I denna rapport presenteras en studie vars syfte är att undersöka vilken vikt lärarna lägger vid artkunskap i gymnasieskolans ekologiundervisning, samt vad lärarna anser att artkunskap har för betydelse för förståelsen av ekologiska samband. Studien undersöker också om det föreligger något samband mellan elevernas artkunskap och deras förståelse för ekologi. Sex lärare har intervjuats om sin ekologiundervisning och art- och ekologitester har genomförts med elever från lika många klasser inom naturvetarprogrammet. Lärarna understryker vikten av artkunskap för att eleverna skall förstå ekologiska samband. En övervägande del av lärarna har också ett stort artfokus i sin ekologiundervisning. Artstudierna bedrivs huvudsakligen i samband med exkursioner. För att artkunskap skall tjäna ett syfte i undervisningen betonas vikten av att sätta arterna i ett sammanhang. Artkunskapen ökar då förståelsen för ekologisk processer och för ekosystemens dynamik. Studien påvisar samband mellan elevernas artkunskap och förståelsen för ekologi. Denna studie stödjer därmed tidigare forskning kring artkunskapens betydelse inom ekologiundervisningen.

Diss. Uppsala : Uppsala universitet, 2007.

Diss. Umeå : Umeå universitet, 2007.

Ecological differentiation and adaptation are processes that can drive divergence and speciation. Measuring ecologically revenant traits can help to identify possible targets of natural selection that may have mediated ecological differentiation. This study looked for evidence of within and between species differentiation in seven ecologically relevant traits in two closely related species sampled across their range, and whether any of these traits were related to climate differences among site of origin. We measured seven traits under common garden conditions in seedlings of Silene dioica (11 populations, n=528) and Silene latifolia (14 populations, n=672) grown in the botanical garden in Uppsala in a randomised block design. Three traits related to leaf morphology were measured, and four related to water usage of the plant were measured. These traits were analysed for differences between the species as well as for differences within each species between populations using a linear mixed model. The traits’ relationship to a climate variable, derived from the axes of a principal components analysis of climate data for each site, was investigated using a linear model. A number of drought avoidance (e.g. succulence, max turgid weight) and morphological traits (e.g. leaf ratio) differed between the two species. Water use efficiency has been flagged before as possibly driving ecological differentiation between the two species and the results identify possible candidate traits for quantifying this separation. Differentiation between populations within each species was also present in two traits within S. latifolia and in four traits within S. dioica significantly varying between the populations. This could reflect either local adaptation or genetic drift acting on populations across the range. One trait related to the amount of water taken up by the leaf (wgain) was found to be significantly associated with the climate variable, which was extracted from the principal components analysis, in S. latifolia. The results identified a number of candidate traits which could reflect ecological differences between the species especially with respect to water relations. These traits may allow the species to respond differently during periods of water stress, which in turn could result in ecological separation of the species and determine their geographical ranges.

Competition is common between closely related species, no less between birds. For tits in temperate forests, competition for food and space is usually stronger during winter, as foraging opportunities are few. Many species with an otherwise broad diet, therefore,  start eating the same available food items and thus increase their overlap in the use of food resources. The purpose of this study was to investigate whether coal tits and marsh tits compete with each other. The observations were made in 10 selected locations with varying types of forests. In the study, 20 entrants and 20 blacks were observed for 5 minutes per individual. Every minute the position of the individual was noted in the tree.The results indicate an asymmetrical competition between the species because marsh tits changed its habitat use and were found lower in trees in the presence of coal tits, whereas coal tits did not change its habitat use in the presence of marsh tits. The movement by the Marsh tits can then reduce competition and give both species a better chance of living together. / Konkurrens är vanligt mellan närbesläktade arter, inte minst mellan fåglar. Konkurrensen om mat och boplatser blir oftast starkare på vinterhalvåret då det är svårare att hitta mat och många arter som annars föredrar olika sorters föda då börjar äta samma sort. Syftet med denna studie var att undersöka om svartmes och entita konkurrerar med varandra. Observationerna gjordes på 10 utvalda platser med varierande skogstyper. I studien observerades 20 entitor och 20 svartmesar i 5 minuter per individ. Varje minut noterades individens position i trädet. Resultaten visar att det kan förekomma en asymmetrisk konkurrens mellan arterna då entitan flyttade sig nedåt i höjdnivå i närvaro av svartmes, medan svartmes inte ändrade plats i närvaro av entita. Entitans nedflyttning kan då minska konkurrensen och ge båda arter bättre möjlighet till samlevnad.

Chemical pollutants are one of the main threats against biodiversity and chemicals affecting non-target organisms are of great environmental concern. The herbicide triclopyr is commonly used to keep weeds under control and is believed to be weakly toxic to animals and only lethal in high doses. However, the knowledge of possible sub-lethal behavior effects in low doses is scarce. This study investigates whether the wood ant (family Formica) show behavioral changes when exposed to sub-lethal doses of triclopyr. The main hypotheses tested were; i) ants behaving normally show a preference for dark surfaces (i.e. scototaxis); and ii) triclopyr affect this behavior trait among ants. The hypotheses were tested by exposing ants to diets containing 1, 10 and 100 mg/L triclopyr for 24 hours (acute) and 7 days (chronic). To what extent ants preferred the white surface (proportion of frames with the ant visible), their activity (proportion of speed above 1 mm/s) their exploration (proportion area covered) and their average velocities was measured using a newly developed tracking software (ToxTrac). The results clearly show that ants have preference for dark surfaces and thus, that the first hypothesis is valid. However, the second hypothesis appear invalid as the different exposures to triclopyr did not affect the examined behaviors. Based on the results, triclopyr appear to not affect non-target organism such as ants, although possible behavioral effects in other organisms and other behavioral traits cannot be excluded.

A decline in the density of zoobenthos has taken place in Lake Abiskojaure in the northern Swedish mountains between 1988 and 2019 but no response can be seen in the abundance (CPUE) of Arctic charr (Salvelinus alpinus) that feed mainly on benthic invertebrates. To evaluate if possible shifts in resource use of charr explain this lack of change in population abundance, stomach contents (i.e. diet) of charr between 1985 and 2020 were analyzed. Charr diets changed during the study period, with decreasing contributions to the diet of larger sized prey and increasing contribution of smaller sized prey and zooplankton. A corresponding recent decline in charr growth, size, and condition factor was observed. The proportion of large prey in diets and charr growth both show a hump-shaped relationship with time before the recent decline, indicating consumption of large prey had a positive effect on charr growth. Densities of zooplankton in the lake did not change with time, meaning increases in diet proportions are driven by something else. Declines in nitrogen and phosphorous over time may have contributed to the decline in zoobenthos densities through nutrient limitation of primary production. The results from this study suggest charr has changed diet towards smaller, less energetically efficient prey as a response to declining zoobenthos levels, and that this has had a negative effect on charr growth, size, and condition factor. Additional declines in nutrients and zoobenthos abundance may further worsen charr performance and eventually be manifested as declining charr abundance.

Kantzoner längst vattendrag i skogen är en komplex och artrik miljö som är av stor vikt för flertalet arter. Ett stort hot mot kantzoner är skogsindustrin och främst kalavverkning som kan ha en negativ effekt på hela ekosystem. Det finns idag ingen lag som kräver att kantzoner längst vattendrag bevaras med det rekommenderas. En kalavverkning kan minska tillförsel av nedfall som terrestra invertebrater till vattendraget med så mycket som en tredjedel, även om en kantzon på 30 meter bevaras. Tillförsel av terrestra invertebrater till vattendragen är av stor vikt då det kan utgöra upp till 50% av energiintaget hos fisk. Frånvaro av terrestra invertebrater skulle kunna leda till en ökad biomassa av perifyton och en minskad tillväxt hos fisk. För att undersöka om kantzonernas bredd längst vattendrag i skogen påverkar nedfallet av invertebrater till vattendraget genomförs en fältstudie. 17 lokaler har besökts i studien där fällor placerats ut på två ställen längst en 100 meters sträcka. Fällornas innehåll sorterades sedan till ordning. Krontäckningen kontrollerades även på varje lokal och vegetationen inventerades. Regressionsanalys, HCA, PCA och korrelationsanalys utfördes. Efter analys indikerade resultatet på att det är vegetationens sammansättning som är den viktigaste faktorn. Lokaler med mycket örter och bar jord hade en större förekomst av individer och ordningar. Detta kan bero på att ett kalhygge släpper in mer ljus och värme. Avverkade områden kan ha högre näringsvärde vilket kan gynna flertalet arter. Lokalerna som besöktes i studien var förhållandevis ung produktionsskog vilket kan även ha spelat in då dessa skogar har en relativt låg biodiversitet. Vid planering och konstruktion av kantzoner längst skogliga vattendrag bör det prioriteras att skapa kantzoner av god ekologisk status. / Riparian forests is a complex and species-rich environment that is of great importance for many species. A big threat to the riparian forests is the forest industry and mainly clear-cut felling, which can have a negative effect on entire ecosystems. There is currently no law that requires that buffer zones along forest streams be preserved, it is however recommended. A clear cut can reduce the input of to the stream by as much as a third, even if a buffer zone of 30 meters is preserved. The input of terrestrial invertebrates to streams is of great importance as it can account for up to 50% of the energy intake of fish. An absence of terrestrial invertebrates could lead to increased periphyton biomass and reduced growth in fish. A field study was performed to investigate if the buffer width effects the input of terrestrial invertebrates. 17 sites were visited where traps were placed at two placed along a 100 stretch. The content of the traps was then sorted into order. The canopy cover was controlled, and the vegetation was inventoried. Regression analysis, HCA, PCA and correlation analysis was performed. After analysis, the results indicated that it is the composition of the vegetation that is the most important factor. Sites with a lot of herbs and bare soil had a greater presence of individuals and orders. This may be because clear cuts let in mor e light and heat, they can also have a higher nutritional value which can benefit several species. The sites visited in the study were relatively young production forest which also may have played a role as these forests have a relatively low biodiversity. When planning and constructing buffer zones along forest streams, it should be prioritized to creating buffer zones of good ecological status.

Homogenous forests, such as forests managed for timber harvest, have caused a lot of discussion regarding the effect they have on biodiversity. Many studies have been done comparing the presence of organism groups and species between different types of forest and the production forests to better understand the effect production forests have on biodiversity. However, few studies have focused on how the bryophyte community is affected by these forests. In this study I study seven indicator moss species and compare their occurrence between nature reserves and production forests in Örebro municipality. These indicator species are used when evaluating if a forest has habitats that are of importance for red-listed species. When doing the inventory, I searched for potential habitat in the forests and tried to locate these species. I found that there were significantly more indicator species per inventoried area in the nature reserves than in the production forests. Furthermore, the density of the mosses was significantly higher in the nature reserves than in the production forests. These results suggest that habitats that are important for the indicator species and thus, the red-listed species are more scarce in the production forests.

Akvariehobbyn omfattar mer än 120 länder världen över och handeln med levande akvariefisk omsätter globalt mer än $330 miljoner varje år. En av de fiskgrupper som dragit till sig stort intresse är ciklider (Cichlidae) och en stor mångfald av dessa hittar man inom Neotropiska flodsystem. Flertalet av de ciklider som återfinns i Syd- och Centralamerika fångas för att sedan exporteras som akvariefisk till den västerländska akvariehobbyn. Det finns få källor som indikerar på att detta fiske har en övervägande negativ påverkan på naturliga populationer. Studier på fiskare i Amazonas visar att de fortfarande kan utvinna samma mängd fisk som för femtio år sedan. Vid minst ett fall har man sett en överexploatering av akvariefisk vid användandet av mer industrialiserade fisketekniker och detta fiske ledde snabbt till populationskollaps. Fisket i Amazonas bedrivs för övrigt småskaligt och med skonsamma fiskemetoder. Av denna anledning finns det forskare som hävdar att verksamheten istället har många positiva effekter för både de människor som bedriver fisket och de naturområden där fisket äger rum.