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This paper provides an in-depth review of evidence for the presence of twelve waterbodies spanning the Late Pliocene through Late Pleistocene in southern Israel and southern Jordan. A comprehensive description of these waterbodies is presented, combined with new field, paleontological and numerical age data, along with a discussion of their implications for paleohydrology and paleoclimate. The region is currently hyper-arid and there are no permanent rivers, wetlands or lakes in the area. Nevertheless, during the time-frame examined, continuous layers of limestones and mudstones were deposited in wetlands and shallow lakes. According to their location, the waterbodies were classified into either resulting from local tectonic depressions or in wide natural depressions at base levels. Following the types of sediments and fauna associated with these waterbodies, it is suggested that four wetter periods occurred: Late Pliocene/Early Pleistocene, Middle Pleistocene, Middle Late Pleistocene and terminal Late Pleistocene. This resulted in the deposition of limestone, chalk, travertine, calcrete, mudstone, marl, clay, silt and sandstone. For several waterbodies, vertical and lateral transitions between white limestone and fine clastic sediments rich in carbonate, indicate changes in depositional conditions from a shallow lake to a wetland, both associated with wetter hydrological settings compared to current climatic conditions. [ABSTRACT FROM AUTHOR]

Biological Soil Crusts (BSCs) are critical components of desert ecosystems worldwide. While all BSCs significantly modify the surfaces they occupy, the manner in which they affect their environment depends on the composition of the microphytic community. The aim of this paper is to study the hyperspectral thermal emissivity signatures of BSCs in order to identify and characterize them in a sand dune environment. The research was conducted in the northwestern Negev dunes. Measurements of several types of BSCs and bare soil were obtained using ground hyperspectral thermal sensors. We present an ability to spectrally separate different types of BSCs from bare sand, and to rank them according to successional development. Based on this ability, we created a spectral index for the discrimination of sand and BSCs of different types and applied it to multispectral remote sensing thermal images. This newly acquired ability to map different BSC types, using remote sensing, may lead to future applications of habitat and ecological function spatial mapping. We also demonstrate how a fusion of reflective and thermal data can be used to map different land-cover features in a sand dune environment. Our proposed thermal index not only discriminates sand and BSCs, but also enhances the signal from limestone pebbles more than other indices, based on reflective data. Unlike remote sensing in the reflective spectral region, thermal remote sensing is unconstrained by solar illumination. High resolution emissivity signatures of land cover are unaffected by environmental variables, as opposed to land-surface temperature that depends on the time of day and the season. [ABSTRACT FROM AUTHOR]

Abstract: At the Ein Gedi oasis, in the Judean Desert, abundant archaeological remains of agricultural irrigation systems are found that were fed only by spring water and used to irrigate the fields that were on the agricultural terraces. The systems date to the Roman-Byzantine period (1st–6th centuries CE) and attest to the existence of a settlement in the oasis at this time. This paper presents a description of the systems and crops grown, based on archaeological surveys and excavations together with a review of historical sources that describe the social mechanisms that enabled the systems to operate. [Copyright &y& Elsevier]

Abstract: Israel is a country with mostly arid environments where is localized extremely large number of archaeological objects of various age, origin and size. The archaeological remains occur in multi-layered and variable geological–archaeological media. In many cases physical properties of the ancient objects are disturbed by long-term influence of arid conditions. These disturbances strongly complicate interpretation of observed geophysical anomalies since the useful signal/noise ratio is often sufficiently reduced. Another disturbing factors are the influence of uneven topography, oblique polarization (especially, for magnetic field analysis) and industrial-engineering objects of different kinds situating in the vicinity of studied remains. From a rich arsenal of the developed techniques (the most part of them is described in ) in the paper are presented the methods of advanced quantitative analysis of potential geophysical fields and 3D magnetic field modelling. A brief archaeological-geophysical review indicates that in Israeli archaeological sites were applied practically all near-surface geophysical methods: beginning from the paleomagnetic examination and ending by microwave remote sensing. Such a diversity of applied methods and constant accomplishing of geophysical, archaeological and other data stipulate creating of a multi-linkage as between the various geophysical methods, so also with other archaeologically related databases. [Copyright &y& Elsevier]

Abstract: This paper reviews and summarizes the results of research projects conducted in the Aleppo pine provenance trial in the Yatir forest, located at the northern edge of the Israeli Negev desert, under semi-arid climate. Results show that to improve the sustainability of new Aleppo pine plantations at the edge of deserts, prospective seed sources (provenances) must be selected for heterozygosity on one hand, and for drought resistance and water-use efficiency on the other. Harsh environmental site conditions at the desert''s edge provide an opportunity to exert heavy selection pressure among and within provenances of a priori drought-tolerant species. The survivors should be used as the seed source for new forest plantations aimed at combating desertification. [Copyright &y& Elsevier]

The Israel–Egypt border region composed of longitudinal sand dunes is a very unique arid environmental ecosystem in the world: the Israeli side with much more vegetation cover has notably higher land surface temperature (LST) during daytime than the Egyptian side where bare sand prevails. In order to understand this thermal anomaly and its scientific significance in the arid environmental ecosystem development, a series of intensive research activities have been conducted in the past several years, including remote sensing analysis and meteorological modeling. In the paper, we present part of the series studies on the issue: the ground temperature measurement and emissivity determination. The region is mainly composed of four basic surface patterns: biogenic crust, bare sand, vegetation and playa (physical crust). Our hypothesis to occurrence of the thermal anomaly is that it is the direct result of the different surface composition structures and ground emissivities on both sides. Results from our ground temperature measurements during 1997–1998 validate the hypothesis of a significant LST difference existing among the main surface patterns of the region. Biogenic crust covering 72% on the Israeli side and only about 12% on the Egyptian side has an average kinetic surface temperature of above 3°C higher than bare sand. Emissivity of the two most important surface patterns also presents a significant difference. Biogenic crust has an average emissivity ranging from 0.9671 at low temperature to 0.9725 at high temperature. Bare sand occupying above 80% of the surface on the Egyptian side and only about 7% on the Israeli side has an average emissivity between 0.9435 and 0.9543. On the basis of the ground temperature measurements, we use the estimated surface cover percentage to factor the emissivity for a simple simulation of average LST on both sides, which results in an outcome that strongly support the explanation of the thermal anomaly in the border region. Since biogenic crust that covers most surface of the region plays important functions in arid ecosystem development and is common in several deserts such as north Africa and central Australia, our documentation of its surface temperature change and determination of its emissivity, which have not been seen in the literature, will provide valuable scientific basis for other studies on arid environmental ecosystems. [Copyright &y& Elsevier]