Afforestation techniques and evaluation of different tree species for waterlogged saline soils in semiarid tropics

Abstract

Long‐term field studies were conducted on about three dozen woody perennial species to develop suitable techniques for afforestation of waterlogged saline soils in arid and semiarid regions of India. The soils of the study area were saline sandy loams with a preponderance of chloride and sulfates of Na⁺, Ca²⁺, and Mg²⁺. The soil's initial electrolytic conductivity (EC_e) was 36.4 dS m⁻¹ in the upper 30 cm. The water table was shallow, fluctuating between 1.5 m depth to the surface in different seasons of the year, and the water was brackish (average EC was 29.8 dS m⁻¹). Three methods of planting, namely, ridge‐trench, subsurface, and furrow, were compared. The furrow technique provided favorable niches for plant survival and growth and was also the most economical for such soils. Prosopis juliflora, Tamarix sp., Casuarina glauca, Acacia farnesiana, A. nilotica, A. tortilis, and Parkinsonia aculeata were found to be the most promising species for these saline soils. Casuarina glauca and Salvadora oleoides survived even prolonged stagnation of floodwaters for 9 months.

Key words:

• biomass
• bulk density
• electrolytic conductivity
• exotic species
• furrow technique
• leaching
• ridge‐trench method
• subsurface planting
• water table