Fundamental Ecological Concepts
- Biosphere: All living organisms inhabiting the planet at a given moment.
- Ecosystem: A set of living organisms inhabiting a specific place (biocenosis), the physical and chemical factors of that location (biotope), and the interactions produced between them.
- Abiotic Factors: Physical and chemical factors that affect living organisms and the environment they inhabit, such as temperature, light, medium, water, and salinity.
- Limiting Factor: Abiotic factors that limit the ability of a specific species to develop.
- Ecological Valence: Tolerance interval of a species regarding one or various abiotic factors.
- Euryoecious Species: Species that have a very large tolerance interval.
- Stenoecious Species: Species that cannot survive beyond a very strict tolerance interval.
- Medium: The environment where living organisms move and live within an ecosystem, maintaining exchanges of matter and energy.
Population Dynamics
- Population: All individuals of the same species living in an ecosystem at a specific moment capable of reproducing.
- Effective Population: Total number of individuals that form part of the population.
- Density: Number of individuals per unit of surface or volume.
- Natality (tn): Number of births in a determined period of time.
- Mortality (tm): Number of deaths in a determined period of time.
- Immigration Rate: Number of individuals that incorporate into the population.
- Emigration Rate: Number of individuals that leave to abandon the population elsewhere.
- Biotic Potential: Maximum reproductive capacity under optimal conditions without limitations like food shortages, diseases, or predators, resulting in maximum birth rate and minimum mortality.
- Environmental Resistance: Set of abiotic and biotic factors that limit population growth.
- Carrying Capacity: Maximum number of individuals that can be maintained under determined environmental conditions.
Trophic Webs and Energy Flow
- Trophic Chain: Models indicating the food relationships and energy flow between different organisms, where each organism occupies a specific trophic level.
- Saprophages: Organisms that utilize and ingest dead organic matter.
- Scavengers: Organisms that feed on recent or shortly decomposed carcasses.
- Dung Feeders: Organisms that feed on excrement.
- Biomass: Quantity of living or dead organic matter at any trophic level.
- Primary Production: Quantity of organic matter, alive or dead, at the primary producer level.
- Gross Primary Productivity (GPP): Biomass synthesized by producers per unit of time.
- Net Primary Productivity (NPP): Biomass remaining after discounting producer respiration, representing food at the disposal of herbivores.
- Secondary Production: Production of biomass by consumers and decomposers per unit of time and surface.
- Gross Secondary Productivity: The percentage of total assimilated food.
- Net Secondary Productivity: Gross secondary productivity minus respiration.
- Estuaries: Semi-enclosed coastal areas where freshwater mixes with saltwater, serving as important marine nursery areas.
- Coral Reefs: Calcareous exoskeleton formed by coral animals, red algae, and mollusks, growing between 1 and 100 cm per year in waters where temperatures never drop below 16°C.
- Rule of the 10%: Around only 10% of the energy from one trophic level is passed on to the next trophic level.
- Productivity: The ratio of production to biomass per unit of surface, indicating the efficiency of energy transfer from one level to another.
- Production: The increase in biomass experienced by an ecosystem or trophic level per unit of surface and time.
- Renewal Time: The time it takes for a trophic level to renew its biomass.
- Ecological Efficiency: Measures how much energy is lost or accumulated at each trophic level in an ecosystem.
Ecological Pyramids
- Pyramid of Numbers: Represents the number of individuals at each trophic level.
- Pyramid of Biomass: Represents the total mass of each trophic level.
- Pyramid of Energy: Represents the quantity of energy that exists at each trophic level and the energy transferred to the next production level.
