Glossary - Afforestation, Reforestation and Forest Restoration in Arid and Semi-arid Tropics - page 278

Underground water reservoir Water reservoir constructed by excavating a large
pit, usually of cubic or cylindrical shape, and lining it with brick or masonry and
plastering over it to make it impervious. Since the water pressure is retained by earth
on sides, a UGWR can be far more economical in terms of capital cost than an OHR
or a GLR.

User groups Groups of people making a specific use of, or deriving a specific
advantage out of, a common property resource.

VA M ⇒ Vesicular arbuscular mycorrhizae.

Vandalism Wilful or malicious destruction of public property.

Vesicular arbuscular mycorrhizae Root associative fungi with a broad host range.
These fungi have an important role to play in forestry. The fungi feed on carbohydrates
produced by the plant and in turn improve uptake of phosphorus and other nutrients by
the plant roots. The total surface area of the roots is increased manifold which makes
the roots more effective in their function. Most terrestrial plants are mycorrhizal,
though their dependence on fungi for uptake of phosphorus varies. The group of
fungi known as VAM are specially important in case of plants growing in poor and
infertile soils. They increase tolerance of plants to adverse factors such as high soil
temperature, moisture stress, root diseases, and parasites. In arid areas, they improve
soil structure and assist the nitrogen-fixing organisms in case of leguminous plants.
While using VAM inoculum in nursery or in field, it must be noted that though they
are not host specific, they do show species preference.

Vegetative barriers Linear barriers, especially running on contours, consisting of
live hedge of shrubs meant to prevent soil erosion.

Vegetative propagation Propagation by non-sexual processes, such as by cuttings

or tissue culture.

Vermiculture A method of decomposing organic waste by inducing culture of
worms.

Viability of seeds ⇒ Seed viability

Village woodlot A woodlot reserved for meeting the fuelwood and other petty needs
of the people in a village.

Walkthrough Inspection of a tract of land or a plantation by randomly walking
across it in transects or along a regular pattern.

Wasteland Barren or uncultivated land not producing anything or producing far
below its optimal level.

Water table The upper limit of the portion of the ground wholly saturated with
water. Most of the arid and semi-arid regions are characterised by a low water table,
making it more expensive in terms of energy to draw water. Degradation of forests
and vegetation in the watershed leads to lowering of water table and consequent ills
associated with it.