POLLUTION
sanaPollution has been defined by Odum (1971) as "the undesirable change in the physical, chemical or biological characteristics of air, land and water that may affect the human life. The…
SALINITY
The soil in which salt crust is left due to evaporation of water is called saline soil and this problem is called salinity. A saline soil has electrical conductivity of…
WATER LOGGING
The soil which is saturated with water is called water logged soil and this problem is called water logging. Causes of water Logging Pakistan has one of the best canal…
Conservation
The management of the earth resources to restore and maintain balance between human requirement and other species in the world is called conservation. Conservation includes continuous renewing of renewable resources.…
BIODIVERSITY
The variety of living organisms in an ecosystem is called biodiversity. The exact number of species in the world is not known. The taxonomists have described about 1.4 million species.…
ARIDITY
The word arid means dry. The dry land is called arid land. This problem is called aridity. Arid climate is defined as the climate in which precipitation is less than…
OBJECTIVE FOR ECOSYSTEM
Multiple Choice Questions (MCQs) The maximum percentage of energy changed into food is: (a) 10% (b) 20 (c) 30 (d) 5 Percentage of energy absorbed in atmosphere is: (a) 50 …
SUBJECTIVE AND SHORT QUESTIONS FOR ECOSYSTEM
MODEL SUBJECTIVE QUESTIONS: What is ecosystem? Give its components. Give physiognomic characteristics. Write note on ecological energetics. Write note food chain, food web and trophic levels. Write note on ecological…
DEFINITIONS AND KEY POINTS FOR ECOSYSTEM
TERMS DEFINITIONS Ecosystem A community with its non-living environment is called ecosystem. Decomposers The microorganisms which decompose the bodies of dead animals and plants are called decomposes. Ecological energetic The…
HYDROLOGICAL CYCLE
Water is essential for all the life processes. About 80% of water is present in a living cell.- It covers about 73% of surface of the earth in the form…