Study On Soil Enzyme And Oxidized Organic Carbon In Karst Regions Of Huajiang Canyon

This research take the karst special zone as an object in Huajiang, study systematically the grain composition of soil, the aggregate performance, the elastic condition, the conventional nutrient content, the active organic carbon and the activity of soil enzyme through investigate in the outdoors, gathering soil sample and analyzes in the laboratory. The paper had determined initially the target of soil quality evaluation and its percentage, carry on the soil quality evaluation using the method of principal components analysis and compared the soil quality among various Chinese prickly ashes forest and the tree forest, the wild, the cultivated land, obtains the difference under various land utilization ways, provides the theory basis for the karst area soil quality improvement.(1) The soil oxidized organic carbon change remarkably in the different land utilization way. The content of oxidize the organic carbon of 1/3 mol·L^-1, 1/6 mol·L^-1 under the different land utilization way is tree forest > Various years Chinese prickly ash forest > Open land > Plants crops, 1/30 moL.L^-1 oxidize organic carbon is the Chinese prickly ash forest of 10 years old > Tree forest> Other year Chinese prickly ash forest > Open land >Farming; the content of oxidized organic carbon content in two types of fertilizer is mineral fertilizer > mineral fertilizer + organic fertilizer.(2) The change of oil enzyme activity under the different land utilization ways is obvious (except outside amylase, catalase activeness). Sucrase, amylase, proteinase activeness in Chinese prickly ash forest of 7 year, 10 year, 13 year, 14 years old is higher, next is tree forest, 2 years old fresh Chinese prickly ash forest activeness is lower, the activeness of sucrase, the acid phosphatase, the polyphenol oxidase, rease in the open land is lowest. The activeness of sucrase, the amylase, the proteinase, catalase in 2 years fresh Chinese prickly ash forest are lowest. The enzyme activity is lowest under other land utilization ways in farming. The most enzyme is situated between the open land and the cultivated land in the Chinese prickly ash forest; the change rease active, the polyphenol oxidase active is duplicate mineral fertilizer > mineral fertilizer + organic fertilizer, other soil enzyme activities are just opposite; the soil enzyme activity changed remarkable in different aggregates. The sucrase, amylase, rease, proteinase, phosphatase activity in different aggregate is 0.25mm>2-1mm> 5mm.(3) There are remarkable or the extremely remarkable pure correlational dependence among three kinds of oxidize the organic carbon, the organic matter, the entire nitrogen, the oxidize nitrogen and the soil enzyme activity(besides catalase); the 1/6th, 1/30 mol.L^-1 oxidize organic carbon and the fast-acting phosphorus have remarkable pure correlational dependence; there are pure remarkable correlational dependence between catalase activeness and the element of P or K, the polyphenol oxidase, sucrase activeness and the content of total P, the fast-acting P in soil existent remarkable and the extremely remarkable correlational dependence, the polyphenol oxidase, the phosphatase, 1/30 mol.L^-1 may oxidize in the organic carbon and the content of the total P in soil have the negative correlational dependence.(4)The soil quality sequence is 14 years Chinese prickly ash forest> Tree forest > 7th, 10, 13 years Chinese prickly ash forest> Plants crops > Open land > 5 years Chinese prickly ash forest > 2 years Chinese prickly ash forest.