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SiteandmethodThesiteislocatedintheSuiIingDistrictofHeiIong-jiangProvincefromN47"26'toN48"o6',E127"37'toE128"28'.TheaveragesIopeis15".Themeanelevationis349m.ThemeanannuaItem-peratureis-o.4t.TheaccumuIatedtemperatureof31ooCis1986C-Theamountofprecipitationisfrom6ooto8oomm.Thefrost-freeseasonisabout13od.ThemainsoilisdarkbrownsoiI.The17plots(o.o4hm')fordifferentages,differ-entsitesweremeasured.OnesampletreewasseIectedineverypIot,ThefalIenstemanalysistreesweredividedwithonemeterortwometer…  相似文献   
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IntroductionThereareabout2,ooo,ooohm2Ofsoda-saline-alkaIisoilinSonglunpIaininHeiIongjiang(Shen1998).ltisdistributedmainlyinZhaodong,Zhaozhou,Zhaoyuan,Anda,Daqing,Duerbuteandothercountiesandcities.FormerIy,therewerenotreesonsoda-saline-alkaIisoil.CropscannotgrowonsuchsoiIs.PIantingtreesonthesesoilsmightimproveonitsquaIity(LingetaI1982).TostudypIantingonsoda-saline-aIkalisoiIhassignificanceforestablishingprotectivepIantationsystemofgrasslandandestabIishingperfectprotec-tivepIantations…  相似文献   
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