A plateau scale soil moisture and soil temperature observatory is established on the Tibetan Plateau for quantifying uncertainties in coarse resolution satellite and model products of soil moisture and soil temperature. The Tibetan Plateau observatory of plateau scale soil moisture and soil temperature (Tibet-Obs) consists of three regional scale insitu reference networks, including the Naqu ne...

1. In contrast to other social bees, bumble-bees exhibit considerable size variation within the worker caste. This size variation has not been adequately explained, although it is known that larger workers tend to be foragers and smaller bees spend more time in the nest. We quantify size variation and mean size for foragers of 22 bumblebee species inhabiting climates ranging from arctic and mon...

The movement of humans into the Americas remains a major topic of debate among scientific disciplines. Central to this discussion is ascertaining the timing and migratory routes of the earliest colonizers, in addition to understanding their ancestry. Molecular studies have recently argued that the colonizing population was isolated from other Asian populations for an extended period before proc...

Cold air drainage and pooling occur in many mountain valleys, especially at night and during winter. Local climate regimes associated with frequent cold air pooling have substantial impacts on species phenology, distribution and diversity. However, little is known about how the degree and frequency of cold air drainage and pooling will respond to a changing climate. Evidence suggests that, beca...

the upper level pressure patterns control the climate of the surface. the identification of these patterns in the regional scale is useful for the study of the surface climate elements and their forecasting. in order to understand the pressure centers controlling the climate of iran during the cold period of the year, the daily 500 hpa. geopotential height of the grid points of 2.5 degrees dist...

there has been some decline in the land potential capacity in many developing countries, and depending on location,the multi objective management strategy of agroforestry can make effective use of natural resources to be feasible.environmental principles which are effective on agroforestry systems and their components, together with climaticfactors, are the important parameters which been evalu...

introduction climate is a system consisting of atmosphere, lithosphere, cryosphere, hydrosphere, and biosphere. this system is involved in the exchange of energy and moisture among these five components. the exchanges link the atmosphere as the central component of the climate to other spheres. changes do not occur separately in this system; rather change in one component contributes to reactio...