草坪杂草生态位研究

调查研究草坪杂草的重要值、生态位宽度、以及不同种类杂草之间的生态位重叠值 ,能够揭示杂草种间生态相似关系 ,能够预测杂草之间相互影响的趋势。利用杂草种间的相互制约关系 ,可以指导合理地使用除草剂 ,从而达到降低草坪养护成本 ,保护环境的双重效果。以武汉市区多种不同种类草坪为研究对象 ,对该地区草坪主要杂草进行了系统调查 ,通过七级目测法 ,计算了草坪 2 0种主要杂草的重要值 ,并计测了它们的生态位宽度和生态位重叠值。结果表明 ,看麦娘 (Alopecurusaequalis) ,牛蘩缕(Stellaria media) ,野燕麦 (Avena fatua) ,猪殃殃 (Galium aparine) ,一年蓬 (Erigeron annuus) ,鼠麴草 (Gnaphalium multiceps) ,毛茛 (Ranunculus arevensis) ,通泉草 (Mazus japonicus)等杂草的实际生态位比较宽 ,它们是本地区草坪的主要杂草。而猪殃殃(Galium aparine) ,婆婆纳 (Veronica persica) ,野燕麦 (Avena fatua)等杂草间的生态位重叠值大。杂草生态位宽度大小反映了杂草利用资源的多样化水平或特化水平 ,通常生态位宽度大的杂草以牺牲对局域范围内资源的利用效率来换取对大范围内资源的利用能力

Researches on weed niche in turf

Niche is an important theoretic problem in studying plant population and community ecology. Niche breadth may be a measure of turfs' using diversity to environmental resource and it is a response of weeds to ecological niche. Niche-overlap is a measure to display the similarity of plant interspecies bionomics. Studies on the important value, niche breadth, and niche overlap of different weeds in turf can reveal the ecological demand similarity of different weeds, and can forecast the trend of reciprocal affect between different kings of weeds. So it can give some guide in using herbicide reasonably and get to a double-aim of dropping cost in maintaining turf and protecting the environment. When turf is identified as a healthy ecosystem, this turf ecosystem remains resistant or resilient to the long-term and unexpected disturbance caused by natural or human activities. Long-term application of a certain herbicide let a variation of weed populations in turf. It increases the difficulty controlling weeds effectively. Therefore, it is a hot problem for us to solve. In this paper, different kinds of turfs in Wuhan region were exemplified systematically. In the turfs in Wuhan region, 20 sites under different ecological condition were surveyed in detail with seven scales by visua- lization of weed dominance to rape to obtain the important value of 20 main weeds. The species niche breadth and niche overlap were calculated on the basis of the investigation. The results show that Alopecurus aequalis (0.559), Stellaria media (0.4341), Avena fatua (0.3214), Gnaphalium multiceps (0.2909), Galium apaine (0.2747), Ranunculus arvensis (0.2686), and Mazus japonicus (Thunb) O. Ltze (0.2474) have bigger value in ecological niche. The bigger value of the weeds showed that they have wider ecological-amplitude, and they can adapt to more kinds of environment. Because different weeds have different ecological annidation, they have different niche overlap value. The more ecological niche overlaps value show that the more same ecological resource can be used, and they must compete more fierily. Different weeds can be classfied according to their overlap value. For example, Galium apaine, Avena fatua, and Veronica persica belong to the same class. Galium apaine and Veronica persica have a bigger overlap value than Avena fatua. Alopecurus aequalis, Stellaria media, Mazus japonicus (Thunb) O. Ltze., Gnaphalium multiceps, Cardamine hirsuta L., Ranunculus arvensis and Poa annual can be classed together. These weeds always occur in similar spaces and have a large number. As compared with those of the other species, the niche overlaps between Galium apaine, Veronica persica, and Avena fatua were higher. The bigger value of weeds showed that they have wider ecological-amplitude, and they can adapt to more kinds of environment.Niche breadth reflects weeds' variety or specialization level in using nature resource. In the ordinary way weeds having a bigger niche breadth immolate the using-efficiency to the resource in a small range, and gain the using capacity to the resource in a bigger range. When the resource is insufficient, weeds used vary resource have stronger ecological accommodation, bigger distribution range and more living chance. Because different weeds have varied ecological annidation, they have different niche overlap value between each other. The more ecological niche overlaps value show that the more same ecological resource can be used, and they must compete more fierily. Different weeds can be classified according to their overlap value, and these weeds always occur in similar spaces and have a large number.