The Ecological Effects Of Environmental Hormone Diosgenin And Its Degradation Behavior In Soil

In this research, the effects of diosgenin to the soil microbe and enzyme activity by simulation in laboratory were studied, the degradation dynamics of diosgenin in different soil environmental conditions was also discussed.The main results are summarized as follows:The effects of diosgenin on the population of soil microbe indicated that:to the fungi and nitrifiers, the inhibition numbers of fungi and nitrifiers were increased with the increased concentration of diosgenin, then gradually lose the inhibition, finally was similar with the CK; to bacteria,it was stimulated slightly by diosgeninon; to ammonifiers and actinomycetes, low concentration of diosgenin stimulated the growth of ammonifiers and actinomycetes,with the concentration increased the growth of ammonifiers and actinomycetes was inhibited, this situation was just displayed at earlier period, at later period the growth of ammonifiers and actinomycetes become normal.The results of the dynamic study of soil enzyme, catalase, sucrase, and urease showed that: effects of the catalase in soil displayed slight activation in the whole experiment period; the inhibiting effects of diosgenin on sucrase was increased with the increasing concentration of diosgenin, the sucrase activity in low concentration treatment was inhibited until 14^th days, the higher concentration treatment was inhibited until 30^th days, then gradually lose the inhibition. The effect of diosgenin on urease activites in soil displayed stimulated at earlier period, as time goes by, this stimulation gradually get down and went similarly with (CK).The degradation experiments of diosgenin in different environmental conditions were tested in the laboratory. The results indicated that the degradation rule of diosgenin accorded with decaying exponential, which means that there was a inverse linear correlation between the logarithm of diosgenin concentration and the time. At the comfortable condition, the half-life of diosgenin was 12.86days, The degradation of diosgenin with different nitrification/urease inhibitors in soil exhibited different results, for DCD the effect was negligible, for TU there was a slightly inhibition, for HQ, the inhibition of degradation thaws increased with the increasing concentration of HQ.with high concentration of HQ in soil, the half-life belated 60.01 days.