2015. január 20., kedd

Kelemen et al. (2015) Ecological Complexity

András Kelemen, Péter Török, Orsolya Valkó, Balázs Deák, Katalin Tóth, Béla Tóthmérész (2015): Both facilitation and limiting similarity shape the species coexistence in dry alkali grasslands. Ecological Complexity 21: 34–38. doi:10.1016/j.ecocom.2014.11.004

Facilitation is an important driver of community assembly, and often overwhelms the effect of competition in stressed habitats. Thus, net effect of biotic interactions is often positive in stressed grasslands, where dominant species and litter can protect the subordinate species. Besides facilitation, niche partitioning can also support species coexistence leading to limiting similarity between subordinate species. Our aim was to provide a detailed analysis of fine-scale biotic interactions in stressed alkali grasslands. We supposed, that there are positive relationships between the main biomass fractions and species richness. We expected the expansion of trait ranges and the increase of trait dissimilarity with increasing biomass scores (total litter, green biomass of dominant species) and species richness. We studied the relationships between main biomass fractions, species richness, functional diversity and functional trait indices (ranges, weighted means and Rao indices). We used fine-scale biomass sampling in nine stands of dry alkali grasslands dominated by Festuca pseudovina. The detected relationships were always positive between the main biomass fractions (green biomass of dominant species, total litter and green biomass of subordinate species) and species richness. We found that the green biomass of dominant species and total litter increased ranges and dissimilarity of functional traits. Our results suggest that in dry alkali grasslands facilitation is crucial in shaping vegetation composition. The green biomass of dominant species and total litter increased the biomass production of subordinate species leading to overyielding. We found that mechanisms of facilitation and limiting similarity were jointly shaping the species coexistence in stressed grasslands, such as alkali grasslands.

  • We proposed a model of fine-scale biotic interactions in stressed alkali grasslands.
  • Trait-based analyses are used to reflect fine-scale species co-existence patterns.
  • Diversity and biomass of subordinate species increased by Festuca biomass and litter.
  • Festuca increased the ranges and dissimilarity of functional traits.
  • Facilitation and limiting similarity jointly shape species coexistence.

Abiotic stress, Biomass, Competition, Functional diversity, Plant traits, Trait dissimilarity

Sutcliffe et al. (2014) Diversity & Distributions

Sutcliffe, L. M. E., Batáry, P., Kormann, U., Báldi, A., Dicks, L. V., Herzon, I., Kleijn, D., Tryjanowski, P., Apostolova, I., Arlettaz, R., Aunins, A., Aviron, S., Baležentienė, L., Fischer, C., Halada, L., Hartel, T., Helm, A., Hristov, I., Jelaska, S. D., Kaligarič, M., Kamp, J., Klimek, S., Koorberg, P., Kostiuková, J., Kovács-Hostyánszki, A., Kuemmerle, T., Leuschner, C., Lindborg, R., Loos, J., Maccherini, S., Marja, R., Máthé, O., Paulini, I., Proença, V., Rey-Benayas, J., Sans, F. X., Seifert, C., Stalenga, J., Timaeus, J., Török, P., van Swaay, C., Viik, E., Tscharntke, T. (2014), Harnessing the biodiversity value of Central and Eastern European farmland. Diversity and Distributions. doi: 10.1111/ddi.12288

A large proportion of European biodiversity today depends on habitat provided by low-intensity farming practices, yet this resource is declining as European agriculture intensifies. Within the European Union, particularly the central and eastern new member states have retained relatively large areas of species-rich farmland, but despite increased investment in nature conservation here in recent years, farmland biodiversity trends appear to be worsening. Although the high biodiversity value of Central and Eastern European farmland has long been reported, the amount of research in the international literature focused on farmland biodiversity in this region remains comparatively tiny, and measures within the EU Common Agricultural Policy are relatively poorly adapted to support it. In this opinion study, we argue that, 10 years after the accession of the first eastern EU new member states, the continued under-representation of the low-intensity farmland in Central and Eastern Europe in the international literature and EU policy is impeding the development of sound, evidence-based conservation interventions. The biodiversity benefits for Europe of existing low-intensity farmland, particularly in the central and eastern states, should be harnessed before they are lost. Instead of waiting for species-rich farmland to further decline, targeted research and monitoring to create locally appropriate conservation strategies for these habitats is needed now.

Agricultural intensification, agri-environment schemes, common agricultural policy, European Union, high nature value farmland