The Application of Long-Lived Bivalve Sclerochronology in Environmental Baseline Monitoring

Abstract

Assessments of the impact of construction, operation, and removal of large infrastructures and other human activities on the marine environment are limited because they do not fully quantify the background baseline conditions and relevant scales of natural variability. Baselines as defined in Environmental Impact Assessments typically reflect the status of the environment and its variability drawn from published literature and augmented with some short term site specific characterization. Consequently, it can be difficult to determine whether a change in the environment subsequent to industrial activity is within or outside the range of natural background variability representative of an area over decades or centuries. An innovative approach that shows some promise in overcoming the limitations of traditional baseline monitoring methodology involves the analysis of shell material (sclerochronology) from molluscs living upon or within the seabed in potentially affected areas. Bivalves especially can be effective biomonitors of their environment over a wide range of spatial and temporal scales. A rapidly expanding body of research has established that numerous characteristics of the environment can be reflected in morphological and geochemical properties of the carbonate material in bivalve shells, as well as in functional responses such as growth rates. In addition, the annual banding pattern in shells can provide an absolute chronometer of environmental variability and/or industrial effects. Further, some species of very long-lived bivalves can be crossdated back in time, like trees, by comparing these annual banding patterns in their shells. It is therefore feasible to develop extended timeseries of certain marine environmental variables that can provide important insights into long temporal scales of baseline variability. We review recent innovative work on the shell structure, morphology, and geochemistry of bivalves and conclude that they have substantial potential for use as monitors of environmental variability and the effects of pollutants and disturbance.

Unveiling the Ecological Applications of Ancient DNA From Mollusk Shells

“…Although most ancient DNA studies have focused on mammal bones and teeth (Green and Speller, 2017), new knowledge in ecology and evolution could be gained by applying ancient genomics to shell-producing mollusks (Coutellec, 2017). These animals indeed grow their carbonate shells in an incremental fashion, simultaneously recording biological and environmental data (Fortunato, 2015;Steinhardt et al, 2016;Butler et al, 2019), which can be tracked through a multitude of proxies, including morphology, isotopes (e.g., ∂ 18 O shell , ∂ 13 C shell ), trace elements and metal composition (e.g., Ba, Cd, Cu, Mo, Pb, U, Zn). The rich fossil record of mollusk shells, thus, provides an equally rich environmental archive of seawater paleo-temperature and salinity (Surge et al, 2003;Chauvaud et al, 2005;Hiebenthal et al, 2012;Vokhshoori and McCarthy, 2014;Reynolds et al, 2016;Black et al, 2017), pollution levels (Vander Putten et al, 2000;Liehr et al, 2005;Pérez-Mayol et al, 2014), stress (Hiebenthal et al, 2012;Trivellini et al, 2018), infection history (Paillard et al, 2004;Trinkler et al, 2010), as well as food availability and primary productivity (Lartaud et al, 2010;Sadler et al, 2012).…”

Shell Growth of Large Benthic Foraminifera under Heavy Metals Pollution: Implications for Geochemical Monitoring of Coastal Environments

“…Monitoring of heavy metals (HMs) in the marine environment is traditionally done by combining analyses of water, sediments, and tissues of the local biota. These compartments, especially the water-phase components (dissolved and particulate), provide a snapshot of the specific time of sampling and therefore require long-term recording [1,2]. Each method has its pros and cons; water analysis provides direct measurements of pollutant levels, but it is prone to overlooking events of temporally confined pollutant effluents since it is limited by the frequency of sampling.…”

“…Public Health 2020, 17, 3741 2 of 16 in the biological response (i.e., vital effects related to metabolism). Thus, the need for a long-term recording (i.e., bio-archive) is not resolved [2]. To overcome these disadvantages, chemical analysis of continuously accreting biomineralized structures (known as sclerochronology) was suggested as a bio-archive to document temporal trends in chemical pollution [2].…”

Calibrating Hall-Effect valvometers accounting for electromagnetic properties of the sensor and dynamic geometry of the bivalves shell

“…At present, diverse bivalve-based monitoring programs exist in many countries (Guégen et al, 2011), for shellfish aquaculture or environmental impact assessment purposes (e.g. Steinhardt et al, 2016).…”