Ecosystem Energy Flow and Matter Cycling Dynamics
The Energy and Matter in Ecosystems
In ecosystems, matter and energy are transferred from one entity to others through trophic relationships.
Power Flow (Energy Flow)
The energy flow is a unidirectional process. Ecosystems depend on a continuous supply of energy for their functioning. The energy enters an ecosystem primarily from the sun. Producers utilize a part of the energy reaching the Earth for photosynthesis. In this process, light energy is transformed into chemical energy, which accumulates in organic matter and is transferred to other entities through the trophic levels.
Cycle of Matter
The cycle of matter is a closed, cyclic process. Matter cycles between living things and the atmosphere, water, and Earth's crust. Matter within the ecosystem is not lost but is continuously recycled. Producers use inorganic matter and transform it into organic matter, which is then ingested by primary consumers and passes to other organisms through trophic levels.
The Trophic Parameters
These parameters allow us to better understand trophic relationships and evaluate the accumulation and transfer of matter and energy produced in an ecosystem.
Biomass
The amount of organic matter accumulated in an individual, a trophic level, or an ecosystem is expressed in grams, kilograms, or tons. Entities increase biomass through reproduction and growth.
Production
This is the amount of energy stored as biomass in each trophic level per unit of time. Trophic levels distinguish:
- Primary Production: The amount of energy captured in an ecosystem by producers through photosynthesis.
- Secondary Production: The energy captured by consumers.
Within production, differences exist:
- Gross Production: The total amount of biomass generated by any trophic level.
- Net Production: The total amount of biomass remaining available for the next trophic level.
Productivity
Productivity reflects the efficiency and status of a trophic level and relates to its production ($ ext{Productivity} = ext{Production} / ext{Biomass}$, or $P/B$). Productivity will be greater the lower the loss of biomass from one trophic level to the next.