STATE AGRICULTURE PLAN _SAP_ 1.0020 by keralaguest


									                                               State Agriculture Plan – Tamil Nadu    43

13. Snow covered areas
       The area covered with permanent snow cover will limit any vegetation to
come up in these areas leading to a desert like conditions. These areas are generally
associated with very high mountainous regions. The glacier regions are also included
in this category.

Degradation due to anthropogenic factors
       Human economic activities like mining, industries etc., have also contributed
to decreased biological productivity, diversity and resilience of the land. Mining,
brick kiln activities and industrial effluent affected areas are included under this type
of degradation.

14. Industrial effluent affected areas
       These are areas where the human activity is observed in the form of industry
along with other supporting establishments of maintenance. Heavy metallurgical
industry, thermal, cement, leather, petrochemical, engineering plants etc., are included
under this. These are the lands which have been deteriorated due to large scale
industrial effluent discharge. These areas are seen around urban areas and other areas
where industrial activity is prominent.

15. Mining and dump areas
       These are the areas subjected to removal of different earth material (both
surfacial and sub-surfacial) by manual and mechanized operations. Large scale
quarrying and mechanizations results in mining and mine dumps. It includes surface
rocks and stone quarries, sand and gravel pits, brick kilns, etc. Mine dumps are those
areas where waste debris is accumulated after extraction of required minerals.
Generally these lands are confined to the surroundings of the mining area.
                                              State Agriculture Plan – Tamil Nadu   44

16. Brick kiln areas

         These areas are associated with human activity and are generally seen in the
vicinity of urban activity. The areas include brick kiln per se and area dugged for
making bricks.


         Some of the degraded lands, which could not be included in the above type of
land degradation, are included here. They are mass movement/ mass wastage, barren
rocky / stony waste areas.
                                               State Agriculture Plan – Tamil Nadu       45

17. Mass movement/ Mass wastage
       Landslide areas are mostly included under mass movement/ mass wastage type
of land degradation. On sloping land when soil is saturated, the weight of the soil may
exceed the forces holding the soil in place. Under such circumstances mass movement
in the form of landslides or mudflows may occur. On steep slopes this mass
movement may be very rapid, involving the movement of large volumes of soil,
usually on an isolated event and localized basis. In geologically recent and unstable
mountain areas, such as the Himalayas, and areas prone to seismic and volcanic
activity, landslides may be natural phenomena. This class also includes the areas with
mass wastage in terms of foothill depositions like scree and bazada zones, where the
coarse material like sand and pebbles gets deposited because of erosion in upper
catchment area. However, their frequency and severity may greatly increase following
destruction of the natural vegetative cover by logging and/or clearing for cultivation
18. Barren rocky / stony areas

   Barren / rocky / stony areas are the rock exposures of varying lithology often
barren and devoid of soil and vegetal cover. They occur in hill forests as openings or
as isolated exposures on plateau and plains. These can be easily delineated from other
type of degraded land because of their severe nature of degradation and typical
spectral signature.
                                              State Agriculture Plan – Tamil Nadu   46

19. Miscellaneous

       This includes riverine sand areas, sea ingression areas mainly with sand
deposition excluding the sandy areas of desert region.

                                    Sea Ingress areas

To top