16 research outputs found

    Reproductive Ecology and Severe Pollen Limitation in the Polychromic Tundra Plant, Parrya nudicaulis (Brassicaceae)

    Get PDF
    Pollen limitation is predicted to be particularly severe in tundra habitats. Numerous reproductive patterns associated with alpine and arctic species, particularly mechanisms associated with reproductive assurance, are suggested to be driven by high levels of pollen limitation. We studied the reproductive ecology of Parrya nudicaulis, a species with relatively large sexual reproductive investment and a wide range of floral pigmentation, in tundra habitats in interior montane Alaska to estimate the degree of pollen limitation. The plants are self-compatible and strongly protandrous, setting almost no seed in the absence of pollinators. Supplemental hand pollinations within pollinator exclusion cages indicated no cage effect on seed production. Floral visitation rates were low in both years of study and particularly infrequent in 2010. A diversity of insects visited P. nudicaulis, though syrphid and muscid flies composed the majority of all visits. Pollen-ovule ratios and levels of heterozygosity are consistent with a mixed mating system. Pollen limitation was severe; hand pollinations increased seed production per plant five-fold. Seed-to-ovule ratios remained low following hand pollinations, indicating resource limitation is likely to also be responsible for curtailing seed set. We suggest that pollen limitation in P. nudicaulis may be the result of selection favoring an overproduction of ovules as a bet-hedging strategy in this environmental context of highly variable pollen receipt

    Specific ant-pollination in an alpine orchid and the role of floral scent in attracting pollinating ants

    Full text link
    Several studies have recently shown that floral scent can deter ants from flowers. However, when ants serve as reliable pollen vectors, for example in harsh, windy habitats, were flying insects are less active, plants should have evolved floral signals to attract them to the flowers. We tested this hypothesis in the alpine orchid, Chamorchis alpina. C. alpina was found to be predominantly ant pollinated, with some occasional pollination by ichneumonid wasps. In all three investigated populations, only two species of ants, Formica lemani and Leptothorax acervorum visited the flowers and removed pollinaria. These two pollinator ants were found to be among the most common ant species in all habitats, but other, non-pollinating ants were also frequently found, suggesting a factor that mediates specific pollination. Floral morphology was found to be compatible with at least one of the common non-pollinator ants. Floral scent consistently comprised five terpenoid compounds, ÎČ-phellandrene, 1,8-cineole, linalool, α-terpineol, and ÎČ-caryophyllene. A synthetic blend of these five compounds emitting from rubber septa, was found to be attractive to one pollinator ant-species, F. lemani, in the field. The floral scent of C. alpina, through attracting only specific ants, may thus play a role in filtering floral visitors

    Social Acceptability of a Sustainable Forestry Industry in Puerto Rico: Views of Private, Public, and Non-Profit Sectors

    No full text
    Sustainable forestry is key to increase the adaptive capacity and resilience of regions exposed to extreme atmospheric events. Understanding social acceptability of forest management practices through a public dialogue that involves a diversity of stakeholders is important to define management policies and strategies. Here, we inquire about social acceptability of a sustainable forestry industry in Puerto Rico by convening a set of local experts from private, non-profit, and public sectors through focus group discussions. We presented three scenarios characterized by different elements of sustainability. Discussions included organizational and management considerations, potential products and markets, and the impact of extreme weather events. The results show that greater agreement was observed within groups than across groups. Most of the private sector participants valued mainly financial viability, while the public and the non-profit sectors gave more importance to social equity and environmental protection. This suggests that there is no single ideal model; thus, participation from all sectors in subsequent conversations would be worthwhile to seek a model that would work for most of the stakeholders. As a next step, we suggest expanding the stakeholder consultation effort to delineate a clear road map that can inform sustainable forestry planning at the local level

    Social Acceptability of a Sustainable Forestry Industry in Puerto Rico: Views of Private, Public, and Non-Profit Sectors

    No full text
    Sustainable forestry is key to increase the adaptive capacity and resilience of regions exposed to extreme atmospheric events. Understanding social acceptability of forest management practices through a public dialogue that involves a diversity of stakeholders is important to define management policies and strategies. Here, we inquire about social acceptability of a sustainable forestry industry in Puerto Rico by convening a set of local experts from private, non-profit, and public sectors through focus group discussions. We presented three scenarios characterized by different elements of sustainability. Discussions included organizational and management considerations, potential products and markets, and the impact of extreme weather events. The results show that greater agreement was observed within groups than across groups. Most of the private sector participants valued mainly financial viability, while the public and the non-profit sectors gave more importance to social equity and environmental protection. This suggests that there is no single ideal model; thus, participation from all sectors in subsequent conversations would be worthwhile to seek a model that would work for most of the stakeholders. As a next step, we suggest expanding the stakeholder consultation effort to delineate a clear road map that can inform sustainable forestry planning at the local level
    corecore