The net anthropogenic nitrogen input(NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessme...The net anthropogenic nitrogen input(NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessment and management.This paper calculated NANI in the upper Yangtze River basin(YRB), upstream of the Three Gorges Dam(TGD), from1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km^(-2) to 4931 kg N km^(-2). The major components were fertilizer N application, atmospheric N deposition,and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir.展开更多
为解析中国人为净氮输入(NANI)和人为净磷输入(NAPI)的来源和空间分布,本研究构建了中国市域NANI和NAPI模型,核算了2020年中国367个市域单元NANI和NAPI,并采用标准差椭圆方程和莫兰指数对其进行空间异质性分析。主要结论为:①2020年中国...为解析中国人为净氮输入(NANI)和人为净磷输入(NAPI)的来源和空间分布,本研究构建了中国市域NANI和NAPI模型,核算了2020年中国367个市域单元NANI和NAPI,并采用标准差椭圆方程和莫兰指数对其进行空间异质性分析。主要结论为:①2020年中国NANI和NAPI分别为4596.43 kg N/(km^(2)·a)和840.02 kg P/(km^(2)·a);②化肥施用是NANI和NAPI的主要贡献源,其中80.93%、89.65%的市域单元分别为其最大贡献源;③中国NANI和NAPI空间分布具有明显的聚集性和异质性,以胡焕庸线为界,东南部地区的NANI和NAPI明显高于西北部,聚集区域主要分布在华北平原地区。NANI和NAPI模型是一种定量评估区域内氮磷排放状态的模型,能够为中国氮磷污染重点区域的识别、污染治理等提供技术支撑。展开更多
由人类活动产生的氮排放是影响河流氮通量输出的关键,本研究基于人类活动净氮输入模型和流域分布式水文模型(SWAT),计算了山美水库流域2001—2010年人为氮排放强度,模拟估算了同期的河流氮通量,对山美水库河流氮输出与人类活动净氮输入(...由人类活动产生的氮排放是影响河流氮通量输出的关键,本研究基于人类活动净氮输入模型和流域分布式水文模型(SWAT),计算了山美水库流域2001—2010年人为氮排放强度,模拟估算了同期的河流氮通量,对山美水库河流氮输出与人类活动净氮输入(NANI)之间的响应特征进行研究。结果表明,2001—2010年间,山美水库流域年均人类活动净氮输入强度为11 023 kg N·km^(-2),其中氮肥施用量占NANI总量的60%,是NANI的主要来源;河流氮通量的年际变化特征深受河流年径流变化影响,与NANI并无显著相关;NANI、滞留氮库以及自然背景源对流域河流氮输出总量的贡献率分别达到52%、44%和4%,包括NANI和滞留氮库在内的人为氮输入是影响山美水库流域河流氮通量输出的关键因素。展开更多
基金supported by the Basic Research Fund Program of the State key Laboratory of Hydroscience and Engineering (Grant Nos. 2014-KY-04 & 2013-KY-03)
文摘The net anthropogenic nitrogen input(NANI) is an important nutrient source that causes eutrophication in water bodies. Understanding the spatio-temporal variation of NANI is important for regional environment assessment and management.This paper calculated NANI in the upper Yangtze River basin(YRB), upstream of the Three Gorges Dam(TGD), from1990 to 2012, and analyzed its spatio-temporal characteristics. Over the past 23 years of the study, the average annual NANI increased from 3200 kg N km^(-2) to 4931 kg N km^(-2). The major components were fertilizer N application, atmospheric N deposition,and net food and feed N import. In the northwest high mountainous region with a sparse population, the main component was atmospheric N deposition. Fertilizer N application and net food and feed N import were concentrated in the Chengdu Plain because of the high population density and large areas of farmland. This research found that NANI increased with rapid urbanization and increasing population. The Pearson correlation results illustrated that the spatial distributions of NANI and its major components were affected by land cover/use, agricultural GDP and total population. Increasing NANI has been the major cause of the degrading stream water quality over the past 20 years and is becoming a major threat to the water quality of the TGD reservoir.
文摘为解析中国人为净氮输入(NANI)和人为净磷输入(NAPI)的来源和空间分布,本研究构建了中国市域NANI和NAPI模型,核算了2020年中国367个市域单元NANI和NAPI,并采用标准差椭圆方程和莫兰指数对其进行空间异质性分析。主要结论为:①2020年中国NANI和NAPI分别为4596.43 kg N/(km^(2)·a)和840.02 kg P/(km^(2)·a);②化肥施用是NANI和NAPI的主要贡献源,其中80.93%、89.65%的市域单元分别为其最大贡献源;③中国NANI和NAPI空间分布具有明显的聚集性和异质性,以胡焕庸线为界,东南部地区的NANI和NAPI明显高于西北部,聚集区域主要分布在华北平原地区。NANI和NAPI模型是一种定量评估区域内氮磷排放状态的模型,能够为中国氮磷污染重点区域的识别、污染治理等提供技术支撑。
文摘由人类活动产生的氮排放是影响河流氮通量输出的关键,本研究基于人类活动净氮输入模型和流域分布式水文模型(SWAT),计算了山美水库流域2001—2010年人为氮排放强度,模拟估算了同期的河流氮通量,对山美水库河流氮输出与人类活动净氮输入(NANI)之间的响应特征进行研究。结果表明,2001—2010年间,山美水库流域年均人类活动净氮输入强度为11 023 kg N·km^(-2),其中氮肥施用量占NANI总量的60%,是NANI的主要来源;河流氮通量的年际变化特征深受河流年径流变化影响,与NANI并无显著相关;NANI、滞留氮库以及自然背景源对流域河流氮输出总量的贡献率分别达到52%、44%和4%,包括NANI和滞留氮库在内的人为氮输入是影响山美水库流域河流氮通量输出的关键因素。
