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Effects of resource-oriented waste management on optimizing water-food-energy nexus in rural China: A material and energy flow analysis Texte intégral
2020
Xu, Mingjie | Fan, Bin | Zhang, Yu | Li, Ao | Li, Yahui | Lv, Minghuan | Shi, Yunpeng | Zhu, Shikun | Qian, Tingting
The waste management as the interface between human daily life and environment is an important part in rural region. However, the micro-scale process analysis from the perspective of an integrated rural water-food-energy system has not been well investigated to reveal the effects brought by waste management on local environment. The lack of relevant evidence is a major barrier to realize the specific quantitative impacts of distinct waste management systems and the importance of sustainable waste management for local area. In this study, a material and energy flow analysis based on processes is presented in a micro-scale to make systematical comparison between end-pipe-treatment waste management and modern resource-oriented waste management. The results indicated that waste management notably affects the nitrogen and phosphorus flow in rural areas. Moreover, the resource-oriented system can obviously optimize the local water-food-energy nexus in terms of energy recovery and nutrient consumption. Based on the quantity analysis, chemical fertilizer is also found inevitable to guarantee the food supply because of the element system loss in various paths. Besides, the simultaneous optimum point of different nutrient elements is difficult to achieve due to their distinct transfer mechanisms. Our results can help policymakers and publics make better choice in waste management strategy.
Afficher plus [+] Moins [-]The 'Water, food, energy and ecosystem Nexus’ and Migration : An explorative study of key drivers of migration flows and their impacts
2020
Rooij, de, Bertram | Tabeau, Ewa | Agricola, Herman | Soma, Katrine | Terwisscha van Scheltinga, Catharien | Kuiper, Marijke | Verma, Monika | Stuiver, Marian
Determination of 2,4-Dichlorophenoxyacetic acid in food and water samples using a modified graphene oxide sorbent and high-performance liquid chromatography Texte intégral
2020
Mohammadnia, Maryam | Heydari, Rouhollah | Sohrabi, Mahmoud Reza
In the present work, dispersive micro-solid phase extraction (D-μ-SPE) method using magnetic graphene oxide tert-butylamine (GO/Fe₃O₄/TBA) nanocomposite, as an efficient sorbent, was applied for determining 2,4-dichlorophenoxyacetic acid (2,4-D) in water and food samples. Detection was carried out using high-performance liquid chromatography (HPLC) instrument. Influential parameters of D-μ-SPE such as sorbent and its amount, elution solvent and its volume, adsorption and desorption times and pH of sample solution were investigated and optimized. Under the optimized conditions, limit of detection and quantitation values were 0.007 and 0.02 μg/mL, respectively. Recovery data for several real samples were obtained within the range of 88.0–94.0% with a relative standard deviation (RSD) less than 7.5%. The proposed method was successfully applied to quantitative determination of 2,4-D in several vegetables and water samples.
Afficher plus [+] Moins [-]Stable isotope ratios of emergent adult aquatic insects can be used as indicators of water pollution in the hyporheic food web Texte intégral
2020
Alam, Md Khorshed | Negishi, Junjiro N. | Rahman, Mirza A.T.M Tanvir | Rodulfo Tolod, Janine
Bio-assessment protocols for the subsurface domain of river channels (i.e. hyporheic zone) are scarce despite of the known importance of its ecological function in river ecosystems. The larvae of the Alloperla ishikariana Plecoptera species inhabit the hyporheic zone. Therefore, we examined whether emergent adult A. ishikariana could serve as proxy indicators of the effects of pollution in the hyporheic food web. The study site comprised a 15-km stretch of a gravel bed river in Hokkaido, Japan, from which all invertebrates were collected from the riverbed at a depth of 30–50 cm, and emergent A. ishikariana adults were sampled in riparian zones. Water quality changed gradually along the river owing to the effects of a wastewater treatment plant and surrounding land uses. Nitrogen and carbon stable isotope ratios (SIRs) of epilithic biofilms, hyporheic particulate organic matter (POM), benthic POM, and invertebrates were used to determine the major basal carbon sources, the effects of water pollution on the hyporheic zone, and the trophic positions of dominant invertebrates. Generalized linear (mixed) models were used for statistical testing and modeling. Amphipoda and the larvae of A. ishikariana were considered as top predators and secondary consumers in the hyporheic food web, respectively. The observed similarity in water quality between the hyporheic and surface water suggested a large degree of hydrological exchange between the two zones, and resulted in positive increases in the nitrogen SIRs of hyporheic invertebrates, including A. ishikariana larvae, in proportion to nitrate levels in the surface water. The nitrogen SIRs of A. ishikariana adults were significantly correlated with the nitrogen SIRs of their larvae within the same location (adjusted R² = 0.78), indicating that emerged adults can provide information on the longitudinal variability of the effects of synthetic nitrogen. In contrast, the carbon SIRs of adults did not predict those of their larvae, possibly reflecting the diverse feeding habitats of larvae. Overall, we demonstrated that adult aquatic insects emerging from the hyporheic zone can be used as indirect indicators of pollution-associated nutrient assimilation as well as the spatial heterogeneity of dietary carbon resources in hyporheic food web.
Afficher plus [+] Moins [-]Disparate on-site access to water, sanitation, and food storage heighten the risk of COVID-19 spread in Sub-Saharan Africa Texte intégral
2020
Ekumah, Bernard | Armah, Frederick Ato | Yawson, David Oscar | Quansah, Reginald | Nyieku, Florence Esi | Owusu, Samuel Asiedu | Odoi, Justice Odoiquaye | Afitiri, Abdul-Rahaman
COVID-19 is an active pandemic that likely poses an existential threat to humanity. Frequent handwashing, social distancing, and partial or total lockdowns are among the suite of measures prescribed by the World Health Organization (WHO) and being implemented across the world to contain the pandemic. However, existing inequalities in access to certain basic necessities of life (water, sanitation facility, and food storage) create layered vulnerabilities to COVID-19 and can render the preventive measures ineffective or simply counterproductive. We hypothesized that individuals in households without any of the named basic necessities of life are more likely to violate the preventive (especially lockdown) measures and thereby increase the risk of infection or aid the spread of COVID-19. Based on nationally-representative data for 25 sub-Saharan African (SSA) countries, multivariate statistical and geospatial analyses were used to investigate whether, and to what extent, household family structure is associated with in-house access to basic needs which, in turn, could reflect on a higher risk of COVID-19 infection. The results indicate that approximately 46% of the sampled households in these countries (except South Africa) did not have in-house access to any of the three basic needs and about 8% had access to all the three basic needs. Five countries had less than 2% of their households with in-house access to all three basic needs. Ten countries had over 50% of their households with no in-house access to all the three basic needs. There is a social gradient in in-house access between the rich and the poor, urban and rural richest, male- and female-headed households, among others. We conclude that SSA governments would need to infuse innovative gender- and age-sensitive support services (such as water supply, portable sanitation) to augment the preventive measures prescribed by the WHO. Short-, medium- and long-term interventions within and across countries should necessarily address the upstream, midstream and downstream determinants of in-house access and the full spectrum of layers of inequalities including individual, interpersonal, institutional, and population levels.
Afficher plus [+] Moins [-]Water energy food nexus approach for sustainability assessment at farm level: An experience from an intensive agricultural area in central Italy Texte intégral
2020
Fabiani, Stefano | Vanino, Silvia | Napoli, Rosario | Nino, Pasquale
Sustainable management of natural resources under economic, environmental and social perspective, needs to consider a fair balance between its uses and availability. Sustainable agriculture goal is to establish innovative and new farm tools and service capacities that help the intensive farm sector to optimize input management (energy, nutrients and water) and productivity. The main objective of this paper was to investigate, in a durum wheat production system in central Italy under Mediterranean conditions, the following aspects: (i) environmental sustainability of fertilization treatments through the energy inputs/outputs analysis and reduction of Nitrate (N-NO₃) in water cycle; (ii) agricultural system agronomic and economic performance and (iii) to identify regulatory and economic instruments actually in place to promote sustainable fertilization. To describe and address the sustainability assessment of durum wheat production system we adopt the “Water Energy Food nexus” (WEF) as conceptual framework. The findings of this research showed that there is a great difference between the marketable yields obtained with mineral fertilization strategies and those by organic fertilizer, while considering the environmental sustainability, our results provide evidences of the significance of the reduction of energy use and the high value of renewable energies and the decreasing of non-renewable one. At the same time the reduced impact of groundwater quality due to the organic fertilizer seems to be an interesting result to be analyzed in the long-term perspective. The contraposition between economy and environment is one of the main challenges to be solved through adequate policy instruments.
Afficher plus [+] Moins [-]Water and Food restriction decreases immunoreactivity of oestrogen receptor alpha and antioxidant activity in testes of sexually mature Coturnix coturnix japonica Texte intégral
2020
Baghel, Kalpana | Niranjan, Mukesh K. | Srivastava, Rashmi
Food and water are closely associated with reproductive willingness in vertebrates. These are important for animals and their non‐availability act as stressors which decrease sex steroid secretion suppressing reproductive behaviour. Oestrogen plays a crucial role in reproduction via its receptors alpha (ERα) and beta (ERβ). This study tested the hypothesis that ERα in testes of male Japanese quail is regulated during water and food deprivations. The present study reveals that both water and food deprivations cause oxidative stress and subsequently decrease catalase and superoxide dismutase activity, while these increase malondialdehyde and hydrogen peroxide. Both deprivations reduce plasma oestradiol whereas elevate corticosterone level. The immunofluorescent localization of ERα in the testes occurs predominantly in the seminiferous tubules of control while reduces after both food and water deprivations. All types of spermatogenic cells were seen in control testis, while after water and food deprivations size of seminiferous tubules and spermatogenic cells population decreased. Scanning electron microscopic study exhibited fully mature sperms in clusters with head and elongated flagellum, whereas after water deprivation maximum sperms were distorted, scattered with highly reduced head. On food deprivation, only few sperms were seen with head and tail. Thus, taking into account the localization of ERα in testis, it is obvious that oestrogens produced locally are involved in regulation of spermatogenesis and spermiogenesis during stress.
Afficher plus [+] Moins [-]Impact of water column stability dynamics on the succession of plankton food web types in the offshore area of the Adriatic Sea Texte intégral
2020
Šolić, Mladen | Šantić, Danijela | Šestanović, Stefanija | Bojanić, Natalia | Grbec, Branka | Jozić, Slaven | Vrdoljak, Ana | Ordulj, Marin | Matić, Frano | Kušpilić, Grozdan | Gladan, Živana Ninčević
Vertical mixing and stratification are among the most important physical processes controlling nutrient dynamics, the dominant category of primary producers and consequently the dominant types of food web, and are therefore important for the assessment of the marine ecosystem's response to global climate change. This study showed consistent short-term cyclic successions of the plankton food web types, governed by the dynamics of water column stability changes, occurring in generally oligotrophic, phosphate deficient surface waters of the open middle Adriatic Sea. The biogeochemical nitrogen cycle appeared as a key driving force responsible for the food web structure changes. The ‘herbivorous food web’ dominated during the nitrate-rich mixed water column period (winter) and gradually changed to ‘multivorous food web’ where large phytoplankton still constitute a significant fraction of phytoplankton. This intermediate type of food web lasted for a short time and quickly changed to the typical ‘microbial food web’, which then dominated during the stratified water column period (summer) and was characterised by a large proportion of picoplankton size-fraction organisms in total plankton biomass and production. Furthermore, at the very end of summer, the high bacterial carbon flux through the ‘microbial loop’ was established. The succession of food web types affects the mechanisms of bacterial control in a way that ‘bottom up’ control dominated during the mixed water column period and ‘top-down’ control prevailed during the stratified period. Since the ongoing global warming is expected to change water column stability dynamics and thereby significantly affect the supply of nutrients in surface waters, this study helps to understand the possible direction of changes in the plankton food webs of the Adriatic Sea, and consequent changes in marine nitrogen and carbon biogeochemical cycles.
Afficher plus [+] Moins [-]Exploring synergies in the water-food-energy nexus by using an integrated hydro-economic optimization model for the Lancang-Mekong River basin Texte intégral
2020
Do, Pierre | Tian, Fuqiang | Zhu, Tingju | Zohidov, Bahtiyor | Ni, Guangheng | Lu, Hui | Liu, Hui
The Water-Food-Energy nexus study identifies developmental challenges and trade-offs present along the transboundary river basins. Intensive reservoir development for hydropower production impacts existing actors in the Lancang-Mekong River Basin. Concerns from these stakeholders highlight three major trade-offs that occur between hydropower and irrigation (HP-AG), hydropower and fisheries (HP-F), and irrigation and fisheries (AG-F). Dam construction has an impact not only on power production but also on ecosystems and ultimately the livelihood of people. In this study, we quantify the effects of reservoir operation on hydropower generation, irrigated crop production and fisheries yield in the Tonle Sap lake through a novel hydro-economic model at the whole basin scale. Our main finding is that trade-offs can be turned into synergetic opportunities. First, the dam operation can increase water availability for irrigation without severely harming hydropower production, raising irrigated crop revenue by 49% and reducing crop losses during droughts by 30%. Second, eco-friendly management increases fisheries yield by up to 75%, but decreases both irrigated crop production (−48%) and power production (−17%). Reservoirs can, therefore, benefit the whole basin by releasing more water in months with high irrigation demand (April and December) and by minimizing the adverse effects of flow fluctuations on the livelihood of farmers and fishers living downstream. Our results also reveal the overlooked trade-off between irrigated agriculture and fisheries. Cross-sectoral and transboundary partnerships should strengthen stakeholder participation in decision-making. Local solutions such as enhanced reservoir operation can respond to the broader global issue of natural resource trade-offs and sharing. Our alternative narrative enhances the dialogue about fair and efficient water use among Mekong riparian countries.
Afficher plus [+] Moins [-]Prenatal and childhood arsenic exposure through drinking water and food and cognitive abilities at 10 years of age: A prospective cohort study Texte intégral
2020
Vahter, Marie | Skröder, Helena | Rahman, Syed Moshfiqur | Levi, Michael | Derakhshani Hamadani, Jena | Kippler, Maria
Our studies of children in a rural Bangladeshi area, with varying concentrations of arsenic in well-water, indicated modest impact on child verbal cognitive function at 5 years of age.Follow-up of arsenic exposure and children’s cognitive abilities at school-age.In a nested sub-cohort of the MINIMat supplementation trial, we assessed cognitive abilities at 10 years of age (n = 1523), using Wechsler Intelligence Scale for Children (WISC-IV). Arsenic in maternal urine and erythrocytes in early pregnancy, in child urine at 5 and 10 years, and in hair at 10 years, was measured using Inductively Coupled Plasma Mass Spectrometry.Median urinary arsenic at 10 years was 58 µg/L (range 7.3–940 µg/L). Multivariable-adjusted regression analysis showed that, compared to the first urinary arsenic quintile at 10 years (<30 µg/L), the third and fourth quintiles (30–45 and 46–73 µg/L, respectively) had 6–7 points lower Full developmental raw scores (B: −7.23, 95% CI −11.3; −3.18, and B: −6.37, 95% CI −10.5; −2.22, respectively), corresponding to ~0.2 SD. Verbal comprehension and Perceptual reasoning seemed to be affected. Models with children’s hair arsenic concentrations showed similar results. Maternal urinary arsenic in early pregnancy, but not late pregnancy, showed inverse associations with Full developmental scores (quintiles 2–4: B: −4.52, 95% CI −8.61; −0.43, B: −5.91, 95% CI −10.0; −1.77, and B: −5.98, 95%CI −10.2; −1.77, respectively, compared to first quintile), as well as with Verbal comprehension, Perceptual reasoning, and Processing speed, especially in girls (p < 0.05 for interaction of sex with Full developmental scores and Perceptual reasoning). In models with all exposure time points included, both concurrent exposure at 10 years and early prenatal exposure remained associated with cognitive abilities.Both early prenatal and childhood arsenic exposure, even at low levels (about 50 µg/L in urine), was inversely associated with cognitive abilities at school-age, although the estimates were modest.
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