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1、15页Climateplaysaveryimportantroleinthegenesisofasoil.Ontheglobalscale,thereisanobviouscorrelationbetweenmajorsoiltypesandtheKoppenclimaticclassificationsystemsmajorclimatetypes.Atregionalandlocalscales,climatebecomeslessimportantinsoilformation.Instead,Pedogenes
2、isismoreinfluencedbyfactorslikeparentmaterial,topography,vegetation,andtime.Thetwomostimportantclimaticvariablesinfluencingsoilformationaretemperaturearidmoisture.Temperaturehasdirectinfluenceontheweatheringofbedrocktoproducemineralparticles.Ratesofbedrockweathe
3、ringgenerallyincreasewithhighertemperatures.Temperaturealsoinfluencestheactivityofsoilmicroorganisms,thefrequencyandmagnitudeofsoilchemicalreactions,andtherateofplantgrowth,moisturelevelsinmostsoilsareprimarilycontrolledbytheadditionofwaterviaprecipitationminust
4、helossesduetoevapotranspiration.Ifadditionsofwaterfromprecipitationsurpasslossesfromevapotranspiration,moisturelevelsinasoiltendtobehigh.Ifthewaterlossduetoevapotranspirationexceedsinputsfromprecipitation,moisturelevelsinasoiltendtobelow.Highmoistureavailability
5、inasoilpromotestheweathering,ofbedrockandsediments,chemicalreactions,andplantgrowth.TheavailabilityofmoisturealsohasaninfluenceonsoilpHandthedecompositionoforganicmatter.气候在土壤形成过程中扮演了重要角色。从全球尺度来看,主要的土壤分类和科彭气候分类法确定的主要的气候类型有明星的联系。在区域和地方性的范围内,气候显得不是那么重要。取而代之的是母质,地形
6、,植被和时间。温度和湿度是影响土壤形成的两个重要的变量。温度直接影响基岩风化产生矿物颗粒。温度越高,基岩转化为矿物颗粒的比例越大。温度同样影响土壤微生物的活跃度,土壤化学反应的频率和数量,植物生长的比例。大多数的土壤湿度是由降水减去蒸发作用控制的。如果降水超过蒸发作用消耗的水,土壤湿度就会很高。如果降水少于蒸发作用,土壤的湿度就会变低。土壤内大量的可用的水气会提升母岩温度和沉积,化学反应,还有植物生长。微生物也会影响土壤的PH和有机物的分解。Livingorganismshavearoleinanumberofproc
7、essesinvolvedinpedogenesisincludingorganicmatteraccumulation,profilemixing,andbiogeochemicalnutrientcycling.Underequilibriumconditions,vegetationandsoilarecloselylinkedwitheachotherthroughnutrientcycling.Thecyclingofnitrogenandcarboninsoilsisalmostcompletelycont
8、rolledbythepresenceofanimalsandplants.Throughlitterfallandtheprocessofdecomposition,organismsaddhumusandnutrientstothesoilwhichinfluencessoilstructureandfertility.Sur