SGER: Comparative Demography of Desert Plants Following El Nino

SGER：厄尔尼诺现象后沙漠植物的比较人口学

• 批准号: 9810414
• 负责人: Thomas Ebert
• 金额: $ 2.3万
• 依托单位: San Diego State University Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-15 至 2000-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9810414&HistoricalAwards=false
• 关键词: SGER; Comparative; Demography; Desert; Plants

Abstract 9810414 Ebert Understanding why natural landscapes look as they do requires understanding how vegetation responds to unusual events. In the desert of southern California, rain typically is confined to winter months; occasionally, however, unusual late summer storms sweep up from the south. During the past 25 years there have been two of these unusual summer events: Hurricane Kathleen in 1976 and Hurricane Nora in 1997. In response to these events, seeds germinated for species that usually do not have new additions to their populations. Germination of seeds is just the first step in adding new plants to a population; they also must survive. The winter following Hurricane Kathleen was relative dry and seedling mortality was high. The winter of 1997-98 is during an El Nino and is proving to be much wetter. Seed germination following an unusual summer hurricane followed by high winter rains associated with an El Nino may prove to be the most important event of this century for many plant species in the desert. Our study of seedling growth and survival will help to understand the importance of rare events in ecosystems.

摘要9810414埃伯特 要理解自然景观为什么看起来像这样，就需要理解植被如何对不寻常的事件做出反应。 在加州南部的沙漠中，降雨通常只限于冬季的几个月;然而，偶尔也会有不寻常的夏末风暴从南部席卷而来。在过去的25年里，有两次这样不寻常的夏季事件：1976年的飓风凯瑟琳和1997年的飓风诺拉。 作为对这些事件的回应，种子发芽的物种通常不会有新的增加到他们的人口。 种子的发芽只是向种群中添加新植物的第一步;它们也必须存活下来。 凯瑟琳飓风过后的冬天相对干燥，幼苗死亡率很高。 1997-98年的冬天是在厄尔尼诺现象期间，事实证明要潮湿得多。 一场不寻常的夏季飓风之后的种子发芽，紧接着是与厄尔尼诺现象有关的冬季大雨，这可能是本世纪沙漠中许多植物物种最重要的事件。 我们对幼苗生长和存活的研究将有助于理解生态系统中罕见事件的重要性。