Search results
Results from the WOW.Com Content Network
The International Union for Conservation of Nature found more than one in three tree species ... The loss of trees is a threat to thousands of plants, fungi and animals, according to the ...
The extinction of C 3 plant life is likely to be a long-term decline rather than a sharp drop. It is likely that plant groups will die one by one well before the critical carbon dioxide level is reached. The first plants to disappear will be C 3 herbaceous plants, followed by deciduous forests, evergreen broad-leaf forests, and finally ...
In 2009, UNEP mobilized action across the globe through the "Twitter for Trees" campaign. UNEP pledged to plant one tree to feed into the Billion Tree Campaign for every follower who joined from 5 May 2009 to World Environment Day on 5 June 2009. The campaign was a success, with 10,300 people following the page by World Environment Day. [16]
The island of Hispaniola was first colonized by humans 6,000 years ago and the population size was likely more than one million when the European colonists first arrived in 1492. [6] Those original inhabitants used trees and caused extinctions of birds and mammals. [11] [12] Nonetheless, the greatest deforestation occurred after 1492. [8]
[3] [4] Photoperiodic flowering plants are classified as long-day plants or short-day plants even though night is the critical factor because of the initial misunderstanding about daylight being the controlling factor. Along with long-day plants and short-day plants, there are plants that fall into a "dual-day length category".
When stocking, a tree's basal area is measured. The basal area is a cross-sectional area of the stump taken about 4.5 feet (1.4 m) above the ground. [7] The equation for calculating the basal area of trees in a stand is Basal Area = 0.005454 DBH 2, where DBH is the diameter of the tree at the aforementioned measuring height. [7]
Elephant-ear shape seedpods. Enterolobium cyclocarpum, commonly known as conacaste, guanacaste, caro caro, devil's ear tree, monkey-ear tree, or elephant-ear tree, is a species of flowering tree in the family Fabaceae, that is native to tropical regions of the Americas, from central Mexico south to northern Brazil and Venezuela. [2]
For the 300 years following the arrival of Europeans, land was cleared, mostly for agriculture, at a rate that matched that of population growth. [7] During the 19th century, while the U.S. population tripled, the total area of cropland increased by over four times, from seventy-six million to three hundred nineteen million acres.