The Paraguay-Parana River system is the second largest river system in South America — second only to the Amazon. More than 100 million people and some of the rarest species on Earth depend on healthy waters of the Paraguay-Parana River system for survival.

The middle Parana River forms the country boundaries of Paraguay and Argentina in South America. A joint project between the countries began in December of 1983 with construction of the Yacyreta Dam. Also named Hydroelectric Power Station Jasyreta-Apipe, the power plant began operating in 1994.

The May 1985 Landsat image shows the area shortly after dam construction began, while the river was close to its traditional boundaries. The resulting lake formed by the project, as seen in the December 1999 and June 2010 images, has been the source of many problems for people living along the river. River levels rose dramatically upon completion of the dam, initially displacing 15,000 residents and endangering the homes of 800,000 more. Additionally, the source of the Parana River - the Atlantic Forest - harbors a range of biodiversity comparable to that found in the Amazon, including 1,000 species of birds and species such as the brown howler monkey that are found nowhere else on Earth.

The Paraguay River floods the spectacular Pantanal - the world's largest freshwater wetland - a habitat for jaguars, giant river otters, and 650 species of birds like cormorants, herons, and jabiru storks.

The Paraguay River cuts through the Brazilian Cerrado, a grassland home to more than 10,000 species of plants as well as maned wolves and giant anteaters.

Landsat satellite data are being used for monitoring the effects of the dam construction upstream and are being used by national and international governing bodies and conservation groups in attempts to minimize the damage done by altering the stream flow.

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Wednesday, February 2, 2011