粮食安全与耕地资源变化的相关分析.doc

21 21 F062.1A10003037(2001)040313071 12319951998 14.1% 18.1% 17%18% 8 4 21 2 2.1 10107t 1949 1998 4 1998 5.123108t 410kg 1949 2 400kg 21 !-empirenews.page-2.2 8.3108t5 1998 1.62 673 3.1 8 1.3108hm29 14.2% 0.11hm2 1/2 2/3 1/310 1% 2.5%4.0% 81 0.33108hm211 0.133108hm2 0.50.6 0.067108hm20.08108hm2 !-empirenews.page-123.2 1 19561957 1995 9500hm2 43.14hm2 1949 5.4 1998 12 1 19491995 Fig.1 Change trends of total and per capita cultivated area during 19491995 21 30 15 16 53.3 131 1997 1.33105hm2 94 !-empirenews.page-144.1 19501995 2 195919601985 3 39 78.26% 5.86% 211.11% 21.74% 5.77% 57.69% 2 Fig.2 Annual change rate of cultivated area and annual growth rate of grain production 3 Fig.3 Trends of annual cultivated area change rate and annual grain production growth rate in different periods 19501957 1.69% 1958 19581959 19501990 1214 31 67.39% 17.63% 15 32.61% 14.96% 2.66% 3 3 4 0.7075 19501957196419651978197919901995 1.07% 7.33% 1959196819851994 1.71% 7.11% 60 1966197119 811987 19681985 !-empirenews.page- 4 3 Fig.4 Every three years average of annual cultivated area change rate and annual total grain produotion growth rate 1 1 60 15 1 Table 1 Correlative coefficient of annual cultivated area change rate and annual grain production growth rate in different periods19501957195819601961196819691977197819851986199513.52-6.31-3.18-2.29-2.44-1.92 (P)1.69-2.10-0.40-0.25-0.31-0.1957.45-28.50!-empirenews.page-39.3331.8431.2521.61 (Q)7.18-9.354.923.543.912.16P-Q 0.7639-0.86730.5011-0.67870.61820.26284.2 11 7680kg5445kg 2085kg 1 3.682.611 1hm2 3.68 2.61hm2 1hm2 3.68 2.61hm2 2137 19921994 2 1/3 1/2 2/5 1/5 2.71.81 2 19921994 Table 2 Percentage of different grade of culotivated land their grain yields to the total area andtotal yield respectively during 19921994 in China104hm2104t!-empirenews.page-333522011320214973454281161107945100 (%)30.1048.8028.9033.2041.0018.00100100 11 53 54 80% 50% 21 4.3 6 0.4108hm2 10109t 3.3410!-empirenews.page-5km2 0.991108hm2 0.093108hm2 59.1% 22.9% 0.6% 13.8% 4106hm2 2.67106