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Ecology

Structure & Function

Diversity

Design

Environmental Impact

Structure and function are two major concepts used to describe the roles individual elements (plants, animals, water, minerals) play in creating an ecosystem. Elements will have both structural and functional components. Structure refers to the spatial relations of an ecosystem's elements. For example in a forest, trees and shrubs will form multi-layered tiers of structure, which results from light diffusion through the canopy. This type of layering is called light stratification. Wildlife will develop niches at different levels within this forest structure forming a secondary degree of structure, which is dependent on the first. Other organisms will develop niches based on the existance of the particular wildlife forming a third layer of structure dependent on the first two. Therefore, all layers (i.e. living organism) are dependent on one another for the providing the structure of the niche they inhabit. There is a direct relationship between the structural complexity that forms in an ecosystem and the diversity of species, the richness of species, the overall amount of energy held in the system, and how that energy is able to move within the system.

Function refers to the processes that move and cycle energy through and among all elements (living and non-living) within the structure of an ecosystem. Compounds, such as water, carbon, nitrogen and phosphorus, are all cycled through an ecosystem. Organisms, by the mere nature of their existance, will convert (cycle) compounds into forms that are usable by other organisms. This small conversion of energy is one link in the overall function of an ecosystem. From (re)cycling energy that is already within the system plus the daily addition of new energy (from the sun), an overall buildup of biomass begins to develop. Ecosystem function is vital to the long term growth and development of biomass.

Cycling energy within an ecosystem and building biomass is similar to creating a savings account at a bank. If a small amount of money is always put into savings, over time there will be a large amount of money in the account. If something devastating happens, there is money available that can be draw upon so that no major lifestyle changes need to be made. This is also how a healthy ecosystem functions. It is constantly receiving new energy from the sun while reusing and storing pre-formed chemical energy that is already in the system. If a disturbance occurs such as a drought, the system will have reserves (in the forms of a seed bank, wildlife, developed soils) and will be able to handle this disturbance often with little outward expression. Consider what may happen if no money is placed into savings over time and the same unforeseen catastrophe occurs; there are no reserves to draw upon. With no reserves, everyday routines and patterns must change, maybe dramatically, to adapt. If an ecosystem becomes so degraded as to loose its structure and therefore is unable to function by cycling nutrients, it too may be unable to adapt and will collapse.