以陕西省为例,运用1989-2008年全省耕地、林地、草地、建设用地的面积数据和全省煤炭、石油、天然气消耗数据以及2006年11个地级市耕地、林地、草地和建设用地面积数据,采用回归分析、IDW插值和Hopfield神经网络对其进行模拟,分析不同土地利用方式的碳排放效益,得出以下主要结论:(1)1989-2008年,全省的碳排放总量大体呈增加的趋势,年均增加178.869万t。(2)建设用地和耕地是主要碳源,林地和草地是主要碳汇。(3)2006年的断面数据表明,陕西省碳排放总量存在明显的区域差异。在3大区域中,关中地区碳排放最大,陕北地区次之,陕南地区最小;在地级市中,渭南市的碳排放量最高,杨陵区的碳排放量最低。(4)土地利用结构与碳排放量存在一定的相互关系。在林地比例不变的情况下,土地利用结构中建设用地和耕地的比例越大,则碳排放量越大。在以上研究结果的基础上,提出土地利用变化中低碳减排的相关建议。
Taking Shaanxi province for example,based on the statistic area data of cultivated field,woodland,grassland and construction land,data of consumption of coal,oil and natural gas from 1989 to 2008 and the statistic data of different land use patterns in Shaanxi province in 2006,the paper analyzed the carbon emission of land use patterns by regression analysis,IDW-interpolation and Hopfield neural network.The results were as follows:(1) the total carbon emission was increasing at average speed of 178.869×104 t/a in Shaanxi province from 1989 to 2008.(2) the main carbon sources were the construction land and cultivated field.The two main carbon sinks were woodland and cultivated field.(3) the amount of carbon emissions were different among regions in 2006: Guanzhong was the most one.Northern Shaanxi came next.The smallest one was Southern Shaanxi.Among cities of Shaanxi,Weinan was the highest one.Yangling was the lowest.(4) there was certain relationship between land use structure and carbon emissions.Land use patterns had a certain influence upon the carbon emission,and there are some mutual relations coexisted between them.When the proportion of woodland is constant,the more proportion of cultivated field and construction land accounted,the more quantities would be carbon emissions.The more proportion of woodland accounted,the more carbon emissions would be decrease.Some suggestions about low-carbon were put forward in order to reduce carbon emission.