全球30米分辨率森林覆盖及变化数据集

本章基于全球30米分辨率森林覆盖变化产品（2000年和2018年）、全球500m分辨率森林净初级生产力（NPP）产品等，从全球、气候带以及洲际角度研究了2000—2018年森林覆盖及生产力时空变化分布特征，分析了本世纪以来全球森林覆盖变化与全球经济、人口发展、森林管理制度和管理目标的相关性。
21世纪以来，全球森林覆盖面积总体稳定略有下降，森林面积净减少0.17亿hm2，占全球森林总面积的0.44%。森林面积的增减表现出明显的区域差异。总体上，高收入发达国家的森林覆盖面积变化不大或有所增加，而部分低收入发展中国家和地区的森林面积则表现为大幅减少。另外，受极端气候以及大量的森林开发等因素的影响，热带地区是本世纪以来森林覆盖面积显著减少的区域，净减少森林覆盖面积达0.57亿hm²，随着中国生态恢复工程的大面积实施，2000—2018年间中国森林面积净增加0.45亿hm²，总面积达到2.12亿hm²，森林覆盖面积增长了26.90%。中国成为维持全球森林覆盖面积基本平衡的主要贡献者。
全球森林NPP总量整体呈缓慢下降趋势，下降量为4.63亿tC，下降幅度为1.33%，森林变化区（含毁林与造林）NPP下降了0.59亿t C。监测结果表明，2000年以来森林NPP急剧下降的区域主要集中在赤道附近的热带雨林地区。与中国森林覆盖面积增加相对应，中国区域森林NPP也显著上升，较2000年上升6.95%，这体现了中国生态保护工程及植树造林等举措对森林NPP增长的正面效应。

This chapter is based on global 30-meter resolution forest cover change products (for the years 2000 and 2018) and global 500-meter resolution forest Net Primary Productivity (NPP) products, among other datasets. It examines the spatiotemporal distribution characteristics of forest cover and productivity changes from 2000 to 2018 at global, climatic zone, and continental scales, and analyzes the correlations between global forest cover changes since the start of the 21st century and global economic development, population growth, forest management systems, and management objectives.

Since the start of the 21st century, the global forest cover area has shown an overall stable but slightly decreasing trend, with a net decrease of 17 million hectares, accounting for 0.44% of the total global forest area. The increases and decreases in forest area exhibit obvious regional disparities. Overall, forest cover areas in high-income developed countries have changed little or even increased, while forest areas in some low-income developing countries and regions have experienced sharp declines. In addition, affected by extreme weather events and large-scale forest exploitation, tropical regions have seen a significant reduction in forest cover area since the start of the 21st century, with a net decrease of 57 million hectares. With the large-scale implementation of China's ecological restoration projects, China's forest area increased by a net 45 million hectares from 2000 to 2018, reaching a total area of 212 million hectares, with a 26.90% growth in forest cover. China has become a major contributor to maintaining the basic balance of global forest cover area.

The total global forest NPP shows an overall slow downward trend, with a decrease of 463 million tonnes of carbon, corresponding to a 1.33% decline. The NPP in areas undergoing forest changes (including deforestation and afforestation) decreased by 59 million tonnes of carbon. Monitoring results indicate that regions with sharp declines in forest NPP since 2000 are mainly concentrated in tropical rainforest regions near the equator. Corresponding to the increase in China's forest cover area, the forest NPP in China has also increased significantly, rising by 6.95% compared to 2000, which reflects the positive effects of China's ecological conservation projects and afforestation measures on the growth of forest NPP.

搜集汇总

背景与挑战

背景概述

该数据集是一个全球范围的30米分辨率森林覆盖及变化栅格数据集，时间跨度为2000年至2018年，基于Landsat等遥感数据，采用随机森林算法生成，总体精度达90.94%。数据集分析了全球森林覆盖的时空变化，发现全球森林面积略有下降但区域差异显著，其中热带地区减少明显，而中国因生态工程森林面积大幅增加，成为维持全球森林平衡的主要贡献者。