Regional synthesis report - icrisat

varying degrees across villages in India and Sri Lanka. However in Thailand,
mulching (not practiced much in India), green manuring, composting, and
incorporating crop residues are popular in the upland villages, as seen in Tha Taeng
and Nong Muang villages, where over 50% of farmers practice them. These practices
are not popular with lowland farmers. The reason for incorporation of organic
sources in upland soils in Thailand is due to government interventions in terms of
imparting provision of training in organic agriculture to improve soil fertility and
water holding capacity in these villages. Adoption of improved land management is
a must for long-term sustainability; concerted efforts through different institutional
innovations should be pursued in adopting these locally proven practices
Dynamics of Sources and Availability of Water for Irrigation
Water for irrigation is the single most important factor that will neutralize the risk of
variability and uncertainty of rainfall. In the seventies, farmers across the villages in
semi-arid regions of India were dependent on tanks and open wells for irrigation.
During the nineties, selected villages (Kanzara, Shirapur, and Kinked) got
infrastructure in terms of canals and surface water for cultivation to insulate crop
production from uncertainty of rainfall. Similarly, tube wells were installed in the
nineties, and significantly increased in recent decades, thereby exploiting
groundwater. Farmers are aware that in these marginal environments, development
of irrigation sources is the key driver of change. One adverse result of this
development is that most of the open dug wells started drying up due to lowering of
the ground water table. Many of the tanks also dried up due to reduced runoff from
the catchments. Among the selected Indian villages for the study in the 1900’s; water
resources development through government interventions in the form of incentives
and investments in infrastructure took place. In Sri Lanka, most of the selected
villages are rainfed, and very less area is irrigated and a few open wells and tanks
are the sources of irrigation. Partial supplementary irrigation is practiced during the
post rainy season.
In Southeast Asia, irrigation is mainly through surface water from rivers, canals, and
ponds in lowland villages in Thailand. Besides these, groundwater sources like open
wells and tube wells cater to irrigation needs to a limited extent. The condition of
lowland villages in Thailand is similar to those in India. By contrast, in the upland
villages, very little land is irrigated and the few open wells and pond are the only
sources of irrigation. But unlike Indian villages, the development of groundwater
resources in Thailand through investment by farmers is no longer tenable as
groundwater table has gone down significantly. In Viet Nam, canal systems, wells,
and tanks are common in the villages and more than 80% of the irrigation needs are
met from the canal system and the rest from open wells and tanks. The dependence
on the canal system has increased in recent times. In China, one of the villages in
southern Guizhou (Dajiang) has met 50% of its irrigation needs from collected water
in about 500 small tanks and the rest of the area is irrigated by a pipeline system and
a reservoir built in 2009. By contrast, another village, namely Lucheba in central
Guizhou irrigates only 5% of its cultivated area through tanks and 33% is irrigated
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