Plant Ecology and Evolution 144(3): 281-287, doi: 10.5091/plecevo.2011.487
Negative effects of forest fragmentation and proximity to edges on pollination and herbivory of Bomarea salsilla (Alstroemeriaceae)
expand article infoCarlos E. Valdivia, Alejandra Bahamondez, Javier A. Simonetti
Open Access
Abstract
Background – Habitat fragmentation may have detrimental effects on both plant-mutualistic (i.e.pollination) and plant-antagonistic interactions (i.e.foliar herbivory). Such double negative effects may lead to a change in fitness, because the negative effects of a loss of a mutualism may be counterbalanced by the positive effects of a loss of an antagonism. In spite of being of great importance, however, the assessment of such ecological relationships has traditionally been performed separately. Approach – We evaluated fragmentation and edge effects on floral and foliar display, frequency of pollinator visits, foliar herbivory, and reproductive success, assessed as number of fruits per plant, number of seeds per fruit, and number of seeds per plant, on Bomarea salsilla, a xenogamous vine from southern Chile. Results – Plants occurring at fragments and edges exhibited a smaller floral display and a larger foliar display, and were rarely visited and preyed upon by pollinators and herbivores, respectively. The number of fruits per plant, the number of seeds per fruit, and number of seeds per plant were lower in fragments and at edges than at the core of continuous forest. Although forest fragmentation had a detrimental effect on herbivory, herbivores did not play a modulating role on the lowered pollinator-mediated reproductive success of B. salsilla probably due to the scarcity of foliar attack. Conclusion – Decreased reproductive success of Bomarea salsilla plants due to forest fragmentation and the creation of edge habitats was not counterbalanced by foliar herbivory as expected. The ecological scenario faced by B. salsilla may be a representative phenomenon of numerous other species of the fragmented forests of South America.