Use of Remote Sensing in Environmental Protection

Remote Sensing refers to any method, which can be used to gather information about an object without actually coming in contact with it. Any force field like acoustic, gravity, magnetic, electromagnetic, etc., could be used for remote sensing, covering various disciplines extending from laboratory testing to astronomy. At present the term "remote sensing" is used more commonly to denote identification of earth feature by detecting the characteristics electromagnetic radiation that is reflected/emitted by the earth.

Remote Sensing System for Resource management

Remote Sensing data ( Image) have been used to derive thematic information on various natural resources and environment. This type and level of information Extracted depends on the expertise of the analyst and what he is looking in the data.

Examples -

The remote image of the land can be used to derive information of vegetative cover, water bodies, land use, pattern, geological Features, soil etc.,

Applications Of Remote Sensing :

1. In Agriculture :

In India, the agriculture sector sustains the livelihood of around 70% of the population and contributes to about 35% of the net national product. We require judicious and optimal management of both land and water resources along with the use of high yielding variety seeds, optimal fertilizer input, post central etc., Remote sensing can provide valuable information for the land and water management.

2. In Forestry :

Sustainable forest management requires reliable information on the type, density and extent of forest cover, wood volume and bio mass, forest fire, pest and disease induced losses., encroachment etc., Remote sensing provides all such information clearly.

3. In land cover :

Spatial information on land use is required at different scales depending upon use. Remote sensing data is converted to map, the spatial resolution plays a role on the scale of mapping.

4. Water Resources :

Remote Sensing data has been used in many applications related to water resources such as surface water body mapping, ground water targeting, wetland, inventory, flood monitoring, reservoir sedimentation, water quality monitoring, run-off modelling, snow cover monitoring, Irrigation water management and many more. One of the most simple applications is inventorying in surface water bodies.

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