DISSERTATION RESEARCH: The Consequences of the Interaction Between Flooding and Drought for Tree Physiology and Diversity in Seasonally Flooded Forests

论文研究：洪水和干旱相互作用对季节性洪水森林中树木生理和多样性的影响

• 批准号: 9902211
• 负责人: Thomas Kursar
• 金额: $ 1.08万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9902211&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Consequences; Interaction; Between

Tropical rainforests experience periods of drought and our studies indicate that rainforest trees, including Prioria copaifera, are drought-sensitive. Tropical forests also are among the most diverse ecosystems on earth and the relative absence of drought may permit greater diversity. These observations led the PIs to propose that the reduced diversity of many tropical forests may be the consequence of periodic drought. The PIs research focuses on P. copaifera, a species that occurs in nearly pure stands in Panama even though the surrounding, nonflooded forest is highly diverse. In an average year, P. copaifera experiences flooding followed by drought. The PIs hypothesize that this is a severely stressful environment for plants and that the dominance by P. copaifera is explained by adaptations permitting it to survive and grow where there is extreme variation in water availability. This hypothesis is consistent with recent proposals that tolerance of flooding, while necessary, may not be sufficient to explain the distributions of plants in flooded habitats. Instead, it is hypothesized that the capacity of a species to respond to drought conditions that follow the end of flooding may also be very important. P. copaifera also is the main tree harvested in Panama and a better understanding of its requirements for establishment will assist in developing a management plan for this species.

热带雨林经历干旱时期，我们的研究表明，包括Prioria copaifera在内的雨林树木对干旱敏感。热带森林也是地球上最多样化的生态系统之一，相对较少的干旱可能使其具有更大的多样性。这些观察结果使PI提出，许多热带森林多样性的减少可能是周期性干旱的结果。PI的研究重点是P.copaifera，这是一种在巴拿马几乎纯林中出现的物种，尽管周围的非淹没森林高度多样化。平均每年，咖啡树都会经历洪水，然后是干旱。PI假设，这是一个严重的压力环境的植物和P. copaifera的优势是通过适应允许它生存和生长的地方有极端变化的水的可用性解释。这一假设是一致的，最近的建议，耐洪水，虽然必要的，可能不足以解释植物在淹没栖息地的分布。相反，据推测，一个物种对洪水结束后的干旱条件作出反应的能力也可能非常重要。P. copaifera也是巴拿马收获的主要树木，更好地了解其建立的要求将有助于制定该物种的管理计划。