biodiversityfeaturesofthemainsteppecommunitiesininnermongoliaandtheirrelationstoclimateandgrazing

？onehundredsteppecommunitieswereinvestigatedonclimategradientsinthecentralinnermongolia.themaincommunitiesweredominantedbystipagobica,s.breviflora,s.krylovii,s.grandis,s.baicalensis,aneurolepidiumchinense.filifoliumsibiruutnandfestucadahurica,etc..theirspeciesdiversityfeatureswereanalyzedinrelationtoclimatefactorsandgrazingintensities.theresultsshowedthatspeciesrichness(s)insteppecommunitieswaspositivelycorrelatedwithprecipitation(s=—5.1？e0.00627p;r=0.85,p=0.001),butnegativelywithtemperature(t)(s=50.9？e-0.225t;r=0.92,p<0.001).thespeciesrichnessdecreasedasclimatearidity(a)increased(s=—41.81+48.03e1/a,p<0.001).thecommunitiediversityhadsimilartendenceofchangewithspeciesrichnessalongclimategradient.thehighestdiversityalwaysappearedatmoderatelevelofgrazingintensityforacertaincommuity.whichwasduetothepreventionofexclusivecompetitionofspeciesbymoderategrazing.anintegratedschematicmodelontherelationshipofcommunitydiversitywithclimatearidityandstockingratewasproposed.