Ground layer: sparse plant growth. Less than 1 percent of the light that strikes the top of the forest penetrates to the forest floor. In such darkness few green plants grow. The canopy above also reduces moisture: one third of the precipitation is intercepted before it reaches the ground.
Taiga
The taiga forest exists as a nearly continuous belt of coniferous trees across North America and Eurasia. Overlying formerly glacial areas, the forest is covered in plant communities sensitive to varying environmental conditions. Taiga is the Russian name for this forest, which covers so much of that country. However, the term is used in North America as well.
Climate: The taiga corresponds with regions of arctic and cold continental climate. Long, severe winters (up to six months with mean temperatures below freezing) and with short summers (50 to 100 frost-free days) are common, as is a wide range of temperatures between the lows of winter and highs of summer. For example, Verkhoyansk, Russia, has recorded extremes of minus 90°. The Mean annual precipitation is 15 to 20 inches, but low evaporation rates make this a humid climate
The conical or spire-shaped needle leaf trees common to the taiga are adapted to the cold and the physiological drought of winter and to the short-growing season:
- Conical shape - promotes shedding of snow and prevents loss of branches.
- Needle like leafs - narrowness reduces surface area through which water may be lost (transpired), especially during winter when the frozen ground prevents plants from replenishing their water supply. The needles of boreal conifers also have thick waxy coatings
- Dark colour - the dark green of spruce and fir needles helps the foliage absorb maximum heat from the sun and begin photosynthesis as early as possible.
The looks of the amazon forest are changing due to human involvement. The humans are chopping down the trees for the wood. This wood is used as fuel, building carpentry, and leaves wide-open areas inside the forest for cattle ranching. Another reason they are chopping down the trees is for transport routes, which will lead to small settlements being built, which will gradually get increase in size. But the main thing they are using it for is oil, under the amazon there is large quantities of the forest is being chopped down by multinational companies to get to the oil.
This is causing conflicts with the local tribes in the area mainly due to the fact that the forest is there home and it is being destroyed. The companies are trying to move them out but they are being unsuccessful.
The function of the forest is changing because of this human involvement. Trees are being cut down which are ruining the homes of plants and animals. This is killing the primary producers, which is in turn killing animals throughout the food chain, which could lead them to become extinct.
In the amazon forest, it is time for a managing strategy to be incorporated to stop the deforestation, which is happening at the moment. By keeping the amazon forest as it is we will be saving 1000’s of plants and animals that could be used for medical cures used to save lives, the natural beauty of the forest and the tribal homes. For every tree chopped down a new one must be planted to replace it. Also only special areas of the forest can be cut down anywhere else and it is illegal logging.