Grasslands (also called Greenswards) are areas where the vegetation is dominated by grasses and other herbaceous (non-woody) plants. Grasslands occupy about 24% of the earth’s surface. They occur in regions too dry for forests and too moist for deserts.
The annual rainfall ranges between 25- 75 cm, usually seasonal. The principal grasslands includes Prairies (Canada, USA), Pampas (South America), Steppes (Europe and Asia), and Veldts (Africa).
The highest abundance and greatest diversity of large mammals are found in these ecosystems. The dominant animal species include wild horses, asses and antelope of Eurasia, herds of Bison of America; and the antelope and other large herbivores of Africa.
1. Producer Organisms:
In grassland, producers are mainly grasses; though, a few herbs and shrubs also contribute to primary production of biomass. Some of the most common species of grasses are: Brachiaria sp., Cynodon sp., Desmodium sp., Digitaria sp.
In grassland, consumers are of three main types:
(a) Primary Consumers:
The primary consumers are herbivores feeding directly on grasses. These are grazing animals such as Cows, Buffaloes, Sheep, Goats, Deer, and Rabbits etc. Besides them, numerous species of insects, termites, etc. are also present.
(b) Secondary Consumers:
These are carnivores that feed on primary consumers (Herbivores). These include;-Frogs, Snakes, Lizards, Birds, Foxes, Jackals etc.
(c) Tertiary Consumers:
These include hawks etc. which feed on secondary consumers.
These include wide variety of saprotrophic microorganism like: Bacteria; Fungi; Actinomycetes.
These include basic inorganic and organic compounds present in the soil and aerial environment. The essential elements like C, H, N, O, P, S etc. are supplied by water, nitrogen, nitrates, sulphates, phosphates present in soil and atmosphere.