Metabolic scaling of stream dissolved oxygen across the U.S. Atlantic Coast
Metabolic scaling of stream dissolved oxygen across the U.S. Atlantic Coast
复制标题
美国大西洋沿岸河流溶解氧的代谢规模
DOI：
10.1016/j.scitotenv.2022.153292
复制
发表时间：
2022
影响因子：
9.8
通讯作者：
Abdul-Aziz, Omar I.
中科院分区：
文献类型：
--
作者：
Ahmed, Shakil;Abdul-Aziz, Omar I.
我们采用流体力学和水利工程的量纲分析方法，研究了美国大西洋沿岸河流中出现的“生物地球化学”相似性（参数化简）和溶解氧（DO）的标度假设。发现了两个具有机械意义的无量纲数，即流“代谢”数和“DO饱和”数的分数。“代谢”数代表了各种气候、水文、生物化学和生态驱动因素（如水温、大气压、河流宽度和深度、总磷、pH和盐度）对河流DO的协同控制。对“代谢”与“DO饱和度”数据的图形探索导致1998-2015年不同沿海河流的数据崩溃成一个紧急过程图，表明三种代谢状态（高、过渡和低）。高代谢和低代谢状态分别表现为对水体DO消耗最有利和最不利的环境条件——通过减少溶解和再作用，以及增加有机分解、呼吸和硝化作用。紧急过程图得出了“DO饱和”数作为“代谢”数函数的广义幂律标度关系（指数~ 1/3；Nash-Sutcliffe效率，NSE = 0.83-0.85）。利用代谢标度定律建立了一个广义经验模型，成功预测了美国大西洋沿岸不同河流的DO （NSE = 0.83）。突现过程图、代谢标度规律和DO预测模型将有助于了解和管理美国和其他地区沿海溪流的水质和生态系统健康。
We investigated the hypothesis of emergent ‘biogeochemical’ similitude (parametric reduction) and scaling of dissolved oxygen (DO) in coastal streams across the U.S. Atlantic Coast by employing dimensional analysis methodology from fluid mechanics and hydraulic engineering. Two mechanistically meaningful dimensionless numbers were discovered as the stream ‘metabolic’ number and the fraction of ‘DO saturation’ number. The ‘metabolic’ number represented the synergistic control on stream DO from various climatic, hydrologic, biochemical, and ecological drivers (e.g., water temperature, atmospheric pressure, stream width and depth, total phosphorus, pH, and salinity). A graphical exploration of the ‘metabolic’ versus the ‘DO saturation’ numbers led to collapse of data during 1998–2015 from diverse coastal streams into an emergent process diagram, indicating three metabolism regimes (high, transitional, and low). The high and low metabolism regimes were, respectively, characterized by the most and least favorable environmental conditions for stream DO depletion—through reduced dissolution and reaeration, as well as increased organic decomposition, respiration, and nitrification. The emergent process diagram led to a generalized power law scaling relationship of the ‘DO saturation’ number as a function of the ‘metabolic’ number (exponent ~ 1/3; Nash-Sutcliffe Efficiency, NSE = 0.83–0.85). The metabolic scaling law was leveraged to develop a generalized empirical model to successfully predict DO in diverse streams across the U.S. Atlantic Coast (NSE = 0.83). The emergent process diagram, metabolic scaling law, and prediction model of DO would help understand and manage water quality and ecosystem health of coastal streams in the U.S. and elsewhere.