基于多源长时序遥感大数据的中国橡胶林动态研究

中国橡胶快速增长了数十年,已大面积延伸到高海拔和陡峭山坡等次适宜地区，而当下因价格持续低迷面临大面积削减的压力。橡胶种植已经显著改变并将继续影响我国热区的景观结构，其潜在生态问题已在西双版纳(约占云南橡胶总面积52%)热点地区引发国内外学者的高度关注。但在国家尺度，由于利于橡胶遥感识别的物候期非常短暂、热区无云光学影像匮乏等因素限制而鲜有研究，以至于对中国橡胶的扩张模式及生态影响的认识还极为有限。本项目拟采用多源和长时间序列遥感数据,辅以野外调查，在谷歌Earth Engine云平台通过物候、光谱和结构等特征分析及数据挖掘，建立国家尺度的橡胶林识别算法，生成多期数据产品，揭示中国橡胶近三十年的时空变化特征，阐明格局变化的驱动机制。通过探索大尺度的橡胶监测技术手段，明确中国橡胶过去和当前分布现状、次适宜地区橡胶的比重及格局，为橡胶产业规划、客观评价橡胶扩张的生态效应等提供数据支撑和决策依据。

The area of rubber plantation in China has grown rapidly for decades, which have been predominantly spreaded into potentially sub-optimal environments of higher elevation and steeper slopes, and now facing pressure of largely cut-down due to continually depression of natural rubber price. The rapid expansion of rubber plantation especially after 2000 has been significantly changed and will continue to affect the structure and landscape of tropics in China. The potential ecological and environmental problems of rubber expansion in Xishuangbanna, a worldwide hotspot region which consist about 52% of total rubber area in Yunnan province, has raised wide concern by scholars form domestic and abroad. However, almost no study was conducted at national scale mainly due to the phenology that good for rubber identification is very short and the limited cloud-free optical imagery in tropical area. Therefore, we still have little knowledge about the spatial-temporal distribution of rubber plantation and its ecological impacts. In this study, we intent to integrate multi-source and long time series remote sensing data and filed investigation data, and to develop a national scale mapping algorithm through analyzing the phenology, spectrum and structural characteristics of rubber plantation as well as data mining technology on Google Earth Engine. Then, we apply the algorithms to generate multi-period rubber distribution products, and to study the spatio-temporal of rubber expansion in past 30 years as well as driving mechanism. The development of national scale mapping algorithm, the understanding of rubber distribution from the past to present, especially the area and pattern of rubber plantation in sub-optimal environments, would greatly help the decision making in rubber industry and the ecological studying of rubber expansion in China.