A socio-ecological system consists of 'a bio-geo-physical' unit and its associated social actors and institutions.
Contribution Margin. Contribution margin is a productâs price minus all associated variable costs, resulting in the incremental profit earned for each unit sold. The total contribution margin generated by an entity represents the total earnings available to pay for fixed expenses and to generate a profit. The contribution margin concept is useful for deciding whether to allow a lower price in special pricing situations.
Theoretical basis [edit]. Contribution margin per unit is the difference between the price of a product and the sum of the variable costs of one unit of that product.heoretical basis [edit]. Contribution margin per unit is the difference between the price of a product and the sum of the variable costs of one unit of that product.