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Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mountaintops. Population shifts towards poles and mo

Commercially available fast-response analysers for methane (CH4) and nitrous oxide (N2O) have recently become more sensitive, more robust and easier to operate. This has made their application for long-Term flux measurements with the eddy-covariance method more feasible. Unlike for carbon dioxide (CO2) and water vapour (H2O), there have so far been no guidelines on how to optimise and standardise

Today, more than ever, ‘Spaceship Earth’ is an apt metaphor as we chart the boundaries for a safe planet1. Social scientists both analyse why society courts disaster by approaching or even overstepping these boundaries and try to design suitable policies to avoid these perils. Because the threats of transgressing planetary boundaries are global, long-run, uncertain and interconnected, they must be

Chamber measurements of trace gas fluxes between the land surface and the atmosphere have been conducted for almost a century. Different chamber techniques, including static and dynamic, have been used with varying degrees of success in estimating greenhouse gases (CO2, CH4, N2O) fluxes. However, all of these have certain disadvantages which have either prevented them from providing an adequate es

Background and aims: Plant diversity – ecosystem processes relationships are essential to our understanding of ecosystem functioning. We aimed at disentangling the nature of such relationships in a mesotrophic grassland that was highly heterogeneous with regards to nutrient availability. Methods: Rather than targeting primary productivity, like most existing reports do, we focused our study on bel

The Arctic tundra plays an important role in the carbon cycle as it stores 50% of global soil organic carbon reservoirs. The processes (fluxes) regulating these stocks are predicted to change due to direct and indirect effects of climate change. Understanding the current and future carbon balance calls for a summary of the level of knowledge regarding chamber-derived carbon dioxide (CO2) flux stud

The central role that ectomycorrhizal (EM) symbioses play in the structure and function of boreal forests pivots around the common assumption that carbon (C) and nitrogen (N) are exchanged at rates favorable for plant growth. However, this may not always be the case. It has been hypothesized that the benefits mycorrhizal fungi convey to their host plants strongly depends upon the availability of C

Heavy metals are some of the most persistent and potent anthropogenic environmental contaminants. Although heavy metals may compromise microbial communities and soil fertility, it is challenging to causally link microbial responses to heavy metals due to various confounding factors, including correlated soil physicochemistry or nutrient availability. A solution is to investigate whether tolerance

It is well recognized that organic soil management stimulates bacterial biomass and activity and that including cover crops in the rotation increases soil organic matter (SOM). Yet, to date the relative impact of different cover crop species and organic vs. non-organic soil management on soil bacteria and fungi and on SOM quantity and quality remains to be tested. We used a long-term (10 years) fu

We measured methane fluxes of a patterned bog situated in Siikaneva in southern Finland from six different plant community types in three growing seasons (2012-2014) using the static chamber method with chamber exposure of 35 min. A mixed-effects model was applied to quantify the effect of the controlling factors on the methane flux.The plant community types differed from each other in their water

Extreme climate events and nonsustainable land use are important drivers altering the functioning of European ecosystems, resulting in loss of the services provided. Yet a consensus method for regular continental scale assessment of ecosystem condition in relation to land degradation (LD) is still lacking. Here, we propose a new remote sensing-based approach allowing for improved, repeated assessm

The extent to which ectomycorrhizal (ECM) fungi enable plants to access organic nitrogen (N) bound in soil organic matter (SOM) and transfer this growth-limiting nutrient to their plant host, has important implications for our understanding of plant–fungal interactions, and the cycling and storage of carbon (C) and N in terrestrial ecosystems. Empirical evidence currently supports a range of persp

The relationship between pesticides and pollinators, while attracting no shortage of attention from scientists, regulators, and the public, has proven resistant to scientific synthesis and fractious in matters of policy and public opinion. This is in part because the issue has been approached in a compartmentalized and intradisciplinary way, such that evaluations of organismal pesticide effects re

We present a method for remote sensing based monitoring of changes in dryland ecosystem functioning based on the assumption that an altered vegetation rainfall relationship (VRR) indicates changes in vegetation biophysical processes, potentially leading to changes in ecosystem functioning. We describe the VRR through a linear regression between integrated rainfall and vegetation productivity (usin

Isoprene is a highly reactive volatile organic compound emitted by vegetation, known to be a precursor of secondary organic aerosols and to enhance tropospheric ozone formation under polluted conditions. Isoprene emissions respond strongly to changes in meteorological parameters such as temperature and solar radiation. In addition, the increasing CO2 concentration has a dual effect, as it causes b

In the classical plenary lecture ‘Global limnology’ (J.A. Downing, 2007, SIL in Montréal), a new holistic direction for freshwater science was pointed out, focused at upscaling of limnological processes to planet Earth. Since then, the literature on the global importance of freshwater networks, especially as routes for carbon degassing, burial and transport, has grown explosively. This has been re

In spite of substantial greenhouse gas emissions from photo-degradation of dissolved organic carbon (DOC), little is known about the variability in DOC photo-reactivity. It has been suggested that photo-reactivity depends on the degree of DOC pigmentation. However, recent evidence suggests that also non-colored fractions can be photo-reactive. Furthermore photo-degradation processes interact with

Swedish alpine and subarctic areas undergo rapid transitions due to climate change, especially in relatively humid areas where the forest vegetation is expanding. It has been suggested that lakes in these areas are in transition from clearwater into brownwater state, because of the humus layer building up in surrounding soils, with negative consequences, e.g., for the biomass production of zooplan

The stable carbon isotope ratio (δ13C) is a key tool in tracing the source of carbon within and across ecosystems. In isotope mixing models dissolved organic carbon (DOC) from terrestrial sources is often assigned a fixed δ13C of roughly -28‰ to -27‰ in C3 plant-dominated areas. However, the claim of a uniform δ13C distribution for terrestrial DOC sources of different reactivity has seldom been te