Saline and sodic soil reclamation Rajasthan, gypsum, drainage, salt-tolerant crops.
6 Answers
First get the soil tested to know whether it is saline (high EC), sodic/alkaline (high pH and ESP), or both, because the treatment differs. For sodic soil, apply gypsum based on the gypsum requirement given by the lab, mix into the top soil, then leach with good quality irrigation water and provide drainage. For saline soil, the key is leaching salts down with extra water plus proper drainage so salts do not rise again. Add organic matter like FYM, compost, or green manure (dhaincha) to improve structure. Grow salt-tolerant crops such as barley, mustard, or salt-tolerant wheat varieties in the early years. Do not apply gypsum blindly; confirm dose with your soil testing lab or KVK.
In our area near Bikaner we used gypsum with dhaincha green manuring for two seasons and the patch slowly improved. Drainage channel was the real game changer.
Check your irrigation water quality too. My borewell water itself was a bit salty, so no matter what I added the salts kept coming back until I mixed in canal water during leaching.
A word of caution from experience: do not dump extra gypsum thinking more is faster. I over-applied one year and just wasted money and money with no extra benefit. Stick to the lab gypsum requirement and re-test before the next round.
Mulching the surface after leaching helped me stop the white salt crust from coming back so quickly in the dry months. Paddy straw and crop residue kept the top layer cooler and reduced upward salt movement.
Raised beds with furrows for drainage worked for my vegetable patch on a mildly saline plot, since the roots stay in the leached zone and salts collect in the furrow. Combine it with FYM and salt-tolerant crops in the early years, and adjust everything to your soil test and local KVK advice.