In the Mediterranean, cows,
sheep and goats share the same forage areas and are separated temporally and behaviorally (Vallentine 2001) by different foraging preferences. Cows are grazers that consume grasses and avoid woody species, sheep are intermediate foragers that consume grasses, forbs and woody species, and goats are browsers that consume forbs and woody species and avoid grasses (Vallentine 2001). Goat foraging period (May–June; www.selleckchem.com/products/NVP-AUY922.html Portuguese Associations for Bovine and Microtubule Associated inhibitor Ovine and Caprice livestock production, unpublished data) coincides with the time when young woody riparian plants have reached the sapling stage and become more conspicuous, making them more vulnerable to herbivores. The results showed that strictly riparian plant richness was positively affected by fragmentation (higher number of patches) of the surrounding landscape, and it was negatively affected by the presence of patches of different landscapes (as measured by the landscape diversity indexes). Three factors may contribute to this pattern: the total area covered check details by the different land covers, diversity of land covers and their density. First, the results indicate that fewer riparian plants are found when larger sclerophyllous patches
surround the riparian ecosystem, suggesting that these fewer larger patches may be contributing greater numbers of sclerophyllous plant propagules to the riparian ecosystem. Furthermore, patches of a variety of different land covers (holm oak, cork oak woodlands, olive yards, etc.) have a very negative effect on the strictly riparian plant richness, as the total riparian community is inundated by propagules from different types of plant species, which may have different establishment success rates in the different open patches within the riparian area. Finally, if the surrounding land cover is mainly holm oak woodlands, the frequency of seeds and propagules may actually be reduced since this landscape is characterized by a sparse canopy that is experiencing a decreasing trend in recruitment (Plieninger et al. 2004; Ramirez and Diaz 2008), currently below replenishment rates, and holm
oak woodlands do not seem to be exporting seeds elsewhere. This can also explain the negative effect of the area of agriculture on the richness of sclerophyllous plants in the riparian ecosystem. As more agricultural find more land exists around the riparian area, reduced sclerophyllous seeds exist in the seed pool to colonize the riparian zone. Data quality assessment The quality of the interpretation of the results also depends upon the quality of the data input to the models. It is acknowledged that some underestimation may have occurred of species richness as some species lacked key characters that allowed their differentiation. Even though this underestimation may make comparison of these results to those of other authors more difficult, its effect is likely negligible.