Oasis self-supporting mechanisms due to oasis breeze circulation (OBC) are proposed and simulated numerically in this study using a coupled mesoscale and land-surface model. Excessive evaporation from the oasis makes the oasis surface colder than the surrounding desert surface. The sensible heat-flux gradient from oasis to surrounding desert drives the OBC with downdraft over the oasis and updr...

Numerous studies, including those of desert plants, have shown reduced stomatal conductance under elevated atmospheric CO2. As a consequence, soil water has been postulated to increase. Soil water was measured for .4 yr at the Nevada Desert Free Air CO2 Enrichment (FACE) Facility to determine if elevated atmospheric CO2 conserves soil water for a desert scrub community in the Mojave Desert. We ...

The objectives of this paper were to determine the response of soil quality indicators and organic carbon (OC) distributions within different aggregate classes to changes in land use from desert soils to cropland occurring in the Abarkooh plain, Central Iran. Composite soil samples of the desert soil, wheat and alfalfa fields were taken from three different depths and soil quality indicators, i...

Empirical evidence for large-scale abrupt changes in ecosystems such as lakes and vegetation of semi-arid regions is growing. Such changes, called regime shifts, can lead to degradation of ecological services. We study simple ecological models that show a catastrophic transition as a control parameter is varied and propose a novel early warning signal that exploits two ubiquitous features of ec...

Direct observations of the atmospheric processing of Asian mineral dust R. C. Sullivan, S. A. Guazzotti, D. A. Sodeman, and K. A. Prather Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0314, USA Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, 92093, USA now at: Desert Research Institute, Reno, NV, USA, 895...

Microcolonial structures have been harvested from desert rock samples for cultivation and ultrastructural examination. The results indicate that these microcolonial structures are fungi previously unrecognized as inhabitants of desert rocks.

The previous researches focused on the influence of anthropogenic greenhouse gases exerting global warming, but not consider whether desert sand may warm the planet, this could be improved by accounting for sand's physical and geometric properties. Here we show, sand particles (because of their geometry) at the desert surface form an extended surface of up to 1 + π/4 times the planar area of th...

Populations of Eruca sativa (Brassicaceae) from desert and Mediterranean (Med) habitats in Israel differ in their defense against larvae of the generalist Spodoptera littoralis but not the specialist Pieris brassicae. Larvae of the generalist insect feeding on plants of the Med population gained significantly less weight than those feeding on the desert plants, and exogenous application of meth...

Desert shrubs, a dominant component of desert ecosystems, need to maintain sufficient levels of nutrients in their different organs to ensure operation of various physiological functions for the purpose of survival and reproduction. In the present study, we analyzed 10 elements in leaves, stems, and roots of 24 dominant shrub species from 52 sites across a temperate desert ecosystem in northwes...

We performed a transplant experiment to compare the life histories and morphologies of five geographically representative antlion Myrmeleon hyalinus populations along a sharp climatic gradient, from a Mediterranean climate in Israel's north to a desert climate in the south. Larvae were raised in two environmental chambers simulating Mediterranean and desert climates to investigate the extent to...