上海市郊早春杂草的生态位计测

Determination on Niche of Early Spring Weeds in Shanghai Suburb

野外调查了上海市郊261个样地早春杂草的生态重要值,共计出现106种杂草,计测了其中84种主要杂草的生态位宽度和生态位重叠值。以生态位重叠值为指标,采用主坐标排序法(principal axis analysis,PAA)对84种主要杂草的生态位重叠关系进行了二维排序,并分析了主要杂草与伴生种的生态位重叠关系。结果表明:1)生态位最宽的前10种杂草分别为猪殃殃Galium aparine(0.442)、加拿大一枝黄花Solidago Canadensis(0.341)、刺果毛茛Ranunculus muricatus(0.336)、野胡萝卜Daucus carota(0.300)、大巢菜Vicia sativa(0.297)、泽漆Euphorbia beliocopia(0.297)、荠菜Capsella bursa-pastoris(0.292)、野塘蒿Conyza bonarinisis(0.278)、波斯婆婆纳Veronica persica(0.256)、葎草Humulus scandens(0.236);2)与主要杂草猪殃殃生态需求相似的种类主要有波斯婆婆纳、葎草、加拿大一枝黄花、刺果毛茛等,与重要外来杂草加拿大一枝黄花生态相似的主要有春一年蓬、葎草、猪殃殃等,刺果毛茛的主要伴生杂草有野老鹳草、棒头草Polypogon fugax、泥胡菜Hemistepta lyrata等;3)根据生态位重叠关系,84种主要杂草大致可以分为湿生、旱生和草坪杂草3种生态类型。

The importance values of early spring weeds were surveyed at 261 sites of different habitats in Shanghai suburb, a total of 106 weed species were recorded from these sites; the niche breadths and the niche overlaps of 84 main weeds with their emergence frequency exceeding 5% were calculated in the paper. Based on their overlaps, the two-dimensional ordination plot of 84 main weeds was drawn using the method of principal axis analysis. Additionally,the ecological similarity of the other weeds with the main weeds was discussed according as their niche overlaps. The results show that Galium aparine （0.442）,Solidago canadensis （0.341） ,Ranunculus murieatus （0.336） ,Daucus carota（0.300）, Vicia sativa（0.297） ,Euphorbia beliocopia（0.297） ,Capsella bursapastoris （0.292） ,Conyza bonarinisis （0.278）, Veronica persica（0.256） ,Humulus scandens （0.236）are the first ten weeds having the bigger niche breadths than any other, the main company weeds of Galium aparine are Veronicapersica ,Humulus scandens,Galium apar/ne, those of Solidago Canadensis are Erigeron philade lphicus.Humulus scandens ,Galium aparine, for Ranunculus muricatus, its main company weeds are Geranium carolinianum,Polypogonfugax,Hemistepta lyrata. Based on their niche overlaps,three ecological types of weeds in the area could be classified：dry weeds, wet weeds and weeds in turf.