[dgt20 (OP)]

How does grassland ecosystem differ around the world? So far I've looked at different animals, e.g: in African grasslands, its full of lions, elephant, rhino's, etc whereas Australian grasslands consist of kangaroo's, wallabies, etc.

Does vegetation of grasslands differ around the world as well such as species of grasses? If so what kinds?

Another factor I looked at was how different countries grassland consist of different climate is this true?

[alancalverd]

Intriguing subject, and all the more so for being both obvious and unanswered!

The Australian land fauna are not only unique (marsupial) but remarkably free of large carnivores. One might guess that the  kangaroos evolved such strength, agility, and adaptation to  desert conditions, that they outperformed their predators. But the predator population of other lands is very small compared with the prey, so the absence of even one family of native cats is strange.

Don't forget the North American grassland. It's easy to ignore because Western eyes don't consider bison and wolves to be particularly exotic, but it's completely different again from African and Australian fauna!

[evan_au]

Australian grasslands consist of kangaroo's, wallabies, etc.

You are only looking at Australia after the arrival of humans.

Prior to the arrival of humans, the Australian landscape was quite different, with megafauna like rhino-sized diprotodons as vegetation grazers, 3 meter-tall kangaroos, a marsupial lion, 5 meter-long carnivorous lizards and large snakes. Much of Australia that is now desert was covered by vegetation.

Once humans arrived, the larger animals died off (eaten by humans, loss of habitat or affected by climate change) and the vegetation died off (burnt by humans or affected by climate change or affected by changes in fauna).
See: https://en.wikipedia.org/wiki/Australian_megafauna

A similar pattern has occurred everywhere humans visited. It is a choice of "domesticate or perish".
See: https://en.wikipedia.org/wiki/Megafauna#Megafaunal_mass_extinctions

Only in Africa have wild megafauna persisted despite the presence of humans. Some have suggested that this is because the African megafauna co-evolved with humans. On all other continents, humans were a novel invasive species that wiped out the native megafauna, with corresponding impacts on vegetation. 

I heard that one of the drivers for de-extincting the mammoth is to restore the Siberian tundra to grasslands and save on CO₂ emissions.

Towards the end of this podcast, Stewart Brand talks about the project to resurrect the mammoth.
See: https://after-on.com/episodes/030