Climate models project that many terrestrial ecosystems will become drier over the course of this century, leading to a drastic increase in the global extent of arid soils. In order to decrease the effects of climate change on global food security, it is crucial to understand the arid environment and the constraints associated with arid soils. Although the effects of aridity on aboveground organisms have been studied extensively, our understanding of how it affects soil processes and nutrient cycling is lacking. One of the primary agricultural constraints, particularly in arid locations, is water scarcity, due to which arid soils are characterized by sparse vegetation cover, low soil organic carbon, poor soil structure, reduced soil biodiversity, and a high rate of soil erosion via wind. Increased aridity will limit the availability of essential plant nutrients and crop growth, and subsequently pose serious threats to key ecological processes and services. The increasing rate of soil salinization is another major environmental hazard that further limits the agricultural potential of arid soils. These soil constraints can be ameliorated and the crop yields increased through case-specific optimization of irrigation and drainage management, enhancing the native beneficial soil microbes, and combinations of soil amendments, conditioners, and residue management. This review explores technologies to ameliorate soil constraints and increase yields to maintain crop output in arid soils.

Conservation agriculture (CA), comprising of minimum soil disturbance and crop residue retention (>30%), with a diversified cropping system, has become increasingly popular around the world. It is recognized as a sustainable practice to improve soil health by augmenting key soil properties. However, scanty information exists about the effect of CA practices on soil organic carbon (SOC), aggregation and greenhouse gas emissions (GHG) in a vertisol. Thus, this study investigated the effect of CA practices on SOC, soil aggregation and GHG emission under soybean-wheat and maize-chickpea cropping systems in a vertisol in Central India. Treatment consisted of three different tillage practices, being conventional tillage (CT), reduced tillage (RT), and no tillage (NT) under four cropping systems viz., Soybean–Wheat, Soybean + Pigeon pea (2:1), Maize–Chickpea and Maize + Pigeon pea (1:1). Regardless of cropping system, the soil under NT and RT exhibited better aggregation (20.77 to 25.97% increase), and SOC (12.9 to 19.4% increase) compared to the CT practice in surface layers. The aggregate-associated C concentration increased with aggregate size, and it was highest with large macroaggregates and lowest with silt and clay fractions across different tillage and cropping systems. Higher SOC stock was recorded under NT (4.22 ± 0.133 Mg C/ha) compared to RT (3.84 ± 0.123 Mg C/ha) and CT (3.65 ± 0.04 Mg C/ha) practices at 0 to 5 cm depth. Thus, the adoption of CA practices reduced CO₂ emissions, while also contributing to increases in SOC as well as improvement in soil structure.