Although the subject of mining and its environmental impacts are very wide to be covered in this review, concerns about the impact of phosphate mining and processing typically emphasis on its potential effects on water pollution, air pollution, and human health were accessed. We reviewed published information at different stages of mining; current mines, closed old mines and reclaimed mines and at different complexity of mining; surface mining, underground mining and sea-bed phosphorite mining. Information was analyzed to understand the association of toxic metals and radioactive elements in the phosphate rocks and to trace the transfer pathways of toxic metals and radioactive elements from the phosphate rocks to the environment. According to the reviewed results the major environmental impacts of phosphate mining and processing on the water resources were: impacts on the hydrology by phosphate industry water usage and landscape changes, and impacts on water quality by discharges of industry wastewater into the waterways. Dust was a common air quality problem throughout all mining activities; fluoride emissions and radon gas emission were also serious problems. Toxic metals and radioactive elements of significant human health problems were Pb, Cd, Hg, Cr, As, U Th and Ra. Most researches agreed that 226 Ra is considered as one of the most toxic radionuclide. The nuclide is of further importance as the parent nuclide of the gaseous 222 Rn which, along with its solid decay products, constitutes a significant source of radiation exposure. Scientific researches on mine water drainage and phosphate mining relationship may help to understand the environmental impacts associated with water resource and water quality.

Abstract. Flooding represents one of the most severe natural disasters threatening the development of human society. A model that is capable of predicting the hydrological responses in watershed with management practices during flood period would be a crucial tool for pre-assessment of flood reduction measures. The Soil and Water Assessment Tool (SWAT) is a semi-distributed hydrological model that is well capable of runoff and water quality modeling under changed scenarios. The original SWAT model is a long-term yield model. However, a daily simulation time step and a continuous time marching limit the application of the SWAT model for detailed, event-based flood simulation. In addition, SWAT uses a basin level parameter that is fixed for the whole catchment to parameterize the unit hydrograph (UH), thereby ignoring the spatial heterogeneity among the sub-basins when adjusting the shape of the UHs. This paper developed a method to perform event-based flood simulation on a sub-daily timescale based on SWAT2005 and simultaneously improved the UH method used in the original SWAT model. First, model programs for surface runoff and water routing were modified to a sub-daily timescale. Subsequently, the entire loop structure was broken into discrete flood events in order to obtain a SWAT-EVENT model in which antecedent soil moisture and antecedent reach storage could be obtained from daily simulations of the original SWAT model. Finally, the original lumped UH parameter was refined into a set of distributed ones to reflect the spatial variability of the studied area. The modified SWAT-EVENT model was used in the Wangjiaba catchment located in the upper reaches of the Huaihe River in China. Daily calibration and validation procedures were first performed for the SWAT model with long-term flow data from 1990 to 2010, after which sub-daily (Δt=2 h) calibration and validation in the SWAT-EVENT model were conducted with 24 flood events originating primarily during the flood seasons within the same time span. Daily simulation results demonstrated that the SWAT model could yield very good performances in reproducing streamflow for both whole year and flood period. Event-based flood simulation results simulated by the sub-daily SWAT-EVENT model indicated reliable performances, with ENS values varying from 0.67 to 0.95. The SWAT-EVENT model, compared to the SWAT model, particularly improved the simulation accuracies of the flood peaks. Furthermore, the SWAT-EVENT model results of the two UH parameterization methods indicated that the use of the distributed parameters resulted in a more reasonable UH characterization and better model fit compared to the lumped UH parameter.

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With the rapid growth of various complex networks, link prediction has become increasingly important because it can discover the missing information and predict future interactions between nodes in a network. Recently, the CAR and CCLP indexes have been presented for link prediction by means of different triangle structure information. However, both indexes may lose the contributions of some shared neighbors. We propose in this work a new index to make up the weakness and then improve the accuracy of link prediction. The proposed index focuses on a new triangle structure, i.e., the triangle formed by one seed node, one common neighbor, and one other node. It emphasizes the importance of these triangles but does not ignore the contribution of any common neighbor. In addition, the proposed index adopts the theory of resource allocation by penalizing large-degree neighbors. The results of comparison with CN, AA, RA, ADP, CAR, CAA, CRA, and CCLP on 12 real-world networks show that the proposed index outperforms the compared methods in terms of AUC and ranking score.