# Mapping Paddy Rice in China in 2002, 2005, 2010 and 2014 with MODIS Time Series
## 4 Results
### Rice Area Change  
In addition to the accuracy assessment, the extracted rice areas from our classifications for each province and the years 2002, 2005, 2010 and 2014 were used to quantify rice area changes. For each province, we compared the classified rice area to the previous classification and calculated the percentage of change (Table 3). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **OCSVM\({}_{2002}\)** & **\%\(\Delta\)** & **OCSVM\({}_{2005}\)** & **\%\(\Delta\)** & **OCSVM\({}_{2010}\)** & **\%\(\Delta\)** & **OCSVM\({}_{2014}\)** \\ \hline Anhui & 1661.87 & 13.2\% & 1880.88 & 2.0\% & 1919.38 & \(-\)1.6\% & 1888.12 \\ Beijing & 0.37 & 213.0\% & 1.16 & \(-\)92.1\% & 0.09 & 411.8\% & 0.47 \\ Chongqing & 988.88 & \(-\)11.0\% & 880.42 & \(-\)7.6\% & 813.25 & \(-\)13.2\% & 706.31 \\ Fujian & 614.00 & \(-\)23.3\% & 470.66 & 13.6\% & 534.67 & \(-\)27.1\% & 389.77 \\ Gansu & 3.55 & 17.1\% & 4.16 & \(-\)39.1\% & 2.53 & \(-\)30.1\% & 1.77 \\ Guangdong & 1341.08 & \(-\)3.0\% & 1301.10 & \(-\)14.9\% & 1106.62 & \(-\)1.0\% & 1095.24 \\ Guangxi & 1327.83 & \(-\)11.8\% & 1170.50 & \(-\)15.4\% & 990.57 & 7.8\% & 1068.04 \\ Guizhou & 911.36 & \(-\)3.8\% & 876.46 & \(-\)12.1\% & 770.78 & \(-\)5.1\% & 731.33 \\ Hebei & 58.56 & 157.3\% & 150.68 & \(-\)75.6\% & 36.70 & 115.3\% & 79.01 \\ Heilongjiang & 903.25 & 18.5\% & 1070.44 & 84.3\% & 1972.52 & 29.8\% & 2560.05 \\ Henan & 430.92 & 61.1\% & 694.32 & 8.4\% & 752.34 & 3.6\% & 779.70 \\ Hubei & 1607.90 & \(-\)6.2\% & 1508.79 & 3.1\% & 1555.39 & 3.8\% & 1614.46 \\ Hunan & 1721.73 & \(-\)5.2\% & 1631.84 & \(-\)2.6\% & 1589.40 & \(-\)0.2\% & 1586.33 \\ Inner Mongolia & 31.58 & 17.4\% & 37.06 & \(-\)27.8\% & 26.74 & 133.3\% & 62.38 \\ Jiangsu & 2191.33 & 6.8\% & 2340.44 & \(-\)15.7\% & 1973.68 & 21.5\% & 2397.08 \\ Jiangxi & 1411.43 & 16.2\% & 1640.37 & 5.3\% & 1726.94 & \(-\)1.6\% & 1698.67 \\ Jilin & 405.49 & \(-\)10.4\% & 363.27 & \(-\)21.1\% & 286.75 & 35.8\% & 389.40 \\ Liaoning & 381.79 & \(-\)0.3\% & 380.63 & 26.6\% & 466.58 & 0.7\% & 469.83 \\ Ningxia & 31.62 & 17.8\% & 37.25 & 3.0\% & 38.37 & 66.7\% & 63.98 \\ Qinghai & 1.05 & 65.1\% & 1.73 & 29.2\% & 2.23 & \(-\)42.8\% & 1.28 \\ Shaanxi & 202.10 & \(-\)36.7\% & 127.99 & 37.3\% & 175.79 & \(-\)15.0\% & 149.40 \\ Shandong & 210.33 & \(-\)5.5\% & 198.75 & \(-\)20.1\% & 158.83 & \(-\)4.5\% & 151.70 \\ Shanghai & 30.60 & 54.2\% & 47.19 & \(-\)15.3\% & 39.96 & 31.7\% & 52.64 \\ Shanxi & 2.98 & 39.2\% & 4.15 & 79.6\% & 7.46 & 83.6\% & 13.70 \\ Sichuan & 1819.26 & 30.0\% & 2364.76 & \(-\)26.9\% & 1727.51 & 2.2\% & 1766.03 \\ Tianjin & 6.96 & 200.5\% & 20.92 & \(-\)76.3\% & 4.96 & 207.1\% & 15.25 \\ Tibet & 1.21 & \(-\)9.3\% & 1.10 & 54.1\% & 1.70 & 7.9\% & 1.83 \\ Xinjiang & 6.92 & 253.0\% & 24.44 & 5.4\% & 25.75 & 22.2\% & 31.46 \\ Yunnan & 1223.81 & \(-\)5.4\% & 1157.71 & \(-\)0.1\% & 1156.06 & \(-\)5.4\% & 1093.33 \\ Zhejiang & 864.80 & 0.6\% & 870.03 & \(-\)7.7\% & 803.00 & \(-\)15.6\% & 677.77 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Rice area and change per province in 1000 ha derived from our classifications. Figure 6: R\({}^{2}\) for OCSVM\({}_{2010}\), OCSVM\({}_{2005}\) and OCSVM\({}_{2002}\) compared to _Sovan Area_ of rice for the season with the largest extent (**a**) and _Total Sovan Area_ for provinces with one dominant rice crop per year (**b**). Our classifications show that the paddy rice area for continental China constantly exceeded 20,000 kha. Paddy rice area in 2002 was 20,394.56 kha and increased by 865 kha to 21,259.20 kha in 2005. From 2005-2010, the rice area was reduced by 593 kha to 20,666.55 kha. The year 2014 had the largest rice area of our study period with 21,536.33 kha, an increase of 870 kha compared to 2010 and 1142 kha when compared to the rice area of 2002. From 2002, through 2005 and 2010, and to 2014, the change in rice area for continental China never exceeded 5% from one classification to the other. While the overall paddy rice area remained largely stable, we can observe shifts in rice area of the provinces (Figure 7).