Search results for "conservation."
showing 10 items of 1994 documents
Spectrofluorimetric study of dissolved organic matter in River Salaca (Latvia) basin waters
2012
Dissolved organic matter (DOM) in surface waters influences mineral weathering, nutrient cycling, aggregation of particulate matter and photochemical reactions in waters and aquatic communities. In this study, the effectiveness of UV and fluorescence measurements in distinguishing the origin of DOM and processes within the river basin were analyzed using the River Salaca basin as an example. The basin of River Salaca is characterized by low anthropogenic pressure, however, the water color during the last few decades has increased (an effect known as brownification). As tools to study the composition of dissolved organic substances in waters of the River Salaca and its tributaries the use of…
Invasive crayfish increase habitat connectivity: a case study in a large boreal lake
2013
Several studies have shown that distinct compartments of lake ecosystems are coupled via transportation of organic matter, nutrients and energy across habitat boundaries. Here we evaluate the potential of the invasive signal crayfish (Pacifastacus leniusculus (Dana)) to modify energy pathways in large boreal lakes. Using a stable isotope mixing model and calculation of the isotopic niches we estimated the contribution of different food sources to the diets of crayfish captured from different habitats, and from that inferred their potential to transport energy across the littoral-profundal gradient. The crayfish caught from the littoral area utilized mainly littoral food sources, whereas the…
Investigating occupational well-being and leadership from a person-centred longitudinal approach: congruence of well-being and perceived leadership
2015
The overall objective of this longitudinal study was to investigate the association between perceived leadership and employee well-being from a person-centred approach utilizing the principles of the conservation of resources theory (Hobfoll, S. E. (1989). Conservation of resources: A new attempt at conceptualizing stress. American Psychologist, 44, 513–524; Hobfoll, S. E. (2002). Social and psychological resources and adaptation. Review of General Psychology, 6, 307–324). First, we aimed to identify latent classes (i.e., subgroups) of employees that demonstrated similar mean levels of stability and change in occupational well-being (i.e., vigour and emotional exhaustion) across a mean time…
Long-term profiles of work-related rumination associated with leadership, job demands, and exhaustion : A three-wave study
2017
ABSTRACTThis study extends previous research on recovery from work stress by investigating the role of qualitative job demands and leadership in employees’ work-related rumination (WRR). The long-term development of WRR was examined from a person-centred approach across 22 months. Drawing on the stressor-detachment framework and conservation of resources theory, we investigated whether different WRR profiles could be understood in terms of levels of and changes in quantitative, cognitive, and emotional job demands, several aspects of supervisory leadership, and exhaustion that was expected to result from the impeded energy restoration process. A three-wave questionnaire study was conducted …
Terrestrial Inputs Drive Seasonality in Organic Matter and Nutrient Biogeochemistry in a High Arctic Fjord System (Isfjorden, Svalbard)
2020
Climate-change driven increases in temperature and precipitation are leading to increased discharge of freshwater and terrestrial material to Arctic coastal ecosystems. These inputs bring sediments, nutrients and organic matter (OM) across the land-ocean interface with a range of implications for coastal ecosystems and biogeochemical cycling. To investigate responses to terrestrial inputs, physicochemical conditions were characterized in a river- and glacier-influenced Arctic fjord system (Isfjorden, Svalbard) from May to August in 2018 and 2019. Our observations revealed a pervasive freshwater footprint in the inner fjord arms, the geochemical properties of which varied spatially and seaso…
Red-list of Italian bryophytes. 1. Liverworts and hornworts
2023
The objective of this study is to provide an updated conservation status of all liverworts and hornworts in the Italian territory, evaluated according to IUCN's Guidelines for Application of IUCN Red List Criteria at Regional Level. Overall, 27.4% of taxa assessed in this study are assigned to a risk category and, therefore, considered threatened in Italy. Four liverworts are considered as Extinct, two liverworts and one hornwort Possibly Extinct at regional level. Moreover, a further 9.8% are assessed as Near Threatened, 10.8% as Data Deficient and 49.7% as Least Concern. Most threats are co-occurring, indicating that many taxa are subjected to a set of correlated adverse processes. The ma…
National high-resolution conservation prioritisation of boreal forests
2023
The continuous decline of forest biodiversity highlights the importance of the development of cost-effective and ecologically sustainable land-use planning approaches. Spatial conservation prioritisation (SCP) can be regarded as a useful tool for this challenge. We produced high-resolution, national scale SCP analyses to identify unprotected forest areas that host valuable forest biodiversity. We used stand-based modelled dead wood potential (DWP) data as a primary surrogate for conservation value. In addition, data on forestry operations that have negative impacts on biodiversity, connectivity between forest areas, the observations of red-listed forest species, connectivity to forest habit…
Macroalgal responses to ocean acidification depend on nutrient and light levels
2015
Ocean acidification may benefit algae that are able to capitalize on increased carbon availability for photosynthesis, but it is expected to have adverse effects on calcified algae through dissolution. Shifts in dominance between primary producers will have knock-on effects on marine ecosystems and will likely vary regionally, depending on factors such as irradiance (light vs. shade) and nutrient levels (oligotrophic vs. eutrophic). Thus experiments are needed to evaluate interactive effects of combined stressors in the field. In this study, we investigated the physiological responses of macroalgae near a CO2 seep in oligotrophic waters off Vulcano (Italy). The algae were incubated in situ …
Predicting valuable forest habitats using an indicator species for biodiversity
2020
Intensive management of boreal forests impairs forest biodiversity and species of old-growth forest. Effective measures to support biodiversity require detection of locations valuable for conservation. We applied species distribution models (SDMs) to a species of mature forest, the northern goshawk (Accipiter gentilis, goshawk), that is often associated with hotspots of forest biodiversity. We located optimal sites for the goshawk on a landscape scale, assessed their state under intensified logging operations and identified characteristics of goshawks' nesting sites in boreal forests. Optimal sites for the goshawk covered only 3.4% of the boreal landscape and were mostly located outside pro…
Comparison of methods to model species habitat networks for decision-making in nature conservation : the case of the wildcat in southern Belgium
2020
Facing the loss of biodiversity caused by landscape fragmentation, implementation of ecological networks to connect habitats is an important biodiversity conservation issue. It is necessary to develop easily reproducible methods to identify and prioritize actions to maintain or restore ecological corridors. To date, several competing methods are used with recurrent debate on which is best and if expert-based approaches can replace data-driven models. We compared three methods: knowledge-driven (expert based), data-driven (based on species distribution model), and a mixed approach. We quantified their differences in habitat and corridor mapping, and prioritizations of landscape elements in t…