Aquatic ecology and Biodiversity

Unit 2- Ecosystem ecology

2.2.1. Energy flow
Energy is the ability to do work. Main source of the energy in aquatic ecosystem is the radiant energy or light energy derived from the sun

Ecosystems are composed of a variety of abiotic components such as soil, water, atmosphere, radiation from the sun. Soils provide nutrients, water act as home and a medium for organisms. The atmosphere provides carbon dioxide for photosynthesis and oxygen for respiration. Sunlight is necessary for photosynthesis. Photosynthesis provides the energy for plant growth and metabolism and the organic food for animal life. Plants and animals receive their water from the earth's surface and soil.

Ecosystems are also composed of living organisms such as producers, consumers and decomposers. Producers or autotrophs can manufacture their food through the process of photosynthesis. Consumers get their energy and nutrients by feeding directly or indirectly on producers. Herbivores are consumers that eat plants for their energy and nutrients. Consumer organisms that feed on this organic matter or detritus are known as detritivores or decomposers. The organic matter that is consumed by the detritivores is eventually converted back into inorganic nutrients in the soil. Energy flow and energy transformation in an ecosystem obeys the law of thermodynamics