es:resourcedecreasedslowly(fromHanDynastyto1933,annualaveragedecreaseof 984hm 2),resourcedecreasedsharply(1933~1979,annualaveragedecreaseof27800hm 2) andresourcedecreasedslowly(1979-1987);from1978to1998,theresourcewasrestored steadily,annualaverageincrease20300hm 2.3)Thespatialchangesaremainlyrepresentedin theprocessofdeforestationtakingplacefromcoastalplainandmesatoinlandhillandbasin, andfinallytomountainousareainthemiddleoftheisland.4)Themainfactorswhichaffect thetropicalforestarenotthesameindifferentphases.FromHanDynastyto1933,itisjust duetoaboriginalcultivation;from1933to1950,itisduetoplunderingcuttinganddestroy2 ing;andinthelast50years,theultimatecauseisduetooverfastincreasingofpopulationand changesinpolicyandeconomysystem. Keywords:HainanIsland;tropicalforestchange;hange 712 地理研究 20卷
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