9 research outputs found
A Model for Evaluating Soil Vulnerability to Erosion Using Remote Sensing Data and A Fuzzy Logic System
Soil vulnerability is the capacity of one or more of the ecological functions of the soil system to be harmed. It is a complex concept which requires the identification of multiple environmental factors and land management at different temporal and space scales. The employment of geospatial information with good update capabilities could be a satisfactory tool to assess potential soil vulnerability changes in large areas. This chapter presents the application of two land degradation case studies which is simple, synoptic, and suitable for continuous monitoring model based on the fuzzy logic. The model combines topography and vegetation status information to assess soil vulnerability to land degradation. Topographic parameters were obtained from digital elevation models (DEM), and vegetation status information was derived from the computation of the normalized difference vegetation index (NDVI) satellite images. This spectral index provides relevance and is updated for each scene, evidences about the biomass and soil productivity, and vegetation density cover or vegetation stress (e.g., forest fires, droughts). Modeled output maps are suitable for temporal change analysis, which allows the identification of the effect of land management practices, soil and vegetation regeneration, or climate effects
Water Management in Irrigation Systems by Using Satellite Information
Changes in agriculture are associated to the availability of resources and the economic and social demands. One of the more important transformations is to change rainfed into irrigated crops to increase the yield. In most of the cases, water resource and irrigation reservoirs are needed to maintain the yield. However, evaporation from ponds can be an important economic loss and an unsustainable strategy for water management, especially in arid and semiarid regions. Efficient methods for water storage should be established. In this study, a selected area located close to the city of Cartagena (Murcia) and the south of Alicante (Spain) has been studied, where there was an important transformation from rainfed to irrigated crops. Because of the high temperatures and insolation, the increment of the number of reservoirs detected by using remote sensing data and GIS tools may be inefficient for water management. The characterization of these reservoirs, to quantify the potential loss of water due to evaporation, has been done. The use of these tools for analysis could be interesting to find more efficient storage solutions (i.e., better spatial distribution of reservoirs, an increment of depth, and reduction of surface exposure) for improving the water storage and management
Using Landsat Images to Determine Water Storing Capacity in Mediterranean Environments
Reservoirs play an important role in water management and are key elements for water supply. Monitoring is needed in order to guarantee the quantity and quality of stored water. However, this task is sometimes not easy. The objective of this study was to develop a procedure for predicting volume of stored water with remote sensing in water bodies under Mediterranean climate conditions. To achieve this objective,multispectral Landsat 7 and 8 images (NASA) were analyzed for the following five reservoirs: La Serena,La Pedrera, Beniarrés, Cubillas and Negratín (Spain). Reservoirs water surface was computed with the spectral angle mapper (SAM) algorithm.After that, cross-validation regression models were computed in order to assess the capability of water surface estimations to predict stored water in each of the reservoirs. The statistical models were trained with Landsat 7 images and were validated by using Landsat 8 images. Our results suggest a good capability of water volume prediction from free satellite imagery derived from surface water estimations. Combining free remote sensing images and open source GIS algorithms can be a very useful tool for water management and an integrated and efficient way to control water storage,especially in low accessible sites
A Review of Landsat TM/ETM based Vegetation Indices as Applied to Wetland Ecosystems
A review of vegetation indices as applied to Landsat-TM and ETM+ multispectral data is presented. The review focuses on indices that have been developed to produce biophysical information about vegetation biomass/greenness, moisture and pigments.In addition, a set of biomass/greenness and moisture content indices are tested in a Mediterranean semiarid wetland environment to determine their appropriateness and potential for carrying redundant information.The results indicate that most vegetation indices used for biomass/greenness mapping produce similar information and are statistically well correlated.
Piezometric evolution in the aquifer of Aspe (Alicante)
El aprovechamiento de las aguas subterráneas de pequeños acuíferos ha jugado un papel fundamental en el desarrollo local, no siempre bien conocido y valorado. El acuífero de Aspe, en la provincia de Alicante, es un ejemplo en que este aprovechamiento ha estado relacionado históricamente con el crecimiento y desarrollo de la localidad de Aspe. La fuerte presión a la que se vio sometido durante buena parte del s. XX le llevó a una situación de sobreexplotación, de la cual apenas hay información. El abandono de muchas captaciones y la transformación del uso del territorio han permitido un cambio de su situación en las últimas décadas. El principal objetivo del presente trabajo ha sido actualizar el estado de conocimiento que se tiene de él y establecer su situación hidrodinámica. El seguimiento piezométrico ha permitido establecer una sectorización en función del comportamiento de los niveles piezométricos. Así, los sectores de las Fuentes y Tolomó han mostrado un ascenso progresivo, el cual no se corresponde con el comportamiento observado en los sectores de Alcaná y La Ofra. Estas diferencias de comportamiento apuntan a posibles desconexiones piezométricas entre sectores del acuífero.The use of groundwater in small aquifers has played a key role in local development, not always well known and valued. The aquifer of Aspe, in the province of Alicante, is an example in which this exploitation has been historically related to the growth and development of the town of Aspe. The strong pressure to which it was subjected during the twentieth century led to a situation of overexploitation, of which there is scarcely information. The abandonment of many wells and the transformation of land use have allowed a change of its situation in the last decades. The main objective of the present work has been to update the state of knowledge about it and establish its hydrodynamic situation. The piezometric monitoring has allowed to establish a sectorization according to the behaviors of the levels. Thus, the sectors of the Fuentes and Tolomó have shown a progressive piezometric level rise, which does not correspond to the behavior observed in the sectors of Alcaná and La Ofra. These differences in behavior point to possible piezometric disconnections between sectors of the aquifer.Este trabajo se ha realizado dentro del marco del proyecto ALTERACLIM (CGL2015-69773-C2-1) financiado por el Ministerio de Economía, Industria y Competitividad
Soil Sealing and Hydrological Changes during the Development of the University Campus of Elche (Spain)
The University Miguel Hernández of Elche was created in 1996 and its headquarters is located in the city of Elche. A new campus was developed where new buildings and infrastructures have been established for over 25 years in the north of the city. The university is growing, and the land cover/land use is changing, adapted to the new infrastructures. In fact, the landscape changed from a periurban agricultural area mixed with other activities into an urbanized area integrated into the city. The purpose of this work was to evaluate the progressive sealing of the soil and the consequences on the surface hydrology. The area is close to the Palmeral of Elche, a landscape of date palm groves with an ancient irrigation system, which is a World Heritage Cultural Landscape recognized by UNESCO. The evolution of the land occupation was analyzed based on the Aerial National Orthophotography Plan (PNOA). Soil sealing and the modifications of the hydrological ancient irrigation system were detected. Based on the results, proposals for improvement are made in order to implement green infrastructures and landscape recovery that can alleviate the possible negative effects of the soil sealing in the area occupied by the university
Ground to air and back again: archaeological prospection to characterize prehispanic agricultural practices in the high-altitude Atacama (Chile)
In this paper we present an overview of the process of mapping and field surveying of an area of ancient
fields and irrigation canals around the pre-Hispanic sites of Topaín, Paniri and Turi, in the Andean
highlands of northern Chile. As opposed to the usual conditions for prospection in temperate or tropical
regions, where the surface visibility of archaeological features is often poor and confusing, here the
extreme aridity of the landscape has permitted an extraordinary degree of both preservation and visibility
of the fields, canals and other constructions. A field methodology based on a combination of an
aerial approach (with relatively low-cost resources: high resolution satellite images, GIS, UAV) and field
survey has allowed us not only to document the sites but to inject some order into a large assembly of
archaeological features: to understand how the system as a whole was built, and how it evolved and
changed in time, thus allowing for the proposal of a sound hypothetical sequence of the use and
transformation of this area before and after the Inka period
Piezometric evolution in thè aquifer of Aspe (Alicante)
El aprovechamiento de las aguas subterráneas de pequeños acuíferos ha jugado un papel fundamental en el desarrollo local, no siempre bien conocido y valorado. El acuífero de Aspe, en la provincia de Alicante, es un ejemplo en que este aprovechamiento ha estado relacionado históricamente con el crecimiento y desarrollo de la localidad de Aspe. La fuerte presión a la que se vio som etido durante buena p a rte d e ls . X X l e llevó a una situación d e sob reexp lo tación, de la cual apenas hay información. El abandono de muchas captaciones y la transformación del uso del territorio han permitido un cambio de su situación en las últimas décadas. El principal objetivo del presente trabajo ha sido actualizar el estado de conocimiento que se tiene de él y establecer su situación hidrodinámica. El seguimiento piezométrico ha permitido establecer una sectorización en función del comportamiento de los niveles piezométricos. Así, los sectores de las Fuentes y Tolomó han mostrado un ascenso progresivo, el cual no se corresponde con el comportamiento obsen/ado en los sectores de Alcaná y La Ofra. Estas diferencias de comportamiento apuntan a posibles desconexiones piezométricas entre sectores del acuíferoThe use of ground water in small aquifers has played a key role in local development, not always well known and valued. The aquifer ofAspe, in the province of Alicante, is an example in which this exploitation has been historically related to the grow thand development of the town of Aspe .
The strong pressure to which it was subjected during the twentieth century led to a situation of overexploitation, of which there is scarcely information.
The abandonment of many wells and the transformation of land use have allowed achange of its situation in the last decades. The main objective of the present work has been to update the state of knowledge about it and establishits hydrodynamic situation. The piezometric monitoring has allowed to establish a sectorization according to the behaviors of the levels. Thus, the sectors of the Fuentes and Tolomó have shown a progressive piezometric level rise, which does not correspond to the behavior observed in the sectors of Alcaná and La Ofra. These differences in behavior point to possible piezometric disconnections between sectors of the aquife
Piezometric evolution in the aquifer of Aspe (Alicante)
El aprovechamiento de las aguas subterráneas de pequeños acuíferos ha jugado un papel fundamental en el desarrollo local, no siempre bien conocido y valorado. El acuífero de Aspe, en la provincia de Alicante, es un ejemplo en que este aprovechamiento ha estado relacionado históricamente con el crecimiento y desarrollo de la localidad de Aspe. La fuerte presión a la que se vio sometido durante buena parte del s. XX le llevó a una situación de sobreexplotación, de la cual apenas hay información. El abandono de muchas captaciones y la transformación del uso del territorio han permitido un cambio de su situación en las últimas décadas. El principal objetivo del presente trabajo ha sido actualizar el estado de conocimiento que se tiene de él y establecer su situación hidrodinámica. El seguimiento piezométrico ha permitido establecer una sectorización en función del comportamiento de los niveles piezométricos. Así, los sectores de las Fuentes y Tolomó han mostrado un ascenso progresivo, el cual no se corresponde con el comportamiento observado en los sectores de Alcaná y La Ofra. Estas diferencias de comportamiento apuntan a posibles desconexiones piezométricas entre sectores del acuífero.The use of groundwater in small aquifers has played a key role in local development, not always well known and valued. The aquifer of Aspe, in the province of Alicante, is an example in which this exploitation has been historically related to the growth and development of the town of Aspe. The strong pressure to which it was subjected during the twentieth century led to a situation of overexploitation, of which there is scarcely information. The abandonment of many wells and the transformation of land use have allowed a change of its situation in the last decades. The main objective of the present work has been to update the state of knowledge about it and establish its hydrodynamic situation. The piezometric monitoring has allowed to establish a sectorization according to the behaviors of the levels. Thus, the sectors of the Fuentes and Tolomó have shown a progressive piezometric level rise, which does not correspond to the behavior observed in the sectors of Alcaná and La Ofra. These differences in behavior point to possible piezometric disconnections between sectors of the aquifer.Este trabajo se ha realizado dentro del marco del proyecto ALTERACLIM (CGL2015-69773-C2-1) financiado por el Ministerio de Economía, Industria y Competitividad