Odum offers the vision and the means to consider ecology at any scale --to look at the grand ('systems ecology') as well as the minuscule, and to appreciate the essentially dynamic nature (his current term is 'pulsing') of ecological systems.
So what should we DO to comprehend Odum? What could we attempt? Following are some paths I've explored, and it's worth thinking about what search strategies make sense. This is a case in point for the utility of the approaches and tools we've been looking at.
"Howard T. Odum": AltaVista 83
Emergy "is the available energy of one kind previously used up directly and indirectly to make a service or product" (Odum 1996:7)
Some representative links:
Energy, Entropy, Economics and Ecology (http://www.aloha.net/~jhanson/page17.htm)
"Solar emergy is the solar energy availability used up directly and indirectly to make a service or product. Its unit is the solar emjoule.
"Solar transformity is the solar emergy required to make one joule of a service or product. Its unit is solar emjoules per joule. " [p.p. 201-203]
(see also http://www.aloha.net/~jhanson/page1.htm)
Complex Ecology: Network Properties In Ecosystems (http://www.pz-oekosys.uni-kiel.de/~maren-l/abstract/abs_a12.htm) [Patten & Fath --happens to mention a 1981 article with an interesting title and this trenchant passage:]
Many ecologists prefer not to think about ecosystems at all. For them, the theory of ecology is complete with the organism and its evolving population. Organisms feed upon and compete with one another in an environment which is unnecessary to define beyond 'carrying capacity.' Out of such direct interactions with immediate neighbors derives the natural selection of chance genetic variations that constitutes evolution. The successful organism, best adapted over all alternatives to that which remains unspecified, maximizes the frequency of its genotype within the populations of its species. The theory is pat, and environment is always there, prepared and ready to accomodate another cycle of the process. For us, we must ask how it is that environment is always prepared and ready; why did it not become chaotic long ago, a disorganized heap of unprocessed and partially processed energy-matter residues from the evolutionary biology of past ages? The theory of ecology is not pat for us. We believe that to understand the organism in nature, its other half, environment, will have to be understood as well. To us, "environment" means environment unspecified, but "ecosystem" is environment specified. The ecosystem is the level of organization concerned with the orderly, not chaotic, processing of energy-matter in the biosphere. We do not believe that it is the goal of ecosystems to do this. They are not superorganisms. Rather, it is a constraint of existence that if living processes are not orderly, antientropic, then they will not persist. The balance of nature calls for a conjugate action-reaction kind of organization that creates order where there could be chaos as a matter of implicit design that simply evolved over geologic time.
Patten, Bernard C. and Howard T. Odum
The cybernetic nature of ecosystems.
American Naturalist (1981) 118:886-895
My own interest in Odum grew out of reading I had done in general system theory and my struggles to comprehend agricultural production systems and their trajectories. Here are two items which summarize nicely:
Agricultural ecosystems (referred to as agroecosystems) have been described by Odum (1984) as domesticated ecosystems. He states that they are in many ways intermediate between natural ecosystems (such as grasslands and forests) and fabricated ecosystems (cities).
Agroecosystems are solar powered (as are natural systems) but differ from natural systems in that:
- there are auxiliary energy sources that are used to enhance productivity; these sources are processed fuels along with animal and human labor;
- species diversity is reduced by human management in order to maximize yield of specific foodstuffs (plant or animal);
- dominant plant and animal species are under artificial rather than natural selection; and,
- control is external and goal-oriented rather than internal via subsystem feedback as in natural ecosystems.
Agroecosystems do not happen without human intervention in the landscape. Therefore, creation of these ecosystems (and maintenance of them as well) is necessarily concerned with the (human) economic goals of production, productivity, and conservation. Agroecosystems are controlled, by definition, by management of ecological processes.(http://www.nhq.nrcs.usda.gov/BCS/agecol/agecodef.html)
'Potatoes Made of Oil': Eugene and Howard Odum and the Origins and Limits of American AgroecologyMark Glen Madison
Environment and History 3(1997): 209-238
Eugene P. Odum (b. 1913) and Howard T. Odum (b.1924) were at the forefront of the 'new ecology' of ecosystems, in the 1950s and 1960s. As part of their programme the Odums were firmly committed to bringing both natural and human ecosystems into accord with the laws of ecoenergetics (the flow of energy through a system). American agriculture struck the Odums as a particularly egregious violator of all the laws of ecoenergetics and hence a dangerous paradigm for world development. By diagramming American agriculture as a simplified circuit of energy inputs and outputs, the Odums concluded that energy subsidies had created a dangerously unstable system. As a remedy they suggested an end to the Green Revolution and a modification of human society so as to better approach the steady-state of a mature natural ecosystem. To achieve their programme goals the Odums needed to enlist the support of their fellow ecologists and the government. In this attempt the Odums were largely unsuccessful, as the ecological community and the US government largely ignored their attempt to reform agriculture. While the Odums' agroecological language and theories have persisted until the present, they have largely been divested of the brothers' broader programme of bringing the entire human ecosystem into accord with natural laws. By re-examining the social and scientific context of the Odums' early agroecology it may be possible to better evaluate agroecology as both a tool and a social programme.
Nature's pulsing paradigm
Odum, WE; Odum, EP*; Odum, HT
AF: Author Affiliation
Inst. Ecol., Univ. Georgia, Athens, GA 30601, USA
Pulsed Ecosystems: A New Paradigm?, Hilton Head, SC (USA), Nov 1993
Blum, LK (ed)
PULSED ECOSYSTEMS: A NEW PARADIGM? PROCEEDINGS OF A SYMPOSIUM HELD IN HILTON HEAD, NOVEMBER 1993., 1995, pp. 547-555, ESTUARIES, vol. 18, no. 4
While the steady state is often seen as the final result of development in nature, a more realistic concept may be that nature pulses regularly to make a pulsing steady state-a new paradigm gaining acceptance in ecology and many other fields. In this paper we compare tidal salt marshes, tidal freshwater marshes, and seasonally flooded freshwater wetlands as examples of pulsed ecosystems. Despite marked differences in species composition, biodiversity, and community structure, these wetland types are functionally similar because of the common denominator of water flow pulses. Often a period of high production alternates with a period of rapid consumption in these fluctuating water-level systems, a biotic pulsing to which many life histories, such as that of the wood stork, are adapted. Pulsing of medium frequency and amplitude often provides an energy subsidy for the community thus enhancing its productivity. The energy of large-scale pulses such as storms are usually dissipated in natural ecosystems with little harm to the biotic network; however, when seawalls, dikes, or stabilized sand dunes are constructed to confront these strong pulses, the whole ecosystem (and associated human structures) may be severely damaged when the barriers fail because too much of the storm energy is concentrated on them. The relationship between biologically mediated internal pulsing, such as plant-herbivore or predator-prey cycles, and physical external pulsing is discussed not only in wetlands but in other ecosystem types as well. An intriguing hypothesis is that ecosystem performance and species survival are enhanced when external and internal pulses are coupled. We suggest that if pulsing is general, then what is sustainable in ecosystems, is a repeating oscillation that is often poised on the edge of chaos.
SL: Summary Language
PY: Publication Year
PT: Publication Type
Book Monograph; Conference
salt marshes; marshes; wetlands; brackishwater ecology; ecosystems; tidal effects; estuarine dynamics; biological production; physicochemical properties; environmental factors; ecosystem dynamics
ER: Environmental Regime
Marine; Brackish; Freshwater
TR: ASFA Input Center Number
Q1 01482 Ecosystems and energetics; O 1070 Ecology/Community Studies; D 04300 Aquatic ecosystems - general
ASFA 1: Biological Sciences & Living Resources; Oceanic Abstracts; Ecology Abstracts
And here's an example of the scale of Odum's vision: an energetic model of Italy:
Emergy use, environmental loading and sustainability. An emergy analysis of Italy
Ulgiati, S; Odum, HT; Bastianoni, S
AF: Author Affiliation
Dep. Chem., Univ. Siena, Pian dei Mantellini 44, 53200 Siena, Italy
ECOL. MODEL., vol. 73, no. 3-4, pp. 215-268, 1994
Maximizing emergy flow is the new statement (Odum, 1988a, 1991) of Lotks'a maximum power principle (1922a,b): self-organizing systems which maximize emergy flow and reinforce production are sustainable, the others are displaced by those with better reinforcement of their productive basis. An emergy analysis of the Italian system of economy and nature was performed in order to study its sustainability and emergy use. Indices of thermodynamic and economic vitality of Italy were evaluated and a comparison with indices of other developed and developing countries was performed.
SL: Summary Language
PY: Publication Year
PT: Publication Type
ecosystem analysis; production; economics; resource utilization; costs; Italy; sustainable development; ecosystems
D 04003 Modeling, mathematics, computer applications; D 04890 Planning/development; P 9000 ENVIRONMENTAL ACTION
Ecology Abstracts; Pollution Abstracts