Inverted, ’parallel’ accretion of organic material in the cave Setergrotta, Rana, northern Norway: a case study

The occurrence of an upside-down parallel accretion of organic gyttja, about 10 cm in thickness is reported from the ceiling of an overflow passage in Setergrotta cave, Mo-i-Rana, northern Norway. The deposition process depended on seasonal flooding, was 14C dated back to c. 6500 cal. BC (7645 ± 115 BP). Two pollen diagrams are presented, one from the accretion and one of a nearby minerogenic cave floor deposit. In the accretion sequence, pollen of spruce (Picea abies) was found only in the youngest parts and corresponds to what is known from vegetation historical studies in the region. No significant signals of neither of known vegetation changes caused by climate nor human impact are found in the parallel accretion, contrary to the floor deposit. One of them indicates a marked deforestation dated to about 790 cal. BC in the catchment area for the cave pollen/water supply.Key words: Pollen analysis, 14C date, inverted parallel cave accretion.Obrnjene ‘paralelne’ akrecije organskega materiala v Jami Setergotta, Rana, severna Norveška: študijski primerV članku poročamo o obrnjenih, do 10 cm debelih, paralelnih akrecijah organskega sedimenta (gyttja) v prelivnem rovu jame Settergrotta, Moi-i-Rana, severna Norveška. Odlaganje tega sedimenta je bilo vezano na sezonsko poplavljanje rova. 14C datacije so določili največjo starost 6500 cal. BC (7645 ± 115 BP). Primerjamo tudi pelodna diagrama iz akrecije z diagramom minerogenih sedimentov na jamskih tleh. V zaporedju akrecije smo pelode smreke (Picea abies) našli le v najmlajšem delu, kar ustreza ugotovitvam zgodovinskih študij vegetacije v regiji. V akrecijah nismo našli nobenih pomembnih znakov vegetacijskih sprememb, ki bi jih povzročile klimatske spremembe ali človek. Drugače je v minerogenem sedimentu na jamskih tleh, kjer pelodna analiza kaže na deforestacijo v času 790 cal. BC v zbirnem območju peloda.Ključne besede: Pelodna analiza, 14C datiranje, obrnjene paralelne akrecije

From spawner habitat selection to stock-recruitment: Implications for assessment

The relationship between the spawning stock size and subsequent number of recruits is a central concept in fisheries ecology. The influence of habitat selection of spawning individuals on the stock-recruitment relationship is poorly known. Here we explore how each of four different spawner behaviors might influence the stock-recruitment relationship and estimates of its parameters in the two most commonly used stock-recruitment functions (Beverton-Holt and Ricker). Using simulated stock-recruitment data generated by four different spawner behaviors applied to multiple discrete habitats, we show that when spawners were distributed proportionally to local carrying capacities, there was small or no bias in estimated recruitment and stock-recruitment parameters. For an ideal free distribution of spawners, larger bias in the estimates of recruitment and stock-recruitment parameters was obtained, whereas a random and a stepwise spawner behavior introduced the largest bias. Using stock-recruitment data corresponding to a "realistic " range of population densities and adding measurement error (20%-60%) to the simulated stock-recruitment data generated larger variation in the estimation bias than what was introduced by the spawner behavior. Thus, for exploited stocks at low population density and where spawning stock size and recruitment cannot be observed perfectly, partial observation of the possible spawner abundance range and measurement error might be of higher concern for management

Performance Based Logistics – A Norwegian-Swedish Perspective

Performance Based Logistics (PBL) as a support strategy for defence systems has been coined as a paradigmatic change within defence acquisition and maintenance. Originating from the defence industry, the concept has been adopted in many defence organisations. Although studies of its applicability has identified both enablers and barriers for implementation, these studies predominantly are performed in a few large nations. How the concept corresponds with a small state perspective needs to be addressed. Further on, perceived outputs of PBL practices would differ between the acquisition organisation, the supplier of PBL services, and the users of the services. Understanding these differences in perceptions would give valuable knowledge about how to design PBL contracts. Thirdly; assuming that PBL contracts indeed result in improved effectiveness, adapting the involved organisations to a new way of managing logistics should be accompanied by related organisational change processes. The purpose with this study is to contextualise the concept and define barriers and enablers for PBL in a small state perspective (represented by Norway and Sweden), identify different stakeholders’ expectations for output, and explore whether implementing such a concept is perceived as a significantly new way of organising defence supply chains with an accompanying organisational change strategy

Analysis of Sparse Representations Using Bi-Orthogonal Dictionaries

The sparse representation problem of recovering an N dimensional sparse vector x from M < N linear observations y = Dx given dictionary D is considered. The standard approach is to let the elements of the dictionary be independent and identically distributed (IID) zero-mean Gaussian and minimize the l1-norm of x under the constraint y = Dx. In this paper, the performance of l1-reconstruction is analyzed, when the dictionary is bi-orthogonal D = [O1 O2], where O1,O2 are independent and drawn uniformly according to the Haar measure on the group of orthogonal M x M matrices. By an application of the replica method, we obtain the critical conditions under which perfect l1-recovery is possible with bi-orthogonal dictionaries.Comment: 5 pages, 2 figures. The main result and numerical examples have been revise

Ungfiskundersøkelser, gytefisktelling i Nærøydalselva i 2021.

NORCE LFI har fått i oppdrag av Statkraft å overvåke utviklingen i bestandsstatus gjennom årlige ungfiskundersøkelser og resultater fra gytefisktelling i Nærøydalselva. I tillegg skal mulighetene for å gjennomføre habitattiltak som kan kompensere for reguleringspåvirkningen vurderes. Hensikten med slike tiltak vil være å bedre habitatet for laks og aure i vassdraget, og med det få økt fiskeproduksjon og bedre økologisk status i vassdraget.Ungfiskundersøkelser, gytefisktelling i Nærøydalselva i 2021.publishedVersio

Fiskebiologiske undersøkelser i Eidfjordvassdraget - Årsrapport for undersøkelser i 2022

Det er utført fiskebiologiske undersøkelser i Eidfjordvassdraget siden 2004. Denne rapporten er rapport for undersøkelsene gjort i 2022 og ettervinteren 2023, men inneholder også data for hele undersøkelsesperioden. Undersøkelsene er utført for å overvåke bestandene av laks og sjøaure i vassdraget, og for å evaluere tiltak for å styrke fiskebestandene. Undersøkelsene viser at gytebestandene av både laks og sjøaure har økt i årene etter 2010 sammenliknet med årene før. Gytebestandsmålet for laks har også vært nådd i enkelte av de siste årene, men bestandsstørrelsen har variert mellom år og forvaltningsmålet er ikke nådd. Bestanden av sjøaure kan i de senere årene karakteriseres som god. Tiltakene som så langt har vært gjennomført, har bidratt til at miljøbetingelsene i vassdraget har blitt bedre, men det anbefales at enkelte av tiltakene styrkes.publishedVersio

Fiskebiologiske undersøkelser i Eidfjordvassdraget - Rapport for undersøkelser i 2021

Eidfjordvassdraget munner ut i Eidfjord innerst i Hardangerfjordsystemet, og består av vassdragsavsnittene Bjoreio, Veig og Eio. Laksebestanden i Eidfjordvassdraget gikk kraftig tilbake på 1990-tallet, og har over lang tid vært kritisk lav. Vassdragsreguleringene på slutten av 1970-tallet har resultert i endringer i vannføring og temperaturforhold i vassdraget, og har hatt negative effekter på fiskebestandene i Bjoreio. Siden starten av 2000-tallet har det blitt gjennomført en rekke tiltak for å bedre bestandssituasjonen for laks og sjøaure. Viktige tiltak inkluderer slipp av vann fra Sysenmagasinet for å øke vintervannføring, slipp av vann fra vanninntakene i Isdal og Bjoreio sperredam ved Storlia for å øke sommertemperaturen, og utplanting av lakserogn fra genbanken. I perioden 2015-2021 er det også utført forsøk hvor klekkerismolt har blitt satt ut i vassdraget og/eller slept fra Eidfjordvassdraget og sluppet lenger ute i Hardangerfjorden.publishedVersio