Effects of subsurface organic ameliorant combined with film mulching on saline soil organic and inorganic carbon in Hetao Irrigation District
-
摘要: 土壤有机碳(SOC)和无机碳(SIC)是参与全球碳循环的重要碳库。亚表层(10~30 cm)培肥结合地膜覆盖措施是干旱区优化盐碱土壤物理结构和调控土壤水盐环境的有效措施, 然而关于其如何调控0~60 cm土体SOC、SIC分布及其与土壤相关理化性状的关系尚不明确。本研究基于内蒙古河套灌区盐碱土壤6年的田间微区试验, 设置常规对照(CK)、亚表层(10~30 cm)有机培肥(OM)、地膜覆盖(PM)、亚表层有机培肥+地膜覆盖(OM+PM) 4个处理, 测定了2019—2020年0~60 cm剖面SOC、SIC、全碳(TC)含量以及土壤理化指标(土壤水分、盐分、pH和全氮), 分析了TC、SOC、SIC变化特征及其影响因素。结果表明: OM和OM+PM处理较CK和PM处理显著增加0~40 cm土层SOC含量31.9%~195.6% (P<0.05), 显著增加40~60 cm SOC含量33.7%~49.4% (P<0.05, 仅2020年), 但显著降低0~40 cm SIC含量9.9%~35.0% (P<0.05)。基于SOC和SIC的变化, OM+PM较CK处理显著增加2019年20~60 cm TC含量10.4%~39.4% (P<0.05), 并显著增加2020年0~20 cm TC含量13.0% (P<0.05)。回归分析结果进一步说明, 覆膜条件下补充亚表层培肥, 使总碳库变化的主导因素由SIC转变为SOC。冗余分析结果表明土壤理化性质是影响土壤碳库的主要因素(解释度为60.7%~91.9%), 其中全氮和pH是0~40 cm土壤碳库的主要影响因子, 而40~60 cm土壤碳库主要受盐分和pH影响。相关性分析结果表明SOC与SIC表现为完全相反的变化规律, 其中SOC与全氮极显著正相关, 与盐分和pH呈极显著负相关(P<0.01); SIC与全氮呈极显著负相关, 与pH呈极显著正相关(P<0.01)。因此, 亚表层培肥结合地膜覆盖可以通过增加SOC来弥补SIC的损失进而实现碳积累, 是该区域盐碱地增加固碳潜力的有效措施。Abstract: Soil organic carbon (SOC) and inorganic carbon (SIC) are important carbon pools involved in the global carbon cycle. Subsurface (10−30 cm) organic ameliorant (OM) combined with film mulching (PM) is an effective measure to optimize the physical structure and regulate water and salt movement of saline soil in arid areas. However, the distribution of SOC and SIC in the 0–60 cm soil layer and their relationship with soil physicochemical properties remain unclear. This study was based on a 6-year micro-field experiment of saline soil at the Yichang Experiment Station, which is located in the Hetao irrigation area of Inner Mongolia. Four treatments were set: conventional control (CK), OM, PM, and OM+PM. The levels of SOC, SIC, total carbon (TC), and soil physicochemical property indexes (soil moisture, salinity, pH, and total nitrogen) in the 0−60 cm (0−20 cm, 20−40 cm, and 40−60 cm) soil layer after the harvest of Helianthus annuus during 2019–2020 were measured, and the variation characteristics and influencing factors of TC, SOC, and SIC were analyzed. The results showed that the TC content in the 0−60 cm soil layer and SOC in the 0−40 cm soil layer were mainly affected by OM treatment compared with PM treatment (P<0.01). The SIC content in the 0−40 cm soil layer was affected by OM treatment (P<0.001), PM treatment (P<0.05, except for the 20−40 cm soil layer in 2019), and their interaction (P<0.001); however, the 40−60 cm soil layer was mainly affected by OM treatment (P<0.05). Compared to CK and PM treatments, OM and OM+PM treatments significantly increased SOC content in the 0−40 cm (0−20 cm and 20−40 cm) soil layer by 31.9%−195.6% (P<0.05), and significantly increased SOC content in the 40−60 cm soil layer by 33.7%−49.4% (P<0.05) only in 2020, but significantly decreased SIC content in the 0−40 cm (0−20 cm and 20−40 cm) by 9.9%−35.0% (P<0.05). Based on the changes in SOC and SIC, compared with CK treatment, OM+PM treatment significantly increased TC content in the 20−60 cm (20−40 cm and 40−60 cm) soil layer in 2019 by 10.4%−39.4% (P<0.05), and the TC content of the 0−20 cm layer in 2020 was significantly increased by 13.0% (P<0.05). The regression analysis results further indicated that the dominant factor of the total carbon pool changed from SIC to SOC with the OM+PM treatment. The results of redundancy analysis showed that soil physicochemical properties were the main factors affecting soil TC, SOC, and SIC (explaining 60.7%−91.9% of the variation), and total nitrogen and pH were the main factors affecting soil TC, SOC, and SIC in the 0−40 cm layer, whereas soil TC, SOC, and SIC in the 40−60 cm layer were mainly affected by salinity and pH. Correlation analysis showed that changes in SOC and SIC were completely opposite. Soil organic carbon was positively correlated with total nitrogen and negatively correlated with salinity and pH (P<0.01). Soil inorganic carbon was negatively correlated with total nitrogen and positively correlated with pH (P<0.01). Therefore, OM combined with PM (OM+PM) could compensate for the loss of SIC and realize carbon accumulation by increasing SOC, which is an effective strategy to increase the carbon sequestration potential of saline soil in this region.
-
Key words:
- Subsurface organic ameliorant /
- Film mulching /
- Saline soil /
- Organic carbon /
- Inorganic carbon
-
图 2 2019—2020年不同亚表层培肥结合地膜覆盖处理下不同土层土壤全碳(a、b)、有机碳(c、d)和无机碳(e、f)含量
CK: 常规对照; OM: 亚表层有机培肥; PM: 地膜覆盖; OM+PM: 亚表层有机培肥+地膜覆盖。不同小写字母表示同一土层不同处理间差异显著(P<0.05)。CK: conventional control; OM: subsurface organic ameliorant; PM: film mulching; OM+PM: subsurface organic ameliorant and film mulching. Different lowercase letters mean significant differences (P<0.05) under different treatments for the same soil layer.
Figure 2. Contents of soil total carbon (TC; a, b), organic carbon (SOC; c, d) and inorganic carbon (SIC; e, f) of different soil layers under different treatments of subsurface organic ameliorant and film mulching in 2019 and 2020
图 3 不同亚表层培肥结合地膜覆盖处理下土壤有机碳(SOC)、无机碳(SIC)及全碳(TC)间相关性分析
CK: 常规对照; OM: 亚表层有机培肥; PM: 地膜覆盖; OM+PM: 亚表层有机培肥+地膜覆盖。实线和阴影区域分别表示线性模型拟合和95%置信区间。CK: conventional control; OM: subsurface organic ameliorant; PM: film mulching; OM+PM: subsurface organic ameliorant and film mulching. The dotted lines and shadow areas indicate linear model fits and 95% confidence intervals, respectively.
Figure 3. Correlation analysis among soil organic carbon (SOC), inorganic carbon (SIC) and total carbon (TC) contents under different treatments of subsurface organic ameliorant and film mulching
图 4 不同亚表层培肥结合地膜覆盖处理下不同土层理化性状与碳含量之间相关性的冗余分析(a, d, g)、土壤理化性状对土壤碳含量变化的解释率(b, e, h)及两者间相关性分析(c, f, i)
CK: 常规对照; OM: 亚表层有机培肥; PM: 地膜覆盖; OM+PM: 亚表层有机培肥+地膜覆盖。TC: 全碳; SOC: 有机碳; SIC: 无机碳; TN: 全氮; Moisture: 含水率; Salt: 盐分。CK: conventional control; OM: subsurface organic ameliorant; PM: film mulching; OM+PM: subsurface organic ameliorant and film mulching. TC: total carbon; SOC: organic carbon; SIC: inorganic carbon; TN: total nitrogen. *: P<0.05; **: P<0.01.
Figure 4. Redundancy analyses (RDA) of the correlations between soil physicochemical properties and carbon content (a, d, g), and the explained rates of soil physicochemical properties on variance of soil carbon (b, e, h), and Pearson correlation among them (c, f, i) of different soil layers under different treatments of subsurface organic ameliorant and film mulching
表 1 2019—2020年不同亚表层培肥结合地膜覆盖处理对不同土层土壤理化性质的影响
Table 1. Soil physicochemical properties of different layers under different treatments of subsurface organic ameliorant and film mulching in 2019 and 2020
理化性质
Physicochemical property处理
Treatment2019 2020 0~20 cm 20~40 cm 40~60 cm 0~20 cm 20~40 cm 40~60 cm 全氮
Total N
(g∙kg−1)CK 0.71±0.01b 0.61±0.03c 0.69±0.03a 0.69±0.06b 0.61±0.04c 0.55±0.05a OM 0.96±0.01a 0.88±0.06b 0.72±0.05a 1.18±0.03a 0.86±0.03b 0.56±0.05a PM 0.79±0.02b 0.65±0.03c 0.72±0.03a 0.69±0.04b 0.63±0.04c 0.56±0.05a OM+PM 0.96±0.05a 1.21±0.05a 0.72±0.05a 1.27±0.01a 1.15±0.03a 0.56±0.05a 含水率
Moisture
(%)CK 9.28±0.14b 13.27±0.06b 14.97±0.25c 13.83±0.36a 14.00±0.09b 14.47±0.44c OM 5.23±0.00c 13.81±0.43b 17.97±0.34a 10.97±0.56b 14.52±0.10b 16.89±0.16a PM 10.50±0.51a 15.80±0.22a 17.33±0.42a 13.19±0.50a 16.25±0.01a 17.51±0.29a OM+PM 4.93±0.14c 10.90±0.52c 16.11±0.36b 11.74±0.07b 10.55±0.31c 15.99±0.12b 含盐量
Salt content
(g∙kg−1)CK 4.43±0.22a 2.58±0.13a 2.13±0.33a 3.59±0.06a 2.28±0.15a 2.65±0.06a OM 3.73±0.12b 2.06±0.21b 2.18±0.12a 2.37±0.08b 2.20±0.11a 2.55±0.04a PM 3.97±0.06ab 2.69±0.12a 2.44±0.12a 3.49±0.00a 2.38±0.04a 2.69±0.10a OM+PM 2.98±0.19c 1.90±0.02b 2.31±0.29a 2.11±0.17b 2.06±0.02a 2.58±0.26a pH CK 8.03±0.04a 8.25±0.00a 8.21±0.05a 7.91±0.07a 8.21±0.11a 8.26±0.03ab OM 7.74±0.11bc 7.62±0.01b 7.90±0.02b 7.67±0.11b 7.55±0.03b 8.14±0.02b PM 7.96±0.08ab 8.12±0.08a 8.10±0.07a 7.98±0.02a 8.17±0.01a 8.29±0.01a OM+PM 7.70±0.03c 7.59±0.05b 7.91±0.03b 7.76±0.05ab 7.31±0.08c 7.97±0.08c CK: 常规对照; OM: 亚表层有机培肥; PM: 地膜覆盖; OM+PM: 亚表层有机培肥+地膜覆盖。不同小写字母表示同一土层不同处理间差异显著(P<0.05)。CK: conventional control; OM: subsurface organic ameliorant; PM: film mulching; OM+PM: subsurface organic ameliorant and film mulching. Different lowercase letters mean significant differences (P<0.05) under different treatments for the same soil layer. -
[1] LAL R, KIMBLE J M, ESWARAN H, et al. Global Climate Change and Pedogenic Carbonates[M]. Boca Raton: CRC Press, 2000 [2] WU H B, GUO Z T, PENG C H. Distribution and storage of soil organic carbon in China[J]. Global Biogeochemical Cycles, 2003, 17(2): 1048 [3] WU H B, GUO Z T, GAO Q, et al. Distribution of soil inorganic carbon storage and its changes due to agricultural land use activity in China[J]. Agriculture, Ecosystems & Environment, 2009, 129(4): 413−4212 [4] SANDERMAN J, BALDOCK J A. Accounting for soil carbon sequestration in national inventories: a soil scientist’s perspective[J]. Environmental Research Letters, 2010, 5(3): 034003 doi: 10.1088/1748-9326/5/3/034003 [5] SANDERMAN J. Can management induced changes in the carbonate system drive soil carbon sequestration: a review with particular focus on Australia[J]. Agriculture Ecosystems & Environment, 2012, 155: 70−77 [6] KIM J H, JOBBÁGY E G, RICHTER D D, et al. Agricultural acceleration of soil carbonate weathering[J]. Global Change Biology, 2020, 26(10): 5988−6002 doi: 10.1111/gcb.15207 [7] LIU S S, ZHOU L H, LI H, et al. Shrub encroachment decreases soil inorganic carbon stocks in Mongolian grasslands[J]. Journal of Ecology, 2020, 108(2): 678−686 doi: 10.1111/1365-2745.13298 [8] RAZA S, MIAO N, WANG P Z, et al. Dramatic loss of inorganic carbon by nitrogen-induced soil acidification in Chinese croplands[J]. Global Change Biology, 2020, 26(6): 3738−3751 doi: 10.1111/gcb.15101 [9] FERDUSH J, PAUL V. A review on the possible factors influencing soil inorganic carbon under elevated CO2[J]. CATENA, 2021, 204: 105434 doi: 10.1016/j.catena.2021.105434 [10] RAZA S, ZAMANIAN K, ULLAH S, et al. Inorganic carbon losses by soil acidification jeopardize global efforts on carbon sequestration and climate change mitigation[J]. Journal of Cleaner Production, 2021, 315: 128036 doi: 10.1016/j.jclepro.2021.128036 [11] KUZYAKOV Y, SHEVTZOVA E, PUSTOVOYTOV K. Carbonate re-crystallization in soil revealed by 14C labeling: Experiment, model and significance for paleo-environmental reconstructions[J]. Geoderma, 2006, 131(1/2): 45−58 [12] MI N, WANG S Q, LIU J Y, et al. Soil inorganic carbon storage pattern in China[J]. Global Change Biology, 2008, 14(10): 2380−2387 doi: 10.1111/j.1365-2486.2008.01642.x [13] ZAMANIAN K, ZAREBANADKOUKI M, KUZYAKOV Y. Nitrogen fertilization raises CO2 efflux from inorganic carbon: a global assessment[J]. Global Change Biology, 2018, 24(7): 2810−2817 doi: 10.1111/gcb.14148 [14] BUGHIO M A, WANG P L, MENG F Q, et al. Neoformation of pedogenic carbonates by irrigation and fertilization and their contribution to carbon sequestration in soil[J]. Geoderma, 2016, 262: 12−19 doi: 10.1016/j.geoderma.2015.08.003 [15] WANG X J, XU M G, WANG J P, et al. Fertilization enhancing carbon sequestration as carbonate in arid cropland: assessments of long-term experiments in northern China[J]. Plant and Soil, 2014, 380(1/2): 89−100 [16] WANG X J, WANG J P, XU M G, et al. Carbon accumulation in arid croplands of Northwest China: pedogenic carbonate exceeding organic carbon[J]. Scientific Reports, 2015, 5: 1−12 doi: 10.9734/JSRR/2015/14076 [17] 李亮, 史海滨, 李和平. 内蒙古河套灌区秋浇荒地水盐运移规律的研究[J]. 中国农村水利水电, 2012(4): 41−44LI L, SHI H B, LI H P. Research on the transport of moisture and salt in the saline land of the Inner Mongolia Hetao Irrigation District[J]. China Rural Water Conservancy and Hydropower, 2012(4): 41−44 [18] 朱姝, 窦森, 陈丽珍. 秸秆深还对土壤团聚体中胡敏酸结构特征的影响[J]. 土壤学报, 2015, 52(4): 747−758ZHU S, DOU S, CHEN L Z. Effect of deep application of straw on composition of humic acid in soil aggregates[J]. Acta Pedologica Sinica, 2015, 52(4): 747−758 [19] ZHANG T A, RUAN H, CHEN H Y. Global negative effect of nitrogen deposition on soil microorganisms[J]. The ISME Journal, 2018, 12(7): 1817−1825 doi: 10.1038/s41396-018-0096-y [20] 张宏媛, 逄焕成, 宋佳珅, 等. 亚表层有机培肥调控盐渍土孔隙结构与水盐运移机制[J]. 农业机械学报, 2022, 53(2): 355−364ZHANG H Y, PANG H C, SONG J S, et al. Effects of pore structure and water-salt movement for saline soil under subsurface organic amendment[J]. Transactions of the Chinese Society for Agricultural Machinery, 2022, 53(2): 355−364 [21] ZHANG H Y, PANG H C, SONG J S, et al. Subsurface organic ameliorant plus polyethylene mulching strengthened soil organic carbon by altering saline soil aggregate structure and regulating the fungal community[J]. Land Degradation & Development, 2022 doi: 10.1002/ldr.4330 [22] ZHANG H Y, LU C, PANG H C, et al. Straw layer burial to alleviate salt stress in silty loam soils: impacts of straw forms[J]. Journal of Integrative Agriculture, 2020, 19(1): 265−276 doi: 10.1016/S2095-3119(19)62737-1 [23] 王巧环, 任玉芬, 孟龄, 等. 元素分析仪同时测定土壤中全氮和有机碳[J]. 分析试验室, 2020, 19(1): 265−276WANG Q H, REN Y F, MENG L. Simultaneous determination of total nitrogen and organic carbon in soil with an elemental analyzer[J]. Chinese Journal of Analysis Laboratory, 2020, 19(1): 265−276 [24] 胡诚, 乔艳, 李双来, 等. 长期不同施肥方式下土壤有机碳的垂直分布及碳储量[J]. 中国生态农业学报, 2010, 18(4): 689−692 doi: 10.3724/SP.J.1011.2010.00689HU C, QIAO Y, LI S L, et al. Vertical distribution and storage of soil organic carbon under long-term fertilization[J]. Chinese Journal of Eco-Agriculture, 2010, 18(4): 689−692 doi: 10.3724/SP.J.1011.2010.00689 [25] ZHAO W, ZHANG R, HUANG C Q, et al. Effect of different vegetation cover on the vertical distribution of soil organic and inorganic carbon in the Zhifanggou Watershed on the Loess Plateau[J]. CATENA, 2016, 139: 191−198 doi: 10.1016/j.catena.2016.01.003 [26] PANT P K, RAM S, BHATT P, et al. Vertical distribution of different pools of soil organic carbon under long-term fertilizer experiment on rice-wheat sequence in mollisols of North India[J]. Communications in Soil Science and Plant Analysis, 2021, 52(3): 235−255 doi: 10.1080/00103624.2020.1859527 [27] GUO Y, WANG X J, LI X L, et al. Dynamics of soil organic and inorganic carbon in the cropland of upper Yellow River Delta, China[J]. Scientific Reports, 2016 doi: 10.1038/srep36105 [28] SU Y Z, WANG X F, YANG R, et al. Effects of sandy desertified land rehabilitation on soil carbon sequestration and aggregation in an arid region in China[J]. Journal of Environmental Management, 2010, 91(11): 2109−2116 doi: 10.1016/j.jenvman.2009.12.014 [29] 黄斌, 王敬国, 金红岩, 等. 长期施肥对我国北方潮土碳储量的影响[J]. 农业环境科学学报, 2006, 25(1): 161−164HUANG B, WANG J G, JIN H Y, et al. Effects of long-term application of fertilizer on carbon storage in calcareous meadow soil[J]. Journal of Agro-Environment Science, 2006, 25(1): 161−164 [30] 曾骏, 郭天文, 包兴国, 等. 长期施肥对土壤有机碳和无机碳的影响[J]. 中国土壤与肥料, 2008(2): 11−14 doi: 10.11838/sfsc.20080203ZENG J, GUO T W, BAO X G, et al. Effects of soil organic carbon and soil inorganic carbon under long-term fertilization[J]. Soil and Fertilizer Sciences in China, 2008(2): 11−14 doi: 10.11838/sfsc.20080203 [31] DONG X L, HAO Q Y, LI G T, et al. Contrast effect of long-term fertilization on SOC and SIC stocks and distribution in different soil particle-size fractions[J]. Journal of Soils and Sediments, 2017, 17(4): 1054−1063 doi: 10.1007/s11368-016-1615-y [32] SHI Y, BAUMANN F, MA Y, et al. Organic and inorganic carbon in the topsoil of the Mongolian and Tibetan grasslands: pattern, control and implications[J]. Biogeosciences, 2012, 9(6): 2287−2299 doi: 10.5194/bg-9-2287-2012 [33] DING F, LI S Y, LÜ X T, et al. Opposite effects of nitrogen fertilization and plastic film mulching on crop N and P stoichiometry in a temperate agroecosystem[J]. Journal of Plant Ecology, 2019, 12(4): 682−692 doi: 10.1093/jpe/rtz006 [34] WANG Y, HU N, GE T. Soil aggregation regulates distributions of carbon, microbial community and enzyme activities after 23-year manure amendment[J]. Applied Soil Ecology, 2017, 111: 65−72 doi: 10.1016/j.apsoil.2016.11.015 [35] TIAN Y F, WANG Q Q, GAO W, et al. Organic amendments facilitate soil carbon sequestration via organic carbon accumulation and mitigation of inorganic carbon loss[J]. Land Degradation & Development, 2022, 33(9): 1423−1433 [36] SUN Z C, QIN W L, WANG X, et al. Effects of manure on topsoil and subsoil organic carbon depend on irrigation regimes in a 9-year wheat-maize rotation[J]. Soil and Tillage Research, 2021, 205: 104790 doi: 10.1016/j.still.2020.104790 [37] GE T D, LUO Y, SINGH B P. Resource stoichiometric and fertility in soil[J]. Biology and Fertility of Soils, 2020, 56(8): 1091−1092 doi: 10.1007/s00374-020-01513-5 [38] PROMMER J, WALKER T W, WANEK W, et al. Increased microbial growth, biomass, and turnover drive soil organic carbon accumulation at higher plant diversity[J]. Global Change Biology, 2020, 26(2): 669−681 doi: 10.1111/gcb.14777 [39] YANG Y, CHEN X L, LIU L X, et al. Nitrogen fertilization weakens the linkage between soil carbon and microbial diversity: a global meta-analysis[J]. Global Change Biology, 2022, 28(21): 6446−6461 doi: 10.1111/gcb.16361 [40] WANG H, FENG D, ZHANG A Q, et al. Effects of saline water mulched drip irrigation on cotton yield and soil quality in the North China Plain[J]. Agricultural Water Management, 2022, 262: 107405 doi: 10.1016/j.agwat.2021.107405 [41] CHEN Q Y, HU Y L, HU A, et al. Shifts in the dynamic mechanisms of soil organic matter transformation with nitrogen addition: from a soil carbon/nitrogen-driven mechanism to a microbe-driven mechanism[J]. Soil Biology and Biochemistry, 2021, 160: 108355 doi: 10.1016/j.soilbio.2021.108355 [42] ZHANG H Y, PANG H C, LU C, et al. Subsurface organic amendment plus plastic mulching promotes salt leaching and yield of sunflower[J]. Agronomy Journal, 2019, 111(1): 457−466 doi: 10.2134/agronj2018.02.0097 [43] WONG V N L, GREENE R S B, DALAL R C, et al. Soil carbon dynamics in saline and sodic soils: a review[J]. Soil Use and Management, 2010, 26(1): 2−11 doi: 10.1111/j.1475-2743.2009.00251.x [44] CHEN B Q, LIU E K, TIAN Q Z, et al. Soil nitrogen dynamics and crop residues: a review[J]. Agronomy for Sustainable Development, 2014, 34(2): 429−442 doi: 10.1007/s13593-014-0207-8 [45] RABENHORST M C, WILDING L, WEST L T. Identification of pedogenic carbonates using stable carbon isotope and microfabric analyses[J]. Soil Science Society of America Journal, 1984, 48: 125−132 doi: 10.2136/sssaj1984.03615995004800010023x -