Overview of World Rivers and Floridas Rivers Major Rivers River LengthElevation Nile 4145 miles4145 feet Amazon 4000 miles16,962 ft. Yangtze 3964 miles16,542 ft. Longest: Nile Highest Discharge: Amazon Nile = 3721 ft= 0.9 ft/mile 4145 miles Amazon = 16,962 ft = 4.24 ft/mile 4000 miles Yangtze = 16,542 feet = 4.17 ft/mile 3964 miles Gradients The Nile < 1 inch/year The Nile distributaries Alexandria Cairo The Worlds Longest River Length6695 km Discharge 2380 m 3 /s Silts, clays Nutrients The Amazon More flow than the Mississippi, Nile, and Yangtze rivers combined Length4000 miles Elevation 16,962 ft, Width1-6 miles OriginNevado Mismi, Peru (2001) MouthAtlantic Basics Amazon Watershed the size of United States 2,720,000 sq mi 80 110 rainfall/year Discharge: 219,000 m3/s World Hydrology Mouth of Amazon Responsible for a fifth of the total volume of fresh water entering the oceans worldwide 319,000 m per second 20% of freshwater reserves Biodiversity 2.5 million insect species 2000 birds and mammals 75,000 types of trees 150,000 species of plants 1 in 5 $6820/hectare (intact) $1000/hectare (clear cut) $148/hectare (pasture) vanishing at a rate of 20,000 miles per year 10% of the worlds carbon stores in terrestrial ecosystems Deforestation: 300 million metric tons of CO 2 /yr Yangtze third longest river in the world Four hundred million people depend on the Yangtze for freshwater 20% of China's total land area 25% of its total farming land area Almost all of the boating traffic in China TIBETAN PLATEAU flood control hydroelectric power relocation of over 1,500,000 people loss of valuable archaeological and cultural sites The Three Gorges Dam , ,526 Florida Floridas Rivers 1700 rivers and streams Feet to miles wide Recreation Commercial waterways surface water supply St. Johns Kissimmee Suwannee Apalachicola Caloosahachee Floridas Rivers Generally sluggish flow Elevation - Highest point345 ft - Mean98 ft - Lowest point0 ft Florida St. Johns 310 miles 30 feet Kissimmee134 miles 14 feet Suwannee266 miles200 feet Apalachicola112 miles 77 feet Riverlength Elevation Floridas Rivers St. Johns River Laziest river in the world 30 feet over 310 miles ft/mile (1.2 in/mile) Ancient Intracoastal Lagoon System. Barrier islands became an obstacle that prevented water from flowing east to the ocean. Water collected in the flat valley and slowly meandered northward for about 300 miles. St. Johns Atlantic Barrier Island and Reefs St. Johns Forms large lakes and even disappears entirely into the surrounding wetlands bacteria, dioxin, mercury, nutrients, PCBs and sediment nutrients (N and P) are the greatest concern Slow Flow of contaminants Too much nitrogen and phosphorus nutrients spur the growth of too many algae, which itself is a photosynthetic organism. While algae are the vital base of the aquatic food chain, too many algae can crowd together, and the resulting mass (often called blooms) blocks sunlight from reaching underwater plants. Dying algae lower levels of dissolved oxygen in the water, which fish and other aquatic animals breathe. Eutrophication The Kissimmee River 0.1 ft/mile (1.25 in/mile) 14 ft over 134 miles Kissimmee 0.25 ft/mile (3.0 in/mile) chronically low dissolved oxygen levels floodplain utilization by wintering waterfowl declined by 92%. in the 1970s and later, the river contributed about 25% of the nitrogen and 20% of the phosphorus flowing into Lake Okeechobee The Lower Kissimmee River Basin is the second largest source of external phosphorus loading to Lake Okeechobee Kissimmee Okeechobee - Everglades Suwannee River Gradient: 0.75 ft./mile Origin: Okeefenokee Swamp Diverse Largely unspoiled residential and commercial septic systems in rural areas about 300 row crop and vegetable farms, 44 dairies with more than 25,000 animals 150 poultry operations with more than 38 million birds Nitrogen, Phosphorus, bacteria Threats Florida River Types Larger rivers above-average size Flow to Gulf or Atlantic freshwater and marine organisms Slow-moving St. Johns ChoctawhatcheeEscambia Apalachicola Sand-bottom streams Sandy bottoms moderate to swift currents slightly acidic Panhandle Blackwater River Swamp and bog streams originate from swamps, bogs and marshes slow currents dark acidic water suspended organic matter and tannins limited light penetration Hillsborough River Calcareous streams originate from springs colder temperatures clear water rich in calcium and phosphorus alkaline Santa Fe Ichetucknee Weeki Wachee approximately 2,071 miles of Calcareous Streams in Florida North and Central Regions of the State a landscape of distinctive dissolution patterns often marked by underground drainages. areas where the bedrock has a soluble layer or layers, usually, but not always, of carbonate rock such as limestone or dolomite.carbonate Karst Topography