Abstract

Satellite remote sensing was combined with the NASA-CASA (Carnegie Ames Stanford Approach) carbon cycle simulation model to evaluate the impact of the 2010 drought throughout China. Results indicated that net primary production (NPP) for 2010 declined most notably in the provinces of Xinjiang, Hebei, and Zhejiang, predominantly in cropland and mixed forest areas. Annual NPP in the most drought-impacted areas of southwestern China declined by an average of 13% compared to the previous 10-year average. The greatest decline in total ecosystem carbon gain during 2010 (compared to 2000 to 2009) was detected in the provinces of Yunnan (-28.1 Tg C), Tibet (-18.8 Tg C), and Guizhou, (-6.3 Tg C) predominantly in cropland, grassland, and mixed forest areas. Despite these drought impacts over the southwest and northern regions, the CASA model estimated that China gained total ecosystem carbon in 2010 at double the mean annual rate (computed for the period 2000 to 2009). Cropland and forest areas of Heilongjiang and Inner Mongolia remained productive in 2010 and these regions were estimated, along with several other provinces, to offset and exceed declines in plant production and total ecosystem carbon losses in the most drought-impacted areas of Tibet, Guizhou, Yunnan, Xinjiang, and Zhejiang provinces.

Keywords: China; Drought; carbon cycle; MODIS