bio

Ecology Study Guide Modules 2, 3, 4 & 5

Definition: Decomposers are organisms that break down dead or decaying organisms, facilitating nutrient recycling within ecosystems.
Function in Ecosystem: They play a critical role in breaking down organic matter, returning nutrients to the soil, and making them available for primary producers.

Definition: Trophic levels represent the hierarchical stages in a food chain, where organisms are classified based on their source of energy.
Greatest Biomass: The trophic level that typically has the greatest amount of biomass is the primary producers (e.g., plants and phytoplankton), as they convert sunlight or inorganic substances into energy through photosynthesis.

Ultimate Source: The ultimate source of energy in any ecosystem is the Sun, as it provides the energy necessary for photosynthesis, which supports all other trophic levels.

Density-Dependent Factors: These are factors whose effects on the size or growth of the population vary with the population density (e.g., competition, predation, disease).
Density-Independent Factors: These factors impact the population size regardless of its density (e.g., natural disasters, climate changes).

Definition: A symbiotic relationship is the interaction between two different organisms living in close physical proximity, often to the advantage of both (mutualism) or one (commensalism and parasitism).

Definition: Pioneer species are the first organisms to colonize previously disrupted or damaged ecosystems; they are typically hardy organisms like lichens or certain grasses.

Primary Ecological Succession: This is the gradual process of change and replacement in a community that occurs in a lifeless area where soil has not yet formed (e.g., after a volcanic eruption).
Secondary Ecological Succession: This process occurs in areas where a biological community has already existed but has been disturbed (e.g., after a forest fire). Soil remains intact, allowing for quicker recovery than primary succession.

K-Strategist Species: These species are characterized by lower reproductive rates, longer lifespan, and higher parental care (e.g., elephants, humans).
r-Strategist Species: These species have high reproductive rates, shorter lifespans, and little parental care (e.g., insects, rodents).

Purpose: Age structure graphs show the distribution of various age groups in a population, helping predict growth trends and potential social and economic implications.
Reading Age Structure Graphs: Look for the shape (pyramid vs. rectangular), which indicates population growth rates (rapid, stable, or declining).

Definition: The carrying capacity is the maximum number of individuals in a species that an environment can sustain indefinitely without degrading the environment.

Definition: Biodiversity refers to the variety and variability of life on Earth, encompassing species diversity, genetic diversity, and ecosystem diversity.
Extinction: Extinction is the end of an organism, characterized by the disappearance of a species when the last member dies.
Genetic Diversity: This is the total number of genetic characteristics in the genetic makeup of a species, crucial for survival and adaptability.
Species Diversity: Refers to the variety of species within a region, including the number of species and the distribution of individuals among those species.
Ecosystem Diversity: Refers to the variety of ecosystems that exist within a particular geographical area or the entire planet.

Direct Economic Value: This includes tangible benefits like resources such as food, medicine, and tourism. For example, forests provide timber and non-timber products.
Indirect Economic Value: This refers to non-tangible benefits like ecosystem services such as pollination, climate regulation, and water filtration. An example is wetlands providing flood protection and water purification.

Definition: Natural resources are materials or components that can be found within the environment that can be exploited for economic gain.
Types: They can be renewable (naturally replenished) or non-renewable (limited supply).

Acronym Meaning: HIPPCO stands for Habitat destruction, Invasive species, Pollution, Population growth, Climate change, and Overexploitation.
Impact: These factors threaten biodiversity, impacting species survival, ecosystem balance, and human wellbeing.

Definition: Habitat fragmentation is the process where a large, continuous area of habitat is divided into smaller, isolated patches, often due to human activity (e.g., urban development, agriculture).

Definition: Biological magnification refers to the increasing concentration of toxic substances within each successive link of the food chain, affecting top predators the most due to their higher dietary intake of contaminated organisms.

Renewable Resources: Resources that can be replenished naturally over time (e.g., solar energy, wind energy, fish stocks).
Non-Renewable Resources: Resources that are finite and cannot be replenished within a human timeframe (e.g., fossil fuels, minerals).

Definition: Sustainable use refers to the management of resources in a way that meets current human needs without compromising the ability of future generations to meet their own needs.

Methods Include: Establishing protected areas, restoring habitats, sustainable resource management, and reducing pollution to maintain healthy ecosystems and species diversity.

Definition: These areas are particularly rich in biodiversity and are under threat from humans, often requiring focused conservation efforts.

Definition: Endemic species are species that are native to a specific geographic area and are found nowhere else in the world, often vulnerable to extinction.

Methods of Restoration: Reforestation, wetland rehabilitation, and the removal of invasive species. It aims to recover ecological integrity and enhance biodiversity.

Definition: Bioremediation is the process of using living organisms, typically microbes, to remove or neutralize contaminants from soil and water, aiding in restoring ecological balance and health.