Ecology: Habitats, Niches, and Environmental Components

• Ecology is the study of interactions between organisms and their environment.
• Ecology explains how living organisms affect each other and the world they inhabit.
• The aim of studying ecology is to define Ecology, Habitat, and Niche, describe the environment's components, explain the ten percent law, discuss the level of organization, and create a food chain and food web model

Habitat and Niche

• A habitat is the place where a plant or animal lives.
• A niche is an organism's total way of life.

Environmental Components

• Abiotic factors are the nonliving parts of an organism's environment, like air currents, temperature, moisture, light, and soil.
• Biotic factors encompass all living organisms within an environment.
• All organisms rely on others directly or indirectly for food, shelter, reproduction, or protection.

Levels of Organization

• Ecologists organize an organism's interactions into different levels based on complexity.
• An organism is an individual living entity composed of cells that utilizes energy, reproduces, responds, grows, and develops.
• A population constitutes a group of organisms of the same species that interbreed within the same location and time.
• A community encompasses all populations of different species living in the same place at the same time.
• An ecosystem consists of populations of plants and animals interacting with each other alongside the abiotic components in a given area, whether terrestrial or aquatic.
• A biome refers to a major regional or global biotic community, a super ecosystem defined primarily by the dominant forms of plant life and prevailing climate.

Energy Flow in Ecosystems

• Producers (Autotrophs) manufacture their own food, typically through photosynthesis; plants like the Venus Flytrap exemplify this group.
• Consumers (Heterotrophs) cannot produce their own food and derive energy from consuming other organisms.
• Herbivores consume plants.
• Carnivores consume animals.
• Omnivores consume plants and animals.
• Scavengers consume dead animals.
• Decomposers break down waste and dead organisms, returning raw materials to the environment; examples include bacteria, fungi, and worms.

Food Chains and Food Webs

• Energy enters an ecosystem as sunlight.
• Food chains show a single path of energy flow in an ecosystem.
• The order of the food chain is: Sun -> Producer -> 1st level Consumer -> 2nd level Consumer -> Decomposer.
• Food webs illustrate the energy flow through different organisms in an ecosystem.
• Food webs consist of many overlapping food chains within an ecosystem.
• A food chain describes the feeding relationship between a producer and a single chain of consumers in an ecosystem.

Food Web vs Food Chain

• A food chain is a single linear pathway, while a food web consists of multiple interconnected pathways:
• Food chains decrease stability in ecological communities.
• More complex food webs increase the stability of ecological communities.
• In a food chain, one individual occupies one trophic level, making it less adaptive.
• In a food web, one individual occupies many trophic levels, making it more adaptive.

Ecological Pyramid Models

• A pyramid illustrates the structure of trophic levels in a food chain.
• Types of ecological pyramids are pyramids of numbers, biomass pyramids, and energy pyramids.
• Pyramid of Numbers: Compares the number of organisms at each trophic level in a food chain.
• Biomass Pyramid: Shows the total dry weight of organisms in a food chain
• Energy Pyramid: Illustrates the amount of energy moving from one feeding level to the next in a food chain or web. The greatest amount of energy is available to producers. About 10% of a trophic level's energy is transferred to the next level.

Ecological Relationships

• Symbiosis describes any relationship or interaction between two dissimilar organisms.
• Predation involves one organism consuming another, generally smaller, organism.
• Mutualism is a form of symbiosis where both organisms involved benefit.
• Commensalism is a type of symbiosis where one member benefits while the other remains unaffected.
• Parasitism is a form of symbiosis where one member benefits at the expense of the other.

Ecological Succession

• Ecological succession is the process by which an ecosystem recovers from an abiotic disaster.
• Stages exist, and each has distinct species.
• Primary succession occurs when the ecosystem has suffered a total loss; species from the outside then recolonize.
• Secondary succession occurs when the ecosystem has been disturbed but not totally wiped out, allowing its own members to recover the disturbed space.

Human Activities

• Human activities are capable of changing ecosystems.
• Habitat loss, often for building places for humans, is a significant human activity that causes problems.