Category: Ecology & Environment
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Soil as Ecological Factor
Introduction Soil consists of weathered layer of Earth’s crust with products of decay of living organisms intermingled. In soil, thus, abiotic & biotic components are intimate. Soil is considered to be chief organizing centre for land ecosystems. Pedosphere: Outermost layer of earth that is composed of soil & subject to its formation. Pedogenesis: Process of…
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Principles of Limiting Factors
Liebig’s Law of Minimum History: The concept was first provided by J. Von Liebig in 1840 for growth rate of plants, stating that the size & overall health of the plant depends upon the scarcest essential nutrient available to it. Later, the concept was broadened to be applicable on all organisms. Statement: Under stable conditions,…
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Ecological Pyramids
Introduction Ecological Pyramids are graphical representation of structure & function of ecosystem at trophic levels. First described by Charles Elton, hence, also called Elton Pyramids. Show relative amounts of parameters like number, energy, biomass etc. across trophic levels. First trophic level/Producer forms the base. Successive trophic levels are represented by tiers above the base. 1)…
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Productivity, Energy Flow & Efficiency – Ecosystem
(Productivity = rate of production) There are two types of productivity: Commonly used productivity unit: Primary Productivity: Producer organisms, including both photosynthetic & chemosynthetic, convert radiant energy to organic substances and the rate at which they convert is termed primary productivity i.e. Rate of conversion of radiant energy to organic substances by producers is termed…
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Ecological Factor: Temperature
Introduction Compared to excessively wide range of temperatures existing in this universe, life is known to exist in very narrow range of temperature only. This in itself indicates that temperature has significant effect on living organisms as a limiting factor. Temperature regulates all chemical processes & many physical processes. It controls feeding, respiration, growth, reproduction,…
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Abiotic Factors
Abiotic Factors Abiotic factors are the non-living factors in our environment that affect living organisms & ecosystems. Example: Temperature, light, humidity, atmosphere, soil etc. Ecophysiology (Physiological Ecology) Ecophysiology is the part of ecology which is concerned with responses of individual organisms or species to abiotic factors. Types of Abiotic Factors we are going to study…
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Food Chain & Food Web
Food Chain Transfer of food energy from source (producer) to organisms consuming it (primary consumers) & further these organisms in turn are eaten up by organisms to which they are food source (secondary consumers) and so on, in a linear series. Types of Food Chains: Grazing Food Chain: Starts from living green plants (producers). The…
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Speciation (Formation of new species)
Definitions: Species: It is a group of organisms which can interbreed and produce fertile offspring. A species shares a common gene pool. Speciation: It is the formation of new species and diversification of species. It occurs when the common gene pool shared by a species is interrupted by isolating mechanisms. Modes of Speciation: Phyletic Transformation:…
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Major Ecosystems of the World
Overview Types of Ecosystem Artificial categorization of ecosystem can be done as following of the giant ecosystem – the Ecosphere. A) Natural Ecosystems: Self- operated under natural conditions. Natural ecosystems can be further classified as… Terrestrial- for example: Forest, Grassland, Desert, Natural Geysers etc. Aquatic- Further classified as freshwater & marine… Freshwater- Lotic (Running water):…
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Ecology: Definition, Subdivision & Scope of Ecology
The word ecology is derived from Greek language… So for an idea of Ecology, it can be said that it is study of the environmental house including all the organisms living in it & all the functional processes occurring inside it. That means we can say that ecology is basically concerned with study of relationship…