DISSERTATION RESEARCH: Leaf litter leachate and the fate of phosphorus in seasonal lowland tropical forests

论文研究：季节性低地热带森林中的落叶渗滤液和磷的归宿

• 批准号: 0909734
• 负责人: Michelle Mack
• 金额: $ 1.34万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0909734&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Leaf; litter; leachate

Phosphorus is a key element for plant growth, so phosphorus availability in the soil is critical for world food production and carbon cycling by terrestrial ecosystems. Yet the controls on phosphorus cycling are not well understood, and these controls are expected to change with global climate change and continued land-use conversion. Understanding phosphorus cycling in the lowland tropics is especially critical because many soils of this region have mineral constituents that greatly hinder the mobility of this nutrient. The goal of this study is to improve our understanding of how leaf litter leachate (water extracts of senesced leaves) affects phosphorus cycling in seasonal lowland tropical forests. This study will evaluate whether leaf litter leachate is important for the return of nutrients to the soil, and if leaching potential can be predicted from structural and chemical characteristics of litter. The researchers will also investigate the extent to which litter leachate controls phosphorus cycling within the plant-soil-microbe environment. The broader impacts of this research include its contribution to our understanding of the relationships between litter leaching and rainfall patterns, and the applications of these results for predicting and mitigating the effects of climate change. An improved understanding of how natural systems cycle phosphorus could also have applications for improving production in managed systems, without high inputs of fertilizer. During the course of this research, the student will mentor undergraduate students through coursework hosted by the Smithsonian Tropical Research Institute in Panama, and by engaging University of Florida undergraduates in this research.

磷是植物生长的关键元素，因此土壤中磷的可用性对于世界粮食生产和陆地生态系统的碳循环至关重要。然而，对磷循环的控制措施尚不清楚，而且这些控制措施预计会随着全球气候变化和持续的土地利用转变而改变。了解低地热带地区的磷循环尤其重要，因为该地区的许多土壤含有矿物质成分，极大地阻碍了这种养分的流动。这项研究的目的是提高我们对落叶渗滤液（衰老叶子的水提取物）如何影响季节性低地热带森林中磷循环的了解。这项研究将评估落叶渗滤液对于养分返回土壤是否重要，以及是否可以根据凋落物的结构和化学特征来预测渗滤潜力。研究人员还将调查垃圾渗滤液在植物-土壤-微生物环境中控制磷循环的程度。这项研究的更广泛影响包括它有助于我们理解凋落物淋滤和降雨模式之间的关系，以及将这些结果应用于预测和减轻气候变化的影响。更好地了解自然系统如何循环磷也可以应用于提高管理系统的产量，而无需大量肥料投入。在这项研究过程中，该学生将通过巴拿马史密森尼热带研究所主办的课程来指导本科生，并让佛罗里达大学的本科生参与这项研究。