%0 Journal Article %T 从生态学论“三北”防护林在宁夏的规划原则 %A 胡式之 %J 植物生态学报 植物生态学报 %P 156-163 %D 1984 %X ?NingxiaHuiAutonomousRegionissituatedin30;14′–30;14′and30;33′–30;39′.Thoughitsarea.Isonly67000km2,ithasmanyvariousecosystemcategories.Thevegetationisthecoreoftheecosystem,soitisveryimportanttoresearch.ThevegetationinNingxiaisthecombinationofmanyvariousvegetationtypeswhichhavecertainegularityofecogeographicaldistribution.ThezonalvegetationtypesinNingxiaarcthesemi-desert,thesteppeandthemeadow-steppefromnorthtosouth.AndtherearethespectrumsoftheverticalbeltsofthevegetationinHelanmountainandLupanmountain.Therearealsomanyintrazonalvegetationtypes—thesaline-meadow,thegrass-swamp,thesaltvegetation,etc.Everyvegetationtypeexistsmanyvariousplantcommunities.Andeachvegetationtypeorplantcommunitycanreflectthecomprehensiveecologicalfactors.Accordingtotheregularity,wemayputforwardaprincipleofplanofthe"Sanbei’(northeast,northandnorthwestChina)shelter-forestinNingxia:l.ItissuitabletoestablishthescrubbeltsinNingxia.Inthesemi-desert,thesteppe,themeadow-steppeandthegrass-tuft,thesoilerosionontheslopesmaybecontroledbythescrubbeltsfollowingcontour-lineandthewind-sand-harmontheplateauplainmaybepreventedbythescrubnetworks;2.Toplanttheshrubs,thesemi-shrubsandthetherophytesissuitableforfixingthesanddrift;3.Itisn’tdifficulttoplanttheshelter-forestintheirrigationfarmland.Butitisveryimportanttochoosethetreespeciesadaptingvarioussoil;4.Alloftheforestandthescrubinthemountainsmustbeclosedandtended.Themixed-forestmaybeexpandedonthemeadowslope. %U http://www.plant-ecology.com/CN/abstract/abstract8580.shtml