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灌草丛是分布在秦岭——淮河之间各个省山地丘陵上森林破坏后的一种主要植被型。灌草丛群落的区系组成包括9—31种植物,优势种为草类并混有灌木。影响形成这种群落的主要因素是土壤含水量。它在地上部分生物量的鲜重平均为102.7公斤/亩,载畜量平均为25.38亩/羊/年。在发育良好的灌草丛下,土壤侵蚀模数为2700吨/平方公里;当植物群落受到破坏时可增高到8,640吨/平方公里。在立地条件良好且进行封山育林时,则灌木生长较高并占优势,同时长有落叶阔叶幼树。如果加以保护,灌草丛就可能演替为森林。如果将灌草丛作为放牧地,其结果是不仅生产力低而且造成水土流失。由于它能控制水土流失并改善环境,因此在利用灌草丛时要十分重视从生态学观点来考虑。
Shrubs and shrubs are a major vegetation type distributed in the mountainous hills of all provinces between the Qinling and Huaihe rivers. The fauna assemblages of shrub-grass communities include 9-31 species of plants, dominated by grasses and mixed with shrubs. The main factor affecting the formation of this community is the soil moisture content. The average fresh weight of above-ground biomass was 102.7 kg / mu and the average carrying capacity was 25.38 mu / sheep / year. Under well-developed shrubs, the soil erosion modulus is 2,700 tons per square kilometer, which can be increased to 8,640 tons per square kilometer when plant communities are damaged. When the site is in good condition and closing hillsides to facilitate afforestation, the shrubs grow higher and predominate, and there are deciduous broad-leaved saplings at the same time. If protected, shrubs may succeed in the forest. If shrub grass is used as grazing land, the result is not only low productivity but also soil erosion. Because of its ability to control soil erosion and improve the environment, great care should be taken from the ecological point of view when using shrubs.