CHAPTER 12
Evaluation of Biological Stress Indices in Tapes philippinarum
from the Lagoon of Venice through Monitoring
of Natural Populations and Transplantation Experiments
M.G. MarinI, N. Nestol, and L. Da Rosl
ABSTRACT
Monitoring of natural populations ofthe clam Tapes philippinarumfrom two sites in the Lagoon
of Venice was carried out together with a transplantation experiment. The sites were chosen for
their different hydrological conditions and pollution levels. Several physiological and histochemical stress-related parameters have been measured. Clearance rate and scope for growth
are significantly affected by higher anthropogenic contamination levels acting on natural clam
bedst though they are not responsive in transplanted animals after a six-week exposure. On the
contrary "survival in air" response and lysosomal latency time are confirmed as early warning
indices, particularly suitable for both monitoring approaches. Clam T. phifippinarum is proposed
as an indicator species in order to obtain an integrated biological evaluation of coastal seawater
and sediment quality.
Introduction
Bivalve molluscs are commonly used as indicator
organisms in evaluating the environmental quality of marine coastal ecosystems, mostly for their
sessile and ftlter-feeding habits (Goldberg et al.
1978). Two different approaches have been followed, naDIely: (l) measuring the bioaccumulation of organic and inorganic chemical contaminants in target organs or in whole tissues (evaluation of the contaminant body burden); (2)
quantifying biological responses to environmental stress (evaluation of biomarkers of exposure).
Monitoring programmes can be carried out on
both native and transplanted populations, the
latter technique being based on the comparison
of chemical and/or biological characteristics in
samples collected from one population and
exposed, after translocation, to different environmental conditions. The advantages of experimental exposure through translocation experiments are based on the possibility to expose
organisms with common life history and genetic
make up at sites to be monitored at investigators'
choice (de Kock and Kramer 1994).
In the present studies, several physiological
and histochemical stress-related parameters
have been monitored in two natural populations
of the clam Tapes philippinarum and after a
transplantation experiment at the same locations
in the Lagoon of Venice.
The sampling sites were chosen on the basis
of their organic and trace metal contaminants
level, reflecting different anthropogenic impact
(Martin et ala 1994; Fattore et ala 1997a, 1997b;
Frignani et ala 1997).
Materials and Methods
Two natural populations of T. philippinarum, one
from a polluted industrial area, Porto Marghera,
and the second one from a relatively clean site
though featuring highly variable hydrologic
parameters, like temperature, salinity and dissolved oxygen, Palude della Rosa (Bianchi et al.
1997), were monitored twice a year. Moreover, a
transplantation experiment was carried out on
organisms taken from a reference commercial
growing area (Val Dog!) and translocated for six
weeks at the SaDIe monitoring sites. Samplings
on natural populations were performed in April
and July, and the transplantation experiment in
April. 1998. While SaDIpling the dams, the water
1 Dipartimento ill Biologia, Universita ill Padova, Via G. Colombo 3,35121 Padova. Italy
z Istituto di Biologia Marina, CNR, Castello 13641A. 30122 Venezia, Italy
F.M. Faranda, L Guglielmo, G. Sperle (eds)
Mediterranean Ecosystems: Structures and Processes
@ Springer-Verlag ltalia 2001
Evaluation of Biological Stress Indices in Tapes philippinarum
from the Lagoon of Venice through Monitoring
of Natural Populations and Transplantation Experiments
M.G. MarinI, N. Nestol, and L. Da Rosl
ABSTRACT
Monitoring of natural populations ofthe clam Tapes philippinarumfrom two sites in the Lagoon
of Venice was carried out together with a transplantation experiment. The sites were chosen for
their different hydrological conditions and pollution levels. Several physiological and histochemical stress-related parameters have been measured. Clearance rate and scope for growth
are significantly affected by higher anthropogenic contamination levels acting on natural clam
bedst though they are not responsive in transplanted animals after a six-week exposure. On the
contrary "survival in air" response and lysosomal latency time are confirmed as early warning
indices, particularly suitable for both monitoring approaches. Clam T. phifippinarum is proposed
as an indicator species in order to obtain an integrated biological evaluation of coastal seawater
and sediment quality.
Introduction
Bivalve molluscs are commonly used as indicator
organisms in evaluating the environmental quality of marine coastal ecosystems, mostly for their
sessile and ftlter-feeding habits (Goldberg et al.
1978). Two different approaches have been followed, naDIely: (l) measuring the bioaccumulation of organic and inorganic chemical contaminants in target organs or in whole tissues (evaluation of the contaminant body burden); (2)
quantifying biological responses to environmental stress (evaluation of biomarkers of exposure).
Monitoring programmes can be carried out on
both native and transplanted populations, the
latter technique being based on the comparison
of chemical and/or biological characteristics in
samples collected from one population and
exposed, after translocation, to different environmental conditions. The advantages of experimental exposure through translocation experiments are based on the possibility to expose
organisms with common life history and genetic
make up at sites to be monitored at investigators'
choice (de Kock and Kramer 1994).
In the present studies, several physiological
and histochemical stress-related parameters
have been monitored in two natural populations
of the clam Tapes philippinarum and after a
transplantation experiment at the same locations
in the Lagoon of Venice.
The sampling sites were chosen on the basis
of their organic and trace metal contaminants
level, reflecting different anthropogenic impact
(Martin et ala 1994; Fattore et ala 1997a, 1997b;
Frignani et ala 1997).
Materials and Methods
Two natural populations of T. philippinarum, one
from a polluted industrial area, Porto Marghera,
and the second one from a relatively clean site
though featuring highly variable hydrologic
parameters, like temperature, salinity and dissolved oxygen, Palude della Rosa (Bianchi et al.
1997), were monitored twice a year. Moreover, a
transplantation experiment was carried out on
organisms taken from a reference commercial
growing area (Val Dog!) and translocated for six
weeks at the SaDIe monitoring sites. Samplings
on natural populations were performed in April
and July, and the transplantation experiment in
April. 1998. While SaDIpling the dams, the water
1 Dipartimento ill Biologia, Universita ill Padova, Via G. Colombo 3,35121 Padova. Italy
z Istituto di Biologia Marina, CNR, Castello 13641A. 30122 Venezia, Italy
F.M. Faranda, L Guglielmo, G. Sperle (eds)
Mediterranean Ecosystems: Structures and Processes
@ Springer-Verlag ltalia 2001