School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, 230009, China.
Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, 230009, China.
Environ Sci Pollut Res Int. 2020 Feb;27(6):6066-6077. doi: 10.1007/s11356-019-07349-3. Epub 2019 Dec 21.
Transient storage has been studied intensively in small streams, but some processes and mechanisms are not yet entirely understood regarding this issue, especially in chronically nutrient-enriched streams. The exploration of transient storage dynamics in nutrient-rich headwater streams has great significance for stream nutrient management in China and other developing countries, which are suffering from eutrophication. In the present study, we conducted five instantaneous slug additions composed of a conservative tracer dissolved with two nonconservative nutrients injections in a suburban small stream (Guanzhen Creek), Lake Chaohu Basin, China. Transient storage metrics were estimated using the model-fitted hydrologic parameters from the one-dimensional transport with inflow and storage (OTIS) model. Regression analyses were performed to examine the relationship between hydraulic parameters and transient storage metrics. Moreover, nitrogen and phosphorus retention efficiency was qualitatively evaluated based on the OTIS model-fitted nutrient parameters. Our results showed that the OTIS model-fitted hydrologic parameters in Guanzhen Creek were within the range of previously published literature. The transient storage metrics of Guanzhen Creek were generally comparable to those in streams with low-to-moderate nutrient levels in other catchments. Moreover, most of the transient storage metrics showed a strong relationship with stream discharge, while only hydrological retention factor showed a markedly negative correlation with flow rate. Given the negative uptake rates for NH-N and SRP in half cases, we reasonably concluded that Guanzhen Creek was hardly incapable of retaining nitrogen and phosphorus.
瞬态储存已在小河流中得到深入研究，但对于这一问题，仍有一些过程和机制尚未完全理解，特别是在长期富营养化的河流中。探索营养丰富的源头溪流中瞬态储存动态对于中国和其他发展中国家的溪流养分管理具有重要意义，这些国家正遭受着富营养化的困扰。本研究在巢湖流域郊区的一条小河流（官镇溪）中进行了五次瞬时推注，包括一个保守示踪剂和两个非保守养分的注入。使用一维水流和储存的模型拟合水文学参数（OTIS）模型来估算瞬态储存指标。进行回归分析以检验水力参数与瞬态储存指标之间的关系。此外，根据 OTIS 模型拟合的养分参数，定性评估了氮和磷的保留效率。结果表明，官镇溪的 OTIS 模型拟合水文学参数在先前发表的文献范围内。官镇溪的瞬态储存指标与其他流域中低到中等营养水平的溪流相当。此外，大多数瞬态储存指标与流量之间存在很强的关系，而仅水力滞留因子与流速呈明显负相关。鉴于在一半情况下 NH-N 和 SRP 的吸收速率为负，我们合理地推断官镇溪几乎无法保留氮和磷。
