光照强度和温度对三峡水库消落区典型土壤磷释放的影响

Effects of Light and Temperature on Phosphorus Release in Typical Soil of Drawdown Area of Three Gorges Reservoir

[目的]考察3种土壤的释磷量在不同光照和温度下的变化规律。[方法]将采自重庆市涪陵区消落带的沉积物、水稻土、紫色土移至实验室内进行磷释放模拟试验。[结果]在不同模拟光照强度下,上覆水总体上偏碱性,pH和总磷均随光照强度的升高而增加。在不同温度下,总体上水体偏碱性,pH随温度的升高而增加,总磷随温度的升高而减小。[结论]光照强度促进土壤微生物把土壤中的有机态磷转化为无机态磷,从而促进内源磷的释放。温度对土壤磷释放的影响主要表现为受温度影响而生长的微生物吸收土壤释放的磷,阻挡其进入上覆水中。同一光照强度和温度条件下的土壤释磷量顺序为紫色土>水稻土>沉积物。

[ Objective ] The research aimed to study the change regularity of phosphorus release of the three kinds of the soils under different light and temperature. [ Method ] The sediments, paddy soil and purple soil from the drawdown area of Fuling District in Chongqing were used for laboratory experiments on phosphorus release. [ Result ] pH and TIP increased with the increase of light intensity, and the water was in al- kali after equilibrium, pH increased with the increase of the temperature, and the water was in alkali after equilibrium, but TP decreased with the increase of the temperature. [ Conclusion ] Light promoted microbiology to transmit OP to IP from soil, thus accelerated the release of phos- phorus from soil into the overlying water. Microbiology controlled by light took up phosphorus released from sediments, and thus prohibited phosphorus into the overlying water. The order of total phosphorus under the same temperature and light intensity was that the sediments 〈 the paddy soil 〈 purple soil.