Geo-environmental feedback of present climate change in the Rajasthan state, north-west India

Abstract

The Thar Desert is a part of the arid zone of north-western India and one of the major deserts in the subtropical belt, encompassing a total geographical area of 196 000 km2. Ongoing desertification with intense erosional actions removing unconsolidated surface cover to form desert pavement on one side, and co-acting mass sediment transfer with sand dunes formations on another side, as well as ground salinisation due to progressing regional aridification (mean annual precipitation 150–500 mm) pose major threats to the local ecosystems and occupation habitats. A broad annual temperature range (5–50ºC) contributes to intensive physical and chemical weathering and, in the absence of compact vegetation cover with increased windiness, to a large-scale sediment transfer. These negative effects are responded to by new agricultural strategies contributing to the socio-economic sustainability of the western Rajasthan. The major strategic geo-environmentally-based aim is implementation of modern approaches and innovative techniques enhancing productivity of the Thar area farmlands in view to the steadily rising local demography. Innovative, effective and relatively low-cost approaches and new technologies are being applied aimed at establishment of countryside-protective plantations, wind erosion control, active sand dune stabilisation through tree plantation, artificial watershed and water retention reservoir establishment, wasteland mitigation, desert land farming systems and some other alternate land use strategies reflecting the regional natural conditions and socio-economic needs. Yet, the intensified agricultural land use with a locally excessive artificial irrigation from artesian wells together with livestock overgrazing of the sparse vegetation generate an increasing anthropogenic pressure to the fragile (semi-)desert ecosystems. This is balanced by natural remediation though the innovative crop cultivation and predominant traditional nomadic pastoralism. The current integrated geo-and bioscience research focus is on the effects of the present climate change to both the pristine and anthropogenically used (occupied) lands, 73% of which is directly exposed to wind erosion and certain (arable land) degradation, the modern relief formation as well as the present human influence to the environment. Knowledge of the acting climate variations affecting the landscape (relief and biotic) diversity and pre-determining the actual economic potential in the Thar Desert area is therefore essential in terms of documenting the most recent regional geological history and geomorphic transformations in addition to the environmental adaptations of people in the frame of sustainable development of this NW India’s most arid zone. New wind-exposed archaeological sites add to the existing cultural heritage of the country. © SGEM2018.