Ecology & Biomes

Ecology Def. – Interactions between organisms & the environment Biotic factors Behavior Interaction with other species Biota – all living organisms in an environment Abiotic factors Nonliving components – Temp., water, sunlight, wind Chemical & physical factors

Example: Biotic Factors Behavior is the most important factor for determining distribution of a population Biotic factors are also important Predators or prey may influence ability to survive Kelp (algae) are predated by herbivorous sea urchins & limpets

Biotic & Abiotic Factors

Red Kangaroo distribution? NOTE: Australia is dry in the center, wet in periphery **Highest concentration is found in regions with low precipitation rates **Lowest concentration is found in regions that are cold or hot, but always are wet

Climate Composed of 4 abiotic factors: TWSW (That’s Wat She Waid?) Temperature Water Sunlight Wind Temperature & water = Most Important Limiting Factors (MILFs)

Climate Patterns 2 main climate patterns Macroclimate Microclimate Global, regional or local levels Microclimate Small-scale environmental variations Under a log Tree canopy vs. forest floor

Biomes Def. – the major types of ecosystems that occupy broad geographic regions 2 main Types Aquatic Freshwater Marine Terrestrial Forrests, grasslands, desert, etc.

Aquatic Biomes Vertical Zonation Photic Zone Aphotic zone Benthic zone -- Enough sunlight for photosynthesis Aphotic zone -- Yep, u guessed it Benthic zone -- Bottom of the biome -- Sand, organic sediment, and ooze (inorganic sediment) Detritus -- dead organic matter that falls from photic zone Pelagic zone – open water

Thermocline -- Layer of fast temperature change that separate a uniformly warm upper layer and a uniformly cold deeper layer -- Ocean & most lakes -- Especially seen during summer & winter

Freshwater Biomes Standing bodies of H2O Moving bodies of H2O Lakes & wetlands Moving bodies of H2O Streams, rivers, & estuaries

Freshwater Lakes ONLY Littoral Zone -- Shallow & well-lit waters -- Close to shore  Features rooted or floating aquatic plants Limnetic Zone -- Deep, but well lit waters -- Far from shore Occupied by phytoplankton &cyanobacteria

2 Types of Lakes Oligotrophic Eutrophic Normal, healthy water Nutrient-poor water Oxygen-Rich water Eutrophic Algal blooms Nutrient-rich water Oxygen poor water

Estuaries Transition area between river and sea Complex flow pattern Low-density freshwater lies on top of high- density saltwater