In dryland, irrigation is essential for agricultural production. However, salinization induced by irrigation and insufficient leaching is a serious problem in arid to semiarid regions. Indo-Gangetic plains (IGP) located in North part of India is currently suffering from serious salinization. The salt affected soil area extends to approximately 6.7 million ha. Of these, 3.78 million hectares are sodic soils. Development of sodicity and subsurface sodicity even in reclaimed soils of these semi-arid tropics is a chemical degradation process. When salt gets accumulated in the soil, a huge manpower and funds are required to reclaim such salt affected farmland. Therefore, as the first and important step of measures against salinization is the prevention of salt accumulation. The main causes of salt accumulation due to irrigation agriculture are use of high salinity water, excessive irrigation, and poor drainage. Therefore, applying technologies which save irrigation water and improve drainage function can be effective in preventing salinization. However, these technologies such as drip, sprinkler, sub-surface drainage require a lot of funds and maintenance cost. Considering this situation, in order to realize sustainable agriculture, it is necessary to establish low-cost water management technologies which farmers can practice with ease. Therefore, we decided to focus on utilizing tractor mounted machine for improving drainage function and modifying furrow irrigation to reduce the cost of measures.
Japan International Research Center for Agricultural Sciences (JIRCAS) and ICARCentral Soil Salinity Research Institute (CSSRI) India are working in collaboration to develop low-cost techniques for the management of saline soils of India for sustainable agricultural production from 2018. The “Cut-soiler” a tractor mounted machine that constructs residue filled preferential shallow sub surface drainage was introduced to India under this collaborative project. In addition, as water-saving technologies, Permanent Skip Furrow Irrigation (PSFI) and Simplified Surge Flow Irrigation (SSF) were introduced and being evaluated.
In this User’s Guide, explains how to apply these technologies and shows their effectiveness on salt-affected farmland.