Unit 1 Apes

Ecosystem

a system of interacting living (biotic) and nonliving (abiotic) components

Biotic

living components of an ecosystem, such as snakes, owls, and cactus

Abiotic

nonliving components of an ecosystem, such as rocks, temperature, and wind

Ecological niche

The specific & unique role of a species within its habitat

Ecosystem Dynamics

Two Key Processes: Energy and Matter

Energy flow

how energy flows into ecosystems (usually from sunlight) and is transferred through trophic levels from producers to consumers

Matter recycling

Matter, including nutrients and elements, is continuously recycled in ecosystems between biotic and abiotic factors.

Limiting resource

Any resource in the ecosystem where demand is greater than supply.

Intraspecific Competition

Competition that occurs within the same species.

Interspecific Competition

Competition that occurs between different species.

Competitive Exclusion Principle

Two species cannot occupy the same niche; one species will outcompete the other leading to local extinction or displacement of the less competitive species.

Resource partitioning

Process where different species in a community utilize distinct resources to minimize competition.

Realized Niche

Fundamental niche redefined into a smaller niche because of Competitive Exclusion Principle and Resource Partitioning.

Symbiosis

Close, long-term interactions between two species.

Mutualism

+/+ interaction where both species benefit.

Commensalism

+/o interaction where one species benefits and the other is unaffected.

Parasitism

+/- interaction where one species benefits and the other is harmed.

Predator-Prey Interactions

Regulates populations; predator and prey populations control each other's size leading to boom and bust cycles.

Negative feedback loop

A process that counteracts change, promoting stability.

Keystone species

Species that have a disproportionately higher impact on the structure and diversity of an ecosystem.

Trophic cascade

Changes in the population of one species cause cascading effects throughout the food chain, impacting multiple species and ecosystem dynamics.

Ecosystem engineers

Species that modify their ecosystem in such a way that other organisms rely on the changes to live or thrive.

Indicator species

Species sensitive to environmental changes that signal the condition of an ecosystem.

ATP (adenosine triphosphate)

The usable energy currency in all life.

Cellular respiration

How cells make ATP using glucose and oxygen, producing carbon dioxide and water.

Photosynthesis

The process where energy from the sun is used to convert gaseous carbon into glucose.

Producers/Autotrophs

Organisms that can perform photosynthesis, such as plants, algae, and cyanobacteria.

Consumers

Organisms that eat other organisms; includes herbivores, omnivores, carnivores, detritivores, and decomposers.

10% rule

Only 10% of energy passes to the next trophic level; 90% is lost as heat.

Food chain

Model of one linear flow of energy within a food web.

Biomass pyramids

Usually mirror energy pyramids because of the second law of thermodynamics.

Food Webs

Interconnected food chains that show the complex feeding relationships within a community.

Biodiversity

The variety of life in an ecosystem; more diversity leads to less impact from species loss.

Temperature decreases with latitude

As distance from the equator increases, temperature generally decreases.

Insolation

Incoming solar radiation, which is highest at the equator where sunlight hits directly.

Atmospheric circulation

The uneven heating of Earth that drives global rainfall patterns.

Global wind belts

Three major areas where warm, moist air rises and cool, dry air sinks.

Tropic of Cancer

Located at 0°

Tropic of Capricorn

Located at 30°

Nonmineral resources

Resources such as water, timber, and fertile soil that depend on a biome's climate, geography, and nutrient availability.

Soil fertility

The ability of soil to support plant growth, highest when there is a steady supply of organic material being broken down into nutrients.

Moisture

Essential for organisms to break down organic material.

Heat

Speeds up the decomposition process of organic material.

Season

Causes growth and dieback cycles, leading to more organic matter.

High biomass + fewer trees

Creates more organic matter entering the soil, but trees lock nutrients in their trunks.

Most fertile soil

Characterized as dark and fluffy.

Least fertile soil

Characterized as light and dry.

Dynamic biomes

Biomes that change over time due to factors like ice ages, tectonic shifts, and mass extinctions.

Modern shifts in biomes

Linked to climate change, with tundra shrinking and deserts expanding.

Tropical Rainforest

Located at 0 degrees (equator), it has the highest annual rainfall (200-400 cm per year) and warm temperatures year-round (~25-30°C).

High humidity

Leads to low temperature fluctuation between night and day in tropical rainforests.

Soil in tropical rainforests

One of the least fertile soils on Earth.

Rapid decomposition

Nutrients are quickly absorbed by plants, leached away by rain, and minerals accumulate in acidic conditions.

Acidic soil

Makes it harder for plants to absorb key nutrients like calcium and magnesium.

Epiphytes

A plant that grows on another plant but is not parasitic.

Desert

Located 30 degrees north and south of the tropic of cancer and capricorn, characterized by very low precipitation (<25 cm per year) and high year-round temperatures.

Xerophytes

Plants such as cacti and succulents that have adaptations for drought, heat, and sand.

Tropical Grassland: Savannah

Characterized by warm temperatures year-round and distinct wet and dry seasons.

Moderately fertile soil

Clay-rich soil that retains moisture longer, often reddish in color.

Temperate Grassland

Includes regions like the Russian Steppes and Great Plains, with moderate precipitation (25-75 cm) and fertile soil ideal for crops.

Natural fires

Occur regularly in temperate grasslands, recycling nutrients and preventing tree growth.

Temperate Seasonal Forest

Characterized by four distinct seasons and moderate to high precipitation (75-150 cm).

Broadleaf deciduous trees

Trees that shed leaves in winter to conserve water.

Taiga

The largest biome, located at 60°N of the equator, with long, cold winters and short, mild summers.

Coniferous trees

Trees like spruce, fir, and pine that keep their needle-like leaves year-round.

Tundra

A biome with very low precipitation, long harsh winters, and a short cool growing season.

Permafrost

Prevents deep roots and slows decomposition, leading to low fertility soil.

Temperate Rainforest

A small, coastal biome found near oceans with high precipitation (200-350 cm/year).

Primary Productivity

The rate at which producers convert sunlight into chemical energy (glucose) through photosynthesis.

NPP

Net primary productivity, calculated as NPP = GPP - R, where GPP is gross primary production and R is cellular respiration.

GPP

Gross primary production, the energy stored during photosynthesis.

R

Cellular respiration, the energy used by plants to live and grow.

Nutrients

Essential for plant growth, especially nitrogen and phosphorus.

Glucose

The chemical energy used for growth, reproduction, and energy storage.

Oxygen

Released through plant tissues such as leaves during photosynthesis.

Chloroplasts

Organelles in plants that absorb blue and red wavelengths of light for photosynthesis.

Aquatic biomes

Light is limiting for photosynthesis, with red light absorbed within 1 meter and blue light penetrating deepest.

Photic zone

The upper layer of water in a body of water that receives enough sunlight for photosynthesis.

Nutrient poor

Surface waters that lack essential nutrients, limiting productivity.

Coastal upwelling zones

Areas where deep, cold, nutrient-rich water rises to the surface, supporting high biodiversity and productivity.

Watershed

An area of land where all rain and snowmelt drains to a common body of water.

Salinity

The concentration of salt in water, affecting the type of aquatic life that can thrive.

Temperature

Cold water holds more oxygen, while warm water allows oxygen to diffuse out.

Light availability

The amount of light that penetrates water, affecting photosynthesis rates.

Turbidity

The cloudiness of water caused by suspended particles, affecting light penetration.

pH

A measure of acidity or basicity of water, affecting aquatic life; ranges from acidic (6.8) to basic (8.2).

Freshwater biomes

Ecosystems that contain water with low salt concentration, important for drinking water and irrigation.

Lentic systems

Standing water bodies like ponds and lakes, zoned by depth and light.

Oligotrophic lakes

Deep, clear lakes with low nutrients and low productivity.

Mesotrophic lakes

Lakes with moderate depth, nutrients, and productivity.

Eutrophic lakes

Shallow lakes with high nutrients and high productivity.

Marine biomes

Aquatic ecosystems that make up 97.5% of Earth's water, primarily saltwater.

Estuaries

Areas where freshwater meets saltwater, characterized by high productivity and biodiversity.

Coral reefs

Marine ecosystems found in warm, shallow waters, known for high productivity and biodiversity.

Open ocean

The largest biome on the planet, mostly nutrient poor with low NPP per area.

Hydrologic cycle

The continuous movement of water within the Earth and atmosphere.

Biogeochemical cycle

The cycling of matter between the biotic and abiotic parts of ecosystems.

Earth's spheres

The four divisions of Earth: hydrosphere, geosphere, biosphere, and atmosphere.

Short residence time

The atmosphere for water.

Sink/Reservoir

Long residence time.