Search results
Results from the WOW.Com Content Network
A pyramid of biomass shows the relationship between biomass and trophic level by quantifying the biomass present at each trophic level of an ecological community at a particular time. It is a graphical representation of biomass (total amount of living or organic matter in an ecosystem) present in unit area in different trophic levels.
The higher levels of this scheme are often referred to as an ecological organisation concept, or as the field, hierarchical ecology. Each level in the hierarchy represents an increase in organisational complexity , with each "object" being primarily composed of the previous level's basic unit. [ 2 ]
Ecological units refer to specific levels or degrees of organization within ecological systems. The units that are most commonly used and discussed within ecological systems are those at the levels of individuals, populations , communities , and ecosystems . [ 1 ]
The efficiency with which energy or biomass is transferred from one trophic level to the next is called the ecological efficiency. Consumers at each level convert on average only about 10% of the chemical energy in their food to their own organic tissue (the ten-per cent law). For this reason, food chains rarely extend for more than 5 or 6 levels.
An ecological pyramid is a graphical representation that shows, for a given ecosystem, the relationship between biomass or biological productivity and trophic levels. A biomass pyramid shows the amount of biomass at each trophic level. A productivity pyramid shows the production or turn-over in biomass at each trophic level.
An ecosystem (or ecological system) is a system formed by organisms in interaction with their environment. [2]: 458 The biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems are controlled by external and internal factors.
A country that consumes more than 1.73 gha per person has a resource demand that is not sustainable world-wide if every country were to exceed that consumption level simultaneously. Countries with a footprint below 1.73 gha per person might not be sustainable: the quality of the footprint may still lead to net long-term ecological destruction.
Trophic cascades are powerful indirect interactions that can control entire ecosystems, occurring when a trophic level in a food web is suppressed. For example, a top-down cascade will occur if predators are effective enough in predation to reduce the abundance, or alter the behavior of their prey, thereby releasing the next lower trophic level from predation (or herbivory if the intermediate ...