L. Petersen

Nature as a nuisance? Ecosystem services and disservices to urban lifestyle

The lifestyle of people living in urban areas has profound direct and indirect impacts on biodiversity. However, the role of urban lifestyle as a driving force of biodiversity change is not very well understood. This is partly because there is a gap between a social science approach focusing on lifestyle and a natural science approach focusing on biodiversity. We propose that the concept of ecological services and disservices is useful in connecting these approaches. Ecosystem services produced by urban green areas are the focus of a wide range of environmental studies, but disservices – such as safety issues in dark parks or pollen causing health problems – have gained only sporadic attention in environmental studies focused on urban ecosystems. We review and discuss different urban ecosystem disservices from a Northern European perspective. We conclude by addressing the key limitations and possibilities of the use of the concept of ecological disservices in urban biodiversity studies.

A fast-scanning, low- and variable-temperature scanning tunneling microscope

The design and performance of a fast-scanning, low- and variable-temperature, scanning tunneling microscope (STM) incorporated in an ultrahigh vacuum system is described. The sample temperature can be varied from 25 to 350 K by cooling the sample using a continuous flow He cryostat and counter heating by a W filament. The sample temperature can be changed tens of degrees on a time scale of minutes, and scanning is possible within minutes after a temperature change. By means of a software implemented active drift compensation the drift rate can be as low as 1 nm/day. The STM is rigid, very compact, and of low weight, and is attached firmly to the sample holder using a bayonet-type socket. Atomic resolution on clean metal surfaces can be achieved in the entire temperature range. The performance of the instrument is further demonstrated by images of adsorbed hexa-tert-butyl-decacyclene molecules on Cu(110), by STM movies, i.e., sequential STM images with a time resolution down to 1 s/image (100×100 A2 with 2...

Changing public discourse on the environment: Danish media coverage of the Rio and Johannesburg UN summits

Abstract Environmental degradation and unsustainable development were addressed on a global scale at the UN summits in Rio de Janeiro in 1992 and Johannesburg in 2002. This contribution presents analyses of Danish television coverage of these two summits and related topics, viewing the media stories as exemplary cases of wider public conceptions of the environment. Over a decade rhetoric about the summits and the environment changed, the agenda changed, and key environmental issues were repackaged. These changes are interpreted in relation to ecological modernisation and discussed as a possible development towards post-environmentalism. Already ecological modernisation can be perceived as post-environmentalist, but the suggestion here is the transformation of ecological modernisation as a prominent discursive frame and thus a further shift in eco-political discourse.

Autonomy and Proximity in Household Heating Practices: the Case of Wood-Burning Stoves

The use of wood-burning stoves as a source of household heating is increasing in Denmark, a development that is leading to considerable levels of particle pollution in residential neighbourhoods. This article reports from a sociological study of wood-burning stove users, the results of which are interpreted in relation to broader discussions regarding social preconditions for integrating environmental considerations into household energy consumption. Wood-burning stove users enjoy a decentralized and also more tangible and visible form of heating supply, one that is not part of wider energy supply systems. Moreover, stove users alter infrastructural conditions in order to pursue personal strategies for domestic heating and comfort, personal strategies that may be rooted in economic considerations or in the desire for homeliness and sensuous pleasure, referring in turn to broader socio-cultural values regarding the ideal home. A de-central and tangible form of heating, with visible environmental impact, does, however, not necessarily lead to integration of environmental concerns into domestic practices for energy consumption.

Imaging the surface Fermi contour on Cu(110) with scanning tunneling microscopy

The Cu(110) surface has two projected bulk band gaps at the edges of the surface Brillouin zone. One of the surface states in these gaps crosses the Fermi level. The corresponding two-dimensional Fermi contour has been imaged using the Fourier transform STM method. By studying the Fourier component intensity distribution, information about the Bloch wave function is extracted.

The Materiality of Everyday Practices in Urban Greenspace

This paper investigates how urban greenspace is integrated in everyday practices of urban populations. What are the social functions that green areas serve, and how do people interact with the materiality of urban greenspace. The paper reports from a recent empirical study in Copenhagen, Denmark, and it seeks to qualify concepts of lifestyle and practice, i.e. concepts by which sociological studies can capture and understand patterns of actions in peoples daily lives. Particularly it seeks to include an understanding of the role of materiality in the analyses of social practices. Inspired by actor-network theory the paper proposes to analyse the role of urban greenspace in everyday practices as actant functions performed by the greenspace and its elements. The question is which roles green areas play in peoples lives and in the community. The study presented in this paper shows that urban green areas are included in everyday life as spaces for free time and household flexibility. They serve a number of different social functions by providing spaces for solitude, for being together and for the experience of civic diversity. And the possibility of having experiences of nature and landscape become an integral part of urban life.

Climate change or variable weather: rethinking Danish homeowners’ perceptions of floods and climate

Climate scenarios predict that an effect of climate change will be more areas at risk of extensive flooding. This article builds on a qualitative case study of homeowners in the flood-prone area of Lolland in Denmark and uses the theories of Tim Ingold and Bruno Latour to rethink the way we understand homeowners’ perception of climate change and local flood risk. Ingold argues that those perceptions are shaped by people’s experiences with and connections to their local landscape. People experience the local variability of the weather, and not global climate change as presented in statistical data and models. This influences the way they understand the future risks of climate change. Concurrently, with the theory of Latour, we can understand how those experiences with the local landscape are mediated by the existing water-managing technologies such as pumps and dikes. These technologies prevent the residents in Lolland from experiencing many of the changes that are already occurring and, at the same time, give them a feeling of being able to control the water to the extent that it is prevented from flooding their homes, both now and in the future. The combination of these two theoretical approaches gives new insights as to why people living in flood-prone areas are not very concerned about climate change.

Dust extinction from Paschen-Balmer lines

We have studied the dust extinction of spiral galaxies by determing the attenuation of the emission from giant extragalactic H II regions. The aim is to push CCD observations as far into the near-IR as possible to compare the near-IR Paschen lines with blue Baimer lines separated by a wide wavelength interval including the corresponding multiplet lines P δ /H e and P γ /H δ , which originate at the same upper atomic level.