Lecture 9: The Rio de la Plata Basin & the Rio Parana (contd) •Some issues of River Management and Ecology •Dams •Channelization/navigation •Habitat destruction •The Hidrovia •Dams – Itaipu and Yacycreta •The Pantanal and Ibera Wetlands Bonetto et al., 1989 •Length 7235m •Crest elevation 225m; dam is 195m high •Max Q: 62.5 cumecs •10 square kilometers flooded •14,000 MW capacity •First operated 1984 •Reached peak in 2007 •Cost $US 19billion? Itaipu •Length 808m •Raises water 16m above old level •Max Q: 55.5 cumecs •1600 square kilometers flooded •4,050 MW capacity •First operated 19984 •Cost $US 11billion? Jacycreta •Deforestation •Evaporative effects from reservoirs •Sediment yields •Water quality? P levels •Modified hydrographs Bonetto et al., 1989 Estimated suspended sediment transport Funil Porto Primavera - Deriv. Jordao Miranda - Corumbá Salto Caxias Nova Ponte Tres Imaos - Ilha Solterira Yacyretá - Segredo Itaipu - Nova Avanhandava Salto Santiago Capivara Sao Simao - Jose De Moraes 1,0E+07 Mario I. Leao - Salto Osorio Volta Grande 1,5E+07 5,0E+06 Gw calculada (ajuste Pto. Candelaria) Gw calculada (Fuente: Bonetto y Orfeo, 1984) Gw calculada con Cw = 9 mg/l para el período (Fuente: SNRH) Gw calculada con Cw media anual (Fuente: SNRH) 2002 2000 1998 1996 1994 Años 1992 1980 1972 1970 0,0E+00 1968 Gw [ton] Ibitinga 2,0E+07 Chavantes 2,5E+07 Gw calculada por intervalos de Q courtesy Mario Amsler •Eutrophication – algal growth •Segmentation – migratory fishes •Linkages (reduced effects of rapids) •Forest fragmentation •Spread of disease or Bilharzia Drago, 2007 Bonetto et al., 1989 •Seasonal Flooding – up to 5m change •Only part is uninundated •Amazing biodiversity… 650 species of birds, aquatic mammals, monkeys, jaguars, giant anteaters, giant otters Gottgens et al., 2001 Gottgens et al., 2001 •Mining •Illegal hunting/fishing •Agriculture •Deforestation •Hidrovia Hamilton, 1999 Flooded Area, km2 * 103 Hamilton, 1999 Nutrient cycles and major human impacts on the Pantanal Junk and de Cuhna, 2005 Guttgens et al., 2001, Bioscience, 51, 301-308. Junk and de Cunha, 2005, Ecological Engineering, 24, 391-401. see links on course website YOU! •Brainstorming on projects •A review - questions photobucket.com/albums/c75/Buxiu