Resilience of the Semi-Arid Tropical Soils

Abstract

Soils in the semi-arid tropics (SAT) are subject to chemical degradation mostly due to climatic reasons which make the pedo-environment hostile to form calcium carbonate. This triggers an overall deterioration of soil properties affecting its physical and chemical parameters. Such soils require management interventions which may include chemical and other phytoremediation process. The present paper details this process of degradation in light of resilience of these soils of SAT.

ICRISAT, India Soils:Yesterday, Today and Tomorrow

“…We made an effort to understand the nature of the SAT soils as it would exist in years to come. Judging by the rate of changes in chemical and physical soil parameters (Table 9) and also on the basis of available trend of data in the semi-arid tropics 27,35,[37][38][39] , we attempted to project changes in soil properties in case the present land use and management interventions are continued (business as usual, BAU) and also, if appropriate, management interventions are adopted 40 ( Figure 10). It is quite likely that soil organic C level in black soils will further decrease until management interventions are CURRENT SCIENCE, VOL.…”

“…However, the values shown under interventions in these figures emanate from the experience gathered in red and black soil research over the years 19,20,23,26,40 . Our observations suggest a progressive development of subsoil sodicity due to increase in pedogenic carbonates (PCs) under SAT environment with time when anthropogenic activities in terms of sustainable management interventions to raise agricultural crops are not made ( Figure 12).…”

Comparison of methods for evaluating the suitability of Vertisols forGossypium hirsutum(Bt cotton) in two contrasting agro-ecological regions

“…Thus, CaCO 3 does not constrain growth in Dhar soils, whereas in Thimmajipet soils, higher free CaCO 3 content in the surface horizon modifies soil properties to make them chemically degraded (Bhattacharyya et al 2016). Mean organic carbon was lower (0.26 %) in Dhar than the Thimmajipet (0.48 %).…”

“…Thimmajipet soils, occurring in SAD region with high ESP (13.7-46.6) and calcareousness are very hard when dry, adversely affecting crop growth. Optimizing the physical and chemical properties of the Thimmajipet soils to make them suitable for cotton cultivation would require (expensive) chemical amelioration measures (Pal et al 2000;Bhattacharyya et al 2016). The indicators selected for assessing SQI depend on both the requirements of particular crops, and the available data (Qi et al 2009).…”

“…For example, reduction in mean annual rainfall (MAR) can lead to the formation of calcareous and alkaline soils with elevated pH and calcium carbonate contents (Pal et al 2012). However, Bhattacharyya et al (2016) found that the chemically degraded Vertisols can be highly receptive to management interventions, such as amelioration with gypsum and irrigation with good quality water. In the SAT regions, Vertisols vary from Typic Haplusterts in humid tropical, Typic/Udic Haplusterts in semi-arid moist, and sub-humid dry climates and Sodic Haplusterts and Sodic Calciusterts in semi-arid dry (SAD) and arid dry climates (Pal et al 2009).…”