A new review published in Trends in Plant Science on Oct. 31 highlights deep-rooted plants (DRPs) as essential, yet often overlooked, guardians of the world's arid lands. Led by Prof. ZENG Fanjiang, the study redefines deserts and drylands as active ecological frontiers, with DRPs at the forefront of stabilization and climate mitigation.

"Deep-rooted plants are not just plants; they are ecological engineers," said Dr. Akash Tariq, the study's first author. Species such as Alhagi, Tamarix, and Haloxylon act as natural barriers against desertification. By accessing deep groundwater reserves, these species stabilize soil, foster the formation of fertile microhabitats, and sustain entire ecosystems even in the most challenging environments.

The review identifies three key DRP adaptations: fast-growing taproots that penetrate over 60 meters deep, a hydraulic lift that redistributes water to surrounding vegetation, and water-conserving leaf structures. These features enable DRPs to flourish in conditions that are inhospitable to most plants.

The study also highlights the substantial socio-economic value of DRPs. They provide essential livestock forage, enable ecotourism ventures such as the "Desert Highway" in the Taklamakan Desert, and have supported human livelihoods for centuries. Initiatives such as Africa's "Great Green Wall" project have generated significant revenue by utilizing these species.

However, the researchers warn that DRPs face escalating threats from climate change and human impact. Higher temperatures, overgrazing, and, above all, excessive groundwater extraction endanger DRPs, threatening their survival and the stability of their ecosystems.

Dr. Akash Tariq explained that groundwater depletion directly threatens these plants. When water tables fall below their roots, DRPs lose their growth and carbon sequestration capacity, leaving the land more susceptible to degradation.

Researchers urge an integrated conservation approach that includes sustainable water management, such as drip irrigation; rotational grazing policies; the establishment of protected areas; and remote sensing for plant monitoring. They stress the importance of aligning these actions with global frameworks, such as the UN Convention to Combat Desertification and the Sustainable Development Goals.

"DRPs are essential for climate adaptation in drylands," said Dr. Akash Tariq. Safeguarding their potential is both an ecological and socio-economic imperative. Investing in these natural guardians strengthens the resilience and sustainability of arid lands worldwide.

The review urges scientists, policymakers, and land managers to prioritize deep-rooted plants and maintain their essential role in protecting the world's arid ecosystems.

Deep-rooted plants and carbon sequestration in arid ecosystems. (Image by XIEG)