内蒙古7种针茅属植物生态位研究

Study on Niches of 7 Stipa species in Inner Mongolia

针茅属植物是内蒙古草原的主要优势种或建群种,具有重要的经济和生态价值。本研究以内蒙古地区7种针茅属植物为研究对象,分析其在群落中的相对重要值、生态位宽度及其在群落中的生态位重叠。结果表明:短花针茅(Stipa breviflora)、戈壁针茅(S.tianschanica)、小针茅(S.klemenzii)、沙生针茅(S.glareosa)和大针茅(S.grandis)在群落中的相对重要值大于30%,而克氏针茅(S.krylovii.)和贝加尔针茅(S.baicalensis)的相对重要值较小。生态位宽度分析发现:短花针茅、戈壁针茅、小针茅、沙生针茅和大针茅的生态位宽度较高,在群落中具有优势地位,且对生长环境适应能力较强。而克氏针茅和贝加尔针茅生态位宽度显著低于上述5种针茅属植物。贝加尔针茅、克氏针茅、沙生针茅及大针茅的平均生态位重叠指数较大;而戈壁针茅、短花针茅及小针茅的平均生态位重叠指数较小。

Stipa species is a dominant or established species in Inner Mongolia grasslands and has important economic and ecological service functions.In this study,seven Stipa species in Inner Mongolia were studied to analyze their relative importance values,ecological niche breadth and ecological niche overlap effects in the community.The results showed that the relative importance values of S.breviflora,S.tianschanica,S.klemenzii,S.glareosa and S.grandis in the community were greater than 30%,and S.krylovii and S.baicalensis had relatively low importance values.S.breviflora,S.tianschanica,S.klemenzii,S.glareosa and S.grandis had high niche breadth and a dominant position in the community,and were more adaptable to the growing environment.In contrast,the ecotone widths of S.krylovii and S.baicalensis were significantly lower than those of the above five S.species.The average niche overlap indices of S.breviflora,S.tianschanica,S.klemenzii,S.glareosa and S.grandis were relatively greater,and S.breviflora,S.tianschanica and S.klemenzii were smaller.