不同季节生态沟净化养殖废水能力对比研究

Abilities of Ecological Ditch to Purify Livestock Wastewater in Different Seasons

研究了不同季节生态沟对低浓度养殖污水净化效果,结果表明:在夏秋季,生态沟对COD和TN的削减率均达到86%以上,对于TP的削减率高达98%以上。夏季生态沟对养分的削减能力要优于其他处理,秋季其次,然后是春季,最差是冬季。即使水生植物进行了刈割,生态沟依然能发挥一定的净化效果。随着生态沟的运行时间积累,底泥中养分含量快速增加。初始阶段增加最快,但随着生态沟的延长,3种污染物的浓度急剧下降,到生态沟末端,底泥的养分含量变化已经不显著。生态沟中初始段的水生植物的生物量最高,随着生态沟的延长生物量显著下降,末端点最低,水生植物吸收N素产生的削减占生态沟总削减量的28%,吸收P素占总削减量的8.7%。

The aim of this paper is to study the effects of purification of low concentration farming wastewater in ecological ditch in different seasons. The results showed that：the reduction rates of COD and TN were more than 86%, and that of TN was more than 98% in summer and autumn. The ecological ditch was better than other treatments for nutrient reduction in summer, followed by autumn, then spring, winter was the worst. Even the aquatic plants were mowed, the ecological ditch still could play a certain purification effect. With the accumulation of ecological ditch running time,the nutrient contents in the sediment increased. Increase was the fastest in initial stage of ecological ditch, and but the concentration of three pollutants decreased sharply to the end of the ecological ditch with the extension of the ecological ditch, and the change in nutrient contents of sediment were insignificant. The biomass of the aquatic plants in the initial section of the ecological ditch was the highest, then decreased significantly along with the extension of the ecological ditch, and was the lowest at the end point. The amouts of N and P absorbed by aquatic plants accounted for 28% and 8.7% of the total reduction amonuts in the ecological ditch.