Loss and deterioraton of indigenous habitat increasingly affect natural populations worldwide. As a result of these processes, new selection pressures are imposed upon organisms, increasing local extinction rates. Simultaneously, reduced movement among remnant patches lowers colonisation rates and affects demographic and genetic population parameters. Yet, organisms with comparable life histories often respond to habitat disturbance in various ways. Why so is a matter of great importance to evolution
Study, which shows microscopic plants keep planet warm, offers new considerations for iron fertilization efforts in the oceans
The ecological importance of phytoplankton, microscopic plants that free-float through the world’s oceans, is well known. Among their key roles, the one-celled organisms are the major source of sustenance for animal life in the seas.
Now, in a new study conducted by researchers at Scripps Institution of Oceanography at the University of California,
The movements of two gigantic Antarctic icebergs appear to have dramatically reduced the number of Emperor penguins living and breeding in a colony at Cape Crozier, according to two researchers who visited the site last month. The colony is one of the first ever visited by human beings early in the 20th century.
“It’s certain that the number of breeding birds is way down” from previous years, said Gerald Kooyman, a National Science Foundation-funded researcher at the Scripps Institution
2002 Outbreak May Claim 10,000 Harbor Seals
Scientists from Göteborg University in Sweden and the Woods Hole Oceanographic Institution (WHOI) report in an upcoming issue of the journal Ecology Letters that the 2002 outbreak of phocine distemper virus, or PDV, in European harbor seals may reduce the population by more than half and that future outbreaks with similar characteristics would significantly increase the risk of population declines. Their findings are the first epidemiol
NASA scientists using satellite data have shown that shifts in rainfall patterns from one of the strongest El Niño events of the century in 1997 to a La Niña event in 2000 significantly changed vegetation patterns over Africa.
Assaf Anyamba and Compton Tucker of NASA’s Goddard Space Flight Center, Greenbelt Md., and Robert Mahoney of Global Science and Technology Inc (GST) analyzed satellite derived images of vegetation from 1997 to 2000. They noticed regions of above normal “greenness” ov
An environmentally friendly solution to one of the world’s most notorious chemical contamination problems may be a step closer to reality, reports a research team from Purdue University and the University of British Columbia.
The team has identified one of the key stumbling blocks that prevent microorganisms from decomposing PCBs (polychlorinated biphenyls), a persistent and potentially hazardous industrial chemical that has become nearly ubiquitous in the environment. While capi
Populations of marine fish may lose genetic diversity even if fishing stops while there are still several million individuals – a number previously assumed to be enough to preserve a diverse gene pool.
Losing the diversity of key genes can render a population less productive and unable to adapt when faced with challenges such as global warming, pollution or changes in predators or prey. Rare genetic variation of little importance today might be the key to adaptability in the future, accordin
Generating rainfall for deserts using wind power and seawater is the subject of a new research project.
The idea involves the installation at sea of specially designed wind turbines. The turning motion of the rotors would be harnessed to pump seawater along the turbines’ hollow blades. The water would then be forced out through slits as a fine spray. These drops would evaporate, with salt falling back into the sea and a cloud of water vapour drifting inland, increasing the probabilit
In an effort to stabilize climate and slow down global warming, Livermore scientists along with a team of international researchers have evaluated a series of new primary energy sources that either do not emit or limit the amount of carbon dioxide released to the atmosphere.
Possible candidates for primary energy sources include terrestrial, solar and wind energy; and solar-power satellites; biomass; nuclear fission; nuclear fusion; fission-fusion hybrids and fossil fuels from which carbon h
Models of Larch budmoth outbreaks in the European Alps may eventually show scientists how to model a variety of disease and insect eruptions that rely on a combination of enemy, host and spatial movement to decimate populations, according to a team of ecologists.
“We use theoretical models to help understand the spatial component in these outbreaks and to predict how spatial spread occurs,” says Dr. Ottar N. Bjornstad, assistant professor of entomology and biology at Penn State. “With local
The rapid increase of nitrogen falling from the sky as a result of fossil-fuel combustion and crop fertilization, combined with carbon stored in Earth’s soils, could change the rate of the greenhouse gas, carbon dioxide, rising into the atmosphere, according to a new study.
Scientists believe about 300 times more carbon is stored in soils than is being put in the atmosphere in the form of C02, according to biology Assistant Professor Alan Townsend of the University of Colorado at Bould
The ozone layer is thinning and we do not yet know to what extent future ozone losses will be affected by climate change, or what impact this will have on human health.
For this reason, the European Research Commissioner Philippe Busquin today welcomed the start of the first phase of the VINTERSOL (Validation of International Satellites and Study of Ozone Loss) campaign, composed of national and EU projects. VINTERSOL will be closely co-ordinated with the SAGE III Ozone Loss and Valid
PhD student Rüdiger Lang has developed a method to obtain information about water vapour from satellite data not specifically measuring this. The research is part of a project from the FOM Institute for Atomic and Molecular Physics (AMOLF), the Space Research Organisation Netherlands (SRON) and the Free University of Amsterdam.
Water vapour has a greenhouse effect three times stronger than that of carbon dioxide. Therefore a good picture as to the presence, distribution and influence of wate
A cheap, harmless chemical and sunlight could provide an environmentally friendly way of destroying micro-pollutants in the environment.
UK researchers are developing a new type of reactor to destroy persistent contaminants such as pesticides and pharmaceutical residues.
The technology, which breaks down the polluting molecules into carbon dioxide and water, could provide a breakthrough for a sustainable way of cleaning up fresh water supplies and industrial wastewater.
Th
Laws that favor the use of diesel, rather than gasoline, engines in cars may actually encourage global warming, according to a new study. Although diesel cars obtain 25 to 35 percent better mileage and emit less carbon dioxide than similar gasoline cars, they can emit 25 to 400 times more mass of particulate black carbon and associated organic matter (“soot”) per kilometer [mile]. The warming due to soot may more than offset the cooling due to reduced carbon dioxide emissions over several decades, ac
Two population studies in this week’s issue of THE LANCET highlight how poor air quality is directly related to increased risk of death from respiratory and cardiovascular disease.
Luke Clancy from St James Hospital, Dublin, and colleagues from Trinity College and Dublin Institute of Technology, Dublin, Ireland, and Harvard School of Public Health, Boston, USA, examined the effect of the 1990 coal ban in Dublin on population death-rates in the six years before and after the ban was i
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