TY - JOUR
T1 - Analysis of the spatial variation in the net ecosystem production of rice paddy fields using the diagnostic biosphere model, BEAMS
AU - Sasai, Takahiro
AU - Nakai, Saori
AU - Setoyama, Yuko
AU - Ono, Keisuke
AU - Kato, Soushi
AU - Mano, Masayoshi
AU - Murakami, Kazutaka
AU - Miyata, Akira
AU - Saigusa, Nobuko
AU - Nemani, Ramakrishna R.
AU - Nasahara, Kenlo N.
N1 - Funding Information:
This study was supported in part by the National Institute for Environmental Studies and by the Japan Aerospace Exploration Agency Global Change Observation Mission – Climate project under Contract 102: “Development of integrative information of the terrestrial ecosystem”, a Japanese Ministry of Education, Culture, Sports, Science, and Technology Grant-in-Aid for Young Scientists (B) (No. 20710018 ) and Scientific Research (B) (No. 23310015 ), and the Global Environmental Monitoring, Center for Global Environmental Research .
PY - 2012
Y1 - 2012
N2 - To realistically understand spatial and temporal variations in the net ecosystem production (NEP) of rice paddies in Japan, we enhanced the existing diagnostic-type biosphere model with the addition of agricultural processes. Validated with a comparison of seasonal and annual variations over 5 years, the NEP estimations bore good agreement with the measurements. In regional-scale analyses, we targeted all rice paddy fields in Japan from January 2001 to December 2009. Before and after the model enhancement, the NEP showed very different spatial variations and absolute values, suggesting that the most effective improvements were the introduction of harvest and soil oxidation-reduction processes. In annual anomaly analyses covering a 9-year period, the NEP was found to be negative in 2003 and 2006 (-0.11 and -0.25. TgC/year) and positive in 2004 and 2007 (+0.02 and +0.21. TgC/year). We found that the negative values were caused by decreases in solar radiation and air temperature and the positive values were caused by increases in these two parameters and precipitation. In response to the NEP, our obtained harvested grain biomass values in 2003 and 2006 were lower than usual. The results were in good agreement with the results from reports of the Japan Meteorological Agency and the Ministry of Agriculture, Forestry, and Fisheries.
AB - To realistically understand spatial and temporal variations in the net ecosystem production (NEP) of rice paddies in Japan, we enhanced the existing diagnostic-type biosphere model with the addition of agricultural processes. Validated with a comparison of seasonal and annual variations over 5 years, the NEP estimations bore good agreement with the measurements. In regional-scale analyses, we targeted all rice paddy fields in Japan from January 2001 to December 2009. Before and after the model enhancement, the NEP showed very different spatial variations and absolute values, suggesting that the most effective improvements were the introduction of harvest and soil oxidation-reduction processes. In annual anomaly analyses covering a 9-year period, the NEP was found to be negative in 2003 and 2006 (-0.11 and -0.25. TgC/year) and positive in 2004 and 2007 (+0.02 and +0.21. TgC/year). We found that the negative values were caused by decreases in solar radiation and air temperature and the positive values were caused by increases in these two parameters and precipitation. In response to the NEP, our obtained harvested grain biomass values in 2003 and 2006 were lower than usual. The results were in good agreement with the results from reports of the Japan Meteorological Agency and the Ministry of Agriculture, Forestry, and Fisheries.
KW - BEAMS
KW - Biosphere model
KW - Carbon cycle
KW - NEP
KW - Remote sensing
KW - Rice paddy
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U2 - 10.1016/j.ecolmodel.2012.08.016
DO - 10.1016/j.ecolmodel.2012.08.016
M3 - Article
AN - SCOPUS:84870226168
VL - 247
SP - 175
EP - 189
JO - Ecological Modelling
JF - Ecological Modelling
SN - 0304-3800
ER -