| Xiaolong Mountain Nature Reserve is the most primitive forest ecosystems inour warm temperate-subtropical transition region to save, is a nature reserve of forestecosystem types, is the transition zone of humid subtropical climate zone and thewarm temperate watershed for the north-south climate. The natural environment in theprotection region is original, unique. Species ancient rare, biodiversity typical rich.This article select the Xiaolong mountain four representative forest vegetationunderstory soil sampling and analysis of soil environmental characteristics of differentvegetation types, determination of the number of soil physical and chemical propertiesof various vegetation types and soil microorganisms, and a detailed study ofcorrelation of each soil microbes and soil physical and chemical properties. Theresults are as follows:（1） soil physical and chemical propertiesPhysical properties: four different vegetation soil bulk density range from0.88to1.14g/cm3; porosity in the range of53.17to64.62%; field capacity in the range of22.73to33.46%Chemical properties: four different vegetation soil pH range from5.46to6.75;soil organic matter in the range of0.99to9.51%; available nitrogen in range of16.19to196.3mg/kg; available phosphorus in the range of1.2589.0mg/kg; availablepotassium in the range of7.26220.3mg/kgGood nutrition can be judged according to soil nutrient level standards of soil,the local nutrient grade level were higher.（2） soil microorganism numbersSoil microbial flora of the total number for the three categories of broad-leavedmixed forest is806.188×105cfu·g-1dry soil; Japanese larch forest2311.681×105cfu·g-1dry soil; Chinese pine forest2544.222×105cfu·g-1dry soil; sharp tooth oakforest7295.452×105cfu·g-1dry soil. Each vegetation type of soil are the highestnumber of bacteria, actinomycetes, followed by fungal least; vertical profiles showeda significant vertical distribution characteristics.The total number of microbial functional flora is the Chinese pine forest39.36×105cfu·g-1dry soil; Japanese larch forest32.59×105cfu·g-1dry soil; broad-leaved mixed forest43.22×105cfu·g-1dry soil; sharp tooth oak forest68.2×105cfu·g-1dry soil. Each vegetation type, soil phosphorus solubilizing bacteria count up,and the second is aerobic nitrogen-fixing bacteria,the third is the solution ofpotassium silicate bacteria, the minimum number is aerobic cellulolytic bacteria.Various types of functional bacteria in the vertical profiles of various vegetation alsoshowed significant vertical distribution characteristics.（3）the correlation of the soil physical and chemical properties and the quantityof microorganismsThe study found the number of bacteria in the soil and water content showed asignificant positive correlation with organic matter content has displayed significantpositive correlation prove the growth of bacteria need plenty of water and nutrients;soil fungi quantity and soil pH value showed a significant negative correlation,indicating a fungus like growth in the acidic environment. Most kinds of nutrients likesoil water content, organic matter content and available nitrogen, phosphorus,potassium content showed a positive correlation between the actinomycete numbers.Aerobic nitrogen-fixing bacteria and soil moisture showed a positive correlation,aerobic nitrogen-fixing bacteria on soil pH reaction is more sensitive, of aerobicdiazotrophs and soil organic matter content in various soil depth showed a positivecorrelation and with the available nitrogen in the soil showed a negative correlation,prove that in carbohydrate-rich environment and lack compound nitrogen descriptionnitrogenase classes bacteria need to be conducive to fully play its nitrogen fixation.With phosphorus and potassium content in the middle soil depth showed a positivecorrelation with the Aerobic nitrogen-fixing bacteria can promote that nitrogen-fixingbacteria combined application of phosphorus, potassium and other trace elements canpromote the activity of the nitrogen-fixing.Phosphorus solubilizing bacteria and moisture content showed a positivecorrelation and with the pH value showed a positive correlation,phosphorus-solubilizing bacteria in the middle soil depth growth pH environment isalkaline, and organic matter content in each soil depth showed a positive correlation,indicating the the dissolved phosphorus growth of bacteria and to play the role ofdissolved phosphorus also need adequate nutrient supply.With available nitrogen and available potassium in middle soil depth showed a positive correlation and showed anegative correlation with available phosphorus content in the middle and deep soildepth,prove dissolved phosphorus bacteria need rich in carbohydrates, but they lackof compounds of phosphorus in the environment and can help give full play to itsphosphate solubilizing effect.Solution of potassium silicate bacteria and soil water content showed a negativecorrelation and with the pH value of the correlation is not obvious, silicate bacteria donot ask for much nutritional conditions, strong adaptability to environmentalconditions.Show some positive correlation with the organic matter content, thesolution of potassium silicate bacteria growth reconciliation potassium role to playalso requires a certain amount of nutrient supply. Available potassium content in themiddle and deep soil depth showed negative correlation with soil available potassiumprove that to play the role of the potassium content of the soil if it is too high it willeasy inhibiting solution of potassium silicate bacteria breeding reconciliationpotassium.Aerobic cellulose-decomposing bacteria in soil with water content in the topsoiland middle showed a negative correlation with soil pH in the surface soil showed apositive correlation, showing a positive correlation with the organic matter content,indicating to play the role of aerobic cellulose-decomposing bacteria growth anddecomposition of cellulose requires nutrient supply. Aerobic cellulose decomposingbacteria and available nutrients correlation is not very significant. |
PDF Full Text Request