污泥混配土中氮磷转化研究

Law for Nitrogen and Phosphorus Changing in Mixed Soil

污泥通过好氧堆肥反应腐熟,除去其中有害物质及降低重金属含量后达到农用标准,然后在温室大棚内进行种植实验,将堆肥按不同混配方式施入土壤中。研究污泥混配土中氮磷的变化表明:混配土中的总氮在种植过程中被作物吸收和自身流失,有一定程度降低;氨态氮经过转化和作物吸收,降低很快。混配土中总磷的含量在种植过程中基本不变,作物生长只需少部分磷,在温室中种植避免了磷的流失;速效磷的变化较为复杂,种植一段时间后,速效磷呈现上升趋势。

Sludge was used as raw material for fast composting to remove hazardous substance and reduce the content of heavy metals to satisfy the standard of agricultural use. The composted sludge was used in the soil of greenhouse as fertilizer to study the changing of nitrogen and phosphorus content. Results showed that total nitrogen in the mixed soil decreased to certain extent in the process of planting due to the plant absorption and self loss while ammonia nitrogen was depressed rapidly by absorption and transformation. Content of total phosphorus in the mixed soil was unchanging since crops need little phosphorus in growing and phosphorus loss was avoided in the greenhouse. Changing of rapidly available phosphorus was complicated, and the contents were ascended after some time of growing.