在GIS的支持下,利用地面气象数据和MODIS数据,考虑到最大光利用率在不同植被类型中的差异,构建了一个区域陆地植被NPP估算模型,并以2002年的内蒙古植被为例,研究了植被净初级生产力及其时空分布。结果表明:(1)该模型在数据获取了上比较容易,仅利用地面气象数据和遥感数据就可以对陆地植被NPP进行估算,使其实际的可操作性得到加强。(2)通过与NPP的实测资料及其他模型的对比研究表明:该模型对区域陆地值被NPP的模拟效果较好,与Chikugo模型相比,它更能反应森林NPP的实际情况。(3)2002年内蒙古植被净初级生产力为390.8MtC/a,总体分布趋势是由东北向西南递减,其季节变化也非常明显,在6月中旬至9月中旬的3个月时间里,NPP占了全年的72.7%,而1—2月份植物基本停止生长,净初级生产力极低,每月仅为3.59MtC。

According to recent studies that there are important differences in maximum light utiliazion efficiency(εmax)\namong vegetation types,an estimation model of net primary productivity (NPP),based on geographic information system\n(GIS)and remote sensing (RS)technology,is presented.This model has two significant characteristics;(1)NPPcan be\nestimated just using ground meteorological data and remote sensing data.It is relatively easier to acquire data and its ap-\nplication can be enhanced.(2)Afterthe validationwith observed data and the comparisonwith otherNPPmodels,the re-\nsults showed that the predictedNPPwas consistentwith observed values,and it can more actually reflect the forestNPP\nthan Chikugo model.In order to validate theNPPmodel,a case study in InnerMongolia,China,was carried out.The re-\nsults showed that the total annualNPPin InnerMongolia in 2002 was 390.8 Mt C.The spatial changes ofNPPwere re-\nmarkable,and it decreased from northeast toward southwest .Moreover,seasonal variations ofNPPwere also large.Itwas\nabout 72.7% of the total annualNPPin the three month of June,July and August,and theNPPvalues was very low\n(3.59 Mt C per month) in January and February.