Haymaking of Stipa in pre-Saharan Tunisia: opportunities to restore private arid lands

摘要

A number of ecological restoration projects black-box the rationale of land users. This has particularly important consequences in less affluent societies such as in pre-Saharan Tunisia (average annual rainfall 100-200 mm), a showcase of accelerateddesertification since the 1950s. Here, agriculture has invaded the former common rangelands, turning them into a patchwork of eroded private land (cereal fallows and olive orchards) and overgrazed range leftovers. Lack of adapted perennial plant cover is a major cause of the low productivity of private land. In order to reverse the desertification process, restoration ecologists suggest that cultivated land should return to rangeland. However, this reconversion, be it to private or to common rangeland,is not realistic, in the first place because the social demand concentrates heavily on (privately owned) cultivated land. In this context, certainly the use of native species (mainly palatable perennial grasses and legumes) is ecologically sounder thanthe continuation of an impoverished and marginally productive form of Mediterranean agriculture. But the social acceptance of these native species within private lands depends on whether people can harvest them in another way than through grazing. Our idea is that instead of converting these areas into rangeland, haymaking of palatable perennial grasses can provide the key to their ecological restoration. Summer drought is a major problem for Mediterranean animal husbandry. In Presaharian Tunisia, dry summer forage is of vital importance for the survival of livestock until the first winter rains. Hence every spring, local agropastoralists make hay from several range species. Though never fully described, this practice has undergone profound changes since the 1950s. How was haymaking done before the 1950s? Why did it change? Is there any opportunity to re-establish it within private lands? We carried out 11 in-depth interviews with local elderly agropastoralists from different regions, renowned for their ecological working knowledge. We focused on Stipa lagascae R. & Sch. (hereafter called Stipa), a flagship species of restoration ecologists for its grazing value and grazing resistance, but not for its value as a hay plant. The interviewees told us unanimously that until the 1950s three plant groups were systematically hayed: (1) annuals that are ubiquitous in rainy years but absent in dry years; (2) fibrous perennial grasses of low grazing value that colonize rocky relief, gypsous crusts and movingsands; and (3) Stipa, which can only be hayed if not grazed during the preceding winter. Haymaking of Stipa, the most precious resource, was special. It was part of the transhumance calendar, according to which people and animals spent the dry part of the year in villages near permanent access to water. If the winter rains were abundant, entire households left the villages to camp in their traditional grazing lands on the border of the true Sahara. Only there, far away from permanent settlements, populations of Stipa were still extensive enough to provide hay at the end of the grazing season. Nowadays, only annuals and fibrous perennial grasses remain commonly hayed by settled agropastoralists. These species have spread because of accelerated soil cultivation and erosion caused by a demographic explosion and tremendous socio-economic changes (Tunisia gained independence from France in 1956). The combination of Stipa decline and the perspective of a better life lead people to give up transhumance and Stipa haymaking, and to focus on private land ownership near their villages. Despite the current availability of commercial feeds, agropastoralists still try to reduce monetary expenses by feeding their animals from locally gathered plant material. Although the interviewees unanimously appreciate the Stipa hay, they cannot conceive growing Stipa by themselves. Still, haymaking of Stipa, and possibly also other grasses (even more rarified), holds prom