DISSERTATION RESEARCH: Elucidating the Roles of Abiotic and Biotic Factors in Exotic Species Establishment: A Trait-based Approach

论文研究：阐明非生物和生物因素在外来物种建立中的作用：基于性状的方法

• 批准号: 1502071
• 负责人: Priyanga Amarasekare
• 金额: $ 2万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1502071&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Elucidating; Roles; Abiotic; DISSERTATION; RESEARCH; Elucidating; Roles; Abiotic

Invasions of non-native species are one of the greatest environmental challenges of the 21st century, threatening not only native flora, fauna, and the ecosystem services that they provide, but also agriculture, human health, and the economy. Invasion and establishment of non-native species is driven by both physical (abiotic) factors, such as temperature, and by interactions with native species (biotic factors), such as predation and competition. Understanding how these biotic and abiotic factors magnify or cancel one another is necessary for forecasting the conditions under which invasive species establish in new localities, and for developing methods to control the spread of such species. Yet, most studies overlook the joint effects of abiotic and biotic factors on invasion success because they examine on only one type of factor. This project addresses this problem by examining the joint effect of environmental temperature and competition for resources on invasion by an insect in California. The research combines laboratory experiments, field observations, and mathematical models to forecast the conditions that allow the invasive species to spread. Currently, the U.S. spends hundreds of millions of dollars annually on invasive species control. This project aims to reduce this cost by providing the scientific knowledge needed to develop more cost-effective control measures.The project integrates manipulative experiments, field observations and mathematical models to examine how temperature and competition impact population dynamics and species interactions of an ecologically related pair of insects, one native and one invasive. The impetus for this work comes from a native-invasive interaction occurring in the California coastal sage scrub community in which two Hemipterans (Family: Pentatomidae), native Murgantia histrionica and recent North American invasive Bagrada hilaris, compete for their primary host, the perennial shrub Cleome isomeris. This study aims to (i) quantify the joint effect of temperature and density on life history traits (fecundity, development, mortality) of the two species, and (ii) parameterize a mathematical model of stage-structured population dynamics that incorporates mechanistic descriptions of vital rate temperature responses, and time-dependent developmental delays that arise due to temperature variation. These goals are achieved through (i) a fully factorial lab experiment with density and temperature treatments, (ii) estimation of model parameters using maximum likelihood methods applied to experimental data, which are used to analyze a delay differential equation model of population dynamics, and (iii) field collection of insect abundances to test the model's predictions.

非本地物种的入侵是21世纪最大的环境挑战之一，不仅威胁着他们提供的本地动植物，动植物和生态系统服务，而且威胁着农业，人类健康和经济。非本地物种的入侵和建立是由温度（例如温度）以及与本地物种（生物因子）（例如捕食和竞争）相互作用的驱动的。对于预测入侵物种在新地区建立的条件以及开发控制这种物种传播的方法，了解这些生物和非生物因素如何放大或取消彼此是必要的。然而，大多数研究忽略了非生物和生物因素对入侵成功的关节影响，因为它们仅检查一种类型的因素。该项目通过检查环境温度和资源对加利福尼亚昆虫入侵的共同影响来解决这一问题。该研究结合了实验室实验，现场观测和数学模型，以预测允许入侵物种传播的条件。目前，美国每年花费数亿美元用于入侵物种控制。该项目旨在通过提供制定更具成本效益的控制措施所需的科学知识来降低这一成本。该项目整合了操纵实验，现场观察和数学模型，以研究温度和竞争如何影响人口动态和物种相关的昆虫，一种原生和一种侵入性。这项工作的动力来自加利福尼亚沿海鼠尾草灌木社区发生的本地侵入性互动，其中两个半伴侣（家庭：五特这科），原住民穆尔甘蒂亚·希特里昂卡（Murgantia Histrionica）和最近的北美入侵性巴格拉达·希拉利斯（Bagrada Hilaris）争夺了他们的主要宿主，多年生的苏里氏菌群异构体。这项研究的目的是（i）量化温度和密度对两种物种的生命历史特征（繁殖，发育，死亡率）的关节作用，以及（ii）参数化阶段结构化种群动力学的数学模型，该模型融合了由于温度变化而引起的重要温度温度响应的机理描述。这些目标是通过（i）使用密度和温度处理的完全阶乘实验室实验来实现的，（ii）使用应用于实验数据的最大似然方法估算模型参数，该方法用于分析人口动态的延迟微分方程模型，以及（iii）昆虫丰富度的现场收集以测试模型的预测。