黄羊滩沙地人工林林下植物多样性的研究

Study on plant diversity of plantation in Huangyangtan sand-land

生物多样性是人类共同的财富,是引导人工林经营过程中必须考虑的因素。正确评价沙地林下植物的多样性,对黄羊滩沙地的沙化恢复具有重要的意义。为此,以地处张家口市宣化县的黄羊滩沙地人工林为研究对象,采用标准地调查法和样方调查法,运用丰富度指数(D)、多样性指数(H)、均匀度指数(E)进行数据分析,结果表明:飞蓬、胡枝子、狗尾草3种植物出现的几率最大,而黄羊滩地区共有植物92科288属527种。对3个多样性指数的分析结果显示,物种数较多的1号样地的杨树、刺槐混交林的物种数和多样性指数都是最高的,其中物种数达到17种,均匀度指数为2.087 8、多样性指数为0.872 4、丰富度指数为3.384 5,而8号样地的沙柳地物种只有狗尾草1种,而均匀度指数、多样性指数、丰富度指数都为0。由此看出:黄羊滩人工林下草本层的植物多样性还很低,而混交林林下草本层的物种数较多,各个多样性指数也较高,应大量营造混交林,包括针阔混交林、阔阔混交林,以提高黄羊滩沙地人工林稳定性和物种多样性。

Biological diversity as the common wealth of mankind ,is a factor that must be con-sidered in the process of guiding the plantation management .Proper evaluation of understory sand-land plant diversity has important significance to recover the sand-land desertification of Huangyangtan .In this paper ,the sand-land plantation in Huangyangtan located in Xuanhua was studied ,using standard ground survey and quadrat method ,with statistic data analyzed based on the richness index （D） ,diversity index （H） ,and evenness index （E） .Survey find-ings showed that in the 16 standard plots （S1 -S16 ） there are total 31 kinds of plants , belonging to 15 families ,mainly in Leguminosae ,Asteraceae ,and Poaceae .The three plant species with the highest emergence ratio are Erigeron acer ,Lespedezabicolor ,Setaria viri-dis in the area of Huangyangtan with plants belonging to 92 families ,288 genera and 527 species .The analysis by the three plants species diversity indices showed a larger number （17） of plant species and higher species diversity indexes （E=2 .087 8 ,H=0 .872 4 ,D=3.384 5）in S1 of poplar-locust mixed forest ,while S8 of Salix psammophila has only Setaria viridis . with zero species diversity indexes （E=0 ,H=0 ,D=0） .This shows there remains very low plant diversity under Huangyangtan plantations ,therefore ,native species are supposed to be introduced to improve the species diversity of plantations ,to build a more suitable type of plantation grown in the Huangyangtan sand-land ,and thereby ,to accelerate the recovery of sand-land ecosystem .