| ||||||||||||||||||||||||||||||
|
||||||||||||||||||||||||||||||
| Copyright © 2009. National Academy of Sciences. All rights reserved. Terms of Use and Privacy Statement |
Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 97
5
A Framework for the
Analysis of Monitoring
The previous chapter documented the wide range of monitoring pro-
grams being carried out in the Southern California Bight. Because these
programs can be evaluated from many different perspectives, it is important
to clarify the criteria the panel used in its analysis of monitoring efforts.
These criteria summarize the conceptual framework developed by the par-
ent committee. They provide the basis for determining whether individual
programs, as well as the monitoring system as a whole, are effective or not,
and can be expressed as six questions:
1. Does monitoring address clearly stated management and societal
objectives?
2. Does monitoring address the major environmental problems facing
the bight?
3. Do the spatial and temporal scales of monitoring reflect those of
the major environmental problems?
4. Are the technical design and implementation of monitoring of high
quality? This includes proper statistical design of sampling and analysis,
use of state-of-the art field and laboratory techniques, and adequate links
to relevant research programs.
5. Do monitoring programs respond in a timely way to changing
conditions and needs?
6. Are monitoring resources allocated effectively both within and
among monitoring programs?
These criteria reflect the literature on monitoring (e.g., Holling, 1978;
97
OCR for page 98
98
Green, 1979; Beanlands and Duinker, 1983; Fritz et al., 1980, National
Research Council, 1986; Isom, 1986; Rosenberg et al., 1981; and Bernstein
and Zalinski, 1983, 1986) and the experience of the panel members.
It is important to recognize that issues addressed by the evaluation
criteria are not strictly technical. This is because monitoring is defined
by and carried out within a complex context that includes the interests
and information needs of the public and the regulatory agencies and the
requirements (procedural and otherwise) of relevant laws and permits, as
well as strictly scientific and technical concerns. The analysis of monitoring
must therefore look as much at the interface between policy and technical
issues as at the technical issues themselves.
The following sections address three areas that are especially relevant
to the analysis of monitoring and that underlie the evaluation criteria:
.
the importance of clear objectives,
· the role of technical design and its statistical component, and
· the necessity for identifying, evaluating, and prioritizing environ-
mental problems.
THE IMPORTANCE OF OBJECTIVES
Monitoring programs are intended to produce information for quan-
tifying and evaluating the effects of human activity on the marine en-
vironment. Monitoring is intended to provide decision makers with the
information they need to make appropriate management decisions about
how to protect the marine environment and its resources. Ideally, these
information needs should be expressed as objectives that guide the design
and implementation of monitoring programs.
The objectives that currently motivate monitoring programs in the bight
can be loosely structured as a hierarchy. At the highest level are broad
concerns about human health and the status of the ecosystem. Beanlands
and Duinker (1983) make the point that objectives at this level often
reflect sociopolitical values that cannot always be quantified or supported
scientifically. This, however, does not necessarily lessen their importance
or relevance as the basis of management and monitoring efforts. At the
next level are the laws and regulations that embody these concerns as
more specific objectives or requirements. At the next level are permits
for individual discharges or other activities, which in some cases contain
numerical monitoring criteria. Finally, the monitoring design itself is based
on decisions about what, specifically, to measure, when, where, and how
often to measure it, and about what degree of uncertainty in the final
answer is acceptable. Ideally, each level should incorporate the content and
intent of the preceding level. Westman (1985) has described an analogous
OCR for page 99
99
hierarchy in terms of successively more specific and detailed goals, policies,
strategies, and tactics.
As the foregoing discussion implies, clear objectives are crucial for both
the monitoring and decision-making aspects of environmental management.
For monitoring practitioners, they direct monitoring efforts toward the
measurement of specific parameters and of specific amounts and rates of
change. Without such clear objectives, it is impossible to effectively use
such technical design tools as conceptual, numencal, and statistical models,
and power and optimization analyses. For managers and regulators, they
provide a standard against which environmental change can be measured in
order to determine if corrective action is required. It is therefore necessary
to completely specie objectives at each level of the hierarchy, from broad
public concerns to specific, numerical criteria.
THE ROLE OF TECHNICAL DESIGN
Technical design involves making decisions about what to monitor;
how, when, and where to take measurements; and how to analyze and in-
terpret the resulting data. The parent Committee on a Systems Assessment
of Marine Environmental Monitoring developed a design methodology that
the panel used to structure its evaluation of this aspect of monitoring in the
Southern California Bight (Figures 5-1 to 5-4) (National Research Coun-
cil, 1990~. Figure 5-1 shows that technical design must be considered in
relation to the initial definition of goals and objectives and the ultimate
effective dissemination of monitoring information. Figures 5-2 to 5-4 pro-
vide additional detail about the relationships among specific elements of
the methodology.
The methodology summarized in Figures 5-1 to 5-4 reflects definite concepts
about effective monitoring design and its benefits. These concepts are not
the only ones that could have been used to structure an evaluation of the
technical design of monitoring programs. They do, however, reflect many
of the important themes that recur in the literature on monitoring design.
The following is a summary of these concepts:
.
Appropriate technical design ensures that data collection, analysis,
and interpretation will address management needs and objectives. oTech-
nical design can be performed adequately only when objectives, problems,
questions, or hypotheses are stated explicitly.
· Sampling, measurement, and analysis designs should be developed
with the goal of detecting specific kinds and amounts of change.
· Predictions about the kinds and amounts of change expected should
be derived from conceptual models that specify how particular human
activities (causes) will lead to environmental impacts (effects).
OCR for page 100
100
Refine
Objectives
l
Step 1
_ Define
Expectations and Goals
Step 2
Define
l Study Strategy
Reframe
Questions
i ~
No
Rethink
Monitoring
Approach
Step 4
Develop
Sampling Design
Be Det~:t~?
~( Yes
, Step 5
Implement Study
1 1
~ 1
1
Step 6
Produce Information
No ~ Is Information \
Adequate?
Yes
Step 7
Disseminate Information
Make Decisions
Burr N;;~
\ Conduct Exploratory
§ Studies if Needed
FIGURE 5-1 The elements of designing and implementing a monitoring program.
· Sampling and measurement designs should account for important
sources of natural variability.
· Sampling and measurement designs should be evaluated before-
hand to determine their ability to detect predicted changes.
· Analysis approaches should be selected before data collection to
correspond to the statistical assumptions of the sampling design.
· Data base systems should make authorized versions of the data
readily available to analysts and managers, and should provide easy access
to a wide range of analysis, graphics, and reporting tools.
OCR for page 101
101
Identify Public Identify Relevant
Concerns and Laws, Regulations, and
Expectations Permits
' ~' ' 1 '
.
_ ,_
Focus Scientific
Understanding
1 1
1t
Establish
Environmental and Human
Health Objectives
FIGURE 5-2 Step 1: Defining expectations and goals of monitonng.
The technical design process illustrated in Figures 5-1 to 5-4 furnishes
a framework for translating broad questions and objectives into specific
decisions about what to measure, where to measure it, and how many
measurements to take. Using this framework as an evaluation tool enabled
the panel to use a common set of standards in considering the technical
design of monitoring programs in the bight.
OCR for page 102
102
Identify Resources
at Risk
| Modify
Resources
No
~ Yes
| Determine l
| Appropriate Boundaries l
I'
Boundaries
Adequate? /
~ Yes
Predict Responses
and/or Changes
Are \ No
- Predictions ~
~ Yes
Develop
Testable Questions
FIGURE 5-3 Step 2: Defining study strategy.
~ Develop Con eptual Model
~ 1
/Have Appropriate \ | Adjust l
Resources Been ~Boundaries
Selected? ~
A FRAMEWORK FOR PRIORITIZING PROBLEMS
Refine
Model
As stated previously, this case study is oriented toward examining
the monitoring system in the bight as a whole. In addition to evaluating
whether individual programs meet their objectives, this necessitates de-
termining whether the entire collection of monitoring programs produces
OCR for page 103
103
Develop Testable
Questions
Identify Meaningful
Levels of Changes
i ~' 1
Select What
to Measure
Reframe I .
Questions
~ _
_ ~I
Develop
Monitoring Design
~I
| Specify
Statistical Models
l No /n Predict
Responses Be Seen'
~ Yes
Rig fine ~
Technical Define Data
Design Quality Objectives
T
Identify Logistical
Constraints
, Conduct Power Tests
' and Optimizations
r
.1
Develop
Sampling Design
No /s Design
~ Adequate?
-
~~~ Yes
FIGURE 54 Step 3: Developing sampling and measurement design.
the information needed to satisfy both management and the public. The
technical design methodology described above provided a means of struc-
turing the analysis of individual programs. However, there was no similar
framework available for the overall analysis of the monitoring system. The
panel therefore adapted existing methods in order to perform a summary
assessment of environmental impacts on resources in the bight. This as-
sessment was intended to summarize the nature and severity of impacts on
OCR for page 104
104
a range of important resources in the bight and was designed to help the
panel address specific questions.
· Does monitoring address clearly stated management and societal
objectives?
· Does monitoring address the major environmental problems facing
the bight?
Do the spatial and temporal scales of monitoring reflect those of
the major environmental problems?
· Are monitoring resources allocated effectively both within and
among monitoring programs?
The Assessment Framework
While many useful frameworks have been proposed for environmental
assessments (see examples in Beanlands and Duinker, 1983; Westman,
1985; NRC, 1986), constructing one for monitoring in the bight in the
context of the case study presented special difficulties. First, the goal
of the assessment was to produce a synthetic overview that would aid in
drawing conclusions about the entire monitoring system in the bight, both
technical and institutional. This is in contrast to more typical assessments
that focus only on identifying and quantifying the environmental impacts of
individual projects. Second, the time available for developing this overview
was necessarily short and the technical and financial resources available
were limited. Third, there are extensive and diverse human and natural
sources of perturbation in the bight and methods for characterizing multiple
and cumulative impacts are not well developed. For example, effects on
fish populations may derive from:
· coastal power plants~ntrainment of larvae, impingement of adults;
municipal wastewater outfalls-habitat alteration, changes in food
supply, contamination;
· dredged material disposal-habitat alteration, contamination;
· storm runoff-contamination; and
· sport and commercial fishing-increased mortality.
· E1 Ninos~hanges in distribution and community structure' habitat
alterations; and
· major storms-habitat alteration.
Such effects act on different spatial and temporal scales, and this adds to
the challenge of understanding and portraying impacts.
~ accommodate these constraints and difficulties, the panel used a
combination of matrix and ad hoc assessment methods (Westman, 1985.
~ The matrix approach was adapted from a framework developed by Clark (1986) for identifying
OCR for page 105
105
The assessment produced synoptic overviews that were useful in evaluating
the overall pattern of monitoring in the bight. However, before reviewing
the assessment products and explaining the supporting detail, it is important
to understand the limitations of the matrix and ad hoc methods used. In
most cases, the limitations of each method were somewhat balanced by the
strengths of the other. The procedure described by Clark (1986) proceeds
through a series of steps that specify:
valued ecosystem components (VECs),
· marine constituents (both natural ecosystem parameters and an-
thropogenic contaminants) that cause changes in the VECs, and
· sources of natural and human-induced perturbation that create or
cause changes in these constituents, which are linked in a matrix with
specific VECs to show how they along with contamination in the bight
affect marine resources (Figure 5-5~.
The selection of perturbations, constituents, and VECs is necessarily
somewhat arbitrary. Given the size of the bight and the multiplicity of
resources and sources of impact, some selection among these was unavoid-
able. This selection reflects the values and biases of the panel, but the
critical reviews by experts and scientists outside the panel were designed
to balance competing points of view. However, there is no denying that
other reviewers might have generated parameters that would have led to a
different assessment.
The matrices do not specifically identify primary, secondary, and higher
order interactions among perturbations, constituents, and VECs. This
would be a severe shortcoming if the matrices were used as a stand-alone
assessment method. In this case, however, the matrices were used as a
cross check for the conclusions derived from the ad hoc approach and to
enforce a degree of systematic thinking. While the matrices themselves do
not specify interactions, they were discussed at length during preparation
of the matrices and as part of the ad hoc approach.
The matrix products do not quantity effects and impacts. Rather
Figure 5-5 scales two impact attributes, the potential influence of each
source of perturbation and the degree of scientific certainty associated
with this conclusion. This is similar to the scaling of impact magnitude
and importance proposed by Leopold et al. (1971) in a similar matrix.
This subjective scaling would be a major shortcoming if the panel's intent
was to perform a damage assessment, a detailed project assessment, or a
comparison of two or more alternative development scenanos. However, in
cumulative impacts. The ad hoc portion of the assessment (Rau and Woolen, 1980) consisted
of brainstorming sessions with experts and critical review of the matrix products by individual
scientists. The matrix products were modified a number of times to incorporate feedback from
brainstorming sessions and individuals' reviews.
OCR for page 106
106
VALUED ECOSYSTEM
COMPONENTS
SOURCES \
OF PERTURBATION \
00
a)
AC ~CO 1/ 0) ~=
Storms
~ ~0 ~
El Ninos
~0~ ? ~ ~ ~
Upwelling
~ O ~ ? ~
Basin Flushing
Mass Sediment Flows
O O Elm
Blooms/lnvasions
Diseases
of
?
Ecological Interactions
Q~ ~ ? ~
Power Plants
HE ~
~ ?
Wastewater
Outfalls
~ O
Dredging
River Flow and Storm
water Runoff
~ ?
O ~ ~ O 0~
Commercial Fishing
Sport Fishing
o To
loo To
? ? 0
Marine Commerce and
Boating
Habitat Loss and
Modification
Oil Spills
Oil Seeps
Atmospheric Input
POTENTIAL INFLUENCE
E| Controlling ~ Major E] Moderate ~: Some
? - Some evidence for impact but further study needed
Blank - no impact
ASSESSMENT RELIABILITY
FIGURE 5-5 Impacts on the marine environment of the Southern California Bight.
Individual cells of the matrix illustrate the presumed relative impact of each source on
each component, along with the associated scientific certainty. Each column represents
cumulative impacts on individual components; each row shows the effects of individual
perturbations on all components. This figure was used to summarize and investigate ways
of identifying and ranking impacts in the bight. SOURCE: After Clark, 1986.
OCR for page 107
107
this case the panel's goal was to produce a high-level overview that would
assist in comparing the overall pattern of impacts with the overall pattern
and structure of monitoring programs. In addition, much of the background
information used in both the matrix and ad hoc efforts was derived from
extensive and quantitative research, monitoring, and modeling programs.
The overviews that resulted from the assessment lack detail about the
nature of the effects they represent. Again, this is less of a problem given
the panel's task In fact, the high-level, summary character of the overviews
was actually helpful in elucidating the weaknesses of the existing monitoring
structure.
The ad hoc method depends on the collected experience and insights
of the participants. As a result, conclusions are dependent not only on
the selection of participants but also on their values and biases. Under
the circumstances, the panel believed that enlisting the participation of
a cross section of scientists from the bight region was the most efficient
means of integrating the wealth of scientific and technical information
available. Involving scientists of differing affiliations helped to balance
individual values and biases. In addition, the matrix method helped to
focus, systematize, and cross check each person's opinions and judgments.
No assessment method is perfectly objective. While quantitative mod-
els are increasingly valuable, even they depend on certain simplifying as-
sumptions and often are challenged. Similarly, even a moderately sized
monitoring program must make judgments about which aspects of the envi-
ronment to measure or ignore, since it is impossible to measure everything.
The panel used the assessment products to derive conclusions about the
structure and focus of the monitoring system in the bight. The conclusions
were judged to be robust enough to form the basis for conclusions and
recommendations, even in light of the acknowledged limitations of the
assessment methods used.
A Synoptic Overview
The matrix in Figure 5-5 is a useful heuristic tool. It shows that all
ecosystem components are impacted by more than one kind of perturbation.
It also shows that perturbations typically affect more than one ecosystem
component. For example, storms affect soft benthos, kelp beds, and human
health; wastewater outfalls affect soft benthos, microheterotrophs, and
demersal fish populations.
Figure 5-5 helps categorize the types of monitoring programs in the
bight. Some programs examine the effects of one perturbation on a single
resource. These programs focus on one cell of Figure 5-5 and are called
single-cell assessments. For example, the impingement sampling program
carried out by the Southern California Edison Company is intended to
OCR for page 108
108
assess the potential impacts of coastal power plants on pelagic fish popula-
tions. Other monitoring programs examine the effects of one perturbation
on a range of resources. These programs focus on an entire row of Figure
5-5 and are called row assessments. For example, the 301(h) monitoring
program around the Orange County wastewater outfall is designed to doc-
ument the effects of the outfall on a range of resources, including soft
benthos, water quality, and demersal fish populations. Monitoring pro-
grams that consider how several perturbations, acting together, affect a
single resource would focus on an entire column of Figure 5-5 and are
called column assessments. There are no examples of such programs in the
bight, a fact which will be addressed in more detail in Chapter 6. Further,
there are no coordinated monitoring programs in the bight that focus on
the effects of two or more sources of perturbation on a range of related
resources. Such a program, for example, might document the combined
effects of fishing, power plants, and wastewater outfalls on demersal and
pelagic fish populations.
Figure 5-5 also presents subjective judgments about the relative im-
portance and degree of scientific certainty associated with each impact. For
example, wastewater outfall impacts on soft benthos are more severe and
extensive than those from dredging. As another example, it also shows that
conclusions about kelp bed impacts are probably more reliable than those
about effects on fish eggs and larvae. Such comparisons aid in analyzing
existing monitoring programs by suggesting where further research would
be more appropriate and useful than routine monitoring. As Chapter 6
makes clear, available financial and technical resources in the bight are
not systematically allocated to research and monitoring on the basis of a
comprehensive overview like the one in Figure 5-5.
As with Figure 5-5, Figure 5-6 is a useful heuristic tool that supplies
insights about the structure of existing monitoring programs in the bight. It
shows quite clearly that the impacts that are relatively well understood (e.g.,
coastal power plant plumes, disposal of marse dredged material, nutrients,
fine particles) are those whose scales are either less than or of the same
order of magnitude as those of monitoring programs. It also demonstrates
that, with the exception of the CalCOFI program, the temporal and spatial
scales of individual monitoring programs are insufficient to resolve patterns
of effects on larger scales. While the effects of scale are becoming a
matter of concern to ecologists (Wiens, 1989), Figure 5-6 demonstrates
that monitoring programs in the bight are not consistently designed with
such scale effects in mind. As Wiens (1989) points out, these effects can
be complex, and-if not considered carefully ". . . we may think we
understand the system when we have not even observed it correctly."
OCR for page 109
109
Supporting Detail
As the first step in the matrix assessment procedure, the effects of
the constituents on the VECs are identified (Figure 5-7), and the ways
in which sources of perturbation cause changes in these constituents are
then specified (Figure 5-8~. This permits sources of perturbation to be
linked (through changes in the constituents) directly to effects on VECs
in a matrix (Figure 5-5~. This in turn allowed the panel to summarize the
effects of various human and natural processes on the VECs. Finally, the
temporal and spatial scales of constituents and perturbations (Figure 5-6)
are compared to the spatial and temporal scales of relevant monitoring
programs.
Figure 5-7 qualitatively shows the effects of changes in marine con-
stituents on valued marine ecosystem components. VECs include important
ecosystem components and major fisheries, as well as demersal and pelagic
fish life stages that occupy distinct habitats and might be affected differ-
entially. Constituents are divided into physical oceanographic parameters
(e.g., waves or temperature), and into Boating, dissolved, suspended, and
settleable categories. Figure 5-7 shows that specific constituents impact
more than one VEC and that some VECs are affected by more than one
constituent.
The constituents shown in Figure 5-7 were selected because they are
typically measured in monitoring programs. Their division into floating,
dissolved, suspended, and settleable categories reflects the fact that their
association with particles of different sizes significantly influences the fates
and effects of most contaminants. However, the selection and arrangement
of these constituents is certainly not the only one possible. For example,
rather than focusing on physical and chemical parameters, the constituents
could include important dynamic processes, such as production, nutrient
regeneration, the flux of organic matter, and recruitment and mortality.
Figure 5-8 furnishes the next link in the matrix-based assessment by
showing which sources of pertur~afion affect which constituents. This then
permits connecting sources of perturbation to effects on VECs. For exam-
ple, the amount and distribution of fine particles and nutrients are affected
by wastewater outfalls (Figure 5-8), and such changes can potentially affect
the soft benthos (Figure 5-7~. This suggests a potential mechanistic link
between wastewater outfalls and effects on the soft benthos. Similarly,
marine commerce and boating create floating debris (Figure 5-8), which af-
fects marine birds (Figure 5-7~. (These admittedly simplistic examples were
chosen for illustrative purposes; the reader is encouraged to investigate
other links suggested by Figures 5-7 and 5-8~.
These two figures can be integrated to furnish a synoptic view of the
impacts of both natural and human perturbations on the VECs. Thus, one
OCR for page 110
110
Hour Day Week tAonth
Year Decade Century
3
2
E
y
o
- 1
~:
~n
o
_- x _
~NONMOBILE
TEMPERATURE
\
_- _ ~
CURRENTS
DISSOL\/ED OXYGEN
PATHOGENS* I ~
FINE PARTICLES
NUTRIENTS
POLAR ORGANICS ~
1
PATHOGENS /
/ ~
I TEMPERATURE*
I COARSE PARTICLES
I ORGANOMETALLICS
~ \lOlATILE ORGANICS
_ _ __
METALS
HYDROPHOBIC
ORGANICS
COMPLEXED
_ - METALS
4 3 -2
UJ
LL
i~ ~
LL
-. 0 1 2 3
TIME (log YEAR)
x Power Plants
x Outfalls
x Harbors/Marinas
| Fishing
I Dredging
I Peak River Flow
I I Storms
I I EI Ninos
I I Blooms
I I Diseases
I I Ecological Interactions
1 000 km
100 km
10 km
1 km
100 m
OCR for page 111
111
cO
a'
.-
co
a)
a)
~5 c'd) cl7
c) ct ~
- -
T°¢
1
-!
in
I
In
In
s ~
`,, Q
> as
I
. .
CD
o
-
c)
a,
=
c)
._
a)
o
o
C>
LL
-
cn
i m0
_ .
Z
111
Z LL
tar: ~
En LLI
~ m
J
co 0
FIGURE 5-6 Characteristic temporal and spatial scales of important constituents and
sources of perturbation. Constituents are the same as those in Figure 5-6, but have been
abbreviated. "Temp *" refers to temperature changes from coastal power plants, and
"Temp" to natural temperature changes (i.e., El Nino events). "Path *" refers to bacterial
contamination from wastewater outfalls and storm runoff, and "Path" to pathogens from
natural sources that cause diseases in urchins, fish, and other organisms. The abscissa
represents a crude estimate of the half life or recurrence time of each constituent. The
ordinate represents the spatial displacement likely to occur over that time, or the scale of
activity. For example, nonmobile metals and hydrophobic organics are presumed to persist
in the environment and spread much more widely than nutrients. The temporal and spatial
boundaries of existing monitoring programs are outlined by a solid line, with the exception
of the CalCOFI Program, whose parametem are indicated by an "X" in the upper right of
the figure. Constituents with similar temporal and spatial scales are outlined with dotted
lines. SOURCE: After Clark, 1986.
OCR for page 112
OCR for page 114
OCR for page 115
Representative terms from entire chapter:
technical design
112
\
MARINE
CONSTITU ENTS
\ VALUED ECOSYSTEM
co
Q
o C
_ o
o y
_ C
_ ~
~Q
o o
s
C
o
~o
C _
ca 0
4 Q
o
o o
N cry
(n
o
s
m
0 ~
_ 13
C5 Q
-
a,
. _
o, -
U) s
In
{C At
13 a)
C ~
V
a,
J`45
E
E
CO~
o) ~
IL0>
sa:
Inm:
._~
~C
c
.m
~-
a>
113
can start with VECs such as soft benthos or demersal fish populations,
identify the constituents that affect them, and then trace these constituents
back through their relationships with sources of perturbation to finally
determine all the kinds of perturbations that affect these ecosystem compo-
nents. The result of this process can be displayed as a matrix (Figure 5-5)
that summarizes the impact of each kind of perturbation on each ecosystem
component.
Figure 5-5 was constructed using other knowledge from the ad hoc
method in addition to the mechanistic linkages shown in Figures 5-7 and
5-8. This points up shortcomings in the selection and organization of the
constituents shown in Figure 5-7. For example, Figure 5-5 shows that
sport and commercial fishing impact pelagic and demersal fish by directly
removing individuals from the population. However, since Figure 5-8 does
not include mortality as one of the marine constituents, Figures 5-7 and 5-8
do not combine to predict impacts on fish from fishing, an obvious failing. In
addition, Figure 5-5 indicates that blooms, natural diseases, and especially
ecological interactions have significant effects on the VECs. However,
Figure 5-7 shows that none of these important sources of perturbation
interact strongly with any of the constituents other than temperature and
dissolved oxygen. The panel thus combined insights from both the matrix
and ad hoc methods without rigidly adhering to the limitations of either.
Figure 5-5 is an informative way to organize existing knowledge about
impacts on marine resources. However, the spatial and temporal scales of
both perturbations and ecosystem processes vary widely and this informa-
tion is necessary to evaluate the effectiveness of monitoring. The overall
assessment framework therefore includes a means of organizing and com-
paring the temporal and spatial scales of constituents and perturbations.
A preliminary approach is presented in Figure 5-6. The constituents are
placed in a logarithmic time-space coordinate system based on crude esti-
mates of their half-lives in the marine environment (for contaminants) or
their typical scale of activity (for ecosystem features). The temporal and
spatial range of existing monitoring programs is indicated, and the temporal
and spatial scales of important perturbations shown along the x and y axes,
respectively.
SUMMARY
This chapter presents the criteria and concepts used to organize the
analysis of monitoring efforts reviewed in the next chapter. Six key questions
made up the evaluation criteria used to assess both individual monitoring
programs and the collection of monitoring programs in the bight. These
questions addressed both the policy and technical aspects of monitoring,
114
\ SOURCES OF
\ PERTURBATION
MARINE
CONSTITUENTS
\
.~ c
~ _
~ ,5
~_
o ~ ~ ·'- ~ ~ ' ~ ~ ~ o- ~ ~ ~ ~ ~ ~ 6 ~
OCEANOGRAPHIC
Currents
Winds
Waves
Temperature
Dissolved Oxygen
· ·
·
·
· ~ ~·
· ~ · ·
FLOATING
Floating Debris
DISSOLVED
Nutrients
Volatile Organic$
Polar Or$ian,cs
Complexed Metals
Organometallics
·
·
·
·
SUSPENDED
Fine Particles
Coarse Particles
Nutrients
Pathogens
Hydrophobic Org&n~cs
Orgenomet~llics
Nonmobile Metals
_SETTLEA~6
Fine Particles
Coarse Particles
Nutrients
Hydrophobic Organics
Nonmobile Metals
· · · ~ ~ -
· · ~ ~ ·
· · ~ ~
· ~ ·
· · ~ ~ ~
FIGURE 5-8 Sources of major perturbations to the bight's marine ecosystem and their
major impacts on marine constituents. The dots indicate that the listed perturbation (top)
is presumed to have a significant effect on the listed constituent (left). Both direct and
indirect impacts are included. Perturbations include both human and natural sources of
change. Basin flushing refers to the turnover of near-bottom water in offshore basins; mass
sediment flows to sudden, large movements of sediment on the shelf; blooms or invasions to
rapid increases in population levels of otherwise rare species (e.g., the echiuran Lis~iolobus
or the kelp isopod Peniidothea resecta). Multiple sources of impacts of one kind (e.g.,
power plants, dredging) have been lumped to provide a consistent level of generality among
perturbations. SOURCE: After Clark, 1986.
115
emphasizing the panel's focus on the functioning of the monitoring system
as a whole.
Three areas that are especially relevant to the evaluation criteria
were also discussed. Clear objectives are crucial in providing direction for
monitoring design and implementation. An effective technical design then
translates these objectives into decisions about what to monitor; how, when,
and where to take measurements; and how to analyze and interpret the
data. Finally, an overall assessment of environmental problems in the bight
provides a framework for determining if all important questions are being
addressed and whether monitoring resources are being allocated effectively.