Abstractbog printer - ansatte - Roskilde Universitet
Share Embed Flag
Download ePaper

Abstractbog printer - ansatte - Roskilde Universitet

Abstractbog printer - ansatte - Roskilde Universitet Abstractbog printer - ansatte - Roskilde Universitet

rucforsk.ruc.dk
from rucforsk.ruc.dk More from this publisher
26.07.2013 Views

Abstracts - S11 Stofomsætning i det marine miljø 78. Seasonal variations in plankton community production and respiration for Roskilde Fjord and Great Belt Mustafa Mantikci, Stiig Markager, Jørgen L. S. Hansen Bioscience, Aarhus Universitet, Frederiksborgvej 399, 4000 Roskilde amm@dmu.dk The seasonal patterns in plankton community production and respiration were investigated in the surface waters of two stations, Roskilde Fjord (RF) and Great Belt (GB), between January 2012 and July 2012. Generally, planktonic respiration has not been considered during several years of primary production research and even when taken into account, respiration measurements have done by dark bottle single start and end point oxygen measurements. In our study, community respiration rates were determined by continuous measurement of oxygen consumption in darkness for 48 hours. Preceding the respiration measurement, we determined photosynthetic rates as a function of irradiance by the 14 C technique by 2 hours of light incubation in a linear incubator. Oxygen concentrations were measured with optodes (fiber-optic oxygen meter) by using oxygen sensor spots that was fixed to the inner wall of 60 ml BOD bottles. Respiration rates were calculated by fitting a model to the raw data which assumes respiration decreases exponentially from an initial value, R0, approaching a constant “Maintenance” respiration, Rm. Maximum photosynthesis (Pmax) normalized to Chl-a values increased markedly over the 6-month sampling period, from 0.9 to 3.8 and 0.7 to 6.5 gC g -1 Chl-a h -1 at GB and RF respectively and was significantly correlated with temperature. R0 varied between 0.1 and 1.9 µmolO2l -1 h -1 and Rm varied from 0.02 to 0.6 µmol O2 l - 1 h -1 Rm was significantly correlated with temperature, POC and Pmax. Q10 values for POC turnover and Pmax of 2.5 and 2 respectively suggests community respiration was much more sensitive to temperature than photosynthesis in the study areas. Future studies will focus on the role of light history on dark respiration and the calculation of GPP and P:R ratios more accurately in order to understand carbon cycle at the pelagic systems. This work increases our understanding of planktonic respiration and its relationship with biotic and abiotic factors. Program 17. danske havforskermøde, 102

Abstracts - S11 Stofomsætning i det marine miljø 79. Seksuel selektion hos en pelagisk copepod, Temora longicornis Mie Hylstofte Sichlau, Einar Eg Nielsen, Thomas Kiørboe DTU Aqua mhsi@aqua.dtu.dk, een@aqua.dtu.dk, tk@aqua.dtu.dk Nye studier har vist at parring hos pelagiske copepoder ikke er så tilfældig som hidtil antaget. Vi har ved hjælp af parringsforsøg og genetiske analyser af faderskab undersøgt styrken af seksuel selektion hos en pelagisk copepod, Temora longicornis. Vi har identificeret og karakteriseret 9 mikrosatellitter for Temora longicornis. Vi fandt at store eller unge hanner befrugter relativt flere hunner sammenlignet med mindre eller ældre hanner. Disse hanner giver hermed afkast til flere afkom. Begge køn af Temora longicornis er promiskuøse og mikrosatellit analyser viste, at der kan være flere fædre til et enkelt batch af æg fra en hun. Dermed øges den genetiske variation hos afkommet. Parring med flere hanner har imidlertid en omkostning, idet flere parringer fører til en forhøjet mortalitet. Vores undersøgelser bidrager til forståelsen af parringsadfærd og hvor vigtig seksuel selektion er hos Temora longicornis. Program 17. danske havforskermøde, 103

Abstracts - S11 Stofomsætning i det marine miljø<br />

79. Seksuel selektion hos en pelagisk copepod, Temora longicornis<br />

Mie Hylstofte Sichlau, Einar Eg Nielsen, Thomas Kiørboe<br />

DTU Aqua mhsi@aqua.dtu.dk, een@aqua.dtu.dk, tk@aqua.dtu.dk<br />

Nye studier har vist at parring hos pelagiske copepoder ikke er så tilfældig som hidtil antaget. Vi<br />

har ved hjælp af parringsforsøg og genetiske analyser af faderskab undersøgt styrken af seksuel<br />

selektion hos en pelagisk copepod, Temora longicornis. Vi har identificeret og karakteriseret 9<br />

mikrosatellitter for Temora longicornis. Vi fandt at store eller unge hanner befrugter relativt flere<br />

hunner sammenlignet med mindre eller ældre hanner. Disse hanner giver hermed afkast til flere<br />

afkom. Begge køn af Temora longicornis er promiskuøse og mikrosatellit analyser viste, at der kan<br />

være flere fædre til et enkelt batch af æg fra en hun. Dermed øges den genetiske variation hos<br />

afkommet. Parring med flere hanner har imidlertid en omkostning, idet flere parringer fører til en<br />

forhøjet mortalitet. Vores undersøgelser bidrager til forståelsen af parringsadfærd og hvor vigtig<br />

seksuel selektion er hos Temora longicornis.<br />

Program 17. danske havforskermøde, 103

logo

products

Resources

Company

Terms of service
Privacy policy
Cookie policy
Cookie settings
Imprint
Change language
Made with love in Switzerland
© 2024 Yumpu.com all rights reserved

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!