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CADDIS Volume 1

Figures: Spatial/Temporal Co-occurrence

Figure 3-1a. Spatial/Temporal Co-occurrence with Upstream/Downstream Comparisons, Supports

The impairment (dead fish) occurs downstream of the source of the causal agent (effluent) but not upstream supports this case.

                     Figure 3-1a illustrates how upstream the fish are fine, but downstream where there is an impairment, the fish are dying.Figure 3-1a. Spatial/Temporal Co-occurrence with upstream/downstream comparisons illustrate how this supports the case.
 

Figure 3-1b. Spatial/Temporal Co-occurrence with Upstream/Downstream Comparisons, Weakens

The impairment (dead fish) occurs both upstream and downstream of the source of the causal agent (effluent) weakens this case.

Figure 3-1b illustrates how the impairmentis may not be the cause, if healthy and dead fish exist both up and downstream.Figure 3-1b. Spatial/Temporal Co-occurrence with Upstream/Downstream Comparisons, Refutes

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Additional Illustrations of Spatial/Temporal Co-occurrence are included below:

Figure 3-2a. Spatial/Temporal Co-occurrence with Positive Reference Sites, Supports

The impairment (dead fish) occurs in similar ecosystems exposed to the same causal agent (effluent from the same industry) at another site.

Figure 3-2a. When comparing a positive reference site to an impaired site, this illustrations shows that dead fish may occur in both locations when exposed to the same impairment.Figure 3-2a. Spatial/Temporal Co-occurrence with Positive Reference Sites, Supports the Case
 

Figure 3-2b. Spatial/Temporal Co-occurrence with Positive Reference Sites, Weakens

The impairment (dead fish) does not occur in similar ecosystems exposed to the same causal agent (effluent from the same industry) at another site.

Figure 3-2b. When comparing a positive reference site to an impaired site, this illustrations showed that dead fish only occured in the impaired site when exposed to the same impairment.Figure 3-2b. Spatial/Temporal Co-occurrence with Positive Reference Sites, Weakens the Case
 

Figure 3-3a. Spatial/Temporal Co-occurrence Through Time at a Site, Supports

The impairment (dead fish) occurs when the causal agent occurs (the effluent is being discharged) but not when it does not occur (no discharge).

Figure 3-3a. shows how over time, there are dead fish when the impairment is released but not when it is not.Figure 3-3a. Spatial/Temporal Co-occurrence Through Time at a Site, Supports the Case

Figure 3-3b. Spatial/Temporal Co-occurrence Through Time at a Site, Weakens

The impairment (dead fish) occurs whether the causal agent occurs (the effluent is being discharged) or not (no discharge).

Figure 3-3b. shows how over time, there are dead fish when the impairment is released and when it is not.Figure 3-3b. Spatial/Temporal Co-occurrence Through Time at a Site, Weakens the Case

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Explanation of the Types of Evidence Illustrations

This description applies to each of the types of evidence illustrations. These illustrations provide graphic explanations of the types of evidence. They are somewhat abstract to convey that they are representative of the concept rather than illustrations of particular applications. The live fish (green and upright) represent unimpaired organisms, populations or communities of all types, not just fish. The dead fish (white and belly-up at the surface) represent all biological impairments, not just dead fish. The pipe represents all sources and the yellow effluent plume represents all causal agents (stressors), not just effluents or even chemicals. Clock faces represent the passage of time, not the particular time difference illustrated. Fish in beakers represent laboratory tests. Other graphic elements used in particular illustrations are explained in the caption.

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