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Organic farming at local and landscape scales benefits plant diversity

Agri-environment schemes (AES) have been suggested to counter negative effects of agricultural intensification and enhance farmland biodiversity, but evaluations have produced inconsistent results. We suggest that this is partly a consequence of scale-dependence, i.e. that the consequence of organic farming will differ depending on the scale of uptake in a particular landscape. To test our hypothe

Modelling natural disturbances in forest ecosystems: a review

Natural disturbances play a key role in ecosystem dynamics and are important factors for sustainable forest ecosystem management. Quantitative models are frequently employed to tackle the complexities associated with disturbance processes. Here we review the wide variety of approaches to modelling natural disturbances in forest ecosystems, addressing the full spectrum of disturbance modelling from

Methane exchange in a boreal forest estimated by gradient method

Forests are generally considered to be net sinks of atmospheric methane (CH4) because of oxidation by methanotrophic bacteria in well-aerated forests soils. However, emissions from wet forest soils, and sometimes canopy fluxes, are often neglected when quantifying the CH4 budget of a forest. We used a modified Bowen ratio method and combined eddy covariance and gradient methods to estimate net CH4

Increased concentrations of nitrate in forest soil water after windthrow in southern Sweden

In January 2005, south-west Sweden was hit by a severe storm that caused large damage to the forests through massive windthrow. The aim of this study was to assess the effect of this windthrow on nitrate concentrations in the soil water below the root zone on 33 forest monitoring plots within the Swedish Throughfall Monitoring Network (SWETHRO). These sites were damaged to different extents by the

Unifying European Biodiversity Informatics (Bio Unify)

In order to preserve the variety of life on Earth, we must understand it better. Biodiversity research is at a pivotal point with research projects generating data at an ever increasing rate. Structuring, aggregating, linking and processing these data in a meaningful way is a major challenge. The systematic application of information management and engineering technologies in the study of biodiver

Salt effects on the soil microbial decomposer community and their role in organic carbon cycling: A review

Salinization of soil is recognised as one of the most pressing environmental challenges to resolve for the next century. We here conduct a synoptic review of the available research on how salt affects decomposer microbial communities and carbon (C) cycling in soil. After summarizing known physiological responses of microorganisms to salinity, we provide a brief overview and qualification of a sele

Nutrient dynamics, microbial growth and weed emergence in biochar amended soil are influenced by time since application and reapplication rate

Evidence suggests that in addition to sequestering carbon (C), biochar amendment can increase crop yields, improve soil quality and nutrient cycling, reduce the leaching of nutrients from soil and stimulate soil microbial activity. However, biochar application primarily benefits soils of intrinsic poor quality, thus the advantages of adding biochar to temperate agricultural soils remains controver

Using the concentration-dependence of respiration arising from glucose addition to estimate in situ concentrations of labile carbon in grassland soil

In this study, we first determined the low molecular weight dissolved organic carbon (LMW DOC) concentration-dependent kinetics of soil respiration in a temperate grassland soil sampled on successive occasions. We then used the established relationship to estimate in situ LMW DOC concentrations from basal respiration measurements. C-14-labelled glucose was used as a model substrate and was added t

Declines amongst breeding Eider Somateria mollissima numbers in the Baltic/Wadden Sea flyway

We report on the status of the Baltic/Wadden Sea flyway Eider population based on trends in breeding and wintering numbers throughout the region, supplemented by changes in the sex ratio and proportion of young Eiders as monitored in the Danish hunting bag. At the flyway scale, total numbers of breeding pairs decreased by 48% during 2000-2009, after relatively stable breeding numbers in 1991-2000.

Delivery of crop pollination services is an insufficient argument for wild pollinator conservation.

There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is

Roots and Associated Fungi Drive Long-Term Carbon Sequestration in Boreal Forest

Boreal forest soils function as a terrestrial net sink in the global carbon cycle. The prevailing dogma has focused on aboveground plant litter as a principal source of soil organic matter. Using C-14 bomb-carbon modeling, we show that 50 to 70% of stored carbon in a chronosequence of boreal forested islands derives from roots and root-associated microorganisms. Fungal biomarkers indicate impaired

A new invasive insect in Sweden -Physokermes inopinatus - tracing forest damage with satellite based remote sensing.

Forests are important from many perspectives. Forestry delivers products such as timber, fiber and fuel; forests are also important for recreational activities as well as for the global carbon balance. Consequently, it is important to develop methods that enable efficient monitoring of disturbances, such as insect attacks, over vast forested areas. These methods can be based on remote sensing, sin

Plant species from mesotrophic wetlands cause relatively high methane emissions from peat soil

Plants can influence methane emissions from wetland ecosystems by altering its production, consumption and transport in the soil. The aim of this study was to investigate how eight vascular plant species from mesotrophic to eutrophic wetlands vary in their influence on CH4 emissions from peat cores, under low and high N supply. Additionally, we measured the production of low-molecular-weight organ

Bioavailable phosphorus in humic headwater streams in boreal Sweden

Bioavailable phosphorus (BAP) concentrations were determined nine times between April and October 2010 in two humic boreal headwater streams draining forest-and mire-dominated catchments. BAP was analyzed in a bioassay in which natural P-limited bacterioplankton grew with natural P as the sole P source. In both streams, approximately 90% of the BAP occurred as dissolved species (passing a 0.2-mu m

Rapid responses of permafrost and vegetation to experimentally increased snow cover in sub-arctic Sweden

Increased snow depth already observed, and that predicted for the future are of critical importance to many geophysical and biological processes as well as human activities. The future characteristics of sub-arctic landscapes where permafrost is particularly vulnerable will depend on complex interactions between snow cover, vegetation and permafrost. An experimental manipulation was, therefore, se

Growth of saprotrophic fungi and bacteria in soil.

Bacterial and fungal growth rate measurements are sensitive variables to detect changes in environmental conditions. However, while methods to assess the species composition and biomass of fungi and bacteria has made much progress, information about growth rates remains surprisingly rudimentary. We review the recent history of approaches to assess bacterial and fungal growth rates, leading up to c

Bird population trends are linearly affected by climate change along species thermal ranges

Beyond the effects of temperature increase on local population trends and on species distribution shifts, how populations of a given species are affected by climate change along a species range is still unclear. We tested whether and how species responses to climate change are related to the populations locations within the species thermal range. We compared the average 20 year growth rates of 62

Land use intensity and landscape complexity-Analysis of landscape characteristics in an agricultural region in Southern Sweden

It is generally recognised that agricultural intensification has lead to simplification of landscape structure, but it has not been clarified if this is a ubiquitous relationship. That is, it has been an open question whether agricultural intensity and landscape simplicity should be regarded as one single or as two separate dimensions. To evaluate this we analysed landscape data in 136 different 1

The Full Annual Carbon Balance of Boreal Forests Is Highly Sensitive to Precipitation

The boreal forest carbon balance is predicted to be particularly sensitive to climate change. Carbon balance estimates of these biomes stem mainly from eddy-covariance measurements of net ecosystem exchange (NEE). However, a full net ecosystem carbon balance (NECB) must include the lateral carbon export (LCE) through discharge. We show that annual LCE at a boreal forest site ranged from 4 to 28%,