Ecology

The word ‘___ was first used by Ernest Haeckel in 1869. He describe __ as the scientific study of the interactions between organisms and their environment. The word is derived from the Greek oikos, meaning ‘home’. __ might therefore be thought of as the study of the ‘home life’ of living organisms

In 1972, he define ecology as the scientific study of interactions that determine the distribution and abundance of organisms. Notice that it’s do not use the word environment. It is necessary to define the word

Ecologist have identified four fundamental levels of the organization to study the interactions between organisms and their environment.

a single species, at the level of organisms, ecology deals with how individual organisms are affected by (and how they affect) their environment.

A group of individual with the same species in a given area. Populations of different species in an area do not function independently of each other. They interact with each other. Hence, the next, more complex level of organization is.

made up of interacting populations of different species within some defined geographical area.

the interacting system made up of all the living and non-living components in a physically defined space. Because an ecosystem is a system, it has boundaries.

the highest level of organization, it is an ultimate ecosystem. It includes all ecosystems present on the earth ̶ environment on a planetary scale.

is a basic functional unit of ecology comprising of all organisms in a particular place interacting with one another with their physical environment and interconnected by an ongoing flow of energy and a cycling of nutrients.

Two basic components of structure of an ecosystem

living organisms in an ecosystem can be classified as either producers or consumers, depending on how they get their food (PRODUCERS, CONSUMER, DECOMPOSERS)

all the physical and chemical factors that influence living organisms, like air, water, soil, rocks etc. Thus, it is an assemblage of organic and inorganic substances present in an ecosystem. Also various climatic factors are also part of this.

is a fundamental process which occurs in all ecosystems. Energy is defined as the capacity of work. It is the basic force responsible for all metabolic activities. The flow or movement of energy through a series of organisms in an ecosystem is called energy flow. The energy flows from producer to top consumers in unidirectional form.

The transfer of food energy from producers through a series of organisms that consume and are consumed

Food chains usually consist of producers :

Types of Food Chain

starts from a base of green plants and goes on to herbivores and finally to carnivores.

starts from a base of dead organic matter.

Types of ecological pyramid

in which the numbers of individual organisms are depicted. (Upright and Inverted pyramid of number)

based on the total dry weight or other measures of the total amount of living matter.

In which energy assimilated and/or productivity at successive trophic levels are use.

Level of organization of matter in nature:

7 environmental principle