不同水质灌溉下绿地养分积累及其比较

Accumulation and comparison of greenbelt nutrients under different water irrigating ways

对天津泰达开发区的清水、清水和处理水混合水、处理水灌溉区进行土壤和植物调查研究,分析不同水质灌溉下土壤、植物中养分含量的变化,发现混水、处理水灌溉土壤中全氮、有机质、pH值增加不明显,部分甚至有下降趋势,但水解氮、速效磷、速效钾在混水和处理水灌溉土壤中均增加显著.植物叶中氮、磷、钾含量变化较小,与土壤中的相应元素没有表现出相关性,说明混水和处理水中的养分并没有为植物有效利用.对土壤不同层上的养分研究表明,长期灌溉混水或处理水后,除有机质外,其他养分易于向下迁移,使不同层上没有表现出明显差异.

During the research of soil and plants which were irrigated by three types of water （tap water, mixed water of tap and treated water, treated water） in Teda Economic-technological Development Area of Tianjin, the authors analyzed the accumulation of nutrients concentration in soil and plants. Results showed that total nitrogen, organic matter, and pH didn＇t increase evidently and some of them even had decreasing trend. But hydrolysable nitrogen, available phosphorus and available potassium in soil irrigated by mixed water and treated water increased obviously while the contents of N, P and K in plants changed little. So there is no close correlation between the nutrients in plants and those in soil, which indicates that nutrients in mixed water and treated water are not efficiently used by plants. The study of nutrient content in different soil layers demonstrates that after a long time of irrigation, main nutrients are apt to move downward except organic matter, and there are no significant differences in the three soil layers.