松嫩平原西部生长季参考作物蒸散发的敏感性分析

为了预测气候变量扰动引起的区域参考作物蒸散发的变化,该文以松嫩平原西部为研究区,运用FAO Penman-Montieh方程计算了34个站点1951～2001年的生长季参考作物蒸散发,并计算其对气温、风速、日照时数和相对湿度的敏感系数,最后分析了敏感系数的时空变化特征.结果表明:参考作物蒸散发对相对湿度最为敏感,其次是气温,最后是风速和日照时数;5～9月,气温和日照时数的敏感系数呈单峰型分布,在7月份达到最高值,风速敏感系数呈单谷型分布,在7月份达到最低值,相对湿度敏感系数的绝对值表现为持续上升趋势;生长季气候变量敏感系数的空间差异性较大.日照时数、气温、风速等3个气候变量的敏感系数都在研究区西南部形成高值区,而相对湿度则在研究区西南部形成低值区,在研究区东北部形成高值区.

Sensitivity of the reference crop evapotranspiration in growing season in the West Songnen Plain

In order to predict responses of ET0 to perturbation of climate variables, growing seasonal ET0 for 34 meteorological stations in West Songnen Plain from1951 to 2001 was estimated with the FAO-56 Penman-Monteith equation. Sensitivity coefficients of ET0 to air temperature, wind speed, sunshine hours and relative humidity were calculated and their tempo-spatial characteristics were analyzed. The results show that relative humidity is the most sensitive variable to ET0 in general for study area, followed by air temperature, wind speed and sunshine hours. From May to September, the highest sensitivity coefficients to air temperature and sunshine hours is in July, while the lowest sensitivity coefficients to wind speed in July. The absolute sensitivity coefficients to relative humidity increases from May to September. The absolute sensitivity coefficients to all climate variables indicate large spatial variability. The high value area of sensitivity coefficients to air temperature, sunshine hours and wind speed is in the southwest study area, while the low value area of sensitivity coefficients to relative humidity is in the southwest study area with the high value area in the northeast study area.