265 research outputs found
Ecosystem functioning along gradients of increasing hypoxia and changing soft-sediment community types
Marine ecosystems world-wide are threatened by oxygen deficiency, with potential serious consequences for ecosystem functioning and the goods and services they provide. While the effects of hypoxia on benthic species diversity are well documented, the effects on ecosystem function have only rarely been assessed in real-world settings. To better understand the links between structural changes in macro- and meiofaunal communities, hypoxic stress and benthic ecosystem function (benthic nutrient fluxes, community metabolism), we sampled a total of 11 sites in Haystensfjord and Askerofjord (Swedish west coast) in late summer, coinciding with the largest extent and severity of seasonal hypoxia in the area. The sites spanned oxic to anoxic bottom water, and a corresponding gradient in faunal diversity. Intact sediment cores were incubated to measure fluxes of oxygen and nutrients (NO3-, NO2-, NH4+, PO43-, SiO4) across the sediment-water interface. Sediment profile imaging (SPI) footage was obtained from all sites to assess structural elements and the bioturbadon depth, and additional samples were collected to characterise sediment properties and macro- and meiofaunal community composition. Bottom-water O-2 concentration was the main driver of macrofauna communities, with highest abundance and biomass, as well as variability, at the sites with intermediate O-2 concentration. Meiofauna on the other hand was less sensitive to bottom-water O-2 concentration. Oxygen was the main driver of nutrient fluxes too, but macrofauna as well meiofauna were also significant predictors; DistLM analyses indicated that O-2 concentration, macrofaunal abundance or biomass, and meiofaunal abundance collectively explained 63%, 30% and 28% of the variation in sediment O-2 consumption, NH4+ flux and PO43+ flux, respectively. The study provides a step towards a more realistic understanding of the link between benthic fauna and ecosystem functioning, and the influence of disturbance on this relationship, which is important for management decisions aimed at protecting the dwindling biodiversity in the coastal zones around the world.Peer reviewe
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BioTIME: A database of biodiversity time series for the Anthropocene.
MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL
Outcomes of Brood ParasiteâHost Interactions Mediated by Egg Matching: Common Cuckoos Cuculus canorus versus Fringilla Finches
Antagonistic species often interact via matching of phenotypes, and interactions between brood parasitic common cuckoos (Cuculus canorus) and their hosts constitute classic examples. The outcome of a parasitic event is often determined by the match between host and cuckoo eggs, giving rise to potentially strong associations between fitness and egg phenotype. Yet, empirical efforts aiming to document and understand the resulting evolutionary outcomes are in short supply.We used avian color space models to analyze patterns of egg color variation within and between the cuckoo and two closely related hosts, the nomadic brambling (Fringilla montifringilla) and the site fidelic chaffinch (F. coelebs). We found that there is pronounced opportunity for disruptive selection on brambling egg coloration. The corresponding cuckoo host race has evolved egg colors that maximize fitness in both sympatric and allopatric brambling populations. By contrast, the chaffinch has a more bimodal egg color distribution consistent with the evolutionary direction predicted for the brambling. Whereas the brambling and its cuckoo host race show little geographical variation in their egg color distributions, the chaffinch's distribution becomes increasingly dissimilar to the brambling's distribution towards the core area of the brambling cuckoo host race.High rates of brambling gene flow is likely to cool down coevolutionary hot spots by cancelling out the selection imposed by a patchily distributed cuckoo host race, thereby promoting a matching equilibrium. By contrast, the site fidelic chaffinch is more likely to respond to selection from adapting cuckoos, resulting in a markedly more bimodal egg color distribution. The geographic variation in the chaffinch's egg color distribution could reflect a historical gradient in parasitism pressure. Finally, marked cuckoo egg polymorphisms are unlikely to evolve in these systems unless the hosts evolve even more exquisite egg recognition capabilities than currently possessed
Employer branding : Ett kommunikativt instrument
Det blir allt mer vÀrdefullt för företag att kommunicera ut sitt arbetsgivarvarumÀrke till sina medarbetare och till framtida potentiella medarbetare. Fenomenet benÀmns employer branding och diskuteras i de flesta branscher. Modeindustrin Àr, i detta sammanhang, definitivt inget undantag. Employer branding handlar om att göra ett företag till en attraktiv arbetsplats och erbjuda ett unikt vÀrde till befintliga och framtida medarbetare. Utmaningen inom employer branding framhÀvs genom den omstridda konkurrensen över att finna de mest lÀmpade medarbetarna och behÄlla de rÀtta medarbetarna i kombination med att kommunicera sina unika förmÄner för att tilltala den allt mer specialiserade kompetensen hos arbetssökande. Employer branding kan i mÄnga fall stÄ i relation till sociala medier, som pÄ mÄnga och olika sÀtt kan tilltala den interna sfÀren och externa intressenter hos ett företag. Med detta som grund utvecklades studiens syfte att undersöka hur employer branding skapar en attraktiv arbetsplats genom att öka motivationen hos anstÀllda och förmedla ett externt informationsvÀrde. Studien har utgÄtt frÄn en kvalitativ metod dÀr fyra fallföretag har involverats för att fÄ fram relevant information dÀr semistrukturerade intervjuer genomförts med samtliga fallföretag. Fallföretagens intervjuer presenteras under resultat för att tillsammans kunna mynna ut i en analys. Det har visats att fallföretagen arbetar frÀmst internt med sin employer branding med en levande dialog kring företagets vision och vÀrderingar tillsammans med att erbjuda sina medarbetare utveckling, karriÀrmöjligheter, trivselaktiviteter och se till den enskilde individen. Detta samtidigt som de har blicken mot de externa intressenterna genom att anvÀnda sig av sina befintliga medarbetare och sociala medier för att kommunicera sina unika vÀrden. Dock framförde samtliga fallföretag att de mÄste utveckla sin externa kommunikation sÄ inte en lÀmpad medarbetare gÄr vidare till ett annat företag. Sammantaget visar studien hur fyra olika svenska modeföretag resonerar kring och anvÀnder sig av det allt mer aktuella fenomenet employer branding
Density and fluctuations of a nest-pocket breeding population of the Treecreeper Certhia famililaris over a 28-year period
The number of breeding Treecreeper pairs was estimated from 1982 to 2009 in a 2.7 km2 study area located in south-western Sweden (57\ub039\ub4 N; 12\ub04\ub4 E). Most of the area, which was provided with 205 man-made nest pockets, is covered by broad-leafed forest. The number of first clutches varied between 5 and 21 with an annual average of 14\ub14.2 (SD) breeding pairs (CV 30%). The density of breeding Treecreepers varied from 1.9 to 7.8 pairs/km2 with a mean of 5.1\ub11.86 pairs/km2. The population did not show any statistically significant density trend over the 28 years. The between-year variation in the return rate of ringed adult females that bred after wintering was significantly negatively related to the temperature and precipitation means of the preceding winter. Thus, fewer females returned after milder winters with higher precipitation. The statistical tests pertaining to the variation in the whole breeding population indicate that the species can cope with moderate fluctuations in winter weather, thus preventing significant changes in the number of breeders in the study area
Barns mÄltidsinflytande : - en studie i kring förskolans pedagogiska mÄltid
Abstact Författarnas avgrĂ€nsade syfte med studien Ă€r att undersöka om förskolebarn har nĂ„got existerande inflytande i samband med mĂ„ltidsituationen. Studien ingĂ„r som del i ett uppdrag administrerat av SamhĂ€llsmedicin Ărebro LĂ€ns landsting och FolkhĂ€lsoteamet Norra lĂ€nsdelen, i vilket avsikten Ă€r att göra en genomlysning av all offentlig mĂ„ltid i lĂ€nsdelen. Förmedling av bra matvanor gentemot förskolebarnen ses som allt vĂ€sentligare för att gynna deras hĂ€lsa och vĂ€lbefinnande. HĂ€lsa och vĂ€lbefinnande anses stĂ„ allt mer i fokus mot bakgrund av att fetma och övervikt alarmerande kryper allt lĂ€ngre ner i Ă„ldrarna, varför barns positiva mĂ„ltidsupplevelser i förskolan idag har en viktig roll rent pedagogiskt i ett arbete med folkhĂ€lsoperspektiv. UtifrĂ„n studiens valda omrĂ„de och litteratur stĂ€ller vi vĂ„r forskningsfrĂ„ga: âPĂ„ vilket sĂ€tt existerar barns inflytande i samband med mĂ„ltidssituationen i förskolan?â VĂ„r forskningsfrĂ„ga grundar sig pĂ„ Lpfö 98, med dess mĂ„l och riktlinjer kring normer och vĂ€rden dĂ€r LĂ€roplanen uttrycker dĂ€r att âFörskolan skall aktivt och medvetet pĂ„verka och stimulera barnen att utveckla förstĂ„else för vĂ„rt samhĂ€lles gemensamma demokratiska vĂ€rderingar och att i efterhand omfatta demâ(Lpfö 98 kap 2:1 s. 7). DĂ€r fĂ„r vĂ„r frĂ„ga en ingĂ„ng med ansatsen att tydliggöra barnens möjligheter till demokratisk pĂ„verkan, delaktighet och inflytande i samband mĂ„ltidssituationen i förskolan. VĂ„rt arbete bygger metodologiskt sett, övervĂ€gande pĂ„ en totalstudie i enkĂ€tform, dĂ€r vĂ„r frĂ„gestĂ€llning berör förskolepedagogernas förhĂ„llningssĂ€tt till barnen i samband med mĂ„ltidsituationen. VĂ„ra frĂ„gor avgrĂ€nsas till att gĂ€lla valda perspektiv runt mĂ„ltidsituationen med förskolebarnen. Som komplement till enkĂ€tstudien redogörs för en avgrĂ€nsad intervju med förskolebarn, för att erhĂ„lla ett barnsperspektiv med barns eget perspektiv kring mĂ„ltidsituationen. VĂ„r studies anknytning till mĂ„ltidssituationens olika perspektiv gör den applicerbar till modellen FAMM(Gustafsson I-B 2004), mĂ„ltidens fem aspekter. Slutsats Ă€r att barns inflytande i samband med mĂ„ltidssituationen Ă€r högst begrĂ€nsad dels pĂ„ grund av vuxnas förhĂ„llningssĂ€tt till barn dels pĂ„ grund av rĂ„dande styrsystem utav regelverk och lĂ€roplan. Examensarbetets resultat kommer att anvĂ€ndas av FolkhĂ€lsoteamet i Norra lĂ€nsdelen med flera, för att belysa förbĂ€ttringsomrĂ„den samt föreslĂ„ lokala utvecklingsprojekt kring den offentliga mĂ„ltiden i förskolan
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