太行山中段植物群落优势种生态位研究

Niche of dominant species in the Midst of Taihang Mountain

运用TW INSPAN把样方分为8个群落类型,用Levins、Shannon-wiener生态位宽度公式和Petraitis生态位特定重叠指数公式测定群落中主要种群生态位宽度和生态位重叠,并分析各种群生态位的生态学意义。在总群落中,披针苔草和草地早熟禾的生态位宽度最大,说明它们对群落环境的适应能力最强,对资源的利用能力也最强;在不同的群落里(群落Ⅰ到群落Ⅷ),相同种群生态位宽度有极大差别,草地早熟禾在群落Ⅱ中,B1为2.753,B2为15.561,在群落Ⅷ中,B1为0,B2为1;总群落中,各种群的生态位宽度明显大于其在其他群落里的生态位宽度。两个种群的生态位重叠值越大,说明它们占据越相似的资源空间,珠芽蓼和火绒草的生态位重叠值高达0.892(群落Ⅰ中),说明它们利用资源的相似性程度很高;在总群落中,各种群之间生态位重叠值都很低。

68 quadrats were divided into eight types of communities by TWINSPAN, which can be treated as one-dimension resource states. The niche breadths and overlaps of main dominant species were measured using a series of indices proposed by Levins, Shannon-wiener and Petraitis. Among general communities, Carex lanceolata and Poa pratensis niche breadths value being biggest prove that adaptive capacity to community＇ s environment are the strongest, the ability to use resources is the strongest too. In different communities （community Ⅰ to community Ⅷ）, niche breadths are great difference to the same specie-pairs, Poa pratensis niche breadths in community Ⅱ , B1 is 2. 753, B2 is 15. 561 ; in community Ⅷ, B1 is 0, B2 is 1 ; In the general community, the niche breadths of specie-pairs are obviously greater than in other community. The larger the niche overlap of two species is, the more similarly resource space they occupy, the niche overlap of Leontopodium leontopodioides and Polygonum viviparum amounts to 0.892 （ in the community Ⅰ ）. This proves that they are very similar in utilizing the resources. In the general community, the niche overlaps among species are very low.