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虽然对风障保护下大豆冠丛形态学变化已经有了报道,但这种变化怎样影响着冠丛的光照特征却鲜为人知,而这对于了解林带保护下大豆的增产机制、生长模式以及大豆的产量是十分必要的。本文主要研究了风障林对大豆冠丛形态结构,冠丛光照,大豆的生长和产量的影响。供试品种为“Wayne”,于1978～1979年的生长季节中种植在内布拉斯加州、米德、内布拉斯加大学农场的风障林带保护区和空旷区,土壤为粉沙粘壤土。和空旷区相比,保护区内生长着的大豆上部的叶面积密度、叶片密度、叶片大小都较小,这种较小的冠丛有利于光合有效辐射的穿透。风障可以降低风速,减小蒸发,即使在土壤有效水分较小的情况下,保护区内的水分状况也很好。良好的水分状况和光照条件,将使保护区内生长着的大豆的产量有明显提高,每株荚数,每荚粒数以及收获指数也会增加。因为大豆产量受冠丛光的穿透量的限制,所以栽培品种的选择应根据这种形态学变化才能使大豆增产。大豆生长予测模型也应考虑这种变化。植物群落对太阳辐射的有效利用取决于它对光的截获量、光在冠丛的分布和单叶光合速率。冠丛结构决定着光的截获和光的分布,因此,冠丛结构是决定作物产量的一个重要因子。一般冠丛最上部比较稠密,大部分光都被截获在这一层,穿透到下层的光受到了限制。试验表明,在大豆冠丛下部人为地增加光照可以明显地提高大豆产量。有报道说:在风障林带保护下,大豆会发生一些形态学变化,但这种变化又是怎样影响冠丛光照的尚未有人评价,这对进一步了解林带保护下大豆增产的生理机制是十分必要的。本文的目的就是为了研究林带对大豆冠丛形态学,冠丛光照、大豆的生长和产量的影响。
Although the morphological changes of soybean pods under wind protection have been reported, how this change affects the light characteristics of the crown plexus is poorly understood. This is very important for understanding the soybean yield-increasing mechanism, growth pattern and soybean The production is very necessary. This paper mainly studied the effects of wind-sheltered forest on the morphology and structure of crown and clump of shrub, the growth and yield of soybean. The test variety “Wayne” was planted in the windbreak shelter and open area of the farm of University of Nebraska, Mead, Nebraska during the growing season of 1978-1979. The soil was silt sand Loam Compared with the open area, the leaf area density, leaf density and leaf size in the upper part of the soybean growing in the reserve are smaller, and this smaller crown bundle is conducive to the penetration of photosynthetically active radiation. Wind barriers reduce wind speed and reduce evaporation, and the water conditions in protected areas are good, even with less effective soil moisture. Good water conditions and light conditions will significantly increase the yield of soybeans growing in protected areas. The number of pods per plant, the number of grains per pod and the harvest index will also increase. Because soybean yield is limited by the amount of crown plexus penetration, the selection of cultivars should be based on this morphological change to increase soybean yield. Soybean growth prediction model should also consider this change. The effective use of plant community for solar radiation depends on its interception of light, the distribution of light in the crown plexus and the leaf photosynthetic rate. The structure of the crown plexus determines the interception of light and the light distribution. Therefore, the crown plexus structure is an important factor that determines crop yield. The crown is generally densely populated with most of the light trapped in this layer, limiting the light penetration into the lower layer. Experiments show that artificially increasing the light in the lower part of the soybean crown can significantly increase soybean yield. It has been reported that there are some morphological changes in soybean under the protection of windbreak shelterbelts, but how this change has affected the light of crown clumps has not been evaluated yet, which is necessary to further understand the physiological mechanism of soybean yield increase under belt protection of. The purpose of this paper is to study the effect of forest belt on the morphology of crown shrubs, crown shrubs, soybean growth and yield.