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Water quality of the Grijalva river on the Chiapas - Tabasco border/ Calidad de agua del río Grijalva en la frontera de Chiapas y Tabasco
2018
Musálem-Castillejos, Karim | Laino-Guanes, Rafaela | Bello Mendoza, Ricardo | González-Espinosa, Mario | Ramírez-Marcial, Neptalí
he objective was to characterize the water quality in a section of the Grijalva River and in some of its tributaries on the border between the States of Chiapas and Tabasco, in the rainy and dry seasons. Twenty-three physical, chemical and microbiological parameters as well as contaminants were determined. The values obtained were compared with the maximum permissible limits (MPLs) for water use and human consumption set out in O cial Mexican standard NOM-127-SSA1-1994, and with the water quality classi cation scale of the Comisión Nacional del Agua (CONAGUA). The water quality in the studied section of the Grijalva River decreases as it descends to more populated areas of the State of Tabasco. Water turbidity and E. coli coliform levels increase, both in the river channels and in sources destined for human consumption. For the other variables evaluated, there are acceptable water quality characteristics, mainly in the dry season, except for mercury, which occurs at levels higher than those recommended. Further studies on the presence of mercury in the Grijalva River basin are recommended.
Afficher plus [+] Moins [-]Potassium fertilization in rocket plants: production and efficiency in water use = Adubação potássica em plantas de rúcula: produção e eficiência no uso da água
2013
Porto, Rebeca de Andrade | Bonfim-Silva, Edna Maria | Débora Santana de Matos Souza | Cordova, Norman Ruddel Mendez | Polyzel, Analy Castilho | Tonny José Araújo da Silva
The rocket (Euruca sativa) is an important vegetable in human´s feed and one of the most nutritious, rich in minerals such as potassium, sulfur and iron, and vitamins A and C. Since the late 90’s the rocket is gaining more market, with an increase in quantity sold, and its area planted. The aim for this study is to assess the effect of potassium on the yield characteristics, SPAD reading and efficiency in water use by plants of rocket. The experiment was conducted in a greenhouse during May-June 2011. The experimental plot consisted of vase built by PET 2.5 liter bottle with a capacity of 1 dm-3 of soil, using a wool wick for irrigation by capillary. The experimental design was completely randomized and its treatments consisted of six doses ofK2O: 0; 50; 100; 150; 200 and 250 mg dm-3 and using as source KCl and six replications. The variables analyzed were SPAD readings, leaf number, fresh mass, dry mass, root dry mass and water use efficiency. The potassium fertilization increases the SPAD reading and water use efficiency by rocket plants in potassium doses of 156.4 and 200 mg dm-3, respectively. Variables fresh and dry mass of plants are influenced by potassium fertilization with adjust of linear regression model. Variables number of leaves and root dry weight are not influenced by potassium fertilization.ResumoA rúcula (Euruca sativa) é uma hortaliça relevante na alimentação humana sendo uma das mais nutritivas, ricas emminerais como potássio, enxofre e ferro, além das vitaminas A e C. Desde o final da década de 90 a rúcula vem conquistandomercado com um aumento na quantidade comercializada e na sua área de plantio. Objetivou-se pelo presente estudo avaliaro efeito de doses de potássio nas características produtivas, leitura SPAD e eficiência no uso da água por plantas de rúcula.O experimento foi realizado em casa de vegetação no período de maio a junho de 2011. A parcela experimental consistiu devaso construído por garrafa PET de 2,5 litros, com capacidade para 1 dm-3 de solo, utilizando-se pavio de lã para irrigação porcapilaridade. O delineamento experimental foi inteiramente casualizado cujos tratamentos consistiram de seis doses de K2O: 0;50; 100; 150; 200 e 250 mg dm-3 utilizando-se como fonte o KCl e seis repetições. As variáveis analisadas foram leitura SPAD,número de folhas, massa fresca e massa seca da parte aérea, massa seca da raiz e eficiência no uso da água. A adubação compotássio aumenta a leitura SPAD e a eficiência no uso de água por plantas de rúcula nas doses de potássio de 156,4 e 200 mg dm-3,respectivamente. As variáveis massas fresca e seca de plantas são influenciadas pela adubação potássica com ajuste a modelolinear de regressão. As variáveis número de folhas e massa seca de raiz não são influenciadas pela adubação potássica.
Afficher plus [+] Moins [-]Multi-source water characterisation for water supply and management strategies on a small Mediterranean island | Caractérisation multi-source pour des stratégies d’approvisionnement et de gestion de l’eau sur une petite île méditerranéenne Caracterización del agua de múltiples fuentespara el suministro de agua y estrategias de gestión en una pequeña isla del Mediterráneo 地中海小岛上用于供水和管理策略的多源水特征 Caracterização da água de várias fontes para estratégias de gerenciamento e abastecimento de água em uma pequena ilha do Mediterrâneo Texte intégral
2020
Cappucci, Sergio | De Cassan, Maurizio | Grillini, Marcello | Proposito, Marco | Screpanti, Augusto
The small islands in the Mediterranean Sea suffer water shortages, aggravated by pressure from tourism during the dry season. Many are affected by the intense and increasing human water demand and the harsh climatic and geographic nature of the island terrain. The present study, carried out on the island of Favignana, Egadi Archipelago (southern Italy), evaluates the regime of recharge to the subsurface, and hypothesizes a solution for identifying the areas where groundwater is most abundant, as well as the best management options for human use. By means of hydrological measurements and chemical analyses, a specific location has been identified in the eastern sector of the island where groundwater has optimal quality and the water table is at a depth of only a few metres. In other areas of the island the groundwater is more saline, due to seawater intrusion, and it is present only at greater depths. The residents of the island have in the past lived harmoniously with the climatic and hydrological regime of the island, and have shown good ability to manage the groundwater resources, fed by the limited precipitation that comes in winter, using it as a supplement to the drinking water supply that comes from Trapani (mainland Sicily) by a submarine pipeline and by tanker. Optimized management of the groundwater resources could reduce the volume of freshwater transferred from the mainland.
Afficher plus [+] Moins [-]Tratamento de água residuária de curtume com utilização de sementes de moringa (Moringa oleifera L.). = Treatment of residuary water from tannery utilizing moringa(Moringa oleifera L.) seeds
2010
Santos, Lucas Moreira | Reis, Edson Marques dos | Silva, Frederico Fonseca | Silva, Frederico Fonseca | Zonetti, Patrícia da Costa
A partir da comprovação por vários estudos que as sementes de Moringa (Moringa oleifera L.) apresentam a capacidade de clarificar e purificar água potencialmente fora de especificações para consumo humano. Objetivou-se com o presente projeto avaliar se a semente de moringa tem capacidade de purificar água residuária de curtume. Foi utilizada água residuária bruta, coletada antes das estações de tratamento de dois curtumes no município de Maringá, Paraná. As sementes de moringa foram obtidas nos municípios de Umuarama e Floraí, Paraná. As sementes foram retiradas do fruto antes do processo de deiscência e trituradas em meio de água destilada. O sistema foi realizado em sistema descontínuo de tratamento, utilizando vasos de 25litros, onde foram utilizados 15 litros de água residuárias de curtume. Foram feitos uma testemunha e três tratamentos com a mesma concentração 8,0 g L-1 variando a fração em função do tempo de 4, 8 e 12 horas. Foram avaliados os parâmetros: pH, nitrogênio amoniacal, turbidez, DBO e DQO. Os melhores resultados obtidos foram no parâmetro nitrogênio. = The evidence from several studies have indicated that the seeds of Moringa (Moringa oleifera L.) have the ability to clarify and purify water potentially out of specification for human consumption. The objective of this project was to evaluate whether the seeds of moringa are capable of purifying wastewater from tannery. Untreated wastewater was used, collected before entering the treatment plants of two tanneries in the city of Maringá, Paraná, Brazil. The moringa seeds were collected in the municipalities of Umuarama and Floraí, Paraná, Brazil. Seeds were removed from the fruit before dehiscence and crushed within distilled water. The system was carried out in batch processing, using 25-liter pots, and 15 liters of wastewater from the tannery. One control and three treatments were used. All groups contained the same concentration 8.0 g L-1 but were done in 4, 8 and 12 hours. The following parameters were evaluated: pH, ammonia nitrogen, turbidity, BOD and COD. The best results were obtained in the parameter nitrogen.
Afficher plus [+] Moins [-]Simulation and consequences of successive anthropogenic activity in the Agua Amarga coastal aquifer (southeast Spain) Texte intégral
2013
Alhama Manteca, I.
The Agua Amarga coastal aquifer has been the object of a succession of anthropogenic interventions over the last 90 years: (a) the operation of saltworks from 1925 to 1975; (b) the withdrawal, since 2003, of groundwater from the aquifer along the coast line; and (c) the programme of pouring seawater over the salt marsh, carried out since 2009, to recover the piezometric levels and the soil moisture conditions. For a better understanding of how these past and present human activities have affected the natural groundwater regime, and to validate certain hypotheses concerning the interpretation of experimental data on temperature depth profiles and piezometric and salinity changes, a numerical fluid flow and solute transport model was designed and applied to the period 1925–2010, using SEAWAT. This model reproduces, in a qualitative and quantitative way, the flow and transport processes that operated during this time, as well as the behaviour of the seawater wedge.
Afficher plus [+] Moins [-]Caracterización espacial y estacional del agua de consumo proveniente de diversas fuentes en una localidad periurbana de Salta Texte intégral
2017
Rodriguez-Alvarez, María S. | Moraña, Liliana B. | Salusso, María M. | Seghezzo, Lucas
Drinking water monitoring plans are important to characterize both treated and untreated water used for drinking purposes. Access to drinking water increased in recent years as a response to the Millennium Development Goals set for 2015. The new Sustainable Development Goals aim to ensure universal access to safe drinking water by 2030. Within the framework of these global goals, it is crucial to monitor local drinking water systems. In this paper, treated and untreated water from different sources currently consumed in a specific town in Salta, northern Argentina, was thoroughly assessed. Monitoring extended along several seasons and included the physical, chemical and microbiological variables recommended by the Argentine Food Code. On the one hand, treated water mostly complies with these standards, with some non-compliances detected during the rainy season. Untreated water, on the other hand, never meets microbiological standards and is unfit for human consumption. Monitoring seems essential to detect anomalies and help guarantee a constant provision of safe drinking water. New treatment plants are urgently needed to expand the water grid to the entire population.
Afficher plus [+] Moins [-]Calidad del agua de la niebla captada artificialmente en la microcuenca del río pixquiac, veracruz, méxico: resultados preliminares Texte intégral
2015
Jofre-Meléndez, Rodolfo | Cervantes Pérez, Juan | Barradas, Víctor L.
In order to determine if artificially collected water fog in the mountainous located in central the region of Veracruz state is suitable for human consumption; a preliminary sampling was made, from January to March (2010), the period with more fog frequency. The objective was to analyze the physical, chemical and biological aspects concerning water quality. It was found that this water is not suitable for direct human consumption, since it contains heavy metals such as mercury, coliform organisms and high amounts of ammonia nitrogen, though it is suitable for direct use in agriculture. However, it is possible to apply a sanitation treatment for human use at a cost of 0.00341 USD L-1 not including the labor cost neither the necessary infrastructure. Various causes can lead to this water pollution are discussed and it is concluded that collected fog water is not suitable for human consumption, but it might be used for agriculture.
Afficher plus [+] Moins [-]Response of groundwater level and surface-water/groundwater interaction to climate variability: Clarence-Moreton Basin, Australia | Evolution du niveau piézométrique et des relations nappe-rivière en réponse à la variabilité climatique : bassin de Clarence-Moreton (Australie) Respuesta del nivel del agua subterránea y de la interacción agua superficial/agua subterránea a la variabilidad climática: Cuenca Clarence-Moreton, Australia 气候变化对地下水以及地表水-地下水交互的影响:澳大利亚Clarence-Moreton盆地 Resposta do nível das águas subterrâneas e interação águas superficiais/águas subterrâneas à variabilidade climática: Bacia Clarence-Moreton, Austrália Texte intégral
2018
Cui, Tao | Raiber, Matthias | Pagendam, Dan | Gilfedder, Mat | Rassam, David
Understanding the response of groundwater levels in alluvial and sedimentary basin aquifers to climatic variability and human water-resource developments is a key step in many hydrogeological investigations. This study presents an analysis of groundwater response to climate variability from 2000 to 2012 in the Queensland part of the sedimentary Clarence-Moreton Basin, Australia. It contributes to the baseline hydrogeological understanding by identifying the primary groundwater flow pattern, water-level response to climate extremes, and the resulting dynamics of surface-water/groundwater interaction. Groundwater-level measurements from thousands of bores over several decades were analysed using Kriging and nonparametric trend analysis, together with a newly developed three-dimensional geological model. Groundwater-level contours suggest that groundwater flow in the shallow aquifers shows local variations in the close vicinity of streams, notwithstanding general conformance with topographic relief. The trend analysis reveals that climate variability can be quickly reflected in the shallow aquifers of the Clarence-Moreton Basin although the alluvial aquifers have a quicker rainfall response than the sedimentary bedrock formations. The Lockyer Valley alluvium represents the most sensitively responding alluvium in the area, with the highest declining (−0.7 m/year) and ascending (2.1 m/year) Sen’s slope rates during and after the drought period, respectively. Different surface-water/groundwater interaction characteristics were observed in different catchments by studying groundwater-level fluctuations along hydrogeologic cross-sections. The findings of this study lay a foundation for future water-resource management in the study area.
Afficher plus [+] Moins [-]A late Holocene paleoenvironmental reconstruction from Agua Caliente, southern Belize, linked to regional climate variability and cultural change at the Maya polity of Uxbenká Texte intégral
2014
Walsh, Megan K. | Prufer, Keith M. | Culleton, Brendan J. | Kennett, Douglas J.
We report high-resolution macroscopic charcoal, pollen and sedimentological data for Agua Caliente, a freshwater lagoon located in southern Belize, and infer a late Holocene record of human land-use/climate interactions for the nearby prehistoric Maya center of Uxbenká. Land-use activities spanning the initial clearance of forests for agriculture through the drought-linked Maya collapse and continuing into the historic recolonization of the region are all reflected in the record. Human land alteration in association with swidden agriculture is evident early in the record during the Middle Preclassic starting ca. 2600calyrBP. Fire slowly tapered off during the Late and Terminal Classic, consistent with the gradual political demise and depopulation of the Uxbenká polity sometime between ca. 1150 and 950calyrBP, during a period of multiple droughts evident in a nearby speleothem record. Fire activity was at its lowest during the Maya Postclassic ca. 950–430calyrBP, but rose consistent with increasing recolonization of the region between ca. 430calyrBP and present. These data suggest that this environmental record provides both a proxy for 2800years of cultural change, including colonization, growth, decline, and reorganization of regional populations, and an independent confirmation of recent paleoclimate reconstructions from the same region.
Afficher plus [+] Moins [-]Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa | Prendre en compte l’utilisation des eaux souterraines pour améliorer l’évaluation des pompages d’eaux souterraines pour l’irrigation dans le Nord de l’Afrique Consideraciones del uso del agua subterránea para mejorar la evaluación del bombeo de agua subterránea para el riego en el norte de África 考虑地下水的利用情况来提高北非地区抽取地下水用于灌溉的评价水平 Considerando o uso das águas subterrâneas para melhorar a avaliação do bombeamento de água subterrânea para irrigação no Norte de África Texte intégral
2017
Massuel, Sylvain | Amichi, Farida | Ameur, Fatah | Calvez, Roger | Jenhaoui, Zakia | Bouarfa, Sami | Kuper, Marcel | Habaieb, Hamadi | Hartani, Tarik | Hammani, Ali
Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers’ knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.
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