Transcript No Slide Title

Ecological vulnerability of macroinvertebrates, comparing
sensitivity to vulnerability for chlorpyrifos
H.J. De Lange, R.P.A. Van Wijngaarden, G.H.P. Arts
Introduction
The Ecological Vulnerability Analysis [1] uses species traits of
wildlife species to estimate likelihood of exposure to a
contaminant and potential recovery mechanisms. For the set of
wildlife species used in the original analysis toxicity data were
not available to include in the analysis. However, for aquatic
macroinvertebrates toxicological sensitivity data for chlorpyrifos
are available. We therefore compared the sensitivity data [2, 3]
to calculated vulnerability scores for a selection of aquatic
macroinvertebrates.
Table 1: Traits used, methodology according to [1]
Category
A: external exposure
Increasing or
decreasing
Weight
effect on
factor vulnerability
Trait
habitat preference
0.258
+
max life span
0.032
+
home range
0.129
-
food preference
0.129
+
daily food needs
0.065
+
hibernation
B: internal exposure
0
-
season-dependent presence
0.258
+
home range < distribution contaminant
0.129
+
field metabolic rate
0.364
-
hibernation
0
+
season-dependent presence
0
-
Methodology
storage organs
0.091
-
excretion organs
0.182
-
For 19 freshwater invertebrate species ecological traits were
collected (Table 1). These were available from an Alterra
database, added with literature values. Two vulnerabilty scores
were calculated:
1) Without toxicity, category A, B and D each weighed 0.333
2) Including toxicity, category A, B, C, and D each weighed 0.25
detoxifcation mechanisms
0.364
-
C: effects on individual level LC50
D: population recovery
age at first reproduction
lifetime reproduction
survival to first reproduction
dispersal capacity
living area patchy or dense
territorial behaviour
1
-
0.176
0.176
0.176
0.294
0.118
0.059
+
+
+
+
Results
Comparing vulnerability 1 (without tox) with LC50 there’s no
relation (Fig. 1), suggesting that exposure and recovery are
independent of toxicological sensitivity. Ablabesmyia is the most
vulnerable, and Gammarus the least.
Showing the 4 categories including toxicological sensitivity (Fig.
2) illustrates the differences between species. The two
gastropod species are the least vulnerable in this comparison,
due to their very low sensitivity. Ablabesmyia is again the most
vulnerable species.
chlorpyrifos vulnerability without tox
0.65
0.60
Ablabesmyia
Simocephalus
Plea
Daphnia Chaoborus Ceriodaphnia
Sialis
Paraponyx
0.55
0.50
Asellus
Caenis
Cloeon
0.45
Proasellus
Bithynia
Lymnaea
Mystacides
Corixa
0.40
Notonecta
Anax
Gammarus
0.35
0.30
0.1
Discussion
10
100
0.8
chlorpyrifos vulnerability including tox
The methodology applied was identical to [1]. Vulnerability
scores without toxicity (Fig. 1) can be directly compared with the
wildlife vulnerability scores. Species in the upper left quadrant
combine high vulnerability (by exposure and lack of recovery)
and high sensitivity.
Including toxicity in the vulnerability score (Fig. 2) gives a
potential indication of field effects. This needs further
confirmation.
The method can be further improved specificly for aquatic
invertebrates by including more aquatic habitat types, and by
including traits specifying mode of respiration.
1
chlorpyrifos LC50 (g l-1)
Figure 1: Sensitivity (LC50) versus vulnerability
without toxicity.
external exposure
internal exposure
tox sensitivity
population recovery
0.6
0.4
0.2
Bithynia
Lymnaea
Anax
Gammarus
Corixa
Notonecta
Proasellus
Mystacides
Caenis
Cloeon
Asellus
Sialis
Paraponyx
Plea
Ceriodaphnia
Daphnia
Simocephalus
Chaoborus
References
[1] De Lange et al. 2009, ET&C, 28, 2233-2240
[2] Van Wijngaarden et al. 1996, ET&C,15, 1133-1142
[3] Rubach et al. 2011, Arch Env Contam Toxicol, 60, 708-721
Ablabesmyia
0.0
Figure 2: Vulnerability score including toxicity
broken down into the 4 categories
Alterra, Wageningen UR, PO Box 47, 6700 AA Wageningen, The Netherlands
For more information contact Marieke De Lange: E-mail: [email protected] ; Phone: +31-317-485784; Fax: +31-317-419000