36545.塔克拉瑪干沙漠北緣荒漠河岸植物群落對水分和氮素輸入的響應

1、中國科學院新疆生態(tài)與地理研究所博士學位論文塔克拉瑪干沙漠北緣荒漠河岸植物群落對水分和氮素輸入的響應姓名：李寧申請學位級別：博士專業(yè)：生態(tài)學指導教師：田長彥馮固20080601摘要IIlTheresponseoftheplantcommunitytothewaterandnitrogeninputtinginthedesertriverbankatthenorthedgeofTaklimakanDesertLINing(ecology)D

2、irectedbyprofTIANChangyanandFENGGuAbstractInordertounderstandtheinfluencestOthedesertecosyStemplantcommunitycharacteristicsandthemechanismofthedesertecosystemstabilityofthesaltwaterandnitrogeninputtingwhichcomefromtheinc

3、reasingsubsidence，theexperimentswerecarriedoutintheriverbankatthenorthedgeofTaklimakanDesertsfrom2004to2005Theinfluencesofdifferentlevelwaterandnitrogeninputtingwereresearchedthoroughly，includingthesoilcharacteristics，th

4、ecommunitycharacteristicsofovergroundvegetation，soilseedbankandtheinterrelationshipbetweentheseedbankandtheovergroundvegetation，whichcouldprovidethetheorybasisforthecontributionsofmoisturecontentandnitrogenandthecorrelat

5、ionmechanismoftheminthecourseofvegetationrecoverywiththeriverTheresultsweresummedupasthefollowing：Theinputofwaterandnitrogenimprovedthesoilnutrientcontent，moisturecontent，reducedthepHsignificantlyTheinputofsaltwaterbroug

6、htthefluctuatedchangeofsurfacesoilsaltcontentandthesaltcontentincreaseofthewholesoilWaterandnitrogenaffectedtheplantcommunitydensityandthestructuralcompositionsignificantlyThedensityincreasedsignificantlyalongwiththeincr

7、easingofwaterinputting，butthesensitivitiesofdifferentspeciesrespondingtOthewaterandnitrogenweredifferentTheplantcommunitycoverageandNPPincreasedalongwittltheincreasingofwaterandnitrogeninputtingWaterandnitrogenchangethes