Costing and Estimation ofWorks - Afforestation, Reforestation and Forest Restoration in Arid and Semi-arid Tropics - page 186

water conservation works, yet where the plantation area is large, has undulating
or sloping terrain, and the expected runoff is significant, such measures should be
incorporated to save on cost of artificial watering. In case of tree groves in houses
and institutional premises, the domestic sewage effluent—from drains, soak pits, or
baths—can be used to irrigate plants. Table 7.12 lays down a model treatment for
UAP-400.

7.2.7 Regenerative Closures (RC)

This model aims at restoration of existing forests without resorting to artificial plant-
ing. It is meant for degraded areas having semi-arid or sub-humid conditions and
where the density of rootstock is high. Fencing the area, treating the existing root-
stock, executing soil and water conservation works, and sowing seeds of tree and
shrub species are the major items of work in this model. Total cost per hectare is much
less compared to other models and the impact is often more spectacular. The period
of intensive management is assumed 5 years and the period of eventual protection
for complete restoration and ecological rehabilitation could be 10 years. Table 7.13
lays down the treatment plan for RC.

7.2.8 Abstract of Afforestation Costs

Table 7.14 summarises total costs over the period of 5 years for the different models,
and also indicates the break-up of cost by the major items of work. The last column
in this table indicates the cost per plant, which is a measure of cost effectiveness of
the model, though planting nursery-raised seedlings need not be the option of choice
in all afforestation programmes.

7.3 Units of Measurement and Conversion Tables

Use of units and their interconversion is important in estimation work as well in
record-keeping and accounting. Use of SI (metric) units is almost universal, yet
local preferences may sometimes dominate. Field workers may not be conversant
with the metric units, and may find it difficult to comprehend anything other than
what they are used to in daily life. This topic uses metric units throughout—in all
tables and charts, and in all descriptions of specifications of work items. Therefore,
it is desirable to provide a comprehensive guide to converting metric units into other
systems of measurement.
Commonly used length measures are feet and metre and their associated sub-units.
These have been listed in Table 7.15 and their equivalent values in terms of metre
have been indicated. To express a length in terms of metre, one just has to multiply
the given quantity in other units by the value shown in last column of the table.