Modeling nutrients,oxygen and critical phosphorus loading in a shallow reservoir in China with a coupled water quality – Macrophytes model |
| |
| Institution: | 1. Université Grenoble Alpes, CNRS, IRD, LTHE (UMR5564), 38000 Grenoble, France;2. Eawag: Swiss Federal Institute of Aquatic Science and Technology, Surface Waters — Research and Management, CH-6047 Kastanienbaum, Switzerland;3. University of Science and Technology, The University of Danang, 54 Nguyen Luong Bang, Danang, Viet Nam;1. Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Ministry of Education, College of Environment and Planning, Henan University, Kaifeng 475004, China;2. Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China;3. Tianjin Key Laboratory of Earth''s Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China;1. State Key Laboratory of Estuarine and Coastal Research, Institute of Estuarine and Coastal Research, Institute of Eco-Chongming, East China Normal University, 200241, Shanghai, China;2. Yangtze Delta Estuarine Wetland Ecosystem Observation and Research Station (Ministry of Education & Shanghai Science and Technology Committee), 202162, Shanghai, China;3. Institute of Biodiversity Science, School of Life Sciences, Fudan University, 200438, Shanghai, China;4. Shanghai Landscaping & City Appearance Administrative Bureau, 200040, Shanghai, China;5. Yellow River Institute of Hydraulic Research, 450003, Zhenzhou, China;6. Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA, United States |
| |
| Abstract: | Many macrophyte-dominated clear lakes switch to a phytoplankton-dominated turbid state when the lake becomes eutrophic. An existing Yuqiao Reservoir Water Quality Model (YRWQM) and the macrophyte submodel were coupled to simulate the effect of submerged macrophytes on nutrients and dissolve oxygen cycles in a shallow reservoir in China. The level of phosphorus loading in a transition from a clear to turbid state was addressed using the integrated model. The model runs from seedling establishment until dying out, from March 1 to July 18 in 2009. The simulations were performed for a contingent range of P loadings, starting from three different initial conditions. The results indicated that the integrated model improves accuracy of predictions compared to YRWQM. The concentrations of nutrients declined slightly during the macrophyte growth period in the reservoir and dissolved oxygen increased slightly. Although nutrient concentrations increased by submerged macrophyte release during the extinction period, the effect on the nutrients was less than that of transfer with nutrient-rich water. More released nutrients may enhance increases in substantial abundance. The critical phosphorus loading level during a switch from the clear to turbid state was estimated by these scenarios. The threshold for the switch is ∼6.1 mgP m−2 d−1 with an initial total phosphorus concentration of 160 μg l−1. Moreover, the results demonstrated that the switch was also dependent on the initial total phosphorus concentration. These results suggest that the reservoir in a clear water state is at risk of a switch as nutrient levels are close to the critical levels. |
| |
| Keywords: | Submerged macrophytes Model Nutrients cycles Critical loading Alternative stable states Yuqiao Reservoir |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
