松嫩平原碱化草甸天然翅碱蓬种群的密度制约模型

 翅碱蓬是一年生藜科植物，耐碱性极强。本文根据在单—种群落随机取样的调查数据，从种群水平分析了松嫩平原碱化草甸天然翅碱蓬种群的密度制约特征。结果表明，翅碱蓬种群在不同生长期及不同数量性状的密度制约模型均可由多种函数形式同时较好地表达出来。但本文仅以相关性最好的拟合方程作为种群某一性状密度制约特征的模型。孕蕾期的平均植株重和单位面积籽实重的密度制约表现为变形双曲线函数y=a+b/x形式；籽实成熟期的平均植株重、平均植株籽实重、平均植株种子数和单位面积种子数均表现为幂函数y=ax-b形式；地上生物量在孕蕾期为变形双曲线函数y=1/(a+bx)形式，在籽实成熟期为对数函数y=a-blnx形式。

THE MODELS ON DENSITY DEPENDENCE TO NATURAL SUAEDA HETEROPTERA POPULATION OF ALKALIZATION MEADOW IN THE SONGNEN PLAIN OF CHINA

Suaeda heteroptera is an annual herb of Chenopodieceae which is the most tolerant to alkali. According to the investigated data of random sampling in single species community, density dependence of the characters of natural S.heteroptera population alkalization meadow in the Songnen Plain of China we- re analysed. The results showed that the models of density dependence in di- fferent growth stages and on different quantitative characters of the population could be more presented by many functional forms. But in this paper, the model of density dependence of a certain attribute of the population were represented by the best correlation equation among the functions. The density dependence of the population showed that function form was the hyperbola function y=a b/x for both mean weight per plant in the booting stage and fruits weight per unit area; that the power function y=ax~(-b) was for mea weight per plant in the ripening stage, mean weight of fruits per plant, mean number of seeds per plant and seeds number per unit area; and that the hyperbola function y=1/(a bx) is appropriate for above-ground biomass of the population in the booting stage and the logarithmic function y=a-b ln x in the ripening stage.