--- --- 40 1992.3
10 69 9 11 or 11
Dry farming
571 567 11 10 500 10 174
1972 50 1 100 2 10
1970 1994 1997 211
9 8
B.C.361 338
5 7
1000 500 500
3 1963 1250 2500 100 1986
1200
1998 1978 2001 40 1996 11 1997 Vol34No2 1251999 11 2001 11 The Great Wall
2
50 70
199711 5 2003 20 2000 51 2002 1965
00 1966 1981 1984 40 4 1983 81 11 1975 3 1998
14 1999 1998