Livelihood Augmentation in Rainfed Areas - Development Support ...

2. Ecological Variables Affecting Treatment Plan
Climate
The most important variable influencing treatment plan is climate because the total amount
of precipitation depends on it. Although climatic zones are determined on the basis of a
number of variables like rainfall, temperature and relative humidity, as a rule of thumb,
climatic conditions can be classified on the basis of average annual rainfall. Rainfed areas
in India can be classified into four broad climatic zones, shown in Table 1.
Table 1: Classification of Climate Based on Rainfall
Climate Approximate Rainfall (mm)
Arid 45 per cent), to flat
lands (0-5 per cent) and river channels. Although more detailed classifications are
available, the classification shown in Table 2 is considered practical.
Slope affects the peak rate of run-off or the rate at which the water flows over the
surface of the land. This is an equally important variable taken into account by engineers
when designing water harvesting and storage structures. In general, as we move from
Ecological Variables Affecting Treatment Plan
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