Table 3. Site characteristics of long-term fertilization experiments at six typical croplands in China.
| Site | Coordinate | Altitude (m) | MAT (°C) | EAT (°C) | MAP | MAE | Climatic zone in China | Cropping system | Experiment Initiation |
|---|---|---|---|---|---|---|---|---|---|
| HH | 50°15'11″N 127°27'07″E | 180 | −1.5 | 2180 | 510 | 650 | Mild-Temperate, Semi-Humid | Mono-cropping Wheat or Soybean | 1979 |
| GZL | 43°30'23″N 124°48'34″E | 220 | 4.5 | 1700 | 589 | 1400 | Mild-Temperate, Semi-Humid | Mono-cropping Maize | 1990 |
| HS | 37°44'00″N 115°47'00″E | 28 | 13.0 | 4889 | 550 | 1300 | Warm-Temperate, Semi-Humid | Double-cropping Wheat-maize | 1981 |
| ZZ | 35°50'00″N 113°42'00″E | 59 | 14.5 | 2661 | 615 | 1450 | Warm-Temperate, Semi-Humid | Double-cropping Wheat-maize | 1990 |
| YL | 34°17'51″N 108°00'48″E | 524 | 13.0 | 2323 | 575 | 993 | Warm-Temperate, Semi-Humid | Double-cropping Wheat-maize | 1990 |
| QY | 26°45'00″N 111°52'00″E | 120 | 18.5 | 3429 | 1255 | 1470 | Sub-Tropical, Humid | Double-cropping Wheat-maize | 1990 |
HH: Heihe in Heilongjiang province; GZL: Gongzhuling in Jilin province; HS: Hengshui in Hebei province;
ZZ: Zhengzhou in Henan province; YL: Yanglin in Shanxi province; QY: Qiyang in Henan province.
MAT: mean annual temperature; EAT: effective annual temperature;
MAP: mean annual precipitation; MAE: mean annual evaporation.