The Trophic-Dynamic Aspect of Ecology Raymond L. Lindeman
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The Trophic-Dynamic Aspect of Ecology Raymond L. Lindeman Ecology, Vol. 23, No. 4. (Oct., 1942), pp. 399-417. Stable URL: http://links.jstor.org/sici?sici=0012-9658%28194210%2923%3A4%3C399%3ATTAOE%3E2.0.CO%3B2-P Ecology is currently published by Ecological Society of America. Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/about/terms.html. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at http://www.jstor.org/journals/esa.html. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. The JSTOR Archive is a trusted digital repository providing for long-term preservation and access to leading academic journals and scholarly literature from around the world. The Archive is supported by libraries, scholarly societies, publishers, and foundations. It is an initiative of JSTOR, a not-for-profit organization with a mission to help the scholarly community take advantage of advances in technology. For more information regarding JSTOR, please contact [email protected]. http://www.jstor.org Mon Sep 24 13:51:25 2007 THE TROPHIC-DYNAMIC ASPECT OF ECOLOGY RAYMONDL. LINDEMAN Osborn Zoological Laboratory, Yale University Recent progress in the study of aquatic community. A more "bio-ecological" food-cycle relationships invites a re- species-distributional approach would appraisal of certain ecological tenets. recognize both the plants and animals Quantitative productivity data provide as co-constituents of restricted "biotic" a basis for enunciating certain trophic communities, such as "plankton com- principles, which, when applied to a munities," "benthic communities," etc., series of successional stages, shed new in which members of the living commu- light on the dynamics of ecological nity "co-act" with each other and "re- succession. act" with the non-living environment (Clements and Shelford, '39 ;Carpenter, '39, '40; T. Park, '41). Coactions and reactions are considered bv bio-ecoloaists A chronoloaical- review of the maior u viewpoints guiding synecological thought to be the dynamic effectors of succession. indicates the following stages: (1) the The trophic-dynamic viewpoint, as static species-distributional viewpoint; adopted in this paper, emphasizes the (2) the dynamic species-distributional relationship of trophic or "energy-avail- viewpoint, with emphasis on successional ing" relationships within the community- phenomena; and (3) the trophic-dynamic unit to the process of succession. From viewpoint. From either species-distri- this viewpoint, which is closely allied to butional viewpoint, a lake, for example, Vernadsky's "biogeochemical" approach might be considered by a botanist as (cf. Hutchinson and Wollack, '40) and containing several distinct plant aggre- to the "oekologische Sicht" of Friederichs gations, such as marginal emergent, ('30), a lake is considered as a primary floating-leafed, submerged, benthic, or ecological unit in its own right, since all phytoplankton communities, some of the lesser "communities" mentioned which might even be considered as above are de~endentuDon other com- "climax" (cf. Tutin, '41). The associ- ponents of the lacustrine food cycle (cf. ated animals would be "biotic factors" figure 1) for their very existence. Upon of the plant environment, tending to further consideration of the trophic cycle, limit or modify the development of the the discrimination between living organ- aquatic plant communities. To a strict isms as parts of the "biotic community" zoologist, on the other hand, a lake would and dead organisms and inorganic nutri- seem to contain animal communities tives as parts of the "environment" roughly coincident with the plant com- seems arbitrary and unnatural. The munities, although the "associated vege- difficulty of drawing clear-cut lines be- tation" would be considered merely as a tween the living communityand the non- part of the environment l of the animal living environment is illustrated by the difficulty of determining the status of a t The term habitat is used by certain ecologists slowly dying pondweed covered with (Clements and Shelford, '39; Haskell, '40; T. Park, '41) as a synonym for environment in the periphytes, some of which are also con- usual sense and as here used, although Park tinually dying. As indicated in figure 1, points out that most biologists understand "hab- much of the non-living nascent ooze is itat" to mean "simply the place or niche that rapidly reincorporated through "dis- an animal or plant occupies in nature" in a species-distributional sense. On the other hand, be hoped that ecologists will shortly be able to Haskell, and apparently also Park, use "environ- reach some sort of agreement on the meanings ment" as synonymous with the cosmos. It is to of these basic terms. i99 400 RAYMOND L. LINDEMAN Ecology, Vol. 23, No. 4 solved nutrients" back into the living magnitude, i.e., the biotic community "biotic community." This constant or- plus its abiotic environment. The con- ganic-inorganic cycle of nutritive sub- cept of the ecosystem is believed by the stance is so completely integrated that writer to be of fundamental importance to consider even such a unit as a lake in interpreting the data of dynamic primarily as a biotic community appears ecology. to force a LLbiological"emphasis upon a more basic functional organization. This concept was perhaps first ex- pressed by Thienemann ('18), as a result Qua1itati.de food-cycle relationships of his extensive limnological studies on the lakes of Korth Germany. Allee ('34) Although certain aspects of food rela- expressed a similar view, stating: "The tions have been known for centuries, picture than finally emerges . is of a many processes within ecosystems are sort of superorganismic unity not alone still very incompletely understood. The between the plants and animals to form basic process in trophic dynamics is the biotic communities, but also between the transfer of energy from one part of biota and the environment." Such a the ecosystem to another. All function, concept is inherent in the term ecosystem, and indeed all life, within an ecosystem proposed by Tansley ('35)for the funda- depends upon the utilization of an exter- mental ecological unit.2 Rejecting the nal source of energy, solar radiation. terms "complex organism" and "biotic portion of this incident energy is trans- community," Tansley writes, "But the formed by the process of photosynthesis more fundamental conception is, as it into the structure of living organisms. seems to me, the whole system (in the In the language of community economics sense of physics), including not only the introduced by Thienemann ('26), auto- organism-complex, but also the whole trophic plants are producer organisms, complex of physical factors forming what employing the energy obtained by photo- we call the environment of the biome. synthesis to synthesize complex organic . It is the systems so formed which, substances from simple inorganic sub- from the point of view of the ecologist, stances. Although plants again release are the basic units of nature on the face a portion of this potential energy in cata- of the earth. These ecosystems, as bolic processes, a great surplus of organic we may call them, are of the most vari- substance is accumulated. Animals and ous liinds and sizes. They form one heterotrophic plants, as consumer organ- category of the multitudinous physical isms, feed upon this surplus of potential systems of the universe, which range energy, oxidizing a considerable portion from the universe as a whole down to of the consumed substance to release the atom." Tansley goes on to discuss kinetic energy for metabolism, but trans- the ecosystem as a category of rank forming the remainder into the complex equal to the "biome" (Clements, '16), chemical substances of their own bodies. but points out that the term can also Following death, every organism is a be used in a general sense, as is the word potential source of energy for saproph- "community." The ecosystem may be agous organisms (feeding directly on formally defined as the system composed dead tissues), which again may act as of physical-chemical-biological processes energy sources for successive categories active within a space-time unit of any of consumers. Heterotrophic bacteria and fungi, representing the most im- The ecological system composed of the "bio- portant saprophagous consumption of coenosis + biotop " has been termed the holocoen by Friederichs ('30)and the biosystem by Thiene- energy, may be conveniently differenti- mann ('39). ated from animal consumers as special- October, 1942 TROPHIC-DYNAMIC ASPECT OF ECOLOGY 401 Sdar Radiation Solor Radiation FIG.1. Generalized lacustrine food-cycle relationships (after Lindeman, '4lb). ized decomposers3 of organic substance. solved nutrients once more in resynthe- Waksman ('41) has suggested that cer- sizing complex organic substance, thus tain of these bacteria be further differ- completing the food cycle. entiated as transformers of organic and The careful study of food cycles re- inorganic compounds. The combined