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Lindahl T.,Royal Swedish Academy Of Sciences
Ecological Economics | Year: 2012

The role of environmental uncertainty has not been ignored in the common resource literature, but underlying most of this research is an explicit or implicit assumption of symmetric uncertainty. In this paper I relax the assumption of symmetric uncertainty and analyze how knowledge heterogeneity influences coordination problems that can arise in common resource settings. This paper demonstrates that knowledge heterogeneity can work as a coordination device; the more users differ with respect to knowledge, the smaller is the coordination problem as well as the probability of resource breakdown. Less informed users can take advantage of their ignorance at the expense of more informed users. Furthermore, regulation can reduce the coordination problem further, but only by reinforcing the benefit from ignorance. Thus when analyzing and suggesting policies for reducing the inefficiencies associated with common resources where rivalry prevails, one should not only be concerned about the level of environmental uncertainty, but also the distribution, as it matters too. © 2012 Elsevier B.V..

Hagquist C.,Royal Swedish Academy Of Sciences
Journal of Adolescent Health | Year: 2010

Henriques V.M.J.,Royal Swedish Academy Of Sciences | Henriques V.M.J.,Albanova University Center
Astronomy and Astrophysics | Year: 2012

Context. The wings of the Caii H and K lines provide excellent photospheric temperature diagnostics. At the Swedish 1-m Solar Telescope (SST), the blue wing of Caii H is scanned with a narrowband interference filter mounted on a rotation stage. This provides up to 0\hbox{$\farcs$}10 spatial resolution filtergrams at high cadence that are concurrent with other diagnostics at longer wavelengths. Aims. The aim is to develop observational techniques that provide photospheric temperature stratification at the highest spatial resolution possible and use them to compare simulations and observations at different heights. Methods. We use filtergrams in the Caii H blue wing that were obtained with a tiltable interference filter at the SST. Synthetic observations are produced from three-dimensional (3D) hydro and magneto-hydrodynamic numerical simulations and degraded to match the observations. The temperature structure obtained from applying the method to the synthetic data is compared with the known structure in the simulated atmospheres and with observations of an active region. Cross-correlation techniques using restored non-simultaneous continuum images are used to reduce high-altitude, small-scale seeing signal introduced from the non-simultaneity of the frames when differentiating data. Results. Temperature extraction using high-resolution filtergrams in the Caii H blue wing works reasonably well when tested with simulated 3D atmospheres. The cross-correlation technique successfully compensates for the problem of small-scale seeing differences and provides a measure of the spurious signal from this source in differentiated data. Synthesized data from the simulated atmospheres (including pores) match well the observations morphologically at different observed heights and in vertical temperature gradients. © 2012 ESO.

Callaghan T.V.,Royal Swedish Academy Of Sciences
Philosophical transactions of the Royal Society of London. Series B, Biological sciences | Year: 2013

The subarctic environment of northernmost Sweden has changed over the past century, particularly elements of climate and cryosphere. This paper presents a unique geo-referenced record of environmental and ecosystem observations from the area since 1913. Abiotic changes have been substantial. Vegetation changes include not only increases in growth and range extension but also counterintuitive decreases, and stability: all three possible responses. Changes in species composition within the major plant communities have ranged between almost no changes to almost a 50 per cent increase in the number of species. Changes in plant species abundance also vary with particularly large increases in trees and shrubs (up to 600%). There has been an increase in abundance of aspen and large changes in other plant communities responding to wetland area increases resulting from permafrost thaw. Populations of herbivores have responded to varying management practices and climate regimes, particularly changing snow conditions. While it is difficult to generalize and scale-up the site-specific changes in ecosystems, this very site-specificity, combined with projections of change, is of immediate relevance to local stakeholders who need to adapt to new opportunities and to respond to challenges. Furthermore, the relatively small area and its unique datasets are a microcosm of the complexity of Arctic landscapes in transition that remains to be documented.

Von Heland J.,University of Stockholm | Folke C.,University of Stockholm | Folke C.,Royal Swedish Academy Of Sciences
Global Environmental Change | Year: 2014

We investigate the role of culture in sustaining essential ecosystem services in the arid and erratic climate of an agropastoral landscape in southern Madagascar. Our fieldwork and interviews in Ambovombe subprefecture in Androy addressed land use, agropastoralism, livelihood, institutions and their moral basis. Our analysis points to the interdependence of cultural practices and ecosystem services: sacred forests, crop pollination, subsistence farming, cattle economy and societal transition and purification rituals. We posit a social-ancestral contract that works as a moral attractor structuring and sustaining the agropastoral ecosystem services system. The contract between living and nonliving clan members underpins the cultural practices and rituals that regulate the vulnerable agropastoral system. We conclude that the well-being values of the inhabitants of the south of Madagascar depend upon moralities that lend legitimacy and stability to the management of the social-ecological processes that precondition ecosystem services production. Neither ecosystem nor culture delivers ecosystem services to society. Ecosystem services are generated by an interdependent social-ecological system in which knowledge, practice, and beliefs coevolve: culture is a key factor in their generation and persistence. The study suggests these are significant interdependences to consider in dynamic analyses of ecosystem service production. © 2013 Elsevier Ltd.

Kullander S.,Royal Swedish Academy Of Sciences
Ambio | Year: 2010

Humankind is currently faced with the huge challenge of securing a sustainable energy supply and biofuels constitute one of the major options. However, the commercially traded edible crops are barely sufficient to meet food demand of the present world population. Certain regions, for example EU-27, do not even have a sufficient indigenous crop production. Of this follows that motor biofuels based on edible crops should be avoided. To replace more than some percent of the fossil motor fuels, non-edible biomass-rest products and wastes-should instead be considered for conversion to biofuels. In this way, about 10% of the current fossil fuels can be replaced. Feeding a world population expected to grow by some 50% during the next 50 years will be a major challenge. For environmental reasons it seems that agricultural land cannot be expanded very much, maybe not at all. The solution to the increasing food demand seems therefore to be using the present crop production more efficiently and increasing output from present agricultural land, maintaining biodiversity and climate stability within reasonable limits. In the future, agriculture will need more energy and more water irrigation. Food production is, however, already very energy demanding, requiring several times more externally provided energy than the energy content of the food itself. A sufficient energy supply will be a key issue for the future farming! © 2010 Royal Swedish Academy of Sciences.

Norrby E.,Royal Swedish Academy Of Sciences
Journal of Internal Medicine | Year: 2011

Prions represent a group of proteins with a unique capacity to fold into different conformations. One isoform is rich in beta-pleated sheets and can aggregate into amyloid that may be pathogenic. This abnormal form propagates itself by imposing its confirmation on the homologous normal host cell protein. Pathogenic prions have been shown to cause lethal neurodegenerative diseases in humans and animals. These diseases are sometimes infectious and hence referred to as transmissible spongiform encephalopathies. In the present review, the remarkable evolution of the heterodox prion concept is summarized. The origin of this phenomenon is based on information transfer between homologous proteins, without the involvement of nucleic acid-encoded mechanisms. Historically, kuru and Creutzfeldt-Jakob disease (CJD) were the first infectious prion diseases to be identified in man. It was their relationship to scrapie in sheep and experimental rodents that allowed an unravelling of the particular molecular mechanism that underlie the disease process. Transmission between humans has been documented to have occurred in particular contexts, including ritual cannibalism, iatrogenic transmission because of pituitary gland-derived growth hormone or the use in neurosurgical procedures of dura mater from cadavers, and the temporary use of a prion-contaminated protein-rich feed for cows. The latter caused a major outbreak of bovine spongiform encephalopathy, which spread to man by human consumption of contaminated meat, causing approximately 200 cases of variant CJD. All these epidemics now appear to be over because of measures taken to curtail further spread of prions. Recent studies have shown that the mechanism of protein aggregation may apply to a wider range of diseases in and possibly also outside the brain, some of which are relatively common such as Alzheimer's and Parkinson's diseases. Furthermore, it has become apparent that the phenomenon of prion aggregation may have a wider physiological importance, but a full understanding of this remains to be defined. It may involve maintaining neuronal functions and possibly contributing to the establishment of long-term memory. © 2011 The Association for the Publication of the Journal of Internal Medicine.

Polasky S.,University of Minnesota | Carpenter S.R.,University of Wisconsin - Madison | Folke C.,Royal Swedish Academy Of Sciences | Folke C.,University of Stockholm | Keeler B.,University of Minnesota
Trends in Ecology and Evolution | Year: 2011

Global change issues are complex and the consequences of decisions are often highly uncertain. The large spatial and temporal scales and stakes involved make it important to take account of present and potential consequences in decision-making. Standard approaches to decision-making under uncertainty require information about the likelihood of alternative states, how states and actions combine to form outcomes and the net benefits of different outcomes. For global change issues, however, the set of potential states is often unknown, much less the probabilities, effect of actions or their net benefits. Decision theory, thresholds, scenarios and resilience thinking can expand awareness of the potential states and outcomes, as well as of the probabilities and consequences of outcomes under alternative decisions. © 2011 Elsevier Ltd.

Jansson T.,Royal Swedish Academy Of Sciences
Ecological Economics | Year: 2013

Based on recent research on erosion of ecosystem services, planetary boundaries and predicted pace of urbanization, it is now apparent that humans need to reconnect to the biosphere and that cities in this context, properly managed, could provide great opportunities and arenas for social ecological change and transformation towards sustainability To take advantage of these opportunities one needs to keep in mind that most of the ecosystem services consumed in cities are generated by ecosystems located outside of the cities themselves, not seldom half a world away. In order to operationalize our knowledge, hypothesis and theories on the connections between the work of nature and the welfare and survival of humans over time, we suggest the use of the ecosystem service framework in combination with the merging of the concept "ecology in cities", mainly focusing on designing energy efficient building, sustainable logistics and providing inhabitants with healthy and functioning green urban environments, and the "ecology of cities". The "ecology of cities" framework acknowledges the total dependence of cities on the surrounding landscape and the ever-ongoing dance between urban and rural, viewing the city as an ecosystem. © 2012 Elsevier B.V.

Grant
Agency: GTR | Branch: NERC | Program: | Phase: Research Grant | Award Amount: 290.78K | Year: 2011

Concentrations of greenhouse gases are rising as a result of continued industrial activity with consequences for our future climate. The biosphere has been suggested as a significant factor mitigating atmospheric change, through its capacity to respond to this change by sequestering additional carbon. Key to our understanding and evaluation of these processes is knowledge about the extent to which ecosystems acclimate to elevated CO2. Some research has indicated only short-term growth responses to elevated CO2, but these studies have often focussed on production responses ignoring more subtle shifts in whole ecosystem function. Even where acclimation has occurred, it is important to determine whether any new state of equilibrium results in altered ecosystem function, especially with regard to C loss or gain. Arctic ecosystems are of critical importance to global conservation and store up to one-third of global soil carbon reserves. Their stability under future atmospheric CO2 scenarios will have major influences on global biodiversity and warming. In this study we want to test whether arctic plant communities do not acclimate fully even with extended exposure to elevated CO2, that below-ground responses lag those above-ground and that exposure to elevated CO2 has a cumulative effect on ecosystem properties that influence ecosystem stability, resistance and resilience. As a result of anthropogenic gaseous emissions, the climate of Arctic regions is likely to alter, in particular with regard to temperature and precipitation. These changes, and other periodic perturbations will challenge the stability of current vegetation and soil microbial processes. Sub-arctic heath systems are also subject to periodic mass herbivory events, for example due to mass infestation by the moth Epirrita autumnata. We will therefore investigate field responses (leaf regrowth and soil respiration) to a simulated defoliation event. In a controlled environment facility, we will also investigate whether variations in soil temperature and moisture content will interact with the future capacity of Arctic soils to retain sequestered C under future elevated CO2. The information from this research programme is vital if we are to be able to make effective management decisions based on improved predictions from climate models. Specifically, the extent to which whole ecosystems acclimate to elevated CO2 is a key area of uncertainty in predicting and modelling future scenarios. Research findings will also significantly advance our understanding of the stability of Arctic ecosystems to perturbations under future climate change and important potential impacts on global biodiversity impacts.