提高西藏大于零度年积温3000℃以上农区水热资源利用率探讨

Exploration of the utilization of water and heat resources in the agricultural area having annual accumulated temperature (>0℃) over 3000℃ in Tibet

西藏农区大于零度年积温 ３０００ ℃以上的耕地面积约有 ６～７万公顷，每年只能种一季农作物，尤其是早熟的冬青稞和冬小麦在６月下旬成熟收获，此时才开始雨季， ７、 ８、 ９三个月及 １０月的上半个月的水热资源没有利用。通过几年试验证明，在大于零度年积温３０００度以上的农区耕地进行早熟粮食作物与经济作物套种、复种是可行的，不仅直接提高水、热、耕地资源利用率，提高种植指数，而且调整了农牧业种植结构，可作为用地养地、经济、社会、生态良性循环的新模式，发挥较好的经济、生态、社会效益。

There are about 67 000ha of farmland having annual effective accumulated temperature over 3000℃ in the agricultural area of Tibet, where there is Only one harvest a year, and the main crops are winter highland barley and winter wheat which mature in late June when the rain rain just comes. This means that the water and heat resources in June, July, August and the first half of October are not utilized. Several years experiment demonstrated that it was feasible to intercrop and multiple-crop the face crops with the economic crops in the agricultural area where the annual accumulated temperature (>0℃) are above 3000℃, which either raises the utilization rate of water, heat and cultivated land resources, or adjusts the plantation structure through improving the cropping index. The proposed cultivating systems in this paper might be the new systems forming benign circle among plantation, economic-society and ecology and will play very good economic, ecological and social effects.