Nature-Based Solutions (NbS) for the Ecological Reclamation of Abandoned Volcanic Tuff Quarries and Flood Risk Mitigation: The Case of Artik, Armenia

In the high mountains of the Caucasus, the land tells a story of two very different forces: the slow, patient work of nature building soil and forests, and the sudden, violent disruption of human industry. When people dig deep into the earth to extract stone, they often leave behind landscapes that are stripped bare, steep, and unstable. These abandoned quarries are not just eyesores; they are dangerous. Without the protective blanket of plants and rich soil, rain cannot soak in. Instead, it rushes down the slopes, picking up loose dust and rocks, turning into flash floods that can destroy towns downstream. For decades, scientists and engineers have debated how to fix these scars. The old way was to build concrete walls and channels, hard structures meant to fight the water. But a growing body of work suggests that the best way to tame a wild landscape is to help it heal itself, using the tools of nature rather than just the tools of engineering. This approach, known as Nature-Based Solutions, involves reshaping the land to be stable, rebuilding the soil, and planting the right mix of trees and shrubs to hold everything together.

In the town of Artik, Armenia, a team led by environmental specialist Aida Sargsyan put this idea to the test on a massive scale. For years, the surrounding hills had been carved up by unregulated mining of volcanic tuff, a soft rock used for building. The result was a fragmented wasteland of forty hectares where the ground was so steep and bare that it could not support life. During heavy rains, the water would race off these barren slopes, carrying tons of dust and debris into the city's drainage systems, causing severe flooding and damage. The local authorities realized that concrete walls alone could not solve a problem rooted in the land itself. They needed to turn a hazardous industrial site back into a functioning forest.

The project began with a dramatic transformation of the terrain itself. The original site was a nightmare of vertical cliffs, some rising as high as eighty-five degrees, and piles of loose, unstable rock. Heavy machinery moved in to reshape the entire forty-hectare area. Instead of leaving the steep, dangerous faces, the team cut them back and graded them into a series of gentle, stable terraces with slopes between fifteen and twenty degrees. This simple act of re-engineering the land's shape removed the immediate risk of landslides and slowed the speed of water running down the hill. Once the ground was stable, the team faced a second challenge: the soil was gone. What remained was raw, sterile volcanic rock that was too alkaline and compacted for any plant to survive. To fix this, they brought in thousands of tons of composted manure and specific mineral fertilizers, mixing them into a new topsoil layer twenty to thirty centimeters thick. This process turned the dead, dusty rock into a living medium capable of holding water and nutrients.

With the land reshaped and the soil revived, the team planted nearly thirty thousand saplings. They did not choose just one type of tree, which can be risky if a disease strikes, but instead created a mixed forest. They planted Scots pine, Caucasian oak, European ash, and various junipers and shrubs. Each species was chosen for its ability to survive the harsh, cold, and dry conditions of the high altitude. The pines and oaks were planted to anchor the slopes with deep roots, while the ash trees grew quickly to catch rain and the shrubs held the edges of the terraces together. To help these young trees survive their first few critical years, a dedicated irrigation system was installed to provide water during the dry summer months. At the same time, along the gullies where water naturally flowed, the team built porous stone walls called gabion check dams. These were not solid concrete barriers but flexible cages filled with local stones. They were designed to slow down the rushing water, trap the heavy rocks and debris, and let the clean water pass through safely.

Three years of monitoring revealed that the transformation was not just visual, but deeply chemical and physical. The soil, which had previously been a sterile, highly alkaline dust with almost no organic matter, had changed. The organic content rose significantly, and the soil's acidity balanced out to a neutral level that plants could thrive in. The trees took hold, with survival rates reaching between seventy-two and eighty-two percent across the different species. The forest canopy began to intercept rain, and the roots started binding the soil, stopping the wind from blowing dust into the air. Perhaps most importantly, the hydrology of the site changed completely. The porous stone dams and the rough, vegetated surface of the terraces slowed the water down so effectively that the transport of coarse sediment into the city's drainage infrastructure was reduced by 100%. The water that once tore through the landscape as a destructive torrent now moved gently, filtered by the new ecosystem.

The results from Artik demonstrate that turning a dangerous mining scar into a safe, productive forest is possible, but it requires a coordinated effort that goes beyond simple planting. It demands a fundamental change in the shape of the land, a chemical rebalancing of the soil, and a strategic mix of vegetation. The project showed that by working with the natural processes of erosion and growth, rather than trying to fight them with rigid structures, communities can protect themselves from the increasing threats of climate-driven floods. The abandoned quarries of Artik are no longer a source of danger; they have become a self-sustaining forest park that shields the town below, proving that even the most damaged landscapes can be restored to health.