A Framework to Assess Biogeochemical Response to Ecosystem Disturbance Using Nutrient Partitioning Ratios
A Framework to Assess Biogeochemical Response to Ecosystem Disturbance Using Nutrient Partitioning Ratios
复制标题
使用养分分配比评估生物地球化学对生态系统干扰的响应的框架
作者：
J. Kranabetter;K. McLauchlan;S. Enders;J. Fraterrigo;P. Higuera;J. Morris;E. Rastetter;R. Barnes;B. Buma;D. Gavin;L. Gerhart;L. Gillson;P. Hietz;M. Mack;B. McNeil;S. Perakis
扰动影响到几乎所有的陆地生态系统，但很难确定这些影响的一般原则。为了提高我们对陆地生态系统干扰的长期后果的理解，我们提出了一个概念框架，分析干扰的地球化学影响。我们认为，在成熟的生态系统中，土壤和植物养分储量的比例代表了一个特征性的网站属性。以氮为研究对象，我们假设这种分配比（土壤氮：植物氮）在扰动后会经历一个可预测的轨迹。我们调查的性质，这种分配比与三种方法：（1）营养库存数据在北美森林生态系统，（2）基于过程的生态系统模型，（3）概念转变，在现场养分的可用性与干扰频率的改变。分配比率可适用于各种生态系统和演替状态，从而改善扰动事件的时间尺度。一般短期的经验证据的恢复轨迹的养分储量和分配比表明两个领域的未来研究。首先，我们需要认识到和量化干扰效应如何增加或减少，这取决于它们的净效应是增加还是减少生态系统养分储量。第二，我们需要测试从目前的状态改变干扰频率可能是建设性的或破坏性的影响生态地球化学循环和养分的可用性。对土壤和植被进行反复取样的长期研究，对于进一步发展这一生态地球化学对扰动的反应框架至关重要。
Disturbances affect almost all terrestrial ecosystems, but it has been difficult to identify general principles regarding these influences. To improve our understanding of the long-term consequences of disturbance on terrestrial ecosystems, we present a conceptual framework that analyzes disturbances by their biogeochemical impacts. We posit that the ratio of soil and plant nutrient stocks in mature ecosystems represents a characteristic site property. Focusing on nitrogen (N), we hypothesize that this partitioning ratio (soil N: plant N) will undergo a predictable trajectory after disturbance. We investigate the nature of this partitioning ratio with three approaches: (1) nutrient stock data from forested ecosystems in North America, (2) a process-based ecosystem model, and (3) conceptual shifts in site nutrient availability with altered disturbance frequency. Partitioning ratios could be applied to a variety of ecosystems and successional states, allowing for improved temporal scaling of disturbance events. The generally short-term empirical evidence for recovery trajectories of nutrient stocks and partitioning ratios suggests two areas for future research. First, we need to recognize and quantify how disturbance effects can be accreting or depleting, depending on whether their net effect is to increase or decrease ecosystem nutrient stocks. Second, we need to test how altered disturbance frequencies from the present state may be constructive or destructive in their effects on biogeochemical cycling and nutrient availability. Long-term studies, with repeated sampling of soils and vegetation, will be essential in further developing this framework of biogeochemical response to disturbance.