Desertification is advancing at different speeds depending on the area, but its impact is already evident: from forest belts containing dust in Asia to pilot projects in the southeastern Iberian Peninsula. On this global scale, decisions about what to plant, how manage the mountain and what to do after a fire They make the difference between stabilizing soils or accelerating their degradation.
While some programs have managed to stop sandstorms and sequester carbon, others have uncovered undesirable effects on the surrounding population. Meanwhile, administrations and research centers in Spain are testing whether a active forest management and adaptive can improve water infiltration and strengthen the health of ecosystems most exposed to aridity.
A forest belt to contain the advance of the desert
Launched in the late 1970s, the Great North China Tree Belt was created to stem the spread of sandy masses such as Gobi and TaklamakanThe ecological infrastructure extended over some 4.500 kilometers, restored nearly 150.000 km² and mobilized the planting of approximately 66.000 million copies with a multi-million dollar budget.
Analysts attribute to the project a drop of around 70% in the frequency of sandstorms and a capture of nearly 5% of the country's COâ‚‚ emissions between 1978 and 2017. In other words, a green shield capable of reducing wind erosion and improving air quality in areas plagued by desertification.
This success, however, has brought with it an unexpected health cost: in nearby towns, a increase in respiratory allergies linked to fast-growing species used in reforestation. Pollen from plants such as artemisia contains at least five volatile compounds that can trigger hay fever and bronchial asthma in sensitive people.
The answer is not limited to a single species. The presence of willows and poplars In certain areas of the belt, it would have contributed to residents in adjacent areas registering a higher probability of suffering from allergy symptoms, an unforeseen toll when priority was given to rapid growth and resilience in extreme climates.
To correct the course, the authorities have announced an investment of about 747 millones de euros with two main lines: replace problematic species for other safer ones (such as plum trees or ginkgo trees) and apply advanced management techniques, including the use of phytohormones, with the aim of reduce pollen load without losing its function as a barrier against the desert.
Active forest management in Murcia to tackle aridity
The Region of Murcia has launched a pilot study framed in Interreg SUDOE 2021-2027 to test whether actively caring for and managing forests improves the availability of groundwater and resilience to prolonged droughts, with desertification as a fundamental risk. The SocialForest project has nearly €400.000, 75% co-financed by the ERDF and 25% by the Autonomous Community.
The essay is based on the Royal Navy Reserve (Burete Mountains, CehegÃn), a public forest included in the Natura 2000 Network and classified as a SCI, where the Aleppo pine (Pinus halepensis) predominates. This area was chosen due to its extreme conditions, which make it a natural laboratory for evaluating the effectiveness of different forestry treatments.
Two plots have been delimited between 15 and 20 hectares: one with forest improvement interventions and another without interventions to serve as a control. Researchers and technicians will compare variables such as soil's ability to retain water, the health status of the trees, pest resistance, soil erosion and the risk of fires, with a work horizon that extends until December 2026.
The hypothesis is known: a active management It optimizes light, water and nutrients, promotes vigorous growth of the remaining trees and prevents their progressive replacement by most flammable bush, a process that accelerates environmental degradation and, ultimately, desertification. The results could be transferred to other public forests if the benefits are confirmed.
The SocialForest consortium integrates nine entities from Spain, Portugal and France: the Region of Murcia (leader), the Universitat Politècnica de València, INRAE ​​Center Nouvelle-Aquitaine-Bordeaux, the Associação para o Estudo e Defesa do Património de Mértola, the Forestry Association of Soria, the Université Toulouse III – Paul Sabatier, the Junta de Castilla-La Mancha, the Portuguese company EDIA (Alqueva) and the technological cluster Xylofutur.
Fires, restoration and prevention to stop desertification
After major fires, the landscape becomes more exposed: erosion increases, sediment drag multiplies with the first rains and water quality is compromised. Forestry engineers recommend starting the process immediately. restoration of the territory to break the spiral that leads to desertification.
In the short term, it is advisable to restore access and water points because the initial precipitation episodes can double or triple the sediment input, clogging reservoirs and causing floods. At the same time, it is advisable to protect the soil with mulches of plant remains or physical barriers while the severity of the damage and the capacity for natural regeneration are assessed.
Removing burnt wood requires discretion: in some places it will be essential for safety and operability, and in others it is convenient leave the biomass as a soil retention and defense structure to prevent runoff from carrying away nutrients.
In the medium and long term, the objective is to design a mountain resilient to climate change and future fires: selective reforestation When necessary, prioritize species adapted to new conditions, favor natural regeneration and promote mosaics with different species, ages and structures to break the continuity of the fuel.
These measures gain strength if they are integrated owners, local entities and administrations from the beginning. Investing in active forest management means prevent fires, combat desertification and strengthen the rural fabric for future generations.
Ongoing prevention is also key: turning off one hectare can cost up to 15.000 Euros, while preventing it is around 400. To reduce the risk and severity of fires that accelerate aridity, there are five well-known practical levers:
- Reduce fuel with planned clearing and cleaning.
- Recovering grazing as a biological firewall that keeps the scrub at bay.
- Apply prescribed burns and silvicultural treatments in safe times.
- Improve surveillance with early detection (towers, drones and satellites).
- Maintain life in the territory: inhabited villages take care of the landscape and reduce risk.
The accumulated experience points in the same direction: combining well-designed green infrastructure Adaptive forest management and evidence-based post-fire restoration can contain erosion, restore soils, and reduce the drivers of desertification, all while maintaining the health of the communities living alongside the forest.
