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Dereglement climatique

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Studying how climate affects biodiversity. A key question in the climate debate is how the occurrence and distribution of species is affected by climate change.

Studying how climate affects biodiversity

But without information about natural variation in species abundance it is hard to answer. In a major study, published in the scientific journal Current Biology, researchers can now for the first time give us a detailed picture of natural variation. Major Advance in Artificial Photosynthesis Poses Win/Win for the Environment. Could smell hold the key to limiting or ending pesticide use? Could smell hold the key to ending pesticide use?

Could smell hold the key to limiting or ending pesticide use?

UK scientists may have uncovered a natural way of avoiding the use of pesticides and help save plants from attack by recreating a natural insect repellent. Scientists from Cardiff University and Rothamsted Research have, for the first time, created tiny molecules which mirror a natural occurring smell known to repel insects. The scientists were able to make similar smelling insect repellent molecules, by providing the enzyme, ((S)-germacrene D synthase), which creates the smell, with alternative substrate molecules. The effectiveness of the smell or perfume to function as an insect repellent was tested. The team found that the smells repelled insects but in one case a reversal of behaviour – an attractant - was observed which raises the prospect of being able to develop a trap-and-kill device.

“However, the difficulty is that scientifically smell molecules are often extremely volatile, chemically unstable and expensive to re-create. How drowsy microbes in Arctic tundra change to methane-makers as permafrost thaws. As the Arctic warms, tons of carbon locked away in Arctic tundra will be transformed into the powerful greenhouse gases carbon dioxide and methane, but scientists know little about how that transition takes place.

How drowsy microbes in Arctic tundra change to methane-makers as permafrost thaws

Now, scientists looking at microbes in different types of Arctic soil have a new picture of life in permafrost that reveals entirely new species and hints that subzero microbes might be active. Such information is key to prepare for the release of gigatons of methane, which could set Earth on a path to irreversible global warming. Appearing in today's issue of Nature, the study will help researchers better understand when and how frozen carbon might get converted into methane. Uncertainties must be taken into account in fisheries stock assessment. Fisheries stock assessment provides information on the status of fish stocks and the impact of fishing on stock development.

Uncertainties must be taken into account in fisheries stock assessment

Since no direct information on fish stock size or fishing mortality rates is available, any conclusions are based on indirect information and the combination of various information sources. By applying new mathematical methods, the uncertainties related to fisheries stock assessment can be taken into account, thus providing more reliable assessments to support decision-making. In her doctoral thesis, Henni Pulkkinen, Researcher at the Natural Resources Institute Finland (Luke), explored how the various sources of uncertainty can be taken into account in fisheries stock assessment by using Bayesian statistical models, which enable extensive combining of information.

For example, biological and ecological data on related species can be utilised in the assessment of many endangered and data poor fish stocks. Nature does not follow a single mathematical formula. Impact of Deepwater Horizon Oil on beach microbial communities. When oil from the Deepwater Horizon spill first began washing ashore on Pensacola Municipal Beach in June 2010, populations of sensitive microorganisms, including those that capture sunlight or fix nitrogen from the air, began to decline.

Impact of Deepwater Horizon Oil on beach microbial communities

At the same time, organisms able to digest light components of the oil began to multiply, starting the process of converting the pollutant to carbon dioxide and biomass. Once the lightest fractions of the oil had been consumed, the organisms that had been digesting those compounds declined, replaced by others able to chew up the remaining heavier materials. Ultimately, a year after the spill, the oil had mostly disappeared and microbial populations buried in the beach sands looked much like they had before the spill, though there were as-yet unexplained differences. More infectious diseases emerging in animals as climate changes, say zoologists. The appearance of infectious diseases in new places and new hosts, such as West Nile virus and Ebola, is a predictable result of climate change, says a noted zoologist affiliated with the Harold W.

More infectious diseases emerging in animals as climate changes, say zoologists

Manter Laboratory of Parasitology at the University of Nebraska-Lincoln. In an article published online today in conjunction with a special issue of the Philosophical Transactions of the Royal Society B, Daniel Brooks warns that humans can expect more such illnesses to emerge in the future, as climate change shifts habitats and brings wildlife, crops, livestock, and humans into contact with pathogens to which they are susceptible but to which they have never been exposed before.

"It's not that there's going to be one 'Andromeda Strain' that will wipe everybody out on the planet," Brooks said, referring to the 1971 science fiction film about a deadly pathogen. "There are going to be a lot of localized outbreaks putting pressure on medical and veterinary health systems. Scientists identify the 13 most important research challenges to face global change in the Mediterranean region.

Scientists consider it key to understand why droughts kill so many trees and the influence of local forest histories on tree mortality.

Scientists identify the 13 most important research challenges to face global change in the Mediterranean region

They also warn that we know very little about the joined effects of different disturbances on each ecosystem, and highlight the necessity to plan research projects covering more time and space. How drowsy microbes in Arctic tundra change to methane-makers as permafrost thaws.