Spatio-temporal Patterns of Net Primary Production(NPP) in Weihe
Watershed(China) and its Response to Environmental Factors
Abstract
Carnegie-Ames-Stanford Approach and CA-Markov models are coupled to
simulate and predict NPP in the Weihe Watershed to explore the spatial
and temporal distribution of NPP and its dynamic changes. Correlation
analysis was used to quantitatively evaluate the NPP response to
environmental factors.Results showed that: (1) Seasonal and periodic
changes were evident within a year. The interannual change showed a
rising trend. According to forecast results, the NPP status of
vegetation in the Weihe Watershed will improve and continue to grow over
the next decade. (2) Spatially, the NPP distribution is significantly
different, showing an overall high distribution in the south and east
and low distribution in the north and west. (3) The response of
vegetation NPP in the Weihe Watershed to environmental factors is
significant but varied. The NPP response to temperature and
precipitation was mildly positively correlated. The NPP showed trends of
stabilizing, then sharply decreasing, and finally increasing with the
increase in altitude, as well as continuously increasing with the
increase in slope. Meanwhile, the vegetation NPP values of the northern
and western slopes were higher than those of the southern and eastern
slopes. (4) The CASA and CA-Markov models have high coupling degrees.