Large grazers modify effects of aboveground–belowground interactions on small-scale plant community composition

Aboveground and belowground organisms influence plant community composition by local interactions, and their scale of impact may vary from millimeters belowground to kilometers aboveground. However, it still poorly understood how large grazers that select their forage on large spatial scales interact with small-scale aboveground–belowground interactions on plant community heterogeneity. Here, we investigate how cattle (Bos taurus) modify the effects of interactions between yellow meadow ants (Lasius flavus) and European brown hares (Lepus europaeus) on the formation of small-scale heterogeneity in vegetation composition. In the absence of cattle, hares selectively foraged on ant mounds, while under combined grazing by hares and cattle, vertebrate grazing pressure was similar on and off mounds. Ant mounds that were grazed by only hares had a different plant community composition compared to their surroundings: the cover of the grazing-intolerant grass Elytrigia atherica was reduced on ant mounds, whereas the relative cover of the more grazing-tolerant and palatable grass Festuca rubra was enhanced. Combined grazing by hares and cattle, resulted in homogenization of plant community composition on and off ant mounds, with high overall cover of F. rubra. We conclude that hares can respond to local ant–soil–vegetation interactions, because they are small, selective herbivores that make their foraging decisions on a local scale. This results in small-scale plant patches on mounds of yellow meadow ants. In the presence of cattle, which are less selective aboveground herbivores, local plant community patterns triggered by small-scale aboveground–belowground interactions can disappear. Therefore, cattle modify the consequences of aboveground–belowground interactions for small-scale plant community composition

The impact of grazing on forage quality of the herbaceous vegetation in the Mamora cork oak forest, Morocco

Reports on research conducted in the Mamoro cork oak forest of Morocco to describe the impacts of sheep grazing in March, April, May and June of 1987 and 1988 on seasonal changes in forage quality of the herbaceous vegetation. The study showed that trends in herbage quality were related mainly to plant maturity. Illustrates with graphs and tablesKeywords: crude protein; forage quality; grazing; herbaceous vegetation; impact; IVOMD; Mamora cork oak forest; Mediterrean-type climate; minerals; Morocco; oak; vegetationAfrican Journal of Range & Forage Science, Vol. 14, Iss 1, p.12-1

Adaptation of Methods and Technologies in Agriculture and Forestry, in Water Resources Economy, and Changes in Biosphere

International audienceAgroforestry (AF) systems where trees are managed together with crops and/or animal production systems in agricultural settings seem to give promising results in making agriculture more productive and resilient, in particular towards climate change. Thanks to the economic and environmental benefits explained below agroforestry has been evolving, both as a land use practice and as a science in recent years