Agriculture Reference
In-Depth Information
FIGURE 1
Proportion of area under different micro irrigation systems in India and Tamil
Nadu.
The area under micro irrigation is very low in Tamil Nadu compared to the na-
tional level area. The net sown area in Tamil Nadu is 5,126,000 ha, whereas the gross
cropped area is 5,842,000 ha. The area under micro irrigation accounts for only 3.1%
of the net sown area in Tamil Nadu, whereas it accounts for 5.49% of the net irrigated
area and 4.79% of the gross irrigated area. Thus, there is a huge potential to increase
the area under micro irrigation in Tamil Nadu.
2.3.2 COIMBATORE DISTRICT OF TAMIL NADU STATE
The study area included the Coimbatore district of Tamil Nadu state, where the agri-
culture depends largely on minor irrigation projects and other sources such as wells,
rain-fed tanks, etc. The chief source of irrigation in this district is through wells. The
average well-failure rate is 47% for open-wells and 9% for bore-wells [14]. There are
six different soil types viz.: red calcareous soil, black soil, red noncalcareous soil, al-
luvial and colluvial soil, brown soil and forest soil. The mean annual rainfall for the
45 years (between 1961 and 2005) is 687.1 mm and the with a coefficient of varia-
tion of 28.21%. The distribution of rainfall across the seasons indicates that the mean
rainfall ranged from 16 mm during winter to 348 mm during north-east monsoons.
The groundwater potential as on January 2003 indicated that the total groundwater
recharge was 880.97 million cubic meter (MCM), net groundwater availability (90%
of total groundwater recharge) was 792.87 MCM, domestic and industrial draft was
40.57 MCM, irrigation draft was 779.13 MCM and the stage of groundwater develop-
ment was 103%.
The level of groundwater development exceeds 100% of the utilizable ground-
water recharge in 11 blocks, between 90 and 100% in four blocks and between 70
and 90% in another four blocks. The stages of groundwater development in the study
blocks was 169% for Thondamuthur block and 173% for Annur block, respectively.
This indicates the problem of groundwater in the region. Increasing private investment
on wells is visualized over the years, as groundwater irrigation assumes importance.
Farmers in this district rely heavily on groundwater for irrigation. The source-wise
area irrigated indicates that the groundwater accounts for 88.7% and 52% of the total
area irrigated in the Thondamuthur and Annur blocks, respectively. The increasing
trend in groundwater irrigation further confi rms a heavy dependence on it for irriga-
tion.
Search WWH ::
Custom Search