Bite forces and evolutionary adaptations to feeding ecology in carnivores

The Carnivora spans the largest ecological and body size diversity of any mammalian order, making it an ideal basis for studies of evolutionary ecology and functional morphology. For animals with different feeding ecologies, it may be expected that bite force represents an important evolutionary adaptation, but studies have been constrained by a lack of bite force data. In this study we present predictions of bite forces for 151 species of extant carnivores, comprising representatives from all eight families and the entire size and ecological spectrum within the order. We show that, when normalized for body size, bite forces differ significantly between the various feeding categories. At opposing extremes and independent of genealogy, consumers of tough fibrous plant material and carnivores preying on large prey both have high bite forces for their size, while bite force adjusted for body mass is low among specialized insectivores. Omnivores and carnivores preying on small prey have more moderate bite forces for their size. These findings indicate that differences in bite force represent important adaptations to and indicators of differing feeding ecologies throughout carnivoran evolution. Our results suggest that the incorporation of bite force data may assist in the construction of more robust evolutionary and palaeontological analyses of feeding ecology.     

Adapting forest health assessments to changing perspectives on threats—a case example from Sweden

A revised Swedish forest health assessment system is presented. The assessment system is composed of several interacting components which target information needs for strategic and operational decision making and accommodate a continuously expanding knowledge base. The main motivation for separating information for strategic and operational decision making is that major damage outbreaks are often scattered throughout the landscape. Generally, large-scale inventories (such as national forest inventories) cannot provide adequate information for mitigation measures. In addition to broad monitoring programs that provide time-series information on known damaging agents and their effects, there is also a need for local and regional inventories adapted to specific damage events. While information for decision making is the major focus of the health assessment system, the system also contributes to expanding the knowledge base of forest conditions. For example, the integrated monitoring programs provide a better understanding of ecological processes linked to forest health. The new health assessment system should be able to respond to the need for quick and reliable information and thus will be an important part of the future monitoring of Swedish forests.     

On the decline of ground lichen forests in the Swedish boreal landscape: Implications for reindeer husbandry and sustainable forest management

Lichens are a bottleneck resource for circumpolar populations of reindeer, and as such, for reindeer husbandry as an indigenous Sami land-use tradition in northern Sweden. This study uses ground lichen data and forest information collected within the Swedish National Forest Inventory since 1953, on the scale of northern Sweden. We found a 71 % decline in the area of lichen-abundant forests over the last 60 years. A decline was observed in all regions and age classes and especially coincided with a decrease of >60 year old, open pine forests, which was the primary explanatory factor in our model. The effects of reindeer numbers were inconclusive in explaining the decrease in lichen-abundant forest. The role that forestry has played in causing this decline can be debated, but forestry can have a significant role in reversing the trend and improving ground lichen conditions.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0759-0) contains supplementary material, which is available to authorized users.     

Land Use and Food Intake of Future Inhabitants: Outlining a Representative Individual of the Most Exposed Group for Dose Assessment

The radiation doses to humans resulting from a potential release of radionuclides from a geological repository for long-lived waste are assessed over tens or even hundreds of thousands of years. Ingestion is expected to be the major exposure pathway, and the group with the highest exposures will be those that consume the most contaminated food. In this paper, we characterize the group of individuals with the highest exposures by considering the physical and biological characteristics of the contaminated area and human requirements for energy and nutrients. We then calculate intake rates based on land-use scenarios drawn from self-sustained communities spanning prehistoric times to an industrial-age agrarian culture. The approach is illustrated by simulating groundwater release of four radionuclides to an expected discharge area. We argue that the derived intake rates may serve as credible bounding cases when projected doses are evaluated for compliance with regulatory criteria.     

Multifaceted Value Profiles of Forest Owner Categories in South Sweden: The River Helge å Catchment as a Case Study

Forest landscapes provide benefits from a wide range of goods, function and intangible values. But what are different forest owner categories’ profiles of economic use and non-use values? This study focuses on the complex forest ownership pattern of the River Helge å catchment including the Kristianstad Vattenrike Biosphere Reserve in southern Sweden. We made 89 telephone interviews with informants representing the four main forest owner categories. Our mapping included consumptive and non-consumptive direct use values, indirect use values, and non-use values such as natural and cultural heritage. While the value profiles of non-industrial forest land owners and municipalities included all value categories, the forest companies focused on wood production, and the Swedish Environmental Protection Agency on nature protection. We discuss the challenges of communicating different forest owners’ economic value profiles among stakeholders, the need for a broader suite of forest management systems, and fora for collaborative planning.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-012-0374-2) contains supplementary material, which is available to authorized users.     

Ecology,evolution, and management strategies of northern pike populations in the Baltic Sea

Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.     

Traditional Farming Landscapes for Sustainable Living in Scandinavia and Japan: Global Revival Through the Satoyama Initiative

Traditional, pre-industrial farming was adapted to the natural environment—topography, geology, hydrology, climate, and biota. Traditional land use systems are still to be traced in Scandinavia as an “infield/outland landscape”, and in Japan as a “Satoyama landscape.” There are obvious similarities and differences in land use—the main difference being that pasturing of cattle and sheep has been less important in Japan. These land use systems can be traced back to early sedentary settlements 1500–2500 years ago. In both regions, traditional management almost ceased in the mid-twentieth century leading to afforestation and decreased biological diversity. Today, there is in Japan a growing movement for landscape restoration and promotion of a sustainable living countryside based on local agrarian and forestry production, local energy, tourism, etc. With this background, the so-called Satoyama Initiative has been organized and introduced as a global socio-ecological project with ecosystem services for human well-being.     

Persistent organic pollutants (POP) in a benthic omnivore--a comparison between lake and stream crayfish populations

We investigated the accumulation of PCB and DDT in crayfish populations in 10 streams in southern Sweden. The results were compared with an earlier study on crayfish in lakes from the same area. We found that the concentration of pollutants in crayfish did not differ between the two types of systems. Variation in body burden was higher in stream living crayfish probably because of the higher influence from pollutants deposited in the catchment area and the more dynamic transport in streams. In streams, p,p'-DDE concentrations were positively correlated to trophic status (total phosphorous) while PCB did not show any correlation with the nutrient regime. Further, mean SigmaPCB and p,p'-DDE concentrations in crayfish did not correlate in streams. We suggest that the sources of the two pollutants differ for stream living crayfish. The results indicate that crayfish in streams are affected to a higher degree to pollutants in the catchment area and the precipitation regime. In lakes, internal processes govern uptake of pollutants in crayfish.     

Sorption of triazoles to soil and iron minerals

Triazoles, additives in runway de-icers, are found in soil and groundwater at airport sites. To better understand the fate and transport of benzotriazole (BTA) and methylbenzotriazole (MeBTA) and to assess possible remediation options of contaminated groundwater, sorption to various soils and ferrous sorbents has been studied. In batch experiments, limited non-linear sorption of BTA to mineral subsoil from the Oslo International Airport, Gardermoen was observed. The sorption to soil could be described using a Freundlich isotherm. pH affected sorption of BTA to subsoil, although the effect was not strong. Increased sorption was observed to zerovalent iron (Fe(0)). MeBTA showed similar sorption behaviour as BTA although the sorption coefficient was generally higher. Sorption to Fe(0) seems to be controlled by multi-layer coverage. Our data suggest that sorption of triazoles to Fe(2)O(3) is negligible. However BTA sorption to 2-line and 6-line ferrihydrites showed strong sorption. The results demonstrate that triazoles are highly mobile in the subsurface environment, however zerovalent iron can be an effective medium for groundwater remediation. Without remediation, wide distribution of triazoles in the environment can be expected due to its extensive application and limited degradability.