近40年气候变化对江西自然植被净第一性生产力的影响

根据全球气候变化的趋势，采用植被净第一性生产力模型，对江西省南昌、吉安、赣州3地近40年气候变化对自然植被净第一性生产力（NPP）的影响进行研究，并模拟了3地自然植被NPP在未来气候3种水热条件下的变化趋势。此外还以1980年江西全省自然植被NPP为例分析了自然植被NPP的区域分布特征，结果表明：3地近40年自然植被NPP平均值分别为1319 、1311和1320 t/hm2〖DK1〗·a，总体上都呈上升的趋势。 当年均气温增加2℃且降水量增加20%时，NPP值增加了149%~1585%；随着年均气温增加2℃且降水量减少20%，NPP减少了477%~516%；当年均气温增加2℃且降水量不变时，NPP增加了530%~569%。江西自然植被NPP区域分布特征由东、南、西3个方向向北呈放射状分布，随着地形由高山向丘陵、平原的方向变化而减小。

IMPACT OF CLIMATIC VARIATION ON NET PRIMARYPRODUCTIVITY OF NATURAL VEGETATION IN JIANGXIIN RECENT 40 YEARS

According to the trend of global climate changes,impact of climatic variation on net primary productivity (NPP) of natural vegetation in three regions，Nanchang,Ji'an and Ganzhou，in Jiangxi Province in recent 40 years was studied.The change trend was simulated based on combinations of thermal and hydrological conditions.Also,NPP pattern of the whole region of Jiangxi Province was analyzed with vegetation productivity in 1980s.The average values of NPP in the three regions during past 40 years were 1319,1311,and 1320 t/hm2〖DK1〗·a,respectively,showing an overall tendency of slight increase.Based on the presumption that the temperature and precipitation increased by 2℃ and 20%,respectively,the value of NPP would ascend by 149%~1585%.When the temperature and precipitation increased by 2℃ and -20%,respectively,it would decreased by 477%~516%.For the scenario of increased temperature (+2℃) and unchanged precipitation,the increase of NPP was predicted as 530%~569%.A radius form from the center to east,south and west characterized the spatial pattern of NPP distribution,and it declined from mountains to hills and plains.