Search results for "Hall"
showing 10 items of 3177 documents
Epifaunal and infaunal responses to submarine mine tailings in a Norwegian fjord.
2019
Abstract Disposal of mine tailings in marine shallow water ecosystems represents an environmental challenge, and the present paper reports results from a field study in Fraenfjorden, Norway, which is subject to such disposal. Structural and functional responses of benthic infauna and epifauna were investigated along a gradient from heavy tailings deposition to reference conditions. The tailings clearly impacted the faunal composition, with lowered species number close to the outfall. Total abundance of infauna increased in the most impacted area due to dominance of opportunistic species, whereas the epifauna was reduced and represented by a few scattered specimens only. In the most impacted…
Diplurans of subsurface terrestrial habitats in the Iberian Peninsula, with a new species description (Diplura: Campodeidae)
2017
Although Iberian subsurface terrestrial habitats have been sampled for a half century, they remain poorly known. During the last five years much more sampling of these subsurface habitats has been made, mainly in scree slopes (also called colluvial Mesovoid Shallow Substratum habitats, MSS) but also in alluvial debris of temporal watercourses (alluvial MSS). In our study, diplurans, a basal hexapod group, were extracted from two hundred traps installed in 69 locations in the mountain ranges of six different regions of the Iberian Peninsula, from north to south: Cantabrian, Pyrenees, Iberic System, Central System, Prebaetic and Penibaetic Mountains. A total of 1251 specimens in fifteen diplu…
Assessing sampling coverage of species distribution in biodiversity databases
2019
Abstract Aim Biodiversity databases are valuable resources for understanding plant species distributions and dynamics, but they may insufficiently represent the actual geographic distribution and climatic niches of species. Here we propose and test a method to assess sampling coverage of species distribution in biodiversity databases in geographic and climatic space. Location Europe. Methods Using a test selection of 808,794 vegetation plots from the European Vegetation Archive (EVA), we assessed the sampling coverage of 564 European vascular plant species across both their geographic ranges and realized climatic niches. Range maps from the Chorological Database Halle (CDH) were used as bac…
SPACE USE, CIRCADIAN ACTIVITY PATTERN, AND MATING SYSTEM OF THE NOCTURNAL TREE RAT THALLOMYS NIGRICAUDA
2004
We present results of a radiotracking study of the black-tailed tree rat Thallomys nigricauda, based on 3 males and 4 females in the breeding season and 2 males and 5 females in the nonbreeding season. The study was conducted in the southern Kalahari thornveld, South Africa, a savanna landscape of acacia trees and patchy acacia bush. Nocturnal activity patterns, vegetation use, space use, and interactions were followed for 8–17 days. During the breeding season, males were active with 2 synchronous activity peaks shortly after sunset and late at night. Home ranges included the nests of 8–10 females, 6 different daytime resting places, and 3–5 areas of high activity. Males were mobile within …
Habitat- and species-mediated short- and long-term distributional changes in waterbird abundance linked to variation in European winter weather
2019
Aim: Many species are showing distribution shifts in response to environmental change. We explored (a) the effects of inter-annual variation in winter weather conditions on non-breeding distributional abundance of waterbirds exploiting different habitats (deep-water, shallow water, farmland) and (b) the long-term shift in the population centroid of these species and investigate its link to changes in weather conditions. Location: Europe. Methods: We fitted generalized additive mixed Models to a large-scale, 24-year dataset (1990–2013) describing the winter distributional abundance of 25 waterbird species. We calculated the annual and long-term (3-year periods) population centroid of each sp…
Guidelines for risk management in forest planning – what is risk and when is risk management useful?
2018
Managing forest resources occurs under various sources of uncertainty. Depending on the management problem, this uncertainty may have a substantial impact on the quality of the solution. As our knowledge on the sources and magnitude of uncertainty improves, integrating this knowledge into the development of management plans becomes increasingly useful, as additional information can improve the decision-making process. This adjustment requires a fundamental shift in how planning problems are viewed: instead of interpreting risk management as a technique needed only for addressing problems with natural hazards, risk management should be an integral part of most planning problems. Managing ri…
A new tool for the assessment of severe anthropogenic eutrophication in small shallow water bodies
2017
Abstract Unlike in deep stratified lakes, the assessment of eutrophication in shallow aquatic systems (i.e., wetlands, marshes, ponds) should be based on the interaction between water and sediment. The availability of P to primary producers is naturally higher in shallow systems, because the sediment plays an active part via adsorption, precipitation and release processes. Thus, many wetlands in protected areas are naturally eutrophic and have a high trophic status due to intrinsic features and thus, display a high concentration of total-P in the water without necessarily implying pollution or poor quality. We have provided a diagnostic tool based on the chemical equilibrium of dissolved re…
Does air pollution influence the success of species translocation? Trace elements, ultrastructure and photosynthetic performances in transplants of a…
2020
Abstract Species translocation can be considered as a primary conservation strategy with reference to in situ conservation. In the case of lichens, translocations often risk to fail due stress factors associated with unsuitable receptor sites. Considering the bioecological characteristics of lichens, air pollution is among the most limiting stress factors. In this study, the forest macrolichen Lobaria pulmonaria was used as a model to test the hypothesis that the translocation of sensitive lichens is effective only in unpolluted environments. At purpose, 500 fragments or whole thalli were translocated in selected beech forests of Central Europe (the Western Carpathians, Slovakia) where the …
Halloysite nanotubes as a carrier of cornelian cherry (Cornus mas L.) bioactives
2020
Abstract Cornelian cherry fruit extract rich in anthocyanins and iridoids was encapsulated in the halloysite nanotubes in order to obtain a stable nanoscale system for better delivery and prolonged release of bioactive constituents. The cyclic vacuum technique was used for halloysite nanotubes-cornelian cherry composite preparation and the loading of 8.5 wt% was achieved. Pure cornelian cherry extract exhibited antiproliferative effect on HT-29, MCF7, and MRC-5 cells, pristine halloysite nanotubes affected the growth of MCF7 cells, while halloysite nanotubes-cornelian cherry composites demonstrated proliferative activity in all tested cells. The sustained release of anthocyanins was achieve…
Phytoplankton assemblages respond differently to climate warming and eutrophication : A case study from Pyhäjärvi and Taihu
2016
Abstract Long-term monitoring data from two lakes located at different latitudes were used to test the hypothesis that phytoplankton communities respond differently to environmental changes (e.g., global warming and anthropogenic activities, mainly eutrophication). Lake Pyhajarvi (temperate area) and Lake Taihu (subtropical area) are both shallow and productive lakes. Presence/absence data indicated that phytoplankton taxa present did not change significantly in the two lakes over the last two decades. However, biomass data showed that dominance relationships of species changed in both lakes. Results of assemblage ordination indicated that climate change played a vital role in mediating phy…