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

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 ZonationPhotic Zone-- Enough sunlight for photosynthesisAphotic 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 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 shoreOccupied by phytoplankton &cyanobacteria

2 Types of Lakes

Oligotrophic 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