Dynamic And Pattern Of Hydrologic Function Of Litter In Natural Manchurian Ash Forest

Based on geo-statistics theory,the average amount of the present remaining litters,the litter decay rate and the static water-holding capacity of Manchurian ash natural forest were investigated and analyzed during the whole year.And combined the influence law of different thickness,decomposition degree and previous water content to soil evaporation and infiltration,the hydrological function was studied systematically and semantically.The purpose was to prove up the relation ship between the temporal and spatial distribution characteristics of Manchurian ash natural forest litter layer to water source self-control and conservation function.The total amount of the present remaining litters was approximately 25.05t/hm~2,and almost didn't change with the time.The whole year total rate of decomposition may reach 53.27%,the regular periodic rate of decay varied between 0～7.61%range of,and dynamic change with the season:in autumn,decomposition speed is low,average rate was 4.67%;in winter,which reduced to 0.35%;in spring,the rate increased gradually with the small increase scope,the average rate was 1.89%;Until to the summer,the decomposition speed rapidly increase,achieved the peak value,its average rate of dissociation is 6.45%.Litter static water-holding capacity was most greatly between 491.7%～545.2%,and the annual variation dynamic rule was similar with litter decay rate.The Manchurian ash natural forest litter layer had a unique spatial pattern,the variation is extremely remarkable especially in the small criterion.At the same time,edaphon's quantity,the litter decay rate and static water-holding capacity also presented the obvious small mottling distribution pattern in the space.Among them,the spatial distribution pattern of actinomycetes and the static water-holding capacity were similar with the litter decay rate, being the remarkable linear fitting degree,and R~2 was respectively 0.8524 and 0.9776.The correlations of Edaphon's quantity,the litter decay and the static water-holding capacity were closer.Namely that,the microorganism quantity are more,the decay rate will be bigger,and its static water-holding capacity will be stronger,and actinomycetes was the main strains influencing the rate and degree of litter decomposition.The influence of thickness of Manchurian ash natural forest litter layer to soil evaporation and infiltration was the most prominent,but the role of litter decay degree as well as preliminary moisture content was relatively small.When the litter thickness was more than 3cm,the inhibition of evaporation was remarkable;compare to the control,the increase scope of accumulations infiltration quantity within 60 minutes was: 402.33%(3cm)＜416.28%(4cm)＜447.29%(5cm)＜504.65%(6cm),namely that:with litter thickness increasing,the inhibitory action to soil evaporation will be more obvious,the promoting of soil infiltration will be stronger.May believe that,when the total amount of the present remaining litters was stationary,more thicker of the litter lay and more bigger of the decomposition degree,its static water-holding capacity and soil infiltration ability will be stronger,and more favor the suppression soil evaporation,reduce the soil moisture loss,may well display the function of water source self-control and conservation.