Category: Ecosystem
-
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…
-
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,…
-
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)…
-
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…
-
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…
-
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):…
-
Ecosystem Structure
On the basis of trophic structure, ecosystem is two layered: “trophe = nourishment” Autotrophic Stratum (Green Belt): Upper, self-nourishing layer of chlorophyll-containing plants. Fix the light energy, convert inorganic substances into complex organic compounds which predominate in the stratum. The most intensive autotrophic metabolism occurs in this layer where light energy is available. Heterotrophic Stratum…
-
Ecosystem (Introduction)
Introduction Ecosystem = Ecological System (Eco = Environment; System = Interacting & interdependent complex) ‘Ecosystem’ term was first used by A.G. Tansley (1935), describing a natural unit consisting of both living & non- living parts, which interact, forming a stable system. Fundamental concepts of ecosystem include… Energy flow through food chains or food webs. Nutrient…