17 June: World Day against Desertification
The 63 million hectares natural barrier formed by North African dry steppes between the Sahara and the Mediterranean mountains and coast, is playing an undervalued and decisive role in preventing the advance of the desert.
Working against the desert
The extensive grasslands characterised by a perennial mega-herb known as esparto or halfa grass (Stipa tenacissima), can resist a great variation of temperatures: from -20ºC in winter to more than 40ºC in summer; and respond rapidly to short water pulses, such as late summer rainfall events in low (150-400 mm) and very irregular precipitation conditions. The inherent water constraints of the Mediterranean climate and the location of the region in the transitional zone with the deserts of Africa and West Asia may result in dramatic changes if the climate band shifts a few degrees of latitude, creating new desert areas. And this is affecting not only North Africa, but also Southern Europe, including Spain.
Stipa tenacissima creates “hotspots” of favourable soil conditions and microclimate, the so-called “resource islands” or “islands of fertility”, facilitating the establishment of shrubs and tree species in the semi-arid steppes, a very important prospect when planning restoration actions in degraded steppe land. Stipa tenacissima tussocks modify the availability of resources such as light, nutrients and water in semi-arid steppes through the amelioration of the microclimate, the improvement in the soil structure and depth, the increase in soil moisture and water infiltration, and carbon and nitrogen storage.
In spite of the vital role played by the steppes in North Africa against desertification, they are often regarded as wasteland, and are therefore exposed to extreme degradation caused by humans: overgrazing, over-harvesting of wood and plants, land conversion into agriculture, etc. The synergetic combination of climate change together with these rapid changes in land use is leading to vegetation loss, soil alteration by eolian sand mobilization, the encroachment of inhabited areas and the impoverishment of the natural and social capital of the North African Steppes. As mangroves on the coast reduce the risks of natural disasters such as tsunamis, esparto serves the same purpose against the advance of the desert.
A look at its economic values
It seems however that only nomadic pastoral societies and botanists care about Esparto. Yet, strangely enough, one of the most valuable items for people may contain esparto: money in the shape of our beloved bank notes. Esparto pulp is used by paper manufacturers to produce first class stationery; highly important printed and written documents required to resist a good deal of handling, such as bank notes, contain Esparto. But it is also a basic material for electrical insulation paper, filter paper, cigarette paper, aeronautical products, and construction materials, including bio-architecture, which is an important component of plaster ceilings.
Rural economies also have Esparto as a complementary source of income, mainly based on handcraft production. Women in particular, are responsible for the care and harvesting of this plant, providing livelihoods and a source of income to many families. Moreover, new technologies are using Esparto carpets to combat soil erosion and facilitate restoration of degraded land. Organic mats made of esparto and straw are currently being used in restoration projects under heavily degraded soils, as they provide stability to the planted seeds during the first years, and as they melt with the organic soil after few years, they produce no waste.
Next time you open your wallet to get a bank note, think about how essential esparto semi-arid steppes are to maintain the capital and wellbeing of Mediterranean countries: they help stop desertification, provide income for rural communities and the core of your money!
The IUCN Centre for Mediterranean Cooperation is currently working on an esparto restoration project in the framework of the IUCN North Africa Programme. Esparto can also be found in the South of Europe, in particular in Spain in semi-arid areas of Murcia and Almeria.
For more information, please contact:
Pedro Regato, Senior Programme Manager, IUCN-Med, Tel: +34.952 028430, ext. 109