中文摘要：

基于2000-2012年的遥感数据和气象台站实测数据,利用光能利用模型对陕北地区植被净第一性生产力进行了测评,从而计算得到植被固碳价值量,进而估算出陕北各个县区CO2治理成本,并采用Theil-Sen趋势分析其变化特征。结果表明：（1）2000-2012年陕北大气中超出350×10^-6的CO2、生态固碳与需要治理的CO2的多年月均值分别为12.58、0.76和11.81 t·hm^-2,月变化率分别为0.066 0、0.002 7和0.063 2 t·hm^-2·mon^-1。（2）在CO2治理单位面积的平均成本核算中,森林、灌丛与草丛属于生态型植被,产生一定的经济效益,其他植被类型均属消耗型,其中投资成本由大到小依次为荒漠植被〉草原〉栽培植被〉草甸。（3）空间上,由于不同地表覆盖固碳的差异性,陕北单位面积CO2治理平均成本由南向北逐渐增大。陕北南部属于生态型,各县区产生一定的经济效益,陕北中北部地区属消耗型,分县区单位面积CO2治理平均成本居高不下。（4）2000、2006和2012年陕北CO2治理合计成本分别为3.40×10^8、9.42×10^8与18.16×10^8元·a^-1。CO2治理合计成本变化率由东向西、由东南向西北逐渐递增,陕北南部县区CO2治理合计成本变化相对较慢,而陕北中北部的CO2治理成本在极显著升高。

英文摘要：

The photosynthesis of green plants can absorb carbon dioxide and release oxygen, which helps keep the atmosphere balance of CO2 and O2. Measuring the value of carbon fixation and oxygen release is very important for understanding the ecological sYstem as well as its change. The cost of atmospheric CO2 treatment and their dynamic changes were analyzed based on remote sensing and meteorological data in northern Shaanxi. Light energy utilization model was used to estimate Net Primary Productivity （NPP） with MODIS/NDVI data, and then NPP was converted to the amount of CO2 fixation through photosynthesis equations. Finally, the values of CO2 fixation and the least cost of atmospheric CO2 treatment in northern Shaanxi ecosystem were Computed by using forestation cost method. Results show as follows： （ 1 ） The cost of CO2 treatment from high to low was： desert 〉 steppe 〉 cultivated vegetation 〉 meadow 〉 forest. Therein, forest, bushwood and grass belonged to ecological vegetation which could produce a certain economic benefit; while other vegetation belonged to consumptive vegetation. （2） Due to the otherness of different land cover, the mean cost of CO2 treatment increased gradually from south to north part of northern Shaanxi, which is because that the vegetation in south part of northern Shaanxi belongs to the ecological type, while vegetation in north and central part of northern Shaanxi belongs to the consumptive type. （3） The change rate of total cost increased from east to west and from southeast to north-west. And the growth rate of southern part of northern Shaanxi is slower than that in north and central part of northern Shaanxi. The cost of atmospheric CO2 treatment presents a significant difference between south and north region in northern Shaanxi, which is mainly due to the otherness of different land cover. South part of northern Shaanxi which belongs to semi-humid region has relatively high vegetation, therefore, the vegetation can not only fix more CO2 but also can produce a