different among growth stages, with increment of 38%, 28% and 48% respectively at jointing, heading and mature stages. Soil microbial biomass carbon and nitrogen increased in all the crops after fungus chaff application. The increase in soil microbial carbon content was 58.10–407.67 mg.kg-1 and that in microbial nitrogen content was 11.98–27.55 mg.kg-1 across the growth periods of the three crops. This implied that the application of fungus chaff could be used to boost the population of soil microorganisms and enhance soil microbial biomass carbon and nitrogen, and enzyme activity under the three crop types. This in turn enhanced crop yield and made soil productivity more sustainable. It was therefore recommended to apply fungus chaff of vinegar residues to protect and improve future environmental conditions.
Application of fungus chaff is an important measure improving soil healthy and plant growth. A filed experiment was conducted to investigate the effects of fungus chaff of vinegar residue incorporation on the population of soil microorganism, soil microbial biomass carbon, soil microbial biomass nitrogen and enzyme activity in three crops (maize, sorghum and waxy maize) soil at different growth stages. The experiment contained six treatments, three crops not treated and treated with 25 000 kg·hm2 of fungus chaff. The results showed that the incorporation of fungus chaff significantly increased bacteria, actinomyces and fungi population in the rhizosphere soil layer. The number of soil bacteria increased by 32%54% for the three crops after fungus chaff application throughout the growth period. At maturity, actinomyces population significantly increased, especially in maize rhizosphere soil layer where there was the largest increment of 101%. The trend in fungi population increased at jointing and heading stages after decreasing at maturity stage. The use of fungus chaff in rhizosphere soil increased the activities of enzymes (urease, catalase and invertase). Soil urease activity under sorghum, corn and waxy corn increased with 239%, 189%, and 184%, respectively. Soil catalase activity was highest at heading stage, with a maximum increment of 40%. Three crops showed different trends in soil invertase activity at each stage. The activity of soil invertase under maize was not significantly different among growth stages, with increment of 38%, 28% and 48% respectively at jointing, heading and mature stages. Soil microbial biomass carbon and nitrogen increased in all the crops after fungus chaff application. The increase in soil microbial carbon content was 58.10–407.67 mg.kg-1 and that in microbial nitrogen content was 11.98–27.55 mg.kg-1 across the growth periods of the three crops. This implied that the application of fungus chaff could be used to boost the population of soil microorganisms and enhance soil microbial biomass carbon and nitrogen, and enzyme activity under the three crop types. This in turn enhanced crop yield and made soil productivity more sustainable. It was therefore recommended to apply fungus chaff of vinegar residues to protect and improve future environmental conditions.
2016, 24(12): 1663-1673.
doi: 10.13930/j.cnki.cjea.160640
Abstract:
Tomato (Solanum lycopersicum Mill.) is one of the vegetables widely cultivated in solar greenhouses in North China. As irrigation is the main source of soil moisture in solar greenhouse, it is very important to select appropriate irrigation methods and technical parameters to improve agricultural production, keep greenhouse air humidity, and reduce the incidence of pests and diseases. Moistube irrigation is a new underground irrigation technology with semi-permeable membrane as the core material which provides water to crop root zone soils in a slow and continuous flow. The advantages of this new irrigation technology include energy saving, low operation cost, easy operation, good anti-clogging performance, less deep leakage, etc. However, this technology is still in experimental stage and therefore has not been applied at large scale, and some important parameters needed to be optimized. In this experiment, drip irrigation with mulch was used as control to explore suitable technical parameters of moistube irrigation in solar greenhouse conditions. Three depths (10, 20, 30 cm) and three densities (one, two and three moistubes with two lines of tomatoes in one planting ridge, respectively expresses as 1 tube with 2 lines, 2 tubes with 2 lines, 3 tubes with 2 lines) were set up to study the effect of different depths and densities of moistube on the growth, yield and quality of tomato in solar greenhouse conditions. The experiment was done from October 2015 through April 2016 in a 108 m by 8 m solar greenhouse (108°02′E, 34°17′N) in Yangling Agricultural Hi-tech Industries Demonstration Zone, Shaanxi Province, China. The results showed that moistube irrigation enhanced the growth of tomato compared with the drip irrigation with mulch. Compared with control, moistube irrigation increased fruit diameter, weight, volume, total yield and irrigation water use efficiency by 8.58%, 11.99%, 18.79%, 60.93% and 103.40%, respectively. Our results suggested that water-saving under moistube irrigation conditions was as high as 37.73%. For tomato quality, compared with control, the contents of vitamin C, soluble sugar and sugar-acid ratio also increased under moistube irrigation, with average increasing rates of 27.07%, 4.48% and 21.38%, respectively. In terms of comprehensive quality of tomato, the moistube depth was in the order of 30 cm > 10 cm > 20 cm under the same moistube density, the moistube density was in order of 1 tube with 2 lines > 2 tubes with 2 lines > 3 tubes with 2 lines under the same moistube depth. In general, plant height, stem diameter, fruit shape and total yield of tomato decreased with increasing moistube depth. These parameters also increased with increasing moistube density. However, stem diameter and irrigation water use efficiency decreased with increasing moistube density. Based on total yield, irrigation water use efficiency and quality of tomato and the economic cost of moistube and other factors, 10 cm depth and 1 tube with 2 lines (with total tomato yield of 87.38 t.hm-2, irrigation water use efficiency of 108.91 kg.m-3, and third in comprehensive quality rank) were the most suitable technical parameters for moistube irrigation in solar greenhouse condition.
Tomato (Solanum lycopersicum Mill.) is one of the vegetables widely cultivated in solar greenhouses in North China. As irrigation is the main source of soil moisture in solar greenhouse, it is very important to select appropriate irrigation methods and technical parameters to improve agricultural production, keep greenhouse air humidity, and reduce the incidence of pests and diseases. Moistube irrigation is a new underground irrigation technology with semi-permeable membrane as the core material which provides water to crop root zone soils in a slow and continuous flow. The advantages of this new irrigation technology include energy saving, low operation cost, easy operation, good anti-clogging performance, less deep leakage, etc. However, this technology is still in experimental stage and therefore has not been applied at large scale, and some important parameters needed to be optimized. In this experiment, drip irrigation with mulch was used as control to explore suitable technical parameters of moistube irrigation in solar greenhouse conditions. Three depths (10, 20, 30 cm) and three densities (one, two and three moistubes with two lines of tomatoes in one planting ridge, respectively expresses as 1 tube with 2 lines, 2 tubes with 2 lines, 3 tubes with 2 lines) were set up to study the effect of different depths and densities of moistube on the growth, yield and quality of tomato in solar greenhouse conditions. The experiment was done from October 2015 through April 2016 in a 108 m by 8 m solar greenhouse (108°02′E, 34°17′N) in Yangling Agricultural Hi-tech Industries Demonstration Zone, Shaanxi Province, China. The results showed that moistube irrigation enhanced the growth of tomato compared with the drip irrigation with mulch. Compared with control, moistube irrigation increased fruit diameter, weight, volume, total yield and irrigation water use efficiency by 8.58%, 11.99%, 18.79%, 60.93% and 103.40%, respectively. Our results suggested that water-saving under moistube irrigation conditions was as high as 37.73%. For tomato quality, compared with control, the contents of vitamin C, soluble sugar and sugar-acid ratio also increased under moistube irrigation, with average increasing rates of 27.07%, 4.48% and 21.38%, respectively. In terms of comprehensive quality of tomato, the moistube depth was in the order of 30 cm > 10 cm > 20 cm under the same moistube density, the moistube density was in order of 1 tube with 2 lines > 2 tubes with 2 lines > 3 tubes with 2 lines under the same moistube depth. In general, plant height, stem diameter, fruit shape and total yield of tomato decreased with increasing moistube depth. These parameters also increased with increasing moistube density. However, stem diameter and irrigation water use efficiency decreased with increasing moistube density. Based on total yield, irrigation water use efficiency and quality of tomato and the economic cost of moistube and other factors, 10 cm depth and 1 tube with 2 lines (with total tomato yield of 87.38 t.hm-2, irrigation water use efficiency of 108.91 kg.m-3, and third in comprehensive quality rank) were the most suitable technical parameters for moistube irrigation in solar greenhouse condition.
Ecological regionalization of cotton fiber quality in the Northwest Inland Region using GGE analysis
2016, 24(12): 1674-1682.
doi: 10.13930/j.cnki.cjea.160634
Abstract:
This paper analyzed the distribution characteristics of cotton fiber quality using environmental materials from 7 sites of early-maturing and 10 sites of medium-early maturing cotton of regional trials in the Northwest Inland in China during 2005–2014. Using the GGE model to draw biplots, cotton fiber quality performance and environmental interaction patterns and the correlation between spinning consistency index and fiber trait were explored, and the GGE biplot method was also used to zone potential ecological sub-regions. The aim of the study was to provide the basis for regional cultivation of cotton varieties, and the ideal experimental environment in the Northwest Inland for improving cotton fiber and yarn quality in the country. The research results showed that cotton fiber quality traits were correlated with each other. The spinning consistency index significantly positively correlated with fiber length, strength and index uniformity. The cultivation regions were divided into three ecological sub-regions based on cotton fiber quality in the early maturing cotton cultivation area. These sub-regions included the high quality cotton fiber ecological sub-region (i.e. Jinghe), the common high quality fiber ecological sub-region (Sixth Divisions of Agricultural Production and Construction Corps in Xinjiang, i.e., ACD6 and Usu City) and the common fiber ecological sub-region (Dunhuang, 125 Tuan of ACD7, 121 Tuan of ACD8 and Shihezi). The medium-early maturing cotton cultivation area in the Northwest Inland was also divided into three sub-regions. They were the high quality cotton fiber ecological sub-region (Yarkand, Luntai, Bazhou, Kuqa, Shufu, 13 Tuan and 10 Tuan Tahe of Alaer ACD1), the common high quality fiber ecological sub-region (Maigaiti and Kashi of ACD3) and the common fiber ecological sub-region (Aksu). It was therefore important to cultivate the early maturing cotton with good comprehensive quality traits, and to improve fiber length and strength in the early maturing cotton cultivation area of the Northwest Inland. In the medium-early maturing cotton region, cotton varieties with specific length and strength suitable for mechanical weaving requirements should be cultivated, and the harvest time also should be reasonable to increase fiber maturity and reduced micro-naire. Regionalization of optimized cultivation area for cotton spinning requirements could provide multi-level raw cotton materials in the Northwest Inland.
This paper analyzed the distribution characteristics of cotton fiber quality using environmental materials from 7 sites of early-maturing and 10 sites of medium-early maturing cotton of regional trials in the Northwest Inland in China during 2005–2014. Using the GGE model to draw biplots, cotton fiber quality performance and environmental interaction patterns and the correlation between spinning consistency index and fiber trait were explored, and the GGE biplot method was also used to zone potential ecological sub-regions. The aim of the study was to provide the basis for regional cultivation of cotton varieties, and the ideal experimental environment in the Northwest Inland for improving cotton fiber and yarn quality in the country. The research results showed that cotton fiber quality traits were correlated with each other. The spinning consistency index significantly positively correlated with fiber length, strength and index uniformity. The cultivation regions were divided into three ecological sub-regions based on cotton fiber quality in the early maturing cotton cultivation area. These sub-regions included the high quality cotton fiber ecological sub-region (i.e. Jinghe), the common high quality fiber ecological sub-region (Sixth Divisions of Agricultural Production and Construction Corps in Xinjiang, i.e., ACD6 and Usu City) and the common fiber ecological sub-region (Dunhuang, 125 Tuan of ACD7, 121 Tuan of ACD8 and Shihezi). The medium-early maturing cotton cultivation area in the Northwest Inland was also divided into three sub-regions. They were the high quality cotton fiber ecological sub-region (Yarkand, Luntai, Bazhou, Kuqa, Shufu, 13 Tuan and 10 Tuan Tahe of Alaer ACD1), the common high quality fiber ecological sub-region (Maigaiti and Kashi of ACD3) and the common fiber ecological sub-region (Aksu). It was therefore important to cultivate the early maturing cotton with good comprehensive quality traits, and to improve fiber length and strength in the early maturing cotton cultivation area of the Northwest Inland. In the medium-early maturing cotton region, cotton varieties with specific length and strength suitable for mechanical weaving requirements should be cultivated, and the harvest time also should be reasonable to increase fiber maturity and reduced micro-naire. Regionalization of optimized cultivation area for cotton spinning requirements could provide multi-level raw cotton materials in the Northwest Inland.
2016, 24(12): 1683-1692.
doi: 10.13930/j.cnki.cjea.160573
Abstract:
Winter wheat is one of the most important staple crops in the North China Plain. With intensifying challenges of climate change and water shortage, the need for sustainable and high efficiency winter wheat production is becoming more pressing. Clear understanding of the control factors of wheat production can provide the necessary basis for the regulation of a smart winter wheat production policy. Hebei Province is one of the major winter wheat production regions in North China. Annual records (2004–2013) of wheat yield and agricultural information for each county in the province were used to analyze the spatial distribution of yield variation of winter wheat along with the control factors. The major winter wheat production area (which consists of 101 counties with winter wheat area greater than 20% of total cropping area of the county) in Hebei Province was selected and divided into 4 zones (Ⅰ–Ⅳ) using hierarchical clustering analysis based on maximum, minimum and average yields. A principal component analysis was conducted using the average and variation indexes (minimum, maximum, bottom and top boundaries of the 95% confidence interval) of the agricultural variables for winter wheat production, including irrigated area, fertilizer and pesticide amount as well as annual rainfall in each county. Five derived principal factors represented fertilizer (F1), pesticide (F2), irrigation (F3), annual rainfall (F4) and minimum rainfall (F5). Based on the factor score values of the factor models, a stepwise regression analysis model was developed to assess the spatial variation of winter wheat yield as an independent factor (Y). The results showed that from zone Ⅰ to zone Ⅳ, averaged winter wheat yield decreased, whereby temporal yield variation increased significantly (P < 0.05). Zone Ⅰ mostly covered central Hebei Plain including Gaocheng and Luancheng Counties to the east of Shijiazhuang City. Zones Ⅱ, Ⅲ and Ⅳ diverged from the central to the peripheral of Hebei Plain in that sequence, especially zone Ⅳ which only covered the southwest and northeast corner with the lowest yield and the highest variation. Model analysis showed that Y was significantly correlated with F1, F3, F4 and F5 (R2 = 0.685, P < 0.01) and these factors explained 68.5% of Y, where irrigation (F3) was the most important factor explaining 37.4% and fertilizer (F1) explaining 21.7%. Annual rainfall F4 and F5 together explained only 9.4% of the whole model result, indicating a minor effect of annual rainfall on the spatial distribution of winter wheat production in Hebei Province. Pesticide (F2) was not factored into the Y regression model, showing that the use of pesticide had no significant effect on winter wheat production. It underlined the point that plant diseases and pests happened at random and with no regional tendency in winter wheat production. Regression analysis on winter wheat yield and the ratio of winter wheat area to total cropped area (F6) showed that F6 coincidently varied with winter wheat yield among different counties (R2 = 0.409, P < 0.05). Only a few counties to the far east of the low plain close to the coast belonging to zone Ⅳ with the lowest winter wheat yield but abnormally high F6. The results showed that winter wheat production was basically more proper under the existing management mode. However, under severe water shortage conditions, the abnormally high F6 value with low yield spots needed careful examination to insure a healthy and sustainable high-efficiency cropping system. Otherwise winter wheat production should be reduced in low yield areas because irrigation was the most important controlling factor of production. Nevertheless, in this study, only 68.5% of the production variables were explored. This implied that there were other factors not only taken into account in the analysis but also affected winter wheat production.
Winter wheat is one of the most important staple crops in the North China Plain. With intensifying challenges of climate change and water shortage, the need for sustainable and high efficiency winter wheat production is becoming more pressing. Clear understanding of the control factors of wheat production can provide the necessary basis for the regulation of a smart winter wheat production policy. Hebei Province is one of the major winter wheat production regions in North China. Annual records (2004–2013) of wheat yield and agricultural information for each county in the province were used to analyze the spatial distribution of yield variation of winter wheat along with the control factors. The major winter wheat production area (which consists of 101 counties with winter wheat area greater than 20% of total cropping area of the county) in Hebei Province was selected and divided into 4 zones (Ⅰ–Ⅳ) using hierarchical clustering analysis based on maximum, minimum and average yields. A principal component analysis was conducted using the average and variation indexes (minimum, maximum, bottom and top boundaries of the 95% confidence interval) of the agricultural variables for winter wheat production, including irrigated area, fertilizer and pesticide amount as well as annual rainfall in each county. Five derived principal factors represented fertilizer (F1), pesticide (F2), irrigation (F3), annual rainfall (F4) and minimum rainfall (F5). Based on the factor score values of the factor models, a stepwise regression analysis model was developed to assess the spatial variation of winter wheat yield as an independent factor (Y). The results showed that from zone Ⅰ to zone Ⅳ, averaged winter wheat yield decreased, whereby temporal yield variation increased significantly (P < 0.05). Zone Ⅰ mostly covered central Hebei Plain including Gaocheng and Luancheng Counties to the east of Shijiazhuang City. Zones Ⅱ, Ⅲ and Ⅳ diverged from the central to the peripheral of Hebei Plain in that sequence, especially zone Ⅳ which only covered the southwest and northeast corner with the lowest yield and the highest variation. Model analysis showed that Y was significantly correlated with F1, F3, F4 and F5 (R2 = 0.685, P < 0.01) and these factors explained 68.5% of Y, where irrigation (F3) was the most important factor explaining 37.4% and fertilizer (F1) explaining 21.7%. Annual rainfall F4 and F5 together explained only 9.4% of the whole model result, indicating a minor effect of annual rainfall on the spatial distribution of winter wheat production in Hebei Province. Pesticide (F2) was not factored into the Y regression model, showing that the use of pesticide had no significant effect on winter wheat production. It underlined the point that plant diseases and pests happened at random and with no regional tendency in winter wheat production. Regression analysis on winter wheat yield and the ratio of winter wheat area to total cropped area (F6) showed that F6 coincidently varied with winter wheat yield among different counties (R2 = 0.409, P < 0.05). Only a few counties to the far east of the low plain close to the coast belonging to zone Ⅳ with the lowest winter wheat yield but abnormally high F6. The results showed that winter wheat production was basically more proper under the existing management mode. However, under severe water shortage conditions, the abnormally high F6 value with low yield spots needed careful examination to insure a healthy and sustainable high-efficiency cropping system. Otherwise winter wheat production should be reduced in low yield areas because irrigation was the most important controlling factor of production. Nevertheless, in this study, only 68.5% of the production variables were explored. This implied that there were other factors not only taken into account in the analysis but also affected winter wheat production.
2016, 24(12): 1693-1702.
doi: 10.13930/j.cnki.cjea.160456
Abstract:
Complex terrain features affect the land use in the karst mountain regions. Vertical changes of land uses impact on their total qualities and utilization efficiencies. Characterizing the vertical distribution of land use change can guide the land use spatial management and optimization. The conventional methods were used to analyze the vertical distribution of the land use change for the entire study area in the large-scale analysis of previous studies, which may ignore the locally spatial information and discrimination. Taking the Guizhou and Guangxi karst mountainous region as the study area, the newly vertical gradient index of land use change, including the elevation gradient index and slope gradient index, were built and used to characterize and analyze the locally vertical distribution of land use change in the typical karst mountain. Results showed a relatively small net area of land use change, but a violently mutual conversion of various land use types in the study area from 1990 to 2010. Considerable arable lands were occupied by the expanded built-up lands, and the forests and grasslands were reclaimed to the arable land. Meanwhile, the forest, grassland and water body increased significantly because of the ecological restoration project. The conversion between the arable land, forest and grassland was the most intense. It showed a significant mismatch of the vertical distribution for the increased and decreased arable land. Decreased arable lands were primarily located in the region with the low altitude (0200 m) and gentle slope (05). In contrast, the increased arable lands were primarily located in the area with the high altitude (6001 400 m) and steep slope (825). It was a reciprocal relationship of vertical distribution between the increased and decreased forests and grassland, both types peaked at the altitude of 8001 400 m and the slope of 825. The increased water body and built-up land were primarily located in area with the low altitude (0800 m) and gentle slope (05). The vertical gradient index of land use change could quantify and visualize the local distribution and relative degree of land use change trend. Based on the vertical gradient index, most vertical distribution of land use change at local scale were found to be consistent to those at global scale, but also parts were different, which were not founded by the traditional methods. Although the newly expanded built-up land from 2000 to 2010 were mostly located in area of the lowest elevation and gentle slope class, they tended to be located in area with the relatively higher altitude and steeper slope compared to the originally vertical distribution at the local scale. Limited land resources leaded to the development of land uses approaching area with the relatively higher altitude and steeper slope in the Guizhou and Guangxi Karst Mountainous Region. The results demonstrated that the vertical gradient index of land use change might further support the results from the global statistical analysis, but also could analyze and explore the vertical distribution of land use change at the local scale, which was easily omitted by the traditional methods.
Complex terrain features affect the land use in the karst mountain regions. Vertical changes of land uses impact on their total qualities and utilization efficiencies. Characterizing the vertical distribution of land use change can guide the land use spatial management and optimization. The conventional methods were used to analyze the vertical distribution of the land use change for the entire study area in the large-scale analysis of previous studies, which may ignore the locally spatial information and discrimination. Taking the Guizhou and Guangxi karst mountainous region as the study area, the newly vertical gradient index of land use change, including the elevation gradient index and slope gradient index, were built and used to characterize and analyze the locally vertical distribution of land use change in the typical karst mountain. Results showed a relatively small net area of land use change, but a violently mutual conversion of various land use types in the study area from 1990 to 2010. Considerable arable lands were occupied by the expanded built-up lands, and the forests and grasslands were reclaimed to the arable land. Meanwhile, the forest, grassland and water body increased significantly because of the ecological restoration project. The conversion between the arable land, forest and grassland was the most intense. It showed a significant mismatch of the vertical distribution for the increased and decreased arable land. Decreased arable lands were primarily located in the region with the low altitude (0200 m) and gentle slope (05). In contrast, the increased arable lands were primarily located in the area with the high altitude (6001 400 m) and steep slope (825). It was a reciprocal relationship of vertical distribution between the increased and decreased forests and grassland, both types peaked at the altitude of 8001 400 m and the slope of 825. The increased water body and built-up land were primarily located in area with the low altitude (0800 m) and gentle slope (05). The vertical gradient index of land use change could quantify and visualize the local distribution and relative degree of land use change trend. Based on the vertical gradient index, most vertical distribution of land use change at local scale were found to be consistent to those at global scale, but also parts were different, which were not founded by the traditional methods. Although the newly expanded built-up land from 2000 to 2010 were mostly located in area of the lowest elevation and gentle slope class, they tended to be located in area with the relatively higher altitude and steeper slope compared to the originally vertical distribution at the local scale. Limited land resources leaded to the development of land uses approaching area with the relatively higher altitude and steeper slope in the Guizhou and Guangxi Karst Mountainous Region. The results demonstrated that the vertical gradient index of land use change might further support the results from the global statistical analysis, but also could analyze and explore the vertical distribution of land use change at the local scale, which was easily omitted by the traditional methods.
2016, 24(12): 1703-1713.
doi: 10.13930/j.cnki.cjea.160206
Abstract:
In pace with sustainable growth of tea drinking habit prevalent in the world today, the scale of tea plantation which is traditional agriculture activity in China, has been rapidly expanding. Accordingly, a mainly market-driven factor is the economic benefit of tea, but the effect of planting tea on the eco-environment has been easily ignored. In this paper, the specialized tea planting region of Anxi County in Fujian Province was used as a case study to grade the specialization of tea planting among towns. A total of 5 levels of tea planting specialization (high, sub-high, middle, low and no tea planting) were graded with the integration of 3 indices (tea planting area, location quotient and coefficient of concentration) in the study. Based on emergy theory and method, emergy investment and output indices were calculated and 8 emergy evaluation indices were used to analyze agricultural ecosystems at different specialized levels of tea planting. The study showed that: (1) the operation of Anxi’s specialized tea planting agricultural ecosystem was given priority to renewable environmental resources. The environmental contribution ratio for different specialized levels of tea planting was 0.96–0.99 while the emergy investment ratio was only 0.01–0.04. (2) A positive correlation existed between the density of emergy yield and specialized levels of tea planting. Agricultural ecosystem productivity improved with increasing specialized level of tea planting. Then the density of emergy output of high specialization tea planting was 4.15E+11 sej·m-2, which was 1.32 times that of specialized level of no tea planting. (3) Specialized tea planting agricultural ecosystem had high production efficiency and economic benefit, with a positive correlation between emergy yield ratio and specialized level of tea planting. The emergy yield ratio of tea planting and high specialization was 1.29, which was 2.86 times that of specialized level of no tea planting. The environmental load ratio of each specialized level was 0.05, indicating that its environmental friendly nature. (4) Specialized tea planting reduced agricultural ecosystem stability and there was a negative correlation between system stability index and specialized level of tea planting. The system stability index of specialized level of no tea planting was 1.12, which was 1.56 times that of high specialization level. The corresponding countermeasures and suggestions based on the results were therefore as follows: (1) there was the need for compound ecological tea garden construction to focus on improving the biodiversity and stability of tea planting agricultural ecosystems with increasing specialization. (2) It was necessary to pay more attention on the management and technical aspects of agricultural production for well-coordinated and sustainable development of tea productivity capacity in the study area.
In pace with sustainable growth of tea drinking habit prevalent in the world today, the scale of tea plantation which is traditional agriculture activity in China, has been rapidly expanding. Accordingly, a mainly market-driven factor is the economic benefit of tea, but the effect of planting tea on the eco-environment has been easily ignored. In this paper, the specialized tea planting region of Anxi County in Fujian Province was used as a case study to grade the specialization of tea planting among towns. A total of 5 levels of tea planting specialization (high, sub-high, middle, low and no tea planting) were graded with the integration of 3 indices (tea planting area, location quotient and coefficient of concentration) in the study. Based on emergy theory and method, emergy investment and output indices were calculated and 8 emergy evaluation indices were used to analyze agricultural ecosystems at different specialized levels of tea planting. The study showed that: (1) the operation of Anxi’s specialized tea planting agricultural ecosystem was given priority to renewable environmental resources. The environmental contribution ratio for different specialized levels of tea planting was 0.96–0.99 while the emergy investment ratio was only 0.01–0.04. (2) A positive correlation existed between the density of emergy yield and specialized levels of tea planting. Agricultural ecosystem productivity improved with increasing specialized level of tea planting. Then the density of emergy output of high specialization tea planting was 4.15E+11 sej·m-2, which was 1.32 times that of specialized level of no tea planting. (3) Specialized tea planting agricultural ecosystem had high production efficiency and economic benefit, with a positive correlation between emergy yield ratio and specialized level of tea planting. The emergy yield ratio of tea planting and high specialization was 1.29, which was 2.86 times that of specialized level of no tea planting. The environmental load ratio of each specialized level was 0.05, indicating that its environmental friendly nature. (4) Specialized tea planting reduced agricultural ecosystem stability and there was a negative correlation between system stability index and specialized level of tea planting. The system stability index of specialized level of no tea planting was 1.12, which was 1.56 times that of high specialization level. The corresponding countermeasures and suggestions based on the results were therefore as follows: (1) there was the need for compound ecological tea garden construction to focus on improving the biodiversity and stability of tea planting agricultural ecosystems with increasing specialization. (2) It was necessary to pay more attention on the management and technical aspects of agricultural production for well-coordinated and sustainable development of tea productivity capacity in the study area.
2016, 24(12): 1714-1721.
doi: 10.13930/j.cnki.cjea.160476
Abstract:
With rapid urbanization and increasing cost of farming, the jasmine planting area in Fuzhou City has been decreasing sharply and thereby severely threating the important agricultural heritage system — Fuzhou Jasmine and Tea Cultural System. Sustainability of jasmine farming lies in whether the growers have the willingness for continually planting the crop. Thus to explore planting willingness and its influencing factors was critical for developing scientific protection measures to ensure continuity of jasmine farming. In this study, data on social characteristics of jasmine planters (including age, sex, educational level, source of information, cognitive level of the functions of jasmine planters) and their economic characteristics (including current income per hectare, income position in friends and expected income per hectare) as well as planting willingness were collected using questionnaire survey and household interview. Then the general descriptive statistical method was used to analyze statistical characteristics of the data. The Binary Logistic Regression was used to analyze the relationship between the socio-economic characteristics and planting willingness of jasmine planters in order to determine the main factors influencing planting willingness. The results showed that: 1) the jasmine farmers showed a trend of aged population, and their education level was generally low. Furthermore, most information they got relied on laggard and simplex information sources. This hindered the sustainable development of jasmine farming in the study area. 2) Jasmine growers had low cognitive level of the jasmine uses, which also hindered diversified development of jasmine industries around multi-function jasmine farming. 3) The growers that planned to continue with the cultivation of jasmine slightly exceeded one half the population of jasmine farmers. The chose to continue with jasmine cultivation was because of the strong affection for jasmine after cultivation of the crop over a long time. However, jasmine farmers who wanted to stop growing the crop cited “tedious work requirement” and “low profits” as the reason for stopping. 4) The amount of information acquired by growers and the expected income per unit area were the two main factors influencing planting willingness of the farmers. In response to the situations, protection measures needed to be taken were as follows: 1) Building a sustainable mechanism, for example, to provide subsidy to jasmine planters, privilege policies for jasmine growers and start-up business funds to graduates to attract young talents to jasmine farming. 2) Promoting cooperation between enterprises and households and between households to improve income stability of jasmine farmers. 3) Developing tourism, leisure agriculture, etc. to diversify income sources based on the multi-functions of jasmine farming. 4) Improving farming efficiency by devising new production equipment that increased the income of jasmine growers. 5) Training jasmine growers in jasmine farming knowhow and technologies to strengthen self-developing ability. 6) Conducting the practice and education of Important Agricultural Heritage Systems in primary and middle schools to cultivate the love for jasmine from youthful age.
With rapid urbanization and increasing cost of farming, the jasmine planting area in Fuzhou City has been decreasing sharply and thereby severely threating the important agricultural heritage system — Fuzhou Jasmine and Tea Cultural System. Sustainability of jasmine farming lies in whether the growers have the willingness for continually planting the crop. Thus to explore planting willingness and its influencing factors was critical for developing scientific protection measures to ensure continuity of jasmine farming. In this study, data on social characteristics of jasmine planters (including age, sex, educational level, source of information, cognitive level of the functions of jasmine planters) and their economic characteristics (including current income per hectare, income position in friends and expected income per hectare) as well as planting willingness were collected using questionnaire survey and household interview. Then the general descriptive statistical method was used to analyze statistical characteristics of the data. The Binary Logistic Regression was used to analyze the relationship between the socio-economic characteristics and planting willingness of jasmine planters in order to determine the main factors influencing planting willingness. The results showed that: 1) the jasmine farmers showed a trend of aged population, and their education level was generally low. Furthermore, most information they got relied on laggard and simplex information sources. This hindered the sustainable development of jasmine farming in the study area. 2) Jasmine growers had low cognitive level of the jasmine uses, which also hindered diversified development of jasmine industries around multi-function jasmine farming. 3) The growers that planned to continue with the cultivation of jasmine slightly exceeded one half the population of jasmine farmers. The chose to continue with jasmine cultivation was because of the strong affection for jasmine after cultivation of the crop over a long time. However, jasmine farmers who wanted to stop growing the crop cited “tedious work requirement” and “low profits” as the reason for stopping. 4) The amount of information acquired by growers and the expected income per unit area were the two main factors influencing planting willingness of the farmers. In response to the situations, protection measures needed to be taken were as follows: 1) Building a sustainable mechanism, for example, to provide subsidy to jasmine planters, privilege policies for jasmine growers and start-up business funds to graduates to attract young talents to jasmine farming. 2) Promoting cooperation between enterprises and households and between households to improve income stability of jasmine farmers. 3) Developing tourism, leisure agriculture, etc. to diversify income sources based on the multi-functions of jasmine farming. 4) Improving farming efficiency by devising new production equipment that increased the income of jasmine growers. 5) Training jasmine growers in jasmine farming knowhow and technologies to strengthen self-developing ability. 6) Conducting the practice and education of Important Agricultural Heritage Systems in primary and middle schools to cultivate the love for jasmine from youthful age.
2016, 24(12): 1722-1731.
doi: 10.13930/j.cnki.cjea.160548
Abstract:
Traditional water resources planning usually focuses on “blue water” in the hydrologic cycle, ignoring “green water” which accounts for over 60% of the hydrologic cycle. The method of water resources planning at watershed scale based on the concept of eco-hydrology involves a comprehensive analysis of a combined system composed of water resources, social economy and ecological environment through water consumption management to attain sustainable regional development. This paper, from the precipitation of watershed, analyzed the conversion of precipitation from “blue water” to “green water” and constructed a watershed-scale water resources planning model based on the concept of eco-hydrology that contained water resources system module, social economy system module and ecological environment system module. The computation of “green water”, which is the core module of the water resources planning model, adopted the Penman-Monteith model based on the Leaf Area Index (LAI) of MODIS remote sensing and optimized parameters based on the spatial differences of vegetation in the watershed. The “green water” computation was achieved through the transformation of water from the traditional evapotranspiration model at a single-point scale to a multiple-point scale of the watershed evapotranspiration model. Also the processes spatial and temporal variations of two key parameters, including soil evapotranspiration coefficient and vegetation stomatal conductance, were established. Finally, the model was used to simulate water resources planning in a watershed, which involving the actual water consumption by vegetation ecology, residential use, industrial production, food production and different trees/grass. By using Ziya River basin as a case study and 2008 as the reference year, the paper calibrated and verified the parameters of the model and the relative error between the monthly simulated and measured evaporation of different vegetation types (7%), which proved that the model had an acceptable simulation accuracy. By matching planting structure, water-saving irrigation regime, industrial structure, residential water use and aquaculture water use with engineering measures of the middle line of the South-to-North Water Transfer Project, the constructed water resources planning model was used to quantify different planning measures. The results showed that under 50%–75% rate of assurance, water use by natural vegetation was 8.82–7.63 billion m3, that by agriculture was 14.21–12.68 billion m3 and those by urban life, industrial production, tertiary industry and rural life were respectively 0.79, 0.26, 0.31 and 0.33 billion m3. Water consumption in Ziya River basin dropped by 1.19 billion m3 under 75% assurance rate and by 1.32 billion m3 under 50% assurance rate after the implementation of the planning measures. Agricultural production (as the largest water consumer) contributed the most to the water consumption cut, which reached 0.76 billion m3 under 75% assurance rate and 0.88 billion m3 under 50% assurance rate after using the planning measures. This was at least 60% of the total water consumption cut, indicating that the adjustment of planting structure and irrigation pattern was critical in cutting down water consumption in Ziya River basin. The results of the study provided necessary technical support for the efficient and sustainable utilization of water resources in watershed.
Traditional water resources planning usually focuses on “blue water” in the hydrologic cycle, ignoring “green water” which accounts for over 60% of the hydrologic cycle. The method of water resources planning at watershed scale based on the concept of eco-hydrology involves a comprehensive analysis of a combined system composed of water resources, social economy and ecological environment through water consumption management to attain sustainable regional development. This paper, from the precipitation of watershed, analyzed the conversion of precipitation from “blue water” to “green water” and constructed a watershed-scale water resources planning model based on the concept of eco-hydrology that contained water resources system module, social economy system module and ecological environment system module. The computation of “green water”, which is the core module of the water resources planning model, adopted the Penman-Monteith model based on the Leaf Area Index (LAI) of MODIS remote sensing and optimized parameters based on the spatial differences of vegetation in the watershed. The “green water” computation was achieved through the transformation of water from the traditional evapotranspiration model at a single-point scale to a multiple-point scale of the watershed evapotranspiration model. Also the processes spatial and temporal variations of two key parameters, including soil evapotranspiration coefficient and vegetation stomatal conductance, were established. Finally, the model was used to simulate water resources planning in a watershed, which involving the actual water consumption by vegetation ecology, residential use, industrial production, food production and different trees/grass. By using Ziya River basin as a case study and 2008 as the reference year, the paper calibrated and verified the parameters of the model and the relative error between the monthly simulated and measured evaporation of different vegetation types (7%), which proved that the model had an acceptable simulation accuracy. By matching planting structure, water-saving irrigation regime, industrial structure, residential water use and aquaculture water use with engineering measures of the middle line of the South-to-North Water Transfer Project, the constructed water resources planning model was used to quantify different planning measures. The results showed that under 50%–75% rate of assurance, water use by natural vegetation was 8.82–7.63 billion m3, that by agriculture was 14.21–12.68 billion m3 and those by urban life, industrial production, tertiary industry and rural life were respectively 0.79, 0.26, 0.31 and 0.33 billion m3. Water consumption in Ziya River basin dropped by 1.19 billion m3 under 75% assurance rate and by 1.32 billion m3 under 50% assurance rate after the implementation of the planning measures. Agricultural production (as the largest water consumer) contributed the most to the water consumption cut, which reached 0.76 billion m3 under 75% assurance rate and 0.88 billion m3 under 50% assurance rate after using the planning measures. This was at least 60% of the total water consumption cut, indicating that the adjustment of planting structure and irrigation pattern was critical in cutting down water consumption in Ziya River basin. The results of the study provided necessary technical support for the efficient and sustainable utilization of water resources in watershed.
Editor-in-chief：LIU Changming
Competent Authorities：Chinese Academy of Sciences
Sponsored by：Institute of Genetics and Developmental Biology, Chinese Academy of Sciences; China Ecological Economics Society
Organizer：Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences
ISSN 2096-6237
CN 13-1432/S
- Chinese core periodicals
- Core Chinese Sci-Tech Periodicals
- China's Top Science and Technology Periodicals
- Covered by Chinese Science Citation Database (CSCD)
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