作为陆地生态系统的主体,森林的碳循环与碳蓄积对研究陆地生态系统起着重要作用,但目前森林扰动资料的缺乏在很大程度上影响着森林碳通量的估算精度。利用1986年-2011年共14期的Landsat TM/ ETM+影像,以江西武宁县为例,使用遥感指数时间序列轨迹分析方法,研究了适用于中国南方森林的扰动监测技术,该技术不仅可以识别森林的扰动变化,同时还可以监测植被的恢复信息。精度分析表明该方法得出的扰动产品的Kappa系数达到0.80,总体精度达到89.7%,表明该方法对武宁县森林扰动具有较好的监测能力。森林扰动特征分析表明武宁县森林在20世纪90年代受扰动最为剧烈,并且扰动主要发生在低海拔地区。

Forest ecosystems, which are major parts of the terrestrial biosphere, play an important role in terrestrial carbon cycling and storage. However, the accuracy of forest carbon-flux estimation is greatly influenced by the lack of forest disturbance data. Thus, we conduct a study in Wuning County in Southern China by adopting a time-series trajectory analysis technique to detect forest disturbances in 14 Landsat Thematic Mapper/Enhanced Thematic Mapper Plus images from 1986 to 2011. This technique not only identifies forest disturbance, but also provides vegetation recovery information. By analyzing the time-space disturbance characteristics of forest disturbance, we found that Wuning County has suffered from a significantly dramatic disturbance in the 1990s, most of which has occurred in low-elevation areas because of human activities. Compared with field observations, the Kappa coefficient of our disturbance products reaches 0.80 with an overall accuracy of 89.7%, thus indicating the significant potential of the technique for forest disturbance monitoring.