ABSTRACT

The tropics are greening, but little is known about greening patterns in the tropical Andes. Using Normalized Difference Vegetation Index (NDVI) data on monthly and annual bases, this research analyzes greening across Ecuador from 1982–2010. Findings indicate overall significant greening after the mid ’90s with distinct seasonal variations across regions. In the Amazon greening occurs during months of low precipitation, resulting in a prolonged growing season and higher NDVI peak from the ’80s to the 2000s. A similar albeit less pronounced trend is observed in the eastern part of the Andes but during high rainfall. Different patterns are evident in western regions. In coastal Ecuador and the western Andes, no lengthening of the growing season occurs; greening occurs only in the coast due to increases in NDVI from the ’80s to the 2000s. These findings highlight the importance of sub-regional studies to further understand tropical vegetation greening and its drivers.

摘要

热带地区正在绿化，但对热带安第斯山脉的绿化模式知之甚少。使用月度和年度基准上的归一化植被指数（NDVI）数据，本研究分析了1982-2010年厄瓜多尔的绿化情况。调查结果表明，90年代中期以后总体上出现了明显的绿化现象，各地区之间的季节变化也明显不同。在亚马逊地区，绿化发生在降雨量低的月份，导致生长季节延长，并且从80年代到2000年代的NDVI峰值更高。在安第斯山脉的东部，但在高降雨期间，观察到了类似的趋势，尽管趋势不太明显。西部地区有不同的模式。在厄瓜多尔沿海地区和安第斯山脉西部，生长季节没有延长。由于从80年代到2000年代NDVI的增加，仅在沿海地区发生了绿化。