(Press-News.org) The climate governs the seasonal activity of vegetation; humankind influences it. In the humid mid-latitudes, temperature is the largest influencing factor for plant growth. In predominantly dry areas, however, it is the availability of water and in the high latitudes incident solar radiation. Without a doubt, humankind also has a modifying impact on the ecosystem. Satellites have been recording how the vegetation on the Earth's surface is changing since the 1980s. Within the last thirty years, for instance, vegetation activity has increased in the northern hemisphere but declined in the southern hemisphere. Until recently, it was not possible to quantify the extent to which climate variability, human activity or a combination of the two factors were responsible for this.
An interdisciplinary team headed by geographers Rogier de Jong, Michael Schaepman and mathematician Reinhard Furrer from the University of Zurich, however, has now developed a model together with Dutch colleagues that can illustrate the influences of human activity and climate variability on vegetation separately. To this end, they used satellite data on the vegetation increase or decline from the last thirty years, climate measurements and models, and data on the kind of land cover. The scientists demonstrate that around 54 percent of the changes in global vegetation activity can be attributed to climate variability.
Over 30 percent of the changes caused by human activity
"The majority of the changes – more than 30 percent overall – were caused by human activity," explains de Jong, a postdoctoral student at the University of Zurich's Remote Sensing Laboratories (RSL). Vegetation activity primarily declined south of the Sahel region, such as in Tanzania, Zimbabwe and in the Congo. "We assume that this was caused by clear cutting, the transformation of rainforest into plantations or changes in agriculture in general," explains de Jong. Around ten percent cannot be explained fully by climatology or human activity. "We suspect that this is due to unexplained effects of the interactions between humans and the climate," says Head of the RSL Michael Schaepman.
Schaepman and his team will pursue these interactions further under the newly created research priority program "Global Change and Biodiversity" at the University of Zurich.
INFORMATION:
Literature:
de Jong, R., Schaepman, M.E., Furrer, R., de Bruin, S., & Verburg, P. (2013). Spatial Relationship between Climatologies and Changes in Global Vegetation Activity. Global Change Biology, http://dx.doi.org/10.1111/gcb.12193
de Jong, R., Verbesselt, J., Zeileis, A., & Schaepman, M.E. (2013). Shifts in Global Vegetation Activity Trends. Remote Sensing, (5) (3), 1117-1133, http://dx.doi.org/10.3390/rs5031117
University Research Priority Program "Global Change and Biodiversity"
http://www.uzh.ch/research/priorityprograms/university/2013.html
Contact:
Prof. Dr. Michael Schaepman
Department of Geography
Remote Sensing Laboratories
University of Zurich
Tel. +41 44 635 51 60
E-Mail: michael.schaepman@geo.uzh.ch
A look at the world explains 90 percent of changes in vegetation
2013-04-16
ELSE PRESS RELEASES FROM THIS DATE:
Biodiversity crisis: The impacts of socio-economic pressures on natural floras and faunas
2013-04-16
This press release is available in German.
A new study on extinction risk has shown that proportions of plant and animal species being classified as threatened on national Red Lists are more closely related to socioeconomic pressure levels from the beginning than from the end of the 20th century. Stefan Dullinger of the University of Vienna and Franz Essl from the Austrian Environment Agency together with an international group of researchers reports this new finding in the current issue of PNAS.
It is well understood that the survival of a substantial and increasing ...
Stimulating the brain blunts cigarette craving
2013-04-16
Philadelphia, PA, April 16, 2013 – Cigarette smoking is the leading cause of preventable deaths globally. Unfortunately smoking cessation is difficult, with more than 90% of attempts to quit resulting in relapse.
There are a growing number of available methods that can be tried in the effort to reduce smoking, including medications, behavioral therapies, hypnosis, and even acupuncture. All attempt to alter brain function or behavior in some way.
A new study published in Biological Psychiatry now reports that a single 15-minute session of high frequency transcranial ...
New material gets itself into shape
2013-04-16
Plant components that bend, roll or twist in response to external stimuli such as temperature or moisture are fairly commonplace in nature and often play a role in the dispersal of seeds. Pine cones, for instance, close their scales when wet and open them again once they have dried out. André Studart, a professor of complex materials at ETH Zurich's Department of Materials, and his group have now applied the knowledge of how these movements come about to produce synthetically a composite material with comparable properties.
The secret of the pine cone
Studart and co-workers ...
Forage longer for berries, study on age-related memory decline suggests
2013-04-16
Like birds which stop foraging too early on a berry-laden bush, a new study suggests older people struggle to recall items because they flit too often between 'patches' in their memories.
The study by the University of Warwick published in the journal Developmental Psychology seeks to model the mechanisms behind memory decline in old age.
Its findings indicate that specific changes in the way older people access their memories, rather than a general 'slowing down' in mental processing speed, may be to blame for some aspects of memory decline. Using what is known as an ...
Resurgence of endangered deer in Patagonian 'Eden' highlights conservation success
2013-04-16
The Huemul, a species of deer found only in the Latin American region of Patagonia, is bouncing back from the brink of possible extinction as a result of collaboration between conservationists and the Chilean government, says a new study.
By controlling cattle farming and policing to prevent poaching in the Bernardo O'Higgins National Park – a vast "natural Eden" covering 3.5 million hectares – conservation efforts have allowed the deer to return to areas of natural habitat from which it had completely disappeared.
Researchers are hailing the findings as an example of ...
Researchers devise X-ray approach to track surgical devices, minimize radiation exposure
2013-04-16
Researchers from North Carolina State University and the University of North Carolina at Chapel Hill (UNC) have developed a new tool to help surgeons use X-rays to track devices used in "minimally invasive" surgical procedures while also limiting the patient's exposure to radiation from the X-rays.
Many surgical procedures now use long, thin devices – such as "steerable needles" – that can be inserted into a patient's body through a small incision and then steered to a target location. These "minimally invasive" procedures allow doctors to perform surgeries without having ...
Liverpool Bay sediment discovery could save millions
2013-04-16
New research tracking the movement of dredged sediment around Liverpool Bay could save millions of pounds, according to scientists at the National Oceanography Centre in Liverpool.
Each year, sediment has to be dredged from the port and deposited elsewhere to maintain access for commercial vessels. But according to the new study, the dredged material appears back in the port again within just a few weeks of its removal, carried by sea currents.
"There are two competing sediments coming in; from the sea and from the river," says Dr Alex Souza of the Natural Environment ...
For the very first time, 2 spacecraft will fly in formation with millimeter precision
2013-04-16
Spanish industry is leading the Proba-3 mission, a world first in precise formation flying. This European Space Agency (ESA) project aims to demonstrate that two satellites can move as one single object with sub-millimetre precision. This configuration will enable the creation of enormous space telescopes with the lens and detector hundreds of metres apart.
"Proba-3 will be the first mission in which two spacecraft will fly through space as a single unit, pointing at selectable directions, and with sub-millimetre precision, in other words, relative position accuracy to ...
Catch me if you can: 2 new species of moth from the Russian Far East
2013-04-16
Ypsolophid moths are a peculiar group of Lepidoptera that attracts attention with their strange preference for a pose of rest. To take a break adult Ypsolophids like to go bottom up with antennae stretched forward. The larvae of these quirky species live and feed in webs they form on the leaves, buds and twigs of plants. When they are ready to pupate they produce a cocoon like cradle attached to the host plant.
This bizarre group of moths is also particularly hard to catch. The standard methods for collecting adults, usually comprising of breeding them from larvae or ...
Fun activities can improve language learning, Nottingham academics reveal
2013-04-16
Playing simple games using words and pictures can help people to learn a new language with greater ease, researchers from The University of Nottingham have shown.
Their study, published by the scientific journal PLOS ONE, revealed that using fun, informal ways of learning not only helped complete novices to acquire a new language but also made more traditional methods of language learning more effective.
PhD student Marie-Josée Bisson of the University's School of Psychology, who led the study along with Drs Walter van Heuven, Kathy Conklin and Richard Tunney, said: ...