Long Term Monitoring of Ecological Status of Major Deserts of the World

Abstract

Deserts are unique ecosystems that provides suitable habitats to many floral and faunal species and that are beneficial to human beings in many ways. Desert ecosystems are affected by several natural and anthropogenic factors, resulting in the degradation of ecosystem goods and services provided by them. Thus, there is a need to monitor them. Accordingly, the ecological status of 34 major non-polar deserts of the world have been monitored for a period of four decades. We have used (i) vegetation cover and NDVI (vegetation density/vigour) as indicators of ecological conditions, and (ii), long term rainfall and temperature patterns to monitor the extent and the effect of climatic variations. Among the 34 deserts, Taklimakan has consistently the lowest NDVI, while Tanami has the highest NDVI during the entire monitoring period. The Asian Kavir and Kharan deserts have the lowest vegetation cover; Tanami has the highest vegetation cover. Out of 34 deserts, Gobi, Kalahari, Margo, Mu Us, Simpson, Strzelecki, Taklimakan and Thar deserts have shown an increasing trend in vegetation cover. While, Chalbi, Patagonian and Sonoran deserts have shown a decreasing trend. Thar, Sechura and Sahara have shown an increasing trend in precipitation, while Namib has shown an opposite trend. 31 deserts have shown an increasing trend in the temperature. Present study is important as changes in the ecological conditions of the deserts have a profound impact on the land surface albedo, surface energy balance, regional climate, carbon sequestration, biodiversity, and global dust emissions.