Manipulated structural variability affects the habitat choice of two ground-living beetle species in a laboratory experiment

The habitat choice of two ground-living carabid beetle species (Pterostichus oblongopunctatus (Fabricius) and Carabus hortensis Linneaus) was investigated in a laboratory experiment. Beetles were released in test arenas with two options of manipulated structural variability on the ground, i.e.; bare ground spots versus spots with logging residue (slash). Beetles were studied for 600 seconds and the total time spent on bare ground versus in slash was measured. The results revealed a preference for slash covered ground amongst the investigated beetles. Regardless of species or type of release spot (in the middle of the bare ground or in slash), the carabids resided significantly longer in slash compared with the bare ground. The results support recent studies emphasizing the importance of microhabitat variability for the abundance distribution of arthropods inmanaged systems

Management effect on bird and arthropod interaction in suburban woodlands

<p>Abstract</p> <p>Background</p> <p>Experiments from a range of ecosystems have shown that insectivorous birds are important in controlling the populations of their invertebrate prey. Here, we report on a large field experiment testing the hypothesis that management for enhancing recreational values in suburban woodlands affects the intensity of bird predation on canopy-living arthropods. Bird exclosures were used in two types of management (understory clearance and dense understory) at two foraging heights in oak <it>Quercus robur </it>canopies and the experiment was replicated at two sites.</p> <p>Results</p> <p>The biomass and abundance of arthropods were high on net-enclosed branches but strongly reduced on control branches in both types of management. In woods with dense understory, the effect of bird predation on arthropod abundance was about twice as high as in woods with understory clearance. The effect of bird predation on arthropod biomass was not significantly affected by management.</p> <p>Conclusions</p> <p>Our data provide experimental evidence to support the idea that bird predation on arthropods can be affected by forest management. We suggest that the mechanism is twofold: reduction of bird abundance and shift of foraging behaviour. In urban woodlands, there may be a management trade-off between enhancing recreational values and promoting bird predation rates on arthropods.</p

Biophilia revisited: nature versus nurture

The ‘Biophilia’ hypothesis highlighting humans’ innate, positive response to nature is both increasingly accepted and questioned. Studies support an updated Biophilia. The interplay between inheritance and environment, including culture, governs an individual’s response, from positive to negative. Variety in urban green spaces is needed to optimise benefits to all residents

Insects reared from logging residue on clear-cuts

Coniferous and deciduous logging residue (“slash”) was collected from six 1- year old and six 4-year old clear-cuts in South-West Sweden during the spring of 2002. In the laboratory, insects were emerged under standardised conditions. Insects emerged in 41% of the rearing-tubes with 1-year old slash. In 4-year old slash, 54% of the tubes contained insects. The most successfully emerged order was Coleoptera, represented by 10 families, 22 species and 425 individuals. The second most abundant order was Hymenoptera. The most abundant Coleoptera family was Curculionidae that comprised 48% of all the beetles. Four distinct species groups among Coleoptera were found, each group being separated by slash age and tree category (deciduous/coniferous). Significantly more species were found in the 4-year old deciduous slash, compared to the 1-year old. In coniferous slash, there was a tendency formore species in the 1-year old slash than in the 4-year old. The results suggest that slash is valuable as breeding substrate and/or food supply to the beetle fauna on clear-cuts

Effects of biodiversity and environment-related attitude on perception of urban green space

Green space in cities contributes to the quality of life for city dwellers, e.g., by increasing the opportunity for recreation. However, perception of urban green space is influenced by multiple factors. We investigated effects of biodiversity and environment-related attitudes on visual and auditory perceptions of urban green space. Field measurements of biodiversity were conducted in six sites across an urban gradient in Gothenburg, Sweden, and three categories of biodiversity—high, medium, low—were established. Households were sent a survey on aesthetic perception of urban green space, sound perception and the importance of trees and plants for the perception of bird species. Each respondent focused on the site that was located nearby. The environment-related attitudes comprised “Nature-oriented” and “Urban-oriented” persons and were based on participants’ own attitude estimations. It was shown that participants’ “subjective” aesthetic and sound-related perception of urban greenery were in line with the “objectively” measured subdivisions of high, medium and low biodiversity. So also were their estimations of the importance of trees and plants for perception of bird species in urban greenery, although differing only between high and medium/low biodiversity conditions. Persons rating themselves as highly nature-oriented were shown to give higher scores to urban green space aesthetics and to value greenery-related sounds higher, and to attach greater importance to trees and plants in their perception of bird species in urban greenery, than less nature-oriented persons. Highly urban-oriented persons compared to less urban-oriented persons did the same, but only regarding urban greenery-related aesthetics and sounds of nature. We conclude that environment-related attitudes influence perceptions of green space. Moreover, our findings support the idea that biodiversity per se also influences perceptions; people value green space significantly more with high than with low measured biodiversity. Urban planning needs to provide city inhabitants with green spaces that are species-rich, lush, varied and rich with natural sounds

Reduction of physiological stress by urban green space in a multisensory virtual experiment

Although stress is an increasing global health problem in cities, urban green spaces can provide health benefits. There is, however, a lack of understanding of the link between physiological mechanisms and qualities of urban green spaces. Here, we compare the effects of visual stimuli (360 degree virtual photos of an urban environment, forest, and park) to the effects of congruent olfactory stimuli (nature and city odours) and auditory stimuli (bird songs and noise) on physiological stress recovery. Participants (N = 154) were pseudo-randomised into participating in one of the three environments and subsequently exposed to stress (operationalised by skin conductance levels). The park and forest, but not the urban area, provided significant stress reduction. High pleasantness ratings of the environment were linked to low physiological stress responses for olfactory and to some extent for auditory, but not for visual stimuli. This result indicates that olfactory stimuli may be better at facilitating stress reduction than visual stimuli. Currently, urban planners prioritise visual stimuli when planning open green spaces, but urban planners should also consider multisensory qualities

Norske og svenske blåskjell til Europa: sluttrapport. Geir Olav Knappe (red.)

Prosjektet startet gjennom norsk søknad datert 30. mars 2004 og norsk tilsagn datert 14.11.2005. Prosjektet var planlagt gjennomført i prosjektperioden 01.08.2005 - 31.12.2006. Etter søknad ble prosjektperioden forlenget til 30.06.2007. Denne rapporten inneholder resultatet fra en rekke arbeidsfelt som prosjektmedarbeiderne har vært innom, og hvor noen er obligatoriske i InterReg-sammenheng. Følgende fire elementer i arbeidet som er gjort kommer norsk og svensk skjellnæring til stor nytte framover: 1. En omfattende markedsundersøkelse, i tillegg til to markedsrapporter. Gjennom disse avdekkes det europeiske skjellmarkedet med en detaljrikdom som svært få tidligere har hatt kunnskap om. 2. En økonomisk analyse av norsk skjellnæring som dokumenterer de økonomiske fakta for næringa. 3. På svensk side har prosjektarbeidet munnet ut i en etablering av en produsentorganisasjon (PO), etter europeisk modell innenfor EU. 4. Arbeidet har medført et utstrakt samarbeid mellom aktører på norsk og svensk side. Dette har dannet er et godt grunnlag for videre samarbeid, både innen produksjon og markedsføring og salg av blåskjell på det europeiske markedet. Rapporten er to-delt. Hovedrapporten inneholder en oppsummering og avrapportering av prosjektet.Interreg IIIA, Vattenbrukarnas Riksförbund, Vattenbrukarnas Servicebolag AB, Høgskolen i Nord-Trøndelag, avdeling Namsos, Namdalshagen A

Sounds of Nature in the City: No Evidence of Bird Song Improving Stress Recovery

Noise from city traffic is one of the most significant environmental stressors. Natural soundscapes, such as bird songs, have been suggested to potentially mitigate or mask noise. All previous studies on masking noise use self-evaluation data rather than physiological data. In this study, while respondents (n = 117) watched a 360\ub0 virtual reality (VR) photograph of a park, they were exposed to different soundscapes and mild electrical shocks. The soundscapes-"bird song", "bird song and traffic noise", and "traffic noise"-were played during a 10 min recovery period while their skin conductance levels were assessed as a measure of arousal/stress. No significant difference in stress recovery was found between the soundscapes although a tendency for less stress in "bird song" and more stress in "traffic noise" was noted. All three soundscapes, however, significantly reduced stress. This result could be attributed to the stress-reducing effect of the visual VR environment, to the noise levels being higher than 47 dBA (a level known to make masking ineffective), or to the respondents finding bird songs stressful. Reduction of stress in cities using masking with natural sounds requires further studies with not only larger samples but also sufficient methods to detect potential sex differences

Tractable non-local correlation density functionals for flat surfaces and slabs

A systematic approach for the construction of a density functional for van der Waals interactions that also accounts for saturation effects is described, i.e. one that is applicable at short distances. A very efficient method to calculate the resulting expressions in the case of flat surfaces, a method leading to an order reduction in computational complexity, is presented. Results for the interaction of two parallel jellium slabs are shown to agree with those of a recent RPA calculation (J.F. Dobson and J. Wang, Phys. Rev. Lett. 82, 2123 1999). The method is easy to use; its input consists of the electron density of the system, and we show that it can be successfully approximated by the electron densities of the interacting fragments. Results for the surface correlation energy of jellium compare very well with those of other studies. The correlation-interaction energy between two parallel jellia is calculated for all separations d, and substantial saturation effects are predicted.Comment: 10 pages, 6 figure