LTREB: Long-term Studies of Population and Community Ecology in an Experimentally Fragmented Landscape

LTREB：实验性破碎景观中人口和群落生态学的长期研究

• 批准号: 9308065
• 负责人: Robert Holt
• 金额: $ 30.87万
• 依托单位: University of Kansas Main Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-09-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9308065&HistoricalAwards=false
• 关键词: LTREB; Long; term; Studies; Population

9308065HoltA long-term experiment on habitat fragmentation is underway in the prairie-forest ecotone in eastern Kansas. An archipelago of patches, representing different levels of fragmentation, was arrayed within a period 6 years. During the first six years of the study, fragmentation influenced consumer population dynamics, and the local persistence of herbaceous plant species with clonal life cycles, but did not affect measures of local species richness or the overall rates of succession. It is expected that during the next five, substantial effects of fragmentation upon successional dynamics should begin to appear, because: 1) there is a transition underway from species present in the original seed pool to species colonizing form external source pools, particularly trees and shrubs, and 2) the stature of the dominant plants is increasing, thereby enhancing microenvironmental differences between patch interiors and the surrounding interstitial habitats and hence edge effects. It is also expected that small mammal may be dominant driving factors in woody species establishment, and so fragmentation effects observed in plant succession may be indirect manifestations of fragmentation effects on the small mammal community. This project will document dynamics in plant community composition, local persistence, and plant architecture as a function of the degree of fragmentation, using both ground surveys, canopy analysis technology, aerial photography, and remote sensing. It will also monitor the spatial distributions of small mammals that are potentially important in slowing the invasion of woody species, and to use exclosures to directly measure effects on seedling survivorship. This study is one of the very few experimental studies of habitat fragmentation, and provides a system for exploring more general issue of scale in ecological dynamics.Research projects such as this are fundamental to the better understanding of the associative processes that occur within communities. This understanding will provide a knowledge base on what to expect as landscapes are more finely fragmented. It may also suggest ameliorative measures for maintaining system integrity.

9308065Holta的长期实验在堪萨斯州东部的草原 - 森林生物酮中正在进行中。 在6年的时间内，构成了不同水平的分裂水平的斑块群岛。在研究的前六年中，碎片化影响了消费者人口动态，以及具有克隆生命周期的草本植物物种的局部持久性，但不影响当地物种丰富度或总体继承率的度量。 预计在接下来的五个中，分裂化对继任动力学的实质影响应开始出现，因为：1）从原始种子池中存在的物种到定居的物种发生过渡，构成了外部源池，尤其是树木和灌木，以及2）主要的植物的地位正在增加，从而增强了微环境差异的差异，从而增强了固定互动和周围的固定群体和周围的互联网之间的差异。 还可以预期，小型哺乳动物可能是木质物种建立的主要驱动因素，因此在植物继承中观察到的碎裂作用可能是碎片作用对小型哺乳动物群落的间接表现。 该项目将使用地面调查，冠层分析技术，航空摄影和遥感的植物社区组成，局部持久性和植物结构中的动态作用。 它还将监测小型哺乳动物的空间分布，这些哺乳动物可能在减慢木质物种的侵袭中可能很重要，并使用排他性直接测量对幼苗生存的影响。 这项研究是栖息地分裂的极少数实验研究之一，并提供了一个系统，可以探索生态动力学中更一般的规模问题。诸如此类的研究对于更好地理解社区内发生的关联过程至关重要。 这种理解将为景观的期望提供一个知识基础。 它还可能建议采取改善系统完整性的措施。