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Aim This study investigates inter-annual variability in burnt area in southern Africa and the extent to which climate is responsible for this variation. We compare data from long-term field sites across the region with remotely sensed burnt area data to test whether it is possible to develop a general model. Location Africa south of the equator. Methods Linear mixed effects models were used to det

Natural formation of organically bound chlorine is extensive in many environments. The enzymes associated with the formation of chlorinated organic matter are produced by a large variety of organisms. Little is known about the ecological role of the process, the key question being: why do microorganisms promote chlorination of organic matter? In a recent paper we discuss whether organic matter chl

Evolution of lignocellulose decomposition was one of the most ecologically important innovations in fungi. White rot fungi in the Agaricomycetes (mushrooms and relatives) are the most effective microorganisms in degrading both cellulose and lignin components of woody plant cell walls (PCW). However, the precise evolutionary origins of lignocellulose decomposition are poorly understood, largely bec

Irish peat soils are extensive, covering approximately 14-20% of the national land area. They contain between 53% and 62% of the national soil organic carbon stock. Montane blanket bog covers approximately 25% or 242650ha of the total peatland area in Ireland and is the dominant peatland type covering the upland area of Wicklow. Blanket bogs are very sensitive systems and have experienced much dis

We have developed a habitat selection model based on central place foraging theory. An individual's decision to include a patch in its habitat depends on the marginal fitness contribution of that patch, which is characterized by its quality and distance to the central place. The essence of the model we have developed is a fitness isocline which is a function of patch quality and travel time to the

Proteins contribute to a major part of the organic nitrogen (N) in forest soils. This N is mobilized and becomes available to trees as a result of the depolymerizing activities of symbiotic ectomycorrhizal fungi. The mechanisms by which these fungi depolymerize proteins and assimilate the released N are poorly characterized. Biochemical analysis and transcriptome profiling were performed to examin

AimTo project the potential European distribution of seven broad habitat categories (needle-leaved, broad-leaved, mixed and mediterranean forest, urban, grassland and cropland) in order to assess effects of land use, climate change and increase in CO2 on predicted habitat changes up to the year 2050. LocationEurope. MethodWe modelled the response of European vegetation to changes in land use, clim

Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Am

Monitoring evapotranspiration over land is highly dependent on the surface state and vegetation dynamics. Data from spaceborn platforms are desirable to complement estimations from land surface models. The success of daily evapotranspiration monitoring at continental scale relies on the availability, quality and continuity of such data. The biophysical variables derived from SEVIRI on board the ge

The Dahra field site in Senegal, West Africa, was established in 2002 to monitor ecosystem properties of semiarid savanna grassland and their responses to climatic and environmental change. This article describes the environment and the ecosystem properties of the site using a unique set of in situ data. The studied variables include hydroclimatic variables, species composition, albedo, normalized

Plant canopies affect the canopy micrometeorology, and thereby alter canopy exchange processes. For the simulation of these exchange processes on a regional or global scale, large-scale vegetation models often assume homogeneous environmental conditions within the canopy. In this study, we address the importance of vertical variations in light, temperature, CO2 concentration and humidity within th

Soil nutrient supply is likely to change in the Arctic due to altered process rates associated with climate change. Here, we compare the responses of herbaceous tundra and birch forest understory to fertilization, considering both above-and below-ground responses. We added nitrogen and phosphorus to plots in both vegetation types for three years near Abisko, northern Sweden, and measured the effec

Estimates of relevant source area of pollen (RSAP) and relative pollen productivity (PPE) are critical parameters for quantitative reconstructions of past vegetation and land cover. This study provides estimates for PPE relative to Poaceae for ten taxa, characterizing the cultural landscape of south Estonia and the RSAP for 40 lakes with an average radius of approximately 100 m (22-274 m, average

Nematode-trapping fungi are soil-living fungi that capture and kill nematodes using special hyphal structures called traps. They display a large diversity of trapping mechanisms and differ in their host preferences. To provide insights into the genetic basis for this variation, we compared the transcriptome expressed by three species of nematode-trapping fungi (Arthrobotrys oligospora, Monacrospor

The large bloom-forming flagellate Gonyostomum semen has been hypothesized to be inedible to naturally occurring zooplankton due to its large cell size and ejection of long slimy threads (trichocysts) induced by physical stimulation. In a grazing experiment using radiolabelled algae and zooplankton collected from lakes with recurring blooms of G. semen and lakes that rarely experience blooms, we f

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

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

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

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