the kopet-dagh basin extended in the north and north east of iran and consists of marine strata from middle jurassic to paleogene time. abtalkh formation is one of the thickest lithostratigraphic units of cretaceous in the kopet-dagh basin and is composed of light gray, green to bluish marl and silty marl. the abtalkh formation conformably overlies the marls and chalky limestones of the abderaz...

Forests historically associated with frequent fire have changed dramatically due to fire suppression and past harvesting over the last century. The buildup of ladder fuels, which carry fire from the surface of the forest floor to tree crowns, is one of the critical changes, and it has contributed to uncharacteristically large and severe fires. The abundance of ladder fuels makes it difficult to...

Land cover (LC) products, derived primarily from satellite spectral imagery, are essential inputs for environmental studies because LC is a critical driver of processes involved in hydrology, ecology, and climatology, among others. However, existing LC products each have different temporal and spatial resolutions and different LC classes that rarely provide the detail required by these studies....

We compared forest floor depth, soil organic matter, soil moisture, anaerobic mineralizable nitrogen (a measure of microbial biomass), denitrification potential, and soil/litter arthropod communities among old growth, unthinned mature stands, and thinned mature stands at nine sites (each with all three stand types) distributed among three regions of Oregon. Mineral soil measurements were restri...

The United Nations has declared the year 2002 as the «International Year of Mountains». This fact alone underlines the importance of mountain regions in various respects: ◆ Mountains make up 24% of the Earth’s total landmass ◆ All major rivers and 60–80% of the Earth’s freshwater resources originate in mountain regions ◆ Mountain forests account for 28% of the Earth’s total forested area ◆ Moun...

Two state-of-the-art Earth systemmodels (ESMs) were used in an idealized experiment to explore the role of mountains in shaping Earth’s climate system. Similar to previous studies, removing mountains from both ESMs results in the winds becoming more zonal and weaker Indian and Asian monsoon circulations. However, there are also broad changes to the Walker circulation and El Niño–Southern Oscill...

The scattered eastern African high mountains harbor a renowned and highly endemic flora, but the taxonomy and phylogeographic history of many plant groups are still insufficiently known. The high-alpine populations of the Geranium arabicum/kilimandscharicum complex present intricate morphological variation and have recently been suggested to comprise two new endemic taxa. Here we aim to contrib...

The authors begin the paper with the question `Do mountains exist?' They show that providing an answer to this question is surprisingly difficult and that the answer that one gives depends on the context in which the question is posed. Mountains clearly exist as real correlates of everyday human thought and action, and they form the archetype for geographic objects. Yet individual mountains lac...