Cartografía semi-automática de terrazas de cultivo a partir de datos LiDAR

The mountain systems surrounding the Mediterranean suffered a huge transformation related with the agriculture, mainly as a consequence of the agricultural terraces construction. These structures modify the topography and soils distribution, and, as a consequence, the drainage basins hydro-erosive dynamics. The massive land abandonment especially during the second half of the 20th century conduced to an afforestation associated with the occurrence of wild fires. The combination of fires and the collapse of the terraces walls has accelerated soil erosion processes. Actual sources of topographical data –mainly the airborne LiDAR- and the image analysis tools, offers an adequate resolution to get the land surface elements patters and map landforms such terrace steps. This paper explores the possibilities of such data sources and tools and pretends mapping the terrace walls both active and abandoned for the agricultural practices. Two small catchments have been selected in Mallorca and Castelló as samples characterised by the massive presence of agricultural terraces and using airborne LiDAR data has applied a procedure that produced satisfactory results. The maps have been check by means of photointerpretation and field work, and an exploratory work has been done analysing the influence of the terraces over the erosion processes by means of the study of the structural connectivity applying to the DTMs a Connectivity Index (IC)

Structures spatiales en hydrographie continentale

La compréhension de l'effet des hétérogénéités spatio-temporelles de surface sur la réponse hydrologique et l'adaptation par l'homme de ces hétérogénéités représentent un des enjeux majeurs de l'hydrologie tout en dépassant le cadre de la seule recherche académique. Les recherches en géographie quantitative que j'ai réalisées au cours de ces dix dernières années au sein de l'ENGREF puis d'AgroParisTech s'inscrivent dans cette problématique générale et se sont focalisées sur les hétérogénéités spatiales des supports de transfert des flux hydriques de surface concentrés : les réseaux hydrographiques au sens large (cours-d'eau, plans d'eau, ravines, etc). Les approches développées relèvent de modèles de représentation d'hétérogénéités spatiales sur réseau qui combinent des approches métrologiques (télédétection) et de modélisation spatiale stochastique (géostatistique), pour combler les données manquantes et estimer les incertitudes de représentation. Ainsi, comme je tenterai de l'illustrer, ces modèles de représentation spatiale stochastiques contribuent soit à mesurer l'effet de la précision de la représentation des réseaux sur la réponse hydrologique (finalité méthodologique) soit à explorer numériquement l'effet des hétérogénéités spatiales de réseaux sur la réponse hydrologique ainsi que leurs lois d'échelle (finalités cognitives et prédictives). Parce que les capacités d’adaptation des hétérogénéités spatio-temporelles de ces réseaux dans les paysages cultivés sont un enjeu fort agro-environnemental, j'envisage pour mon projet d'étendre ces modèles à la dynamique des propriétés des réseaux hydrographiques des agrosystèmes

Determinación cartográfica de los muros de piedra seca de la Sierra de Tramuntana mallorquina (Islas Baleares): Análisis exploratorio

The «art of dry-stone walling», declared as Intangible Cultural Heritage by UNESCO, has historically materialized, in Mallorca, with a varied list of constructions with different functions. The massive habilitation of dry stone walls in the Mallorcan rural area has left an outstanding landscape and territorial footprint, which constitutes a rich source of geographical analysis. We present, as an essay, an unpublished cartography of the dry-stone walls located in the Sierra de Tramuntana (Majorca), cartography that has served as the basis for its classification and provisional quantification. With the support of basic techniques of cartography, photointerpretation and GIS, the detailed examination of two official cartographic bases has allowed to determine their usefulness as reliable sources of location and knowledge of dry stone walls in our study area, with a view to a longer range geographical analysis.La técnica constructiva de la piedra seca, declarada Patrimonio cultural inmaterial de la Humanidad por la UNESCO, se ha materializado históricamente, en Mallorca, en forma de un variado elenco de construcciones con diferentes funciones. La masiva habilitación de muros de piedra seca en el espacio rural mallorquín ha dejado una sobresaliente huella paisajística y territorial, que constituye una rica fuente de análisis geográfico. Se presenta, a modo de ensayo, una cartografía inédita de los muros localizados en la Sierra de Tramuntana mallorquina, cartografía que ha servido de base para su clasificación y cuantificación provisional. Con el apoyo de técnicas básicas de cartografía, fotointerpretación y SIG, el examen pormenorizado de dos bases cartográficas oficiales ha permitido dirimir su utilidad como fuentes fidedignas de localización y conocimiento de los muros de piedra seca en nuestro ámbito de estudio, con vistas a un estudio geográfico de los mismos de más largo alcance

Remote Sensing and Geosciences for Archaeology

This book collects more than 20 papers, written by renowned experts and scientists from across the globe, that showcase the state-of-the-art and forefront research in archaeological remote sensing and the use of geoscientific techniques to investigate archaeological records and cultural heritage. Very high resolution satellite images from optical and radar space-borne sensors, airborne multi-spectral images, ground penetrating radar, terrestrial laser scanning, 3D modelling, Geographyc Information Systems (GIS) are among the techniques used in the archaeological studies published in this book. The reader can learn how to use these instruments and sensors, also in combination, to investigate cultural landscapes, discover new sites, reconstruct paleo-landscapes, augment the knowledge of monuments, and assess the condition of heritage at risk. Case studies scattered across Europe, Asia and America are presented: from the World UNESCO World Heritage Site of Lines and Geoglyphs of Nasca and Palpa to heritage under threat in the Middle East and North Africa, from coastal heritage in the intertidal flats of the German North Sea to Early and Neolithic settlements in Thessaly. Beginners will learn robust research methodologies and take inspiration; mature scholars will for sure derive inputs for new research and applications

Remote Sensing of the Aquatic Environments

The book highlights recent research efforts in the monitoring of aquatic districts with remote sensing observations and proximal sensing technology integrated with laboratory measurements. Optical satellite imagery gathered at spatial resolutions down to few meters has been used for quantitative estimations of harmful algal bloom extent and Chl-a mapping, as well as winds and currents from SAR acquisitions. The knowledge and understanding gained from this book can be used for the sustainable management of bodies of water across our planet

Urban Expansion, Land Use Land Cover Change and Human Impacts: A Case Study of Rawalpindi

Urbanization in Pakistan has increased rapidly from 25% in 1972 to 42% in 2012. Peripheral zones are being pushed by urbanization much beyond their previous extents. Moreover, dispersed developments along the highways/motorways and unplanned expansion of existing urban centres is instigating a substantial loss of vegetation and open spaces. This research is an effort to analyse the relationship between urban expansion and land use/cover change using a combination of remote sensing, census and field data. Rawalpindi has been chosen as a study area because of its rapidly changing population density and land cover over the last few decades, and availability of satellite and census data. Landsat MSS and TM images of 1972, 1979, 1998 and 2010 which are compatible with the 1972, 1981, 1998 and 2012 Census of Pakistan dates were classified using the Maximum Likelihood classifier. The results of the assessment of classification accuracy yielded an overall accuracy of 75.16%, 72.5%, for Landsat MSS 1972, 1979 images and 84.5% and 87.1% for Landsat TM 1998 and 2010 images. Results reveal that the built up area of the study area has been increased from 7,017 hectares to 36,220 hectares during the 1972 -2012 period. This expansion has been accompanied by the loss of agricultural and forest land. There has been a decrease of approximately 10,000 hectares in cropped area and 2,000 hectares in forest land of the study area during the 1998-2012 inter-censal period. Corroboration of official census data, remote sensing results and field based qualitative data supports the view that high population growth rate, industrialization, better educational and transportation facilities and proximity of the study area to the capital (Islamabad) are the major factors of urban expansion and resulting land cover changes The present research is expected to have significant implications for other rapidly urbanizing areas of Pakistan in particular, and the Global South in general, in delivering baseline information about long term land use/cover changes

NASA thesaurus. Volume 1: Hierarchical Listing

There are over 17,000 postable terms and nearly 4,000 nonpostable terms approved for use in the NASA scientific and technical information system in the Hierarchical Listing of the NASA Thesaurus. The generic structure is presented for many terms. The broader term and narrower term relationships are shown in an indented fashion that illustrates the generic structure better than the more widely used BT and NT listings. Related terms are generously applied, thus enhancing the usefulness of the Hierarchical Listing. Greater access to the Hierarchical Listing may be achieved with the collateral use of Volume 2 - Access Vocabulary and Volume 3 - Definitions