OUR ENVIRONMENT

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MANAGEMENT OF NATURAL RESOUCES

Maha.

i) Biodegradable wastes :- are wastes which are decomposed into harmless substances by microorganisms. Eg :- vegetables, fruits, pulses, cereals, cotton, jute, wool, wood, leather, paper, animal dung, animal bones etc.ii) Non biodegradable wastes :- are wastes which are not decomposed by microorganisms. Eg :- polythene bags, plastics, synthetic fibres, glass, metals, synthetic rubber, insecticides, pesticides etc.

Ecosystem :- An ecosystem consists of all the living organisms in an area along with the non living components and their interaction. There are different types of ecosystems. They are :- i) Natural ecosystems :- like forests, deserts, grass lands, mountains, ponds, lakes, rivers, oceans etc. ii) Artificial ecosystems :- like gardens, parks, crop fields, aquarium, zoo etc.

Components of an ecosystem :- An ecosystem consists of two main components. They are biotic and abiotic components. i) Biotic components :- are the living components like plants, animals and microorganisms. They consist of producers, consumers and decomposers. Producers :- are green plants which produce food by photosynthesis. Consumers :- are herbivores which get their food directly from plants, carnivores which get their food indirectly from plants and omnivores which get their food directly or indirectly from plants. Decomposers :- are microorganisms which decompose dead plants and animals. They decompose complex organic substances into simple inorganic substances in the soil which are again used by plants.ii) Abiotic components :- are the non living components like air, water, soil, minerals, sunlight , temperature, wind etc.

FOOD CHAIN:-

A food chain is the flow of food energy from one organism to the next and to the next and so on. They usually start with a producer (plants) and end with a carnivore. In a food chain an organism gets food from one group of organisms.

FOOD WEB:-Food web is a group of several interconnected food chains. In a food web an organism gets food from more than one group of organisms.

Human activities affect the environment :-

Depletion of ozone layer in the atmosphereManaging garbage we produceSeawage treatment

Land fills Recycling

Production of biogas and manure Preparation of compost

Sewage treatment

Natural resources:- Natural resources are the resources available in a nature like air, water, sunlight, soil, minerals, forests, wild life etc. Natural resources are of two main types. They are renewable and non renewable natural resources. i) Renewable natural resources :- Are the resources which can be replenished in a short period of time like air, water, sunlight, forests etc. ii) Non renewable natural resources :- Are the resources which cannot be replenished in a short period of time like minerals (coal, petroleum, natural gas, metals etc.) because they take millions of years to be formed. Human activities produce a lot of waste materials which are thrown away into the environment. These wastes cause pollution of natural resources like air, water and soil.

NATURAL RESOURCES

The Three R’s to save the environment

WE ARE GOING TO KNOW ABOUT:NEED FOR MANAGEMENTING NATURAL RESOURCESIMPORTANCE OF FORESTS CONSERVATION OF FORESTSUSES OF WATERADVATAGES &DISADVANTAGES OF DAMSIMPORTANCE OF WILDLIFECONSERVATION OF WILDLIFECOAL AND PETROLEUMACID RAIN FORMATION