Functionality of wet grasslands as green infrastructure

Habitat loss is a global issue that affects land cover patterns, ecological processes and the distribution and abundance of species. As a result, many conservation approaches have appeared, such as the European Union’s green infrastructure (GI) policy and UNESCO’s Biosphere Reserve (BR) concept. Both are being applied in southern Sweden’s Kristianstad Vattenrike Biosphere Reserve (KVBR). Despite concentrated conservation efforts at a local scale to conserve biodiversity, focal grasslands and waders have declined. This calls for the assessment of outputs within the KVBR in terms of both knowledge production and its dissemination, as well as the consequences of management on the ground (Paper I). Focusing on supporting the KVBRs’ work and wader conservation in general, this thesis studied how anthropogenic factors affect the land cover patterns and processes of wet grasslands for waders. Over the past two centuries land use and land cover change have reduced the KVBR’s area of functional grassland habitat by >98% (Paper II). Whilst loss and degradation of wet grassland habitats is considered a primary reason of wader decline in Europe, predator–prey relationships have been proposed as a secondary reason. Using several wet grassland landscapes across Northern Europe, predator-prey relationships were explored (Paper III, IV & V). Firstly, the distribution and abundance of avian predators is determined by resource diversity and anthropogenic factors of a landscape at multiple spatial scales. Secondly, predator abundance and predation pressure were positively correlated, and linked to different wet grassland developmental stages in Northern Europe. Thus, based on the studies contained in this thesis, changes to both land cover patterns and ecological processes play a vital role for the maintenance of wet grasslands as functional GI. Finally, the multiple landscape case study approach employed in this thesis is a novel macroecological tool that encourages knowledge production and learning for functional GI

A combinatorial formula for homogeneous moments

We establish a combinatorial formula for homogeneous moments and give some examples where it can be put to use. An application to the statistical mechanics of interacting gauged vortices is discussed.Comment: 8 pages, LaTe

Effects of Forestry Intensification and Conservation on Green Infrastructures: A Spatio-Temporal Evaluation in Sweden

There is a rivalry between policies on intensification of forest management to meet the demands of a growing bioeconomy, and policies on green infrastructure functionality. Evaluation of the net effects of different policy instruments on real-world outcomes is crucial. First, we present data on final felling rates in wood production landscapes and stand age distribution dynamic in two case study regions, and changes in dead wood amounts in Sweden. Second, the growth of formally protected areas was compiled and changes in functional connectivity analysed in these regions, and the development of dead wood and green tree retention in Sweden was described. The case studies were the counties Dalarna and Jamtland (77,000 km(2)) representing an expanding frontier of boreal forest transformation. In the wood production landscape, official final felling rates averaged 0.84%/year, extending the regional timber frontier. The amount of forest <60 years old increased from 27-34% in 1955 to 60-65% in 2017. The amounts of dead wood, a key forest naturalness indicator, declined from 1994 to 2016 in north Sweden, and increased in the south, albeit both at levels far below evidence-based biodiversity targets. Formal forest protection grew rapidly in the two counties from 1968 to 2020 but reached only 4% of productive forests. From 2000 to 2019, habitat network functionality for old Scots pine declined by 15-41%, and Norway spruce by 15-88%. There were mixed trends for dead wood and tree retention at the stand scale. The net result of the continued transformation of near-natural forest remnants and conservation efforts was negative at the regional and landscape levels, but partly positive at the stand scale. However, at all three scales, habitat amounts were far below critical thresholds for the maintenance of viable populations of species, let alone ecological integrity. Collaboration among stakeholder categories should reject opinionated narratives, and instead rely on evidence-based knowledge about green infrastructure pressures, responses, and states

Macroecology of North European Wet Grassland Landscapes: Habitat Quality, Waders, Avian Predators and Nest Predation

Wet grassland degradation is a global issue that involves both altered land cover patterns and ecological processes, which affect the distribution and abundance of species. The sharp decline in European wader bird (Charadrii) populations is a good example. The aim of this study is to test the hypothesis that the anthropogenic developmental stage of wet grassland habitats and landscapes drives avian nest predator abundance, and thus the predation pressure on nests, which is a major cause of wader bird declines. Using a macroecological approach we selected six wet grassland landscapes representing a gradient in both grassland habitat development and breeding wader population status in four European countries (Belarus, Iceland, Lithuania and Sweden). We (1) mapped wader and avian predator assemblages in multiple wet grassland patches in each landscape, (2) used artificial nests to estimate the relative rate of egg predation, and (3) analyzed relationships between nest predation pressure, corvid nest predators versus raptors, nest loss and the stage of wet grassland habitat and landscape development. We found (1) inverse relationships between the abundance of corvids and waders, as well as between wet grassland developmental stage and waders, and (2) a positive correlation between the probability of nest loss and the density of corvid birds. In conclusion, we found a clear macroecological pattern linking habitat quality, wader populations, nest predators and nest predation. These linkages stress the importance of including nest predation as a factor limiting wader bird populations, and that corvid control or management may be useful management tools

A note on the (1, 1,..., 1) monopole metric

Recently K. Lee, E.J. Weinberg and P. Yi in CU-TP-739, hep-th/9602167, calculated the asymptotic metric on the moduli space of (1, 1, ..., 1) BPS monopoles and conjectured that it was globally exact. I lend support to this conjecture by showing that the metric on the corresponding space of Nahm data is the same as the metric they calculate.Comment: 12 pages, latex, no figures, uses amsmath, amsthm, amsfont

Decompactification of space or time in large N QCD_2

QCD_2 with fundamental quarks on a cylinder is solved to leading order in the 1/N expansion, including the zero mode gluons. As a result of the non-perturbative dynamics of these gauge degrees of freedom, the compact space-time direction gets effectively decompactified. In a thermodynamic interpretation, this implies that there is no pressure of order N and that the chiral condensate of order N is temperature independent. These findings are consistent with confinement of quarks, rule out both chiral and deconfining phase transitions in the finite temperature 't Hooft model, and help to resolve some controversial issues in the literatureComment: Latex2e, 8 pages, no figur