Although the effects of non-grazing and heavy grazing on vegetation structure have been extensively studied in a wide range of ecosystems, the effects of moderate grazing on desert land are still largely unknown. Many management opportunities exist for increasing forage intake. In order to determine an optimal management method of desert rangelands with high heritage value, we examined the respective effects of heavy grazing, moderate grazing and non-grazing on total vegetation cover, species richness, the Shannon-Wiener diversity index and rangeland productivity. Sampling was done from 2010 to 2012 (from the second year after treatments were imposed) using permanent transects under different grazing intensities. While total vegetation cover, species richness, Shannon-Wiener diversity index, species composition and primary production were significantly greater on the ungrazed site and significantly weaker on the heavily grazed site, in contrast, moderate grazing had no significant effect on total vegetation cover, species richness, Shannon diversity index, species composition and primary production. These studies suggest that desert rangelands plant communities in general lack response to moderate grazing disturbance, and if managed properly they can provide a valuable source of feed for livestock.

Desert rangelands are characterised by low and highly variable rainfall regime, low forage production and high heterogeneity in the distribution of natural resources. This study was carried out in the desert rangelands of Tunisia to evaluate the response of different rangelands to annual rainfall in terms of aboveground net primary production (ANPP) and rain use efficiency over a 10‐year period (2003–2012). In general, ANPP values were relatively low (123 kg DM ha−1 y−1) but would tend to increase with increasing annual rainfall for all rangeland types. The highest value of ANPP was observed from Stipagrostis pungens and Hammada shmittiana communities (sandy‐soil) during the wet year 2011. In contrast, rain use efficiency tends to decline with the highest annual rainfall and varies among rangeland types and with an average of 1·9 kg DM ha−1 mm−1 y−1. Rain use efficiency tended to be higher during dry years and lower during wet years and tended to be higher on S. pungens and H. shmittiana (sandy‐soils) and lower on Helianthemum kahiricum (loamy soils). Therefore, understanding how rainfall affects productivity in rangelands is critical for predicting the impact of land degradation on the functioning of these ecosystems. It can be used to explain production decline associated with desertification as well as to assess rangeland conditions. Copyright © 2015 John Wiley & Sons, Ltd.

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Purpose The purpose of this paper is to illustrate the benefits of reintroducing traditional grazing systems practices for improving arid rangelands. Grazing is the most extensive land use in southern Tunisia, but the rangelands have suffered many decades of severe degradation due to profound socioeconomic changes and the emergence of an agro-pastoral society in place of the former pastoral one. Traditional grazing systems (gdel and herd mobility), which had historically allowed for grazing deferment and control of grazing livestock were abandoned. Yet grazing management strategies are important tools to sustain integrated livestock rangeland production systems in dry areas in the face of ongoing climate change and human pressure. Design/methodology/approach This study assesses the revival of traditional best practices of rangeland resting in a representative community. Total plant cover, species composition, flora richness and range production were determined in six rangeland sites subjected respectively to one, two and three years of rest; one and two years of light grazing after rest; and free grazing (control). Findings Results showed that dry rangelands keep their resilience to the negative effects of climate change once human pressure is controlled. A maximum of two years of rest is enough to sustainably manage the rangelands in southern Tunisia, as this protection showed considerable and positive effects on the parameters scored. Originality/value The revival of the traditional best practices under new arrangements adapted to current biophysical and socioeconomic conditions would be an excellent tool to mitigate the negative effects of frequent droughts and reduce the animal feed costs that poor farmers face.

The desert and Saharan rangelands of southern Tunisia are an important source of feed for grazing herds. Productive management of these rangelands has been found impossible if the natural vegetation becomes severely degraded unless restoration work is undertaken. The main objective of our study was to eval uate the impact of protective fencing for periods of one, two and three years duration on Saharan vegetation at three sites characterised by sandy and limestone (skeletal) soils. Results showed that vegetation covering, measured in terms of species richness and plant biomass, increased with time of protection from grazing, and that covering was more marked on the sandy substrate than on the limestone substrate, while under heavy grazed area the opposite occurred, thus I can deduce that the sandy soil are more productive than the lime stone soil, whereas the latter are more resistant to animals trampling.

Plants are important components of any rangeland. However, the importance of desert rangeland plant diversity has often been underestimated. It has been argued that desert rangelands of Tunisia in good ecological condition provide more services than those in poor ecological condition. This is because rangelands in good condition support a more diverse mixture of vegetation with many benefits, such as forage for livestock and medicinal plants.Nearly one-quarter of Tunisia, covering about 5.5 million hectares, are rangelands, of which 87% are located in the arid and desert areas (45% and 42%, respectively). Here, we provide a brief review of the floristic richness of desert rangelands of Tunisia. Approximately 135 species are specific to desert rangelands. The predominant families are Asteraceae, Poaceae, Brassicaceae, Chenopodiaceae, and Fabaceae. These represent approximately 50% of Tunisian desert flora.

Natural rangelands occupy about 5.5 million hectares of Tunisia’s landmass, and 38% of this area is in Tataouine governorate. Although efforts towards natural restoration are increasing rapidly as a result of restoration projects, the area of degraded rangelands has continued to expand and the severity of desertification has continued to intensify. Any damage caused by disturbances, such as grazing and recurrent drought, may be masked by a return of favorable rainfall conditions. In this work, conducted during March 2018, we surveyed the botanical composition and species diversity of natural rangelands in Tataouine in southern Tunisia. The flora comprised about 279 species belonging to 58 families, with 54% annuals and 46% perennials. The Asteraceae family had the greatest richness of species, followed by Poaceae, Fabaceae, Amaranthaceae, Brassicaceae, Boraginaceae, Caryophyllaceae, Lamiaceae, Apiaceae, and Cistaceae. Therophytes made the highest contribution, followed by chamaephytes and hemicryptophytes. Of all these species, 40% were palatable to highly palatable and more than 13% are used in both traditional and modern medicine.