气候变化背景下鄱阳湖地区植被覆盖及生产力变化研究

Spatial Characteristics of Vegetation Cover and NPP Change under Climate Change in Poyang Lake Area

利用1981～2000年鄱阳湖地区的气象台站数据、NOAA／AVHRR—NDVI数据集（空间分辨率为8km）以及光能利用率模型GLO—PEM模拟的鄱阳湖地区植被净第一性生产力（NPP）（空间分辨率为1km），基于最小二乘法，分析了全球变化背詈下该地区均温和降水、年最大植被指数（NDVImax）以及年NPP的年际变化趋势，探讨了植被年NDVImax、NPP变化与气候变化的关系。结果表明，近年来鄱阳湖地区气候变化比较显著，年均温和年降水量均呈现显著上升趋势，但变化幅度存在着明显的区域差异。1980～2000年闰鄱阳湖大部分地区年NDVimax存在增加趋势，但也有少部分地区呈降低趋势，其中增加趋势的显著性水平相对较高，而降低变化趋势不够显著。1980～2000年，鄱阳湖地区NPP变化主要呈现增加趋势，且显著性水平较高；其中，整个鄱阳湖地区NPP年变化率为111257t／年．滨湖区为49920t/年，外围区为61337t／年；在离湖不同缓冲距离上，NPP变化的趋势基本一致。鄱阳湖地区气候暖湿化发展对植被改善具有一定的促进作用。

Utilizing climatic data （temperature and rainfall） from meteorological station, NDVI （Normalized Difference Vegetation Index, AVHRR NDVI product of 8 km） and net primary productivity （ NPP of 1 km） simulated by GLO-PEM model in the region of Poyang Lake from 1981 to 2000, this study assessed the trend of climate （e. g. annual mean temperature and annual rainfall）, yearly biggest NDVI and yearly NPP change, the relationship between NDVI and climate factors, the relationship between NPP and climate factor. The results showed that ： in recent years, the annual mean temperature and annual rain has increased obviously in the region of Poyang Lake, but the change range was different in different areas; from 1982 to 2000, the yearly biggest NDVI has increased obviously in the most areas of Poyang Lake; but in a few areas, it showed a decreasing tendency and did not pass the significance test ; the NPP of Poyang Lake displayed an increasing tendency from 1980 to 2000, the increasing range of the whole Poyang Lake, the lakefront region and the marginal area was 111 257 t/a, 49 920 t/a and 61 337 t/a, respectively ; in the different buffer zones from the lake, the change of NPP had the same change tendency, which showed that the climate played an important role in the vegetation growth in the region of Poyang Lake.