基于CASA模型的长顺县夏季NPP时空格局

Spatial and Temporal Patterns of Summer Net Primary Productivity( NPP ) in Changshun Based on CASA Model

基于CASA模型估算了长顺县夏季植被净初级生产力(NPP),并分析了2000~2011年期间其时空分布特征。研究表明:2000~2011年期间,长顺县夏季NPP平均为34.51 g C/m^2·m,全县91.65%的区域,NPP值在20~50 g C/m^2·m之间。多年平均夏季NPP的分布呈现明显的地域性差异,总体呈现出由中部落叶阔叶林、针阔混交林及灌木林等植被茂盛的区域逐渐向东西两侧耕地及建设用地区域减少的分布规律;夏季NPP在12年间,其变化整体呈缓慢上升趋势。针阔混交林、落叶阔叶林、灌木林、耕地及草地区域的平均增长率分别为2.77、2.32、2.34、0.99、1.05。地区植被在夏季的固碳量在逐年增加;各乡镇夏季平均NPP在12年内的变化一致。长寨镇、广顺镇、摆所镇、鼓扬镇、代化镇、改尧镇、敦操乡分别以2.16、1.88、2.10、2.17、2.29、2.12、2.51 g C/m2·m的速率增加。

Based on the CASA model, the net primary productivity （NPP） of summer vegetation in Changshun County was estimated, and the temporal and spatial distribution characteristics of the vegetation in 2000 - 2011 were analyzed. The results showed that the average NPP in Changshun County was 34.51gC / m^2 · m in the period from 21300 to 2011, and the area of NPP was between 20 - 50gC / m^2 ·min 91.65% of the county. The distribution of average NPP in summer showed obvious regional differences, and The distribution pattern was gradually decreased from the lush vegetation of the central deciduous broad - leaved forest, coniferous and broad - leaved mixed forest and shrub forest to the east and west sides of the cultivated land and the construction land area. Summer NPP changed in a slow upward trend on the whole in 12 years. The average growth rates of coniferous and broad-leaved mixed forest, deciduous broad-leaved forest, shrub forest, arable land and grassland were 2.77, 2.32,2.34, 0.99, and 1.05 respectively. The average carbon fixation of regional vegetation in summer increased year by year. The average summer NPP had a similar trend in the townships in 12 years. NPP in Changzhai, Guangshun, Baisuo, Guyang, Daihua, Gaiyao and Duncao increased at rate of about 2.16, 1.88, 2.10, 2.17, 2.29, 2.12, 2.51 gC/m^2· m respectively.