SGER: Unpredictable Events of Catastrophic Proportions in Temparate Forest Ecosystems: Developing a Baseline to Assess Cascading Effects and Coupled Interactions

SGER：温带森林生态系统中灾难性比例的不可预测事件：制定评估级联效应和耦合相互作用的基线

• 批准号: 0227608
• 负责人: Emilio Moran
• 金额: $ 2.06万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0227608&HistoricalAwards=false
• 关键词: SGER; Unpredictable; Events; Catastrophic; Proportions

Recently developed ecological theories had identified major disturbance events as crucial factors in large-scale environmental change and evolution. Punctuated equilibrium and chaos theories posit shifts in systems between alternative stable states. Inquiries into the complex dynamics of these relatively abrupt shifts generally have taken place after major disturbances have occurred, with relatively little data available to characterize conditions prior to the events because of their suddenness and unpredictability. Periodic emergence of cicadas in massive numbers are predictable, but they occur infrequently enough to constitute an excellent model of unpredictable disturbance events of catastrophic proportions. This Small Grant for Exploratory Research will establish a set of baseline measurements in central Indiana starting in the summer of 2002 in anticipation of a major cicada outbreak in mid-2004. Cicada outbreaks occur every 17 years in central Indiana, where the size of the outbreak is among the largest found anywhere in the U.S. The time period between outbreaks is so long that most elements of the forest system that the cicadas inhabit effectively have no working memory of the form and character of the outbreak. Before the outbreak, cicadas underground are massive consumption of tree root systems, while after the outbreak, they can rapidly defoliate tree canopies. They become prey to a number of species, frequently inducing "predator saturation" as wildlife gorge on the seemingly endless supply of insects, an eating pattern that can dramatically alter the survival and reproduction rates of those predators during the year of the outbreak and in following years. The laying of eggs can lead to damage or death of affected trees, and loss of tree canopy can alter the microclimatology of the understory and affect transpiration rates, which in turn affects groundwater and surface stream hydrology. In order to develop baseline information against which to evaluate the impacts of the 2004 cicada outbreak in central Indiana, this research team, which includes members drawn from geography, biology, geology, and public and environmental affairs departments, will begin taking a series of measurements in mid-2002. Among variables to be measured are nutrient dynamics, hydrology, canopy cover, tree physiology, seedling establishment, and socioeconomic factors.This award will help establish baseline measurements from which follow-up studies can be conducted in the coming years. In addition to laying the groundwork for a broad range of inquiries into interactions between natural and human systems, the project will have positive broader impacts, including the involvement and training of undergraduate and graduate students and the establishment of databases that can be used for a broad range of inquiries.

最近开发的生态理论将重大干扰事件确定为大规模环境变化和进化中的关键因素。 标点的平衡和混乱理论假定替代稳定状态之间的系统中的变化。 在发生重大干扰后通常发生的这些相对突然转移的复杂动力学的询问，由于事件的突然性和不可预测性，相对较少的数据可用于表征条件。 蝉数量的周期性出现是可以预见的，但很少发生，足以构成灾难性比例的不可预测干扰事件的出色模型。 这项用于探索性研究的小赠款将从2002年夏天开始在印第安纳州中部建立一套基线测量，以期在2004年中期发生大规模的蝉爆。 西卡达爆发每17年发生在印第安纳州中部，那里的疫情大小是美国在美国发现的最大的爆发之一。 在爆发之前，晶木地下是对树根系统的大量消费，而爆发后，它们可以迅速脱落树冠。 它们成为许多物种的猎物，经常在看似无尽的昆虫供应上引起野生动植物峡谷的“捕食者饱和度”，这种饮食模式可以极大地改变这些捕食者在疫情和接下来的几年中这些捕食者的生存和繁殖率。 卵的产卵会导致受影响的树木的损害或死亡，而树冠层的丧失会改变林下的微气候学并影响蒸腾率，这又影响地下水和表面流水文学。 为了开发基线信息，以评估2004年印第安纳州中部的蝉爆的影响，该研究团队包括从地理，生物学，地质学以及公共和环境事务部门中吸引的成员，将在2002年中开始进行一系列测量。 在要衡量的变量中，有营养动态，水文学，冠层覆盖，树木生理学，幼苗建立和社会经济因素。该奖项将有助于建立基线测量值，在未来几年中可以从中进行后续研究。 除了为自然系统和人类系统之间的相互作用进行广泛的询问奠定基础外，该项目还将产生更广泛的影响，包括对本科生和研究生的参与和培训以及可以用于广泛询问的数据库的建立。