APP下载

重庆市植被净初级生产力的遥感估算及分析

2016-10-21简太敏

安徽农业科学 2016年4期

简太敏

摘要[目的]遥感估算和分析2007年重庆市植被净初级生产力(NPP)。[方法]基于CASA模型,结合SPOT/VEGETATION NDVI S10 数据、植被覆盖分类图、气象数据等,对2007年重庆市NPP进行遥感估算,在GIS及RS的支持下,进行数据的前期处理,对2007年重庆市NPP分布状况及年内变化情况进行分析。[结果] NPP平均值为112.343~799.391 g C/m2,研究区植被净初级生产力区域变化明显,季相差异显著,其中高值主要出现在渝东南、东北区域,低值主要存在于渝西北区域;NPP值夏季(6~8月)﹥春季(3~5月)﹥秋季(9~11月)﹥冬季(12~2月),年内阔叶林植被NPP最高,水生植被NPP生产量最低。[结论] 该NPP估算方法能较好地模拟重庆市的NPP及其时空格局,估算结果比较符合实际,能应用于NPP估算项目中。

关键词植被净初级生产力;CASA模型;遥感估算;重庆市

中图分类号S181文献标识码A文章编号0517-6611(2016)04-080-03

Remote Sensing Estimation and Analysis of Vegetation Net Primary Productivity in Chongqing City

JIAN Taimin(Ningxia Normal University, Guyuan, Ningxia 756099)

Abstract[Objective] To estimate and analyze the vegetation net primary productivity (NPP) in Chongqing City by remote sensing. [Method] Based on CASA model, remote sensing estimation of NPP in Chongqing in 2007 was carried out by using meteorological data, SPOT/VEGETATION NDVI S10 data and vegetation classification figure. Under the support of GIS and RS, data pretreatment was adopted, and NPP distribution and change situation were analyzed in Chongqing in 2007. [Result] The NPP average value was 112.343-799.391 gC/m2; vegetation NPP changed significantly in research region; seasonal differences were significant. The high values appeared in southeast and northeast areas of Chongqing; while low values appeared in northwest Chongqing. The NPP values were in the order of summer (JuneAugust)﹥ spring (MarchMay) ﹥ autumn (SeptemberNovember) ﹥ winter (December -February). NPP of broadleaved forest vegetation was the maximum; but NPP of aquatic vegetation was the minimum. [Conclusion] This NPP estimation method can simulate the NPP in Chongqing City and its spatial and temporal pattern. The estimation results are relatively realistic, and can be used for the NPP estimation.

Key wordsNet Primary Productivity (NPP); CASA model; Remote sensing estimation; Chongqing

植被净初级生产力(Net Primary Productivity,NPP)是指绿色植物在单位面积、单位时间内所累计的有机物数量,是由光合作用所产生的有机质总量扣除自养呼吸后的剩余部分[1-2],通常以干重表示。NPP作為地表碳循环的重要组成部分,不仅直接反映植被群落在自然环境条件下的生产能力,表征陆地生态系统的质量状况,还是判定生态系统碳汇和调节生态过程的主要因子[3],在全球变化及碳平衡中起着重要作用。自20世纪60年代国际地圈-生物圈(International GeosphereBiosphereProgramme,IGBP)计划以来,全球及区域NPP得到了大规模研究,IGBP和全球变化与陆地生态系统(GCTE)和京都议定书中均把植被的NPP研究确定为核心内容之一[1]。近年来,各国学者进行了大量的植物NPP测定,且以测定资料为基础,结合气候环境因子建立模型,对植被NPP的区域分布进行评估。……

登录APP查看全文