Is the umbo matrix of bivalve shells (Laternula elliptica) a climate archive?

Abstract

Heavy metal accumulation into bivalve soft tissues has received increasing interest in recent years with respect to biomonitoring of environmental change including pollution. To a lesser extent, accretion of elements from the environment into bivalve hard structures (shells) has been investigated, although the importance of the shells as environmental archives has been acknowledged. Here we report element distribution within consecutive growth bands in the shells of the Antarctic soft shell clam Laternula elliptica, which is currently exposed to vast environmental change in Antarctic Peninsula coastal environments that undergo rapid climate warming. We performed a high spatial resolution analysis for Al, Fe, Mn, Cu, Pb and U in the shell umbo, by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Element ratios within the umbo did not resemble either the ratios in the surrounding seawater, the sedimenting material in Potter Cove, or even the Earth's crust basal composition. Mn and Cu were preferentially incorporated into the umbo. A strong decrease of element accretion with time could be related to lifetime respiration mass (R) of the animals. This indicates element accretion into the umbo and shell matrix to be largely a function of animal ecophysiology and life history, and these effects need to be considered in the context of potential usefulness of L. elliptica shells as environmental archives.

On the phytoplankton bloom in coastal waters of southern King George Island (Antarctica) in January 2010: An exceptional feature?

“…Nutrient (nitrate and phosphate) concentrations, as shown for both years 2010 and 2011 for both PC and AB, and as previously determined for the study area (Schloss and Ferreyra 2002), were not limiting phytoplankton growth; micronutrients such as iron (Fe) have been shown to abound in particles generated by subglacial erosion and thus Fe appears nonlimiting in the PC area (Dick et al 2007), as also generally observed in the region of the South Shetland Islands, which are sources of natural iron enrichment in the Antarctic Peninsula region (De Jong et al 2012). Phytoplankton cells might therefore grow and accumulate when physical conditions are adequate for it, although this has not been previously observed to the extent found in the present work.…”

Differences in heavy metal concentrations and in the response of the antioxidant system to hypoxia and air exposure in the Antarctic limpet Nacella concinna

“…However, other factors such as increased input of lithogenic particles from underneath melting glaciers and from eroding land surfaces during the austral summer (Ahn et al, 1997;Klöser et al, 1994;Yoo et al, 1999) are bound to primarily affect the sub-littoral limpet fauna in the coastal environment of this volcanic archipelago (Ahn et al, 2002). Plumes of volcanic rock sediments carry high concentrations of heavy metals including Fe, Al, Cu and Zn into the nearshore waters of the South Shetland Archipelago Dick et al, 2007), and similar phenomena are described from areas along the maritime AP (Dierssen et al, 2002). Once taken up by sedimentary grazers or benthic filter feeders, these metals can exacerbate oxidative stress in animal tissues.…”

Eficiencia de la tinción de bandas de crecimiento con calceina y azul de coomassie, para estimar la edad de jóvenes de Pinctada mazatlanica (Pterioida: Pteriidae)

“…In addition, Dick, Philipp, Kriews, & Abele (2007) detected a faster growing and respiratory rate in younger individuals than older ones of other bivalves, with higher accumulation of heavy metals in their shells during polymerization. This shows a less discrimination between wanted and unwanted material in younger individuals.…”