滴灌核桃不同灌水定额下综合效益优选

为了评估核桃综合效益,以8 a生核桃树为研究对象,通过田间试验,对比了灌水定额为150 m3/hm~2(C1处理)、300 m3/hm~2(C2处理)和450 m3/hm~2(C3处理)的冠层参数,并依托数学分析方法,筛选了果树的最佳灌水定额。结果表明,在核桃果实膨大期,C2处理提高了冠层叶面积指数,而C1、C3处理下透光率、直射光立地系数、散射光立地系数均大于C2处理。核桃生育中期及末期,C2、C3处理明显影响冠层截获的辐射能,但C1处理的作用较弱。随着果实生长,冠层叶面积指数、截获辐射能监测值均不断增大直至平稳,透光率、直射光立地系数、散射光立地系数则不断减小。叶面积指数、灌水定额可以显著影响核桃的最终产量。因此,在滴灌条件下,灌水定额300 m3/hm~2可为核桃的最优生产和最佳经济效益提供有力保障。

Comprehensive Benefit Evaluation of Walnut Trees with Different Irrigation Quota under Drip Irrigation

In order to evaluate the comprehensive benefit of walnut trees,the field test was carried out with 8-year-old walnut trees as the research object.Through the comparison of canopy parameters under 3 levels of irri-gation quota,such as 150 m3/hm2 (C1 treatment),300 m3/hm2 (C2 treatment) and 450 m3/hm2 (C3 treatment) respectively,the best irrigation quota treatment was selected depending on the mathematics analysis method.The results indicated that during the fruit expanding process of walnut trees,C2 had a significant effect on leaf area index.However,the values of light transmittance,DSF and ISF under C1 and C3 treatments were much bigger than C2 treatment.At the middle growth stage and late growth stage,C2 and C3 treatments had obvious effects on radiant energy interception,while C1 treatment had a weak interaction.With the growing of fruits,there was an increase among leaf area index and radiant energy interception,till they were stable.The parameters of light transmittance,direct site factor and indirect site factor decreased continuously.Leaf area index and irrigation quota could significantly influence the production of walnuts.The experiment proved that the irrigation quota of 300 m3/hm2 under drip irrigation could make a strong guarantee for the optimal production and optimum economic benefit.