5 research outputs found
Fire Promotes Pollinator Visitation: Implications for Ameliorating Declines of Pollination Services
Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, Verbesina alternifolia, as well as a significant difference in floral visitation of V. alternifolia between burn and control treatments. V. alternifolia density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of V. alternifolia was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue.
DOI: 10.1371/journal.pone.007985
Fire Promotes Pollinator Visitation: Implications for Ameliorating Declines of Pollination Services
<div><p>Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, <i>Verbesina alternifolia</i>, as well as a significant difference in floral visitation of <i>V. alternifolia</i> between burn and control treatments. <i>V. alternifolia</i> density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of <i>V. alternifolia</i> was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue.</p> </div
Standardized effects of fire on plant density and pollinator abundance.
<p>(Observation) Plant density and pollinators are positively affected by fire, but the effect diminishes from plants to pollinators. (Experiment) Manipulated and equivalent plant densities between burn and control treatments shows no effect of fire on pollinator abundance. Boxes represent means of standardized z-scores, and values greater than zero indicate a positive effect of fire. Error bars show ± 1 SE and, when non-overlapping with zero, indicate significant differences.</p
Observational and experimental impacts of fire on plant density and floral visitation.
<p>Comparisons from the observation (left panels, A, C, E) and experiment (right panels, B, D, F) show plant density is a mechanism by which fire impacts the abundance of pollinators. Bars represent least square means ± 1 SE. </p