Basic ecological principles

Basic Ecological Principles

Understanding Ecology

• Ecology is the science of relationships between living organisms and their environments.
• The term was coined by the German zoologist Ernst Haeckel in 1866.
• It involves studying individual organisms, populations, communities, ecosystems, and the biosphere as a whole.

Levels of Ecological Organisation

• The fundamental levels include: organism, population, community, ecosystem, and biosphere.
• An organism is any individual living thing. It can be a plant, animal, fungi, or microorganism.
• A population is a group of individuals of the same species living in the same area.
• A community consists of multiple populations of different species living together.
• An ecosystem includes all communities in a specific area, along with non-living (abiotic) factors such as weather and geography.
• The biosphere is the summation of all ecosystems on Earth - it encompasses every place where life exists.

Energy Flow and Nutrient Cycling

• Energy enters each ecosystem via the sunlight absorbed by plants and certain types of bacteria.
• Through photosynthesis, these organisms convert sunlight into chemical energy (glucose), which is then used by other organisms.
• Herbivores (plant eaters) form the first trophic level of consumers, followed by carnivores (meat eaters), and finally decomposers and detritivores (organisms that consume dead organic material).
• Nutrients cycle through various forms and places through the nutrient cycle.
• This cycle includes processes such as decomposition, respiration, combustion, and leaching.

Population Dynamics

• Population dynamics involve understanding how population sizes change in response to various factors.
• This can include birth rates, death rates, immigration, and emigration.
• Population density is defined as the number of individuals of a species in a particular unit of space.
• A carrying capacity is the maximum number of individuals a habitat can support.
• Factors such as predation, disease, and food availability can affect population density and carrying capacity.

Interactions Among Species

• Predation, competition, mutualism, and commensalism are different types of interactions that can take place between species.
• Predation occurs when one organism eats another.
• Competition happens when two or more species vie for the same limited resource.
• Mutualism is a type of symbiosis where both species benefit.
• Commensalism is another form of symbiosis, where one species benefits and the other is unfazed.

The Influence of Human Activity on Ecosystems

• Human activities, such as deforestation, hunting, and pollution, have significant impacts on ecosystems.
• Conservation is a practice that aims to protect, preserve, and manage species and their habitats to prevent endangerment and extinction.
• Conservation techniques can include establishing protected areas (national parks), practicing sustainable use of resources, and implementing species recovery plans.