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The methodology applied for the development of the research process is framed in a conceptual basis associated with the systemic approach of the territory and the landscape units as a tool for their multiscale planning; and the municipal territorial diagnosis that allowed evidencing the potentialities and land and use conflicts associated with the construction and operational- ization of the multipurpose reservoir Topocoro. As a result, a series of strategic guidelines for sustainable development is obtained that serves as the basis for the structuring of a sustainable land management model that allows to organize the municipality of Betulia in macro units and landscape units focused on configuring plot units on sites that do not mainly affect biotic and abiotic mass, contribute to economic reactivation and the improvement of the living conditions of local communities. [ABSTRACT FROM AUTHOR]

The best technological alternative known so far to reduce emissions into the atmosphere of the largest greenhouse gas, carbon dioxide, in the short and medium term, is the capture, utilization and geological storage of CO2 (CCUS). This aspect allows the continued use of fossil fuels while moving towards the massive and comprehensive development of renewable energies. Achieving a significant reduction in CO2 emissions requires knowledge of the available CO2 storage capacity. This research shows a methodology for calculating the geological storage capacity in the part of the porous volume previously occupied by hydrocarbons can be occupied by an equivalent volume of CO2 at reservoir pressure and temperature conditions. The proposed calculation methodology (UCCGCO2) has an estimation efficiency between 90 and 98% was determined to the values obtained currently available methodologies, and its use is simpler than these. [ABSTRACT FROM AUTHOR]

Copyright of Comunicación is the property of Universidad Pontificia Bolivariana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Kavilando is the property of Kavilando and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Computer models are broadly used to simulate the hydrodynamic characteristics and water quality patterns under various conditions in reservoirs. The accuracy and reliability of model simulations often depend on the input parameter estimation and the availability of observed data. In this study, the two-dimensional hydrodynamic and water quality CEQUAL-W2 (W2) model was used to simulate the water quality and density current patterns in the Fei-Tsui Reservoir in Taiwan. The model was calibrated and validated with a 3-year dataset of reservoir water level and water quality data at different depths of the reservoir. Plots and statistical measures between simulated versus observed results demonstrated that the W2 model can accurately simulate both spatial and temporal profiles of water quality parameters in a deep subtropical reservoir. The water quality coefficient values obtained from the model calibration and verification in this study are smaller than the values reported for similar reservoirs. The W2 model calibrated using the high-frequency dataset performs better in the water quality simulation. The occurrence of different types of density currents suggested that the water temperature distribution in the water column played an important role in the pattern of turbid runoff. The W2 model is recommended to be further used to evaluate future management strategies related to eutrophication control. [ABSTRACT FROM AUTHOR]

Identifying and understanding the effects of climate change is critical to formulating optimal adaptation and mitigation measures. One of the priority issues for socioeconomic development is energy stability; however, some sources, such as hydroelectricity, are vulnerable to this phenomenon. Therefore, the main objective of the research is to identify the climatic variations that climate change could generate, with special emphasis on precipitation, in the hydroelectric production area of Arenal reservoir, Costa Rica. The materials used include historical records of meteorological stations with a base period from 1971 to 2000, as well as modeled and downscaled series from the MRI-CGCM3 model, for the Central American zone, in two scenarios of increasing radiative forcing (RCP 4.5 and RCP 8.5) with future horizon to 2100. Climatic variability was established by the calculation of climatic indices defined by the ETCCDI: simple precipitation intensity index, annual count of days when PRCP = 1 mm, maximum duration of the dry spell, maximum duration of the period of rainfall and total annual precipitation on wet days. The main findings of the research show evidence of alterations in the intensity and frequency of precipitation in the study area, mainly associated with decreases of medium magnitude in the amount of annual precipitation and the count of wet days, while there would be increases in the maximum length of dry spell, which is an unfavorable scenario for hydroelectric production and for other economic activities. In general, the indices that present significant variations are characterized by effects of medium magnitude compared to historical data, although indices such as PRCPTOT, SDII and CDD would present changes with a large effect, mainly between the medium and distant future, with the Tilarán area being the most affected, compared to the area of La Fortuna. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería del Agua is the property of Universidad Politecnica de Valencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the Magdalena River basin, fish rescue activities are an environmental management measure used to reduce fish mortality in the area near the reservoirs. When the opening and subsequent closing of the spillway gates is carried out as a result of the operation of the Porce III hydroelectric plant, downstream of the dam temporary aquatic habitats are created in the form of minor pools in the bedrock, where fish entrapment occurs. The objective of rescue activities is to relocate them to the main channel of the river, to reduce mortality. Between the years 2013 to 2020, a total of 4927 individuals were captured, representing 28 species, 12 families and five orders. We relocated 4704 individuals back to the Porce river, being the species of the genera Chaetostoma, Andinoacara, Astyanax and Rhamdia the highest capture. Potamodromous species of the family Prochilodontidae were also captured, their presence close to the dam possibly being due to the migrations they make to carry out their reproduction. These rescue and relocation actions resulting from the operation of hydroelectric plants should be replicated in the basin, as a strategy to mitigate the environmental impacts caused by habitat fragmentation. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This chapter analyzes space-time variations of phytoplankton in the limnetic zone of the Escaba reservoir and the mouths of its tributary rivers, Chavarría, Las Moras, El Chorro and Singuil, considering physicochemical variables in order to characterize the water quality between 2010 and 2012. One hundred and thirty-five taxa were determined: 77 diatoms, 35 chlorophytes, 12 cyanobacteria, 5 charophytes, 5 euglenoids and 1 dinoflagellate. Algal density varied between 84 and 6,924 individuals/ml with Ceratium hirundinella as the dominant species, except for the spring of 2011. Chlorophyll-a varied seasonally and in space with values between 6 and 2,511 µg/l, with higher numbers for the affluents. Elevated biomass values and the polysaprobic character of the waters defined a deficient or bad ecological status. The specific diversity oscillated between 0 and 2.76. The present study provides new information regarding the algal biodiversity of the Escaba dam and the distribution area of C. hirundinella in the province of Tucumán. [ABSTRACT FROM AUTHOR]

The Escaba reservoir is located in Juan Bautista Alberdi Department in the Yungas of Tucumán at about 650 meters above mean sea level. It covers an area of approximately 541 ha, with a storage capacity of 138 hm3. The reservoir is part of the Marapa-San Francisco basin shared between the provinces of Catamarca and Tucumán. Its tributaries are the permanent rivers Chavarría and Singuil together with El Chorro, Las Moras and Huasarroyo, which are rivers with less discharge. It was built in 1943 for multiple purposes including flood attenuation, regulation of flows for irrigation, recreation and tourism promotion, among others. The aim of this multidisciplinary book is to characterize the Escaba reservoir and its drainage basin, considering different geographical and biological aspects to determine the current environmental conditions of the study area. Moreover, it seeks to integrate the acquired knowledge by providing tools that facilitate adequate decision-making on water resources management by government agencies and human communities of the area. This implies proposing concrete actions for a sustainable management of the ecosystem, favoring conservation, protection and/or restoration measures, in this emblematic area of the province of Tucumán. [ABSTRACT FROM AUTHOR]

Introduction: Tropical rivers are increasingly being affected by fragmentation and regulation; and, in Colombia, dams are known to endanger endemic fishes through, among others, limited migration and reduced availability of sediment-based feeding networks. However, knowledge of native ichthyofauna affected by dams in high Andean rivers is still incipient. Objective: To assess the effects of the Neusa dam on the ichthyofauna. Methods: We compared two rivers’ sections, one above and one below the dam with the Richter IHA System, we sampled three 100 m long transects in each section, every two months, between 2017 and 2019. The fishes were returned to the river after body measurements. Results: We collected 729 individuals from five families; Trichomycterus bogotense were smaller under the dam; Oncorhynchus mykiss was smaller and less abundant; and there were no differences for Grundulus bogotensis and Eremophilus mutisii. Independently of climatic factors, O. mykiss and G. bogotensis were more abundant above the dam, and E. mutisii and T. bogotense under the dam. Conclusion: The five fish species differed in how the populations differed above and under the dam, suggesting that some are benefited by the dam, while others become smaller and less abundant. [ABSTRACT FROM AUTHOR]

Copyright of Innotec is the property of Laboratorio Tecnologico del Uruguay and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Agricultura Irrigada - RBAI is the property of Revista Brasileira de Agricultura Irrigada - RBAI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective. To establish the prevalence, diversity and antimicrobial resistance of the zoonotic species of Arcobacter in healthy pigs at slaughterhouse level. Material and methods. Fifty fecal samples were taken by rectal swabs from healthy pigs, before the beginning of the slaughter at the slaughterhouse of Loja city, Southern Ecuador. Sampling was done by means of a non-probabilistic method for convenience. Isolation of Arcobacter strains was done by microbiological methods and species identification using biochemical and molecular (multiplex PCR) tests. Antimicrobial behavior was performed using the disk diffusion method. Results. The four zoonotic species of Arcobacter were found. The isolation rates were A. thereius (18.0%), A. skirrowii (18.0%), A. cryaerophilus (6.0%) and A. butzleri (2.0%). High resistance to ciprofloxacin was found and multi-resistant strains were isolated from these four species. Conclusions. The fecal carriage of the zoonotic species of Arcobacter was demonstrated in pigs at slaughterhouse level. These species showed high resistance to ciprofloxacin being isolated muti-resistant strains among these four species. [ABSTRACT FROM AUTHOR]

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Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the dynamic analysis of the Murallas Viejas reservoir, the response of the rockfill dam of 130 m high was evaluated, during this evaluation, the interaction between the concrete face and the rockfill dam was modeled using advanced techniques. This implementation allowed capturing the concrete face response in term of inertial effects, imposed stresses and its ability for deforming, as well as capturing the slab interaction with each other, the interaction with the rockfill dam and capturing the boundary effects imposed by the plinth. The results of the numerical modelling carried out for the Murallas Viejas reservoir were compared with a similar analysis, but without including the concrete face in the numerical models. For this case the response of the concrete face was indirectly obtained, by a post analysis. The results illustrate the complex interaction between the different dam components and the need of using a correct technique for modelling the dam system. The present work shows the various techniques used and highlight key points of its implementation. The results indicate that the dam response, especially those related to flexural moments at the concrete face, significantly differ between the two cases. The authors believe that this difference is magnified by the inclusion of the transition materials in the numerical analysis. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Sjögren's syndrome is an autoimmune disease that manifests after the age of 45 years and whose incidence increases with age. Symptoms in the oral cavity includes dry mouth or xerostomia. Large number of Sjögren's patients wear complete dentures due to tooth loss at advanced ages. Objective: To describe the case of a Sjögren's patient for whom dentures with salivary reservoirs were made to reduce oral symptoms. Methods: Lab tests were conducted to find an optimum denture design with reservoirs. Requirements included: structural resistance, easy placement and removal of reservoir caps to allow cleaning, good esthetics, and containing the greatest amount of artificial saliva. Models were tried in the patient. Results: Several models were tried for both jaws. At the end, the patient reported about easiness to remove caps, absence of nausea, normal phonetics, adequate hygiene, comfort, and partial solution to the problem of xerostomia with an approximate duration of three hours once the reservoir was full. Conclusion: Final prototypes provided the best characteristics of reservoirs and stored the highest amounts of saliva. It is important to conduct clinical controlled trials to confirm the findings of this case. [ABSTRACT FROM AUTHOR]

Chlamydia psittaci (Cp) is an obligate intracellular bacterium, transmitted through aerosols from nasal and optic secretions, tissues, feces, and feathers. Although commonly identified in birds, genotypes have emerged that can infect new mammalian reservoirs. Therefore, of rectal swabs samples of five Mustella putorios furo individuals and a cloacal swab sample of Colinus cristatus in captivity, in Venezuela, were tested for Cp, using the nested PCR amplifying a segment of the 16S rDNA gene. The presence of Cp was found in four asymptomatic Mustela putorios furo and one symptomatic Colinus cristatus for avian chlamydiosis, indicating a new potential reservoir for Cp. The contact with excretions of infected Colinus cristatus and Psittaciformes, as well as overcrowding, inadequate ventilation, and inadequate sanitary conditions can favor Cp infection. The total number of Cp reservoirs is unknown; therefore, the noting and molecular characterization of isolates enable the understanding, distribution, and diversity of chlamydial agents in wildlife and animals in captivity. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Interuniversitaria de Formación del Profesorado is the property of Asociacion Universitaria de Formacion del Profesorado (AUFOP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work presents the application of HEC-ResPRM and RK3 models to get an optimal operating policy in a multireservoir system belonging to the Sistema Noroeste for water supply of Santiago de Cuba city. The HEC-ResPRM model was applied to get the monthly optimal release for each reservoir to satisfy the target demand of four users. The RK3 model was applied to obtain the so-called dispatch graphs allowing the joint operation of reservoirs to be guided as a function of the actual storage on each one. Other interesting results were to determine the monthly and annual water shortage to the users and a water supply schedule for releases from the reservoirs capable of satisfying 90 % of the annual target demand of all users. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To compare the surgical results of both groups: Simultaneous with the proctocolectomy (SRP) (group 1) or delayed after colectomy (DRP) (group 2). Material and methods: Retrospective study on 126 patients submitted to RP. All patients had a J-pouch, except 4 S. All of them protected with a loop ileostomy. The median time between colectomy and IPAA was 5 months (4-6 range). Clavien-Dindo II-V complications were registered. Results: 126 patients had IPAA. Age median 37 years (12-61 range); 72 (57%) women. SRP in 24 (19%) and DRP was performed in 102 (81%). Postoperative complications were recorded in 19 patients (13%). Wound infection and pelvic sepsis were observed in 4% each. Three patients needed early reoperation: two for hemoperitoneum and one for ischemic necrosis of the pouch. There was no post-operative mortality. No significant difference in 30 days postoperative complication rate was found between SRP and DRP. On long-term follow-up: Intestinal obstruction in 18 patients (14%), pouch-vaginal fistula (PVF) in 9 (12.5%) and chronic pouchitis in 8 (6.9%) were the most common complications. PVF was significantly more frequent on group 1. Conclusion: In this series, no significant difference was found in the early surgical results between group 1 and 2. In the long term, PVF was significantly more common in group 1. [ABSTRACT FROM AUTHOR]

Copyright of Avances is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work present a System for the Operation of Single Reservoir (SOES) accomplished in the mathematical assistant MATLAB using the Storage- Reliability –Yield relationships coupled with Kritski and Menkel methodology for carryover storage reservoir. The SOES implies an optimization mode that uses as objective function the minimization of water shortage cost to users linked to a single reservoir, besides constraints of the reservoir, Kritski and Menkel method and the users demands. The SOES was applied to get the optimal operating policy of Gota Blanca reservoir, including its Hedging Rules, optimal initial storage to get the target demand of three users, monthly shortage of the users and other interesting results for reservoir operation. [ABSTRACT FROM AUTHOR]

Copyright of Geominas is the property of FUNDA-GEOMINAS. (Fundacion de Egresados d Amigos de la Escuela de Ingenieria Geologica y de Minas) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leptospirosis is a disease of great importance in the world because of its zoonotic component, the purpose of this research was to establish a relation between the presence of the disease among domestic, human and wild rodents in Latin America. A review of available bibliography was conducted with an emphasis on reports associated with wild rodents in the last 50 years. As a result it was established that wild rodents that were seropositive to the bacteria, in most cases, had negative culture results and titles were low compared to the seroprevalence in pets, it therefore follows that they are the main risk factor. In conclusion, it is necessary to establish a strict control on livestock farms as well as perform detailed studies, in order to reduce outbreaks in humans and prevent the spread of the disease to wildlife and humans. [ABSTRACT FROM AUTHOR]

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes a linear programming model and Monte Carlo simulation which solve a middle-termed hydrothermal dispatch problem for three different scenarios of wind power penetration. Transmission line effects are neglected. The fuel cost in thermal plants varies in each time period. The test system has two thermal and three hydroelectric plants that can continuously operate during the twelve-months planning term. Wind generation is modeled by using Weibull Distribution Functions particular to the Colombian system, while hydro-generation is modeled by Normal Distribution Functions. Results show costs reduction for the three scenarios of wind power penetration. The main contribution of this paper is to simultaneously introduce the stochastic effect of wind and hydrology in the hydrothermal dispatch. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nutrients enrichment in aquatic ecosystems is given by multiple natural and human factors. Their accumulation in water bodies can lead to undesired consequences on the water quality. Considering that information of nutrients in tropical aquatic ecosystems, specifically in Colombia, is limited, it is important to carry out research projects aiming at conservation and proper management of water resources. In this context, a study of the spatial and temporal changes in nutrient loadings into the Amaní reservoir (Magdalena River mid-basin, Colombia) was carried out considering inter-basins water transfers from Guarinó river to La Miel river. In order to compare the trophic status in the reservoir before and after transfer operations have started, simple eutrophication models were implemented. [ABSTRACT FROM AUTHOR]

La Miel River is a tributary of the Magdalena basin and the main tributary of the Amaní reservoir. In order to establish the spatial and temporal dynamics of periphytic algae genera downstream of the reservoir, data collected every two months between 2006 and 2009, at seven sampling sites (five in the main channel and two tributaries) were analyzed. 130 genera and 15 classes were recorded, Cyanophyceae and Bacillariophyceae being the most representative in density and frequency. Both the generic density and richness showed significant variations in the spatial dimension, but did not differentiate the sampling sites on the La Miel River from those in tributaries and did not show a specific pattern related to hydrological seasons; but changes of richness were observed between samples and a association between the algal community and parameters related to water dynamics was found. We conclude that although the variables analyzed are not limited by the discharge, other structural characteristics of the community such as the taxonomic composition and diversity are affected, especially at the site of direct influence of this process. [ABSTRACT FROM AUTHOR]

We analyzed the diet of Pachyurus bonariensis, captured in the Mocoretá river, Uruguay River, in March 2012. The feeding regime of this perciform agreed with the carnivorous bentophagous type, and the dominant prey of both juveniles and adults, were chironomid larvae and Ephemeroptera nymphs. The adult specimens exhibited a more diverse diet than the juveniles. [ABSTRACT FROM AUTHOR]

This paper describes a linear programming model using AMPL and the solver CPLEX as a mathematical modeling tool in order to solve long term hydrothermal dispatch problem. Transmission line effects are neglected as well as no linearity of fuel cost in thermal plants. Ten hydraulic series with equal probability of occurrence are used, two thermal plants and three basins that begin operating in different time periods of the planning term. Three cases are implemented: Run- of- the-river, restricted reservoir and fully-used-reservoir. [ABSTRACT FROM AUTHOR]

Micropterus salmoides is an important fish species for sport fishing activities, condition that has promoted its introduction to different reservoirs in Mexico and worldwide. With the aim to improve its fisheries management, this research dealt with some reproductive aspects of this species in the Gustavo Díaz Ordaz reservoir, where it was studied from August 2008 through March 2011. To this end, we obtained 938 specimens, with gillnets of different sizes, to determine their total length (Lt, in cm), weight (Pt, in g), sex, gonadosomatic index, condition factor, fecundity and size at first maturity. Lt and Pt ranged from 15.9 to 63cm (37.4±78.0) and 57 to 4 431g (731.7±619.0), respectively. The Pt-Lt relationship showed a positive allometric growth, with no significant difference between males and females (F=0.9955, p=0.3187). The male: female ratio obtained was 1:0.83. Mass spawning lasted from December to April. Size at first maturity was 33.7cm and average fecundity was 32 294±12 878.7 oocytes/female. The gonadosomatic index was low from May through November, and increased between January and March. The condition factor was high before the spawning season and decreased after the reproductive period. We recommend a fishing ban from January to March, and to allow the capture size between 33 and 40cm. [ABSTRACT FROM AUTHOR]

Many activities such as agriculture, animal husbandry and domestic and industrial waste, including effluents of wastewater treatment plants contribute to considerable loads of microbiological contamination, nitrogen, phosphorus, organic matter among others. Riogrande II dam which supplies a conventional treatment plant is not an exception to this problem. In this work the dissolved concentration of organic carbon, total nitrogen, nitrate, nitrite, ammonium and phosphate were evaluated in the influent water of the plant in the period September 2011 to April 2012 and the found concentrations were correlated with the variability of the reservoir level. The results showed nitrate concentrations above those found in previous studies, suggesting a process of nutrients pollution. Correlations with the dam level variation indicate that during the filling period there is an increase of the concentration of nitrogen in the water used for the water purification plant mainly as nitrate and the nature of the organic matter during this period becomes mostly hydrophobic. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ambiente e Água is the property of Revista Ambiente e Agua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eutrophication is caused by contamination of water with nutrients which leads to oxygen depletion thus affecting aquatic life. The present report provides a preliminary analysis of the methodology to obtain a vertical profile of parameters of the eutrophic level in a reservoir, specifically, in Mapara reservoir, source of natural water which is used in the Falcón state. In this area there is agricultural, forestry and tourist activity as well as the contribution of domestic wastewater. The determination of physico-chemical parameters allows inferring the behavior of them, thus obtaining the vertical profile and the level of eutrophication. It is important to consider the measure of the abundance of biomass to obtain a full study. [ABSTRACT FROM AUTHOR]

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Oreochromis aureus is an important fishing resource in this reservoir but little biological information is available for management purposes. To study its age and growth in the site, we obtained samples using gill nets of six mesh sizes, and collecting fish from commercial catches, on a bimonthly basis, from November 2006 to September 2007. Total length (Lt), total weight (Pt), sex and gonadosomatic maturity were analyzed. Age determination was done by readings of scale growth marks, and its validation was made by the marginal and gonadosomatic index. A total of 384 fish were collected. Length and weight varied from 125 to 345mm and from 40 to 671g, respectively. Growth in length and weight are described by the following von Bertalanffy equations: Lt=416 [1-e-0.3682 (t+0.4975)] and Pt=1323[1-e-0.3682(t+0.4975)]]3.0652. Two growth marks per year were registered, these were associated to metabolic and environmental factors like reproduction and temperature. [ABSTRACT FROM AUTHOR]