时序遥感数据与生长模型结合的区域人工林地上生物量估算方法研究

Artificial forest occupy about 30% of forest land in China, the regional aboveground biomass (AGB) estimation of artificial forest and its yearly quantitative monitoring are very important for the researches on terrestrial ecosystem carbon cycle. Currently, AGB growth models based on forest resources inventor ignore the impact of site conditions and without accurate regional stand age, and can't use to directly estimate regional AGB for yearly quantitative monitoring. In addition, the methods for AGB estimation using remote sensing data always focus on a single images, and get instantaneous production. In this study, we plan to use the advantages of high resolution optical remote sensing data and LiDAR, especially for more than 40-year Landsat data and other temporal images or products, and develop the methods to map regional stand age of artificial forest after quantitative processing for temporal images. Moreover, we analyze the relationships between the seasonal phenological and interannual variation information of artificial forest, as well as the variation of site parameters, and then built the remote sensing variables to find out the impacts of site condition on forest growth. Finally, we develop AGB growth models integrating the regional stand age and remote sensing variables for regional AGB estimation. Our models are able to produce artificial forest AGB product with the moderate spatial resolution of 30m and high temporal resolution of 1-year over past about 40 years, this product will provide the theoretical and data support for regional carbon cycle and forestry policy decisions in China.

人工林约占我国有林地30%，其区域地上生物量估算及时序定量监测是我国陆地生态系统碳循环等研究的重要组成部分。当前，森林资源清查方法建立的生长模型没有考虑立地条件影响，且缺少有效的区域尺度林龄数据，难以直接进行区域森林地上生物量时序定量监测；而广泛使用的遥感方法多集中于单期影像，生成数据产品为某一时间点的。针对以上问题，本研究基于高分光学遥感与机载小光斑激光雷达数据优势，主要利用40多年Landsat系列卫星等时序遥感影像，研究定量化处理及区域林龄提取方法。结合立地因子，分析人工林遥感参量年内物候及年际变化信息，提取反映立地因子对区域人工林生长影响的遥感参量。应用区域林龄与生长状况遥感监测参量，构建新的生长模型，研究区域人工林地上生物量估算方法。此方法可实现我国三北防护林典型地区近40年、30米分辨率、逐年的人工林地上生物量动态监测，为区域碳循环研究及国家林业政策制定提供理论与数据支持。

人工林约占我国有林地30%，其区域地上生物量估算及时序定量监测是我国陆地生态系统碳循环等研究的重要组成部分。当前，森林资源清查方法建立的生长模型没有考虑立地条件影响，且缺少有效的区域尺度林龄数据，难以直接进行区域森林地上生物量时序定量监测；而广泛使用的遥感方法多集中于单期影像，生成数据产品为某一时间点的。针对以上问题，本研究主要利用40多年Landsat系列卫星等时序遥感影像，研究定量化处理及区域林龄提取方法。结合立地因子，分析人工林遥感参量年内物候及年际变化信息，提取反映立地因子对区域人工林生长影响的遥感参量。应用区域林龄与生长状况遥感监测参量，构建新的生长模型，研究区域人工林地上生物量估算方法。此方法可实现我国三北防护林典型地区近40年、30米分辨率、逐年的人工林地上生物量动态监测，为区域碳循环研究及国家林业政策制定提供理论与数据支持。