Presentation on theme: "Howard Thomas (H.T.) Odum Community Ecology from the System’s Perspective Ben Branoff BIO 7083 4/31/2012."— Presentation transcript:
Howard Thomas (H.T.) Odum Community Ecology from the System’s Perspective Ben Branoff BIO /31/2012
Biography – Born, 1924: Chapel Hill, N.C. – Father: Howard W. Odum, sociologist father "encouraged his sons to go into science and to develop new techniques to contribute to social progress ”. – Brother: Eugene Odum, ecologist – Founded the Wetlands Center at the University of Florida – 1973 First of its kind to focus on wetlands – Howard Odum, either alone or with his brother Eugene, received essentially all of the international prizes awarded to ecologists. – Died, 2002: Gainesville, FL
Academia B.Sc. Zoology, UNC Chapel Hill Main interest was ornithology Ph.D. Zoology, Yale University G.E. Hutchinson Began to take an interest in System’s Ecology – The Biogeochemistry of Strontium: With Discussion on the Ecological Integration of Elements Began collaboration with brother – Co-wrote “Fundamentals of Ecology” in 1953 Introduced the language of “energese” describing the flow of energy in an ecosystem – Professor, University of Texas 1963 – Professor, UNC Chapel Hill 1970 – Professor, University of Florida Founded the Center for Wetlands, UF Founded and directed the Center for Environmental Policy, UF 1996 – Retired 49 years in academia
Impact CitationsAuthorTitleDateJournal 1613HT Odum Environmental accounting: emergy and environmental decision making1996book 1501HT OdumEnvironment, power and society.1971book 1061HT OdumSystems Ecology; an introduction1983book 862HT OdumPrimary production in flowing waters1956Limnology and oceanography 702HT Odum Self-organization, transformity, and information1988Science 664HT Odum Trophic structure and productivity of Silver Springs, Florida1957Ecological monographs 655HT Odum… Trophic structure and productivity of a windward coral reef community on Eniwetok Atoll1955Ecological Monographs 463HT Odum…Energy basis for man and nature HT Odum… Time's speed regulator: the optimum efficiency for maximum power output in physical and biological systems1955American Scientist 294HT Odum Ecological and general systems: an introduction to systems ecology1994 Search: “HT Odum” Papers:681 Citations:17,374 H-index:57 Years:66 Cites/year:263 Cites/paper:25 papers/year:10
Impact One of the first to publish in the following areas: Ecological modeling (Odum 1960) Ecological engineering (Odum et al. 1963) Ecological economics (Odum 1971) Estuarine ecology (Odum and Hoskins 1958) Tropical ecosystems ecology (Odum and Pidgeon 1970) General systems theory. Pioneered the use of microcosms Influenced the construction of Biosphere 2 Influential in space systems life support Introduced Ecological Engineering Ecosystem modeling Ecosystem design Energetics Rigorously applied energy concepts to ecosystems Introduced “Energese”, the energy system’s language
Systems Ecology “…seeks a holistic view of the interactions and transactions within and between biological and ecological systems.” - R.L Kitching Odum believed energy was the primary controlling mechanism of an ecosystem, determining predictive ecological characteristics such as community assemblages, productivity and function.
Energese A language of ecological energy Founded on the principles of electrical circuits. Used modules or classes of symbols to represent unique ecological components
Energese A simple, generalized language provides a common reference for ecological comparisons
Energese Simple or complex…. Provide a conceptual framework for ecosystem function. Qualitative Inferences can be made on these alone. Quantitative analyses can be done by assigning real numbers for diagram components.
Energese Generalized River System
Energese Pesticide effects on aquatic ecosystems
Why Energy? Energy is the fundamental unit of work in the universe. Nothing can be done or undone without energy. Therefore, any observations, at any level, can be traced back to fundamental laws of energy. Psychology Human behavior Biology Chemistry Physics Energy Ecological Function Biology Chemistry Physics Energy
“One of the most natural ways to describe a community or an ecosystem is in terms of the trophic relationships among species, and the tangled web that results. (…;Odum, 1983;…) Why Energy? Levin, The Problem of Pattern and Scale in Ecology: Robert H. MacArthur Award Lecture
Why Energy? Reiss, Brown and Lane, Characteristic community structure of Florida’s subtropical wetlands… …developed a Florida wetland condition index (FWCI) composed of indicators of community structure in the diatom, macrophyte, and macroinvertebrate assemblages… The landscape development intensity index (LDI) was used to quantify the human disturbance gradient
The underlying concept behind calculating the LDI index, which quantiﬁes the nonrenewable energy use per unit area in the surrounding landscape, stems from earlier works by Odum (1996).” Changes in community structure can be detected along a gradient of human land use activities adjacent to wetland ecosystems. Results suggested that the LDI index was able to couple the disparate effects of human landscape modiﬁcation, such as altered hydrology… or trampling/selective herbivory …, into a single value, which was assumed to be manifested by changes in community composition. Why Energy? Reiss, Brown and Lane, Characteristic community structure of Florida’s subtropical wetlands…
Lotka-Volterra predator prey Donalson and Nisbet (1999) found interesting time series when the Lotka/Volterra prey/predator model was simulated with stochastic births and deaths and a spatial dimension. Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Lotka-Volterra predator prey “However, models with mean intrinsic rate of reproduction constant are models with unlimited energy not valid in nature. Adding stochastic variation as if there is inherent randomness is not realistic either, if variation in the real world comes from energy constrained oscillations of the smaller scale.” Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Species diversity with latitude “Some empirical equations for the change in species number with latitude and with area were combined by Lyons and Willig (2000) and compared with biogeographic data on ranges of marsupials and bats.” Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Species diversity with latitude less energy is available for the mechanisms of species interaction and niche separation necessary to prevent competitive elimination. The energy systems theory finds the increase of energy needed to support species rising in proportion to the inter-species interactions (Odum and Pigeon, 1970; Odum, 1971). Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Deer mice selective feeding Morris and Davidson (2000) tested three aspects of deer mice behavior to see if their feeding choices were beneficial to reproductive success The mice chose areas with more forest cover from carnivores and minimized their time and feeding effort in less secure areas. Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Deer mice selective feeding An energy systems view expects appropriate populations of plant food, prey, and predator populations that keep the whole system at maximum performance. Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Galapagos Finches and El Niño Grant et al. (2000) showed Galapagos finches adapting their breeding efforts, populations, and control of arthropods, increasing in years when higher sea temperature produces higher atmospheric vapor pressures, cloud cover shading, lower temperatures, and rain. Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Galapagos Finches and El Niño With the pulsing that favors maximum power provided by El Nino, the finch populations contribute to ecosystem performance by adjusting their load and their services to the cycle without developing a destructive prey/predator cycle. Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Conclusions Odum saw energy as the primary control of ecological function. – All processes can be thought of as their role in the energy budget of a system. "A whole generation of citizens thought that the carrying capacity of the earth was proportional to the amount of land under cultivation and that higher efficiencies in using the energy of the sun had arrived. This is a sad hoax, for industrial man no longer eats potatoes made from solar energy, now he eats potatoes partly made of oil.“ – H.T. Odum He presented novel ideas to the study of ecology. – Many of these are controversial "I have played many roles sometimes with the majority, but more often attempting to shock the scientific establishment into a better view.“ – H.T. Odum – Many of them have been used with great success in applied ecology. "Nature has all the answers, so what is your question?“ – H.T. Odum
“…Odum advanced several suggestive hypotheses about biological communities and the partitioning of energy; for example, that the ratio of total community production to total community respiration determined the character of the biological community.” Why Energy? Taylor, Technocratic Optimism, H.T. Odum and the Partial Transformation of Ecological Metaphor after World War II.
“One might think that ecologists study ecosystems, but most scientists who call themselves ecologists are students of genetics, organisms, populations and communities.” “For instance, fisheries ecologists have focused their research for years on predator-prey interactions and only recently have they attempted to integrate parameters such as nutrients, water temperature and regional oceanography into their biologic models. It is a rare ecologist who studies the function and structure of whole ecosystems.” However, our research and that of others suggest that the search for simple causal rules of ecosystem behaviour is futile. The diversity-stability hypothesis of ecology is a classic example of the kind of simple rule that environmental managers seek. The diversity-stability hypothesis arose from a paper of MacArthur in which he proposed that the diversity of a food web was a measure of community stability. Goodman” wrote a paper which systematicatty examined the literature and demonstrated clearly that there was no scientific basis for the diversity-stability hypothesis. However, it is still widely believed that preserving species diversity is crucial to maintaining the health of ecosystems.3 Why Energy? Schneider and Kay, Complexity and Thermodynamics, Towards a New Ecology
“There is in ecological growth a paradox of constraint in which components diversify but behavior narrows under diminishing resource availability with maturation.” Why Energy? Patten, Straškraba and Jørgensen, Ecosystems Emerging. 5: Constraints. Diversity Resources Behavior Resources
“There is in ecological growth a paradox of constraint in which components diversify but behavior narrows under diminishing resource availability with maturation.” “Eutrophic, resource-rich systems of early succession are nutritionally less constrained and display correspondingly less competition. In these, biodiversity is low (the paradox).” Why Energy? Patten, Straškraba and Jørgensen, Ecosystems Emerging. 5: Constraints.
“There is in ecological growth a paradox of constraint in which components diversify but behavior narrows under diminishing resource availability with maturation.” “Oligotrophic, resource-poor systems are nutrient impoverished due to primary scarcity, fuller utilization, sequestration, and other limiting processes. Constraint and competition are high, and increased biodiversity reflects increasing need to specialize. Examples include tropical forests and coral reefs. Classic r- and K-selection of population and community ecology capture these observations...” Why Energy? Patten, Straškraba and Jørgensen, Ecosystems Emerging. 5: Constraints.
Bird fleas Tripet and Richner (1999) found intra-specific competition regulating the concentrations of bird fleas developing on host birds (blue tits). Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.
Bird fleas A stable parasite population did not overload the birds physiology and helped sustain the host population’s role in the ecosystem. However, larval ﬂeas can be considered virulent, in the sense that increases in their population density, growth rate, or efﬁciency may reduce ﬁtness components of hosts, because larvae require resources that only adults can provide via feeding on host blood Why Energy? Odum, Explanations of ecological relationships with energy systems concepts.