ECOSYSTEM• An ECOSYSTEM can be described simply as the collection of all living and non-living components in a particular area.• The living components of the environment are known as BIOTIC factors. Biotic factors include plants, animals, and micro-organisms.• The non-living components of the environment are known as ABIOTIC factors. Abiotic factors include things such as rocks and water.
Some Terms :• Habitat : the place where the population of organism lives.• Niche : Relational position of a species or population in an ecosystem.• Habits : something that one is used to doing; part of a routine; behavior pattern .
ECOLOGY• Derived From Greek work – oikos(home) and logos(study).• Branch of Science that deals with the interrelationship between biotic and abiotic components of nature ,as well as with the relationship among the individuals, population and community of the biotic components.
ECOLOGY DEFINED IN NUMBER OF WAYS :• According to E.P. Odum "Ecology is the study of structure and functions of nature and ecosystems“.• According to Colinvauk, "Ecology is the study of animals and plants in situations to their habits and habitats".
OBJECTIVES OF ECOLOGY• Presence of man in the ecosystem.• To understand the dynamics of our surroundings and to take proper measures to conserve it if and when required.• 1. The local and geographic distribution and abundance of organisms (habitat, niche, community, biogeography).• 2. Temporal changes in the occurrence, abundance, and activities of organisms (seasonal, annual, successional, geological).
• 3.The inter-relationship among organisms in population and communities.• 4.The structural adaptations and functional adjustments of organisms to their physical environment.• 5.The behaviour of organisms under natural conditions• 6.The biological productivity of nature and its relationship with mankind.
DIVISION OF ECOLOGYMain Divisions• Physiological Ecology (Eco-physiology) and Behavioural Ecology• Population Ecology or Autoecology• Community Ecology or Synecology• Ecosystem Ecology• Landscape EcologyAlso subdivided as Animal ecology,plant ecology,insect ecology,space ecology etc
Sustainable Development• Development that meets the needs of the present without jeopardizing the needs of the future generations.The three pillars of sustainability• Economic Development -utilization of natural resources• Social Development -basic needs like food,clothes,water,air,soil etc• Environmental Development -safe environment to present as well as future generation.
Methods to Enforce the Concept of Sustainable Development• judiciously use the resources that are available in plenty and maintain them without depletion or pollution.• restrict the use of the already endangered resources and protect them from unsustainable development.• to increase awareness about the concept of sustainable development and ensure that the people understand its full meaning.
“Ecological balance," or “Balance of nature," or “Ecosystem stability“• Balance between the production and consumption of each component in the ecosystem.To Explain the Stability of Ecosystem• Theory of Diversity or Stability• Homeostatic Mechanism• Models
LIMITING FACTORS• Limiting factors denote the amount of substance that is either least abundant or over abundant in the relation to the need of the living organism.• Density Dependent• Density Independent
LAWS OF LIMITING FACTORS• LIEBIG’s law of minimum• BLACKMAN’s law of limiting factor• SHELFORD’s law of tolerance Limit or Zone of tolerance
Every Environmental factors has 2 zones :1. Zone of tolerance2. Zone of intolerance