滇东北作物耗水特性及影响因素

Characteristics and influencing factors of crop water requirements in northeastern Yunnan

基于滇东北地区3个气象站点(会泽站、昭通站、沾益站)1955—2013年逐日气象资料,采用FAO-56 Penman-Monteith公式,计算并分析滇东北地区水稻、春玉米和冬小麦全生育期需水量及其变化趋势,同时采用偏相关分析和逐步回归分析探讨各气象因子对主要粮食作物需水量影响的程度.结果表明:昭通站主要粮食作物需水量随时间呈不同程度减少,每10 a水稻需水量减少10.07 mm,春玉米减少1.44 mm,冬小麦减少1.06 mm.而其他站点呈增加趋势,水稻需水量每10 a分别增加8.85,4.48 mm,春玉米分别增加8.38,4.57 mm,冬小麦分别增加7.39,3.10 mm.3个站点同一种作物各生育阶段需水量规律基本一致,水稻各生育期需水量从大到小依次为:分蘖,拔节,抽穗,乳熟,黄熟,返青;玉米的依次为:拔节,灌浆,苗期,孕穗,成熟;小麦的依次为:乳熟,开花,成熟,苗期.日照和平均风速是影响水稻和玉米需水量最主要的气象因子,且呈显著正相关关系,就各站点而言,影响冬小麦需水量的气象因子存在差异,其中会泽站和沾益站同日照时数和平均气温呈显著正相关,而昭通站与平均湿度呈显著负相关,同日照时数呈显著正相关关系.

Based on daily meteorological data from three typical meteorological stations( Huize,Zhaotong and Zhanyi stations) during 1955—2013,rice,spring maize and winter wheat water requirements were calculated by FAO- 56 Penman- Monteith equation and their changing trends were analyzed;simultaneously the influence of meteorological factors on main crops water requirements were probed by partial correlation and stepwise regression analysis. The results show that at Zhaotong station,the main crops water requirements decrease in various degree with the time. An decreasing tendency of rice,spring maize and winter wheat is 10. 07 mm /10 a,1. 44 mm /10 a and 1. 06 mm /10 a,respectively.However,the main crops water requirements at other stations show an increasing trend. Rice water requirements at Huize and Zhanyi stations are increased by 8. 85 mm /10 a and 4. 48 mm /10 a,respec-tively; spring maize water requirements are increased by 8. 38 mm /10 a and 4. 57 mm /10 a,respectively; winter wheat water requirements are increased by 7. 39 mm /10 a and 3. 10 mm /10 a,respectively. Moreover,the water requirements of the same crop during different growth stages at the three stations are similar. The decreasing order of rice water requirements at every growth stage is tillering >jointing > earing > milk > yellow maturity > turning green; for spring maize the decreasing order is jointing > grouting > seeding > booting > maturity; for winter wheat the decreasing order is milk > flowering >maturity > seeding. The influences of different meteorological factors on crop water requirements are different. Sunshine and mean wind speed are main factors,which have a significant positive correlation with rice and spring maize water requirements. The climatic factors which affect winter wheat water requirements are different for every station. The winter wheat water requirements at Huize and Zhanyi stations have a significantly positive correlation with mean temperature and sunshine hours,while those at Zhaotong station have a significant positive correlation with sunshine hours,but a significant negative correlation with relative humidity.