Terrestrial Biomes & Aquatic Ecosystems

1. Terrestrial Biomes & Aquatic Ecosystems

2. LARGE ECOSYSTEMS • Human-classified divisions • Same types of climates = similar types of vegetation • Similar vegetation = similar biome • ≠ exact same flora, fauna, or physical abiotic makeup • Terrestrial Ecosystems or Biomes • 10 Types • Aquatic Ecosystems • 3 types

3. TERRESTRIAL BIOMES

4. Terrestrial Biomes • Large area characterized by its climate and the plants and animals that live in the area – contains related ecosystems. Tundra Chaparral Polar Ice Temperate Grassland Taiga/Coniferous Forests Savanna Mountainous regions Desert Temperate Deciduous Forest Tropical Rainforest

5. Tundra

6. Tundra (Polar and Alpine) • Tundra = “treeless plain” • Flat terrain with low shrubs, grasses, sedge, mosses, lichens; low biodiversity • One-fourth of Earth’s terrestrial surface • Present in northernmost latitudes (≥ 60° N) • Desert-like rainfall (30-50 cm or 12-20 in per year) but bogs and marshes in summer rainy season due to permafrost

7. Tundra (cont’d) • Permafrost – condition of permanent frozen soil beginning ~ 1 meter (m) below surface and extending down to 500 m • Water can not drain • Plants produce in short 50-day season • Year-round: Arctic lemmings, hares, foxes • Summer migratory animals seeking food • No reptiles or amphibians

8. Taiga

9. Taiga • Also known as the Boreal or northern forests – covered with coniferous trees such as firs, pines, spruces, and cedars (dominant vegetation) – located south of tundra • Largest biome on Earth; low biodiversity • Winters: very cold and snowy • Summers: warm, rainy, and humid • Large mammals, fur-bearing animals • Very few reptiles and amphibians

10. Temperate Deciduous Forest

11. Temperate Deciduous Forest • Majority of eastern US, as well as continental western Europe and east Asia • Deciduous trees (with seasonal leaf loss) including maples, beeches, oaks, and hickories, as well as understory of woody shrubs and vines and herbaceous plants • Much precipitation (75 to 200 cm /yr) (3-8x that of tundra) • Milder winters, warm to hot summers • Great variety of animals, including reptiles and amphibians

12. Temp. Deciduous Forest (cont’d) • Abundance of pines (evergreens) in the SE US is only temporary • “Succession” – as ecosystem “ages,” new flora species replace previous ones (e.g., grass to low shrubs and vines to evergreens to hardwoods); as flora change so will fauna • Here, climax successional stage is oak/hickory forest

13. Temperate Grassland

14. Temperate Grassland • Areas of predominantly tall, mixed, or short grasses sandwiched between temperate deciduous forests and deserts • Annual precipitation of 25-100 cm • Extremely fertile soil (US Midwest farms) • Natural grasslands destroyed for agriculture; very little left in world • Short grass prairie – crops and cattle

15. Savanna • Subtype of grassland: tropical grassland in Southern Hemisphere (Africa, South America, and Australia) • Seasonal drought, warm climate, dotted with stands of trees, and home to typical large mammals (e.g. in Africa, elephants, giraffes, zebras, lions, spring boks, cape buffalo, etc.)

16. Desert

17. Desert: “Got Water?” • Desert – area receiving < 25 cm annual precipitation; evaporation > precipitation • Deserts may be cold, temperate, or hot • Flora and fauna specialized to survive with little water – collect and conserve • Soils poor because lack of water = very little biomass, or net productivity, low organics = inability to hold water • Concentration of inorganic salts high

18. Tropical Rainforest

19. Tropical Rainforest • Large warm equatorial areas, abundant annual precipitation (200-450 cm and even to 1000 cm for some) with high biomass productivity and biodiversity • 7% of Earth’s land mass under massive destruction; can not be replaced • Poor, acidic soil: plants uptake quickly-decomposed organic nutrients

20. Polar Ice and Mountains • Polar Regions: • Cold, dry, devoid of terrestrial plant life • Animals capable of living in frigid conditions and basis of survival on highly productive marine ecosystem • Mountains: • Increase in altitude similar to northern latitudes (cooler climate and conifers) • Rain shadow on lee side (desert area)

21. Chaparral • Not a grassland • Punctuated with low-growing evergreen shrubs, pines, and scrub oaks • Lands on Western coast lines with Mediterranean type climate (wet mild winter/ hot dry summer, ocean winds)

22. Biome Ecological Concerns • Tundra/Taiga– ore mining, oil drilling, ecosystem fragmentation, global warming/species changes • Temperate Deciduous Forests – human destruction for resources and population • Temperate Grasslands – very little remaining, non-native grass species; agriculture • Deserts – In US, human encroachment • Tropical Rain Forests - human destruction for resources and population; expansive loss of species, biomass net productivity

23. Aquatic Ecosystems • Marine • Intertidal Areas • Coral Reefs • Estuaries – fresh water from streams and rivers spills into oceans • Sargasso Sea (middle of Atlantic Ocean – floating rafts of algae called sargassum) • Polar Ice – Arctic Ocean and ocean around Antarctica Freshwater • Stream and River; Pond and Lake Wetland • Marshes and Swamps

24. Marine Ecosystems Photic zone = surface to 100 m down; photosynthesis occurs Saltwater oceans cover ¾ of Earth’s surface. Fig. 32.34

25. Marine Ecosystems, cont. • Intertidal Zone: the place where the ocean meets the land; area is exposed to the air for part of the day; sea grasses, periwinkle snails, and herons are common in intertidal mudflat; sea stars and anemones live on rocky shores; clams, crabs, snails, and conchs are common on sandy beaches • Neritic Zone: Ocean floor starts to slope downward as you move away from shore; water is warm and receives a lot of sunlight; plankton and seaweeds common; sea turtles, dolphins, corals, sponges, and colorful fishes dominate – CORAL REEFS!

26. Marine Ecosystems, cont. • Oceanic Zone: Sea floor drops sharply; contains deep water of open ocean; many unusual animals are adapted to this zone, such as whales, squids, fishes that glow, sharks, etc. • Benthic Zone: Ocean floor; deepest parts do not get any sunlight and are very cold; animals, such as fishes, worms, sea urchins, and crabs, have special adaptations to the deep, dark water

27. Marine Ecosystem ESTUARY - • Coastal point of contact between freshwater and saltwater; mix = “brackish” water • Constant mixing stirs up nutrients for photosynthesizers; animal life abundant • As productive as tropical rainforests and coral reefs • Concerns: • Although protected, human pollution and encroachment threaten health of estuaries

28. Marine cont’d • Abundance of life is generally greater: • Nearer coast (intertidal zone) due to stirring action of waves and nearer surface from light • In polar regions rather than tropical regions (abundant food – plankton - for large organisms) • In tropical coral reefs along shallow coastlines

29. Marine cont’d • Ecological Concerns: • Overfishing and industrial fishing techniques that destroy deep water habitats • Human pollution of the coastal waters (sewage, construction erosion, chemical use, etc.) • Human physical destruction of sensitive ecosystems such as coral reefs, tidal pools

30. Freshwater Ecosystems Inland freshwater streams, ponds, and lakes cover 2.1% of Earth’s surface.

31. Freshwater Ecosystems Littoral Zone - area of water closest to edge of lake or pond; cattails, rushes, algae, water lilies; small animals, snails, insects, clams, worms, frogs, salamanders, turtles, fish, and snakes Open-Water Zone – the zone of a pond or lake that extends from the littoral zone and that is only as deep as light can reach – bass, lake trout, and other fishes Deep-Water Zone – the zone of a lake or pond below the open-water zone, where no light reaches – carp, catfish, worms, crustaceans, fungi, and bacteria

32. Freshwater cont’d • Natural lake nutrient concentrations (phosphorus often is limiting factor) • Shallow, nutrient rich = eutrophic • Abundant aquatic photosynthesis and animals (cloudy, murky water) • Occurs naturally over long periods of time • Deeper, nutrient poor = oligotrophic • Few nutrients to aid photosynthesis, little animal life (clear water)

33. Freshwater Concerns • Artificial eutrophication of lakes: nutrient rich sewage, fertilizers, construction erosion, etc. feed algae • Algal bloom leads to accumulation of dead algae; decomposition by oxygen-using bacteria; fish kills • Clean Water Act has helped, but battle not over (Pollutants regulated under the CWA include "priority" pollutants, including various toxic pollutants; "conventional" pollutants, such as biochemical oxygen demand (BOD), total suspended solids (TSS), fecal coliform, oil and grease, and pH; and "non-conventional" pollutants, including any pollutant not identified as either conventional or priority. The CWA regulates both direct and indirect discharges. )

34. Wetland • Land remaining wet for at least part of the year (bog, marsh, swamp, tidal marshes) and very productive • Most are inland, freshwater • Soils and plants can capture pollutants, act as wastewater system and clean up • Play important role in flood control • Concerns: • Federal protection requires restoration, but many destroyed • Loss of migratory bird habitat

35. Marshes and Swamps • Marshes • Treeless wetland ecosystem where plants grow; found in shallow areas along shores of lakes, ponds, rivers, and streams; grasses, reeds, bulrushes, wild rice, muskrats, turtles, frogs, and birds dominate • Swamps • Wetland ecosystem in which trees and vines grow; found in low-lying areas and beside slow-moving rivers; flooded part of the year; willows, bald cypresses, oaks, poison ivy, water lilies, orchids, fish, snakes, and birds dominate