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DINÁMICA DEL AGUA EN ANDISOLES BAJO CONDICIONES DE LADERA SOIL WATER DYNAMICS IN ANDISOLS UNDER HILLSLOPE CONDITIONS النص الكامل
2012
Edgar Hincapié Gómez | Conrado Tobón Marín
Resumen. El flujo de agua en el suelo es calificado como un proceso dinámico que regula reacciones químicas y eventos físicos y biológicos, que a su vez influyen en la nutrición, crecimiento y desarrollo de las plantas; es considerado de interés ambiental, ya que influye en la regulación hidrológica, en la distribución y transmisión de agua, solutos y contaminantes a través de la zona no saturada del suelo. El objetivo de este estudio fue evaluar la dinámica de la humedad volumétrica y del potencial matricial del suelo a lo largo de un periodo de secado, en dos Andisoles, localizados en terrenos de ladera en los municipios de Chinchiná (Caldas) y Quimbaya (Quindío) - Colombia. En cada localidad se seleccionaron y aislaron tres monolitos de suelo de 1,5 m de ancho y 6,0 m de largo, con diferente grado de pendiente (20, 40 y 70%, en Chinchiná y 20, 40 y 75%, en Quimbaya). Se instalaron sensores de humedad y tensiómetros a diferentes profundidades y se monitoreó simultáneamente la humedad volumétrica y el potencial mátrico del suelo durante un periodo de 80 días y se obtuvieron las curvas de secamiento del suelo. El modelo potencial se ajustó mejor al comportamiento de la humedad volumétrica con relación al tiempo; en general, la humedad volumétrica se redujo drásticamente durante la primera etapa del drenaje (0-24 horas); posteriormente, le siguió un drenaje lento en el cual los cambios en la humedad volumétrica a través del tiempo fueron mínimos. La tasa de secamiento del suelo aumentó conforme se incrementó el ángulo de inclinación de la pendiente, lo que se atribuye a una refracción del flujo de agua, considerando que el potencial gravitacional está influido por la inclinación de la pendiente y a la vez indica que la pendiente del terreno afecta el movimiento del agua en el suelo.<br>Abstract. Soil water flux is qualified as a dynamic processes that regulate soil chemical reactions, physical and biological events, which in turn influence plant growth and nutrition. Water flow in soils is considered of environmental importance, since it influences the distribution and transmission of water, solutes and contaminants through the vadose zone. The aim of this study was to evaluate the water dynamics and the matric potential of an Andisols, which were determined over a period of wetting and drying of soil monlith, located on a hillslope area close to Chinchiná (Caldas) and Quimbaya (Quindío) - Colombia. At each site, we selected and isolated three soil monoliths of 1.5 m wide and 6.0 m long, with different slope (20, 40 and 70% in Chinchiná and 20, 40 and 75% in Quimbaya). Soil moisture sensors and tensiometers were installed at different soil depths. The soil volumetric moisture and the matric potential were monitored simultaneously, during 80 days, from which we obtained the drying curves. The resulting potential model fitted the best to the soil volumetric moisture behavior in relation to time. In general, volumetric moisture declined faster during the first drying step (0-24 hours), followed by a slow drainage in which the volumetric moisture changes over time were minimum. The rate of soil drying increased as the increased the slope angle, attributed to a refraction of the water flow, whereas the gravitational potential is influenced by the hillslope of the slope and at the time this indicates that this slope controls the soil water movement.
اظهر المزيد [+] اقل [-]DINÁMICA DEL AGUA EN ANDISOLES BAJO CONDICIONES DE LADERA النص الكامل
2012
Hincapié Gómez, Edgar(Centro Nacional de Investigaciones de Café (CENICAFÉ) | Tobón Marín, Conrado(Universidad Nacional de Colombia Facultad de Ciencias Agrarias)
Resumen. El flujo de agua en el suelo es calificado como un proceso dinámico que regula reacciones químicas y eventos físicos y biológicos, que a su vez influyen en la nutrición, crecimiento y desarrollo de las plantas; es considerado de interés ambiental, ya que influye en la regulación hidrológica, en la distribución y transmisión de agua, solutos y contaminantes a través de la zona no saturada del suelo. El objetivo de este estudio fue evaluar la dinámica de la humedad volumétrica y del potencial matricial del suelo a lo largo de un periodo de secado, en dos Andisoles, localizados en terrenos de ladera en los municipios de Chinchiná (Caldas) y Quimbaya (Quindío) - Colombia. En cada localidad se seleccionaron y aislaron tres monolitos de suelo de 1,5 m de ancho y 6,0 m de largo, con diferente grado de pendiente (20, 40 y 70%, en Chinchiná y 20, 40 y 75%, en Quimbaya). Se instalaron sensores de humedad y tensiómetros a diferentes profundidades y se monitoreó simultáneamente la humedad volumétrica y el potencial mátrico del suelo durante un periodo de 80 días y se obtuvieron las curvas de secamiento del suelo. El modelo potencial se ajustó mejor al comportamiento de la humedad volumétrica con relación al tiempo; en general, la humedad volumétrica se redujo drásticamente durante la primera etapa del drenaje (0-24 horas); posteriormente, le siguió un drenaje lento en el cual los cambios en la humedad volumétrica a través del tiempo fueron mínimos. La tasa de secamiento del suelo aumentó conforme se incrementó el ángulo de inclinación de la pendiente, lo que se atribuye a una refracción del flujo de agua, considerando que el potencial gravitacional está influido por la inclinación de la pendiente y a la vez indica que la pendiente del terreno afecta el movimiento del agua en el suelo. | Abstract. Soil water flux is qualified as a dynamic processes that regulate soil chemical reactions, physical and biological events, which in turn influence plant growth and nutrition. Water flow in soils is considered of environmental importance, since it influences the distribution and transmission of water, solutes and contaminants through the vadose zone. The aim of this study was to evaluate the water dynamics and the matric potential of an Andisols, which were determined over a period of wetting and drying of soil monlith, located on a hillslope area close to Chinchiná (Caldas) and Quimbaya (Quindío) - Colombia. At each site, we selected and isolated three soil monoliths of 1.5 m wide and 6.0 m long, with different slope (20, 40 and 70% in Chinchiná and 20, 40 and 75% in Quimbaya). Soil moisture sensors and tensiometers were installed at different soil depths. The soil volumetric moisture and the matric potential were monitored simultaneously, during 80 days, from which we obtained the drying curves. The resulting potential model fitted the best to the soil volumetric moisture behavior in relation to time. In general, volumetric moisture declined faster during the first drying step (0-24 hours), followed by a slow drainage in which the volumetric moisture changes over time were minimum. The rate of soil drying increased as the increased the slope angle, attributed to a refraction of the water flow, whereas the gravitational potential is influenced by the hillslope of the slope and at the time this indicates that this slope controls the soil water movement.
اظهر المزيد [+] اقل [-]Inventario de fuentes de agua subterranea en el Valle Jequetepeque - Chaman
2005
Presenta las caracteristicas generales, caracteristicas geologicas y geomorfologicos,Iventario de fuentes de agua subterranea. Reservorio acuifero. Hidraulica subterranea. Hidrogeoquimica
اظهر المزيد [+] اقل [-]La erosion del suelo por el agua. Algunas medidas para combatirla en las tierras de cultivo
1967
FAO, Rome (Italy). Dirección de Fomento de Tierras y Aguas spa 186726
Efecto de las características ambientales y geológicas sobre la calidad del agua en la cuenca del río Caplina, Tacna, Perú النص الكامل
2017
Pino, Edwin | Tacora, Principe | Steenken, André | Alfaro, Luis | Valle, Angely | Chávarri, Eduardo | Ascencios, David | Mejía, Jesús
Resumen: Se busca determinar la calidad del agua en la cuenca Caplina tomando como componentes principales el análisis de la geomorfología, geología, medio ambiente e hidrología. Para ello, se tomaron los estudios realizados por el Proyecto Especial Tacna (PET), Autoridad Nacional del Agua (ANA), Autoridad Local del Agua (ALA), el Servicio Nacional de Meteorología e Hidrología (SENAMHI), entre otros. Se identificaron tres unidades geomorfológicas, tales como: la Cordillera Occidental, Puna y Flanco Disectado de los Andes con sus características propias; asimismo en base a la cartografía geológica se identificó las formaciones geológicas que inciden sobre la calidad del agua en la Cuenca Caplina. Se determinaron las fuentes con mayor influencia sobre la calidad del agua, siendo las geotermales Aruma y Paralocos que emanan aguas con alto contenido de Arsénico, Plomo y Sodio en concentraciones por encima de los valores del Estándar de Calidad Ambiental (ECA), incluso el trasvase de aguas de la fuente Barroso Chico hacia la Quebrada Ancoma con alto contenido de Hierro. Se identificó las interrelaciones entre la geología, el clima y la hidrología los cuales reflejan la variación de la concentración de los elementos en el agua en épocas de estiaje y épocas de avenida. | Abstract: This work is aimed at determining the water quality in the Caplina basin using a principal components analysis of the geomorphology, geology, environment, and hydrology. To this end, several studies were used, including: Tacna Spatial Project (PET, Spanish acronym) National Water Authority ( ANA, Spanish acronym), Local Water Authority (ALA, Spanish acronym), and the National Weather and Water Service (SENAMHI, Spanish acronym), among others. Three geomorphological units were identified: the Western Cordillera, Puna, and the Andes dissected flank with its own characteristics. In addition, the geological formations that affect the water quality of the Caplina Basin were identified based on the geological cartography. The sources with the greatest influence on water quality were determined. These included the Aruma and Paralocos geothermal springs which produce water with high contents of arsenic, lead, and sodium, in concentrations exceeding the Environmental Quality Standard (ECA, Spanish acronym), and high iron concentration in the water channel from the Barroso Chico spring to the Ancoma Creek. The relationships among the geology, climate, and hydrology were identified, which reflect changes in the concentrations of the elements in the water during seasons with low water levels versus those with high levels.
اظهر المزيد [+] اقل [-]Utilisation des chroniques hydrologiques pour l’identification du fonctionnement et comportement hydrodynamique d’un système karstique en Chine Uso de datos de series hidrológicas temporales para identificar una función hidrodinámica y el comportamiento del sistema de agua kárstica en China 时间序列分析识别岩溶含水系统功能和动态表现 Utilização de séries hidrológicas temporais para identificar o funcionamento e comportamento hidrodinâmicos de um sistema cársico na China | Use of hydrologic time-series data for identification of hydrodynamic function and behavior in a karstic water system in China النص الكامل
2011
Liu, Lihong | Chen, Xunhong | Xu, Guangquan | Shu, Longcang
Karst aquifers are characterized by high heterogeneity and spatial variability of hydrogeological parameters. Time-series analysis of rainfall and discharge (as input and output functions), including correlation, cross-amplitude, phase and coherency, was applied to the Houzhai karstic water system in Guizhou Province, southwest China, in order to study the function, hydrodynamic behavior and hydraulic properties of the aquifer system. Autocorrelation and cross-correlation of the variables showed that the degree of sensitivity of the system to the rainfall input signal decreased gradually from the upstream to the downstream sections, but the memorizing action increased gradually. Analysis of the phase function showed that there is a lag in the discharge response to the rainfall input signal. The lag time increased gradually from the upstream to the downstream sections, and the degree of the linearity upstream is higher than downstream. The quick-flow and slow-flow components were also divided in the cross-amplitude analysis. The results showed that about 60% of spring discharge in the upstream section was quick flow. The quick-flow component downstream reduced to only 5%. The main control factors of the karst-system response are the karst geomorphology and the inner origination structure of the karstic multi-medium.
اظهر المزيد [+] اقل [-]Textos sobre levantamentos de recursos naturais e avaliacao da terra, Primeiro Curso Intensivo de Formacao Profissional, 1983. v. 1: Conceitos e metodologia.- v. 2: Formas do terreno.- v. 3: Avaliacao da terra.- v. 4: O estudo da vegetacao.- v. 5: O estudo dos solos, Anexos. Serie Terra e Agua do Instituto Nacional de Investigacao Agronomica, Documento interno 2.
1984
Spiers B. (ed.)
Spatial analysis of groundwater potential using remote sensing and GIS-based multi-criteria evaluation in Raya Valley, northern Ethiopia | Analyse spatiale du potentiel d’eau souterraine à l’aide d’images satellites et d’évaluation multicritères à partir d’un SIG dans la vallée Raya, Ethiopie du Nord Análisis espacial del potencial del agua subterránea usando sensores remotos y múltiples criterios de evaluación basados en GIS en el Raya Valley, norte de Etiopía 利用基于遥感及GIS的多标准评估方法对埃塞俄比亚北部Raya山谷进行地下水潜力空间分析 Análise espacial do potencial de água subterrânea através do uso de deteção remota e de avaliação multicritério com base em SIG no Vale de Raya, norte da Etiópia النص الكامل
2015
Fenta, Ayele Almaw | Kifle, Addis | Gebreyohannes, Tesfamichael | Hailu, Gebrerufael
Sustainable development and management of groundwater resources require application of scientific principles and modern techniques. An integrated approach is implemented using remote sensing and geographic information system (GIS)-based multi-criteria evaluation to identify promising areas for groundwater exploration in Raya Valley, northern Ethiopia. The thematic layers considered are lithology, lineament density, geomorphology, slope, drainage density, rainfall and land use/cover. The corresponding normalized rates for the classes in a layer and weights for thematic layers are computed using Saaty’s analytical hierarchy process. Based on the computed rates and weights, aggregating the thematic maps is done using a weighted linear combination method to obtain a groundwater potential (GP) map. The GP map is verified by overlay analysis with observed borehole yield data. Map-removal and single-parameter sensitivity analyses are used to examine the effects of removing any of the thematic layers on the GP map and to compute effective weights, respectively. About 770 km²(28 % of the study area) is designated as ‘very good’ GP. ‘Good’, ‘moderate’ and ‘poor’ GP areas cover 630 km²(23 %), 600 km²(22 %) and 690 km²(25 %), respectively; the area with ‘very poor’ GP covers 55 km²(2 %). Verification of the GP map against observed borehole yield data shows 74 % agreement, which is fairly satisfactory. The sensitivity analyses reveal the GP map is most sensitive to lithology with a mean variation index of 6.5 %, and lithology is the most effective thematic layer in GP mapping with mean effective weight of 52 %.
اظهر المزيد [+] اقل [-]Increasing a freshwater lens below a creek ridge using a controlled artificial recharge and drainage system: a case study in the Netherlands | Augmentation de la taille d’une lentille d’eau douce sous une butte de crique à l’aide d’un système contrôlé de recharge artificielle et de drainage: un cas d’étude en Hollande Aumento de lentes de agua dulce por debajo cordones utilizando un sistema controlado de recarga artificial y drenaje: un caso de estudio en los Países Bajos 利用可控的人工补给和排水系统增加小湾地垒之下的淡水透镜体:荷兰的一个研究实例 Ampliação da lente de água doce subjacente a crista de drenagem utilizando um sistema artificial de recarga e dreno: estudo de caso na Holanda النص الكامل
2015
Pauw, Pieter S. | van Baaren, Esther S. | Visser, Martijn | de Louw, Perry G. B. | Essink, Gualbert H. P Oude
A controlled artificial recharge and drainage (CARD) system was used to increase freshwater lenses below creek ridges to increase freshwater supply. Creek ridges are typical geomorphological features that lie up to 2 m higher than the surroundings in the reclaimed tidal flat landscape of the southwestern Netherlands. The 5–30-m thick freshwater lenses below the creek ridges are a vital source for irrigation, as the groundwater and surface waters are predominantly saline. However, freshwater supply from these lenses is commonly not sufficient to meet the irrigation demand, which leads to crop damage. The CARD system was tested in the field and the development of the freshwater lens was monitored during the period May 2013 to May 2014. Numerical models, which were used to investigate a long-term effect of the CARD system, predicted that below the center of the creek ridge, the 13–15-m thick freshwater lens increased 6–8 m within 10 years. The total volumetric increase of the freshwater lens was about 190,000 m³ after 10 years, which was about 40 % of the total recharge (natural and artificial recharge). From this increased freshwater lens, up to three times more water can be extracted using horizontal wells, compared to the initial size of the freshwater lens. A higher water table in the CARD system leads to a thicker freshwater lens but a lower storage efficiency. A lower water table has the opposite effect.
اظهر المزيد [+] اقل [-]Ecology-oriented groundwater resource assessment in the Tuwei River watershed, Shaanxi Province, China | Evaluation axée sur l’écologie de la ressource en eau souterraine dans le bassin versant de la Rivière Tuwei, Province du Shaanxi, Chine Evaluación de los recursos de agua subterránea orientada a la ecología en la cuenca del río Tuwei, provincia de Shaanxi, China 中国陕北秃尾河流域面向生态的地下水资源评价 Avaliação de recursos hídricos subterrâneos orientada a ecologia na bacia do Rio Tuwei, Província de Shaanxi, China النص الكامل
2016
Yang, Z. Y. | Wang, W.K. | Wang, Z. | Jiang, G. H. | Li, W. L.
In arid and semi-arid regions, a close relationship exists between groundwater and supergene eco-environmental issues such as swampiness, soil salinization, desertification, vegetation degradation, reduction of stream base flow, and disappearance of lakes and wetlands. When the maximum allowable withdrawal of groundwater (AWG) is assessed, an ecology-oriented regional groundwater resource assessment (RGRA) method should be used. In this study, a hierarchical assessment index system of the supergene eco-environment was established based on field survey data and analysis of the supergene eco-environment factors influenced by groundwater in the Tuwei River watershed, Shaanxi Province, China. The assessment system comprised 11 indices, including geomorphological type, lithology and structure of the vadose zone, depth of the water table (DWT), total dissolved solids content of groundwater, etc. Weights for all indices were calculated using an analytical hierarchy process. Then, the current eco-environmental conditions were assessed using fuzzy comprehensive evaluation (FCE). Under the imposed constraints, and using both the assessment results on the current eco-environment situation and the ecological constraint of DWT (1.5–5.0 m), the maximum AWG (0.408 × 10⁸ m³/a or 24.29 % of the river base flow) was determined. This was achieved by combining the groundwater resource assessment with the supergene eco-environmental assessment based on FCE. If the maximum AWG is exceeded in a watershed, the eco-environment will gradually deteriorate and produce negative environmental effects. The ecology-oriented maximum AWG can be determined by the ecology-oriented RGRA method, and thus sustainable groundwater use in similar watersheds in other arid and semi-arid regions can be achieved.
اظهر المزيد [+] اقل [-]