What is Forest : A forest is a highly complex, constantly changing Environment made up of a variety of living things (wildlife, trees, shrubs, wildflowers, ferns, mosses, lichens, fungi and microscopic soil organisms) and non-living things (Water, Nutrients, Rocks, Sunlight & Air). Trees are the biggest part of this complex community
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There are many different kinds of forests around the world—tropical rain forests, temperate rain forests, boreal forests, mangrove forests, Carolinian forests... to name but a few. In Canada, we have eight different forest regions; the Boreal, Subalpine, Montane, Coast, Columbia, Deciduous (Carolinian), Great Lakes/St. Lawrence and Acadian forest regions.
What is Afforestation: Afforestation is the planting of trees to create a forest on non-forest land. It is different from reforestation, which is replanting trees where a forest has been depleted. The main purposes for implementing afforestation are commercial forestry and environmental restoration or preservation.
When afforestation is used for commercial purposes, it usually involves planting and harvesting of trees as agricultural crops. Areas where this is done are known as plantation forests. Harvesting trees from plantation forests helps to reduce deforestation in natural forests. On the other hand, there may be environmental consequences if this tree-farming is done incorrectly. The fast-growing trees often chosen for plantation forests consume large amounts of water and may deplete the area's water resources. Some types of trees also change the physical or chemical properties of the soil, which can damage indigenous species. Thus, sustainable commercial afforestation must take environmental factors into account to avoid damaging the local ecosystem.

What is Deforestation: Deforestation refers to the cutting, clearing, and removal of rainforest or related ecosystems into less bio-diverse ecosystems such as pasture, cropland, or plantations.
What are the causes of deforestation?
I. Logging
II. Mining
III. Oil and gas extraction
IV. Cattle ranching
V. Agriculture: Cash crops.
VI. Local, National, and International factors: development, land titles, government subsidies to attract corporations into developing countries, trade agreements (NAFTA, CAFTA), civil wars, debt, lack of resources, and lack of law enforcement.

What is Reforestation: As trees are cut down for lumber and to clear land for farming and development, the impact on the Earth multiplies. Without the biomass in forests to sequester carbon and produce oxygen, the air quality becomes worse and planet temperatures may be affected. Soil erosion occurs, damaging water systems, and it negatively impacts farming. The natural habitats of a wide range of animals is damaged or completely destroyed. Also, as the trees are cut, this natural resource becomes more and more limited.
To combat these problems, reforestation plans have been implemented worldwide. Reforestation is the systematic replanting of trees, attempting to replace what has been lost. Some plans try to replace cut trees, while others try to develop stronger forests by planting trees capable of greater carbon sequestering.
Many areas that rely on the lumber industry have passed reforestation laws. For example, in Oregon, the law requires that logged trees be replaced with seedlings within two years and that the seedlings must be left to grow for at least six years. This plan and others like it help offset the environmental damage and also insures the future of the lumber industry. Government agencies that enforce reforestation laws often provide guidance and advice to landowners to help them comply with the law and to improve the quality of the environment.
Charitable organizations lead the way in reforestation efforts, not only in large forests but also in urban areas. The Greening of Detroit is a not for profit organization attempting to repair the damage done to trees by Dutch elm disease, urban development, and other causes. The charity encourages planting trees and rejuvenating parks and public areas. The organization involves both individuals and groups to plant young trees and to teach children about the importance of nature. Similar charities exist throughout the world, encouraging reforestation efforts and Environmental responsibility