江苏省农牧系统氮素流动特征及环境效应评价

余乐; 焦阳湄; 丁尚; 朱治强; 赵洪伟

doi:10.13930/j.cnki.cjea.210172

江苏省农牧系统氮素流动特征及环境效应评价

doi: 10.13930/j.cnki.cjea.210172

余乐^1,,
焦阳湄²,
丁尚³,
朱治强²,
赵洪伟^3, ,

1.
江苏农牧科技职业学院　泰州　225300
2.
海南大学热带作物学院　海口　570228
3.
海南大学生态与环境学院　海口　570228

基金项目: 国家自然科学基金项目(41867025)、江苏省“青蓝工程”优秀教学团队(苏教师函[2020]10号)、江苏省现代农业(花卉)产业技术体系泰州推广示范基地(JATS[2020]350)、校级横向课题配套项目(NSFHP201911)和海南省重大科技项目(ZDKJ2017002)资助

详细信息

作者简介:
余乐, 主要从事养分资源管理研究。E-mail: 19870869@qq.com

通讯作者:
赵洪伟, 主要研究方向为污染生态学和生态循环农业。E-mail: hwzhao@hainanu.edu.cn

中图分类号: X2; X171
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出版历程
- 收稿日期: 2021-03-22
- 录用日期: 2021-07-01
- 网络出版日期: 2021-08-19
- 刊出日期: 2021-10-01

Characteristics and environmental effects of nitrogen flows in the crop-livestock system of Jiangsu Province

1.
Jiangsu Agri-animal Husbandry Vocational College, Taizhou 225300, China
2.
College of Tropical Crops, Hainan University, Haikou 570228, China
3.
College of Ecology and Environment, Hainan University, Haikou 570228, China

Funds: This study was supported by the National Natural Science Foundation of China (41867025), the Excellent Teaching Team and Blue Project of Jiangsu Province (Letter from Jiangsu Teachers [2020]10), Taizhou Extension and Demonstration Base of Modern Agricultural (Flower) Industrial Technology System in Jiangsu Province (JATS[2020]350), the Horizontal Project in the Level of School (NSFHP201911) and the Key Science and Technology Program of Hainan Province (ZDKJ2017002)

More Information

Corresponding author: E-mail: hwzhao@hainanu.edu.cn

摘要

摘要: 针对农牧业快速发展过程中氮素大量投入引起的一系列问题, 本文以江苏省为研究对象, 探讨1998—2018年农牧系统氮素流动特征及其环境效应, 以期为区域氮素资源管理提供科学参考。研究基于食物链养分流动模型(NUtrient flows in Food chains, Environment and Resources use, NUFER), 结合统计年鉴数据、调研数据和文献数据, 定量分析江苏省农牧系统氮素账户平衡、各系统氮素利用效率、氮素循环利用和损失情况, 并基于结构方程模型探讨农牧系统中经济-资源-环境间的关系。1998—2018年, 江苏省作物子系统在系统氮素总输入逐步减少的情况下实现了产品携出氮素的较大增长, 作物主副产品氮素携出量由8.31×10⁵ t增至1.20×10⁶ t, 氮素损失总量也在不断降低。对于畜禽子系统, 氮素输入主要包括外源饲料和本地饲料输入, 其中外源饲料是子系统的主要氮素来源; 且本地饲料氮素供给比例在逐年上升, 从1998年的29.32%增长至2018年的44.77%。1998—2018年, 农牧系统氮素利用率由21.39%增至35.00%, 呈上升趋势, 本地饲料、秸秆还田和粪尿还田氮素量逐年上升, 氮素资源循环利用总量由2.54×10⁵ t增至3.00×10⁵ t。从氮素排放损失来看, 20多年来环境排放部分呈下降趋势, 其主要损失途径包括土壤氮素盈余、气体排放损失、水体排放损失和粪污残余损失。结构方程模型核算结果表明江苏省农牧系统的发展过程中, 经济发展和资源减量推动了产品产量和系统效率的提高。总的来说, 受区域发展水平和政策引导, 1998—2018年江苏省农牧体系发展较快, 规模不断扩大, 资源利用相对高效, 环境排放逐渐减少; 但农牧子系统之间的发展不平衡, 农牧结合体系规模相对较小等问题仍值得关注。因此, 今后江苏省农牧业的发展应注重作物子系统和畜牧子系统的耦合, 适度扩大生产规模, 以促进本地农牧业更好发展。
- 江苏省 /
- 农牧系统 /
- 氮素流动 /
- NUFER模型 /
- 环境效应
Abstract: With the rapid development of agriculture and animal husbandry, large nitrogen inputs have caused a series of environmental problems. To provide a scientific reference for regional nutrient management, Jiangsu Province, an economically developed region in the Yangtze River Delta, was selected to study the nitrogen flow characteristics in crop-livestock systems from 1998 to 2018 and their environmental effects. The research was based on the NUFER model (NUtrient flows in Food chains, Environment and Resources use, NUFER) and incorporated statistical yearbook data, survey data, and literature data. The nitrogen account balance, nitrogen use efficiency, nitrogen recycling, and loss of the crop-livestock systems in Jiangsu Province were quantitatively analyzed, and the relationships between the economy, resources, and environment of the crop-livestock systems were explored based on a structural equation model. The results showed that from 1998 to 2018, the crop subsystem increased the amount of nitrogen carried by the crop products under the gradual decrease of the total nitrogen imports of the subsystem. Nitrogen carried by the main crops and crop by-products increased from 8.31×10⁵ t to 1.20×10⁶ t. Total nutrient loss also declined. For the livestock-poultry subsystem, nitrogen was mainly introduced via exogenous and local feed; exogenous feed was the main source of nitrogen in the subsystem. The proportion of local feed nitrogen supply increased annually, from 29.32% in 1998 to 44.77% in 2018. From 1998 to 2018, the nitrogen use efficiency of the crop-livestock system increased from 21.39% to 35.00%. The amount of straw to field, local feed, and manure to field increased annually, and the total amount of recycled nitrogen increased from 2.54×10⁵ t to 3.00×10⁵ t. Nitrogen environmental emissions decreased in the past 20 years, and the main sources of loss included soil nitrogen surplus, gas emission loss, water discharge loss, and manure residue. The structural equation model results showed that in the developmental process of the agricultural and animal husbandry systems in Jiangsu Province, economic development and resource reduction promoted improvements in product output and system efficiency. Under the guidance of regional development and policies, crop-livestock systems in Jiangsu Province developed rapidly from 1998 to 2018. The scale of the agricultural and animal husbandry systems had continuously expanded, resource utilization had been relatively efficient, and environmental emissions had gradually decreased. However, there was also a slight imbalance in the development of crop-livestock systems, and there were relatively few combinations of crop-livestock. Future development of the agriculture and animal husbandry systems in Jiangsu Province should focus on coupling the crop and animal husbandry subsystems, moderately expanding the production scale, and balancing the development of agriculture and animal husbandry subsystems to promote local agriculture and animal husbandry.
- Jiangsu Province /
- Crop-livestock system /
- Nitrogen flows /
- NUFER model /
- Environmental effects

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图 1 农牧系统氮素流动模型简图

Figure 1. Schematic diagram of nitrogen flows model in the crop-livestock system

下载: 全尺寸图片幻灯片

图 2 1998—2018年江苏省作物子系统(a)和畜禽子系统(b)的氮素流动变化

图中横坐标以上部分为氮素输入各项, 横坐标以下部分为氮素输出各项。In the figure, the above part of the abscissa is N input items, and the below part of the abscissa is N output items.

Figure 2. N flows changes in the crop subsystem (a) and livestock subsystem (b) from 1998 to 2018 in Jiangsu Province

下载: 全尺寸图片幻灯片

图 3 1998—2018年江苏省农牧系统氮素利用效率(a)、氮素循环利用率(b)和氮素损失情况(c)

NUEc: N use efficiency of crop subsystem; NUEa: N use efficiency of livestock subsystem; NUEa+c: N use efficiency of crop-livestock system.

Figure 3. N use efficiency (a), N cycle utlization rate (b) and N loss (c) in the crop-livestock system of Jiangsu Province from 1998 to 2018

下载: 全尺寸图片幻灯片

图 4 江苏省农牧体系结构方程模型建模结果示意图

图中实线部分表示社会需求(居民人均收入和氮素总携入)、系统发展(系统效率和主产品携出)与环境效应(气体损失、水体排放和其他途径损失)间的关系, 粗实线表示具有正效应, 细实线表示具有负效应; 虚线部分为社会需求和系统发展间的关系; 数值部分为标准化路径系数; **表示P<0.01, *表示P<0.05, R为相关系数值。The solid line shows the relationship between social demand (income per capita and total nitrogen input), system development (system efficiency and main product output) and environmental effect (gas loss, water discharge and other route loss). The thick solid line shows positive effect and the thin solid line shows negative effect. The dotted line shows the relationship between social demand and system development. The numerical part is the standardized path coefficient. ** means P<0.01, * means P<0.05, and R is the correlation value.

Figure 4. Schematic diagram of structural equation modeling results of the crop-livestock system in Jiangsu Province

下载: 全尺寸图片幻灯片

表 1 作物子系统中氮素损失去向和损失比例

Table 1. The direction and proportion of N loss in the crop subsystem

项目 Item		参数 Parameter	项目 Item		参数 Parameter
输入项 Imports	生物固氮^[24] Biological N fixation^[24]	19 kg(N)∙hm⁻²	输出项 Outputs	NH₃^[33]	15.0%
	生物固氮^[24] Biological N fixation^[24]	19 kg(N)∙hm⁻²		N₂O^[33]	1.0%
	大气氮沉降^[24] N deposition^[24]	33 kg(N)∙hm⁻²		反硝化^[33] Denitrification^[33]	15.0%
	大气氮沉降^[24] N deposition^[24]	33 kg(N)∙hm⁻²		径流^[10] Runoff^[10]	15.8%
	灌溉水氮携入^[29] Irrigation^[29]	5.2 kg(N)∙hm⁻²		侵蚀^[10] Erossion^[10]	0.7%
	灌溉水氮携入^[29] Irrigation^[29]	5.2 kg(N)∙hm⁻²		淋溶^[10] Leaching^[10]	18.8%

下载: 导出CSV

表 2 主要动物活体养殖信息和产品含氮量^[24]

Table 2. Breeding information and N content of products of animals^[24]

畜禽种类 Animal category	鲜重 Fresh weight (kg)	养殖周期 Days (d)	分配系数 Distribution coefficient (%)			氮素含量 N content (%)
畜禽种类 Animal category	鲜重 Fresh weight (kg)	养殖周期 Days (d)	可食用比例 Ratio of edible part	骨头比例 Ratio of bones	其他 Ratio of by-products	可食用部分 Edible part	骨头部分 Bones	其他 By-products
猪 Pig	90	199	50	13	37	1.5	1.9	2.2
奶牛 Dairy cattle	624	>365	45	20	35	2.8	1.8	2.2
肉牛 Beef cattle	316	>365	45	20	35	2.8	1.8	2.2
役用牛 Draft cattle	328	>365	45	20	35	2.8	1.8	2.2
羊 Sheep	35	243	55	24	21	2.1	1.9	2.2
肉禽 Poultry	2	60	65	20	15	2.7	2.6	1.5

下载: 导出CSV

表 3 主要畜禽粪污氮素产生量和氮素损失比例^[30-32]

Table 3. N production and loss ratio of livestock and poultry manure^[30-32]

畜禽种类 Animal category	氮素产生量 N production (g·d⁻¹)	NH₃ (%)	N₂O (%)	反硝化 Denitrification (%)	无序排放 Other emission
猪 Pig	20.76	28	2.0	5.0	32.5
奶牛 Dairy cattle	214.51	21	4.0	5.0	24.5
肉牛 Beef cattle	153.47	21	4.0	5.0	24.5
役用牛 Draft cattle	107.77	21	4.0	5.0	24.5
羊 Sheep	2.15	25	1.0	5.0	53.1
肉禽 Poultry	1.02	22	1.0	5.0	39.6

下载: 导出CSV

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