CHAPTER IV 

 Ecology as a Scientific Discipline 



Ecology is the study ofwhole organisms and their relationships to each 1. Scope of Ecology 



other and to the environment. Ecology has developed out of the 



discipline of biology, and environmental biology remains as a most 



important disciplinary core. Environmental studies that do not involve 



organisms are not ecology. Yet, environmental studies within the 



biosphere, that portion of the earth where life is concentrated, are 



ecologically incomplete without including living entities and their 



effects. Ecological research has become increasingly interdisciplinary 



rather than a subdiscipline of biology. Included may be elements of 



geology, oceanography, climatology, radiology, physics, and 



biochemistry as well as aspects of health sciences, sociology, 



psychology, and other behavioral sciences that may not be thought of 



as strictly biology. 



The levels of biological organization with which ecology deals are 

 shown in Table 1 with an indication of the characteristics of each level 

 and the ecological speciality with which it is concerned. Although the 

 emphasis in modern ecology is on understanding sets of major 

 processes, or even the totality of relationships within ecosystems, 

 ecosystem research at all levels of organization is required to provide 

 information on components of the system and synthesis of these 

 components and the processes which link them. Such an 

 understanding of ecosystems provides a basis for rational 

 management of most renewable natural resources. 



Table 1: Levels of Ecological Organization 



Individual The fundamental bio- Physiological and psychological 

 logical sytem; an response to environmental 



organism change or stress. 



"Physiological ecology" 



Population The set of individuals Regulation of population 

 of the same species size and density by biotic 

 an ecosystem and abiotic factors. 



"Population ecology" 



Community A naturally occurring Interactions between 



or man-modified populations of different 



assemblage of species in a community, 



29 



567-043 O - 75 - 6 



