23 May 2024

Climate mitigation is the first barrier against erosion in Tibet


Climate change will be decisive in increasing erosion in the Tibetan Plateau, a Chinese study finds. So curbing rising temperatures becomes decisive

by Matteo Cavallito


Focusing on climate mitigation is especially needed to effectively counter soil erosion in the Tibet Plateau. This strategy, in fact, seems to be more effective than direct interventions on vegetation. Vegetation improvement, not surprisingly, is effectively compromised by global warming itself. This is supported by a study conducted by a group of scientists from the Research Center for Eco-Environmental Sciences in Beijing.

The research takes on important significance by shedding light on a phenomenon that is not yet fully understood and that affects a prime environment. The Tibetan Plateau, whose role in regulating summer rain in southern China is well known to scientists, has long faced increasing water erosion, the authors recall.

The study

“Water erosion is a wide ecosystem degradation threat for the Qinghai-Tibetan Plateau (QTP) region and surrounding areas ,” the study explains. In this context, global warming is expected to result in a wetter climate and more lush vegetation growth. The latter effect, in particular, could even help counter erosion. Provided, however, that other phenomena related to climate change (increased precipitation, for example) do not, at the same time, end up counteracting it. Information on these dynamics, however, is currently very limited.

To assess the phenomenon, therefore, the authors used a system called RUSLE or Revised Universal Soil Loss Equation, which has already been used in other research on the subject.

The equation takes into account several factors such as expected crop loss, rainfall and runoff, soil erosion tendency, steepness and length of a mountain slope, and crop management. In this way, the potential annual soil loss can be estimated depending on the variables considered.

Climate mitigation is crucial

The authors then estimated water erosion by simulating future changes under different scenarios. In this way they were able to assess the role of climate change and vegetation growth in counteracting erosion itself by weighing precisely the contribution of these two factors.

The research, they explain, showed “intensified erosion and that the benefits of vegetation improvement to erosion control was impaired under climate change.”

Indeed, the numbers that emerged show an increase in erosion under a scenario of rising temperatures. “Although more considerable vegetation improvement could occur under high climate forcing, there may also be more intensified rainfall erosivity and water erosion across the Qinghai–Tibet Plateau,” the study continues. The results, consequently, “suggest that mitigating climate change rather than vegetation improvement is essential to address climate-dominated ecosystem degradation threats such as water erosion.”

Tibetan Plateau is of increasing interest to scientists

Much attention in recent years has been devoted, not surprisingly, to the climatic dynamics affecting the Tibetan Plateau. Recent research published in the journal Advances in Atmospheric Sciences, for example, has unraveled the mechanisms underlying the precipitation regulation capacity exerted by this area. According to the study, in particular, the heat source of the Tibetan plateau would strengthen the transport of water vapor to the eastern part of the country, leading to heavier rainfall in the Yellow River Valley region and northern China.

Another study from Beijing Normal University published in the journal Nature Climate Change also highlighted the importance of the complex network of interactions between the atmosphere, oceans, land, ice and biosphere that would occur through the ability of certain critical phenomena to trigger certain effects in another area of the Planet. Numbers in particular had pointed to the existence of a connection between the anomalous temperatures recorded over the past 40 years in the Amazon and those detected just in Tibet during the same period.