世界谷物产量与农业气候资源利用效率

THE CEREAL YIELD IN THE WORLD AND THE UTILIZATION EFFICIENCY OF AGROCLIMATIC RESOURCES

世界谷物产量的农业气候资源利用效率有明显地区差异。谷物产量的综合气候资源利用效率以欧洲最高，为２．７８，其后依次是北美洲１．４３，大洋洲１．４３，亚洲１．４０，南美洲１．１２，非洲最低，为０．６１。相对光能利用率（％）从０．０３（安哥拉）至０．７６（荷兰），热量利用效率（ｋｇ／１℃·ｈａ）从０．０３至２．０３（荷兰、瑞典），降水量利用效率（ｋｇ／·ｈａ）从０．３５（安哥拉）至８．７１（荷兰）（表１－４）。光热、降水量与作物要求的条件配合较一致的地区，谷物转换效率高。干旱、半干旱地区水分容易发挥效率。世界农业气候资源谷物利用潜力很大。中国比高产国家利用效率低主要是单产利用效率低，应以提高单产的资源利用效率为重点。

There are obvious regional differences in the utilization efficiency of agroclimatic resources for the cereals yield in the world. The comprehensive utilization efficiency for the cereal yield in Europe is the greatest,which is 2. 78. Next it is 1.43 in North America and Oceania, 1.40 in Asia, and 1.12 in South America.In Africa it is the lowest, which is only 0. 61. The relative light energy utilization efficiency (%) is from 0. 03 (in Angola) to 0. 76(in Netherland). The Heat utilization efficiency (kg.℃-. ha-) is from 0. 03 to 2. 03 (in Netherland and Sweden). The precipitation utilization efficiency (kg. mm-1. ha-1 )is from 0. 35 (in Angola) to 8. 71 (in Netherland). The transfer efficiency of cereals is high in regions where the conditions of light,heat and precipitation cooperate relatively well with the crop demand (see Table 1-4). On the other hand,the moisture is easy to exert efficiency in dry and Semi-dry regions.Therefore the potential utilization efficiency of agroclimatic resources in the world is very great. In China,the utilization efficiency of agroclimatic resources is lowrer than that in countries with high yield mainly because of the low utilization efficiency of the unit area preduction. So to rise the utilization efficiency of agroclimatic resources of the unit area preduction will become an important task in the future.