[2001年至2021年河南省农业非点源污染的空间和时间分布特征和来源分析]
Zhen-Feng Zang1, Su-Hua Liu1, Yong-Hua Li2
1Henan Key Laboratory of Water Resources Conservation and Intensive Utilization in the Yellow River Basin, College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou 450046, China.
Huan jing ke xue= Huanjing kexue
|February 9, 2026
概括
河南省农业非点源污染显示化学氧需求 (COD) 和总 (TN) 的下降趋势,但从2001年到2021年,总 (TP) 的增加趋势. 畜牧业和肥料使用是污染的主要来源,需要有针对性的控制策略.
科学领域:
- 环境科学 环境科学
- 农业科学 农业科学
- 水质管理水质管理
背景情况:
- 农业非点源污染对中国水体构成重大威胁,特别是在河南省等主要粮食生产地区.
- 不合理使用农药和化肥加剧了污染,影响了水环境和生态安全.
研究的目的:
- 估计河南省 (2001-2021) 农业非点源的化学氧需求 (COD),总 (TN) 和总 (TP) 的污染负荷.
- 分析这些污染物的空间和时间分布特征和排放强度.
- 确定导致农业非点源污染的主要来源.
主要方法:
- 从2001年到2021年,使用库存分析来量化污染负载 (COD,TN,TP).
- 阐明了污染负载和排放强度的空间和时间分布模式.
- 进行了来源分配,以确定污染的主要贡献者.
主要成果:
- 时间趋势 (2001-2021) 显示COD和TN负载/强度下降,但TP负载/强度增加.
- 污染负载表现出空间聚类,高值集中在河南南部 (南阳,朱马迪安,新疆) 和东部 (长春,周口) 河南. 排放强度因地区而异,在东部和北部通常更高.
- 牲畜和家禽养殖是COD的主要来源,而化学肥料和畜牧业对TN和TP的贡献最大. 南阳,朱马迪安和周口是主要的贡献地区.
结论:
- 河南的农业非点源污染显示出明显的时间转移和显著的空间差异.
- 对于污染风险管理,建议采用双重控制策略 ("负载控制-强度约束").
- 促进降低肥料,利用肥料和管理草资源对于减轻污染至关重要.
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