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以河北片麻岩山区退耕地核桃(Juglans Regia)×苜蓿(Medicago sativa)模式为研究对象,采用挖掘取样法,研究了果草复合系统早期细根根系密度的空间分布特征,并比较分析了单作和间作模式下核桃细根分布的差异。结果表明:间作模式下核桃细根根系在垂直方向和水平方向上均呈现“低高低”的二次多项式分布,集中分布于20~60cm(垂直)、10~80cm(水平);苜蓿细根在垂直方向和水平方向上分布分别呈现负指数型和指数型分布,集中于0~30cm(垂直)、110~150cm(水平);在垂直深度0~20cm和水平距离100~150cm范围内,苜蓿核桃相对重叠比大于1,苜蓿根系占据主导地位,核桃根系则在较深垂直空间和较近林带具有明显优势;与核桃单作模式相比,果草间作模式下核桃细根从量上有所减少,在垂直方向上分布变深,在水平方向上亦有所下降。核桃苜蓿间作模式下细根分布具有一定的交织区域,存在竞争。
Taking the Juglans Regia × Medicago sativa cultivated land in Hebei Gum Ma Mountain as study object, the spatial distribution characteristics of root exponential density in early stage of fruit-grass composite system were studied by using digging-sampling method. Differences in the Fine Root Distribution of Walnut under and Intercropping. The results showed that in the intercropping mode, the root exudates of walnut showed quadratic polynomial distribution of “low high” and low low high in both vertical and horizontal directions, which were concentrated in the range of 20-60 cm (vertical) and 10-80 cm (horizontal) The distributions of roots in the vertical and horizontal directions show negative exponential and exponential distributions, respectively, and are concentrated at 0-30 cm (vertical) and 110-150 cm (horizontal). At the vertical depth of 0-20 cm and the horizontal distance of 100-150 cm, Alfalfa walnut relative overlap ratio is greater than 1, alfalfa root dominance, walnut root system in the deeper vertical space and the near forest belt has obvious advantages; compared with walnut monoculture mode, Decreased, the distribution in the vertical direction becomes deeper, and also decreased in the horizontal direction. The fine root distribution in walnut alfalfa intercropping has a certain interweaved area, there is competition.