Introduction to Ecology and Biomes

Ecology

The study of interactions between living organisms and their environment.

Organism level

The level of study focusing on individual living entities, such as each pine tree or zebra, and their adaptations to specific habitats.

Population level

The level of study that examines all individuals of a species in an area and how population sizes change over time.

Community level

The level of study that encompasses all plant and animal species in a community and the interactions between them and their environment.

Ecosystem level

The level of study that includes all biotic and abiotic components in an area and how nutrients are cycled through organisms and the environment.

Biosphere

The planet earth, encompassing all ecosystems.

Biogeography

The geographic distribution of living things and the abiotic factors that affect their distribution.

Endemic species

Species that are naturally found only in a specific geographic area, usually restricted by size.

Generalist species

Species that can live in a wide variety of geographic areas.

Species distribution patterns

Patterns based on both biotic and abiotic factors affecting the distribution of species.

Biomes

Areas characterized by specific environmental conditions.

Tropical wet forests

Also known as tropical rainforests, found in equatorial regions with stable temperatures and high biodiversity.

Savannas

Grasslands with scattered trees, typically hot with extensive dry seasons, located in Africa, South America, and Northern Australia.

Subtropical deserts

Deserts centered on the tropics of Cancer and Capricorn, characterized by very dry conditions and high daytime temperatures.

Chaparral

Also called scrub forest, found in California and Mediterranean regions, with most rain falling in winter and plants adapted to periodic fires.

Temperate grasslands

Known as prairies in North America and steppes in Eurasia, characterized by pronounced temperature fluctuations and dense grasses.

Temperate forests

The most common biome in Eastern North America, Western Europe, and Eastern Asia.

Temperate forests

Forests with defined growing seasons during spring, summer, and fall.

Deciduous trees

Dominant plants in temperate forests.

Boreal forests

Also known as taiga or coniferous forests, characterized by large amounts of pine trees.

Location of Boreal forests

Found south of the Arctic Circle, in most of Canada, Russia, and Northern Europe.

Climate of Boreal forests

Cold, dry winters punctuated by short, cool, wet summers.

Precipitation in Boreal forests

Most precipitation comes in the form of snow.

Cold-tolerant coniferous plants

Evergreens that require less energy from the sun to heat needle-like leaves.

Energy and biodiversity in Boreal forests

Less energy and biodiversity than temperate and tropical wet forests.

Arctic tundra

Located north of boreal forests throughout Arctic regions.

Growing season in Arctic tundra

Plants have very short growing seasons of 10-12 weeks.

Daylight in Arctic tundra

During the growing season, there are almost 24 hours of daylight, leading to rapid plant growth.

Biodiversity in Arctic tundra

Plants generally low to the ground, with low biodiversity and energy production.

Annual precipitation in Arctic tundra

Very low annual precipitation.

Permafrost

Soil in a perennially frozen state.

Aphotic zone in oceans

Majority of the ocean is aphotic, meaning no photosynthesis occurs due to lack of light.

Challenger Deep

Deepest part of the ocean located in the Mariana Trench, measuring 6.8 miles.

Ocean

The largest marine biome.

Intertidal zone

Zone between low and high tide where organisms are adapted to withstand waves and dry periods.

Neritic zone

Area from the intertidal zone to the edge of the continental shelf, where light can penetrate.

Continental shelf

The change from the 'shallow end' to the 'deep end' of the ocean.

Pelagic zone

Open water area of the ocean.

Thermal stratification

Mixing of warm and cold waters in the ocean.

Aphotic zone

Layer too deep to see any photosynthesis, where light stops and does not go deeper.

Abyssal zone

Deepest part of the ocean, characterized by very cold, high pressure water and nutrient richness.

Benthic realm

Deep water region beyond the continental shelf, rich in nutrients due to falling dead organisms.

Lakes and ponds

Freshwater bodies that experience thermal stratification in summer.

Thermocline

The layer that separates warmer water at the top from cooler water at the bottom in lakes and ponds.

Photic zone

Layer in lakes and ponds where light can penetrate.

Phytoplankton

Photosynthetic organisms that live in the photic zone.

Zooplankton

Organisms, such as rotifers and adult crustaceans, that eat phytoplankton.

Bacteria and fungi

Microorganisms that break down dead organisms in aquatic environments.

Nitrogen and phosphorus

Important limiting nutrients for aquatic ecosystems.

Algal bloom

Sharp increase in nitrogen and/or phosphorus leading to a dramatic increase in algae.

Industrial or agricultural waste

Source of nutrient pollution that can lead to algal blooms.

Food chain disruption

A consequence of algal blooms that affects nutrient flow and can produce toxic compounds.

Sargassum

A type of marine seaweed found in the neritic zone.

Plankton

Organisms that float in the water and are a basis of food chains.