植被净初级生产力(NPP)指绿色植物在单位面积、单位时间内所累积的有机物数量。NPP作为地表碳循环的重要组成部分，不仅直接反映了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，而且是判定生态系统碳源/汇和调节生态过程的主要因子，在全球变化及碳平衡中扮演着重要的作用。近20多年来，随着温室效应等气候与环境问题的日益突出，以及相关政治外交谈判中对其科学依据的客观需要，越来越多的国家和学者参与到对陆地生态系统碳收支的时空格局及其变化趋势研究。 目前，国内外对生态系统净初级生产力及其生态环境效应已经取得了一定的进展和相当的成功，尤其在全球和全国大区域尺度范围内开展了较多的研究。本研究选取属于国际地圈—生物圈计划(IGBP)第15条样带的中国湖北省武汉市地区作为主要研究区域，该区域属于中亚热带常绿阔叶林向北亚热带落叶阔叶林过渡性地带。研究武汉区域陆地植被净初级生产力状况，对于了解和验证该样带亚热带落叶阔叶—常绿阔叶林植被净初级生产力具有十分重要的借鉴和生态意义。同时，对区域生态系统净初级生产力和碳汇研究、从大区域尺度上研究全国乃至全球碳循环起着一定的参考作用。 本文主要利用Landsat多时相遥感数据、相关气象数据及武汉市土地覆盖/利用分类数据资料，在建立陆地植被NPP遥感估算模型的基础上，重建了武汉市陆地生态系统1988-2002年NPP年际、年内变化的时空序列及不同植被种类NPP的分布与变化。 本文的第三章重点介绍了植被NPP光合曲线遥感估算模型的构建，详细论述模型参数因子(植被指数因子、标准光合因子、时间因子、呼吸作用因子)的选取与确定，同时将其与光能利用率模型进行比较，并通过地面实际样地测量结果对模型精度进行验证，从而得出本章的结论：1)基于通用模式分解方法的植被指数(VIUPD)在与植被密度、植土覆盖比以及光合速率的关系上，比归一化差值植被指数(NDVI)、增强植被指数(EVI)和基于模式分解方法的植被指数(VIPD)更加有效；2)植被的光合作用量与植被所能接收到的太阳光合有效辐射(PAR)有着极其密切的关系，利用多次地面同化箱实验数据，可拟合得到标准植被的有效光合辐射与植被光合成作用量关系曲线，建立光合作用量的估算模型；3)在模型建立的过程中，研究的往往只是瞬间的光合作用过程，因此，模型在时间尺度上存在延展性研究的问题；4)通过纪伊半岛地区的MODIS影像数据和地面实地观测数据解析，证明光合曲线估算模型对自然野生植被NPP遥感估算具有较好的精度。 在本文第四章中，利用地面分类数据、气象数据和卫星数据等资料，研究估算得到2002年研究区域内武汉市植被年NPP总量为2.63×10⁻³PgC/a，平均NPP为341.17 gC/m²/a，略高于全国2001年年均NPP的272.10 gC/m²/a。其中，常绿阔叶林年均NPP为637.07 gC/m²/a，落叶阔叶林的年均NPP为564.38 gC/m²/a，一年一熟农地年均NPP为397.99 gC/m²/a，一年多熟农地年均NPP为446.17 gC/m²/a。 将本研究成果与其它研究结果比较显示：依据国家森林普查结果，常绿阔叶林年均NPP约为14.41 t/hm²/a，即648.45 gC/m²/a；落叶阔叶林年均NPP约为5.83 t/hm²/a，即262.35 gC/m²/a。同本研究结果相比较，常绿阔叶林年均NPP较吻合，而落叶阔叶林年均值偏高。在彭少麟关于东部样带植被NPP的研究中，武汉市植被所属中亚热带常绿阔叶林地面实测139个样方点，其植被平均生产力为14.5 t/²a，即652.5 gC/m²/a。比较本研究得到637 gC/m²/a的常绿阔叶林年均NPP值，其结果一致。 在第五章中，我们主要就武汉市1988-2002年NPP年际、年内变化的时空序列及不同植被种类NPP分布与变化开展研究。研究发现，在全球环境变化的大背景下，武汉地区植被NPP在不断演化的过程中，有着一定的相对的稳定性和规律性。从大体趋势上而言，它符合全球环境变化的大趋势，但同时，它也具有自我区域性的小变化。从1988年到2002年的14年间，由于人口增长和经济发展，人类活动对武汉市地区NPP变化起着极为重要的作用。 关键词：净初级生产力；光能利用率模型；光合成曲线模型；土地覆盖/利用分类；多时相遥感影像。

Industrial development and human activities have greatly altered land cover over the past several decades. The increased cutting of forests and burning of fossil fuels have raised carbon dioxide concentrations in the atmosphere and has led to global temperature increases. Photosynthesis by vegetation removes carbon dioxide from the atmosphere and plays an important role in the carbon cycle. To measure net primary production (NPP) is a way to understand the photosynthesis capabilities of the vegetation. Great progress was made in the study of zonal NPP estimation, especially in world wide or in China, and its ecological environmental effect. In this study, Wuhan city of Hubei Province, China, was choosen as the study area. Wuhan city belongs to the 15th transect of IGBP and vegetative transition belt from mid-subtropical broad-leaved evergreen to north-subtropical broad-leaved decidous. It is important to estimate NPP of this area, for it could help us to understand the NPP situation of broad-leaved evergreen and decidous and the ecological environmental NPP and carbon budgets of this vegetative transition belt. In this paper, a method of integrating remote sensing data, ground meteorological data and other vegetation eco-physiological data to estimate NPP of a subtropical forest transition belt (Wuhan, China, mainly covered by subtropical forest). After the comparison and validation with observed data and other study results, the NPP time-series of Wuhan terrestrial vegetation from 1988 to 2002 was built. The spatio-temporal variations and potential trend of NPP, also the distribution and change of different kinds of vegetation NPP were analyzed in these 14 years. The third chapter focused on building NPP estimation model, which was made up of three parts like the factor of vegetation index, PAR, and temporal scale. Considering the relationship between vegetation index and LAI, vegetation cover ratio, photosynthetic rate, VIUPD was provided to be effective. And the model described the relationship curve between vegetation photosynthesis and photosynthetically active radiation through field measurement. It was applied to NPP estimation of Kii peninsula using multi-temporal satellite data, and yielded satisfied result in forest area estimation compared with field survey results. In the fourth chapter, Landsat TM/ETM+ data of 2002, ground meteorological data and other vegetation eco-physiological data were used to estimate NPP of Wuhan city. It is found that zonal gross NPP of Wuhan in 2002 is 2.63×10⁻³PgC/a and zonal annual NPP of Wuhan in 2002 is 341.17 gC/m²/a, which is little higher than average NPP of China in 2001. And the annual NPP of evergreen in 2002 is 637.07 gC/m²/a, while that of decidous is 564.38 gC/m²/a, that of one-harvest-a-yar is 397.99 gC/m²/a, and that of multi-harvest-a-year is 446.17 gC/m²/a. Comparing with observed data and other study results, it indicates that the estimated NPP in our study agrees with that using other estimation methods. The NPP time-series of Wuhan terrestrial vegetation from 1988 to 2002 was built in the fifth chapter. After analyzing the spatio-temporal variations and potential trend of NPP and the distribution and change of different kinds of vegetation NPP in these 14 years, we found that zonal NPP of Wuhan city changed steady and regular with the change of global environment. From 1988 to 2002, human activities played an important role in zonal NPP changing of Wuhan city, because of the sharp growth of population and development of economic. Key words: Net Primary Production; Light Utility Efficiency Model; Photosynthesis Curve Model; Land Use Classification; Multi-temporal remote sensing images.