Traditional prescribed burning of coastal heathland provides niches for xerophilous and sun‑loving beetles

In Western Norway, farmers have traditionally used fire as a management tool in coastal heathlands to enhance the fodder quality for livestock. Rotational prescribed burning increases landscape heterogeneity by creating a mosaic of different regeneration stages of heather. Ground beetle (Coleoptera: Carabidae) responses to fire in traditionally managed coastal heathland have already been studied, but less is known about other beetle groups in this system. We compared the beetle activity between patches of mature and recently burnt heath, by looking at diversity indices, species composition and ecological preferences and traits. Contrary to previous studies, we did not find an increase in beta diversity after disturbance, but we found that prescribed burning offers micro-environmental conditions which enhanced the activity of sun-loving and xerophilous species. We also identified new indicator species for both mature and pioneer heath in five beetle families: Carabidae, Staphylinidae, Curculionidae, Leiodidae, and Scirtidae. Rotational prescribed burning was confirmed to be an efficient conservation tool for specialists without affecting the overall diversity of the site. We recommend the use of several taxa, ecological preferences and traits to assess the impact of prescribed burning and to monitor the condition of traditionally managed coastal heathlands.publishedVersio

Directed endozoochorous dispersal by scavengers facilitate sexual reproduction in otherwise clonal plants at cadaver sites

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Just graze it! Biodiversity, nectar and forage resources in cultural landscapes grazed by different livestock species

ABSTRACTThe Nordhordland UNESCO Biosphere Reserve encompasses a heterogeneous landscape which provides numerous ecosystem services. Semi-natural grasslands provide forage for traditionally managed livestock and are important sources of nectar and pollen for pollinators. However, these services are not evenly distributed due to different biotic and abiotic constraints of the fjord landscape, which stretches from flat coastal areas to steep hills and mountains inland. We studied how geographic location and grazing livestock type affect the plant species richness, plant functional group composition, nectar and forage resources of these grasslands. We recorded plant species percentage cover in 30 fields in the Nordhordland Biosphere Reserve grazed by sheep, goats or cattle, and from these data we calculated indicator values for forage and nectar resource using species index values from existing trait databases. Sites grazed by cattle had significantly different plant functional group compositions than sites grazed by sheep or goats, independent of geographical location. Forage resource indicator values were lower at coastal sites grazed by sheep. We found a weak but significant positive correlation between nectar resource indicator value and plant species richness, as well as between nectar and forage resource indicator values. Type of livestock and geographical location are not the only factors influencing provisioning services in semi-natural grasslands. Nonetheless, traditional grazing maintains ecosystem service delivery even in low-productive coastal areas. Forage resource, nectar provision and plant species richness appear to be bundled, providing clear guidance for managing ecosystem services in Nordhordland UNESCO Biosphere Reserve’s valuable cultural landscapes

Directed endozoochorous dispersal by scavengers facilitate sexual reproduction in otherwise clonal plants at cadaver sites

1. The regeneration niche of many plant species involves spatially and tempo -rally unpredictable disturbances, called recruitment windows of opportunity. However, even species with clear dispersal adaptations such as fleshy berries may not successfully reach such elusive regeneration microsites. Ericaceous, berry- producing species in the northern hemisphere demonstrate this dispersal limitation. They are said to display a reproductive paradox owing to their lack of regeneration in apparently suitable microsites despite considerable investmentin producing large quantities of berries.2. Cadavers generate vegetation-denuded and nutrient-rich disturbances termedcadaver decomposition islands (CDIs). Cadavers attract facultative scavengerswith considerable capacity for endozoochorous seed dispersal. We hypoth -esize that CDIs facilitate recruitment in berry- producing ericaceous species due to endozoochorous dispersal directed toward favorable microsites with low competition.3. We examined seedling establishment within a permanent, semi- regular 10× 10 m grid across an ungulate mass die- off on the Hardangervidda plateau in southeastern Norway. Competing models regarding the relative importance of factors governing recruitment were evaluated, specifically cadaver location (elevated seed rain) and microsite conditions (competition).4. We found that CDIs did facilitate seedling establishment, as cadaver density was the best predictor of seedling distribution. Other important factors govern -ing seedling establishment such as percentage cover of soil and vascular plants alone were inadequate to explain seedling establishment.5. Synthesis: This study provides a novel understanding of sexual reproduction in species with cryptic generative reproduction. The directed nature of endozoo-chorous dispersal combined with long- distance dispersal abilities of medium to large vertebrate scavengers toward cadavers allows plants to exploit the advan -tageous but ephemeral resource provided by CDIs.publishedVersio

Complexity within an oil palm monoculture : The effects of habitat variability and rainfall on adult dragonfly (Odonata) communities

Recent expansion of oil palm agriculture has resulted in loss of forest habitat and forest‐dependent species. However, large numbers of species—particularly insects—can persist within plantations. This study focuses on Odonata (dragonflies and damselflies): a charismatic indicator taxon and a potentially valuable pest control agent. We surveyed adult Odonata populations biannually over three years within an industrial oil palm plantation in Sumatra, Indonesia. We assessed the effects of rainfall (including an El Niño Southern Oscillation‐associated drought), the role of roadside ditches, and the importance of understory vegetation on Odonata populations. To assess the impacts of vegetation, we took advantage of a long‐term vegetation management experiment that is part of the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Programme. We found 41 Odonata species, and communities varied between plantation core and roadside edge microhabitats, and between seasons. Abundance was significantly related to rainfall levels four months before surveys, probably indicating the importance of high water levels in roadside ditches for successful larval development. We found no significant effect of the BEFTA understory vegetation treatments on Odonata abundance, and only limited effects on community composition, suggesting that local understory vegetation structure plays a relatively unimportant role in determining communities. Our findings highlight that there are large numbers of Odonata species present within oil palm plantations and suggest that their abundance could potentially be increased by maintaining or establishing waterbodies. As Odonata are predators, this could bring pest control benefits, in addition to enhancing biodiversity within intensive agricultural landscapes