I. Eglinton of the Eidgenã ssische Technische Hochschule and Raymonde Bonnefille of the Universit d'Aix-Marseille. The role that the environment played in the evolution of hominins--the tribe of human and ape ancestors
In addition the tropical C4-type grasses and shrubs of the modern African savannah began to dominate the landscape earlier than thought replacing C3-type grasses that were suited better to a wetter environment.
While earlier studies on vegetation change through this period relied on the analysis of individual sites throughout the Rift valley--offering narrow snapshots--Feakins took a look at the whole picture by using a sediment core taken in the Gulf of Aden where winds funnel
The combination of marine and terrestrial data enable us to link the environmental record at specific fossil sites to regional ecological
and climate change Levin said. In addition to informing scientists about the environment that our ancestors took shape in Feakins'study provides insights into the landscape that herbivores (horses hippos
and antelopes) grazed as well as how plants across the landscape reacted to periods of global and regional environmental change.
The types of grasses appear to be sensitive to global carbon dioxide levels said Liddy who is currently working to refine the data pertaining to the Pliocene to provide an even clearer picture of a period that experienced similar atmospheric carbon dioxide levels to present day.
Boron is carbon's neighbor on the periodic table with one less electron which might bring in lots of new physics and chemistry especially on the nanoscale.
After the test plots were established the scientists generated two simulated rainfall events. The first occurred
During the first event on plots where residue was removed runoff began around 200 seconds after the rain began.
Runoff from plots protected by residues didn't start until around 240 seconds after it started to rain.
According to the entomologist hoverflies are present in practically all terrestrial ecosystems and they carry out very important biological functions such as pollination nutrient recycling
Most efforts to figure out the ecological workings of the virus have focused on reports of infected people a crude indicator at best says Crowder.
and birds surveys of virus-bearing mosquitoes breeding bird surveys and detailed land use maps and climate data from around the Northwest.
It's still unclear why the habitats would create such a perfect storm for the virus. The researchers speculate that mosquitoes are drawn to orchards for plant nectar during flowering
The technologies many consumers are critical of are those that help us receive the greatest environmental gains Mitloehner said.
Also individual feedstocks within a given region are also quite variable depending on weather conditions handling storage and crop variety.
#How plant communities endure stressthe Stress Gradient Hypothesis holds that as stress increases in an ecosystem mutually supportive interactions become more significant and negative interactions such as competition become less so.
but is backed now by a review of hundreds of studies co-authored in Ecology Letters by Mark Bertness professor of biology at Brown who first formally proposed the hypothesis in 1994.
Ecology is rife with predation competition and other dramatic negative interactions but those alone do not determine the course life On earth.
when ecosystems become threatened by conditions such as drought. Ecologists have argued about the hypothesis ever since Brown University ecologist Mark Bertness co-proposed it in 1994;
Bertness says a large new global meta-analysis he co-authored in Ecology Letters definitively shows that it is true.
The evidence principally analyzed by former Brown visiting graduate student Qiang He of Shanghai Jiao Tong University in China comes from 206 studies of 727 shifts of plant interactions amid varying degrees or gradients
of stress on six continents. Examining the data from each paper and contacting original authors when necessary He determined the overall trends across the many experiments.
In the vast majority of studies as stress increased the significance of interactions shifted toward mutual support in that positive interactions such as those that promoted neighbors'survival strengthened in influence
and negative interactions such as those that hindered neighbors'growth weakened. In some studies stress did not change interactions
Our results show that plant interactions generally change with increased environmental stress and always in the direction of an outright shift to facilitation (typical for survival responses) or a reduction in competition (typical from growth responses) the authors wrote in the paper published online.
These findings were consistent across fitness measures stress types growth forms life histories origins climatic zones ecosystems and methodologies.
The hypothesis and the importance of positive interactions in ecology began to occur to Bertness in the 1970s and 1980s.
Bertness published the Stress Gradient Hypothesis in Trends in Ecological Evolution with Ray Callaway then a graduate student at the University of California-Santa barbara. Callaway is now a professor at the University of Montana.
We're no longer in the casual earlier stages of ecology says biologist Mark Bertness. Nearly two decades later with so much evidence now assembled Bertness said ecologists should feel confident enough in the Stress Gradient Hypothesis to employ it as a rule of thumb.
Rather than continuing to debate whether the hypothesis is said valid he researchers could now focus on crafting experiments to probe how much predictive value the hypothesis has
The hypothesis suggests for example that marine ecosystem managers who want to help tropical fish should focus on sustaining foundational species in the ecosystem such as corals.
With the ecosystem's foundation shored up the natural tendency among species toward greater positive interactions under stress should allow the fish to weather stress better.
We're no longer in the casual earlier stages of ecology Bertness said. In our lifetimes we're watching Caribbean coral reefs die kelp forests die
In other words with nature under stress Bertness hopes that He's efforts to pull together the available data will lead ecologists to pull together
#New research shows complexity of global warmingglobal warming from greenhouse gases affects rainfall patterns in the world differently than that from solar heating according to a study by an international team of scientists in the January 31 issue of Nature.
and Bin Wang (International Pacific Research center University of Hawaii at Manoa) showed that global rainfall has increased less over the present-day warming period than during the Medieval Warm Period
Using an atmosphere-ocean coupled climate model that simulates realistically both past and present-day climate conditions the scientists found that for every degree rise in global temperature the global rainfall rate
since the Industrial revolution has increased less by about 40%than during past warming phases of Earth.
Our climate model simulations show that this difference results from different sea surface temperature patterns.
For the same average global surface temperature increase the weaker SST gradient produces less rainfall especially over tropical land says co-author Bin Wang professor of meteorology.
The increased atmospheric stability weakens the trade winds resulting in stronger warming in the eastern than the western Pacific
and the top of the atmosphere without weakening the trade winds. The result is that heating warms the western Pacific
and smaller increase in yearly rainfall rate will win out concludes Wang. National Basic Research Program and Natural science Foundation of China;
and maples on the University of Michigan's central campus Diag undergraduate researchers and their faculty adviser helped explain an observation that had puzzled insect ecologists who study voracious leaf-munching gypsy moth caterpillars.
Biology and Department of Ecology and Evolutionary Biology. The amount of essential amino acids in oak leaves was 30-42 percent higher than the EAA content of maple leaves in the spring and summer.
In the short term though this is basic research that is driven by the curiosity of ecologists to understand nature better.
I am currently working in a toxicology laboratory at the School of Public health doing research into the human health effects of environmental exposures he said.
The ability to literally walk out the door to work on tree defenses against pests like the gypsy moth coupled with an abundance of undergraduate talent makes the U-M campus an ideal location for studies in insect chemical ecology Barbehenn said.
and environmental NGOS about how individuals can reduce GHG emissions are inappropriate in the European union because of its Emissions Trading System (EU ETS)
and it reduces other forms of environmental pollution but it does not reduce greenhouse gas emissions said Dr Perino an environmental economist in the School of economics and member of the Centre for Social and Economic Research on the Global Environment (CSERGE) at UEA.
He argues that understanding what polices such as the EU ETS cover is crucial for individuals wanting to contribute to reducing their carbon footprint
Consumers who want to reduce the climate impact of their consumption and lifestyle should focus on reducing emissions not regulated by the EU ETS such as road transport agriculture
The EU ETS is the biggest international system for trading GHG emission allowances and a cornerstone of the EU's policy to combat climate change.
The two regional cap and trade schemes in North america the Regional Greenhouse Gas Initiative and the Western Climate Initiative follow the same basic design
Prof Corinne Le Qu r director of UEA's Tyndall Centre for Climate Change Research which works to develop sustainable responses to climate change urged consumers to continue their efforts to reduce their carbon footprint.
It is critical that we significantly reduce our carbon emissions to tackle climate change she said.
which crop water stress is likely are calculated often using atmospheric data such as rainfall and temperatures.
These climate-driven changes could lead to changes in the com po si tion of north east ern forests
and changes over time as the plant adapts to different environmental conditions. The analytical techniques we've demonstrated allow us to measure the range of proteins very deeply
and adapt to environmental surroundings by altering their proteins could help bioenergy researchers develop poplar trees better suited to biofuel production.
This study is encouraging in that it demonstrates that we can monitor a fisher population over a large area with simple methods said Bill Zielinski a PSW research ecologist who coordinated the analysis of the research data.
or wind their decay also releases carbon back into the atmosphere making it critical to quantify tree mortality
in order to understand the role of forests in the global climate system. Tropical old-growth forests may play a large role in this absorption service yet tree mortality patterns for these forests are understood not well.
This new tool will enhance understanding of the role of forests in carbon sequestration and the impact of climate change on such disturbances.
One quarter of CO2 emissions are going to terrestrial ecosystems but the details of those processes and how they will respond to a changing climate are understood inadequately particularly for tropical forests Chambers said.
It's important we get a better understanding of the terrestrial sink because if it weakens more of our emissions will end up in the atmosphere increasing the rate of climate warming.
To develop a better estimate of the contribution of forests we need to have a better understanding of forest tree mortality.
Large-scale tree mortality in tropical ecosystems could thus act as a positive feedback mechanism accelerating the global warming effect.
The Amazon forest is hit periodically by fierce thunderstorms that may bring violent winds with concentrated bursts believed to be as high as 170 miles per hour.
The storms can blow down many acres of the forest; however Chambers and his team were able to paint a much more nuanced picture of how storms affected the forest.
By looking at satellite images before and after a storm the scientists discerned changes in the reflectivity of the forest
which they assumed was due to damage to the canopy and thus tree loss. Researchers were sent then into the field at some of the blowdown areas to count the number of trees felled by the storm.
Looking at the satellite images pixel by pixel (with each pixel representing 900 square meters or about one-tenth of a football field) and matching them with on-the-ground observations they were able to draw a detailed mortality map for the entire landscape
In one particularly violent storm in 2005 a squall line more than 1000 miles long and 150 miles wide crossed the entire Amazon basin.
and stronger storms understanding their effect on tropical and forest ecosystems becomes ever more important. We need to establish a baseline
so we can say how these forests functioned before we changed the climate Chambers said.
This new tool can be used to assess tree mortality in other types of forests as well.
Chambers and colleagues reported in the journal Science in 2007 that Hurricane Katrina killed or severely damaged about 320 million trees.
Disturbances such as Superstorm Sandy and Hurricane Katrina cause large impacts to the terrestrial carbon cycle forest tree mortality and CO2 emissions from decomposition in addition to significant economic impacts.
However these processes are currently not well represented in global climate models. A better understanding of tree mortality provides a path forward towards improving coupled earth system models Chambers said.
Besides understanding how forests affect carbon cycling the new technique could also play a vital role in understanding how climate change will affect forests.
Although the atmospheric CO2 concentration has been rising for decades we are now only just starting to feel the effects of a warming climate such as melting glaciers stronger heat waves and more violent storms.
But these climate change signals will start popping out of the noise faster and faster as the years go on Chambers said.
and on the other hand a warming climate will likely accelerate tree mortality. So which of these processes will win out in the long-term:
and answer this question as climate change processes fully kick in over the coming years. Chambers'co-authors on the PNAS paper were Alan Di Vittorio of Berkeley Lab
#Irrigation in Californias Central Valley intensifies rainfall, storms across the Southwestagricultural irrigation in California's Central Valley doubles the amount of water vapor pumped into the atmosphere ratcheting up rainfall and powerful monsoons across the interior Southwest according to a new study by UC Irvine scientists.
Moisture on the vast farm fields evaporates is blown over the Sierra nevada and dumps 15 percent more than average summer rain in numerous other states.
Runoff to the Colorado river increases by 28 percent and the Four Corners region experiences a 56 percent boost in runoff.
If we stop irrigating in the Valley we'll see a decrease in stream flow in the Colorado river basin said climate hydrologist Jay Famiglietti senior author on the paper which will be published online Jan 29 in the journal Geophysical Research Letters.
and Phoenix. But the extra water vapor also accelerates normal atmospheric circulation he said firing up the annual storm cycle
University painstakingly entered regional irrigation levels into global rainfall and weather models and traced the patterns.
All percent differences in the paper are the differences between applying irrigation to the Central Valley
A better understanding of irrigation's impact on the changing climate and water availability could improve resource management in parched or flooded areas.
#Researchers break million-core supercomputer barrierstanford Engineering's Center for Turbulence Research (CTR) has set a new record in computational science by successfully using a supercomputer with more than one million computing cores to solve a complex fluid
For ground crews even for those wearing the most advanced hearing protection available this creates an acoustically hazardous environment.
and measure processes occurring within the harsh exhaust environment that is otherwise inaccessible to experimental equipment.
These runs represent at least an order-of-magnitude increase in computational power over the largest simulations performed at the Center for Turbulence Research previously said Nichols The implications for predictive science are mind-boggling.
It also reveals clues on how the sequence can be useful to crop improvement for sustainable and resilient food production toward improved livelihoods of smallholder farmers particularly in marginal environments of Asia and Sub-saharan africa.
The research milestone was the result of years of genome analysis by the International Chickpea Genome Sequencing Consortium (ICGSC) led by the International Crops Research Institute for the Semiarid Tropics (ICRISAT) headquartered in Hyderabad Andhra
This will help chickpea farmers become more resilient to emerging challenges brought about by the threat of climate change.
Chickpea is the second largest cultivated grain food legume in the world grown in about 11.5 million hectares mostly by resource poor farmers in the semiarid tropics.
In the face of the growing global hunger and poverty amid the threat of climate change the chickpea genome sequence will facilitate the development of superior varieties that will generate more income
The erosion is a consequence of an unexpected synergy between recreational over-fishing and Great depression-era ditches constructed by Works Progress Administration (WPA) in an effort to control mosquitoes.
The cascade of ecological cause and effect is described by Tyler Coverdale and colleagues at Brown University in a paper published online this month in ESA's journal Frontiers in Ecology and the Environment.
People who live near the marshes complain about the die off because it's not nice to look at said Coverdale.
Without cordgrass protection you also get really significant erosion retreating at sometimes over a meter a year.
but it is also a substantial loss of a valuable ecological resource. When fishermen hook too many predatory fishes out of the marsh's ecosystem the fishes'prey go on fruitfully multiplying unchecked.
The reverberations down the food chain can result in uncomfortable environmental changes for human residents. The problem for Cape cod is the native purple marsh crab (Sesarma reticulatum)
which burrows in the mud along the inner shorelines of the marshes and dines almost exclusively on the tall and fast-growing low marsh cordgrass (Spartina alterniflora) that lines the marsh edges.
The tall and sturdy cordgrass is an essential buffer against the friction of tides and storms.
and bank erosion. The pattern cued the researchers to the possibility that recreational fishing was the trigger Coverdale says.
Marshes are excellent model systems for observing the intersection of human impacts that can trigger environmental degradation the authors say
The Cape cod Mosquito Control Project continues ditch-dredging under the Barnstable County Department of health and the Environment.
when a new awareness of the ecological and economic benefits of the marsh brought strict limitations on further development.
Alone the ditches did not fundamentally alter the marsh ecosystem. The species that colonized the ditches were already present in the marsh;
As a fishing enthusiast himself Coverdale does not see ecologists and fishermen as opposing forces.
The above story is provided based on materials by Ecological Society of America. The original article was written by Liza Lester.
Management and climate change have resulted in younger denser forests that are even more susceptible to attack.
The Dartmouth-led study published in the January issue of the journal Population Ecology confirmed for the first time that the abundance of a certain animal species--in this case the southern pine beetle--fluctuates innately between extremes with no middle ground.
By learning what factors control those tipping points impacts on ecosystems can be averted through monitoring and occasional intervention strategies.
New estimates from a Norwegian project on climate calculationspolicymakers are attempting to contain global warming at less than 2°C. New estimates from a Norwegian project on climate calculations indicate this target may be more attainable than many experts
Climate researcher Caroline Leck of Stockholm University has evaluated the Norwegian project and is enthusiastic. These results are truly sensational says Dr Leck.
If confirmed by other studies this could have far-reaching impacts on efforts to achieve the political targets for climate.
A simple way to measure climate sensitivity is to calculate how much the mean air temperature will rise
Mutual influencesa number of factors affect the formation of climate development. The complexity of the climate system is compounded further by a phenomenon known as feedback mechanisms
i e. how factors such as clouds evaporation snow and ice mutually affect one another. Uncertainties about the overall results of feedback mechanisms make it very difficult to predict just how much of the rise in Earth's mean surface temperature is due to humanmade emissions.
According to the Intergovernmental Panel on Climate Change (IPCC) the climate sensitivity to doubled atmospheric CO2 levels is probably between 2°C
and 4. 5°C with the most probable being 3°C of warming. In the Norwegian project however researchers have arrived at an estimate of 1. 9°C as the most likely level of warming.
Humanmade climate forcingin our project we have worked on finding out the overall effect of all known feedback mechanisms says project manager Terje Berntsen who is a professor at the University of Oslo's Department of Geosciences and a senior
research fellow at the Center for International Climate and Environmental Research--Oslo (CICERO. The project has received funding from the Research Council of Norway's Large-scale Programme on Climate Change and its Impacts in Norway (NORKLIMA.
We used a method that enables us to view the entire earth as one giant'laboratory'where humankind has been conducting a collective experiment through our emissions of greenhouse gases and particulates deforestation and other activities that affect climate.
For their analysis Professor Berntsen and his colleagues entered all the factors contributing to human-induced climate forcings since 1750 into their model.
In addition they entered fluctuations in climate caused by natural factors such as volcanic eruptions and solar activity.
They also entered measurements of temperatures taken in the air on ground and in the oceans. The researchers used a single climate model that repeated calculations millions of times in order to form a basis for statistical analysis.
Highly advanced calculations based on Bayesian statistics were carried out by statisticians at the Norwegian Computing Center. 2000 figures make the differencewhen the researchers at CICERO
and ocean for the period ending in 2000 they found that climate sensitivity to a doubling of atmospheric CO2 concentration will most likely be 3. 7°C
climate sensitivity was reduced greatly to a mere 1. 9°C. Professor Berntsen says this temperature increase will first be upon us only after we reach the doubled level of CO2 concentration (compared to 1750)
Thus when the researchers factor in the observations of temperature trends from 2000 to 2010 they significantly reduce the probability of our experiencing the most dramatic climate change forecast up to now.
This may have caused us to overestimate climate sensitivity. We are most likely witnessing natural fluctuations in the climate system--changes that can occur over several decades--and
which are coming on top of a long-term warming. The natural changes resulted in a rapid global temperature rise in the 1990s
Climate issues must be dealt withterje Berntsen emphasises that his project's findings must not be construed as an excuse for complacency in addressing human-induced global warming.
however that it may be more within our reach to achieve global climate targets than previously thought.
Regardless the fight cannot be won without implementing substantial climate measures within the next few years. Sulphate particulatesthe project's researchers may have shed new light on another factor:
These particulates can act as condensation nuclei for cloud formation cooling the climate indirectly by causing more cloud cover scientists believe.
But the findings of the Norwegian project indicate that particulate emissions probably have less of an impact on climate through indirect cooling effects than previously thought.
and rice in hotter dryer environments with less fertilizer while possibly increasing yields by half the researchers said.
#Parasites of Madagascars lemurs expanding with climate changerising temperatures and shifting rainfall patterns in Madagascar could fuel the spread of lemur parasites
and the diseases they carry. By combining data on six parasite species from ongoing surveys of lemur health with weather data and other environmental information for Madagascar as a whole a team of Duke university researchers has created probability
maps of likely parasite distributions throughout the island today. Then using climate projections for the year 2080 they estimate what parasite distributions might look like in the future.
We can use these models to figure out where the risk of lemur-human disease transmission might be highest
Lemurs are native to the African island of Madagascar where climate change isn't the only threat to their survival.
A key part of saving these animals is ensuring that they stay healthy as environmental conditions in their island home continue to shift Barrett said.
Rainfall drought and cyclone patterns are changing too. In a study published in the January 2013 issue of the journal Biological Conservation Barrett
Warmer weather means that parasites could grow and reproduce more quickly or spread to higher latitudes
and wineswith climate change sparking concern about an increased risk of wildfires scientists are reporting development of a way to detect grapes exposed to smoke from those fires
and intensify with global climate change. Smoke from those fires can travel long distances and poses a special threat for wine grapes.
An important missing piece of the puzzle to understanding how plants cope with stressful environments is knowing
Roots are associated intimately with their environment and develop highly intricate branched networks that enable them to explore the soil.
or salty environments is important in controlling the plant equivalent of fight or flight. To understand how Abscisic acid controls growth the investigators devised a strategy to inhibit the response to this hormone in different tissue layers of the root.
which substances can enter the root system from the soil environment. remarked lead author Duan.
in addition to acting as a filter for substances in the soil the endodermis also acts as a guard with Abscisic acid to prevent a plant from growing in dangerous environments said Dinneny.
And as sea levels rise with climate change understanding how plants particularly crops react to salt might allow us to develop plant varieties that can grow in the saltier soils that will likely occur in coastal zones.
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