ix The scope of this book is to demonstrate that we do have an ecosystem theory that can be used
to describe ecosystem structure and function... An ecosystem theory is a prerequisite for wider application of ecological
sciences in environmental management because with the theory it becomes feasible to guide conservation or environmental
management. [JLJ - with an ecosystem theory it becomes possible to guide search efforts in a game, if in fact
it is true that a game position is similar to an ecosystem.]
p.1 Sustainability Development is, according to the Rio Declaration, defined as follows:
"development that meets the needs of the present without compromising the ability of future generations to meet
their own needs."
p.2 An ecosystem is according to the Millennium Report (2003) defined as "a dynamic
complex of plants, animals and microorganism communities and the nonliving environment, interacting as a functional unit.."
[JLJ - perhaps we can define a position in a game as a dynamic complex of pieces, interacting (via previously defined rules)
as a functional unit.]
p.3 Three questions are fundamental to pursue for ecosystem-based environmental management:
I: What are the underlying ecosystem properties that can explain their response
to perturbations and human interventions?
II: Are we able to formulate at least building blocks of an ecosystem theory in
the form of useful propositions about processes and properties? ...
III: Is the ecosystem theory that we can formulate to understand ecosystem
properties sufficiently developed to be able to explain ecological observations with practical application
for environmental management?
p.4 Ecosystems grow and develop... We can follow this growth and development using
holistic metrics such as power, eco-exergy, and ascendency, respectfully.
p.4 Ecosystems have complex response to disturbance - but when we understand
properties of ecosystems such as adaptation, biodiversity, resistance, and connectedness, to mention a few of the
most important properties covered in this book, we can explain and sometimes predict the responses of ecosystems to
disturbances.
p.5 We, the authors, are of the opinion that we do have an ecosystem theory today
that is ready to be applied but which also inevitably will be developed significantly during the next one to two
decades due to (hopefully) its wider application.
p.51 What happens in the biosphere, the story of life, depends on the biosphere
constraints. Hence it is important to have global models of the biosphere in terms of space, time,
matter, energy, entropy, information, and their respective relations.
p.51 The essence of the living organism resides in it being a "configuration of processes."
p.57 we may find some satisfaction in the world of propensities. We may not know exactly what happens,
but approximately what happens.
p.69 Box 4.1 details the derivation of a measure called the System Ascendency, which quantifies
both the total activity of the system as well as the degree of overall constraint extant in the system network... In his seminal
paper, "The strategy of ecosystem development", Eugene Odum (1969) identified 24 attributes that characterize more mature
ecosystems that indicate the direction of ecological succession. These can be grouped into categories labeled species richness,
dietary specificity, recycling, and containment. All other things being equal, a rise in any of these four attributes also
serves to augment the system ascendency... It follows as a phenomenological principle "in the absence of major perturbations,
ecosystems have a propensity to increase in ascendency." This statement can be rephrased to read that ecosystems exhibit
a preferred direction during development: that of increasing ascendency.
p.71 Another way of looking [at] such "pruning" is to consider that constraints cause certain flow
events to occur more frequently than others.
p.74 Hence, increasing ascendency is only half of our dynamical story. Ascendency accounts for how efficiently
and coherently the system processes medium. Using the same mathematics as employed above, however, it is also shown in Box
4.1 how one can compute as well an index called system overhead, F, that is complementary to the
ascendency and captures how much flexibility the system retains (Ulanowicz and Norden, 1990).
The flexibilities quantified by overhead are manifested as the inefficiencies, incoherencies,
and functional redundancies present in the system. Although these later properties may encumber overall system performance
at processing medium, we saw in Chapter 3 how they become absolutely essential to system survival whenever the system
incurs a novel perturbation. At such time, the overhead comes to represent the repertoire of potential tactics
from which the system can draw to adapt to the circumstances. Without sufficient overhead, a system is unable
to create an effective response to the exigencies of its environment. The configurations we observe in nature, therefore,
appear to be the results of a dynamic tension between two antagonistic tendencies (ascendency vs. overhead; Ulanowicz, 2006b).
The ecosystem needs this tension in order to persist. Should either direction in the transaction atrophy,
the system will become fragile either to external perturbations (low overhead) or internal disorder (low ascendency).
p.79 The web of life is an appropriate metaphor for living systems, whether they are ecological,
anthropological, sociological, or some integrated combination - as most on Earth now are. The phrase immediately conjures
up the image of interactions and connectedness both proximate and distal: a complex network of interacting parts,
each playing off one another, providing constraints and opportunities for future behavior, where the whole is greater than
the sum of the parts... Networks: ... the current focus on biodiversity, stability, and sustainability, which all use networks
and network concepts to some extent. It is appropriate that interconnected systems are viewed as networks because of the powerful
exploratory advantage one has when employing the tools of network analysis: graph theory, matrix algebra, and simulation modeling,
to name a few.
Networks are comprised of a set of objects with direct transaction (couplings) between these
objects... these transactions viewed in total link direct and indirect parts together in an interconnected web, giving
rise to the network structure... The connectivity of nature has important impacts on both the objects within
the network and our attempts to understand it. If we ignore the web and look at individual unconnected organisms... we miss
the system-level effects.
p.81 Each component, in fact, must be connected to others through both its input and output transactions.
There are no trivial, isolated components in an ecosystem.
p.84 If the environment is organized and can be viewed as networks of ordered and functioning systems,
then it is necessary that we have analysis tools and investigative methodologies that capture this wholeness. Just
as one cannot see statistical relationships by visually observing an ecosystem or a mesocosm experiment, one must
collect data on the local interactions that can be estimated or measured, then analyze the connectivity and properties that
arise from this. In that sense, systems analysis is a tool, similar to statistical analysis, but
one that allows the identification of holistic, global properties of organization.
p.84 System behavior frequently arises out of indirect interactions that are difficult to incorporate
into connected mental models. Many societal problems, which may be environmental, economic, or political,
stem from the lack of a systems perspective that goes to remote, primary causes rather than stopping at proximate,
derivative ones.
p.111 The concept of ecological indicators has been introduced ~ 15-20 years ago. These
metrics indicate the ecosystem condition or the ecosystem health, and are widely used to understand ecosystem dynamics
in an environmental management context.
p.112 Definitions of orientors, indicators, and goal functions
Ecological orientors: Ecosystem variables that describe the range of directions in which
ecosystems have a propensity to develop. The word orientors is used to indicate that we cannot give complete
details about the development, only the direction.
Ecological indicators: These indicate the present ecosystem condition or health.
Many different indicators have been used such as specific species, specific contaminants, indices giving the composition of
groups of organisms... entropy or exergy.
Ecological goal functions: Ecosystems do not have defined goals, but their propensity to
move in a specific direction indicated by ecological orientors, can be described in ecological models by goal functions.
Clearly, in a model, the description of the development of the state variables of the model has to be rigorously indicated,
which implies that goals are made explicit. The concept should only be used in ecological modeling context.
p.115 Lotka (1925, 1956) formulated the maximum power principle. He suggested that systems
prevail that develop designs that maximize the flow of useful (for maintenance and growth) energy, and Odum
used this principle to explain much about the structure and function of ecosystems (Odum and Pinkerton, 1955).
p.143 Up to this point, the focus of this book has been on growth and development processes in ecosystems.
In fact, these are [the] most important features of ecosystem dynamics and they provide the origins of various emergent ecosystem
properties. But the picture remains incomplete if disturbance and decay are not taken into account.
p.153 Disturbances exhibit certain magnitudes (sizes, forces,
and intensities of the events, as variables of the source components), specificities (spectrum of
disturbed elements), and severities (the impacts of the events on system properties). They
can be characterized by various temporal indicators, such as their spatio-temporal scales, their duration,
abruptness, recurrence interval, frequency, or return times.
p.154 Stability has been described by several measures and concepts, such as resistance
(the system is not affected by a disturbance), resilience (the system is able to return to a referential
state), or buffer capacity, which measures the overall sensitivities of system variables related to certain
environmental input.
p.154-155 Our foregoing theoretical conceptions show both, that (a) the basic feature of natural systems
is a thermodynamic disequilibrium and that (b) ecosystems are following dynamic orientor trajectories
for most time of their existence. Steady state thus is only a short-term interval where the developmental dynamics
are artificially frozen into a small-scale average value. Therefore, more progressive indicators of ecosystem dynamics should
not be reduced to small temporal resolutions that exclude the long-term development of the system. They should much more be
oriented toward the long-term orientor dynamics of ecosystem variables and try to represent the respective potential to continue
to change instead of evaluating a system due to its potential to return to one defined (non-developmental and perhaps extremely
brittle) state.
p.155 A good potential seems to lie in the concept of resilience, if we define
it as the capacity of a disturbed system to return to its former complexifying trajectory
(not to a certain referential state). Therefore, the reference situation (or the
aspired dynamics of ecosystem management) would not be the static lines in Figure 7.5, but the orientor trajectory t.
p.160 These constraints are interacting and constantly changing; therefore, the maximum
degree of mutual adaptation is a dynamic variable as well... As ecosystems "always are recovering from the last disturbance,"
the orientor dynamics often are practically superseded by the interacting constraints dynamics.
p.166 Destructive processes are focal points of the overall ecosystem adaptability, and
they can be found on all relevant scales.
If we follow the ecosystem-based argumentation that integrity and health are relevant variables for
ecosystem evaluation, the potential for self-organizing processes becomes a key variable in environmental management.
It is strictly related to the long-term ecosystem adaptability and its buffer capacity. Therefore, human
disturbances... often reduce ecosystem adaptability, and... they set new constraints for successional pathways
p.191-192 the number of species that limits a given population (i.e. actively controls its dynamics) is
usually only one or two. Liebig's Law (Liebig, 1840), in its modern form, expresses this idea. It says that
of all the biotic or abiotic factors that control a given population, one has to be
limiting (i.e. active, controlling the dynamics) (Berryman, 1993, 2003). Time delays produced by this limiting
factor are usually one or two generations long (Berryman, 1999). Moreover, Liebig's Law stresses the importance of
limiting factors in ecology. "A factor is defined as limiting if a change in the factor produces a change in average
or equilibrium density" (Krebs, 2001).
To summarize, "the functioning of an organism is controlled or limited by that essential
environmental factor or combination of factors present in the least favorable amount. The factors
may not be continuously effective but only at some critical period"
p.199 Orientors, being holistic ecological indicators, can give further information
on the state of an ecosystem than can simply reductionistic indicators... holistic indicators allow us to
understand if the system under study is globally following a path that takes the system to a "better" or to a "worse" state...
With indicator concepts like ecosystem health, ecosystem integrity can find operational values, using information coming from
approaches like network analysis, eco-exergy [JLJ - Eco-exergy expresses the development of an ecosystem by its work capacity],
ascendency, emergy evaluation [JLJ - emergy: embodied energy - the available energy of one kind or another used up directly
and indirectly to make a service or product], and other related indicators... Regardless of the setting or objective, at its
core, holistic indicators always give a broader understanding of the amalgamation of the ecosystem parts into a context
of the whole.
p.207 The knowledge that all species in nature are complexly interconnected directly and indirectly
to all other biotic and abiotic components of their ecosystems is slow in being translated into models and
even more in management practice. [JLJ - all pieces on a game board are likewise complexly interconnected]
