Does Urbanization Improve Industrial Water Consumption Efficiency?

Although some studies have focused on the logical connection between industrial water consumption in the industrial economic development (IED) and industrial wastewater treatment (IWT) stages, the master–slave game relationship between these stages has not been considered. This study selected panel data from 30 provinces in China from 2011 to 2015, divided these provinces into IED- and IWT-dominated regions, and developed a two-stage data envelopment analysis (DEA) model based on the master–slave game relationship between the IED and IWT stages. In addition, a regression model based on the Simar–Wilson approach was constructed to reveal the effects of urbanization on industrial water consumption efficiency. The results show that the industrial water consumption efficiency in China slightly fluctuated from 2011 to 2015, and there was no significant efficiency improvement. The efficiency of the IED stage was generally higher than that of the IWT stage, and the efficiency gap between stages was smaller in IED-dominated regions than in IWT-dominated regions. Urbanization has different effects on industrial water consumption efficiency, and the same factor can have significantly different effects in different regions. Some policy implications are proposed for the different types of regions.

Greenhouse crisphead lettuce grown with mulching and under different soil water tensions

ABSTRACT Proper irrigation management is important both to enable adequate water supply and to minimize problems with diseases, nutrient leaching and unnecessary water and power wastes. Thus, this study aimed at improving irrigation management in greenhouses. For that reason, we assessed the effect of various water tensions on yield performance of crisphead lettuce, Raider-Plus cv. , grown with mulching. The experiment was conducted in greenhouse at the Federal University of Lavras. Treatments constituted five different soil water tensions, namely 12, 25, 35, 45, and 70 kPa. The results showed that irrigation must be carried out at water soil tension of around 12 kPa to reach satisfying commercial values for both total and commercial yield, 66 and 50 t ha-1, as well as keeping good vegetable quality. At this tension, total water consumption was of 167.25 mm. The water use efficiency demonstrated quadratic response to treatments, with high water consumption efficiency found in intermediate treatments (35 and 45 kPa), achieving values of 579.87 and 471.71 kg ha -1mm-1, respectively.