Environmental concerns

1. Depletion of water resources
Tamil Nadu's geographic area consists of 17 river basins, a majority of which are water-stressed. There are 61 major reservoirs; about 40,000 tanks and about 3 million wells, that heavily utilize the available surface water (17.5 BCM) and groundwater (15.3 BCM). Agriculture is the single largest consumer of water in the State, using 75% of the State's water. A recent World Bank report has shown that the agriculture sector faces major constraints due to dilapidated irrigation infrastructure coupled with water scarcity due largely to growing demands from industry and domestic users and intensifying interstate competition for surface water resources. In some parts of the state, the rate of extraction of groundwater has exceeded recharge rates, resulting in falling water tables. Water quality is also a growing concern. Effluents discharged from tanneries and textile industries and heavy use of pesticides and fertilizers have had a major impact on surface water quality, soils and groundwater. The State Government has taken a number of progressive actions on water resources and irrigation management, particularly through the Bank-assisted Tamil Nadu Water Resources Consolidation Project (WRCP). Tamil Nadu was one of the first states to pass a groundwater bill, Procurement/Right to transparency act and a farmers management of irrigation systems act. The State has prepared a planning framework for water resources management, and a State Water Policy.

2. Smaller size of holdings
Land holdings- Constantly rising demography pressure on land is a serious cause for concern. The marginal and small farm holdings accounts for 89% of the total holdings and the area operated by them 52% of the total area. The per capita availability of land has been continuously declining and the availability of cultivable land is even worse. Land is not only an important factor of production, but also the basic means of subsistence for majority of the people in the State of Tamil Nadu.

Together with the shrinking area under cultivation, the pattern of land ownership is also unfavourable for agricultural development. The average size of holdings has declined from 1.25 ha in 1976-77 to 0.95 ha in 1995-96. The all India figure for average area owned per household is 1.59 ha. This reflects the pressure of population on land. The share of total land operated by small and marginal farmers has increased from 42 percent to 52 percent during the same period. The growth in number and extent of small and marginal farmers is a major hurdle in promoting capital investment in agricultural sector and modernizing agriculture sector. Fragmentation of land results in uneconomic land holdings.

3. Land degradation and soil quality
Land is an important natural resource for agriculture. Land degradation adversely affects agricultural production. Crop yields are dependent on certain soil characteristics- soil nutrient content, water-holding capacity, organic matter content, acidity, top soil depth and soil biomass and so on.

4. Soil erosion
Soil erosion is by wind or water. Erosion causes depletion of fertility through the removal of the valuable and fertile surface soil. In Tamil Nadu erosion is observed in and around 13 lakh ha.

5. Salinity and alkalinity
The adverse effect of salinity in soil is that it hinders crop growth and results in reduction in crop yield. The estimated extent of soils affected by salinity and alkalinity is estimated at 2.48 L.ha. besides 1.23 L.ha. suffering from acidic soils.

6. Water logging and marshy land
Excess water hinders plant growth by reducing aeration, which in turn decreases the water absorption and nutrient uptake by roots. The coastal regions of Tamil Nadu face heavy damages due to water logging. The command areas in major irrigation projects experience water logging problem. In Tamil Nadu 44,820 ha. is estimated as marshy lands. About 14 percent of the area in Tamil Nadu is under very poorly drained soils. Another 16 percent is under moderately well drained to well drained soils and 15 percent is somewhat excessively drained soil.

7. Decline in soil organic matter
The soil health is deteriorating. The organic matter content in the soil has gone down from 1.20% in 1971 to 0.68% in 2002 in Tamil Nadu, because of less use of organic inputs.

8. Gullied/ Ravine lands
The gullies are the first stage of excessive land dissection followed by their networking which lead to the development of ravine land. The ravines are extensive system of gullies developed along nullas, streams and river coarse. It has been estimated that Tamil Nadu has 22,550 ha. under gullied / ravine lands. Wastelands are degraded lands that can be brought under vegetative cover.

9. Tannery and Textile Industrial Pollution
The study carried out by the Loss of Ecology Authority, Government of India, revealed that the tannery industries have adversely affected 15,164 ha. of agricultural land in Vellore district and 2,005 ha. in Dindigul district. The Authority had looked into the problem of pollution caused by the tanneries located in Vellore, Dindigul, Kancheepuram, Thiruvallur, Erode and Tiruchy districts and awarded a total compensation of Rs 34.73 crore. This amount, to be recovered from the tanneries, will be used for paying compensation to 36,056 individuals, besides helping in reversing the ecological damage caused by these tannery industries4. Tirupur is a fast growing hosiery 'Industrial City' in Coimbatore district of TamilNadu. It is located on the bank of the Noyyal river. The effluent discharged by the textile industries released into the Noyyal river pollutes the surface and ground water and damages the agricultural land. An environmental damage assessment study carried out by Madras School of Economics on agricultural lands showed that the total irrigated area declined from 16,262 ha. to 14,262 ha. On the other hand rain fed / non-irrigated land increased from 2108.3 ha. to 2668 ha. The study also showed that irrigated crops like paddy have completely disappeared, resulting in an output loss of Rs. 8.62 lakh in 1994-95 harvest prices. The gross output loss for all crops in the 4 villages studied is Rs. 25.23 lakhs.

10. Mining and Environmental degradation
It has been estimated that 16250 ha are under mining in Tamil Nadu of which 3285 ha are in the district of Salem followed by 3155 ha in Cuddalore district. The other districts which have fairly substantial area under this category include Namakkal, Perambalur, Tirunelveli and Sivagangai. Sand quarrying results in loss of soil, renders waste farmland, devastates agricultural activities and livelihoods, depletes and salinates groundwater quality and changes river courses.

11. Constraints
Marginalization of land holding, high variability in rainfall distribution, inadequate capital formation by the public sector, declining public investment on agriculture, declining net area sown, over - exploitation of ground water and inadequate storage and post harvest facilities affect the agricultural performance in the state. The state supports seven percent of the country's population but it has only four per cent of the land area and three percent water resources of the country. Of the total gross cropped area, only 50 percent of the area is irrigated in Tamil Nadu. Similarly, of the total area under food grains, only 60 percent of the area is irrigated. Nearly, 52 percent of area is under dry farming conditions in Tamil Nadu apart from stable cropping intensity which is hovering around 120 percent over the period. In spite of the above constraints, the State has made tremendous performance in the production of crops, which is attributed mainly to the productivity increase.