Phosphorus Fractions in the Sediments of Yuecheng Reservoir, China
School of Water Conservancy and Hydroelectric Power, Hebei University of Engineering, Handan 056002, China
Department of Earth Sciences, University of the Western Cape, Cape Town 7535, South Africa
Authors to whom correspondence should be addressed.
Water 2019, 11(12), 2646; https://doi.org/10.3390/w11122646
Received: 16 September 2019 / Revised: 11 December 2019 / Accepted: 12 December 2019 / Published: 15 December 2019
(This article belongs to the Special Issue Lake and River Restoration: Method, Evaluation and Management)
As a result of the inexorable development of the economy and the ever-increasing population, the demand for water in the urban and rural sectors has increased, and this in turn has caused the water quality and eutrophication of the reservoir to become a legitimate concern in the water environment management of river basins. Phosphorus (P) is one of the limiting nutrients in aquatic ecosystems; P in the sediment is a primary factor for eutrophication. Yuecheng Reservoir is located in one of the most productive and intensively cultivated agricultural regions in North China. Detailed knowledge of the sediment is lacking at this regional reservoir. The first study to look into the different P fractions and its diffusion fluxes at the water sediment interface of the Yuecheng Reservoir makes it possible to learn about the internal P loading. According to the results, the concentrations of total phosphorus (TP) ranged from 1576.3 to 2172.6 mg kg and the P fraction concentration sequence is as follows: P associated with calcium (Ca–Pi) > organic P (Po) > P bound to aluminum (Al), ferrum (Fe) and manganese (Mn) oxides and hydroxides (Fe/Al–Pi). The results demonstrated that, although the construction of a large number of water conservancy projects in the upper reaches of the river resulted in the decrease of inflow runoff, the pollutions from terrestrial plants or materials played a key role in the sediment phosphorus fraction, and they should be emphasized on the water environment management of river basin.