Is Volcanic Activity Beneficial for the Earth?

Volcanoes are powerful and land-changing elements of our planet that have the ability to build but also to destroy things. But, what are the benefits of volcanic activity for the Earth?
- Volcanoes Create Fertile Soil
Volcanic soil is very rich and productive for plants for several reasons. Volcanic lava and ash provide a variety of minerals to the soil that are important for plant growth. Volcanic soil retains water for a long time, allowing it to be used gradually by vegetation. Volcanic soil also contains high levels of phosphorous, which is important for plant growth, and crops that are grown in volcanic soils require less fertilizer and produce higher yields[sc:1].
Indonesia, the Philippines, Japan, and Italy are examples of places where people have lived in close proximity to volcanoes to take advantage of the rich soil that exists near them. Coffee and grapes are examples of two crops that grow very well in volcanic soil[sc:2].
- Volcanic Gases Add Water to the Earth
Volcanic gases add water to the Earth. In fact, 70-95% of all the gas that is emitted by a volcano during an eruption is water vapor[sc:3].
- Volcanoes Can Be a Refuge for Plants and Animals
Due to their steep inclines, volcanoes can serve as refuges for plants and animals in areas where humans have developed the land surrounding volcanoes[sc:4].
It is now thought that volcanoes may have also provided a warm refuge for plants and animals during the Earth’s past Ice Ages.
- Volcanoes Form New Land
Lava from volcanoes all around the world are constantly making islands and adding to continents. Mount Unzen in Japan, Mount St. Helens in the U.S., Etna Volcano in Italy, and Maunaloa and Kilauea in Hawaii (U.S.) are all examples of current active volcanoes around the world[sc:5].
- Volcanoes Produce Carbon Dioxide
Before humans were burning massive amounts of fossil fuels and far exceeding the Earth’s natural carbon limits, volcanoes played a critical role in contributing carbon dioxide to the atmosphere. Carbon dioxide is necessary for the photosynthetic processes of trees and other plant life.
Carbon dioxide also contributes to the greenhouse effect, which, prior to the massive human contributions of carbon dioxide into the atmosphere due to the relentless burning of fossil fuels, would help to keep our planet warm and helped to keep it from freezing. Volcanoes also provide carbon balance to the Earth, since carbon is the one of the building blocks that is important for all life on this planet.
- Volcanoes Produce Sulfur Dioxide
Volcanic sulfur contributes to global sulfur levels that help to build the proteins that are present in humans and in all other living things[sc:6].
Scientists have recently discovered that this sulfur dioxide emitted into the atmosphere by volcanoes is also helping to keep global temperatures from rising even higher than they would otherwise have risen, slowing the global warming potential of as much as 25% of global greenhouse gases from 2000-2010[sc:7].
[sc:2] http://goo.gl/X6LhoH
[sc:3] http://volcanology.geol.ucsb.edu/gas.htm
[sc:4] http://goo.gl/T5j0UT
[sc:5] http://www.geo.mtu.edu/volcanoes/world.html
[sc:6] http://www.cengage.com/biology/discipline_content/animations/sulfur_cycle.html
[sc:7] http://goo.gl/ZKMNah