ENVIRONMENTAL SCIENCE : SOCIAL ISSUES 209
etc. Why land becomes degraded? Geological processes and anthropogenic activities are
chiefly responsible for land degradation. Can degraded land be reclaimed or rejuvenated? To
answer this grave question we have Central Arid Zone Research Area (CAZRA) at Jodhpur
concerned with the conservation of land.
During recent years increase in human activity has led to the degradation of habitat
including cultivated land forests. Mangroves etc. About 50% of the land throughout the
planet is arid with problem of acidity and salinity. Restoration of these areas is a matter
of concern for developed as well as developing countries. However, in sites method are
relatively in efficient. With the advent of biotechnology however a number of opportunities
for ‘recovery of degraded land have arisen through manipulation of biological systems.
Wasteland
Land, which does not give enough economic return or is otherwise useless, can broadly
be termed as wasteland. National Wasteland Development Board (NWDB) in the ministry
or Environment and Forest have defined wasteland as that land which is degraded and is
presently lying unutilized. Further it has classified it into two categories as i) Culturally
wasteland and ii) Non-cultural wasteland. Characteristics features of wasteland can be
summarized as under:
- The land becomes ecologically unstable and unproductive.
- Land that has nearly or completely lost its topsoil.
- Land that has developed toxicity in the zone of roots for the growth of most plants.
Land Reclamation
It is a process of making an uncultivable land fit for cultivation which is then said to
have been reclaimed. Generally it is carried out either by temporary or permanent control.
Temporary Control Includes
- Ploughing of salt-’surface crust deeply into the soil.
- Removing surface accumulation from the soil.
- Neutralizing the effects of certain salts by use of other salts or acids.
Permanent Control Includes
- Adequate lowering of water table.
- Satisfactory water infiltration.
- Leaching excess salts out of the soil.
- Intelligent management of soil.
Physical Improvements Involves
- Applying enough water.
- Keeping drains open and in good repair.
- Preventing excessive evaporation.
A few biotechnological methods are described below:.
(i) Reforestation — through micro propagation