Resource Islands: Their Role in the Stability of Desert Ecosystems

资源岛：它们在沙漠生态系统稳定中的作用

• 批准号: 9006621
• 负责人: Ross Virginia
• 金额: $ 36.38万
• 依托单位: San Diego State University Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-10-01 至 1993-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9006621&HistoricalAwards=false
• 关键词: Resource; Islands; Their; Role; Stability

This proposal addresses the role of resource islands in the desertification of the Jornada basin of southern New Mexico. Resource islands represent small-scale patches or "hot spots" of biological activity distributed across a heterogeneous desert landscape. They can be characterized by the functional and structural properties of the shrubs that occupy and form the island, along with the interactions of the shrubs with their immediate abiotic and biotic environment. The significance of these islands to the function and persistence of desert ecosystems in response to disturbances and environmental change is poorly understood. This project, conducted by Drs. Virginia and Reynolds, seeks to understand how desert shrubs acquire resources to form these islands. The investigators are also interested in understanding how the degree of island formation is related to the stability of individual islands, and the role of resource island formation in determining the stability of desert grasslands and shrublands. These tasks will be accomplished by an integrated field and modeling research effort that will: 1) examine the degree of resource island formation associated with the two most successful shrubs (Prosopis glandulosa ımesquite!, Larrea tridentata ıcreosotebush!) in the recently desertified Jornada landscape; 2) determine if structural changes accompanying island formation (e.g. plant architecture) result in a positive feedback system of island self-augmentation; 3) determine if the magnitude and pattern of response of Larrea and Prosopis to an extreme environmental change (e.g. induced summer drought) is a function of the degree of island formation; and 4) develop landscape models that can increase our understanding of the stability of grassland-shrubland systems in a changing environment. Drs. Virginia and Reynolds are leading ecosystem ecologists and have outstanding institutional support for this research.

该提案涉及资源岛在 新墨西哥州南部Jornada盆地的沙漠化。 资源孤岛代表小规模的斑块或“热点”， 分布在异质沙漠中的生物活动 景观 它们的特点是功能和 占据和形成的灌木的结构特性 岛屿，沿着与灌木的相互作用， 直接的非生物和生物环境。 的意义 这些岛屿的功能和沙漠的持久性 生态系统对干扰和环境变化的反应 是很难理解的。 该项目由弗吉尼亚和雷诺兹博士主持，旨在 了解沙漠灌木是如何获取资源形成这些 群岛 调查人员也有兴趣了解 岛屿形成的程度如何与 个别岛屿，以及资源岛屿形成的作用， 决定沙漠草原和灌木丛的稳定性。 这些任务将由一个综合外地办事处完成， 建模研究工作将：1）检查 资源岛的形成与两个最成功的 灌木（Prosopis glandulosa <$mesquite！，三齿海鲶 <$creosotebush！）在最近荒漠化的Jornada景观; 2） 确定伴随岛屿形成的结构变化 (e.g.工厂结构）导致正反馈系统， 岛屿自我增强; 3）确定是否规模和 Larrea和Prosopis的反应模式极端 环境变化（如夏季干旱）是一个函数 岛屿形成的程度;以及4）发展景观 模型，可以增加我们对稳定性的理解 变化环境中的草地-灌木林系统。 弗吉尼亚博士和雷诺兹博士是生态系统生态学家 并为这项研究提供了出色的机构支持。