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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

Global-Scale Patterns and Trends in Tropospheric NO2 Concentrations, 2005–2018

Nitrogen dioxide (NO2) is an important air pollutant with both environmental and epidemiological effects. The main aim of this study is to analyze spatial patterns and temporal trends in tropospheric NO2 concentrations globally using data from the satellite-based Ozone Monitoring Instrument (OMI). Additional aims are to compare the satellite data with ground-based observations, and to find the tim

A complete time-calibrated multi-gene phylogeny of the european butterflies

With the aim of supporting ecological analyses in butterflies, the third most species-rich superfamily of Lepidoptera, this paper presents the first time-calibrated phylogeny of all 496 extant butterfly species in Europe, including 18 very localised endemics for which no public DNA sequences had been available pre-viously. It is based on a concatenated alignment of the mitochondrial gene COI and u

Temperate insects with narrow seasonal activity periods can be as vulnerable to climate change as tropical insect species

The magnitude and ecological impact of climate change varies with latitude. Several recent models have shown that tropical ectotherms face the greatest risk from warming because they currently experience temperatures much closer to their physiological optimum than temperate taxa. Even a small increase in temperature may thus result in steep fitness declines in tropical species but increased fitnes

The risk of carbon leakage in global climate agreements

Although climate change and international trade are interdependent, policy-makers often address the two topics separately. This may inhibit progress at the intersection of climate change and trade and could present a serious constraint for global climate action. One key risk is carbon leakage through emission outsourcing, i.e. reductions in emissions in countries with rigorous climate policies bei

Food systems and farmers’ behavior during an extreme event: : an analysis of actions and governance following the 2018 drought in Sweden

The extreme weather in terms of drought and heat, which prevailed in Northern Europe during the growing season 2018, had serious consequences for food production and farmers in southern Sweden. Many questions regarding farm production came to a head as drought struck directly against farmers land, economy and wellbeing and hence created vulnerability. This paper analyzes how farmers experienced th

Molecular phylogeny of Sterrhinae moths (Lepidoptera: : Geometridae): towards a global classification

A multigene phylogenetic study was carried out to test current, mostly morphology-based hypotheses on Sterrhinae phylogeny with additional material included from further geographical areas and morphologically different lineages. A maximum likelihood analysis (11 molecular markers and 7665 bp) was conducted on 76 species and 41 genera using iq-tree software. The resulting phylogenetic hypothesis is

Species delimitation and evolutionary relationships among Phoebis New World sulphur butterflies (Lepidoptera, Pieridae, Coliadinae)

The most accepted taxonomic treatment of the New World sulphurs of the genus Phoebis Hübner, [1819] recognizes 16 species including those in the current synonyms Aphrissa and Rhabdodryas. This total conflicts with the results of several recent pierid DNA barcode studies across the Neotropics. We used a five-locus dataset to carry out species delimitation analyses using the coalescence-based method

Soil greenhouse gas emissions under different land-use types in savanna ecosystems of Kenya

Field measurement data on greenhouse gas (GHG) emissions are still scarce for many land-use types in Africa, causing a high level of uncertainty in GHG budgets. To address this gap, we present in situ measurements of carbon dioxide (CO2 ), nitrous oxide (N2 O), and methane (CH4) emissions from the lowlands of southern Kenya. We conducted eight chamber measurement campaigns on gas exchange from fou