摘要
无锡市20年来施肥量不断增加,但氮、磷用量较多,钾肥使用较少。无锡市区、江阴市、宜兴市土壤氮、磷含量分别增长0.06～0.48gkg-1和0.06～0.17gkg-1,无锡市区稻田土壤速效钾含量基本没有变化,但江阴市、宜兴市速效钾含量明显降低。随着城镇化进程加快,1999年以来无锡农业生产结构产生较大变化,蔬菜等经济作物种植比例越来越大。典型区土壤养分输入-输出平衡的监测结果表明,单位面积菜地氮的盈余量是稻田的6倍以上,磷的盈余量是稻田的100倍以上,但菜地和稻田的钾素均不断亏缺。稻田土壤转变为菜地土壤后,土壤剖面0～50cm范围内发生明显的氮素和磷素积聚,土壤pH降低。通过释放多余的氮、磷,土壤可能对周围环境产生长期持续的不良影响。
The fertilizer application amount increased steadily in the past 20 years in Wuxi, but there was a disproportion among nitrogen, phosphorus and potassium. The nitrogen and phosphorus fertilizers were applied excessively while potassium fertilizer was not enough, which caused nitrogen, phosphorus increased 0.06-0.48g kg^-1 and 0.06-0.17g kg^-1 respectively in paddy soils of Wuxi urban district, Jiangyin and Yixing countries. Available potassium in paddy soils of Wuxi urban district kept no change, but decreased significantly in paddy fields of Jiangyin and Yixing. With the urbanization rate increased, the agricultural production structure in Wuxi has changed greatly since 1999, and the area proportion of cash crops, e.x. vegetable, increased successively. On the basis of nutrient balance, surplus amount of nitrogen and phosphorus in vegetable soil was 6 times and 100 times respectively of that in paddy field, while the potassium in soils of both types of land was inadequate. Compared with the soil properties of a proximity paddy plot, nitrogen and phosphorus accumulated and soil pH decreased significantly in 0-50cm soil of vegetable plots. It could be concluded that the environment risk caused by nitrogen and phosphorus released from soil increased.
出处
《土壤通报》
CAS
CSCD
北大核心
2009年第2期297-301,共5页
Chinese Journal of Soil Science
基金
国家自然科学基金项目(40671012)
国家自然科学青年基金(40801080)
欧盟项目(RURBIFARM
Contract No:ICA4-CT-2002-10021)
河南省教育厅自然科学基础研究计划项目(2007210036)资助
关键词
施肥变化
土壤属性演变
太湖流域
Fertilizer application
Soil properties evolution
Taihu Lake Region
