Question

How is terrestrial/freshwater/marine biodiversity distributed across the globe?

Answer 1

Terrestrial biodiversity includes many taxa of plants, animals and microorganisms on the land of earth. It also includes land habitats such as forests, grasslands, desert and wetland ecosystems. Each plant and animal a species, has a unique contribution to our world. Forests help to nurture all life around 300 million people on the planet by providing people with food, medicine, fresh water and clean air, and livelihoods.

Freshwater biodiversity covers 1% of world's surface. It includes the biodiversity rich in rivers (flows water), lakes (large areas of stamding water) and wetlands (land covered with water, trees and plants) exists across the globe. Freshwater biodiversity provides food, fibre, drinking water and recreational activity, the thread of life. Fresh water biodiversity is a part of landscape, provide water to support plants. At species level, freshwater biodiversity includes fish, amphibians (eg. frog), mammals (eg. dolphins), water birds (eg. cranes), reptiles (eg. crocodiles), insects (eg. mosquitos), vascular plants (eg. water lilly), microalgae (eg. diatom), and aquatic plants (eg. rice). Species extinction in freshwater biodiversity is faster than terrestrial and marine biodiversity due to habitat loss via overharvesting and pollution.

Marine biodiversity covers three-fouths of the earth's surface. Marine bodiversity includes oceans, seas, coral reefs, and estuaries. Estuaries are wetlands near the surface of oceans that flows into the ocean and the border of these two is called ectotone. Ectotome having higher biodiversity because of the blending of species from estuary and ocean system. Wetlands having a mix of fresh water and salt water with salinity ranges from 0.5 ppt to 17ppt. Coral reefs are widely distributed in shallow oceans. Corals are the dominant organism in coral reefs. At species level, marine biodiversity includes 845 species of coral reefs (eg. a symbiont between blue algae and animal polyp), 1046 species of shark (eg. mako shark), 349 species of seabirds (eg. gull), 134 species of marine mammals (eg. dolphins), 7 species of marine turtles (eg. green sea turtle), sea grasses ans mangroves.