Qualification of Rangeland Degradation Using Plant Life History Strategies Around Watering Points in Southern Tunisia

Abstract

In this reserch we review the effects of animal activities on plant life history strategies (CRS) around watering points using phyto-ecological studies and vegetation cover data. The objective of this study was to understand the impact of disturbance degree simulated by distance from wells on CRS strategies (Grime types). The main results indicate that annualisation is a reality. We show the dominance of RS-species in the more disturbed sites (nearest transect from watering points), CRS- and CS-species at medium disturbance and CS- and S-species in lower disturbance sites (further from water). The floristic homogenisation is discernible at long period of exploitation. With lower grazing disturbance, Stipagrostis pungens can appropriately survive but it cannot tolerate the high degradation levels.

Acceptability of plant species along grazing gradients around watering points in Tunisian arid zone

“…Tongway et al (2003) revealed significant change in resources distribution processes at different grazing intensities and show that the ''piosphere'' effect is discernible even on a radius of 1-3 km from water. It was shown that the ''piosphere'' extend is more remarkable on sandy substratum as compared to stony one (Tarhouni, 2008;Tarhouni et al, 2007).…”

“…Gradients of grazing over increasing distances from watering points have been used extensively in rangeland research to look at the impact of livestock on rangeland vegetation (Kinloch and Friedel, 2005a, b;Tarhouni, 2008;Tarhouni et al, 2006Tarhouni et al, , 2007Thrash, 2000). Distance from water can be used as a surrogate of grazing pressure -high near water and low away from water (Ludwig et al, 2001).…”

“…However, Feoli et al (2002) reported that grazing activity influences the vegetation physiognomy more than its composition. Changes in vegetation along a grazing gradient can be defined as a decrease in the perennial palatable plants and the dominance of unpalatable or annual plants in the vicinity of wells (Heshmatti et al, 2002;Tarhouni et al, 2007;Todd, 2006). Likely, Geerken and Ilaiwi (2004) showed a decrease of perennial recovery, an increased mortality of woody plants and their replacement by less productive species under overgrazing.…”

Plant species composition and diversity depending on piospheres and seasonality in the southern rangelands of Kenya

“…Piospheric studies on species composition, richness, and diversity indices have been done in most parts of the world including Australia (Landman et al 2012), Asia (Shahriary et al 2012), Southern Africa (Todd 2006), Northern Africa (Tarhouni et al 2007), and Uganda (Egeru 2014;Egeru et al 2015). Nevertheless, there have been no studies conducted in Kenya, especially in the southern rangelands where water interventions have been widely undertaken to alleviate water shortage and enhance pastoral livelihoods (Opiyo et al 2015).…”

Impact of Livestock Exclusion on Sidi Toui National Park Vegetation Communities, Tunisia

“…This is not general for all vegetation units because many plant species tolerate degradation and progressively disappeared when protected. For example, Stipagrostis pungens tolerates sand movement [24], but it cannot tolerate heavy disturbances such as grazing and trampling [25]. The rarefaction of this species is still remarkable after soil fixation and other plants begin their development and replace it ( Table 2).…”