Belo monte - The proposed Belo Monte dam will be one of the biggest in the world, but deforestation could limit the amount of energy generated Deforestation in the Amazon region could significantly reduce the amount of electricity produced from hydropower, says a new study. Scientists say the rainforest is critical in generating the streams and rivers that ultimately turn turbines. If trees continue to be felled, the energy produced by one of the world's biggest dams could be cut by a third. The study is published in the Proceedings of the National Academy of Sciences. Many countries in tropical regions are turning to hydropower as an untapped source of energy. In Brazil around 45 new hydro plants are in the planning stage. “We now have very strong evidence that Brazil's ability to generate electricity depends on forest conservation” Dr Daniel Nepstad Rainforests, by their very name, are prime locations for the dams that are usually required to create the force of water needed to generate electric power. Until now the presumption has been that cutting down the trees near a dam actually increased the amount of water flowing into the dams. Trees of life But in this new study the researchers took a broader look at the climate projections for the Amazon basin and not just at the rivers on which the dams were built. They found that rainforests are more critical than previously thought as they produce the rain that fills the streams that ultimately drives the rivers and the turbines.

Climate change: Soot's role underestimated

The burning of wood is a major source of black carbon the world over.

Black carbon, or soot, is making a much larger contribution to global warming than previously recognised, according to research.

Scientists say that particles from diesel engines and wood burning could be having twice as much warming effect as assessed in past estimates. They say it ranks second only to carbon dioxide as the most important climate-warming agent. The research is in the Journal of Geophysical Research-Atmospheres. Black carbon aerosols have been known to warm the atmosphere for many years by absorbing sunlight. They also speed the melting of ice and snow. This new study concludes the dark particles are having a warming effect approximately two thirds that of carbon dioxide, and greater than methane.

South Georgia prepares to cull its invasive reindeer

Reindeer have caused great damage to the fragile South Georgian eco-system, trampling native plants and destroying birds' nests and penguin habitats.  

The world's mostly southerly herd of reindeer is to be culled to try to save the environment of the island of South Georgia. The 3,000 reindeer are trampling native plants, causing erosion and endangering king penguins and other local birds by destroying their nests and habitat. A team of Sami herdsmen from Norway have arrived and are preparing to round up and kill the reindeer. The operation is expected to take two southern hemisphere summers.