澳大利亚参考作物蒸散量变化及影响因素分析

摘要

[Objective] To discuss regional response of reference evapotranspiration (ET0) to global climate change and its influencing factors. [Method] Penman-Monteith equation was adopted to calculate ET0 in Australia from 1998 to 2007. Spatiotemporal change characteristics were analyzed by using GIS spatial analysis tools and relationships between ET0 and main climate factors were also analyzed. [Results] The results showed that multi-year average ET0 increased from the east and south part to the northwest part and inland, and its distribution was consistent with climate zones. Multi-year average ET0 of the whole region was 1 750 mm, obtaining minimum and maximum values in 2000 and 2002 respectively. Regional ET0 decreased in the order of summer, spring, autumn and winter; January and December got the highest monthly ET0, while June got the lowest value 79.55 mm. ET0 positively correlated with mean temperature and solar radiation, R2 for each were 0.83 and 0.94, while the relationship between ET0 and average relative humidity was negative, and precipitation had no significant relationship with ET0. [Conclusion] This research could provide important reference for crop water requirement study and making irrigation method for Australia.%[目的] 探讨参考作物蒸散量在全球气候变化环境中的区域响应形式及其影响因素.[方法] 利用Penman-Monteith方程计算澳大利亚1998～2007年的参考作物蒸散量(ET0),通过GIS方法分析ET0的时空变化特征并探讨了ET0与主要气候因子的关系.[结果] ①澳大利亚多年平均ET0呈半环状分布,自东、南两面向西北部和内陆逐渐增加,与气候带分布具有较高的空间一致性;②全区平均ET0约1 750 mm,2000年取得最小值(1 647.97 mm),2002年取得最大值(1 851.45 mm);③ ET0按夏、春、秋、冬的顺序递减,1月、12月ET0最高,分别为200.42 mm、201.24 mm,6月最低,为79.55 mm;④ ET0与平均气温、太阳辐射量正相关,确定性系数分别为0.83、0.94,与平均相对湿度呈负相关关系,与降水量没有明显的相关性.[结论] 该研究为澳大利亚的作物需水量研究及灌溉措施的制定提供了参考.