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Atriplex halimus L. is a valuable fodder shrub that has been widely used in arid Mediterranean regions. However, its response to several cumulative years of grazing management remains uncertain. Accordingly, we conducted a three-year experiment in south-eastern Spain to analyze the influence of repeated seasonal (winter-spring) sheep browsing on young A. halimus plants. Shrub growth, fodder and wood production, plant compactness and shoot moisture content were assessed through regular monitoring of the size of shrubs, sampling of summer shoots, and destructive procedures at the end of the experiment. Shrubs were on two closely located sites but where soil quality and water availability were different. At the better location, browsed shrubs grew less and were significantly smaller (P < 0.001) than the non-browsed saltbushes. In contrast, differences between groups were minimal where the growth conditions were poorer. In all cases, shrubs resprouted vigorously and maintained fodder production throughout the experiment. Browsing affected shrub structure, resulting in smaller but more compact plants (2.20 vs. 1.24 g dm−3, P < 0.001), but their proportion of fodder remained similar. The spring grazing increased shrub-shoot moisture content in the summer (62.5% vs. 56.0%, P < 0.001). Overall, this species responded very positively to repeated seasonal grazing.

Coronilla juncea is a leguminous shrub native to semi-arid regions of the Mediterranean Basin, particularly south-eastern Spain, and is browsed by livestock such as sheep and goats. We provide here information about this source of forage: allometric regression equations (phytovolume vs. total and forage phytomass), nutritive value and seed germination. The regression equations calculated were highly significant (r2= 0·86 for volume/total phytomass and 0·93 for volume/forage phytomass, p < 0·001). The values recorded for the in vitro digestibility of dry matter and organic matter were 65·93% and 62·13%, respectively. The optimum temperature for seed germination was 10°C. Scarification in goat rumen for 24 h increased the overall germination rate of fruit with pericarp although in sheep rumen overall germination decreased slightly. We suggest that this fodder shrub be included in programmes for land management and the rehabilitation of degraded semi-arid-to-arid ecosystems.

A comparison was made of plant cover, carrying capacity and diversity in areas of Monte vegetation at the Biosphere Reserve of Nacunan, Mendoza, Argentina, in 1982, 1984 and 1995. Treatments applied in 1981 were: control (untreated plots), selective hand-cutting, roller-chopping, and root-plowing. By 1995, woody cover was lower in root-plowed plots (27%) than in the others treatments (41–51%), and herbaceous cover was similar in treated (28–39%) and untreated areas (26%). Carrying capacity of treated areas (6–8 ha per Large Stock Unit (LSU)) was higher than in the control areas (12 ha LSU−1). Woody species diversity, quantified by the Shannon index, for both areas was similar in the study period (0·62), except in root-plowed sites in 1982 (0·0) and 1995 (1·3). Herbaceous species diversity was similar on treated (0·81) and untreated sites (1·2) in 1995. We could recommend less drastic treatments to improve carrying capacity.

This study provides data on plant density, vegetation cover, total and forage phytomass for the main rangelands and shrubs of a ‘pilot zone’ (Almeria, Spain) in the south-east of Spain. Carrying capacity has been calculated for each rangeland, and for two different levels of energy requirements: maintenance (from 0·29 to 1·28 goats ha −1 ) and production (from 0·20 to 0·88 goats ha −1 ). The nutritive value was determined for the most representative shrubs in the area