CRB: Mechanisms of Persistence in Tallgrass Prairie Forbs: An Experimental Approach Coupled with a Retrospective Analysis of Long-term Patterns

大多数植物群落由许多不同的生长形式组成，其中一种通常在生物量中占主导地位。生态学研究倾向于关注优势生长形式和物种，主要是因为它们处理流经系统的大部分能量。然而，当考虑物种丰富度时，通常是从属生长形式中的物种对多样性贡献最大。除了原始物种外，人们对从属物种，特别是长寿的多年生植物在群落中维持自身的机制知之甚少。全面评估这些不常见物种的持续机制对于维持自然和恢复群落的多样性至关重要。本研究将对康扎草原研究自然区高草类牧草（非木本多年生草本植物）的持续生长机制进行实验研究。该地点的主要特征是两种生长形式（优势草和草本），这有助于比较优势和次要生长形式之间的资源利用和对火、放牧、光照和氮的反应。这些植物具有许多生活史特征，并将其在高草基质中的持久性归因于已建立的个体/无性系的长停留时间。描述性研究和涉及水、氮和光操作的全因子实验相结合，将用于阐明长寿的forbs在地形和火灾历史变化的“草海”中保持存在的过程。

Most plant communities are comprised of many different growth forms with one that usually dominates in biomass. Ecological studies tend to focus on the dominant growth form and species, primarily because they process most of the energy that flows through the system. However, when species richness is considered, it is usually species within the subordinate growth forms that contribute most to diversity. With the exception of ruderal species, relatively little is known about the mechanisms by which subordinate species, especially long-lived perennials, maintain themselves in communities. A comprehensive evaluation of the mechanisms of persistence of these less common species is critical to maintaining diversity within natural and restored communities. This study will experimentally examine the mechanisms of persistence of tallgrass prairies forbs (non-woody, perennial herbs) at the Konza Prairie Research Natural Area. This site is characterized primarily by just two growth forms (the dominant grasses and forbs) and this facilitates comparisons of resource use and responses to fire, grazing, light regime, and nitrogen between dominant and subordinate growth forms. The forbs share many life history characteristics and owe their persistence within the tallgrass matrix to the long residence times of established individuals/clones. A combination of descriptive studies and a full factorial experiment involving water, N and light manipulations will be used to elucidate the processes by which long-lived forbs maintain their presence in a "sea of grass" that varies topographically and in fire history.