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调查分析了黄土丘陵区5种人工乔灌林小叶杨(Populus simonii)林,山杏(Prunus armeniaca)林,山桃(Prunus davidiana)林,沙棘(Hippophae reamnoides)林,柠条(Caragana korshinskii)林下草本层植物的物种组成、结构特征及其差异。结果表明:5种人工乔灌林下共有37种草本植物,各人工林林下物种组成数量在17~25之间变化,其中以杏树林最多;5种人工林下草本层平均盖度、平均高度、平均生物量存在较大差异,但多样性指数相差不显著。总体来说,黄土丘陵区人工乔灌林下草本植物物种组成较少,物种多样性指数较低,结构参数较小,说明该地区人工林林下环境条件较差,严重影响草本植物个体的生长发育和群落结构。综合分析表明,具有较低林分密度和林冠郁闭度的山杏林是恢复状况相对最好的人工林,揭示了保持合理的林分密度,同时采取疏伐、修枝等管理措施是促进人工林生长发育以及林下草本植物物种多样性和片层结构改善的关键。
Populus simonii forest, Prunus armeniaca forest, Prunus davidiana forest, Hippophae reamnoides forest and Caragana korshinskii forest were studied in the Loess Hilly Region. Species composition, structural characteristics and differences of herbaceous plants. The results showed that there were 37 kinds of herbaceous plants under the artificial alfalfa and shrub-covered forest, and the number of undergrowth species in each plantation varied from 17 to 25, of which apricot forest was the most; average cover of herb layer under 5 kinds of artificial forest, There was a big difference in height and average biomass, but the difference in diversity index was not significant. In general, the herbaceous plants in the loess hilly region had less species composition, lower species diversity index and smaller structural parameters, which indicated that the undergrowth environmental conditions in the artificial plantation in the region were poor, which seriously affected the growth of individual herbaceous plants Development and community structure. The comprehensive analysis shows that the Prunus armeniaca forest with lower stand density and canopy canopy density is the best recovery plantation, which reveals that to maintain a reasonable stand density while taking measures such as thinning and pruning to promote artificial Forest growth and development as well as understory herbaceous plant species diversity and the key to improving the lamellar structure.