Search results for "hiekka"
showing 4 items of 4 documents
Effect of substrate particle size on burrowing of the juvenile freshwater pearl mussel Margaritifera margaritifera
2021
AbstractJuveniles of the endangered freshwater pearl mussel (FPM,Margaritifera margaritifera) live burrowed in stream substrate for the first years of their life. Fine sediments block water exchange within substrate and may cause juvenile mortality and recruitment failure. To better understand the connection between success of juvenile FPM and substrate particle size, it would be important to understand behavioural responses of FPM to varying substrate sizes at this critical life stage. We placed newly detached FPM juveniles in a 7-mm layer of sieved sand sorted into five sizes (< 120, 120–200, 200–250, 250–500 and 500–650 µm) each with 10 replicate dishes, 10 juveniles per dish, with bu…
Macrobiotus naginae sp. nov., a New Xerophilous Tardigrade Species from Rokua Sand Dunes (Finland)
2022
Animals that colonize soil show specific adaptations to soil. Compared to closely related species living on the surface, the limbs of soil-dwelling animals are often shortened, reduced, or absent to allow a less restricted passage through cavities between soil particles. This pattern of limb reduction has also been observed in tardigrades, where multiple lineages that colonized the below-ground habitat show independent reduction and/or loss of legs and claws. In the tardigrade superfamily Macrobiotoidea, leg and claw reductions are a common trait found in the Macrobiotus pseudohufelandi complex. This rarely found species complex currently contains four nominal taxa. Here we describe, with t…
Kasviyhteisöjen sukkessio ja lajimäärä maanottoalueilla
2016
Aktiivisen käytön päätyttyä maanottoalueet, kuten hiekka- ja sorakuopat, vapautuvat laajamittaiselle kasvillisuuden kehitykselle. Oton seurauksena maaperän siemenpankki häviää, joten kasvillisuuden muodostuminen on täysin riippuvaista ympäröiviltä alueilta leviävistä siemenistä ja itiöistä. Kaikki kasvilajit eivät kuitenkaan selviä ottoalueiden vaativissa olosuhteissa ja selviytyjienkin kasvu on usein hidasta. Lisäksi alueet ovat alttiita sekä luonnollisille että ihmisten aiheuttamille häiriöille, jotka hidastavat kasvillisuuden kehitystä entisestään. Jälkihoitotoimenpiteinä maanottoalueilla tasataan reunaluiskia ja istutetaan mäntyä, joilla pyritään vähentämään eroosiota ja kiihdyttämään o…
Sand Play for 0–8-Year-Old Children’s Health and Development: A Systematic Review Protocol
2021
Sand play may be a significant determinant of health and development in early childhood, but systematically synthesised evidence is absent in the literature. The main objective of this study was to present a planned methodology to systematically review, and synthesise, the evidence regarding sand play and its associations with 0–8-year-old children’s health and development. The systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols statement was registered to PROSPERO (CRD42021253852). Literature searches will be conducted using information from eight electronic databases. Studies will be included when participating children were aged 0–…