Spatial econometric analysis on influencing factors of water consumption efficiency in urbanizing China

Due to the limitation of total amount of water resources, it is necessary to enhance water consumption efficiency to meet the increasing water demand of urbanizing China. Based on the panel data of 31 provinces in China in 1997-2013, we analyze the influencing factors of water consumption efficiency by spatial econometric models. Results show that, 1） Due to the notable spatial autocorrelation characteristics of water consumption efficiency among different provinces in China, general panel data regression model which previous studies often used may be improper to reveal its influencing factors. However, spatial Durbin model may best estimate their relationship. 2） Water consumption efficiency of a certain province may be influenced not only by its socio-economic and eco-environmental indicators, but also by water consumption efficiency in its neighboring provinces. Moreover, it may be influenced by the neighboring provinces＇ socio-economic and eco-environmental indicators. 3） For the macro average case of the 31 provinces in China, if water consumption efficiency in neighboring provinces increased 1%, water consumption efficiency of the local province would increase 0.34%. 4） Among the ten specific indicators we selected, per capita GDP and urbanization level of itself and its neighboring provinces have the most prominent positive effects on water consumption efficiency, and the indirect effects of neighboring provinces are much larger. Therefore, the spatial spillover effects of the economic development level and urbanization level are the primary influencing factors for improving China＇s water consump- tion efficiency. 5） Policy implications indicate that, to improve water consumption efficiency, each province should properly consider potential influences caused by its neighboring prov- inces, especially needs to enhance the economic cooperation and urbanization interaction with neighboring provinces.

Comparison of Water Use Efficiency in Alfalfa Using Water and Waste Water

Growth of cultural and economic level of societies has caused conversion of villages to cities and establishment of wastewater treatment plant in cities. Wastewater treat- ment plants discharge significant amounts of wastewater into natural waterways and their output at the most critical time (the hottest day that crop water need reaches to maximum due to physiological conditions) reaches to the highest amount. Hence, with regard to permanent and accessible wastewater and study on performance and production of forage per water or wastewater consumption unit, the research project was performed in form of statistical plan of totally random blocks with four treatments in three replications during three years. The results indicate that function of forage at the third year of project implementation has increased than the first and second years. Treatments 2 and 4 (the treatments to use wastewater) had greater function than treatments 1 and 3 (treatments that have irrigated with well water), found with significant difference. In average, function of forage (dry and wet) in treatments irrigated with wastewater than the treatments irrigated with well water has been greater to 37 and 32 percent regardless of consumption amount. Water con- sumption efficiency in the treatments to use wells water and wastewater equals to 0.867 and 1.09 kg production of dry hay per cubic meter of water or wastewater.

Elasticity Ratio of Resource Consumption and the Resource Consumption

Today the resources are becoming scarcer, which should not be regarded as unexhausted any more. Correspondingly, the production would be constrained by the scarcity of resources clearly. Then the economic researchers would pay much more attention to reducing the consumption of natural resources in the future. Therefore this paper brings foreword the conception of elasticity ratio of resource consumption based on the concept of elasticity and analyzes the relationship between the parameters. For the certain relationships between the elasticity ratio of resource consumption and resource consumption, this paper will try to reveal, to keep economy growing while resource consumption reducing, what conditions should be met as to the relationships among resource productivity, its growth rate, energy saving efficiency, economic growth rate and elasticity ratio of resource consumption. This paper proves the relationship between the China＇s energy consumption and economy growth using statistic data from 1978 to 2003.

Assessment of Nutrient Leaching Losses and Crop Uptake with Organic Fertilization,Water Saving Practices and Reduced Inorganic Fertilizer

The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge gap.The experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block design.The results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))respectively.Reduced fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving irrigation.Hence,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water pollution.Further studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching losses.The benefits at different climatic conditions,soil types,and fertilizer types with application methods are also a research gap.

Fuel efficiency optimization of tanker with focus on hull parameters

Fuel efficiency optimization is of crucial importance in industries.Marine transportation industry is no exception.Multi-disciplinary optimization is a branch of engineering which uses optimization methods for solving problems in which the objective function is simultaneously affected by several different factors.As one of the tools for this type of optimization,genetic algorithm has a high quality and validity.The objective of the present study is to optimize fuel efficiency in tankers.All presented equations and conditions are valid for tankers.Fuel consumption efficiency of tankers is a function of various influential factors.Given the lack of equations for describing and modeling these factors and unavailability of valid performance database for inferring the equations as well as the lack of literature in this field,the preset study includes five optimizing factors affecting the fuel consumption efficiency of a tanker in genetic algorithm by using the genetic algorithm toolbox of MATLAB software package.