Good Practices

Using water from a fishpond for the cultivation of dry season paddy rice [Lao People's Democratic Republic]

Definition of the Technology:

Technique on the use of water from fishpond for dry season rice cultivation to increase yields

Description:

This technique involves the use of water from a fishpond for the cultivation of dry season paddy rice, and it was introduced in area of 0.5 ha of irrigated paddy fields in 2010. Dry season rice cultivation is normally prevented by an inadequate water supply. Farmers can usually only practice rain fed rice cultivation. However, in 2012 one land user had an idea so as to maximize the use of his land. He hired a backhoe in order to excavate a pond which he could then use for fish breeding. The pond’s total volume is 1,700 m2 and it measures 50 meters x 30 meters, with a depth of 1.5 meters. A canal had been dug to fill the pond with water from a nearby stream. The pond is utilized for fish breeding, and the water is also diverted for the cultivation of rice in both the dry and wet seasons. This is done by utilizing small 40 cm wide irrigation canals which were established to supply water to the rice paddies. This technique therefore not only assists agricultural practices but also enables aquaculture and thus has provided households with increased food security. Furthermore the rice paddies have become more productive throughout the plantation periods. The fishpond also manages to control erosion as it retains the run-off water from the surrounding forest areas. This run off is held by the pond before it reaches the rice fields. Therefore, the technique helps to sustain agricultural activities on the land and reduce localized drought. However, supplying water to areas that are at a higher elevation than the pond remains difficult; farmers are unable provide sufficient amounts of water without the use of a pump. After adopting this technique land users have been very satisfied with the outputs as they can cultivate rice throughout the year, so in both the dry and the rainy seasons, and as a result have produced higher yields of rice. They have also been able to raise fish which has provided meat for household consumption. This means that the families applying the technique are currently better off. Additionally, the soil has become moister and this has prevented the development of clods as had happened in the past. The fishpond is 50 meters long, 30 meters wide and has a depth of 1.5 meters. The water gate, which measures 40cm x 40cm has been constructed with planks. In the dry season particularly when there is an inadequate amount of water in the rice field, the farmer will open this gate so as to divert water from the pond to the rice fields. They are able to use half of the pond’s volume of water at one time, and then it will gradually have to be filled up again with water that runs through a canal from the stream. It takes a few days to refill the pond and then the farmers are once again able to irrigate their paddies. The pond was established right next the rice paddies which can be fed through a 40 cm wide canal that is blocked by a wooden gate when not in use. Additionally a 5 HP, diesel water pump is used to pump water uphill from the fishpond to another 0.5ha paddy field. This is necessary because the paddy field, on a slope of 3-5% is located at a higher elevation - which is a characteristic feature of rice paddies. The species of fish fingerlings in the pond include tilapia, common carp and grass carp. As the fish are maturing the land users mostly feed them with rice bran because it is readily available. A plastic net is used as a filter in front of either the pump inlet when irrigating the paddy field upstream or the gate when water is being diverted to the paddy field downstream so as to avoid the loss of fish. The pond has a storage capacity is 2,000 m3 and it is replenished from a natural source by a canal that was recently constructed by the land users. Strengths: (1) Water from the fishpond can be used for rice cultivation in both the dry and rainy seasons, thereby enabling agricultural activities without the provision of water from an irrigation system. (2) It enables fish breeding and therefore land users can propagate various fish fingerlings. Weaknesses: (1) The fishpond is located at a lower elevation than some of the paddy fields and thus only a limited area can be supplied through gravity fed irrigation ; (3) A diesel water pump is needed to supply water to some of the fields to enable the cultivation of rice.

Country:

Lao People's Democratic Republic

Region/ State/ Province: TaOuy District, Salavan Province

Further specification of location: Doup village

For mor detials

Source: LaoCAT, NAFRI, MAF

Author: LaoCAT, WOCAT