农林复合生态系统防护林结构对植物生物多样性的影响

文章以拜泉县三道镇久胜村的4块样地为例,从物种丰富度指数、多样性指数、生物量等方面研究了漫岗丘陵区不同防护林结构对林下植物生物多样性的影响。结果表明,不同结构之间物种丰富度存在很大差异,6种结构13个样点物种丰富度指数平均值为0.038,其中结构V(27年落叶松)物种丰富度指数最大,为平均值的4.4倍;结构Ⅲ(5年落叶松+5年樟子松)中5年樟子松林下植物物种丰富度指数最小,仅为平均值的16%。通过Shannon-Wiener多样性指数的计算,得出杨树林下的植物生物多样性不如灌木和松树林下的植物生物多样性高。就树木生物量而言,南北向的杨树带生物量均比东西向的大,但两地块之间南北向的杨树带生物量和东西向树带相差无几。

Effects of windbreak belt structure in agroforestry on plant biodiversity

By using four sample fields in Jiusheng village, Sandao town and Baiquan county, the paper studied the effects of different windbreak belt structures in hummock and hill district on biodiversity by means of the index, such as species richness, diversity index and biomass. The results showed that there was great difference among species richness in different structures. The average species richness of 6 structures, 13 sample dots was 0.038. The species richness index of structure V(Larix spp. of 27 years old) was the biggest as 4.4 times as average level. The smallest was the species richness index of plants under Pinus sylvestris var. of 5 years old in structure Ⅲ(Larix spp. of 5 years old + Pinus sylvestris var. of 5 years old), as 16% as average level. By Shannon-Wiener biodiversity index we get the conclusions that the biodiversity of poplar belts is smaller than that of shrub belts and pine belts. Otherwise, as the biomass of trees as been concerned, the research reveales that biomass of the poplar belts in the south-north rows is bigger than that in the west-east rows but the biomass of trees has no differences between the south-north rows and the west-east rows while they are located between two fields.