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Functional implications of the pH-trait distribution of the microbial community in a re-inoculation experiment across a pH gradient

We compared the influence of the microbial community composition and the environmental conditions for the functioning - microbial growth and respiration - and trait distribution - bacterial pH tolerance - of soil microorganisms across a pH gradient. Sterilised soil microcosms, including pH 4.1, 5.2, 6.7 and 8.3, with added plant litter were inoculated with unsterilized soil in a factorial design a

The effect of ambient temperature on larvae of Scatopsciara cunicularius (Diptera: Sciaridae) feeding on the thallose liverwort Marchantia polymorpha

Herbivory on liverworts is rarely reported. We studied the effects of feeding by larvae of the sciarid fly Scatopsciara cunicularius on the growth of the thalloid liverwort Marchantia polymorpha at two different constant temperatures, 12°C and 22°C. Larvae reared at the lower temperature fed slower and over a longer period of time, which resulted in more damage and a greater reduction in the growt

The role of institutional innovations in the transition to low-carbon futures

Deep cuts in carbon emissions to avoid dangerous climatic change will require fundamental transformations of the energy and transport systems. This is an enormous challenge for society and the political system. In order to tackle this challenge, we argue that it will be necessary to develop new institutions and institutional practices that address and give priority to long-term climate policy obje

Grazing resistance allows bloom formation and may explain invasion success of Gonyostomum semen

The nuisance alga Gonyostomum semen (Raphidophyceae) has expanded in the Nordic countries during the last decades and can dominate lake phytoplankton communities almost completely. A possible explanation to its dominance could be limited grazing by zooplankton. We investigated the potential grazing pressure on G. semen using an experimental approach supported by field data. We determined the grazi

Patterns of plastid and nuclear variation among apomictic polyploids of Hieracium: evolutionary processes and taxonomic implications.

Background and AimsApomictic species (with asexual seed production) make up for 20-50 % of all taxonomically recognized species in northern Europe, but the phylogenetic relationships of apomictic species and the mode of evolution and speciation remain largely unknown and their taxonomy is consequently disputed.MethodsIn the present study, plastid psbD-trnT sequences (349 accessions) and 12 nuclear

Habitat preferences and conservation of the Marbled Jewel Beetle Poecilonota variolosa (Buprestidae)

Detailed knowledge on habitat requirements is a key to successful conservation actions. The marbled jewel beetle Poecilonota variolosa (Buprestidae) has a wide global distribution but populations are often scarce and typically fragmented. In Sweden it is monophagous on aspen Populus tremula and is classified as near threatened on the Swedish Red List due to its rapid population decline. This study

Great flights by great snipes: long and fast non-stop migration over benign habitats.

Migratory land birds perform extreme endurance flights when crossing ecological barriers, such as deserts, oceans and ice-caps. When travelling over benign areas, birds are expected to migrate by shorter flight steps, since carrying the heavy fuel loads needed for long non-stop flights comes at considerable cost. Here, we show that great snipes Gallinago media made long and fast non-stop flights (

Partial migration in fishes: causes and consequences.

Partial migration, where only some individuals from a population migrate, has been widely reported in a diverse range of animals. In this paper, what is known about the causes and consequences of partial migration in fishes is reviewed. Firstly, the ultimate and proximate drivers of partial migration are reflected upon: what ecological factors can shape the evolution of migratory dimorphism? How i

Glacial clay affects foraging performance in a Patagonian fish and cladoceran

Climate change is altering temperatures and precipitation patterns all over the world. In Patagonia, Argentina, predicted increase in precipitation together with rapidly melting glaciers increase the surface runoff, and thereby the transport of suspended solids to recipient lakes. Suspended solids affect the visual conditions in the water which in turn restricts visual foraging. The native fish Ap

Origin and diversification of the california flora: re-examining classic hypotheses with molecular phylogenies.

The California Floristic Province exhibits one of the richest floras on the planet, with more than 5500 native plant species, approximately 40% of which are endemic. Despite its impressive diversity and the attention it has garnered from ecologists and evolutionary biologists, historical causes of species richness and endemism in California remain poorly understood. Using a phylogenetic analysis o

Regime shifts in shallow lakes: the importance of seasonal fish migration

Shallow eutrophic lakes commonly exist in two alternative stable states: a clear-water state and a turbid water state. A number of mechanisms, including both abiotic and biotic processes, buffer the respective states against changes, whereas other mechanisms likely drive transitions between states. Our earlier research shows that a large proportion of zooplanktivorous fish populations in shallow l

Long-term warming of a subarctic heath decreases soil bacterial community growth but has no effects on its temperature adaptation

We tested whether bacterial communities of subarctic heath soil are adapted to elevated temperature after experimental warming by open-top greenhouses for 7 or 17 years. The long-term warming by 1-2 degrees C significantly decreased bacterial community growth, by 28% and 73% after 7 and 17 years, respectively. The decrease was most likely due to decreased availability of labile substrate under war

Time to establishment success for introduced signal crayfish in Sweden - a statistical evaluation when success is partially known

The signal crayfish Pacifastacus leniusculus is an invasive species in Sweden, threatening the red-listed nobel crayfish Astacus astacus through spreading the crayfish plague. Time-to-event models can handle censored data on such introduced populations for which the state (successful or not) is only partially known at the last observation, but even though data on introduced populations most often

Foraging success of juvenile pike Esox lucius depends on visual conditions and prey pigmentation

Young-of-the-year pike Esox lucius foraging on copepods experienced different foraging success depending on prey pigmentation in water visually degraded by brown colouration or algae. Both attack rate and prey consumption rate were higher for E. lucius foraging on transparent prey in brown water, whereas the opposite was true in algal turbid water. Pigments in copepod prey may have a cryptic funct

Water brownification may increase the invasibility of a submerged non-native macrophyte

Environmental conditions and human activities play a significant role in structuring novel assemblages of native and non-native species. Ongoing and future climatic change may alter the performance of native and non-native species and their biotic interactions. In the northern hemisphere, expected climate changes include warmer temperatures and higher precipitation, the latter of which may increas

High zooplankton diversity in the extreme environments of the McMurdo Dry Valley lakes, Antarctica

The McMurdo Dry Valley lakes of Antarctica constitute some of the harshest and most isolated freshwater environments on Earth which might be expected to limit the biogeographical expansion of many organisms. Despite this, we found that the biodiversity of rotifer zooplankton is the highest ever recorded on the Antarctic mainland. We identified in total nine rotifer taxa, of which six are new to th

Phosphorus addition increased carbon partitioning to autotrophic respiration but not to biomass production in an experiment with Zea mays

Plant carbon (C) partitioning—the relative use of photosynthates for biomass production, respiration, and other plant functions—is a key but poorly understood ecosystem process. In an experiment with Zea mays, with or without arbuscular mycorrhizal fungi (AMF), we investigated the effect of phosphorus (P) fertilization and AMF on plant C partitioning. Based on earlier studies, we expected C partit

Coupled Agricultural Subsidies in the EU Undermine Climate Efforts

Subsidizing polluting industries generally leads to increased pollution locally. However, given the diversity of production technologies across countries and international trade, the global impact of unilateral policies is not a priori clear. We use the agricultural sector model CAPRI to simulate the impact of removing the voluntary coupled support for ruminants, presently permitted under the EU C