title: [Changes of China agricultural climate resources under the background of climate change. I. Spatiotemporal change characteristics of agricultural climate resources in South China].
abstract: By using the 1961-2007 daily weather data from 66 meteorological stations all over South China, this paper studied the spatiotemporal change characteristics of agricultural climate resources, including heat, light, and precipitation, in this region on the scales of whole year and temperature-defined growth season. In 1961-2007, the mean annual air temperature in this region tended to be increased by 0.20 degrees C x (10 a)(-1), and the climatic trend of > or = 10 degrees C accumulated temperature in temperature-defined growth season increased gradually from north to south, with an average of 98 degrees C x d x (10 a)(-1). Comparied with those in 1961-1980, the areas of the accumulated temperature zone of 6200-7500 degrees C x d and 7500-8000 degrees C x d in 1981-2007 increased by 1.5 x 10(4) and 4.7 x 10(4) km2, respectively. In 1961-2007, the sunshine hours on the scales of whole year and temperature-defined growth season decreased by -57 h x (10 a)(-1) and -38 h x (10 a)(-1), respectively, and the areas with sunshine hour > or = 1800 h on the two scales tended to be decreased, compared with those in 1961-1980. The precipitation on the two scales increased slightly, and the increment varied obviously in different parts of the region. There were 62% and 52% of the stations where the reference crop evapotranspiration on the scales of whole year and temperature-defined growth season was in negative, respectively. In 1981-2007, the high-value area of reference crop evapotranspiration decreased, while the low-value area increased, compared with those in 1961-1980. The mean climatic trend of annual humidity index was 0.01 x (10 a)(-1), and 70% of the stations showed an increasing trend. Comparing with that in 1961-1980, the humidity index on the scale of temperature-defined growth season in 1981-2007 was increased by 0. 02, with 53% of the stations showed positive. On the whole, the change characteristics of climate in South China in 1961-2007 showed a tendency of warming and wetting, which would impact the cropping system, yield, and agricultural structure in the region.
authors.affiliation: College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.forename: Xiao-guang
authors.initials: XG
authors.lastname: Yang
authors.forename: Wen-feng
authors.initials: WF
authors.lastname: Wang
authors.forename: Zhi-juan
authors.initials: ZJ
authors.lastname: Liu
mesh_terms: D002681:China; D057231:Climate Change / Q000706:statistics & numerical data*; D018556:Crops, Agricultural / Q000254:growth & development*; D004463:Ecology / Q000379:methods; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D011891:Rain; D013472:Sunlight; D013696:Temperature