Geomorphology and sedimentary/biosedimentary structures of the intertidal environment along the coast of Kuwait,north-western Arabian Gulf

The coast of Kuwait can be divided into nine intertidal geomorphological subunits, of which four are found along the northern muddy shoreline and five along the southern sandy shoreline. In the north the coast is characterized by wide intertidal mudflats, bounded landward by an extensive coastal sabkha which is partly covered by sand drifts. The upper part of the intertidal environment is covered with a mixture of aeolian sands and muddy sediments of marine origin. A number of shallow tidal channels dissect the intertidal flats and small sand bars occur near the low water line. In contrast, the southern shore is characterized by relatively steep sandy beaches fronted by narrow to moderately wide rocky intertidal platforms which are partly covered by sand, bioherms, skeletal debris and algal mats. In some areas the rocky surface is dissected by numerous small gulleys and shallow channels. Multiple sand bars lying either parallel or diagonal to the shoreline are developed near the low water line. This southern intertidal environment is bounded landward by a sandy berm and a wave-cut cliff.Ripple marks are developed almost parallel to the shoreline, showing different flow directions. Energy levels are moderate to high along the southern shore, but low along the northern shore. In the south, waves induced by winds blowing mostly from the north-east and south-east form the dominant energy source, whereas tidal and wind-driven currents are the only tangible process acting along the northern shore.     

A comparison of two models to predict soil moisture from remote sensing data of RADARSAT II

This study investigates the performance of empirical and semiempirical models to predict soil moisture from the data of RADARSAT II synthetic aperture radar (SAR) for the Yarmouk basin in Jordan. Data of SAR were obtained for May and June 2010 and were processed to obtain backscatter (σ ^o ) data for the study area. Results showed significant correlations between soil moisture content (m _v ) and horizontally polarized σ ^o , with coefficient of determination (R ²) of 0.64. The root mean square error for the SAR volumetric soil moisture content was 0.09 and 0.06 m³/m³ for the empirical and semiempirical regression models, respectively. Both models had different clustering patterns in the soil moisture maps in the study area. The spatial agreement between maps of soil moisture was in the range of 55 to 65 % when the maps were reclassified based on intervals of 5 % m _v for both models. In terms of soil moisture interval, both models showed that most of soil moisture changes between the two images (dates) were in the range of ±5 %. Some high differences in ?m _v were observed between the two models. These were mainly attributed to the non-inverted pixels in the soil moisture maps produced by the semiempirical model. Therefore, this model may be applied for a limited range of soil moisture prediction. The use of regression model could predict a wider range for soil moisture when compared with the semiempirical model. However, more work might be needed to improve the empirical model before scaling it up to the whole study area.     

Assessing similarity matching for possible integration of feature classifications of geospatial data from official and informal sources

One difficulty in integrating geospatial data sets from different sources is variation in feature classification and semantic content of the data. One step towards achieving beneficial semantic interoperability is to assess the semantic similarity among objects that are categorised within data sets. This article focuses on measuring semantic and structural similarities between categories of formal data, such as Ordnance Survey (OS) cartographic data, and volunteered geographic information (VGI), such as that sourced from OpenStreetMap (OSM), with the intention of assessing possible integration. The model involves ‘tokenisation’ to search for common roots of words, and the feature classifications have been modelled as an XML schema labelled rooted tree for hierarchical analysis. The semantic similarity was measured using the WordNet::Similarity package, while the structural similarities between sub-trees of the source and target schemas have also been considered. Along with dictionary and structural matching, the data type of the category itself is a comparison variable. The overall similarity is based on a weighted combination of these three measures. The results reveal that the use of a generic similarity matching system leads to poor agreement between the semantics of OS and OSM data sets. It is concluded that a more rigorous peer-to-peer assessment of VGI data, increasing numbers and transparency of contributors, the initiation of more programs of quality testing and the development of more directed ontologies can improve spatial data integration.     

Monitoring land use change in the Badia transition zone in Jordan using aerial photography and satellite imagery

Detection of land use change makes a valuable contribution to the planning and monitoring of drylands. Land use changes at four sites within the Badia transition zone of Jordan were investigated and quantified over the period from 1953 to 1992 using black and white aerial photographs and SPOT PAN satellite imagery digitally merged with Landsat TM. Land use interpretation was checked in the field, and analysed using a Geographical Information System (GIS). Results indicated that land use changes have altered the character of the selected study sites. The important land use changes were from rangeland to rain-fed cultivation, irrigated fields and urban settlements. The increased agricultural activity was reflected in the land use maps through the 39-year period with the appearance of irrigated fields between 1978 and 1992. The land use changes are mainly attributed to the high population growth rate in Jordan and in the Badia, socio-economic change amongst Beduoin and farmers, the land tenure system and to a minor extent environmental factors.