Agriculture Reference
In-Depth Information
Many times watershed approach is followed in formulating afforestation pro-
grammes, or afforestation may be one of the components of a larger watershed
development programme. Although such integrated watershed development pro-
grammes envisage a comprehensive and holistic treatment of land within the
watershed (e.g. the ridge-to-valley approach), yet it will not be feasible to treat
the entire land marked for afforestation works at one go. Fencing all the commons
land might not be feasible if no alternative grazing lands are available. Sometimes
commons land may be encroached upon by individuals and access for afforestation
may be denied. In such cases, sites should be selected on the basis of prioritisation
in terms of land availability, site quality, and the need to rehabilitate a particular area
with a view to preventing further ecological degradation.
An afforestation programme may have a built-in formal procedure for identifica-
tion of sites on the basis of micro-plans covering individual territories or forest blocks.
In such a case, selection of site is done in accordance with the principles laid down
in such micro-plans which will often require participatory rural appraisal exercises.
3.2
Surveying a Site Using Chain and Compass
Once a plantation site has been selected, it needs to be surveyed, its area determined,
and its relief and other features put on a map. Surveying can be carried out using one
of the various methods, each distinguished by use of particular equipment. Choice
of the method is determined by considerations such as need of accuracy, terrain
relief, availability of skilled manpower, details to be brought out in the subsequent
treatment plan, and time and cost at hand. In all cases, the purpose of the survey is
to determine the shape, the area, and the relative position of the relief features, so as
to arrive at quantitative and qualitative decisions involved in preparing the treatment
plan (Fig. 3.1 ).
Chain-and-compass survey is a simple method and is suitable for most afforesta-
tion works, except for the sites that demand very high level of accuracy and detailed
delineation of the relief features of the land (e.g. where a number of engineering
structures are involved). It has the advantages of being simple, direct, fast, and
cost-effective.
The equipment used consists of a chain, a prismatic compass, and a set of ranging
rods. If the terrain is flat and free from shrubs and other obstacles, a steel tape can
be used, instead of a chain, for ease and speed in handling. The prismatic compass
should have a precision of half a degree. The ranging rods (used in aligning and
sighting of stations) can be made of local materials like bamboo or old disused pipes
painted in sections of white and red.
After carefully traversing the area on foot, the corners (or sighting stations) should
be identified and marked with pegs having red flags. Consideration should also be
given to the fact whether the kind of fencing required will be feasible through the
stations being selected. For instance, if the traverse points fall on too steep a slope,
stone wall, or ditch fence will not be feasible, and hence the line of sight must be
shifted to pass over terrain where fencing will be easier to execute.
Search WWH ::




Custom Search