What are Ecotones? They are transitional areas between two different ecosystems such as forest and grassland or land and ocean. They are not fixed borders, but rather border area’s between two patches of different ecological composition. Ecotones can be created by man-made or natural factors. Man-made factors are for example forest clearing or controlled burning. Natural factors can be soil composition or PH. Ecotones are important indicators of global chance in ecology.
Because they are transitional zones of different ecosystems, there is much biodiversity seen in ecotones. This also makes them more sensitive to changing climate conditions. And thus, they can be used as an indicator in determining the effect of climate change on certain regions of the earth. Monitoring ecotones can show certain patterns in global change. http://www.eoearth.org/view/article/152345/
The effects of climate chance will be seen around the globe, but first in ecotones. This will be clearly seen by their loss in species. And will give early warnings if noticed. Conservation of ecotones is seen as adaptation by the IPCC. Because attention is drawn to prime areas of biomes, ecotones are threatened. It is suggested that 47-77% of ecotones will change because of climate change, which is far more than the 39-55% of prime biomes that are expected to change. An example of threatened ecotones are the semi-arid drylands between arid and dry subhumid drylands. They are threatened directly by desertification and topsoil erosion. These will decline their soil productivity and make them less suitable for plant growth. Climate change will only increase desertification. Since vegetation of these ecotones already experience over exploitation, the climate change happening now will only increase loss of biodiversity, ecosystems and further limit adaptation. If we come to understand this, we also understand that ecotones are unique entities, important to monitor climate change and find ways to adapt to climate change. We have to find ways to conserve these ecotones because then the world will benefit from it and we to as humans (http://www.ipcc.ch/ipccreports/tar/wg2/index.php?idp=669).
Refugia
Refugia are places where natural environmental conditions have remained relatively stable while the earth experienced great environmental change. The high diversity of birds found in the Amazon Rainforest was explained by the idea that when the rainforest experienced climate change, the birds survived in detached pockets of the rainforest. When climate conditions changed, the forest expanded again and so did the bird species. However, some opose this idea stating that the rainforest was not fragmentised during previous periods of climate change. They say the rain forest stayed intact and there are other explanations for its high bird diversity. Still, the term “refugia’ applies to isolated regions where species may survive during times of climate change. An example for such a refugia are the Madean pine oak woodlands in Arizona and northern Mexico. Because these mountains are way above the surrounding deserts, they provide a mocroclimate for plants and animals no longer found in the deserts. They are called Madean sky islands.
Although there remains some controversy about what exactly can be labelled as refugia, the concept of refugia is central to a lot of conservation plans. Areas can be set apart with the purpose of creaing refugia for plants and animals, which is a type of preservation. Conservation International states that we have to search for refugia in order to maintain biodiversityand thus seeking potential refugia can be valuable for conservation. However, predicting which areas can become refugia has to be based on detailed ecological information. This in turn clearly underlines the importance of scientific research (http://www.eoearth.org/view/article/51cbeec57896bb431f69a25c/?topic=51cbfc78f702fc2ba8129e7b).
No comments:
Post a Comment