Der Schutz des Regenwaldes Amazoniens bedeutet nicht nur den Erhalt der Artenvielfalt in Flora und Faune. Ein intakter Regenwald hat auch klimatische Auswirkungen, er bringt viele Niederschläge und füllt die Flüsse. Das ist für die Energieerzeugung durch Waserkraftwerke sehr wichtig. Je mehr Wald also vorhanden ist, desto größer ist die Kapazität eines Wasserkraftwerkes.
Eine fortschreitende Abholzung des Regenwaldes hingegen führt zu einer Verringerung der Niederschläge und zu einem sinkenden Wasserpegel der Flüsse. Die Stromerzeugung durch Wasserkraft in Belo Monte könnte sich bis zu 40 % reduzieren, wenn die momentane Rodungsintensität anhält.
Dies ist das Ergebnis einer Studie, die von brasilianischen Wissenschaftlern am Montag (13.5.) in der amerikanischen Zeitschrift PNAS veröffentlicht wurde.
Blickpunkt Lateinamerika, 5.6.2013
Holzeinschlag drosselt Wasserkraft von Belo Monte
Mit zunehmendem Holzeinschlag im brasilianischen Amazonas-Regenwald könnte das im Bau befindliche Wasserkraftwerk ´Belo Monte´ bis zu einem Drittel seines Energiepotenzials einbüßen. Zu diesem Ergebnis kommt eine Untersuchung des Umweltforschungsinstituts IPAM.
Veja, 14.5.2013
Pesquisa afirma que desmatamento da Amazônia pode diminuir geração de energia de Belo Monte
Cientistas brasileiros mostram que a perda de floresta pode afetar a quantidade de chuvas na região, levando a um fluxo menor de água nos rios e a um corte de até 40% na geração de energia prevista na hidrelétrica
Estadão, 14.5.2013
Quanto mais floresta, maior será a capacidade de Belo Monte, diz estudo
Caso a perda da vegetação atinja 40% do bioma, em 2050, a produção de energia pode cair a 25% da capacidade
Dependence of hydropower energy generation on forests in the Amazon Basin at local and regional scales
Tropical rainforest regions have large hydropower generation potential that figures prominently in many nations’ energy growth strategies. Feasibility studies of hydropower plants typically ignore the effect of future deforestation or assume that deforestation will have a positive effect on river discharge and energy generation resulting from declines in evapotranspiration (ET) associated with forest conversion. Forest loss can also reduce river discharge, however, by inhibiting rainfall. We used land use, hydrological, and climate models to examine the local “direct” effects (through changes in ET within the watershed) and the potential regional “indirect” effects (through changes in rainfall) of deforestation on river discharge and energy generation potential for the Belo Monte energy complex, one of the world’s largest hydropower plants that is currently under construction on the Xingu River in the eastern Amazon. In the absence of indirect effects of deforestation, simulated deforestation of 20% and 40% within the Xingu River basin increased discharge by 4–8% and 10–12%, with similar increases in energy generation. When indirect effects were considered, deforestation of the Amazon region inhibited rainfall within the Xingu Basin, counterbalancing declines in ET and decreasing discharge by 6–36%. Under business-as-usual projections of forest loss for 2050 (40%), simulated power generation declined to only 25% of maximum plant output and 60% of the industry’s own projections. Like other energy sources, hydropower plants present large social and environmental costs. Their reliability as energy sources, however, must take into account their dependence on forests.
