Mechanisms Controlling Metal and Phosphorus Dynamics in an Experimentally Acidified Watershed in Maine

缅因州实验酸化流域中金属和磷动力学的控制机制

• 批准号: 0414144
• 负责人: Ivan Fernandez
• 金额: --
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-15 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0414144&HistoricalAwards=false
• 关键词: Mechanisms; Controlling; Metal; Phosphorus; Dynamics

The Bear Brook Watershed in Maine (BBWM) is a long-term (14+ years), whole-watershed experiment designed to study ecosystem responses to acid deposition. One watershed has been treated bimonthly by helicopter with nitrogen and sulfur since 1989. Results have documented progressive acidification of soils and streams, substantial losses of soil nutrients (e.g., calcium), increased nitrogen cycling, and changes in tree foliar chemistry. Little research has been done on phosphorus, a critical nutrient in ecosystems. This project will evaluate the effects of long-term watershed acidification on metal mobilization (focusing on aluminum and iron) and linked effects on phosphorus at BBWM by studying soils, soil solutions, stream water, and biota (e.g., foliage, roots, and soil microorganisms).Policy makers have focused on emissions regulations to control nitrogen and sulfur due to known ecological effects on forests and streams such as acidification, nitrogen saturation, and base cation depletion. Little is known about how these ecological changes will, in turn, affect phosphorus cycling. Understanding changes in this key nutrient may be pivotal to understanding underlying mechanisms of forest decline and surface water quality, and will therefore be fundamental to policy and management planning.

缅因州（BBWM）的熊溪流域是一项长期（14岁以上）的全球实验，旨在研究生态系统对酸性沉积的反应。 自1989年以来，直升机用直升机用直升机进行了两流域治疗。结果证明了土壤和溪流的进行性酸化，土壤养分的大量损失（例如，钙），氮气循环增加，以及树叶化学的变化。 几乎没有研究磷，这是生态系统中一种关键的养分。 该项目将通过研究土壤，土壤解决方案，溪流水和生物群（例如，叶子，根和根部和土壤微生物的群体对固定剂的群体影响，对糖类的影响范围构成群体，通过研究土壤解决方案，水流和生物群来评估长期分水岭对金属动员（侧重于铝和铁）的影响以及对BBWM磷的影响。以及酸化，氮饱和度和碱阳离子耗竭等流。 关于这些生态变化将如何影响磷循环的知识知之甚少。 了解这种关键营养素的变化对于理解森林衰落和地表水质的潜在机制可能是关键的，因此对政策和管理计划至关重要。