Conditions that promote karst development are well-jointed, dense limestone near the surface; a moderate to heavy rainfall; and good groundwater circulation. Limestone (calcium carbonate) dissolves relatively easily in slightly acidic water, which occurs widely in nature.
Crowther said first he had to figure out how many trees are on Earth and that number was far more than anyone expected: 3.04 trillion trees, according to a study published Wednesday in the journal Nature. 14 Photos Trees Around The World.
The tallest tree in the world is named Hyperion, which reaches 379.7 feet (115.7 meters). Redwoods can achieve a diameter of 24 feet (7 meters), and 1.6 million pounds (725,700 kg). These giants can live to be 2,000 years old and have graced the planet for more than 240 million years.