Soil nitrate accumulation and leaching to groundwater during the entire vegetable phase following conversion from paddy rice
Soil nitrate accumulation and leaching to groundwater during the entire vegetable phase following conversion from paddy rice
复制标题
DOI：
10.1007/s10705-016-9807-9
复制
发表时间：
2016-10
影响因子：
3.1
通讯作者：
Y. Wang;Kunzhi Li;Takashi S. T. Tanaka;Dan Yang;Tastuya Inamura
中科院分区：
文献类型：
--
作者：
Y. Wang;Kunzhi Li;Takashi S. T. Tanaka;Dan Yang;Tastuya Inamura
在中国，大量农田从传统的谷物种植转为密集的蔬菜种植，造成了环境风险。以往的研究利用了几种方法来估计集约化蔬菜种植下土壤中硝酸盐的积累和淋溶到地下水中，例如比较集约化种植与非集约化种植，或调查短期内（如1或2年）土壤硝酸盐的季节动态。本研究试图利用一种不同的方法，考虑从传统的粮食作物种植转换后的整个蔬菜种植阶段（长达9年）的总氮（N）输入对土壤和地下水的影响。在研究区进行了大规模的调查。蔬菜，土壤和地下水样品收集了22个领域。结果表明，在整个蔬菜种植期内，土壤硝态氮与化肥全氮输入量呈显著正相关，地下水硝态氮与土壤硝态氮呈显著正相关。45%的威尔斯水井中的硝酸盐浓度超过了饮用水最高污染水平10 mg L−1。这些结果表明，该地区土壤硝态氮的积累是由于长期大量施用氮化肥，而不是来自有机肥。此外，高灌溉水平导致土壤中积累的硝酸盐渗入地下水，造成地下水的硝酸盐污染。
Large amounts of farmland have been converted from traditional cereal cropping to intensive vegetable cropping in China, creating environmental risks. Previous studies utilized several methods of estimating nitrate accumulation in soil and leaching to groundwater under intensive vegetable cultivation, such as comparing intensive cropping to non-intensive cropping, or investigating the seasonal dynamics of soil nitrates in the short term, such as 1 or 2 years. This study tried to utilize a different method, considering the effects of total nitrogen (N) input during the whole vegetable cropping phase (up to 9 years) after conversion from traditional cereal cropping on soil and groundwater. A large-scale investigation was performed in the study area. Vegetable, soil, and groundwater samples were collected from 22 fields. Results showed that soil nitrate was significantly correlated with total N input from chemical fertilizer during the whole vegetable cropping phase, and groundwater nitrate was significantly correlated with soil nitrate. Nitrate concentration in 45 % of wells exceeded the drinking water maximum contaminant level, 10 mg L−1. These results suggest that soil nitrate accumulation in the area resulted from long-term application of large amounts of N chemical fertilizer, and not from manure. Furthermore, high irrigation levels caused the accumulated nitrate in soil to leach into the groundwater, resulting in nitrate contamination of the groundwater.