Study On Soil Biological Properties Of Green Manure-whert Rotation And Nitrogen Rate

Since the20th century, the Contradiction between population, food, resource andenvironment become more and more worsened. In the agricultural soils exist someoutstanding problems especially the last two decades, such as the reduced of the soilqualityand and pollution depend an lack of soil organic matter, excessive application ofchemical fertilizers and pesticides. The sustainable development of agriculture became moreand important for china. Green manure is a main organic fertilizer, it canImprove soilnutrients, improve soil structure, ensuring the food security. Green manure is one of importantplants which can fix carbon and reduce nitrogen, and have influence on organic matter,Available N supply and continuous cropping obstacle remediation in dryland of loess plateau,inculd reduce the pollution of chemical fertilizer. Over the years, Loess Plateau’ soil fertilitywas inadequate, also had a long time and a wide area traditional summer fallow period. In thispaper, field experiment were carried out to investigate the effect of leguminous green manurein summer fallow period on soil biological indicators properties and to reveal the mechanismof improving soil fertility,choosen the better green manure.1. After the five years, compared to the fallow treatment, green manure could improvedsoil invertase, urease, alkaline phosphatase, arylsulfatase and dehydrogenase activity. In mostcases, huai bean could activated soil enzyme activity, TEI can also proce it. Nitrogenousfertilizer application could inhibit soil invertase and arylsulfatase enzyme activity, but noimpact to alkaline phosphatase.TEI is higher in N0and N1nitrogenous fertilizerapplication.Green manure, nitrogenous fertilizer application and their interaction have a hugeimpact on soil enzyme. Correlation analysis showed that soil invertase, urease, alkalinephosphatase, and TEI can evaluate the soil fertility improvement effect of GM.2. Green manure could increase soil urease kinetic parameters Vmax, Vmax/Km and k,but no impact on Km. much nitrogenous fertilizer application may weeken urea hydrolysis.Green manure could increase soil alkaline phosphatase kinetic parameters Vmax, Km,Vmax/Km and k. nitrogenous fertilizer application has no much impact on it.this reflect thedifferent between these two enzymes. Kinetic parameters and soil organic matter, availablepotassium had a good positive correlation.Huai bean has a good effect on kinetic parameters. 3. Green manure could significantly increase the number of the total number ofmicroorganisms, bacteria, actinomycete and B/F. Pressure green manure to the soil has abetter effect. Green manure has a certain inhibitory effect on fungi except huai bean. MuchNitrogenous fertilizer application could inhibit the number of bacteria and actinomycete.Invertase, urease, alkaline phosphatase and bacteria, actinomycete had a good positivecorrelation.4. Green Manure can significantly increased microbial biomass carbon and nitrogen content,Pressure green manure to the soil has a better effect after2weeks, Huai bean has a goodeffect on microbial biomass. Much Nitrogenous fertilizer application could inhibit themicrobial biomass nitrogen but no effect on microbial biomass carbon. SMBC/SOC alsohave improvrd by it.