Use of Highly Saline Water Beyond Common Agricultural Crops

Under situations when economic production of agricultural crops is not feasible due to high salinity of irrigation, a better land use option is to grow very salt tolerant species such as halophytic trees, grasses and other species with their produce having high economic value. In addition to fuel, fodder and timber production, tree plantations also provide ecological and environmental advantages. With advances in the understanding of managing plantation forestry, it has now emerged that subject to the following of innovative techniques and selection of appropriate tree species, i.e. tolerant but fast-growing, plantation forestry programs can be successfully implemented with saline irrigation on marginal lands. Sub-surface planting and irrigation through furrows create better salt regimes such that satisfactory establishment of trees was possible with only 10–15% of the irrigation applied in raising crops for about 2–3 years. Several plantation species including Acacia modesta, A. nilotica, Azadirachta indica, Eucalyptus camaldulensis, E. occidentalis, E. spathulata, E. tereticornis, Prosopis cineraria, P. Juliflora and Tamarix articulata perform consistently well when irrigated with high saline waters. Grasses such as Distichlis spicata, Echinochloa crusgalli, Leptochloa fusca, Paspalum vaginatum, Sporobolus arabicus and Sporobolus virginicus were more productive. Typical advantages of irrigating forage grasses with saline irrigation included: high levels of forage productivity, about three- to fourfold increase as compared with natural/seeded rainfed pastures and the opportunities for out-of-season forage supplies. Several other halophytes such as Atriplex hortensis, Chenopodium quinoa, Citrullus colocynthis and Salicornia bigelovii are now projected as alternatives to the prevalent crops in saline water-irrigated areas.