SCIENTIA GEOGRAPHICA SINICA ›› 2012, Vol. 32 ›› Issue (9): 1106-1111.doi: 10.13249/j.cnki.sgs.2012.09.1106

• Orginal Article • Previous Articles     Next Articles

Spatio-temporal Pattern of Net Primary Productivity and Its Driven Factors in Northeast China in 1982-2010

De-hua MAO1,2(), Zong-ming WANG1, Ji-xing HAN1,2, Chun-ying REN1   

  1. 1.Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, Jilin 130012, China
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2011-12-23 Revised:2012-03-20 Online:2012-09-20 Published:2012-09-20

Abstract:

AVHRR NDVI at 8 km spatial resolution and MODIS NDVI at 1 km spatial resolution were integrated using per pixel linear regression model method to construct NDVI dataset from 1982 to 2010 at 8 km spatial resolution and covering Northeast China. Based on the constructed NDVI dataset and meteorological data, monthly net primary productivity in Northeast China in1982-2010 were estimated using the CASA model. Simulation accuracy of net primary productivity was above 75% and through accuracy and consistency check. Annual total vegetation net primary productivity in Northeast China is 6.5×108 t/a (carbon), and the distribution of net primary productivity varied from vegetation types, climatic and topography differences. There are obvious difference and spatial heterogeneity for NPP in Northeast China. For the vegetation in different topography areas, net primary productivity decreased in the order of mountains, plains, plateaus. For different vegetation types, net primary productivity decreased in the order of broadleaved deciduous forest and evergreen coniferous forest, mixed coniferous and broadleaved forest and deciduous coniferous forest, crop, grass. Trend analysis at pixel extent showed that the pixels with decreased trends mainly distributed in the transitional zone between typical forest zone and plain, Hulun Buir grassland and Chifeng semi-aird region. Result of spatial variation analysis showed that the NPP of grassland vegetation had the highest changes compared with other vegetation types in the past 29 years. But net primary productivity of grassland have an obvious increase at a whole, this was maybe resulted from the conservative grazing and grassland protection. Net primary productivity exhibited obviously increasing trend in 1982-2010. Consequently, vegetation carbon fixation had enhanced as a whole acquired from the decade analysis. Climatic changes for different parameters are very important affecting factors on spatial pattern and annual dynamic of NPP. Land cover changes in Northeast China during the past 29 years influenced the spatial pattern and annual dynamic for net primary productivity of different vegetation types. Economic development in this region still makes a pressure for vegetation net primary productivity, especially the forest.

Key words: NPP, AVHRR GIMMS NDVI, MODIS NDVI, CASA model, Northeast China

CLC Number: 

  • TP79