LTREB: Sustainability of Soil Fertility in Model Tropical Ecosystems

LTREB：热带生态系统模型中土壤肥力的可持续性

• 批准号: 9975235
• 负责人: Donald Stone
• 金额: $ 40万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-15 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9975235&HistoricalAwards=false
• 关键词: LTREB; Sustainability; Soil; Fertility; Model

9975235HartshornMaintenance of soil fertility is a major challenge to forest restoration and sustainable development in the humid tropics, where organic matter breaks down quickly, weathering of mineral matter is fast, and high rainfall leaches nutrients essential for plant growth. Among the many factors that control soil fertility, two are of great importance in both natural and managed ecosystems, the number of plant life forms and the frequency with which the plant community is harvested or disturbed. Replicated plantations comprising three fast-growing tropical tree species established in 1991 at La Selva Biological Station in Costa Rica are used to study the controls that these two factors exert on soil fertility. In some plantations, the trees are grown in monocultures, which are harvested and replanted at three different intervals. Other plantations contain the trees plus plants of two other life forms, a palm and a banana-like herb. Research for the next five years on this LTREB project will address five broad objectives: (1) determine nutrient retention, loss, and recovery following stand turnover, (2) attempt soil recuperation through nutrient replacement, (3) quantify processes that account for changes in soil fertility as a function of changes in community structure, (4) track the sequential changes in interspecific interactions and their impact on soil fertility, and (5) identify mechanisms involved in temporal changes in complementary resources use. The project will provide valuable insight on tropical forest ecology and management. In addition, the project will continue to train undergraduates and graduate students, and serve as a laboratory for courses offered by the Organization of Tropical Studies, local and international universities, and informal science visits.

9975235 Hartshorn保持土壤肥力是森林恢复和可持续发展的一个主要挑战，在潮湿的热带地区，有机物分解迅速，矿物质风化快，高降雨量浸出植物生长所必需的营养物质。在控制土壤肥力的许多因素中，有两个在自然和管理的生态系统中非常重要，即植物生命形式的数量和植物群落被收获或干扰的频率。复制的人工林，包括三个快速增长的热带树种于1991年建立在拉塞尔瓦生物站在哥斯达黎加的研究控制，这两个因素对土壤肥力的影响。在一些种植园中，树木以单一栽培方式生长，在三个不同的时间间隔收获和重新种植。其他种植园包括树木和其他两种生命形式的植物，棕榈和香蕉状草本植物。未来五年，LTREB项目的研究将实现五个主要目标：（1）确定林分周转后养分的保持、损失和恢复，（2）通过养分置换尝试土壤恢复，（3）将土壤肥力的变化过程量化为群落结构变化的函数，（4）跟踪种间相互作用的顺序变化及其对土壤肥力的影响，以及（5）识别涉及补充资源使用的时间变化的机制。该项目将提供有关热带森林生态和管理的宝贵见解。此外，该项目将继续培训本科生和研究生，并作为热带研究组织、当地和国际大学提供的课程和非正式科学访问的实验室。