Oases expand but face threats from desertification and climate change

Oases expand but face threats from desertification and climate change
by Clarence Oxford
Los Angeles CA (SPX) Apr 23, 2024

Despite covering only about 1.5% of the world's land, oases are vital water sources for dryland regions, supporting 10% of the global population. Recent studies, however, warn that these critical habitats are increasingly vulnerable to desertification and climate change. Over the past 25 years, while some oases have expanded due to human intervention, others have diminished due to environmental pressures.

"Oases are crucial, yet until now, we've lacked comprehensive data on their global distribution," stated Dongwei Gui, a geoscientist at the Chinese Academy of Science who led the new study. The research underscores the importance of oases in achieving United Nations Sustainable Development Goals and in promoting sustainable development in arid areas.

The study tracked the expansion and contraction of oases worldwide, noting an overall growth of 220,149 square kilometers from 1995 to 2020, primarily through projects in Asia aimed at extending these areas. However, these gains are counterbalanced by a loss of 134,300 square kilometers due to desertification, leading to a net increase of 86,500 square kilometers over the studied period.

Oases, which are mainly found in Asia and Australia, provide essential water for numerous desert-based forms of life. They arise either from underground water reaching the surface or from mountain runoff, creating lush, vegetated areas within drylands. The recent findings, derived from satellite data and land surface classifications from the European Space Agency's Climate Change Initiative Land Cover Product, reflect significant changes in land use and oasis health influenced by both human activity and climate factors.

Gui's team found that human efforts have largely driven the increase in oases, particularly in China, where over 60% of the growth has been recorded. For instance, in China's Xinjiang Uygur Autonomous Region, where the majority of the population lives within oases, conservation efforts have seen an expansion of 16,700 square kilometers.

Conversely, the adverse effects of desertification have led to significant losses in oasis areas, impacting an estimated 34 million people globally. The research highlights the delicate balance between expansion due to human activities and natural and human-induced reductions in viable oasis areas.

The study also points to the need for improved water management, sustainable land use, and efficient water use to maintain oasis health amid changing climate conditions. Gui emphasized the importance of international cooperation in managing these vital ecosystems, as they often span multiple countries within a single river basin.

Research Report:Distribution and growth drivers of oases at a global scale