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近几年来,苏联从不同角度对各种结构护田林,影响农作物产量及其质量问题进行了研究。文章资料,是在克拉斯诺达尔边区刚辛斯基区《劳动》国营农场观测收集的。每块农田大小是900—1000×2230—2240米(205—210公顷)。1950年,在每块农田内按纵向设置了补充护田林带,带间距—500米,高8—10米,宽20米(13行、行间距1.5米),树种:橡树、枔届、皂荚属、桑属、杏、鞑靼槭等。所有林带皆为不透风结构。为获得各种作物产品比较材料,曾采用稀疏方法将3、4号林带改造成稀疏和透风结构。稀疏林带垂直剖面树干间的透风系数32—43%,透风结构为94—96%,而在林冠内的19—28%,林分保护高9—9.5米。综
In recent years, the Soviet Union has studied the various structures of Tian-lin-luhulin, affecting crop yields and their quality issues from different perspectives. The information is collected from the “Labor” state-owned farms in the Kinshasia district of Krasnodar border area. Each farmland is 900-1000 × 2230-2240 meters (205-210 hectares) in size. In 1950, supplements were made in each farmland along the lengthwise direction with a distance of -500 m, height 8-10 m, width 20 m (13 rows, row spacing 1.5 m), tree species: oak, bamboo, Genus, Morus, apricot, Tatar maple and so on. All shelterbelts are air-tight. In order to obtain comparative materials for various crop products, sparse methods were used to transform Nos. 3 and 4 into a sparse and air-permeable structure. The sparse forest belt vertical cross-sectional area between the air permeability coefficient of 32-43%, air-permeable structure of 94-96%, while in the canopy of 19-28%, high stand 9-9.5 meters. Comprehensive