CRB: Vole-driven Change in Tallgrass Dominance

ho0129081实验恢复利用土地复垦技术来检验基本的生态理论，从而为管理实践提供信息。这项工作将维持一个现有的草地恢复的例子，以：(1)在足够的时间内监测田鼠驱动的植物优势变化，以区分几种可能的结果；(2)确定直立作物的初始变化是持久的还是短暂的；(3)确定田鼠驱动的效应是否会导致植物丰富度和多样性的持续增加或减少。迄今为止的初步结果提出了以下问题：(1)由田鼠驱动的植物优势变化是否会导致新的单一优势物种的产生？(2)地面生产力的下降是否会持续下去？(3)田鼠驱动的变化会增加还是减少多样性？如果田鼠有效地用令人讨厌的单一大双科草（如Rudbeckia）取代美味的草，群落方面将发生变化，但表观生产力和多样性可能不会发生变化。如果较小的无性系双子代成为共显性，株型将发生变化，立木产量将下降，植物多样性将增加。这些问题的结果对于理解高草群落的起源和维持是有说服力的，因为它们不仅仅是物种相对丰度的增量变化。在实验物种的范围内，它们可能相当于啮齿动物驱动的群落基本特性的变化。这是有蹄类动物对高草群落产生影响的已知和理解的可能性，但啮齿类动物产生类似影响的潜力尚未得到广泛认识。

Howe0129081Experimental restoration uses land reclamation techniques to test fundamental ecological theory and thereby inform management practices. This work will maintain an existing example of a grassland restoration to (1) monitor vole-driven changes in plant dominance over enough time to distinguish among several possible outcomes; (2) determine whether initial changes in standing crop are persistent or transient, and (3) determine whether vole-driven effects produce persistent increases or decreases in plant richness and diversity. Initial results to date raise the following issues: (1) Will the established vole-driven change in plant dominance result in the promotion of a new single dominant species? (2) Will initial reductions in apparent aboveground productivity persist? (3) Will vole-driven changes increase or decrease diversity? If voles effectively replace a palatable grass with a distasteful single large dicot species, such as Rudbeckia, community aspect will change but apparent productivity and diversity may not. If smaller clonal dicots become co-dominants aspect will change, standing crop will decline, and plant diversity may increase. The outcomes of these questions are compelling for understanding the origins and maintenance of tallgrass communities because they would not simply be incremental changes in relative abundance of species. Within the limits of the experimental set of species, they could amount to rodent-driven changes in fundamental properties of the communities. This is a known and understood possibility for ungulate effects on tallgrass communities, but the potential for rodents to have effects of similar magnitude is not widely recognized.