Changes of China agricultural climate resources under the background of climate change.Ⅶ.Change characteristics of agricultural climate resources in arid and semi-arid region of Tibet Plateau
Based on the 1961-2007 ground observation data from 55 meteorological stations in arid and semi-arid region of Tibetan Plateau, and by using 5-day moving average method and ArcGISIDW module, this paper analyzed the spatiotemporal change characteristics and climatic trend rates of agricultural climate resources in the region in 1961-1980 ( period Ⅰ) and 1981 -2007 ( period Ⅱ) .In 1961-2007, the sunshine duration during the growth season of chimonophilous crops in the study region changed less, while that during the growth season of thermophilic crops increased but with little spatial change.Comparing with those in period Ⅰ, the average value of accumulated temperature in period Ⅱ showed an increasing trend, and the area with ≥1500 ℃ · d during the growth season of thermophilic crops increased by 33.9％.The precipitation decreased gradually from southeast to northwest.During the growth season of chimonophilous crops, the precipitation in the southeast in the two periods reached 800 mm, but the climatic trend in other areas was positive or negative, and the change rate was small.The area with precipitation ≥ 400 mm during the growth season of thermophilic crops in period Ⅱ expanded by 40％ , as compared in period Ⅰ.The reference crop evapotranspiration (ETo ) generally increased slightly, and shared the similar spatial distribution pattern with sunshine duration and accumulated temperature.During the growth season of thermophilic crops, the area with ETo ≥ 400 mm in period Ⅱ expanded by 35.7％ , compared with that in period Ⅰ.In the study period, the heat and precipitation resources during crop growth seasons in Tibet Plateau increased in a certain degree, which was very beneficial to the agriculture-stock production.However, the increase of reference crop evapotranspitation indicated the increase of potential evaporation.Thereby, the researches about the possible effects of climate change on agriculturestock production should be further strengthened.
background of global climate changeTibet Plateauagricultural climate resourcesclimatic trend rate.
国家科技期刊平台
NSTL
万方数据
维普
