LTREB: Collaborative Research: Hydrologic-nutrient Cycle Interaction in Small, Undisturbed and Human-manipulated Ecosystems

LTREB：合作研究：小型、未受干扰和人为操纵的生态系统中的水文-养分循环相互作用

• 批准号: 9308089
• 负责人: Gene Likens
• 金额: $ 53.5万
• 依托单位: Cary Institute of Ecosystem Studies, Inc.
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-10-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9308089&HistoricalAwards=false
• 关键词: LTREB; Collaborative; Research; Hydrologic; nutrient

In this collaborative project scientists at the Institute of Ecosystem Studies and Syracuse University will continue long-term biogeochemical studies at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire to evaluate trends in atmospheric deposition, streamwater chemistry and cycling of critical nutrient elements. During the past three decades, dramatic changes in atmospheric deposition, streamwater chemistry, vegetation biomass and soil chemistry were observed at the HBEF. These changes have important ecological implications for the management of base-poor forest ecosystems, which are widespread throughout the northeastern U.S. In particular, a decline in atmospheric inputs of base cations has increased the sensitivity of forest and aquatic ecosystems to continuing high inputs of acidic deposition, as well as to forest management practices, such as harvest by clearcutting. Neither the decline in atmospheric inputs nor declines in forest floor concentrations of base cations observed during this period were predicted from existing knowledge or from models of nutrient cycling for forest ecosystems. Significantly, the pattern of recovery following anthropogenic acidification suggests that acidification may not be a fully reversible process. %%% Long-term efforts at synthesis and integration of biogeochemical information at Hubbard Brook will be continued. Results from this research will improve the understanding of biogeochemical flux and cycling in forest ecosystems of the northeastern U.S. In addition, the continuation of the long-term record of precipitation, streamwater and soilwater chemistry at Hubbard Brook will provide a basis for interpreting the effects of changing atmospheric deposition on biogeochemical processes in terrestrial and associated aquatic ecosystems.

在这个合作项目中，生态系统研究所和雪城大学的科学家将在新罕布什尔州的哈伯德布鲁克实验森林（HBEF）继续进行长期生物地球化学研究，以评估大气沉降、河水化学和关键营养元素循环的趋势。 在过去的三十年里，HBEF 观察到了大气沉降、河水化学、植被生物量和土壤化学的巨大变化。 这些变化对贫碱森林生态系统的管理具有重要的生态影响，这种生态系统在美国东北部广泛存在。特别是，大气中碱阳离子输入的减少增加了森林和水生生态系统对持续高酸性沉降输入以及森林管理实践（例如砍伐采伐）的敏感性。 在此期间观察到的大气输入下降和森林地面碱基阳离子浓度下降都不是根据现有知识或森林生态系统养分循环模型预测的。 值得注意的是，人为酸化后的恢复模式表明酸化可能不是一个完全可逆的过程。 %%% 哈伯德布鲁克生物地球化学信息综合和整合的长期努力将继续下去。 这项研究的结果将提高对美国东北部森林生态系统生物地球化学通量和循环的了解。此外，哈伯德布鲁克对降水、河水和土壤水化学的长期记录的持续将为解释大气沉降变化对陆地和相关水生生态系统生物地球化学过程的影响提供基础。