再生水灌溉对旅游区土壤理化性质时空变化影响特征分析

Study on spatial-temporal variation characteristics of soil physicochemical properties affected by irrigation with reclaimed water

通过对桂林园林植物园内的绿地实地调查，对再生水灌溉对土壤理化性质影响的时空变化特征进行研究。结果表明：各土层土壤有机质、总氮的含量随时间的变化并不十分明显；0-30cm土层土壤速效磷含量随时间的变化较小，30～60cm土层土壤速效磷含量变化相对较大；0-15cm土层土壤全盐的变化较大，15cm以下土层土壤盐分的变化相对较小。0-60cm各土层中，再生水灌溉时的土壤有机质、总氮、全磷、全盐含量均高于清水灌溉条件下的含量。再生水灌溉对土壤有机质、全氮、全磷、速效磷、速效钾、全盐、K＋、Na＋、Ca2＋、Cl-含量有显著或极显著的影响，对容重、速效氮、pH、Mg2＋、NＯ3--N、NH4＋-N等6项土壤理化指标则无显著影响。与清水灌溉相比，再生水可以明显地提高土壤肥力，为植物生长提供充足的氮、磷、钾等营养元素和有机质，但也会引起土壤全盐含量的升高，应采取相应措施避免盐害发生。

Through the site investigation in Guilin Botanical Garden, the research of lawn ecosystem irrigated with reclaimed water has been carried out, and the spatial-temporal variation of soil physicochemical properties due to the reclaimed water irrigation has been studied. The result indicated as following： Temporally, there＇s no obvious variation of the content of organic matter and total nitrogen in every soil layer; in the 0-30 cm soil layer, there＇s relatively small change in the content of soil available phosphorus, while that change was relatively big in 30 -60 cm soil layer; in 0-15cm soil layer, the change of total salt content was comparatively small and that change was relatively big in 15-60 cm soil layer. Spatially, in each soil layer the content of organic matter, total nitrogen, total phosphorus, and total salt in the soil irrigated with reclaimed water were all higher than that in the soil irrigated with clear water. The irrigation with reclaimed water did have remarkable or extremely remarkable influences on the content of organic matter, total nitrogen, total phosphorus, rapid available phosphorus, rapid available potassium, total salt, K＋, Na＋, Ca2＋ and Cl-, however, there＇s no remarkable influences on the bulk density, rapid available nitrogen, pH, Mg2＋, NO3--N and NH4＋-N. Compare with fresh water irrigation, reclaimed water containing nitrogen, phosphorus, potassium and other nutrients and organic matter, which will promote plant growth and improve soil fertility, at the same time, it will enhance the total salt content of soil, so the corresponding measures should be taken to avoid salt harm.