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通过对华中神农架海拔1500米至2600米之间11个箭竹样方的研究,阐述了箭竹群落物种丰富度,物种多样性,物种均匀性,生活型谱及群落类型的海拔变化。从最低样方(1680米)到最高样地(2570米),微管束植物从30种降为7种,服从线性模型:Y=55.99-1.83X(R2=0.84,P<0.001);物种多样性从3.18降为1.78,服从线性模型:Y=4.67-0.10X (R2=0.72,P=0.001;物种均匀度在0.83至0.99之间变化,但与海拔并不相关。在生活型谱中,一年生植物,地下芽植物和大高位芽树木的百分比随海拔升高而升高;灌木和中高位芽树木随海拔升高而降低;多年生草本和半灌木与海拔关系不大。箭竹群落可分为5种类型:常绿阔叶林下,落叶阔叶林下,温性针叶林下,寒温性针叶林与混交林下,纯箭竹林。“,”Altitudinal changes in species richness, species diversity, species evenness, life-form spectrum, and community structure of arrow bamboo (Fargesia spathacea) were studied within 11 plots from 1500 m to 2600 m asl on Mount Shennongjia in Central China. From the lowest plot (1680 m) to the highest one (2570 m), vascular plants declined from 30 to 7 species, following a linear model of Y = 55.99 - 1.83X (d.f. = 9, F-value = 48.64, r2 = 0.84, P < 0.001); species diversity reduced from 3.13 to 1.78, following a linear model of Y = 4.67 - 0.10X (d.f. = 9, F-value = 22.82, r2 = 0.72, P = 0.001); species evenness varied from 0.83 to 0.99, but presented little relationship to the altitude (r = 0.112, P = 0.742). In the life-form spectra, with the increase of altitude, the percentage of annual plants (r = 0.60), underground bulb perennials (r = 0.40), and big trees (r = 0.35) tended to increase; shrubs (r = -0.52) and middle-sized trees (r = -0.45) tended to decline; perennial grasses (r = 0.04) and semi-shrubs (r = 0.03) were not strongly related to the altitudinal gradient. Arrow bamboo communities could be classified into five groups: bamboo under evergreen broad-leaved forest, under deciduous broad-leaved forest, under temperate coniferous forest, under cold-temperate coniferous and mixed forest, and pure bamboo community.