1963—2012年新疆棉花需水量时空分布特征

Spatial and temporal distribution of water requirement of cotton in Xinjiang from 1963 to 2012

研究基于新疆地区54个国家基本气象站1963—2012年的逐日气象资料,采用联合国粮食与农业组织FAO推荐的Penman-Monteith公式及作物系数法,计算了近50年来新疆棉花全育期和各生长阶段需水量。并利用线性趋势估计、MK检验、空间插值法对农作物全育期及各生长阶段需水量年际变化趋势和空间分布特征进行分析。结果表明:1)1963—2012年,新疆54个气象站棉花全育期平均需水量为759 mm,各站变化范围为555—1205 mm,差异明显。其空间分布整体呈现西北向东南递增、南疆大于北疆、东部大于西部的趋势。2)1963—2012年,在棉花的生长初期与发育期,全疆需水量空间分布总体由北向南增大并呈带状。在棉花的生长中期与生长末期,需水量空间分布表现为由西向东增大的格局。3)近50年棉花不同生长阶段需水量总体呈现下降趋势,并且除了生长中期下降趋势较显著外其他都不太明显。其中,生长中期下降速率最大为6.1 mm/10a,发育期及生长末期下降速率次之分别为2 mm/10a和1.3 mm/10a,生长初期下降速率最小,需水量以0.6 mm/10a的速率递减。4)新疆1963—2012年棉花全育期需水量总体呈下降趋势,递减速率平均约为5.3 mm/10a,并在1981年开始发生突变。5)全育期年需水量下降倾向率总体呈现与全育期平均需水量相同的空间分布特征,总体呈现北疆小于南疆、东部大于西部、由西北向东南递增的空间分布特征。

Using the daily meteorological data from 54 stations in Xinjiang from 1963 to 2012, the water requirements of cotton （WRC） during the whole growing period and at different growth stages were calculated based on the FAO Penman- Monteith model and crop coefficient method. In addition, we used the methods of linear regression, Mann-Kendall test, and inverse distance weighting to analyze the spatio-temporal changes in WRC in Xinjiang in the last 50 years. The results show the following ： 1 ） The average WRC during the whole growing period in Xinxiang was 759 mm. The values of WRC obtained from 54 meteorological stations in Xinxiang ranged between 555 mm and 1205 mm. The overall spatial distribution of WRC in Xinxiang varied obviously. The WRC in the south-east, south, and east was greater than that in the north-west, north, and west, respectively. 2） The WRC during the early growth and developmental stages of cotton in Xinxiang from 1963 to 2012 was assumed to be zonal and increased from north to south. During the middle and end growth stage, the WRC in the east was greater than that in the west. 3 ） The WRC at different growth stages showed a decreasing trend in the past 50 years, with the middle growth stage showing a more obvious downward trend. The greatest decline of 6.1 mm/10 years was observed in the middle grcwth stage, followed by 2 mm/10 years during the developmental stage and 1.3 mm/10 years in the end growth stage. The smallest decline of 0.6 mm/10 years was detected in the initial stage, d） The WRC of the whole growing period in Xinxiang was overall reduced from 1963 to 2012. The average mutation of decline in XirLxiang began in 1981. （ 5 ） The spatial distribution of requirement was similar to the average water requirement during the whole growing of water requirement in Xinxiang was ascending from north-west to south-east decline was 5.26 the decline in the period. Generally, mm/10 years and the average annual water the spatial distribution