Proceedings Article | 8 November 2014
KEYWORDS: Vegetation, MODIS, Data conversion, Factor analysis, Data centers, Statistical analysis, Remote sensing, Climatology, Binary data, Spatial resolution
Based on the MODIS NPP data, terrain data, and land cover map, spatio-temporal pattern of NPP in Wuling
mountainous area during 2001-2010 and its relationships with the elevation and slope were analyzed using regression
analysis and classification statistics. Results showed that the average annual NPP of the study area from 2001 to 2010
was 590.72 g C m-2 yr-1. The mean NPP of forest, shrub/grassland, and cropland were 596.79 g C m-2 yr-1, 586.98 g C m-2
yr-1, and 563.31 g C m-2 yr-1, respectively. During 2001-2010, the average annual total NPP of Wuling mountainous area
was 98.90 T g C yr-1, ranging from 92.79 T g C yr-1 to 106.99 T g C yr-1. Besides, the spatial pattern of interannual
variability of NPP in the north of our study area presented a significant increase trend while in the south it displayed an
opposite tendency. According to the relationships between mean NPP and elevation as well as slope at steps of 30m and
3°, respectively, NPP increased with the altitude and slope first, then decreased slowly, but when the elevation above
1500m or the slope greater than 50°, the mean NPP presented large fluctuations. However, on the whole, mean NPP
increased with the altitude and slope first, then decreased again. Additionally, mean NPP within elevation range of
200m-1000m and slope range of 5°-25° were relatively high, but it decreased one after another in the zones above 500m
and had a trend of increase when the slope zones greater than 50°, which reflected the erosion intensity was weakened
when the slope greater than a certain threshold.
