Cottonwoods (Populus spp.) are adapted to riparian or floodplain zones throughout the Northern Hemisphere; they are also used as parents for fast-growing hybrid poplars. We review recent ecophysiological studies of the native cottonwoods Populus angustifolia James, P. balsamifera L., P. deltoides Marsh., P. fremontii S. Watson and P. trichocarpa T. & G. in North America, and P. nigra L. in Euro...

Repeatability of behavioural and physiological traits is increasingly a focus for animal researchers, for which fish have become important models. Almost all of this work has been done in the context of evolutionary ecology, with few explicit attempts to apply repeatability and context dependency of trait variation toward understanding conservation-related issues. Here, we review work examining...

During an interval of the Late Pliocene, referred to here as the mid-Pliocene Warm Period (mPWP; 3.264 to 3.025 million years ago), global mean temperature was similar to that predicted for the end of this century, and atmospheric carbon dioxide concentrations were higher than preindustrial levels. Sea level was also higher than today, implying a significant reduction in the extent of the ice s...

World agriculture is at a turning point, with high demand due to economic growth accelerating food prices. In addition, energy and climate change are re-defining the equations of supply and demand. Biofuels have a high place on the global agenda, largely due to rising concerns about national energy security, higher energy prices, and increasing concerns about global climate change, as well as t...

There are growing concerns about the health impacts of climate change with ecosystem degradation and global warming, finite reserves of non-renewable energy, water shortages in food-producing regions, limits to contemporary agriculture with its dependence on exhaustible petrochemical nitrogen and rock phosphate fertilizers, and failure of the global financial system. To date, health security ha...

While thewater dependency of water-scarce nations is well understood, this is not the case for countries in temperate and humid climates, even though various studies have shown thatmany of such countries strongly rely on the import of water-intensive commodities from elsewhere. In this studywe introduce amethod to evaluate the sustainability and efficiency of the external water footprint (WF) o...

The dependency of walruses on sea ice as habitat, the extent of their feeding, their benthic bioturbation and consequent nutrient flux suggest that walruses play a major ecological role in Beringia. This suggestion is supported by several lines of evidence, accumulated during more than three decades of enquiry and leading to the hypothesis that positive feedbacks of walrus feeding strongly infl...

Hierarchical distance-based fuzzy multi-criteria group decision making was served as a tool to evaluate the drinking water supply systems of Qom, a semi-arid city located in central part of Iran. A list of aspects consisting of 6 criteria and 35 sub-criteria were evaluated based on a linguistic term set by five decision-makers. Four water supply alternatives including "Public desalinated distri...