Precipitation variability and land surface changes are the two primary factors that affect basin hydrology, and thus estimation of their impact is of great importance for sustainable development at a catchment scale. In this study, we investigated the long-term changes in precipitation and runoff, from 1961 to 2011, in the Yihe River basin by Mann-Kendall test. A new method of trend pattern was put forward and used to identify the trends of precipitation and runoff, which indicated that the basin had a decreasing trend in annual runoff. The change point occurred in the year 1985 dividing the long-term series into two periods. Precipitation elasticity and linear regression methods were used to quantify the impact of precipitation and land surface change on runoff and provided consistent results of the percentage change in an annual runoff for the postchange period. Use of these methods reveals that the reduction in annual runoff is mainly due to precipitation variability of 56.38–67.68% and land surface change of 43.62–32.32%, as estimated by precipitation elasticity and linear regression methods, respectively. Due to the rapid growth of urbanization, the land surface change increased from 1990 to 2010. The result of this study can provide a reference for the management of regional water resources.

Abstract. The effect of temperature on bio-hydrogen production by co-digestion of sewerage sludge with food waste and its two derivatives, i.e. noodle waste and rice waste, was investigated by statistical modelling. Experimental results showed that increasing temperature from mesophilic (37 • C) to thermophilic (55 • C) was an effective mean for increasing bio-hydrogen production from food waste and noodle waste, but it caused a negative impact on bio-hydrogen production from rice waste. The maximum cumulative biohydrogen production of 650 mL was obtained from noodle waste under thermophilic temperature condition. Most of the production was observed during the first 48 h of incubation, which continued until 72 h of incubation. The decline in pH during this interval was 4.3 and 4.4 from a starting value of 7 under mesophilic and thermophilic conditions, respectively. Most of the glucose consumption was also observed during 72 h of incubation and the maximum consumption was observed during the first 24 h, which was the same duration where the maximum pH drop occurred. The maximum hydrogen yields of 82.47 mL VS −1 , 131.38 mL COD −1 , and 44.90 mL glucose −1 were obtained from thermophilic food waste, thermophilic noodle waste and mesophilic rice waste, respectively. The production of volatile fatty acids increased with an increase in time and temperature in food waste and noodle waste reactors whereas they decreased with temperature in rice waste reactors. The statistical modelling returned good results with high values of coefficient of determination (R 2 ) for each waste type and 3-D response surface plots developed by using models developed. These plots developed a better understanding regarding the impact of temperature and incubation time on bio-hydrogen production trend, glucose consumption during incubation and volatile fatty acids production.

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Population increases by two people in urban cities. In fact, the majority of urban population is blighted and slums due to unsafe and optimal facilities for the community. Here we need to improve the existing sewage facilities with advance, reliable and affordable technologies. The objective of this paper is to introduce some beneficial bacteria that have to restore the water bodies and also helpful to produce an Eco friendly environment.

In this study, variations in the hydrological responses of the Yihe agricultural watershed in the Yihe River Basin in China were analysed based on decadal period data from 1961 to 2011. Precipitation and streamflow data showed a positive trend and evapotranspiration a negative trend. Human activities dominated in the basin for the study period, but the results show inconsistencies between 1989 and 2011. The contribution of human activities and climate variability were quantified through simple linear regression and a physically based modelling approach (hydrological sensitivity). The results suggest that the streamflow of the Dongwan Basin has decreased compared to the baseline period (1961-1968). The contributions of human activities and climate variability were 17% and 83% for 1970-2011 using a simple linear regression approach. The hydrological sensitivity method quantified 119% and-19% of human activities and climate variability respectively for the same period.