Spatial and Temporal Patterns of Net Primary Productivity from 1981 to 2000 in Shaanxi Province
To clarify the overall NPP change trends in Shaanxi Province, we estimate the NPP distribution pattern and time series using GLOPEM model driven by remote sensing observations. The results show:(l)The annual NPP ranged from 687 g/(m2·a) to 858 g/(m2 ·a) .and the mean value was 749 g/(m2·a) from 1981 to 2000 in Shaanxi Province. (2) The annual NPP of Shaanxi Province increased slowly with fluctuation, on an average, 3.248 2 g/(m2· a) annually. (3)The annual NPP declined from south to north. The minimum value of NPP was between 200 to 400 g/(m2· a) in the windy and sandy region along the Great Wall; The values of NPP in Central Shaanxi plain were higher,and most of them were above 800 g/(m2·? A). The NPP above 1 200 g/(m2·a) accounted for one third.and was high value region. (4)The regions of NPP remained basically unchanged (change rates between - 10% to 10%) were about 54. 7% of total Shaanxi. The regions of NPP with an increase of over 10% were about 40. 5% .and the regions of NPP reduced by 10% were only 4. 8%. (5)The regions of NPP with no significant difference (P>0. 05) were about 77.3% of total Shaanxi. The regions of NPP increased very significantly (P<0. 01) were about 8. 3%. The regions of NPP increased significantly (P<0. 05) were 13. 8%. The regions of NPP decreased significantly (P<0. 05)and the regions of NPP decreased very significantly (P<0. 01) altogether were 0. 7%.
net primary productivity (NPP)GLOPEM modeltemporal and spatial variationShaanxi Province
NETL
NSTL
万方数据
维普
