Ecosystems Study Guide

Ecosystem Basics

Individual Organism: A single organism, e.g., an elk.
Population: A group of individuals of the same species, e.g., an elk herd.
Community: All living organisms in a particular area.
Ecosystem: Comprises all living and non-living things in an area, including plants, animals, rocks, soil, water, and air.
Biome: A large area with similar climate conditions that influence the species of plants and animals found there. Example: Tropical rainforest.

Mutualism: A relationship that benefits both organisms. Example: Coral reefs.
Competition: Interaction where organisms compete for resources like food or shelter, which limits population size.
Predation: One organism uses another as an energy source (includes hunters, parasites, and herbivores).
Commensalism: A relationship that benefits one organism without impacting the other. Example: Birds nesting in trees.

Resource Partitioning: Different species use the same resource differently, reducing competition and limiting population sizes.
Temporal Partitioning: Species use the same resource at different times (e.g., wolves and coyotes hunting at night vs. day).
Spatial Partitioning: Species using different areas of the same habitat (e.g., plants with different root lengths).
Morphological Partitioning: Resources are utilized based on evolved body features differences among species.

Biome Characteristics: Biomes are characterized by average yearly temperature and precipitation.
Adaptation: The community of organisms in a biome is uniquely adapted to live in that environment. Example: Camels and cacti in the desert.

Biomes are defined by annual temperature and precipitation averages.
A biome chart can predict the locations of biomes on Earth:
- Tundra & Boreal: Higher latitudes (60° and above).
- Temperate: Mid-latitudes (30° to 60°).
- Tropical: Closer to the equator.
Latitude affects temperature and precipitation, resulting in a predictable pattern of biomes.

A graphical representation that shows average climate conditions by month.
Hybrid line-bar graph format (temperature usually shown as a line, precipitation as bars).

Biomes can shift in location due to climate change (e.g., warming climates pushing boreal forests north as permafrost thaws).

Depth: Influences sunlight penetration and photosynthesis potential.
Temperature: Warmer water holds less dissolved oxygen, limiting aquatic organisms.
Salinity: Levels of salt in water determine species survivability and water usability (freshwater vs. estuary vs. ocean).
Flow: Affects the types of plants and organisms that survive and the amount of oxygen in water.

High oxygen levels due to water flow and mixing with air. Carry nutrient-rich sediments leading to fertile soils.

Standing bodies of freshwater, key drinking water sources.
- Littoral Zone: Shallow water with emergent plants.
- Limnetic Zone: Area where light penetrates for photosynthesis; no rooted plants, only phytoplankton.
- Profundal Zone: Too deep for sunlight, thus no photosynthesis.
- Benthic Zone: Murky bottom where invertebrates live; nutrient-rich sediments.

Areas with soil submerged/saturated for at least part of the year and suitable for emergent plants (e.g., cattails, lily pads).
Benefits of Wetlands:
- Store excess water during storms, reducing floods.
- Recharge groundwater through rainfall absorption.
- Roots filter pollutants from drainage water.
- High plant growth due to nutrient-rich sediments.

Found in warm, shallow waters beyond shorelines; they are the most diverse marine biome on Earth.
Features a mutualistic relationship between coral and algae:
- Coral utilizes CO₂ from the ocean to create calcium carbonate for its exoskeleton and provides CO₂ to algae.
- Algae, in turn, provide sugars (energy) to coral via photosynthesis.

Characterized by low productivity per area, as primarily algae and phytoplankton survive.
Photic Zone: Area where sunlight reaches and photosynthesis occurs.
Aphotic Zone (Abyssal): Too deep for sunlight; crucial as algae and phytoplankton produce a significant amount of Earth's oxygen and absorb CO₂.