Agroforestry for Rehabilitation and Sustenance of Saline Ecologies

Abstract

Saline soils constitute 15% of global landmass and have direct influence on the production functions of the existing land uses. In India, 6.75 Mha area is salt-affected, out of which 2.92 Mha are saline soils. The menace, increasing with each passing year to the irrigated areas, has become a major concern. Agroforestry plays a pivotal role in biological amelioration and check in further expansion of such landmasses. It is always useful to have agroforestry models/systems for saline landmasses by involving multipurpose nitrogen-fixing tree species, fruit trees, halophytes, and arable crops of economic importance. The potential flora suitable to saline soils has been identified based on tolerance level and climatic adaptability. The successful planting methods, viz., ridge-trench, furrow, and subsurface planting with furrow irrigation, have also been assessed and recommended for saline soils. Plant adaptations to saline conditions involve complex physiological traits, metabolic pathways, and molecular gene networks. These adaptive mechanisms to such ecologies are basically governed by one of the three processes like exclusion, excretion, and accumulation among trees and/or crops. In true sense, reclamation processes also help to keep the salt away and/or within tolerable limits for growing flora in the rhizosphere. Productive service functions of plants can be obtained from saline soils by combining reclamation and management options in pragmatic way. Sequential, agrisilviculture, agrihorticulture, silvopastoral, multipurpose wood lots, saline aquaforestry, homestead gardens, and energy plantations are the biological and economical viable recommended farm agroforestry practices in saline soils. Prosopis cineraria (Khejri) for hot dryland, Eucalyptus tereticornis (Safeda), Melia composita (Dek), Aegle marmelos (Bael), Emblica officinalis (Aonla), and Carissa carandas (Karonda) for saline-irrigated area and Casuarina equisetifolia (Casuarina), Eucalyptus camaldulensis (Safeda), and Acacia nilotica (Babul) for coastal regions as agroforestry trees in system mode are successful in reclaiming the saline soils with economic gains for sustenance. The benefits of agroforestry can be grouped into biomass, soil/environment, and socioeconomic outputs. This chapter highlights the issues in the quantification of the systems’ output in terms of existing procedural protocols. The agroforestry has passed and transcends into variable phases with the advancement as subject. Therefore, plausible future of the agroforestry is presented by taking the cognizance of present needs and future challenges in general and particular about saline soils. The holistic approaches of agroforestry undoubtedly rehabilitate saline soils and certainly will give income in perpetuity, employment generation, food and nutritional security and environmental safety for inhabiting masses in arid and semiarid regions.