Ecosystem — Part 1: Structure, productivity and decomposition: visual lesson, ISC Class 12 Biology

Lesson

The ecosystem

Part 1 — what an ecosystem is, how much it produces, and how dead matter is recycled.

In this lesson you will

Define an ecosystem, name its types, and describe the structure and function of a pond
Distinguish GPP, NPP and secondary productivity; explain PAR, standing crop and standing state
Describe the steps of decomposition and the factors that affect its rate

Concept

Ecosystems vary in size from a small pond to a large forest or sea.

Table of types and components of ecosystems
Category	Examples or members
Terrestrial	Forest, grassland, desert
Aquatic	Pond, lake, wetland, river, estuary
Man-made	Crop fields, aquarium
Biotic components	Producers, consumers, decomposers
Abiotic components	Water, soil, minerals, light, temperature

Diagram

A pond is a shallow water body showing all the basic components of an ecosystem.