Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater c...Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater could serve as a freshwater supply. However, since 20%-30% of the water supply is used for flushing waste from the city, seawater with simple treatment could also partly replace the use of freshwater. In this work, the freshwater saving potential and environmental impacts of the urban water system （water-wastewater closed loop） adopting seawater desalination, seawater for toilet flushing （SWTF）, or reclaimed water for toilet flushing （RWTF） are compared with those of a conventional freshwater system, through a life-cycle assessment and sensitivity analysis. The potential applications of these processes are also assessed. The results support the environmental sustainability of the SWTF approach, but its potential application depends on the coastal distance and effective population density of a city. Developed coastal cities with an effective population density exceeding 3000 persons.km-2 and located less than 30 km from the seashore （for the main pipe supplying seawater to the city） would benefit from applying SWTF, regardless of other impact parameters. By further applying the sulfate reduction, autotrophic denitrification, and nitrification integrated （SANI） process for wastewater treatment, the maximum distance from the seashore can be extended to 60 km. Considering that most modern urbanized cities fulfill these criteria, the next generation of water supply systems could consist of a freshwater supply coupled with a seawater supply for sustainable urban development.展开更多
The increasing number of mountain climbers made them a significant source of anthropopression. The paper is focused on the devastating impact of non-toilet human waste on high-mountain environment and discusses the sc...The increasing number of mountain climbers made them a significant source of anthropopression. The paper is focused on the devastating impact of non-toilet human waste on high-mountain environment and discusses the scale of this phenomenon. Four male members, of mean age 31.5 （±0.5） years, volunteered for this study. The study was conducted above 12,286 feet （3,745 m）, and consisted of 12 days of measuring human excrement output, as well as calorie and liquid consumption. The average results showed the amount of human excrement remains left by climbers in high-mountain environment on a daily scale; i.e., feces of approximately 128 g （32 g without water） and approximately 1.8 L of urine. During this study, the average daily diet consisted of 4,000 （± 500） calories and average 3.6 （± 1.1） quarts （3.8 ± 1 L） of water. Based on these data, an example calculation of quantitative values of human feces and urine left by climbers in 2013 on Denali （Mount McKinley） was conducted. Results show that the 1,151 people that climbed Denali within 18 days （the mean residence time in the massif） left behind over 660 kg of feces and more than 37 thousand liters of urine in the massif in 2013 alone.展开更多
The“toilet improvement”initiative has been actively responded to and implemented across China to improve the local sanitation environment and service quality since 2015..This paper takes Yunnan Province as an exampl...The“toilet improvement”initiative has been actively responded to and implemented across China to improve the local sanitation environment and service quality since 2015..This paper takes Yunnan Province as an example to evaluate the impact of this measure on the competitiveness of ecotourism in rural traditional villages.The ArcGIS tool was used to compare and screen the geographic environmental characteristics of six batches of 778 villages in Yunnan Province that were evaluated as national-level traditional villages in the early stage,and 37 villages with the same elevation changes and slope were selected for a comparative analysis,to reduce the impact of differences in three-dimensional topography and geomorphology.Combined with the TOPSIS comprehensive evaluation method and OLS econometric regression model,this study examined the ecotourism competitiveness of the 37 selected traditional villages and the impact of the toilet improvement initiative on their competitiveness.The results show that the ecotourism competitiveness of traditional villages in Yunnan Province is generally low,and there are obvious hierarchical characteristics.The road choice,regional distribution quantity,distance and service accessibility of public toilet construction have a significant influence on the overall ecotourism competitiveness of the villages in Yunnan Province.Therefore,three suggestions are put forward:strengthen the ecotourism construction of traditional villages in Yunnan Province as a whole and in each local area,pay attention to and strengthen the quantity and quality of construction of the public toilets relevant to ecotourism in traditional villages,and pay attention to the accessibility and service scope of the public toilets in the construction process.展开更多
文摘Global water security is a severe issue that threatens human health and well-being. Finding sustainable alternative water resources has become a matter of great urgency. For coastal urban areas, desalinated seawater could serve as a freshwater supply. However, since 20%-30% of the water supply is used for flushing waste from the city, seawater with simple treatment could also partly replace the use of freshwater. In this work, the freshwater saving potential and environmental impacts of the urban water system （water-wastewater closed loop） adopting seawater desalination, seawater for toilet flushing （SWTF）, or reclaimed water for toilet flushing （RWTF） are compared with those of a conventional freshwater system, through a life-cycle assessment and sensitivity analysis. The potential applications of these processes are also assessed. The results support the environmental sustainability of the SWTF approach, but its potential application depends on the coastal distance and effective population density of a city. Developed coastal cities with an effective population density exceeding 3000 persons.km-2 and located less than 30 km from the seashore （for the main pipe supplying seawater to the city） would benefit from applying SWTF, regardless of other impact parameters. By further applying the sulfate reduction, autotrophic denitrification, and nitrification integrated （SANI） process for wastewater treatment, the maximum distance from the seashore can be extended to 60 km. Considering that most modern urbanized cities fulfill these criteria, the next generation of water supply systems could consist of a freshwater supply coupled with a seawater supply for sustainable urban development.
文摘The increasing number of mountain climbers made them a significant source of anthropopression. The paper is focused on the devastating impact of non-toilet human waste on high-mountain environment and discusses the scale of this phenomenon. Four male members, of mean age 31.5 （±0.5） years, volunteered for this study. The study was conducted above 12,286 feet （3,745 m）, and consisted of 12 days of measuring human excrement output, as well as calorie and liquid consumption. The average results showed the amount of human excrement remains left by climbers in high-mountain environment on a daily scale; i.e., feces of approximately 128 g （32 g without water） and approximately 1.8 L of urine. During this study, the average daily diet consisted of 4,000 （± 500） calories and average 3.6 （± 1.1） quarts （3.8 ± 1 L） of water. Based on these data, an example calculation of quantitative values of human feces and urine left by climbers in 2013 on Denali （Mount McKinley） was conducted. Results show that the 1,151 people that climbed Denali within 18 days （the mean residence time in the massif） left behind over 660 kg of feces and more than 37 thousand liters of urine in the massif in 2013 alone.
基金The Yunnan University of Finance and Economics Graduate Innovation Fund Project(2023YUFEYC118)The Key Project of Philosophy and Social Science Research Base of Yunnan Province(JD2019ZD03)。
文摘The“toilet improvement”initiative has been actively responded to and implemented across China to improve the local sanitation environment and service quality since 2015..This paper takes Yunnan Province as an example to evaluate the impact of this measure on the competitiveness of ecotourism in rural traditional villages.The ArcGIS tool was used to compare and screen the geographic environmental characteristics of six batches of 778 villages in Yunnan Province that were evaluated as national-level traditional villages in the early stage,and 37 villages with the same elevation changes and slope were selected for a comparative analysis,to reduce the impact of differences in three-dimensional topography and geomorphology.Combined with the TOPSIS comprehensive evaluation method and OLS econometric regression model,this study examined the ecotourism competitiveness of the 37 selected traditional villages and the impact of the toilet improvement initiative on their competitiveness.The results show that the ecotourism competitiveness of traditional villages in Yunnan Province is generally low,and there are obvious hierarchical characteristics.The road choice,regional distribution quantity,distance and service accessibility of public toilet construction have a significant influence on the overall ecotourism competitiveness of the villages in Yunnan Province.Therefore,three suggestions are put forward:strengthen the ecotourism construction of traditional villages in Yunnan Province as a whole and in each local area,pay attention to and strengthen the quantity and quality of construction of the public toilets relevant to ecotourism in traditional villages,and pay attention to the accessibility and service scope of the public toilets in the construction process.
