Climate smart water saving techniques for mitigation of climate change impacts in hill agriculture
Contd from prev issue
Water can be conserved in a number of ways by using it more efficiently than most conventional practices.
1. Water saving techniques for rice
Rice is an important cereal crop grown in the northeast region. Different water saving techniques for rice cultivation are in practice in many parts of the region. Achieving higher water use efficiency by using less water to obtain higher rice yield is very important in the context of climate change. Different water saving techniques are briefly explained here.
A) Alternative wetting and drying (AWD)
In this technique the irrigation water is applied to flood the field for a certain number of days after the disappearance of ponded water. Thus, the field is alternately wetted and dried for the certain period. Research studies have reported enormous potential for saving water and increased productivity of rice grown using this method as compared with traditional flooded rice cultivation. In this method water saving up to 15-30% can be achieved compared to conventional methods of rice transplanting.
B) System of rice Intensification (SRI)
In this method the fields are kept un-flooded and the soil well aerated throughout the entire vegetative growth. Only a little water is kept on the field during the reproductive growth phase. This method is becoming popular among the smallholder farmers of hill regions. Using SRI methods of farming, farmers can get higher yields with fewer inputs.
C) Aerobic rice
In these techniques the rice is cultivated like wheat and maize crop as irrigated upland crop. Irrigation is applied to bring the soil water content in the root zone up to field capacity after it has reached a certain lower threshold.
D) Saturated soil culture (SSC)
The soil is kept as close to saturation as possible. Studies have shown that using this technique, water input decreases by 5% to 50% from the continuously flooded check basins with an average of 23%. This method has reported the reduction in yield about 6% on an average but the overall water productivity increases.
2) Drought tolerant crops and seeds
This is in principle of growing the right crop for regions which suffer from water shortages. Therefore, it is necessary to grow such crops which are more tolerant to drought. These include finger millet, pearl millet, guinea millet, cowpea, and sorghums.
3) Conservation agriculture
In conservation agriculture, reduce tillage and mulch cover results in less surface runoff and higher water infiltration than is the case with conventional tillage. In addition, the basins, furrows and rip lines collect runoff and this water becomes available to the crops. Mulching further in moisture conservation by shading the soil surface and reduces evaporation.
4) Water management through
a) Irrigation scheduling:
Irrigation scheduling implies when to apply and how much to apply. Well planned irrigation schedule is useful to reduce the water losses and increase the crop yield. Use of soil moisture sensors in irrigation systems is an important tool for water conservation. It not only prevents over-watering, but saves unnecessary pumping costs and helps prevent leaching of fertilizers.
To be contd