摘要
【目的】定量研究天然草地的氮磷流动空间特征,为优化牧草施肥和提高牧草产量提供科学依据。【方法】建立中国天然草地氮磷养分输入(输出)数据库,利用NUFER模型定量中国天然草地氮磷平衡账户、利用率和环境排放特征。【结果】(1)2013年,全国天然草地氮和磷的输入(输出)总量分别为5 034 Gg N和318 Gg P,单位面积的输入(输出)量分别为19 kg N·hm^(-2)和1.2 kg P·hm^(-2)。氮沉降和畜禽粪尿磷分别占氮和磷输入总量的49%和89%。各区域天然草地氮和磷输入(输出)量变化范围分别为7.0—70 kg N·hm^(-2)和0.12—8.0 kg P·hm^(-2);(2)2013年,天然草地氮和磷养分利用率分别为105%和191%,各区域间差异很大。中国各地区天然草地的氮利用率变化范围为67%—141%,磷利用率的变化范围为75%—538%;(3)2013年,天然草地氮和磷的环境损失量分别为1.7 kg N·hm^(-2)和0.059 kg P·hm^(-2),氨挥发和侵蚀分别是氮和磷的主要损失途径。西南和东北地区天然草地氮损失量较多,部分区域的损失量超过8.0 kg N·hm^(-2);西北地区氮损失量较少,平均不足3.0 kg N·hm^(-2);青藏高原区氮损失量最少,不足1.0 kg N·hm^(-2)。磷的环境排放空间规律与氮排放相似;(4)2013年,全国天然草地土壤氮和磷的亏缺总量分别为706 Gg N和315 Gg P,单位面积亏缺量分别为2.7 kg N·hm^(-2)和1.2 kg P·hm^(-2)。北方和西南部分地区天然草地的氮土壤累积量为负值,重庆、吉林和辽宁的土壤氮亏损量超过20 kg N·hm^(-2);西部和西南部分省份天然草地的氮土壤累积量为正值,其中广西和云南的土壤氮累积量超过5.0 kg N·hm^(-2)。除广西和贵州外,其他区域天然草地磷养分均有不同程度的亏缺,重庆天然草地磷的亏缺量最大,为3.7 kg P·hm^(-2)。【结论】2013年,全国天然草地的氮和磷输入量较小,约50%的氮素通过氮沉降输入系统,约90%的磷素通过畜禽粪尿磷输入系统;全国天
【Objective】The objective of this study is to quantify the spatial characteristics of nitrogen（N） and phosphorus（P） flow in natural grassland of China, and to provide a scientific basis for optimizing forage fertilization and increasing forage yield. 【Method】The input and output database of N and P in natural grassland of China was established, the nutrient balance budget, nutrient use efficiency and environmental emission characteristics in natural grassland of China were quantified by using NUFER model. 【Result】（1） In 2013, the total input of N and P in natural grassland of China was 5 034 Gg N and 318 Gg P, respectively. The N and P input per unit area in natural grassland was 19 kg N·hm-2 and 1.2 kg P·hm-2, respectively. The N deposition and the manure P applied accounted for 49% and 89% of total N and P input. The range of input（output） of N and P in natural grassland in different regions was 7.0-70 kg N·hm-2 and 0.12-8.0 kg P·hm-2;（2） In 2013, the use efficiency of N and P in natural grassland of China was 105% and 191%, respectively. There were great differences among different regions. The range of use efficiency of N and P was 67%-141%, 75%-538%, respectively;（3） In 2013, the environmental loss of N and P in natural grassland of China was 1.7 kg N·hm-2 and 0.059 kg P·hm-2, respectively. Ammonia emission and erosion were the main loss pathways of N and P in natural grassland, respectively. The N loss in natural grassland of Southwest and Northeast China was over 8.0 kg·hm-2. The N loss of Northwest China was relatively low, which was less than 3.0 kg·hm-2 on average. The N loss in Tibet plateau was the lowest, which was less than 1.0 kg·hm-2. Spatial regularity of environmental P emission was similar to that of N emission;（4） In 2013, the total N and P deficit in natural grassland of China was 706 Gg N and 315 Gg P, respectively. The deficit per unit area of N and P was 2.7 kg N·hm-2 and 1.2 kg P·hm-2, respectively. The value of soil N accumulation in Nort
出处
《中国农业科学》
CAS
CSCD
北大核心
2018年第3期523-534,共12页
Scientia Agricultura Sinica
基金
国家重点研发计划(2016YFD0800106
2016YFD0200105)
国家自然科学基金面上项目(31572210)
河北省杰出青年基金(D2017503023)
中国科学院百人计划项目
关键词
天然草地
氮
磷
养分流动
养分利用率
土壤养分累积
natural grassland
nitrogen
phosphorus
nutrient flow
nutrient use efficiency
soil nutrient accumulation
