喀斯特地区植被净第一性生产力遥感动态监测及评价--以贵州省中部地区为例  

Estimation of Vegetation Net Primary Productivity of a Typical Karst Area in Central Guizhou

作　　者：王玉娟[1] 杨胜天[1] 吕涛 刘瑞禄 

机构地区：[1]北京师范大学地理学与遥感科学学院,遥感科学国家重点实验室,北京100875 [2]贵州省水利厅,贵州550002

出　　处：《资源科学》2008年第9期1421-1430,共10页Resources Science

基　　金：国家重点基础研究发展计划(973)“酸沉降对森林植被和农作物的影响及其评价方法研究”(编号:2005CB422200);国家自然科学基金项目“岸边缓冲带对非点源污染控制效应的遥感解析(编号:40671123)”;“高等学校学科创新引智计划资助”(Supported by the 111 Project)(NOB06004);长江学者与创新团队发展计划协助

摘　　要：在光能利用率原理基础上,对CASA模型中的水分胁迫因子进行改进,将土壤水分含量作为一个直接变量引入模型,建立起针对于黔中部喀斯特地区的植被NPP估算模型;并与土壤水分层均衡模型进行有效耦合,得到模型所需的土壤水分含量,在此基础上,依托遥感和GIS手段,将模型扩展到区域尺度上,模拟出黔中部喀斯特地区2005年10月～2006年5月月尺度上的植被净第一性生产力动态变化特征,并以实测值进行了验证。结果表明:①该模型在数据获取上比较容易,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;将土壤水分含量作为一个直接变量引入模型,从而可以从模型本身,对土壤水分与植被NPP的直接响应关系进行深入探讨,得到生态脆弱区植被生长的土壤水分敏感点,为区域植被建设和生态恢复提供一定的依据;②不同植被类型下植被NPP变化特征有着重要的差异。林地的植被NPP最高,平均值为19.89gC/m2,其次为灌丛,为19.01gC/m2,草地和农用地分别为16.71gC/m2和16.54gC/m2;林地、草地、灌丛和农用地等不同植被类型季节变化表现出同样的特征:春季>秋季>冬季,其中林地植被NPP平均值冬季14.62gC/m2,春季增加到26.26gC/m2,秋季又有所减少,为18.79gC/m2,其它植被类型也表现出同样的季相变化特征,与当地气温和地表太阳辐射的季节变化基本相同。Simulation models are needed to study primary production of ecosystems with complex biological and environmental interactions at various temporal and spatial scales. The karst region in Guizhou has unique environmental conditions. Reestablishment of appropriate vegetation coverage is recognized as a fundamental measure for prevention of soil and water loss and restoration of degraded ecosystems. The primary productivity of different vegetation types and plant species under various environments reflects their adaptability to the environment. The study of primary productivity is an important basis for vegetation reconstruction and ecosystem restoration. Based on the Light Use Efficiency model and the soil water equilibrium model, we integrated actual field conditions into a coupling model. Soil moisture is introduced as a direct variable to the NPP model, so a direct relation between NPP and soil moisture can be established to predict the change in NPP when soil moisture changes. The comparisons with observed data illustrate that the coupling model can validly simulate the variation trends of net primary production （NPP） for typical karst ecosystems. We then used the model to study net primary productivity and its spatiotemporal pattern in a typical karst area of Guizhou Province from October 2006 to May 2007 using TM data, meteorological data and experimental observation data along with vegetation and soil texture information. Results show that there is a trend of NPP rising as vegetation cover increases in spatial distribution, and the mean value of vegetation NPP rises as plant activity increases. Different vegetation types have different NPP characteristics. The mean NPP of different vegetation types are in the following order： forest 〉 shrub 〉 grass 〉 cropland. The mean value of forest is 19.89 gC/m^2 , shrubland is 19.01 gC/m^2, and grass and cropland values are 16.71 gC/m^2 and 16.54 gC/m^2, respectively. The seasonal change in NPP is basically congruent with local temperature and terrestrial sol

关 键 词：植被净第一性生产力(NPP) 喀斯特 光能利用率模型 遥感技术 

分 类 号：Q948[生物学—植物学]