An Extended Multi-Source WEPI Framework for Mapping Wind Erosion Potential, Hotspots, and Priority Zones in Lorestan Province, Iran

In the dry, sun-baked landscapes of the world, the wind is a constant, invisible sculptor. It does not merely blow; it carries away the very foundation of life on the land. When the ground is bare and the soil is dry, gusts of air can lift the fertile topsoil, the dark, nutrient-rich layer that allows plants to grow, and scatter it into the atmosphere. This process, known as wind erosion, is a slow but relentless form of land degradation. It strips away the earth's ability to support agriculture and rangelands, turning productive land into dust. While this phenomenon is well-known in vast deserts, it also threatens the edges of these arid zones, where mountains meet the plains and where seasonal changes leave the soil exposed for brief, vulnerable windows. Understanding exactly where and when this happens is crucial for farmers, rangers, and planners who need to protect the land before it is lost forever.

For a decade, from 2016 to 2025, researchers have been watching the winds over Lorestan Province in western Iran, a region defined by its rugged mountains, diverse farms, and seasonal grasslands. A team of scientists led by Mostafa Ghasemzadeh Ortakand and Meysam Bali set out to map the invisible threat of wind erosion across this entire landscape. They did not rely on a single snapshot or a handful of field measurements, which can miss the bigger picture. Instead, they built a comprehensive digital model that acts like a weather eye, constantly scanning the region using a vast array of satellite data. By combining information about how much vegetation covers the ground, how dry the soil is, how hot the surface feels, and how strong the wind blows, they created a detailed index of erosion risk. This approach allowed them to see not just where the wind is strong, but where the land is most vulnerable to losing its soil.

The results of this decade-long observation reveal a landscape that is under constant, moderate pressure. The researchers found that wind erosion potential in Lorestan is not a rare event limited to a few dusty corners; it is a widespread condition affecting the vast majority of the province. Over the ten years studied, the average risk level remained steady, hovering in a range that indicates a persistent threat. When they broke down the land into risk categories, a striking picture emerged: more than 95 percent of the valid land area was classified as having at least a moderate risk of erosion. Only a tiny fraction of the province, less than five percent, could be considered safe from this threat. This suggests that the entire region exists in a state of chronic vulnerability, where the soil is frequently on the brink of being stripped away.

The danger is not uniform throughout the year; it breathes with the seasons. The study showed that the risk is lowest during the cooler, wetter months of winter and spring, when the ground is protected by moisture and plant growth. However, as the heat of summer arrives, the landscape transforms. The vegetation dries out, the soil loses its moisture, and the ground becomes bare and exposed. During these warm months, particularly in summer and early autumn, the risk of wind erosion spikes significantly. The data indicates that the summer season is the most critical time for the land, with erosion potential reaching its peak. This seasonal surge is driven by a combination of natural climate cycles and human activity, such as the clearing of fields after harvest and the grazing of livestock, which leave the soil bare just as the winds are strongest.

To understand what drives this erosion, the researchers looked closely at the ingredients that make up their risk index. They discovered that the two most powerful factors are the loss of protective vegetation and the exposure of bare soil. Together, these two elements account for nearly half of the total erosion risk. When plants are removed or die back, the wind has nothing to catch against, and the soil is left naked to the elements. While other factors like the texture of the soil, the steepness of the slopes, and the amount of rainfall play a role, they are secondary to the simple fact of whether the ground is covered or bare. This finding points to a clear path for protection: keeping the soil covered with plants is the most effective way to stop the wind from taking it.

The study also looked for signs that the problem is getting worse over time. They searched for areas where the risk was rapidly increasing, expecting to find a landscape in the midst of a sudden crisis. Instead, they found something more subtle and perhaps more concerning. While there were a few small, isolated spots where erosion risk was climbing, the vast majority of the province did not show a rapid, accelerating trend. The risk was not suddenly exploding; it was already high and staying high. The land was not degrading in a new, dramatic way, but rather suffering from a long-standing, persistent condition. The most dangerous areas were not necessarily the ones changing the fastest, but the ones that had remained vulnerable for the entire decade.

This distinction led the researchers to a new way of thinking about how to manage the land. Rather than focusing only on finding the few places where the problem is getting worse, they identified "hotspots"—large, connected areas where the risk is consistently high and clustered together. These zones, which cover thousands of square kilometers, represent the true priority for intervention. The researchers created a map that highlights these persistent danger zones, combining the long-term risk levels with the areas where the danger is most concentrated. This map serves as a guide for where to focus efforts, such as restoring vegetation, managing grazing, or stabilizing the soil. It tells planners that the most urgent work is not just in the places that are changing, but in the places that have been suffering for a long time.

The framework developed by this team offers a powerful tool for the future. By using freely available satellite data and advanced computing, they created a method that can be copied and used in other dry, mountainous regions around the world. The study proves that we do not need to wait for a disaster to happen to know where the land is fragile. We can see the vulnerability clearly, understand the seasonal rhythms that drive it, and identify the specific areas that need help the most. In Lorestan, and potentially in other regions facing similar challenges, this knowledge allows for a shift from reacting to dust storms to proactively protecting the soil. The wind will always blow, but with a clear map of the risks, the people of the land can ensure that the soil remains where it belongs, holding the foundation for life against the force of the air.