Search results for "SCA"
showing 10 items of 23299 documents
Inter-specific nest re-use by Barn Swallows Hirundo rustica
2017
ABSTRACTCapsule: Reports of inter-specific nest re-use by Barn Swallows Hirundo rustica in Europe and North America are reviewed. Inter-specific nest re-use was rare but appeared opportunistic, possibly functioning as a time-saving mechanism or as a result of limited nest sites.
First cases of polygyny for the Bearded Vulture Gypaetus barbatus in the central Pyrenees
2017
ABSTRACTWe report the first cases of polygyny for the Bearded Vulture Gypaetus barbatus in the central Pyrenees, Spain. Although polyandry is frequent in the study area (31.8% of all reproductive units in 2016), we only observed the occurrence of three cases of polygyny over the period 1994–2017. Polygyny in Bearded Vultures is possibly a consequence of habitat saturation.
Echo-sounding can discriminate between fish and macroinvertebrates in fresh water
2008
SUMMARY 1. Acoustic scattering from fish and macroinvertebrates was studied in a boreal Finnish lake at three echosounder frequencies (38, 120 and 200 kHz). Split-beam transducers with partly overlapping 7� beams were employed. Acoustic, fish and invertebrate sampling were undertaken simultaneously. Vertical gradients of temperature and oxygen concentration were measured during the exercise. 2. At all frequencies, a narrow scattering layer coincided with the thermocline. At 38 kHz, fish were detected well with practically no reverberation from invertebrates while 200 kHz detected both fish and invertebrates. 3. Minor differences in the magnitude of acoustic scattering from fish were found b…
Fast pyrolysis of hot-water-extracted and soda-AQ-delignified okra (Abelmoschus esculentus) and miscanthus (miscanthus x giganteus) stalks by Py-GC/MS
2018
Abstract The thermochemical behavior of various samples of okra ( Abelmoschus esculentus ) and miscanthus ( Miscanthus x giganteus ) stalks (initial, hot-water-extracted, and those from sulfur-free delignification) were studied by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). In all cases, major GC-amenable condensable products were measured semi-quantitatively and classified into several product groups. The formation of these product groups from different feedstock samples with varying mass portions of their structural constituents (carbohydrates and lignin) was investigated at 500 °C and 700 °C with a residence time of 5 s and 20 s. The main product groups were aliphatic comp…
Effects of Natura 2000 on nontarget bird and butterfly species based on citizen science data
2020
The European Union's Natura 2000 (N2000) is among the largest international networks of protected areas. One of its aims is to secure the status of a predetermined set of (targeted) bird and butterfly species. However, nontarget species may also benefit from N2000. We evaluated how the terrestrial component of this network affects the abundance of nontargeted, more common bird and butterfly species based on data from long-term volunteer-based monitoring programs in 9602 sites for birds and 2001 sites for butterflies. In almost half of the 155 bird species assessed, and particularly among woodland specialists, abundance increased (slope estimates ranged from 0.101 [SD 0.042] to 3.51 [SD 1.30…
Evaluation of the shielding in a treatment room with an electronic brachytherapy unit.
2017
Esteya® (Elekta Brachytherapy, Veenendaal, The Netherlands) is an electronic brachytherapy (eBT) system based on a 69.5 kVp x-ray source and a set of collimators of 1 to 3 cm in diameter, used for treating non-melanoma skin cancer lesions. This study aims to estimate room shielding requirements for this unit. The non-primary (scattered and leakage) ambient dose equivalent rates were measured with a Berthold LB-133 monitor (Berthold Technologies, Bad Wildbad, Germany). The latter ranges from 17 mSv h-1 at 0.25 m distance from the x-ray source to 0.1 mSv h-1 at 2.5 m. The necessary room shielding was then estimated following US and some European guidelines. The room shielding for all barriers…
Contrasting Patterns in Chironomid (Chironomidae) Communities of Shallow and Deep Boreal Lakes Since the 1960s
2016
Chironomids have been widely used as indicators of trophic conditions of lakes due to their species-specific environmental requirements. In order to understand resilience and deterioration of aquatic ecosystems due to increases and/or decreases in external loading, recent chironomid community and water chemistry data of seven southern Finnish lakes with varying anthropogenic pressures and bathymetric properties were compared with similar data from the 1960s. Altogether 64 taxa were found. At present, the most numerous taxa are Procladius spp., Chironomus f.l. plumosus, Chironomus f.l. salinarius, Stictochironomus f.l. psammophilus, Benthalia spp., Tanytarsus spp. and Cladotanytarsus. In fou…
Cost-efficient strategies to preserve dead wood-dependent species in a managed forest landscape
2016
Negative consequences of intensive forest management on biodiversity are often mitigated by setting aside old forest, but alternative strategies have been suggested. We have compared using simulations the consequences of two of these alternatives setting aside young forests or extending rotation periods - to that of current practice in managed boreal forest In all scenarios we applied a constant conservation budget and predicted forest development and harvesting over 200 years. As a proxy for biodiversity conservation, we projected the extinction risk of a dead wood-dependent beetle, Diacanthous undulatus, in a 50 km(2) landscape in central Sweden, using a colonization-extinction model. Dur…
Land-use and climate related drivers of change in the reindeer management system in Finland: geography of perceptions
2021
Drivers of change in the reindeer management system are rather well-known. But when developing the gover-nance to support the traditional livelihoods, it is crucial to understand also practitioner perceptions. Systematic research on these is lacking. We analyzed the land-use and climate related drivers within the reindeer man-agement area (RMA) in Finland, and, using a perception geography approach, studied the herder perceptions towards these. We conducted an on-site questionnaire survey with herders from 51 herding districts. Factors directly affecting the welfare of reindeer were perceived as crucial by herders, for example basal icing affecting the forage availability, and land-use rela…
Community structure affects trophic ontogeny in a predatory fish.
2016
While most studies have focused on the timing and nature of ontogenetic niche shifts, information is scarce about the effects of community structure on trophic ontogeny of top predators. We investigated how community structure affects ontogenetic niche shifts (i.e., relationships between body length, trophic position, and individual dietary specialization) of a predatory fish, brown trout (Salmo trutta). We used stable isotope and stomach content analyses to test how functional characteristics of lake fish community compositions (competition and prey availability) modulate niche shifts in terms of (i) piscivorous behavior, (ii) trophic position, and (iii) individual dietary specialization. …