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Forb-Arthropod Food Chains in a One Year Experimental Field
-Used Phosphorus-32 tracers to study plant-arthropod food chains.
-Where Heterotheca subaxillaris was the labeled plant, (^32) P was transferred readily to a number of phytophagous insects and secondarily to the predator fauna.
-Where only Erigeron canadensis was tagged, there was little transfer of the isotope to the consumer populations, with the exceptions of the ant Dorymyrmex and the tree cricket Oecanthus.
- Very little 32 P was transferred to the detritus eaters during the 43 day period of the study.
“Results of this study have verified and extended the suggestion made in previous radioisotope food chain studies (Ball and Hooper 1963, Odum and Kuenzler 1963, Marples 1964) that the shape of uptake curves can be indicative of the trophic position of a population of consumers in the field. Thus, populations known to be strictly herbivorous reach a peak of radioactivity very soon after the primary producers have been labeled, while known predators such as spiders show delayed uptake at lower levels.”
Forb-Arthropod Food Chains in a One Year Experimental Field
Trophic Structure and Productivity of a Windward Coral Reef
Community on Eniwetok Atoll
- Linked application of ecosystems ecology with nuclear technologies
- Mutualism and stability
- System characterized not by competition and growth, but by cooperation and stability
The ecosystem is the basic unit of nature with which ecologists
must ultimately deal
- President of ESA in 1964
- Announced in Bioscience the establishment of a “new ecology” that had risen “to a front line position in man’s thinking as a consequence of the exploitation of atomic energy, the exploration of outer space, and the human population explosion.”
- Defined the new ecology as a “ Systems Ecology” that deals with “the structure and function of levels of organization beyond that of the individual and species”
The Strategy of Ecosystem Development
-“In the pioneer society, as in the pioneer ecosystem, high birth rates, rapid growth, high economic profits, and exploitation of accessible and unused resources are advantageous, but, as the saturation level is approached, these drives must be shifted to considerations of symbiosis(that is, civil rights, law and order, education, and culture), birth control, and the recycling of resources.”
-The use of nonchemical pest control agriculture
- The implementation of a compartment model for landscape zoning to be supported by landscape lawyers
- A reorientation of societies goals to be accomplished by instruction in ecosystems ecology beginning in elementary school.
Criticism of The Strategy of Ecosystem Development
-1973, William Drury and Ian Nesbit published an article called succession that challenged Odums ecosystem concept
-Promoted Glesonian concept of succession
The Pulsing Paradigm
-Abandoned the term homeostasis
- Began using the term homeorhesis
- derived from the Greek word rheos for “stream” or “current” and means maintenance of flow
Non-Set-Point Control
Set-Point Control
Set-Point Control
Thyroid Gland
Information (^) Hormones
Metabolism
