Assessment of tree nutrition and identification of key factors/processes affecting its spatial and temporal variation in eastern Canadian forests

评估加拿大东部森林的树木营养并确定影响其时空变化的关键因素/过程

• 批准号: 41725-2011
• 负责人: Côté, Benoit
• 金额: $ 1.97万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=521568
• 关键词: Assessment; tree; nutrition; identification; key

High levels of acidic atmospheric deposition for many decades have had some significant negative impacts on the soil environment on many sites in eastern Canada. As a result, the mineral nutrition of some species is becoming marginally sufficient for good growth and acid soil tolerant species are gaining dominance. Soil acidification can affect soil fertility in two ways: 1. by decreasing the availability of some nutrients primarily through soil leaching and 2. by increasing the solubility of some metals that can reach toxic levels in some soil horizons. The formation of toxic layers of soil could force nutrient demanding and acid sensitive species to restrict their rooting to soil horizons less affected by soil acidification, and in the process, exacerbate the effect of reduced nutrient availability.

几十年来，高水平的酸性大气沉积对加拿大东部许多地点的土壤环境产生了一些重大的负面影响。结果，一些物种的矿质营养已不足以维持良好的生长，耐酸性土壤的物种正在获得优势。土壤酸化可以通过两种方式影响土壤肥力：主要通过土壤淋滤和土壤淋滤来降低某些养分的有效性。通过增加某些金属的溶解度，这些金属可以在某些土壤层中达到有毒水平。土壤有毒层的形成会迫使养分需要型和酸敏感型物种将其生根限制在受土壤酸化影响较小的土层，并在此过程中加剧养分有效性降低的影响。