Hasil untuk "River, lake, and water-supply engineering (General)"

João da Silva Cavalcante, Iran Eduardo Lima Neto

ABSTRACT The Maceió Stream watershed, in Fortaleza, Ceará, Brazil, plays a vital role in the city’s urban drainage system but suffers from urbanization, pollution, and environmental degradation. This study applies the Storm Water Management Model (SWMM) to develop hydrological-hydraulic and water quality models, assessing the impacts of impervious areas and diffuse pollution. The integrated model simulates flow rates, flood peaks, and pollutant concentrations, focusing on Biochemical Oxygen Demand (BOD), Total Nitrogen (TN), Total Phosphorus (TP), and Escherichia coli (E. coli). The watershed’s relevance stems from its location across densely populated and socially vulnerable areas, making its management environmentally and socially critical. Model performance showed good reproduction of Maceió Stream hydrographs (NSE = 0.78, PBIAS = -9%), with excellent accuracy for BOD (NSE = 0.97, PBIAS = 2%), TN (NSE = 0.91, PBIAS = -3%), and TP (NSE = 0.98, PBIAS = -4%). Scenario analyses considering climate change and continued urbanization revealed the necessity of drainage interventions to mitigate extreme hydrological events and strategies to improve water quality. The study concludes that integrated modeling with SWMM is an effective tool for diagnosing water-related challenges and guiding sustainable management solutions for urban watersheds.

Sergei A. Miroshnichenko, Anton I. Luchnikov, Sergei A. Lepeshkin et al.

Settlements located in the floodplain of the Vaga River (in the middle and lower reaches) are periodically flooded during the passage of the spring flood. As a result, of flooding, serious material damage is caused to residential buildings and economic facilities, and people’s lives are at serious risk.

JIANG Shuihua, CHEN Yingxia, XIONG Wei et al.

Dike is an important facility to prevent flood disasters in the area of lakes and plain rivers. There are lots of serious loss consequences when dike engineering is in danger and causes destruction. Therefore, risk assessment, as well as management and control of dike engineering danger have been given great importance all over the world. However, the uncertain factors such as dike material properties, earthquakes, and extremely heavy rainfall in dike engineering systems are not quantitatively characterized insufficiently, and the understanding of occurrence environments where dike engineering danger exists is not clear. As a result, the mechanism and evolution process of dike engineering danger are not clarified. Besides, the risk assessment methods of dike engineering danger are still mainly semi-qualitative and semi-quantitative, lacking corresponding comprehensive quantitative assessment methods and measuring standards for the consequences of dike engineering danger, resulting in poor effect of risk management and control measures for dike engineering danger. In view of this, the literature and field investigation were conducted in five aspects: identification and characterization of the occurrence environment for dike engineering danger, disaster mechanism and evolution processes of dike engineering danger, consequence analysis of dike engineering danger, risk assessment of dike engineering danger, and risk management and control of dike engineering danger. Then, the overseas and Chinese research and existing problems in the above five aspects were summarized. Furthermore, the prospective key research contents of risk assessment, as well as management and control of dike engineering danger were concluded. The research results are expected to provide important ideas and theoretical support for scientifically revealing the disaster mechanism of dike engineering danger, putting forward a practical quantitative risk assessment method for dike engineering danger, and constructing a risk-based informatization and standardized information management and control system for dike engineering.

WANG Siwei, ZANG Caixia, BAO Pengwei

Xavier Garcia

Abstract Modeling tools simulate the functioning of ecosystems and their interactions with human activities, helping decision makers understand how interventions impact ecosystems and evaluate management strategies. This leads to informed decisions that balance human development and environmental protection. Among these models, Soil and Water Assessment Tool (SWAT) stands out for its ability to simulate multiple biophysical processes that can be linked to the provision of ecosystem services (ES). Although SWAT has been successfully applied for the evaluation of ES, the development of complementary approaches that translate the results of SWAT into monetary terms is still in its early stages. To narrow this gap, this review article aims to provide a comprehensive assessment of the literature on the relationship between SWAT model results and economic analysis. Specifically, the review summarizes the research conducted on the use of SWAT model results to estimate economic values, including the different methodologies used and the types of economic values estimated. The review will also discuss the limitations and challenges of these approaches, provide a critical evaluation of the strengths and weaknesses of the research in this area, and provide recommendations to strengthen SWAT application for the economic evaluation of management strategies.

Fadi Alakhras, Emna Selmane Bel Hadj Hmida, Ioannis Anastopoulos et al.

In this study, the removal of monovalent and divalent cations, Na+, K+, Mg2+, and Ca2+, in a diluted solution from Chott-El Jerid Lake, Tunisia, was investigated with the electrodialysis technique. The process was tested using two cation-exchange membranes: sulfonated polyether sulfone cross-linked with 10% hexamethylenediamine (HEXCl) and sulfonated polyether sulfone grafted with octylamine (S-PESOS). The commercially available membrane Nafion® was used for comparison. The results showed that Nafion® and S-PESOS membranes had similar removal behaviors, and the investigated cations were ranked in the following descending order in terms of their demineralization rates: Na+ > Ca2+ > Mg2+ > K+. Divalent cations were more effectively removed by HEXCl than by monovalent cations. The plots based on the Weber–Morris model showed a strong linearity. This reveals that intra-particle diffusion was not the removal rate-determining step, and the removal process was controlled by two or more concurrent mechanisms. The Boyd plots did not pass through their origin, and the sole controlling step was determined by film-diffusion resistance, especially after a long period of electrodialysis. Additionally, a semi-empirical model was established to simulate the temporal variation of the treatment process, and the physical significance and values of model parameters were compared for the three membranes. The findings of this study indicate that HEXCl and S-PESOS membranes can be efficiently utilized for water softening, especially when effluents are highly loaded with calcium and magnesium ions.

Marila Lázaro, Isabel Bortagaray, Micaela Trimble et al.

As part of the formulation of the first National Water Plan (NWP) in Uruguay, a mini-public process called ‘Citizen Deliberation on Water (Deci Agua)’ was developed in 2016. While the draft of the plan was being discussed in the formal arenas of water governance (Basin Commissions and Regional Water Resources Councils), a University research team (led by the authors), in coordination with the national water authority, adapted the mechanism of consensus conferences in order to incorporate the citizens’ visions and to contribute to public understanding of the NWP challenges. This article analyses the main aspects of the developed participation strategy and discusses them regarding a set of quality criteria used to evaluate deliberative processes. Although the final version of the NWP (passed by decree in 2017) incorporated some of the contributions of the Citizen Panel, an in-depth analysis of the scope of the deliberative process of Deci Agua allows us to delve into some key aspects related to the quality of participation processes and the challenges. A mixed approach that combines stakeholder participation and lay citizens is novel and desirable in water governance since it increases the scope of participation, deepens the legitimacy of decision-making and improves the public debate. Highlights Deci Agua was a citizen deliberation process based on consensus conferences.; A Citizen Panel contributed to the formulation of Uruguay's first National Water Plan.; The inclusion of the ethical dimension of water management was the main contribution.; Mini-publics like Deci Agua collaborate with the public debate.; Processes of citizen participation can complement stakeholder participation forums.;

Satoshi Nakai, Asmit Das, Yuya Maeda et al.

Thraustochytrids such as Aurantiochytrium are heterotrophic and produce valuable fatty acids (FAs) and therefore expected as a tool for removal of organic compounds in wastewater and simultaneous production of FAs. The four strains of Aurantiochytrium sp. were isolated from the mangrove leaf samples, and among these the strain L3W showed the high specific growth rate of 0.27 1/h at 25°C. In addition, this strain grew at the ranges of temperature from 15°C to 35°C, pH from 3 to 9, and salinity from 0.3 to 70 PSU. Under the optimal condition of 25°C, 30 PSU, and pH7, the strain L3W produced 270 mg/g of FAs including 135 mg/g of docosahexaenoic acid, 11 mg/g of pentadecanoic acid and 9.3 mg/g of margaric acid. Furthermore, the strain L3W produced these FAs at pH3 and pH9. The pH and salinity tolerance of the strain L3W might be advantageous in its application for production of valuable FAs under competition with other microorganisms in unsterile wastewater.

Filipe Viezzer da Silva, Débora Toledo Ramos, Cristina Cardoso Nunes et al.

The constant threats to ecosystem services posed by anthropogenic activities have been managed by contaminated-sites policies. Ecological Risk Assessment (ERA) has been extensively used for the environmental management of contaminated sites, especially through the international approaches - ERAGS and TRIAD. In Brazil, CONAMA 420/2009 suggests the use of ERA, but only the state norms DD 38/2017 (CETESB) and IN 74/2018 (IMA-SC) present guidelines for its execution. The purpose of this review paper was to assess the applicability of these guidelines relative to the ERAGS and TRIAD approaches, as well as to evaluate the existing standard procedures for ecotoxicological and ecological testing required by ERAs of contaminated soils. Accordingly, a review of the international ERA guidelines was conducted to assess the applicability of these methodologies in the Brazilian context, and an assessment of 42 ecological risk assessments that followed ERAGS and TRIAD approaches was used to identify the frequently performed tests and compare them to the Brazilian standard testing panorama. Overall, the current limitations identified were (i) the considerably shallowness of state guidelines; (ii) lack of laboratory infrastructure to perform the tests, which underlines (iii) the need for a national standard guideline that can thoroughly describe the ERA procedures to enable its execution and thereby, effectively promote the protection of ecosystem services.

Mrad Dounia, Djebbar Yassine, Hammar Yahia

The climatic change is a reality largely recognized today in the scientific community. Nevertheless, its impact on precipitation, especially on annual, monthly and seasonally rainfall in arid and semi-arid regions is not yet certain. Indeed, very few studies have dealt with this matter in Algeria.

Jun Shao, Jun Wang, Sunyun Lv et al.

Based on the precipitation data of 21 meteorological stations in Poyang Lake basin, the temporal and spatial variability of seasonal precipitation was analyzed by wavelet analysis method. This study adopted the cross wavelet transform to analyze the correlation between the seasonal precipitation and climate indices in time and frequency scales, discussed the possible links between its precipitation variations and climate indices, and preliminarily analyzed its mechanism and regular pattern of variation. The results showed that the oscillations in 2–4 years' and 4–8 years' bands were the main variation periods of seasonal precipitation in Poyang Lake basin. In the 2–4 years' band, the years of rainfall peaks appearing in Poyang Lake were basically consistent with the years when El Niño appeared, and the precipitation oscillations in summer appeared more dramatic in space. According to analysis on the cross wavelet power spectra between different seasonal rainfalls and climate indices, certain correlations between climate factors and seasonal precipitation had existed in specific time periods. Large-scale climate oscillations like the El Niño/Southern Oscillation, North Atlantic Oscillation, Indian Ocean Dipole, and Pacific Decadal Oscillation caused the variability of large-scale circulations through their respective independent or inter-coupled climate systems, and affected the precipitation distribution in Poyang Lake basin by changing local climate conditions like the East Asian Monsoon.

Aldria Diana Belini, Daiane Cristina de Freitas, Márcia Aparecida de Oliveira Seco et al.

O principal objetivo desse trabalho foi avaliar a qualidade de água de poços em uma área distrital do município de Campo Mourão. Neste estudo foram realizadas atividades de campo, com a identificação de pontos utilizados como fontes de abastecimento de água, através da determinação das coordenadas geográficas, utilizando o GPS (Global Position Sistem). Foram determinados os parâmetros físico-químicos de pH, turbidez, dureza, temperatura, cor e condutividade elétrica de acordo com metodologias descritas por Eaton et al. (2005); e os parâmetros microbiológicos coliformes totais e termotolerantes pela metodologia de tubos múltiplos. Os resultados obtidos demonstraram que 30% e 10% das amostras em termos de pH e turbidez, respectivamente, não atenderam os padrões de potabilidade estabelecidos pela Portaria no. 518/2004 do Ministério da Saúde. Foi também detectada presença de coliformes totais em 50% das amostras e de coliformes fecais em 25% das amostras; e que apenas os resultados obtidos para dureza e condutividade elétrica atenderam os padrões exigidos. Esses valores podem ser explicados pela caracterização do entorno que aponta fontes de poluição difusas e pontuais, dessa forma é possível concluir que muitos destes usuários estão consumindo água sem qualidade para consumo.

Sabrina M. Regattieri, Marcos Ceccato, Reginaldo A. Bertolo

O cobalto tem sido frequentemente detectado em água subterrânea de aquíferos supostamente não-contaminados em concentrações mais elevadas que o padrão ambiental vigente no Estado de São Paulo (5 μg/L), o que vem gerando suspeitas de que erros analíticos pudessem ser as principais razões para estas ocorrências. Os resultados do estudo realizado apontam que este problema deve ocorrer por conta da associação dos seguintes fatores: (1) o valor do padrão ambiental para cobalto é restritivo em comparação com outros padrões; (2) a técnica analítica de metais por ICP-MS oferece baixos valores de limites de quantificação e que seguramente são compatíveis com este padrão ambiental; e (3) o cobalto frequentemente detectado acima dos padrões (poucos ppbs) pode ter origem natural ou ligada a alterações nas condições geoquímicas naturais do aquífero devido à ação humana. O metal tem forte ligação geoquímica com o manganês, exibindo correlação positiva de concentrações, tanto em solo como em água.

YANG Jingchang

Tao Wang, Wei-min Bao, Hai-li Xu et al.

Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and relative humidity, and vary significantly with these atmospheric factors over the course of a day. The evaporation rate (E) can reveal the effects of atmospheric factors. Therefore, there should be a certain functional relationship between isotopic fractionation factors and E. An average isotopic fractionation factor (α*) was defined to describe isotopic differences between vapor and liquid phases in evaporation with time intervals of days. The relationship between α* and E based on the isotopic mass balance was investigated through an evaporation pan experiment with no inflow. The experimental results showed that the isotopic compositions of residual water were more enriched with time; α* was affected by air temperature, relative humidity, and other atmospheric factors, and had a strong functional relation with E. The values of α* can be easily calculated with the known values of E, the initial volume of water in the pan, and isotopic compositions of residual water.

GU Gui-hua

José Eduardo Campos, José Luiz Albuquerque Filho, Geraldo Hideo Oda et al.

O projeto da Carta Hidrogeológica do Estado de São Paulo tem por objetivo a representação cartográfica dos resultados obtidos nos “Estudos de Águas Subterrâneas” desenvolvidos pelo Departamento de Águas e Energia Elétrica – DAEE entre 1972 e 1982. Através de uma cooperação técnica entre o DAEE, IG/SMA, CPRM e IPT pretendese concluí-lo em 2.000, com alguma atualização e adaptação em relação à sua concepção original. No presente trabalho busca-se ilustrar parte das atividades desenvolvidas, por meio de dois mapas temáticos referentes ao Sistema Aqüífero Bauru que se estende por 100.000 km2 na porção oeste do estado de São Paulo. O Mapa do Contorno Estrutural do Topo da Formação Serra Geral (base do Bauru) elaborado a partir de mais de 500 poços é apresentado procurando-se adaptar a superfície gerada às feições tectônicas/alinhamentos estruturais, originadas pela Reativação Wealdeniana ou Sul-Atlantiana. O Mapa da Superfície Potenciométrica, obtido a partir de mais de 800 poços, permitiu verificar e confirmar o padrão de drenagem e respectivas direções de fluxos subterrâneos já identificadas pelo DAEE para a região de Presidente Prudente e Marília, em 1979.

José Carlos da Silva, Waldir Duarte Costa Filho, João Alfredo Lima Neves

A CPRM – Serviço Geológico do Brasil desenvolve, no Nordeste brasileiro, em parceria com o governo canadense, um programa de trabalho visando à otimização de metodologias de prospecção de água subterrânea em rochas cristalinas. Entre as tecnologias em desenvolvimento destaca-se o fraturamento hidráulico, executado em poços de baixa produtividade com objetivo de aumentar, em volta dos poços, os espaços para armazenamento de água. Esta alteração na geometria do reservatório é possível devido à ruptura da rocha, que ocorre quando submetida a um diferencial de pressão, aplicado dentro do poço através do bombeamento de um fluído de fraturamento. A abertura das fraturas pode provocar a interligação de sistemas de fraturas pertencentes a condutores hidráulicos diferentes, podendo ou não se constatar um incremento na capacidade de produção do poço. Em qualquer situação criam-se condições favoráveis para realização de recarga artificial, onde água de chuva coletada na superfície, através dos meios mais convenientes para cada área, pode ser armazenada para posterior recuperação, livre da evaporação e de contaminações. A expectativa, baseada em experimentos similares, é que com a execução da programação proposta, seja obtido um aumento de produtividade em cerca de 70% dos poços fraturados e que processos de recarga artificial sejam sempre adotados.