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土壤有效水分和土壤结构影响细垂穗草(Bouteloua gracilis)和野牛草(Buchloe dacty-loides)的相对分布,然而当两种植物共同生长时,养分梯度也会影响到二者的相互竞争作用,还会影响弃耕地植被的恢复。我们做温室实验试图验证在养分相对充足及贫瘠条件下,两种植物间的竞争效应。在4种高低浓度有效N、P组合的养分条件下,细垂穗草和野牛草分别以不同的种内、种间组合配对方式栽植,种间竞争仅在有效N和P浓度高的条件下显著。细垂穗草在混播时比单播地上部分生物量增大,分蘖数量提高,N、P含量增高;而相同条件下,野牛草的分蘖数量减少,地下部分P含量下降。野牛草匍匐茎产量仅在P浓度高的条件下最大。无论何种养分处理条件,细垂穗草的生物量均大于野牛草。在有效养分浓度高时,细垂穗草的竞争力大于野牛草;而在养分浓度低时,细垂穗草的抗逆性比野牛草强。
The soil available water and soil structure affect the relative distribution of Bouteloua gracilis and Buchloe dactyloides, however, when the two plants grow together, the nutrient gradient also affects their mutual competition, Will also affect the restoration of abandoned vegetation. We did a greenhouse experiment trying to verify the competition effect between the two plants under relatively nutrient-rich and barren conditions. In the four kinds of high and low concentrations of available N, P combination of nutrient conditions, the fine weeping grass and the Picrosis respectively in different species, interspecific combination of planting, interspecific competition only in the conditions of high concentrations of N and P Significant. In the mixed sowing, the biomass of fine weeds increased more than that of uniccended, the tiller number increased and the contents of N and P increased. Under the same conditions, the number of tillering decreased and the content of P in underground part decreased. Buffalo grass stolon yield only in the highest P concentration. No matter what kind of nutrient treatment conditions, the biomass of fine-drooping grass is greater than that of bison grass. When the effective nutrient concentration is high, the thin-headed grass is more competitive than the wild grass, while in the low nutrient concentration, the thin-headed grass is more resistant than the bison grass.