8.11D - Recognize human dependence on ocean systems and explain how human activities such as runoff, artificial reefs, or use of resources have modified theses systems.

Human Dependence and Modification 2 Major Systems: Ocean currents Ocean food webs -A few questions to lead them into the next slide: -How do ocean currents affect humans? (historically it determined trade routes; also affects weather) -How do we depend on Ocean food webs? (our food – also other creatures depend on the sea for food/reproduction – think bears eating salmon)

Human Modifications Run Off and Pollution “Red Tides” -Phosphorus/Nitrogen Too much fertilizer used in farming Too much algae growth -Harmful Algal Blooms “Red Tides” Basically when excess nitrogen or phosphorus gets dumped into rivers/streams it is a bad thing. Excess fertilizer in crops/agriculture can lead to this as can factory waste. Eventually all this excess stuff gets dumped into the ocean. Phosphorus and nitrogen happen to be the main food source of many types of algae. HABs (Harmful algal blooms) possibly result from this excess phosphorus/nitrogen being dumped into the ocean. Some HABs occur seasonally and naturally, while others appear to be linked to runoff/pollution. HABs can also be referred to as “Red Tide” for the brown/reddish color that the water takes on when these creatures are rapidly reproducing/feeding on the surface. HABs can kill numerous fish and cause harm to humans who eat said fish.

Human Modifications Over-fishing - Harvesting a fish population to a point of diminishing returns Disrupts the food web May cause organisms to migrate to other areas -Trace the effects of basically eliminating certain parts of the food web. -For example: lets say humans take out most of the tuna in the web – the marlins now have lost one of their main food sources and the squid have lost a main predator. Overfishing of shrimp also takes away a main food source for the tuna, etc. -One thing to consider is that the ocean is constantly in flux. If a species runs out of a food source it may migrate to another area and begin disrupting another marine environment. Some species, however, are limited to a certain range of temperatures water wise, meaning if these creatures lose a food source they may go extinct if they cannot adapt to a different temperature range. -One thing you can extend here are the possible effects of global warming on the food chain. If the water begins to warm overall, creatures must migrate with their temperature range in order to survive. Remember, temperature range that matters in an environment is within 1 or 2 degrees. A 2 degree temperature difference makes a ton of difference in an ecosystem. Imagine water and ice. The difference between 0 degrees Celsius and 2 degrees Celsius is the difference between staying frozen and melting. http://www.youtube.com/watch?v=F6nwZUkBeas

Shark Fins

Human Modifications Artificial Reefs human-made underwater structure, typically built for the purpose of promoting marine life Texas Clipper Artificial reefs are basically a great idea that have a horrible history implementation-wise. For example: in the 1970’s thousands of old car tires were dumped off the coast of Ft. Lauderdale, Florida in order to form an artificial reef. The tires then began to drift away, damaging nearby natural reefs. More recent efforts have had more success, but the main problem is it takes time to form a new reef system. It may be decades before we know if artificial reefs created in the past 10 years are a success. Recent artificial reefs include old warships (stripped of any rubber/plastic or possibly toxic materials) and old subway cars. The video takes about 10 minutes and shows the sinking of the Texas Clipper off Padre Island to form a reef. It also show the marine life that have moved into the ship to create the reef. The ship was sunk on November 17, 2008.

Human Dependence We depend on the ocean for: Oxygen! Phytoplankton contribute 70-80% of the oxygen to Earth’s atmosphere. -Weather: -The oceans absorb lots of energy from the sun. -Warmer water = more evaporation = more rain in a general area; cooler water = less evaporation = less rain in a general area -this also meshes with El Nino/La Nina - both of these climate events occur when trade winds change causing warm/cold water concentrations to change places on the earth which, in turn, affect global weather patterns. -Food: -1/6 of the worlds population relies on the ocean as their primary source of protien. -Transportation: -most of the worlds large bulk goods are transported by ship -Recreation: -Many countries main source of income is through tourism fueled by the ocean. Beach resorts, sport fishing, boating, scuba diving, etc.

Human Dependence We depend on the ocean for: Weather The oceans absorb a lot of energy from the sun. Warmer water = more evaporation = more rain Cooler water = less evaporation = less rain -Weather: -The oceans absorb lots of energy from the sun. -Warmer water = more evaporation = more rain in a general area; cooler water = less evaporation = less rain in a general area -this also meshes with El Nino/La Nina - both of these climate events occur when trade winds change causing warm/cold water concentrations to change places on the earth which, in turn, affect global weather patterns. -Food: -1/6 of the worlds population relies on the ocean as their primary source of protien. -Transportation: -most of the worlds large bulk goods are transported by ship -Recreation: -Many countries main source of income is through tourism fueled by the ocean. Beach resorts, sport fishing, boating, scuba diving, etc.

Human Dependence We depend on the ocean for: Food Transportation Seafood provides a lot of world’s protein. Transportation most of the worlds goods are transported by ship Recreation Many countries main source of income is through ocean tourism -Weather: -The oceans absorb lots of energy from the sun. -Warmer water = more evaporation = more rain in a general area; cooler water = less evaporation = less rain in a general area -this also meshes with El Nino/La Nina - both of these climate events occur when trade winds change causing warm/cold water concentrations to change places on the earth which, in turn, affect global weather patterns. -Food: -1/6 of the worlds population relies on the ocean as their primary source of protien. -Transportation: -most of the worlds large bulk goods are transported by ship -Recreation: -Many countries main source of income is through tourism fueled by the ocean. Beach resorts, sport fishing, boating, scuba diving, etc.

October 2, 2013 What is the result in the relationship between mussels as the zebra mussel invades Texas lakes?

Mangrove Swamps Biodiversity Produce seafood, fruits, medicines, fiber, and wood. Stabilize shores by trapping sediments and building land. Improve water quality by filtering runoff and polluted waters. Protect the climate by absorbing carbon dioxide and reducing the amount of greenhouse gas.

Estuaries – where freshwater streams and rivers flow into ocean Biodiversity Recreational Fishing Shellfish Breeding Grounds Protection from Flood Waters Filter Runoff Environmental, Commercial, and Recreational Benefits

Human Impacts on Ocean Systems Coastal Development Aquaculture (fisheries) Commercial & Recreational Fishing Burning of Fossil Fuels Deforestation Introduction of Invasive Species Agricultural Waste and Pollution Oil Spills Trash Pollution Urban Runoff via Storm Drains Raw Sewage Pollution Industrial Pollution

Consequences Extreme Storms Dead Zones Ocean Acidification Human Displacement Collapsed Fisheries Habitat Destruction Change in Precipitation & Weather Patterns Disrupted Gas Storage and Exchange Human Health Issues Extinction and Loss of Biodiversity Siltation Garbage Patches