草原退化過程中植被的空間分異及生態(tài)適應性研究碩士論文

1、遼寧師范大學碩士學位論文草原退化過程中植被的空間分異及生態(tài)適應性研究姓名：霍光偉申請學位級別：碩士專業(yè)：植物學指導教師：呂建洲；烏云娜201206草原退化過程中植被的空間分異與生態(tài)適應性研究ThestudyofvegetationspatialdistributionandecologicaladaptabilityunderdifferentgazingintensitiesAbstractInthisstudy，theHulunbe

2、rStipakryloviitypicalSteppeintheeastofInnerMongoliawasusedasinvestigationobjectAccordingtothedifferentresearchwaysmultiscaleschemeandcombinedfieldsurveyandindoorexperimentwouldbeadoptedtodotheresearch111ecommunitycharact

3、eristics，spatialdistributionandecologicaladaptabilityoftherepresentweretestedandtheeffectofgrazingonthegrassproductionwasrevealed，moreover，theresponsemechanismofvegetationtoglobalchangewasanalyzedunderdifferentdegradatio

4、ndegreesThemainresultswereasfollows：(1)TwomajorcommunitiesandtwosubordinatesecondarycommunitiesweregeneratedaccordingtotheBraun—Blanquetcoverageclassification：AssAlliumtenuissimumArtemisiafrigidaAlliumtenuissimumArtemisi

5、afrigidaChenopodiumacuminatumHeteropappusaltaicusAssSetariaviridisEuphorbiahumifusa但)111ecommunitystructurewasdifferentinthethreecommunitiesunderdifferentgrazingintensitiesofSnpakr#o誠steppe111elightgrazingcommunitywasmai

6、nlycomposedwithleguminousGramineaeandCompositaeplantsandtherewere11branchplants；111emoderategrazingcommunityWasmainlycomposedwithLiliaceae，Gramineae趾dCompositaeplantsandtherewere9branchplants；111eheavygrazingcommunitywas

7、mainlycomposedwithgramineousplantsandtherewere9branchplants(3)燦1thecommunitiesweremainlycomposedwithperennial，xerophytesherbaceousplantsunderdifferentgrazingintensitiesofStipakryloviisteppeSeedpropagationplantshadtheadva

8、ntageinaridandsemiaridstepperegionThetussockformcharacteristicWasthemostbeneficialtothegrowthcompetitionofplantsnleXerophyteandmesoxerophytesplantsdecreasedwiththeincreaseofgrazingintensityMesophyteandStrongxerophytesbeg

9、antoappearandmesoxerophyteplantsdisappearedwithgrazingpressureincrease(4)Frommoderatetoheavygrazinggrazingcommunity，speciesrichnessWasdifferentwhichwasinlinewiththeintermediatedisturbancehypothesis”Thecommunitybiomassdec

10、reasedwithgrazingintensitydecreases；thediurnalphotosyntheticchangesofdominantspeciesare”doublepeak”curveinthethreecommunitiesunderdifferentgraz她intensitiesofSnpakr#ovasteppeThenutritiondistributionofcommunitydominantplan