| 摘要: |
| 【目的】我国农业大国基础地位决定了在较长时期内，需要维持相对较高水平化肥投入和农业用水占比，才能保障国家粮食和农产品安全，但潜在的农田面源污染问题不容忽视。【方法】基于化肥施用量、农田氮磷面源污染排放系数和农业用水量等数据，分析了农田尾水质量及其对地表水质量的影响。【结果】从2015年化肥施用量开始下降，至2019年氮肥和磷肥分别降低了13.7%和9.1%；农业用水占比从2012年开始降低，2019年降低了2.2%；2007-2017年期间，农田氮污染排放系数从5.7%降低至2.4%，农田磷污染排放系数从0.9%降低至0.5%；地表水环境质量显著改善和稳定趋好，2018年较2009年，河流Ⅳ+Ⅴ类水质占比降低了40.8%，劣Ⅴ类水质占比降低了71.5%。【结论】全域尺度下的农田面源污染防治取得了巨大成效，农作物产量不减反增。我国农田尾水属于劣Ⅴ类水质，对地表水环境质量的潜在影响较大，尤其在局部地区或部分流域段。但从全域尺度看，农田面源污染TN和TP对地表水环境质量的整体影响有限，2017年以后，呈现显著降低趋势。农田面源污染的关注重点应转移到局部地区和部分流域段，以逐步提升地表水环境质量。 |
| 关键词: 全域尺度；农田面源污染；水环境质量；影响 |
| DOI： |
| 分类号:S273；X52 |
| 基金项目: |
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| Effects on water environment quality of non-point source pollution from farmland based on national scale |
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Yang
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中国农业科学院农业环境与可持续发展研究所
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| Abstract: |
| 【Objective】The fundamental?status?of Chinese?large?agricultural?country has to maintain a relative higher level fertilizer application and ratio of agricultural water in a long period, so national food and other agricultural products security could be guaranteed, but these problems from non-point source pollution of farmland should be pain close attention in long-term. 【Method】Based on the data of fertilizer application amount, nitrogen and phosphorus non-point source pollution emission coefficient and agricultural water consumption, the quality of farmland tail water and its influence on surface water quality were analyzed. 【Results】The ratio of fertilizer application decreased from 2015, which nitrogen fertilizer and phosphorus fertilizer were reduced 13.7% and 9.1% in 2019, respective. Agricultural water decreased from 2012, which the ration of agricultural water was reduced 2.2% in 2019. In the period of 2007-2017, emission factors of farmland nitrogen pollution was reduced from 5.7% to 2.4%, and emission factors of farmland phosphorus pollution was reduced from 0.9% to 0.4. The environmental quality of surface water has been improved significantly and gotten better steadily, which ratio of class Ⅳ+Ⅴof river was reduce 40.8% and interior class Ⅴwas reduced 17.4% in 2018 according to 2009. Non-point source pollution of farmland control had achieved a great progress and crop yields rose up,?not?down. Agricultural waters all belong to interior class inⅤChina, which have a potential effects on surface water quality, especially in local area or parts of basin. 【Conclusion】On a national scale, effects on surface water quality of total nitrogen and total phosphorus pollution from non-point source pollution of farmland are limited and it showed a significant decreasing trend after 2017. The key of NPF should pay attention to local areas and some river basins, so surface water environmental quality were gradually improved. |
| Key words: national scale; non-point source pollution from farmland(NPF); water environment quality; effect |
