Unit 2_ Comparing Aquatic Ecosystems Slides.pdf

Unit 2: Comparing Aquatic Ecosystems Texas Aquatic Science: 2EFHJ, 3ABDEF, 9ABC, & 10C 9A: Fresh, Brackish, & Marine Ecosystems Freshwater Ecosystems: ○ Freshwater ecosystems are any aquatic ecosystems with a salt concentration measurement of less than 0.5 ppt. ○...

Unit 2: Comparing Aquatic Ecosystems Texas Aquatic Science: 2EFHJ, 3ABDEF, 9ABC, & 10C 9A: Fresh, Brackish, & Marine Ecosystems Freshwater Ecosystems: ○ Freshwater ecosystems are any aquatic ecosystems with a salt concentration measurement of less than 0.5 ppt. ○ Examples: Rivers, Lakes, Streams, Ponds, Aquifers, Springs Brackish Ecosystems: ○ Ecosystems where fresh and saltwater mix; salt concentration measurement between 0.5 and 30 ppt. ○ Examples: estuaries, mangrove swamps, marshes, some areas of seas, and some lakes Marine Ecosystems: ○ Saltwater ecosystems with salt concentrations above 30.0 ppt. ○ Examples: oceans & seas All photos from Google Images 9B: Properties & Components of Different Life Zones Freshwater Life Zones: LAKES (Lentic): Littoral Zone - upper zone, near the shore, that receives sunlight; absorbs nutrients from runoff; high levels of plant and animal life Limnetic Zone - upper zone, away from the shore, that receives sunlight; depth reaches until little sunlight penetrates; life includes plankton, crustaceans, and some fish. Profundal Zone - deep, open water where no sunlight penetrates; water is colder and more dense; lack of light results in very little photosynthesis, resulting in low levels of oxygen; little to no plant life and benthic microorganisms populate the profundal zone Benthic Zone - very bottom of the freshwater lake where zero sunlight is available; benthic detritivores live in this zone, breaking down scraps and dead organic matter that falls to the bottom. Oligotrophic lakes - low nutrient levels, resulting in low biodiversity; clear waters due to lack of plant growth; colder climates; ex: Lake Joseph in New York Mesotrophic lakes - moderate levels of nutrients; relatively clear waters; high levels of biological productivity; ex: Lake Travis in Austin, TX Eutrophic lakes - large nutrient supplies, humans contributions can lead to cultural eutrophication; due to eutrophication, high levels of oxygen are lost; ex: Lake LBJ near Austin (used to be Mesotrophic, but pollution led to eutrophication of this lake) http://www.actforlibraries.org/zones-found-in-freshwater-lakes/ 9B: Properties & Components of Different Life Zones Freshwater Life Zones: RIVERS (Lotic): Source Zone - upper most part of the river; fast moving waters producing high levels of dissolved oxygen; light available but not productive due to moving water; some plant-life present Transition Zone - wider bodies with slower-moving and warmer waters; lower dissolved oxygen; higher biodiversity supported Floodplain Zone - wider & deeper portion of the river; even slower water & less dissolved oxygen; high levels of nutrients; help filter out pollutants before entering oceans & seas; high levels of biodiversity https://www.ohio.k12.ky.us/userfiles/1421/Classes/16600/Chapter%208%20Notes.pdf 9B: Properties & Components of Different Life Zones Marine Life Zones (Vertical): Epipelagic (Sunlight) Zone - surface waters; sunlight availability (photic) which provides high levels of biological productivity; organisms include: plankton, sharks, rays, large game fish, jellyfish, sea turtles, etc Mesopelagic (Twilight) Zone - not enough sunlight available (photic) for photosynthesis; water pressure increases & temps decrease; organisms include: octopus & squid Bathypelagic (Midnight) Zone - no light available (aphotic); bioluminescent (cells that produce light) organisms become more present; organisms include: chemosynthetic algae; angler fish; & sperm whales that dive down for food Abyssopelagic (Abyssal) Zone - no light (aphotic); intense pressure; mostly invertebrates live here (due to pressure), including: squid and sea stars Hadalpelagic (Hadal) Zone - the trenches; extreme pressure and freezing temperatures; Mariana Trench is the deepest part of the ocean; very little life here: grenadiers, cusk eels, & pearlfish https://www.capeclasp.com/blogs/cape-clasp-blog/the-5-ocean-zones-and-the-creatures-that-live-within-them 9B: Properties & Components of Different Life Zones Marine Life Zones (Horizontal): Intertidal (Littoral) Zone - shoreline area between high and low tides; organisms include: sea stars, snails, seaweed, algae, crabs; some organisms are adapted to grip or stay attached to rocks due to constant water movement Neritic (Sublittoral) Zone - shallow area extending from shoreline; corresponds with continental shelf; most biological productive horizontal life zone & includes coral reef ecosystems; organisms include: coral, crustaceans, mollusks, sponges, kelp, sea anemone, seagrass, sharks, tropical fish, etc Oceanic Zone - open ocean, beyond the continental shelf;include photic and aphotic zones (vertical); not as productive as Neritic, but include a wide array of life including: plankton, large game fish, whales, sharks, eels, bioluminescent fish,etc. All photos from Google Images 9B: Properties & Components of Different Life Zones Components of Life Zones: Salinity - amount of dissolved salt in each zone Seasonal Trends in Water Temperature - effects of seasonal changes to the temperature of water Dissolved Oxygen - availability of DO in each zone; more plant-life or water movement = more DO Water Flow - measurement of water movement Community of Organisms - types of organisms and their adaptations for their zone Sunlight - photic = available sunlight & aphotic = no sunlight; availability of sunlight allows for photosynthesis, chemosynthesis for areas with no sunlight Nutrients - nutrient availability (from floodplains to decaying matter on the floors) All photos from Google Images 9C: Biological, Chemical, Geological, & Physical Components of Aquatic Life Zones Biological - dynamics of aquatic communities in different zones; how organisms work together to create an established ecosystem Chemical - effect of increased pollutants on aquatic communities and water chemistry of each zone (salinity & dissolved oxygen) Geological - topography of seafloor, lake floor, and riverbeds; effects of tectonic events in ocean floor Physical - sunlight availability (photic/aphotic) & temperature (deeper waters have colder temperatures) All photos from Google Images 10C: Adaptations of Fresh vs Marine Organisms Freshwater Adaptations: Tolerance for low dissolved oxygen & low salinity Aerenchyma - enlarged gas space in the stems of wetland plants Strong roots for fast-moving river water Marine Adaptations: Some mammals have blubber to help keep their bodies warm Deep ocean fish have bioluminescence (light organ) that aides in luring prey Salt glands that excrete salt (sharks, rays, skates, some marine reptiles & birds All photos from Google Images