【摘要】 1983～1984年,在江苏省吴县用方格法和分层法调查了18年生梅树的叶幕光能分布规律及其影响因素。结果表明,叶幕光能分布直接受叶面积系数、太阳位置和光强的影响。各层叶幕中的光能分布随自然光照的变化而改变,其日平均透光率大小和光照强度日变化范围均从叶幕外围向内膛随累计叶面积系数的增加而递减。叶幕结构直接决定其中的光能分布及其利用效率。生产中,宜通过整形修剪等农业技术措施,维持盛果期梅树高效光合生产的叶幕层厚度1.5m以上、有效叶面积系数5左右。充分提高梅树整个叶幕内光能分布的有效性,对增强树体的光合生产能力有重要的意义。更多还原

【Abstract】 Using grid system and layer methods, factors influencing the light distribution in the canopy of 18-year-old trees of Prunus mume Sieb. et Zucc were studied from 1983 to 1984,in wuxian County, Jiangsu Province. The results showed that the light distribution in the canopy of the trees was directly affected by the intensity and direction of the sunlight as well as the leaf area index ( LAI ) . The light distribution in the different layers of the canopy varied with the changes of the natural sunlight. The mean daily light transmissivity,and the daily changes of the light intensity were reduced as the accumulative total LAI increased from the external to the internal part of the canopy. The light distribution and the efficiency of its utilization were directly determined by the structure of the canopy.In order to enhance the light penetration and its efficiency in phot-osynthesis,it was suggested that by proper, training and pruning and other cultural techniques, the thickness of the canopy of a mature, bearing tree be maintained at more than 1.5m, with an effective leaf area index of appoximately 5 .更多还原