Search results for "chironomidae"
showing 3 items of 53 documents
Recent changes in chironomid communities and hypolimnetic oxygen conditions relate to organic carbon in subarctic ecotonal lakes
2018
A key question in aquatic elemental cycling is related to the influence of bottom water oxygen conditions in regulating the burial and release of carbon under climate warming. In this study, we used head capsules of Chironomidae larvae to assess community and diversity change between the past (estimated as Pre-Industrial Period) and present and to reconstruct changes in hypolimnetic oxygen conditions from 30 subarctic ecotonal lakes (northeastern Lapland) using the top-bottom paleolimnological approach applying surface sediment (topmost 0-2 cm) and reference (4-5 cm) samples. Subsequently, we tested the findings against dissolved organic carbon (DOC) concentration of the sites. We found tha…
Lämpötilan vaikutus täpläravun (Pacifastacus leniusculus Dana) kasvuun sekä ravintotiheyden vaikutus täpläravun ja jokiravun (Astacus astacus L.) rav…
2016
Alun perin pohjoisamerikkalaisen täpläravun (Pacifastacus leniusculus Dana) levinneisyys on 1960-luvulta lähtien laajentunut kattamaan Etelä- ja Keski-Suomessa laajoja vesialueita, jotka ovat aiemmin olleet jokiravun (Astacus astacus L.) elinaluetta. Täpläravun mahdollisesti jokiravusta eroavaa ravinnonkulutusta ja saalislajeihin kohdistamaa saalistusta on pyritty arvioimaan täpläravulle kehitetyllä bioenergeettisellä mallilla, jonka jatkokehitystä ja toimivuuden arviointia tämä tutkimus tukee. Täpläravun kasvua selvitettiin 30 vrk:n ajan kolmessa Suomen luonnonoloja vastaavassa lämpötilassa, 10, 16 ja 22 °C:ssa. Ravintotiheyden vaikutusta täpläravun ja jokiravun mahdollisesti aktiiviseen k…
The adaptations to tube-dwelling life of Propsilocerus akamusi (Diptera: Chironomidae) larvae and its eutrophication-tolerant mechanisms
2019
Propsilocerus akamusi (Diptera: Chironomidae) is a dominant macroinvertebrate species in many eutrophic lakes in subtropical and temperate zones. P. akamusi larvae can migrate deep into the sediment (>30 cm) during summer where is no oxygen. However, to our knowledge, the specific adaptive tactics of its tube-dwelling life (>30 cm) and underlying mechanisms why this species is favored by nutrient-rich lakes remain limited. With the understanding above-mentioned issues, we can provide important information for the development of sensitive biomonitoring. We examined monthly morphological dynamics and physiological adaptations of P. akamusi to anoxic conditions, and environmental relationships…