TY - JOUR
T1 - Determination of Coscinodiscus cf. granii biovolume by confocal microscopy
T2 - Comparison of calculation models
AU - Roselli, Leonilde
AU - Stanca, Elena
AU - Paparella, Francesco
AU - Mastrolia, Annunziata
AU - Basset, Alberto
PY - 2013/1
Y1 - 2013/1
N2 - Biovolume is commonly used as a size descriptor in the study of phytoplankton ecology. Usually, biovolume is not measured directly but is obtained from a standardized set of geometric models based on linear dimensions measured by light microscopy. This commonly used method allows visualization and measurement in two dimensions (2D) yielding no information at all on the third dimension of phytoplankton cells. Inaccurate biovolume assessment resulting from geometric approximation leads to erroneous interpretation of eco-physiological processes and morpho-functional traits. Here, we use confocal microscopy coupled with an image analysis system (NIS Elements AR software, Nikon) to determine directly shape and biovolume by means a 3D reconstruction of Coscinodiscus cf. granii specimens. We evaluate the accuracy of current methods by comparing the results obtained using geometric models with direct biovolume and shape. We find that calculation of biovolume by approximation to geometric models (cylindrical and complex shapes) leads to a significant overestimation with respect to direct volume. We also propose a data-driven formula for calculating the biovolume of Coscinodiscus cf. granii specimens based on diameter or other linear measurements.
AB - Biovolume is commonly used as a size descriptor in the study of phytoplankton ecology. Usually, biovolume is not measured directly but is obtained from a standardized set of geometric models based on linear dimensions measured by light microscopy. This commonly used method allows visualization and measurement in two dimensions (2D) yielding no information at all on the third dimension of phytoplankton cells. Inaccurate biovolume assessment resulting from geometric approximation leads to erroneous interpretation of eco-physiological processes and morpho-functional traits. Here, we use confocal microscopy coupled with an image analysis system (NIS Elements AR software, Nikon) to determine directly shape and biovolume by means a 3D reconstruction of Coscinodiscus cf. granii specimens. We evaluate the accuracy of current methods by comparing the results obtained using geometric models with direct biovolume and shape. We find that calculation of biovolume by approximation to geometric models (cylindrical and complex shapes) leads to a significant overestimation with respect to direct volume. We also propose a data-driven formula for calculating the biovolume of Coscinodiscus cf. granii specimens based on diameter or other linear measurements.
KW - 3D-imaging
KW - Biovolume
KW - Confocal microscopy
KW - Coscinodiscus cf. granii
UR - http://www.scopus.com/inward/record.url?scp=84871955204&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871955204&partnerID=8YFLogxK
U2 - 10.1093/plankt/fbs069
DO - 10.1093/plankt/fbs069
M3 - Article
AN - SCOPUS:84871955204
SN - 0142-7873
VL - 35
SP - 135
EP - 145
JO - Journal of Plankton Research
JF - Journal of Plankton Research
IS - 1
ER -