Resource-use of crucian carp (Carassius carassius) in lakes with different predation risk

Predator fish and prey its prey can have considerable effect on fish communities and can affect the behavior of its prey. stable isotope of carbon (d13C) and nitrogen (d15N can provide as a powerful and useful tool for estimating trophic position, littoral reliance and niche width for food webs in freshwater lakes. Twelve crucian carp lakes were sampled in southeast Norway. Three allopatric lakes with no predators, three lakes with Eurasian perch (Perca fluviatilis), three brown trout (Salmo trutta) and three with northern pike (Esox lucius) as top predators. With fish species richness varying from 1 – 7 fish species. I calculated the trophic position, littoral reliance and examined littoral vs pelagic use, and compared the niche width of crucian carp in the four different regimes. I expect, 1; that crucian carp will shift from pelagic resource use to littoral in lakes with predation, 2; that trophic position will be lower in lakes with predation and 3; the niche of crucian carp will be smaller in a more complex system. Results show that piscivore top predators influence littoral use and trophic position for crucian carp, and that the niche width changes in more complex systems. Thus, I conclude that piscivore top predators have an effect the structure and function of crucian carp communities

Editors\u27 Notes: Offering a Visionary Reality - Architecture as Fiction

This mixed issue presents five scientific articles and three book reviews. The articles have been framed by the initial phase of a potential theme discussion on architecture as fictio

EDITORS’ NOTES ON STRATEGIES FOR PUBLISHING RESEARCH IN ARCHITECTURE AND LANDSCAPE ARCHITECTURE IN THE NORDIC COUNTRIES, No 1-2023

This mixed issue presents four scientific articles and three book reviews. The articles have been supplemented by a survey on strategies for publishing architectural research in the Nordic countries. To provide a background picture of how research is disseminated, we have asked the architecture and landscape architecture departments at universities in the Nordic countries if they have formulated a publication strategy for research. Several of them have kindly responded substantially to our request. Overall, the responsibility for disseminating research seems to be a concern for the individual researcher rather than the institution. Each scholar at the university or school of architecture must on their own behalf identify the best publication channel for communicating research findings to potential target groups as part of their public outreach activities

Real estate agent´s challenges in investing in Real estate

Bacheloroppgave i eiendomsmegling 2017Bacheloroppgaven tar utgangspunkt i Eiendomsmeglingsloven av 29.06.2007, med ikrafttredelse 01.01.2008. Den nye eiendomsmeglingsloven regulerte eiendomsmeglingsbransjen på et nytt nivå, og gjør tydelig rede for hvilke rammer som gjelder for det helhetlige av eiendomsmeglingsutførelsen. Vi har hovedsakelig fokusert på emgll. § 5-3 forbud mot egenhandel, § 6-3 God meglerskikk og § 5-2 ansattes adgang til å drive næringsvirksomhet. Som en sentral del av oppgaven har vi tatt utgangspunkt i Finanstilsynets rundskriv 7/2015 ”Høvet til å gjere langsiktige investeringar i fast eigedom” (Finanstilsynet, 2015) som ytterligere redegjør for gjeldende lov, retningslinjer og praksis rundt kjøp og salg av eiendom av praktiserende eiendomsmeglere. Så lenge reguleringen av eiendomsmegleres adgang til handel for egen interesse foreligger, med de rammer dette medfører, ønsker vi å belyse hvordan dette faktisk praktiseres, og tillates. ”Er det behov for en så omfattende regulering av eiendomsmeglers mulighet til å investere i fast eiendom?” Spørsmålet stammer tilbake til eiendomsmeglingsyrkets oppstandelse. Behovet for regulering er absolutt tilstede, men i hvilken grad? Er det hensiktsmessig å tillate, eventuelt lempe på krav og rammer? Dette er spørsmål vi opplever som svært sentrale, og har stor egeninteresse av å belyse å finne svar på. Vi har i oppgaven gjennomført en spørreundersøkelse mot eiendomsmeglere, intervjuet fagansvarlige ved eiendomsmeglingsforetak for å belyse hvordan dette fungerer i praksis, samt fått en uttalelse av en representant fra finanstilsynet. Dette har vært svært nyttig for å se på problemstillingen fra en annen side enn kun den teoribaserte. I løpet av arbeidet med oppgaven har vi etter dialog med sentrale personer innenfor temaet, ved hjelp av undersøkelser og ved å studere rundskriv og lover, fått et bedre innblikk og bredere forståelse. Det er sentralt hvordan regelverket er bygget opp, hvordan de enkelte meglere og foretak foretar registrering, kontroll og etterlever de rammene som er fastsatt for eiendomsmeglere. Oppgaven har hoveddel i et juridisk aspekt, og det er i oppgaven vektlagt finanstilsynets rundskriv. Vi anser dette som en nærmere beskrivelse og mer tydelig retningslinje for hvordan investering i eiendom for eiendomsmeglere skal foregå.Engelsk sammendrag The thesis is based on “Eiendomsmeglingslova” 29.06.2007 (emgll), with effect from 01.01.2008. The new estate brokerage regulation regulated the real estate industry at a new level, and clearly explains what frameworks apply to the overall real estate performance. We have mainly focused on emgll. Section 5-3 Prohibition of Self-Commerce, Section 6-3 Good Brokerage and Section 5-2 Employee Access to Operate Business. As a central part of the assignment, we have based on Finanstilsynets rundskriv 7/2015 ”Høvet til å gjere langsiktige investeringar i fast eigedom” (Finanstilsynet, 2015) which further explains current legislation, guidelines and practices regarding the purchase and sale of property by practitioners Real estate agents. As long as the regulation of real estate agents' access to trading for their own interest is available, with the resulting framework, we wish to illustrate how this is actually practiced and allowed. "Is there a need for such a comprehensive regulation of real estate agents' ability to invest in real estate?" The question comes back to the resurrection of the real estate agency. The need for regulation is absolutely present, but to what extent? Is it appropriate to allow, possibly reduce the requirements and limits? These are questions we perceive as very central, and have great self-interest in illuminating finding answers. We have carried out a survey of real estate agents, non-skilled professionals at real estate agencies, to explain how this works in practice, as well as a statement by a representative from the Danish Financial Supervisory Authority. This has been very useful for looking at the problem from another side, just the theory-based. During the course of the assignment, we have had dialogue with key persons within the subject, by means of studies and by studying circular and laws, gaining a better insight and broader understanding. It is central to how the regulations are built up, how individual brokers and enterprises make registration, control and compliance with the framework set for real estate agents. The assignment is a part of a legal aspect, and the circular is emphasized in the task. We consider this as a more detailed description and more clear guideline for how investment in real estate for real estate agents should take place

Resource use of crucian carp along a lake productivity gradient is related to body size, predation risk, and resource competition

Generalist fish species can feed on a wide resource spectrum and across trophic levels depending on resource availability and trophic interactions. Crucian carp (Carassius carassius) represents a good candidate species to investigate variation in the trophic ecology of generalist fish as it can be found in highly variable fish communities and its resource use is well documented. In this study, we explored the trophic ecology of crucian carp at the individual and population levels using stable isotope and gut content analysis. We tested if trophic resource use varied according to lake productivity, predation risk, intra- and interspecific competition, or individual fish size. We found that crucian carp resource preference was highly variable among and within lakes. In predator-free lakes, small crucian carp occurred in high densities, showed increased interindividual specialisation, and relied mainly on pelagic zooplankton. In presence of predators, large crucian carp occurred in low densities and included greater proportions of benthic macroinvertebrates in their diet. This shift in resource use was further favoured in productive, shallow lakes where littoral prey were probably abundant. Resource partitioning was an important factor determining crucian carp niche use, as fish had higher trophic position in absence of other cyprinids. Crucian carp showed highly dynamic resource use and food preferences in response to variable environmental conditions. Overlooking complex diet preferences of generalist fish may lead to an oversimplification of freshwater community dynamics.Peer reviewe

Resource use of crucian carp along a lake productivity gradient is related to body size, predation risk, and resource competition

Generalist fish species can feed on a wide resource spectrum and across trophic levels depending on resource availability and trophic interactions. Crucian carp (Carassius carassius) represents a good candidate species to investigate variation in the trophic ecology of generalist fish as it can be found in highly variable fish communities and its resource use is well documented. In this study, we explored the trophic ecology of crucian carp at the individual and population levels using stable isotope and gut content analysis. We tested if trophic resource use varied according to lake productivity, predation risk, intra- and interspecific competition, or individual fish size. We found that crucian carp resource preference was highly variable among and within lakes. In predator-free lakes, small crucian carp occurred in high densities, showed increased interindividual specialisation, and relied mainly on pelagic zooplankton. In presence of predators, large crucian carp occurred in low densities and included greater proportions of benthic macroinvertebrates in their diet. This shift in resource use was further favoured in productive, shallow lakes where littoral prey was probably abundant. Resource partitioning was an important factor determining crucian carp niche use, as fish had higher trophic position in absence of other cyprinids. Crucian carp showed highly dynamic resource use and food preferences in response to variable environmental conditions. Overlooking complex diet preferences of generalist fish may lead to an oversimplification of freshwater community dynamics.publishedVersio