The construction of a dam converts the natural streamflow to human control. It is necessary to learn the accumulated effect of cascade dams on hydrological characteristics, sediment and nutrient pollution discharge. The current research describes the analysis and simulation of streamflow, sand concentration and nutrient pollutant discharge alterations caused by the construction of a cascade of eight dams along the Longliu section of the upper stream of the Yellow River. The analysis shows that the maximum monthly streamflow difference between the inlet and outlet of the Longliu section decreased from 430 to 115 m 3 /s, after the appearance of the cascade dams between 1977 and 2006. In the same period, the correlation coefficient (R 2 ) of monthly streamflow between the inlet and outlet of Longliu dropped from 0.959 to 0.375. The peak of streamflow shifted from June to May and October. The difference in sand concentration between two sections decreased from 0.52 to 0.39 kg/m 3 , which was the direct consequence of the operation of the reservoirs. The R 2 value of sand concentrations of the inlet and outlet were also reduced from 0.504 to 0.356. A t-test analysis indicates that the original hydrological nature was significantly disturbed by the cascade dams. The influence of the dams on nutrient pollutant transport was simulated by the SWAT model. This simulation suggests that the cascade dams decreased the discharge of total nitrogen and total phosphorus from 15.4 × 10 3 t and 1,996 t to 0.4 × 10 3 t and 328 t, respectively. In conclusion, the accumulated impact of cascade dams on streamflow, sand concentration and nutrient pollutant discharge were analyzed, which were helpful for understanding the environmental features of the entire watershed. 914 W. Ouyang et al.

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Intensive agricultural development can change land use, which can further affect regional ecosystem services and functions. With the rapid growth of the population and the national demand for food, the northeast of China, which is located in the high latitudes, has experienced four agricultural developments since the 1950s. The original wetlands of this area were developed for farmland. The evaluation of ecosystem services is conducted to reveal the ecosystem status and variable trends caused by land reclamation. The aim of this study is to provide scientific basis for environmental management and for the sustainable development of agriculture in Northeast China. With GIS-RS technology, a typical farm was chosen to analyze variations in the ecosystem service value in response to land use changes during the study period. The total ecosystem service value of the farm decreased from 7523.10 million Yuan in 1979 to 4023.59 million Yuan in 2009 with an annual rate of -1.6 % due to the decreasing areas of woodland and wetland. The increased areas of cropland, water area and grassland partly offset the loss of the total value, but the loss was still greater than the compensation. Waste treatment and climate regulation were the top two service functions with high service values, contributing to approximately 50 % of the total service value. The spatial difference of the ecosystem service value also was analyzed. The wetlands located in the central and northeastern sections of the farm changed significantly. From the aspect of ecosystem service value, the wetland and water area should be conserved, as they have the highest value coefficients. The accuracy of the value coefficient, however, needs to be studied further in future research.

The intelligent wearable sensors promote the transformation of the health care from a traditional hospital-centered model to a personal portable device-centered model. There is an urgent need of real-time, multi-functional, and personalized monitoring of various biochemical target substances and signals based on the intelligent wearable sensors for health monitoring, especially wound healing. Under this background, this review article first reviews the outstanding progress in the development of intelligent, wearable sensors designed for continuous, real-time analysis, and monitoring of sweat, blood, interstitial fluid, tears, wound fluid, etc. Second, this paper reports the advanced status of intelligent wound monitoring sensors designed for wound diagnosis and treatment. The paper highlights some smart sensors to monitor target analytes in various wounds. Finally, this paper makes conservative recommendations regarding future development of intelligent wearable sensors.

Water fluctuation is the main triggering factor of reservoir slope failures, especially in the area of the Three Gorges Reservoir of China. Fluctuation velocity of reservoir water and hydraulic properties of soil as defined by soil-water characteristic curve (SWCC), saturated permeability coefficient and unsaturated permeability function are key potential properties that control reservoir landslide stability. The effect of reservoir water fluctuation velocity and hydraulic properties of soil on landslide stability are investigated through a series of numerical simulations with different parameters. The results of simulations show that fitting parameters in the SWCC [i.e., a, n, m for Fredlund and Xing (Can Geo J, 31(3):521-532. ) equations] have significant effect on the stability of landslide for reservoir water's drawdown or impounding process. The saturated permeability coefficient of soil and velocity of water level fluctuation have comprehensive (defined as Impact Factor, a) and significant influence on the stability of reservoir landslide. A relative equation: m [ a [ n [ a has been drawn for the susceptibility of effect on the stability of reservoir landslide for the parameters

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