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1.
Int J Hyg Environ Health ; 223(1): 256-266, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31444118

RESUMO

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are a chemical class widely used in industrial and commercial applications because of their unique physical and chemical properties. Between 2013 and 2016 PFAS were detected in public water systems and private wells in El Paso County, Colorado. The contamination was likely due to aqueous film forming foams used at a nearby Air Force base. OBJECTIVE: To cross-sectionally describe the serum concentrations of PFAS in a highly exposed community, estimate associations with drinking water source, and explore potential demographic and behavioral predictors. METHODS: In June 2018, serum PFAS concentrations were quantified and questionnaires administered in 213 non-smoking adult (ages 19-93) participants residing in three affected water districts. Twenty PFAS were quantified and those detected in >50% of participants were analyzed: perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA) and perfluoroheptane sulfonate (PFHpS). Unadjusted associations were estimated between serum PFAS concentrations and several predictors, including water consumption, demographics, personal behaviors and employment. A multiple linear regression model estimated adjusted associations with smoking history. RESULTS: Study participants' median PFHxS serum concentration (14.8 ng/mL) was approximately 12 times as high as the U.S. national average. Median serum concentrations for PFOS, PFOA, PFNA and PFHpS were 9.7 ng/mL, 3.0 ng/mL, 0.4 ng/mL and 0.2 ng/mL, respectively. Determinants of PFHxS serum concentrations were water district of residence, frequency of bottled water consumption, age, race/ethnicity, and smoking history. Determinants of serum concentrations for the other four PFAS evaluated included: water district of residence, bottled water consumption, age, sex, race/ethnicity, smoking history, and firefighter or military employment. CONCLUSIONS: Determinants of serum concentrations for multiple PFAS, including PFHxS, included water district of residence and frequency of bottled water consumption. Participants' dominant PFAS exposure route was likely consumption of PFAS-contaminated water, but certain demographic and behavioral characteristics also predicted serum concentrations.

2.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-LISBR1.1-46898

RESUMO

Plataforma com dados indicadores sobre a Taxa de mortalidade atribuída a fontes de água inseguras, saneamento inseguro e falta de higiene. Agenda 2030 - objetivo 3 - Saúde e bem estar


Assuntos
Desenvolvimento Sustentável , Saneamento Básico/políticas
3.
Sci Total Environ ; 699: 134225, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677463

RESUMO

Water and energy conservation are indispensable commitments to achieve the sustainable development of the iron and steel industry. Hereby, this study established an evaluation framework to model the water and energy consumption in the iron and steel industry. This framework quantitatively assessed the energy and water saving with adoption of conventional and emerging technologies. Thirty mainstream technologies, among which 21 focused on energy saving and the remaining 9 focused on water saving, were selected for analysis. Five scenarios were developed to examine systematic water- and energy-saving potentials, including benchmark (BM) scenario, constrained product (CP) scenario, business as usual (BAU) scenario, and benefit/cost-driven (BD) scenario and strengthened policy (SP) scenario. The results show that the energy-saving potentials of BAU, BD and SP scenarios are 1.75 PJ, 1.21 PJ and 1.65 PJ, respectively. The water-saving potentials of BAU, BD and SP scenarios are 4.83 billion m3, 5.71 billion m3 and 9.15 billion m3, respectively. The specific energy consumption and water consumption decreased to 15.01-15.59 GJ/t and 54.13-58.77 m3/t, respectively. This study suggested to implement encouraging policies in prompt popularity rate of technologies, and promote energy-saving and water-saving technologies to achieve sustainable development of iron and steel industry.

4.
Sci Total Environ ; 699: 134255, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31683215

RESUMO

Citizen science (CS) may be described as research carried out by members of the public with the aim of gathering scientific information for the purpose of aiding in scientific projects. It has many potential advantages, including data collection at a scale not possible by professional scientists alone. The United Nations (UN) has recently recognized citizen science as a potential source of data that may contribute to the UN Sustainable Development Goals (SDGs). The availability of relatively inexpensive water quality monitoring field equipment suitable for CS suggests great potential for increased spatial coverage far beyond that of traditional, laboratory-based monitoring networks for water quality. In support of work towards the achievement of Sustainable Development Goal 6: "Clean Water and Sanitation", this study tested the use of such field equipment by citizen scientists for SDG Indicator 6.3.2: "Proportion of bodies of water with good ambient water quality". Data generated by 26 citizen scientists were compared with the results produced by an accredited laboratory. The results compared well for most parameters, suggesting that citizen science may be able to contribute towards monitoring ambient water quality for the Sustainable Development Goals.

5.
Am J Hum Biol ; : e23345, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697009

RESUMO

Water insecurity-the lack of adequate and safe water for a healthy and productive life-is one of the greatest threats facing humans in the coming century. By 2030, half of the world is expected to be living in water-stressed conditions, given current climate change scenarios. A key goal of the UN Water Action Decade and Sustainable Development Goal 6 is to improve water security for the three billion people globally affected, but the future looks grim. For many communities, from Cape Town, South Africa to Flint, United States, the imagined dystopian future of severe water shortages has already arrived-shaped not so much by lack of water, but by aging infrastructure, underfunded utilities, social exclusion, politicized commodification, and environmental racism. Stepping off from my biocultural research in Cochabamba, Bolivia, I discuss how recent research is dramatically advancing our understanding of water insecurity, such as new findings around the biocultural causes and consequences of dehydration, contamination, and water stress. But, much more needs be done to support local communities in creating fair and just water systems. I discuss how human biologists can make crucial contributions toward the advancement of a much-needed science of water insecurity, while highlighting some practical and ethical challenges to advancing a core mission of providing safe, sufficient water to all.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31671669

RESUMO

Water resources utilization, social economy development, and ecological environment protection are key factors in regional sustainable development. Scientific evaluation of regional coordinated development status and diagnosis of regional uncoordinated development constraints will improve the management level of decision-makers. At present, most developing countries have the problem of unbalanced regional development caused by the one-sided pursuit of a certain system. Taking 14 prefecture-level cities in Hunan Province as cases, this paper analyzed the spatial and temporal distribution characteristics of the carrying capacity level of the water resources system, the development level of the social economy system and the protection level of the ecological environment system in each evaluation unit based on entropy weight method and order parameter analysis. Based on the theory of coordinated development, a calculation model of a coordinated development degree was constructed, and the corresponding evaluation criteria were formulated. The spatial and temporal distribution characteristics of a coordinated development degree in each research unit were analyzed and evaluated. The results showed that the average coordinated development degree of Hunan Province from 2004 to 2016 evolved from "Light disorder recession" to "Nearly disorder recession", then to "Reluctance coordinated development". Restricted by different systems, the coordinated development degree in each research unit presented spatial and temporal differences. According to different development stages and the characteristics of different regions, corresponding development strategies can be formulated to provide the guidance for coordinated the development of regions.

7.
Sci Total Environ ; : 134657, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31753495

RESUMO

China has established the River Chief System (RCS) to develop mechanisms to achieve success in cross-regional negotiations of the Sustainable Water Resource Management Affairs (SWRMA). This paper aims to investigate the mechanisms developed by RCS and social welfare brought by RCS in China, and thereafter put forward suggestions for the future development of RCS. Therefore, a one-stage cooperation game was used to investigate cross-regional SWRMA negotiations with RCS. The results showed that RCS ensures that cooperative solutions are chosen in cross-regional SWRMA negotiations. Moreover, this paper used a two-stage game to explore cross-regional SWRMA negotiations without involving RCS. In this case, the involvement of the upper-level administrators and the probability of a successful negotiation are endogenously determined by local authorities. The results showed that in cross-regional SWRMA negotiations, both when the upper-level administrators are involved in the first stage and in the second stage, the cooperative solutions would be adopted. Thus, RCS is an inevitable outcome of the cross-regional SWRMA negotiations. In addition, RCS could help to avoid transactional costs and external costs in cross-regional SWRMA negotiations. Based on these results, this study provided the following suggestions: the river chief and local authorities of RCS should be stakeholders; the major members of RCS should be the local authorities influenced mostly by SWRMA quantities; RCS should actively advertise the benefits and the cost-down of SWRMA.

8.
Sci Total Environ ; 694: 133766, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756819

RESUMO

The recently adopted UN Sustainable Development Goals (SDGs) encompasses a specific goal for water (SDG-6). The target 6.4 deals with water scarcity and refers to two main indicators: water use efficiency and water stress (WS), monitored by the UN statistical services yearly at the country level. Yet, for more efficient development planning, indicators should also be provided with higher spatial and temporal resolutions. This study presents a data-driven method allowing to disaggregate the WS indicator at higher spatial and temporal resolution. We applied the method for the Medjerda catchment in Tunisia, known as being severely water-stressed. We disaggregated the WS indicator from the overall catchment to the administrative regional level at yearly and monthly scales. In order to overcome poorly documented irrigation water withdrawals, two approaches were adopted: 1) we used yearly governmental data at both catchment and regions scales; 2) we replaced governmental irrigation data by remote sensing-based irrigation estimation. First Order Uncertainty Analysis (FOUA) was performed to characterize the uncertainty associated with the assessment of WS. Results reveal that the WS at the scale of the catchment increases considerably in recent years, exceeding 50% from 2005 and surpassing the 100% threshold in 2015 and 2016 (102%, 108% respectively). The two adopted approaches result in similar WS trends. However, the second approach yields higher WS values compared to the first approach (144% versus 108% in 2016). The monthly-disaggregated WS at catchment scale exhibits a similar increasing trend. The highest WS values are at the end of the fall and during the summer season, which is mainly due to the increasing demand for irrigation and drinking water. Siliana region is the most affected by WS, while Beja is the least affected. The FOUA shows that the integration of remote sensing-based irrigation data reduces the WS uncertainty.

9.
J Environ Manage ; 254: 109750, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726279

RESUMO

Decision-making associated with the promotion of water sustainability is subjected to uncertainties arising, on the one hand, from the current capacity of understanding socio-environmental systems and their temporality, complexity and multidimensionality; and, on the other hand, from the need to represent key aspects of these systems through data and information. Such a representation is often supported by indicators, indices and systems of indicators for relevant aspects of the problem and for a scenario under analysis. In this context, the main aim of this study was to develop a novel system of indicators for water sustainability assessment in river basins. Literature review and content analysis were used to define an analytical structure for the problem from the perspective of the natural, social and built capitals of related sustainable development assessment. Each capital has been hierarchically subdivided into categories, subcategories and attributes, leading to 54 aspects for water sustainability assessment. A list of indicators was compiled from the scientific and technical literature, linked to attributes, and associated with valuation ranges. This led to the proposition of the River Basin Water Sustainability Index (RBWSI) and sub-indices associated with categories and subcategories of the model. The timeframe and territorial scale relevant for assessment were defined as five-to-ten year periods and areas under the jurisdiction of river basin management committees, respectively. The new model and index thus proposed may be useful in water sustainability diagnostic and prognostic studies, such as required to assess the effectiveness of river basin management actions aimed at promoting sustainable development.

10.
Environ Monit Assess ; 191(12): 757, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741091

RESUMO

Landuse change significantly alters the hydrologic characteristics of the land surface within a watershed. In the present study, the impact of landuse change (2006-2016) on runoff and sediment yield has been assessed in Patiala-Ki-Rao watershed (5140 ha) located in Shivalik foot-hills, using remote sensing, geographical information system (GIS), and Water Erosion Prediction Project (WEPP) watershed model. The watershed has seven major landuse classes, namely agriculture, built-up, fallow land, forest, grass land, streams, and water bodies. The landuse change analysis indicated that the area under all the landuses decreased except built-up that increased by 372.27 ha (112.04%). Forest is the most affected landuse among all watershed landuses that shrinked by 194.90 ha followed by agriculture (64.57 ha), grass land (50.81 ha), streams (30.42 ha), fallow land (21.86 ha), and water bodies (9.72 ha). Runoff and sediment yield for the landuse of the years 2006 and 2016 were simulated by the WEPP model using two climate scenarios (2006 and 2016). The simulated runoff, sediment yield, and sediment delivery ratio increased by 18.62%, 48.04%, and 32.23% under Climate-2006 and 26.78%, 30.23%, and 16.09% under Climate-2016 due to change in landuse during a period of 10 years. This clearly indicates that landuse change in 10 years has greatly influenced the hydrology of the watershed and requires urgent land allocation policy in place for sustainable development in the area.

11.
Water Res ; 170: 115269, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31739243

RESUMO

The Sustainable Development Goals recognize that the availability and quality of improved water sources affect how households use and benefit from these sources. Although unreliability in piped water supplies in low- and middle-income countries (LMICs) has been described, few studies have assessed household coping strategies in response to unreliable water supplies and associated health outcomes. We characterized unreliability in the piped water supply of the town of Borbón, Ecuador over the twelve years following a major upgrade, as well as household coping strategies and associations with diarrhea. We examined trends in primary and secondary drinking water sources, water storage, and water treatment using longitudinal data collected from 2005 to 2012. In 2017, a follow-up survey was administered (N = 202) and a subset of 84 household water samples were tested for chlorine residual levels and microbial contamination. From 2005 to 2017, access to a household water connection increased from 19.4% to 90.3%. However, reliability decreased over time, as in the latter half of 2009, households had access to piped water 79% of the time, compared to 63% by 2017. Piped water samples were highly contaminated with total coliforms (100% of samples) and Escherichia coli (89% of samples). From 2005 to 2017, households less likely to report drinking water treatment (50.6%-5.0%). And from 2009 to 2017, bottled water was increasingly consumed as the primary drinking water source (18.8%-62.4%). From 2005 to 2012, having a household connection was not statistically significantly associated with diarrhea case status (OR: 0.86 95%CI: 0.53, 1.39). Neither household water treatment nor bottled water consumption were negatively associated with diarrhea. Increased water storage was associated with diarrhea (OR: 1.33 per 10L of water stored, 95%CI: 1.05, 1.69). Household water treatment, and consumption of purchased bottled water, two coping strategies that households may have undertaken in response to an unreliable water supply, were not associated with a reduced likelihood of diarrhea. These data suggest a need to understand how impoverished rural households in LMICs respond to unreliable water supplies, and to develop heath messaging appropriate for this context.

12.
Water Res ; 170: 115301, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31765825

RESUMO

Coastal aquifers provide an important source of water globally. Understanding how groundwater responds to changes in rainfall recharge is important for sustainable development. To this end, we investigate how water isotopes (18O, 2H, 3H) and chloride (Cl) concentrations within an island freshwater lens respond under varying rainfall conditions in a region experiencing climate change. Uniquely, this study presents a three year dataset of groundwater collected seasonally between May 2013 and August 2016 from ten wells. Variation in all tracers was observed. The Cl and tritium (3H) show opposing seasonal variation in some sections of the lens, with higher Cl observed in the austral summer when less rainfall occurs and evapotranspiration is highest. The opposite occurs in the austral winter months when 3H increases from atmospheric input via rainfall recharge, and Cl is diluted. An overall decline in 3H values and enrichment in stable water isotopes over the study period was also observed. This study shows that understanding groundwater of freshwater lenses should not rely on a single sampling campaign because seasonal variability is large. The identification of a dual recharge regime, with contributions from both winter rainfall and episodic events, has important implications for understanding the future fate of the freshwater lens on Rottnest Island. The finding that episodic rainfall is a major contributor to groundwater recharge is important and can only be assessed with a multi-year isotope dataset for groundwater and rainfall.

13.
ACS Appl Mater Interfaces ; 11(45): 42149-42155, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31633325

RESUMO

Conversion of CO2 into value-added chemicals with a facile hydrogen source such as water is always of great interest for sustainable development. In this work, a simple and efficient method of reduction of bicarbonate to formate on a simple Ni powder catalyst with water as the facile hydrogen source and Zn as the regenerable reductant is proposed. The Ni catalyst and in situ formed Zn/ZnO exhibited a synergetic catalytic activity in the conversion of bicarbonate into formate, and a good formate yield of 81% was obtained. Detailed studies revealed that the synergetic catalytic activity between Ni and the in situ formed Zn/ZnO was mainly attributed to (i) the inhibited oxidation of Zn by Ni, leading to more interface of Zn/ZnO; (ii) the decreased growth of ZnO crystal along the [0001] direction, and thus increasing the more polar (0001) Zn face and the (0001̅) O face, which have high activity; and (iii) the enhanced generation of more oxygen vacancies at the Zn/ZnO interface to promote the formate yield. This research demonstrates an efficient method of using a simple and nonprecious metal catalyst for the CO2 reduction into value-added chemicals and provides a better understanding of the synergistic catalytic mechanism of Ni and Zn/ZnO.

14.
Glob Chang Biol ; 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31638295

RESUMO

The world's largest afforestation programs implemented by China made a great contribution to the global "greening up." These programs have received worldwide attention due to its contribution toward achieving the United Nations Sustainable Development Goals. However, emerging studies have suggested that these campaigns, when not properly implemented, resulted in unintended ecological and water security concerns at the regional scale. While mounting evidence shows that afforestation causes substantial reduction in water yield at the watershed scale, process-based studies on how forest plantations alter the partitioning of rainwater and affect water balance components in natural vegetation are still lacking at the plot scale. This lack of science-based data prevents a comprehensive understanding of forest-related ecosystem services such as soil conservation and water supply under climate change. The present study represents the first "Paired Plot" study of the water balance of afforestation on the Loess Plateau. We investigate the effects of forest structure and environmental factors on the full water cycle in a typical multilayer plantation forest composed of black locust, one of the most popular tree species for plantations worldwide. We measure the ecohydrological components of a black locust versus natural grassland on adjacent sites. The startling finding of this study is that, contrary to the general belief, the understory-instead of the overstory-was the main water consumer in this plantation. Moreover, there is a strict physiological regulation of forest transpiration. In contrast to grassland, annual seepage under the forest was minor in years with an average rainfall. We conclude that global long-term greening efforts in drylands require careful ecohydrologic evaluation so that green and blue water trade-offs are properly addressed. This is especially important for reforestation-based watershed land management, that aims at carbon sequestration in mitigating climate change while maintaining regional water security, to be effective on a large scale.

15.
PLoS One ; 14(10): e0223557, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603926

RESUMO

BACKGROUND: The critical importance of safe and affordable access to water, sanitation and hygiene (WASH) is highlighted in Goal 6 of the Sustainable Development Goals, which seeks to achieve universal and equitable access for all by 2030. However, people with disabilities-who comprise 15% of the global population-frequently face difficulties meeting their WASH needs. Unmet WASH needs amongst people with disabilities may not be captured through current approaches to tracking progress towards Goal 6, which focus on household- rather than individual-level access. OBJECTIVE: To evaluate access to safe water, sanitation and hygiene (WASH), at the individual- and household-level, amongst people with disabilities in the Tanahun district of Nepal. METHODS: A population-based survey of disability was conducted from August-October 2016 to evaluate access to improved water and sanitation facilities between households with members with disabilities (n = 198) and those without (n = 1,265) in the Tanahun district of Nepal. A nested case-control then compared individual-level access between cases aged 15 and above with disabilities (n = 192) and age-sex-location matched controls without disabilities (n = 189), using the newly developed 21-item "Quality of WASH Access" questionnaire. Multivariate regression was used to compare household- and individual-level indicators between people and households with and without disabilities. In-depth interviews with 18 people with disabilities and their caregivers was conducted to assess the acceptability and appropriateness of the "Quality of WASH Access" questionnaire. FINDINGS: There were no significant differences between households with and without members with disabilities in access to an improved sanitation facility or water source. However, at the individual-level, people with disabilities experienced significantly greater difficulties accessing water, sanitation and hygiene compared to people without disabilities (p<0.001 for all three scores). Amongst people with disabilities, water difficulty scores were associated with having a physical impairment and greater disability severity; sanitation difficulty scores were associated with lower socioeconomic status and physical or self-care limitations; and hygiene difficulty scores were positively associated with self-care limitations and lower socioeconomic status, and inversely associated with hearing impairments. Qualitative research found the "Quality of WASH Access" questionnaire was well understood by participants and captured many of the challenges they faced. Additional challenges not covered by the tool included: (1) time spent on WASH, (2) consistency of access, (3) sufficiency of access, and (4) dignity of access. CONCLUSION: People with disabilities face substantial challenges to meeting their WASH needs, particularly in using services autonomously, consistently, hygienically, with dignity and privacy, and without pain or fear of abuse. These challenges are not captured through household-level data, and so individual-level WASH access are needed to monitor progress towards universal WASH access. The Quality of WASH Access questionnaire may provide a useful data collection tool.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31652610

RESUMO

Translational research applies scientific techniques to achieve practical outcomes, connecting pure research and pure practice. Many translational research types have arisen since the mid-1900s, reflecting the need to better integrate scientific advancement with policy and practice. Water, sanitation, and hygiene (WaSH) development efforts have aimed to reduce morbidity and mortality and improve service delivery; thus, associated research has a strong orientation toward applied studies that use diverse methods to support decision-making. Drawing from knowledge that emerged to support other professional fields, such as manufacturing and clinical healthcare, we characterize different types of translational research and clarify nomenclature and principles. We describe study approaches relevant to translational research questions, and offer overarching recommendations, specific examples, and resources for further study as practical advice to professionals who seek to apply translational methods to WaSH problems. To enhance collective outcomes, professionals should mindfully align projects within the translational spectrum. We further recommend overarching good practices such as documenting intervention adaptations, overtly considering contextual factors, and better distinguishing efficacy from effectiveness research by replicating studies in different contexts. By consciously improving the compatibility and linkages between WaSH science and practice, this guide can accelerate urgently needed progress toward global development goals.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31575024

RESUMO

It is of great significance to deal with the relationship between external factors and the water-energy-food internal system for China's sustainable development. This paper takes China as the research object, uses the system dynamics method to construct a model for China's water-energy-food system, and introduces the "two-child" policy and trade friction as the scenario parameters for simulation. The main results of scenario simulation can be summarized as the following three points. In terms of water, the trade friction will hinder China's industrial water consumption into a low-consumption stage. In terms of energy, both the trade friction and the "two-child" policy, will not change the increasing trend of energy demand. In terms of food, if there is strong response to the "two-child" policy, there will be insufficient food inventory under the current capacity and import ratio. In short, this paper takes the sustainable development of water-energy-food as a starting point and puts forward policy suggestions on the comprehensive formulation of policies.

18.
Risk Anal ; 39(10): 2214-2226, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31529800

RESUMO

Achieving health gains from the U.N. Sustainable Development Goals of universal coverage for water and sanitation will require interventions that can be widely adopted and maintained. Effectiveness-how an intervention performs based on actual use-as opposed to efficacy will therefore be central to evaluations of new and existing interventions. Incomplete compliance-when people do not always use the intervention and are therefore exposed to contamination-is thought to be responsible for the lower-than-expected risk reductions observed from water, sanitation, and hygiene interventions based on their efficacy at removing pathogens. We explicitly incorporated decision theory into a quantitative microbial risk assessment model. Specifically, we assume that the usability of household water treatment (HWT) devices (filters and chlorine) decreases as they become more efficacious due to issues such as taste or flow rates. Simulations were run to examine the tradeoff between device efficacy and usability. For most situations, HWT interventions that trade lower efficacy (i.e., remove less pathogens) for higher compliance (i.e., better usability) contribute substantial reductions in diarrheal disease risk compared to devices meeting current World Health Organization efficacy guidelines. Recommendations that take into account both the behavioral and microbiological properties of treatment devices are likely to be more effective at reducing the burden of diarrheal disease than current standards that only consider efficacy.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31561464

RESUMO

To make environmental management decisions more executive and targeted, it is essential for decision-making to include local residents' perceptions and preferences for ecosystem services (ES) and biodiversity (BD). This study conducted a questionnaire survey with 386 local residents to explore social perceptions for ES and BD in the Fenghe River watershed. ES contain food from agriculture (AGR), food from livestock (LIV), fresh water (FW), air purification (AP), water purification (WP), water retention (WR), soil retention (SR), aesthetics (AES), recreation (RE), and spirit (SP) in this study. Ranking and Likert scales are combined to identify residents' preferences for ES and BD. The hypothetical market method is used to identify the willingness to pay for BD and ES. Independent sample T-test, one-way ANOVA, and Spearman correlation are used to analyze preference heterogeneity. The results show that: (1) residents prefer WP, AP, AGR, and FW; (2) 51.3% of respondents are willing to pay a fee for improving ES while 48.7% of respondents are unwilling to pay; (3) residents' personal and residential factors affect preference heterogeneity. Last, we put forward three management suggestions on controlling environmental pollution, improving residents' awareness of ES, and establishing a multi-channel fund based on government financial resources for improving ES in the Fenghe River watershed. Integrating stakeholders' perceptions for ES into decision-making can promote the sustainable development in Fenghe River watershed.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31561590

RESUMO

With the rapid expansion of impervious surfaces, urban waterlogging has become a typical "urban disease" in China, seriously hindering the sustainable development of cities. Therefore, reducing the impact of impervious surfaces on surface runoff is an effective approach to alleviate urban waterlogging. Presently, the development mode of many cities in China has shifted from an increase in urban scale to the improvement of urban quality through urban renewal, which is the current and future development path for most cities. Optimizing the design of impervious surfaces in urban renewal planning to reduce its impact on surface runoff is an important way to prevent and control urban waterlogging. The aim of this research is to construct an optimization model of impervious surface space layout under the framework of a geographic simulation technology-integrated ant colony optimization (ACO) and Soil Conservation Service curve number (SCS-CN) model (ACO-SCS) in a case study of Guangzhou in China. Urban runoff plots in the study area are divided according to the area of the urban planning unit. With the goal of minimizing the runoff coefficient, the optimal space layout of the impervious surfaces is obtained, which provides a technical method and reference for urban waterlogging prevention and control through urban renewal planning. The results reveal that the optimization of impervious surface space layout through ACO-SCS achieves a satisfactory effect with an average optimization rate of 9.52%, and a maximum optimization rate of 33.16%. The research also shows that the initial impervious surface layout is the key influencing factor in ACO-SCS. In the urban renewal planning stage, the space layout of the impervious surfaces with a high-low-high density discontinuous connection can be constructed by transforming medium-density impervious surfaces into low-density impervious surfaces to achieve the flat and long-type agglomeration of the low-density and high-density impervious surfaces, which can effectively reduce the influence of urban development on surface runoff. There is spatial heterogeneity of the optimal results in different urban runoff plots. Therefore, the policy of urban renewal planning for urban waterlogging prevention and control should be different. The optimized results of impervious surface space layout provide useful reference information for urban renewal planning.

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