黄山微毛樱群落主要种群生态位特征

Niche characteristics of dominant population of Cerasus clarofolia community in Huangshan Mountain

利用Levins、Hurlbert生态位宽度公式和Horn生态位重叠公式,测定了黄山微毛樱群落13种重要乔木和16种主要灌木种群的生态位宽度和生态位重叠。结果表明:乔木层中,微毛樱和白檀生态位宽度较大,Bi(Levins生态宽度)和Ba(Hurlbert生态位宽度)分别为0.942、0.884和0.939、0.730,而黄山松和小叶白辛树等的生态位宽度较小;生态位重叠值小于0.5的种对有47对,占总数的60.3%;生态位重叠值大于0.5的种对有28对,占总数的35.9%;不发生重叠的种对有3对。灌木层中,白檀的幼树、伞八仙和华空木为优势种,其Bi和Ba分别为0.872、0.862,0.799、0.742和0.689、0.587,而鸡桑、锐齿臭樱和棣棠的生态位宽度较小;生态位重叠值小于0.5的种对有67对,占总数的55.8%;生态位重叠值大于0.5的种对有48对,占总数的40.0%;不发生重叠的种对有5对。具有较大生态位宽度的树种是微毛樱群落的主要优势种或伴生种,对群落小气候具有广泛的适应性。具有相似生境要求或相似生物学特征的物种间生态位重叠较大,生态位宽度较窄的物种间也可能存在较大的生态位重叠。

The niche breadths and overlaps of 13 dominant populations in tree layer and 16 dominant populations in shrub layer of Cerasus clarofolia community in Huangshan Mountain scenic areas were measured using the formulas de-scribed by Levins, Hurlbert and Horn. The results showed that in the tree layer, niche breadths of C.clarofolia and Sym-plocos paniculata were broader than other species, with Levins( Bi ) and Hurlbert?s ( Ba ) values being 0.942, 0.884 and 0.939, 0.730, respectively, but that of Quercus stewardii, Pinus taiwanensis and Pterostyrax corymbosus were narrower. Forty-seven species counterparts, accounting for 60.3% of the total, had niche overlap values smaller than 0.5;twenty-eight species counterparts, accounting for 35.9%, had niche overlap values larger than 0.5, and 3 species counterparts had no niche overlap. In shrub layer, young tree of S. paniculata, Hydrangea angustipetala and Stephanandra chinensis had broder niche breadths, and their Bi and Ba values were 0.872, 0.862, 0.799, 0.742 and 0.689, 0.587, respective-ly, while Morus australis, Maddenia incisoserrata and Kerria japonica had narrower niche breadths. Sixty-seven species counterparts, accounting for 55.8% of the total, had niche overlap values smaller than 0.5;Forty-eight species counter-parts, accounting for 40.0%, had niche overlap values larger than 0.5, and 5 species counterparts had no niche overlap. Those species with broader niche breadths were dominant or accompanying species, and had high adaptability to commu-nity microclimate characteristics. The niche overlaps among the species with the same or similar environment requirements and similar biological properties were greater, and it is possible for the species with narrower niche breadths to overlap more.