Diversitet, abundans och variation i evertebratsamhällen i Fucus-bälten längs eutrofieringsgradienter
Salmela, Niilo (2021)
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2021060333417
https://urn.fi/URN:NBN:fi-fe2021060333417
Tiivistelmä
Blåstången (Fucus vesiculosus) är en viktig habitatbildande makroalg i norra Östersjön. Fucus-bälten utgör habitat för diversa evertebratsamhällen. Fucus och de associerade evertebraterna påverkas av eutrofieringen och ekologiska interaktioner. Det finns enbart lite forskning i stor skala om geografisk variation i evertebratsamhällen i Fucus längs eutrofieringsgradienter i norra Östersjön. Målet med denna avhandling är att få mera kunskap om denna variation. Sex delområden vid sydvästra Finlands kust med tre olika statusklass (dålig, tillfredsställande och god) valdes för att analysera den Fucus-associerade faunans samhällsstruktur. Jag studerade två del områden för varje statusklass. Provtagningen skedde genom att samla jämnstora Fucus-ruskor vars evertebratfauna togs till vara och artbestämdes, varefter abundanserna räknades och biomassan noterades. För att analysera samhällenas struktur beräknades Shannons diversitetsindex, Pielous jämnhetsindex och artantal, samt totalt individantal och biomassa. Dessa variabler jämfördes mellan de olika delområdena. Dessutom jämfördes de olika delområdenas artsammansättningar och olikheterna studerades. Skillnader mellan geografiska områden (delområdena) var större för Shannons diversitet, artantal, individantal och biomassa med de största skillnaderna mellan Skärgårdshavet och delområdena utanför. Individantal och biomassa visade dock samband med statusklasser: individantalet var högre i dålig status och biomassan i god status. Variationen i artsammansättningen påverkades av både vattenkvaliteten (statusklass) det geografiska området. Skillnaderna mellan geografiska områden var stora inom den dåliga statusklassen. -----------
Bladderwrack (Fucus vesiculosus) is an important habitat-forming species in the Northern Baltic Sea. The Fucus zone is an important habitat for invertebrate communities. Fucus and its associated invertebrate species are affected by eutrophication and biological interactions. There are not many large-scale studies about variation of invertebrate communities in Fucus habitats along eutrophication gradients in the Northern Baltic Sea. To acquire more information on this variation in invertebrate communities, six sub-areas were designated along South-West Finland’s coast covering three different status classes (bad, moderate, and good). There were two sub-areas to each status class. Sampling was done by collecting Fucus plants of similar size. The invertebrates associated with the macroalgae were identified, their abundances counted, and biomasses determined. To determine the structure of the invertebrate communities, Shannon’s diversity index, Pielous’ evenness index, and species richness; as well as the total abundance and biomass of species were assessed. These variables were compared between the sub-areas. Furthermore, species community composition was compared, and the dissimilarities were determined. The difference between geographical areas (the sub-areas) was more pronounced for Shannon’s diversity, species richness, abundance, and biomass. The biggest differences were between the Archipelago Sea and sub-areas outside of it. However, abundance and biomass seemed related also to the status classes: abundance was higher in bad status and biomass in good status. Variation in community composition was affected by water quality (status class) as well as by the geographical areas. Differences between geographical areas were considerable in areas in the bad status class.
Bladderwrack (Fucus vesiculosus) is an important habitat-forming species in the Northern Baltic Sea. The Fucus zone is an important habitat for invertebrate communities. Fucus and its associated invertebrate species are affected by eutrophication and biological interactions. There are not many large-scale studies about variation of invertebrate communities in Fucus habitats along eutrophication gradients in the Northern Baltic Sea. To acquire more information on this variation in invertebrate communities, six sub-areas were designated along South-West Finland’s coast covering three different status classes (bad, moderate, and good). There were two sub-areas to each status class. Sampling was done by collecting Fucus plants of similar size. The invertebrates associated with the macroalgae were identified, their abundances counted, and biomasses determined. To determine the structure of the invertebrate communities, Shannon’s diversity index, Pielous’ evenness index, and species richness; as well as the total abundance and biomass of species were assessed. These variables were compared between the sub-areas. Furthermore, species community composition was compared, and the dissimilarities were determined. The difference between geographical areas (the sub-areas) was more pronounced for Shannon’s diversity, species richness, abundance, and biomass. The biggest differences were between the Archipelago Sea and sub-areas outside of it. However, abundance and biomass seemed related also to the status classes: abundance was higher in bad status and biomass in good status. Variation in community composition was affected by water quality (status class) as well as by the geographical areas. Differences between geographical areas were considerable in areas in the bad status class.
Kokoelmat
- 1172 Ympäristötiede [13]