利用CASA模型,结合实测的光合有效辐射(PAR)数据、MODIS归一化植被指数(NDVI)和Land Cover数据、气象数据等资料,估算了2009年武汉市的植被净初级生产力(NPP)。结果显示,武汉市的植被平均单位面积年NPP产量达到464.19gC·m^-2·a^-1。6、7、8三个月NPP积累值最高,占全年的56.8%;12、1、2三个月NPP值最低,仅占5.6%。黄陂区由于林地较广,NPP值较大,在1 000gC·m^-2·a^-1以上;而城市周边由于植被覆盖面积较小,NPP值较低,在400gC·m^-2·a^-1以下。
The net primary productivity of vegetation of Wuhan City in 2009 was estimated by the CASA model with measured photosynthetic active radiation data,normalized difference vegetation index and Land Cover data of Moderate Resolution Imaging Spectroradiometer(MODIS),as well as meteorological data etc.The results shows that the NPP of the unit area of vegetation is 464.19 gC·m^-2·a^-1.And,the accumulated NPP of June to August is 56.8% of the gross NPP of the full year,which is the highest compare to that of other months.On the contrary the accumulated NPP of December to February is 5.6% of the gross NPP,which is the lowest compare to that of other months.Further more,the gross NPP of Huangpi is larger than 1 000 gC·m^-2·a^-1 due to its large area of forest cover.Conversely,the gross NPP of peri-urban area is lower than 400 gC·m^-2·a^-1 because of the shortage of vegetation cover.