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CONTENTS;1. Types of forest
2. Information
3. Temperate needle
leaf
4. Temperate broad
leaf and mixed
5. Tropical moist
6. Tropical dry
7. Sparse trees and
parkland
8. Tropical forest
types

TYPES OF FOREST
1 Temperate
needleleaf
2 Temperate
broadleaf and mixed
3 Tropical moist
4 Tropical dry
5 Sparse trees and
parkland
6 Tropical forest
types
.

TEMPERATE NEEDLE LEAF
Temperate needleleaf forests mostly occupy the
higher latitude regions of the northern
hemisphere, as well as high altitude zones and
some warm temperate areas, especially on
nutrient-poor or otherwise unfavourable soils.
These forests are composed entirely, or nearly
so, of coniferous species (Coniferophyta). In the
Northern Hemisphere pines Pinus, spruces
Picea, larches Larix, firs Abies, Douglas firs
Pseudotsuga and hemlocks Tsuga, make up the
canopy, but other taxa are also important. In the
Southern Hemisphere, most coniferous trees
(members of the Araucariaceae and
Podocarpaceae) occur in mixtures with broadleaf
species, and are classed as broadleaf and mixed
forests.

Temperate broadleaf and mixed
Temperate broadleaf and mixed forests include a substantial
component of trees in the Anthophyta. They are generally
characteristic of the warmer temperate latitudes, but extend
to cool temperate ones, particularly in the southern
hemisphere. They include such forest types as the mixed
deciduous forests of the United States and their counterparts
in China and Japan, the broadleaf evergreen rainforests of
Japan, Chile and Tasmania, the sclerophyllous forests of
Australia, central Chile, the Mediterranean and California,
and the southern beech Nothofagus forests of Chile and
New Zealand

Tropical moist
There are many different types of
tropical moist forests,although
most extensive are the lowland
evergreen broad leaf rainforests,
for example várzea and igapó
forests and the terra firma forests
of the Amazon Basin; the peat
swamp forests, dipterocarp forests
of Southeast Asia; and the high
forests of the Congo Basin.
Forests located on mountains are
also included in this category,
divided largely into upper and
lower montane formations on the
basis of the variation of
physiognomy corresponding to

Tropical dry
Tropical dry forests are characteristic of areas in
the tropics affected by seasonal drought. The
seasonality of rainfall is usually reflected in the
deciduousness of the forest canopy, with most
trees being leafless for several months of the
year. However, under some conditions, e.g. less
fertile soils or less predictable drought regimes,
the proportion of evergreen species increases
and the forests are characterised as
"sclerophyllous". Thorn forest, a dense forest of
low stature with a high frequency of thorny or
spiny species, is found where drought is
prolonged, and especially where grazing
animals are plentiful. On very poor soils, and
especially where fire is a recurrent
phenomenon, woody savannas develop (see

Sparse trees and parkland
sparse trees and parkland are forests with open
canopies of 10–30% crown cover. They occur
principally in areas of transition from forested to
non-forested landscapes. The two major zones
in which these ecosystems occur are in the
boreal region and in the seasonally dry tropics.
At high latitudes, north of the main zone of
boreal forest or taiga, growing conditions are
not adequate to maintain a continuous closed
forest cover, so tree cover is both sparse and
discontinuous. This vegetation is variously
called open taiga, open lichen woodland, and
forest tundra. It is species-poor, has high
bryophyte cover, and is frequently affected by
fire.

Tropical forest types
Lowland evergreen broadleaf rain forest – Natural forests with > 30%
canopy cover, below 1,200 m (3,937 ft) altitude that display little or no
seasonality, the canopy being >75% evergreen broadleaf.
Lower montane forest – Natural forests with > 30% canopy cover,
between 1200–1800 m altitude, with any seasonality regime and leaf
type mixture.
Upper montane forest – Natural forests with > 30% canopy cover,
above 1,800 m (5,906 ft) altitude, with any seasonality regime and leaf
type mixture.
Freshwater swamp forest – Natural forests with > 30% canopy cover,
below 1,200 m (3,937 ft) altitude, composed of trees with any mixture
of leaf type and seasonality, but in which the predominant
environmental characteristic is a waterlogged soil.
Semi-evergreen moist broadleaf forest – Natural forests with > 30%
canopy cover, below 1,200 m (3,937 ft) altitude in which between 50–
75% of the canopy is evergreen, > 75% are broadleaves, and the
trees display seasonality of flowering and fruiting.

•Mixed broadleaf/needleleaf forest – Natural forests with > 30% canopy cover,
below 1,200 m (3,937 ft) altitude, in which the canopy is composed of a more or
less even mixture of needleleaf and broadleaf crowns (between 50:50% and
25:75%).
•Needleleaf forest – Natural forest with > 30% canopy cover, below 1,200 m
(3,937 ft) altitude, in which the canopy is predominantly (> 75%) needleleaf.
•Mangroves – Natural forests with > 30% canopy cover, composed of species of
mangrove tree, generally along coasts in or near brackish or seawater.
•Deciduous/semi-deciduous broadleaf forest – Natural forests with > 30% canopy
cover, below 1,200 m (3,937 ft) altitude in which between 50–100% of the canopy is
deciduous and broadleaves predominate (> 75% of canopy cover).
•Sclerophyllous dry forest – Natural forests with > 30% canopy cover, below
1,200 m (3,937 ft) altitude, in which the canopy is mainly composed of
sclerophyllous broadleaves and is > 75% evergreen.

•Thorn forest – Natural forests with > 30% canopy
cover, below 1,200 m (3,937 ft) altitude, in which the
canopy is mainly composed of deciduous trees with
thorns and succulent phanerophytes with thorns may be
frequent.
•Sparse trees and parkland – Natural forests in which
the tree canopy cover is between 10–30%, such as in
the savannah regions of the world. Trees of any type
(e.g., needleleaf, broadleaf, palms).
•Disturbed natural forest – Any forest type above that
has in its interior significant areas of disturbance by
people, including clearing, felling for wood extraction,
anthropogenic fires, road construction, etc.
•Exotic species plantation – Intensively managed
forests with > 30% canopy cover, which have been
planted by people with species not naturally occurring in
that country.
•Native species plantation – Intensively managed
forests with > 30% canopy cover, which have been
planted by people with species that occur naturally in
that country.

Reforestation
Reforestation is the natural or intentional
restocking of existing forests and
woodlands that have been depleted,
usually through deforestation.[1]
Reforestation can be used to improve the
quality of human life by soaking up
pollution and dust from the air, rebuild
natural habitats and ecosystems, mitigate
global warming since forests facilitate
biosequestration of atmospheric carbon
dioxide, and harvest for resources,
particularly timber.

Contents
•1 Management
•2 For harvesting
•3 For climate change mitigation
•4 Incentives
•5 Examples

Management
Reforestation of large areas can be done through the use
of measuring rope (for accurate plant spacing) and
dibbers, (or wheeled augers for planting the larger trees)
for making the hole in which a seedling or plant can be
inserted. Indigenous soil inoculants (e.g., Laccaria bicolor)
can optionally be used to increase survival rates in hardy
environments.
A debatable issue in managed reforestation is whether or
not the succeeding forest will have the same biodiversity
as the original forest. If the forest is replaced with only
one species of tree and all other vegetation is prevented
from growing back, a monoculture forest similar to
agricultural crops would be the result. However, most
reforestation involves the planting of different feedlots of
seedlings taken from the area often of multiple species.
Another important factor is the natural regeneration of a
wide variety of plant and animal species that can occur
on a clear cut. In some areas the suppression of forest
fires for hundreds of years has resulted in large single
aged and single species forest stands. The logging of small
clear cuts and or prescribed burning, actually increases
the biodiversity in these areas by creating a greater
variety of tree stand ages and species.

For harvesting
Reforestation need not be only used for recovery of accidentally
destroyed forests. In some countries, such as Finland, the forests are
managed by the wood products and pulp and paper industry. In such an
arrangement, like other crops, trees are replanted wherever they are
cut. In such circumstances, the industry can cut the trees in a way to
allow easier reforestation. The wood products industry systematically
replaces many of the trees it cuts, employing large numbers of summer
workers for tree planting work. For example, in 2010, Weyerhaeuser
reported planting 50 million seedlings.[3]
In just 20 years, a teak plantation in Costa Rica can produce up to about
400 m of wood per hectare. As the natural teak forests of Asia become
more scarce or difficult to obtain, the prices commanded by plantationgrown teak grow higher every year. Other species such as mahogany
grow slower than teak in Tropical America but are also extremely
valuable. Faster growers include pine, eucalyptus, and Gmelina.[4]

. Other species such as mahogany grow slower than
teak in Tropical America but are also extremely
valuable. Faster growers include pine, eucalyptus,
and Gmelina.[4]
Reforestation, if several native species are used,
can provide other benefits in addition to financial
returns, including restoration of the soil,
rejuvenation of local flora and fauna, and the
capturing and sequestering of 38 tons of carbon
dioxide per hectare per year.[5]
The reestablishment of forests is not just simple
tree planting. Forests are made up of a diversity of
species and they build dead organic matter into
soils over time. A major tree-planting program in a
place like this would enhance the local climate and
reduce the demands of burning large amounts of
fossil fuels for cooling in the summer.

For climate change
mitigation
Forests are an important part of the global carbon cycle
because trees and plants absorb carbon dioxide through
photosynthesis. By removing this greenhouse gas from the
air, forests function as terrestrial carbon sinks, meaning they
store large amounts of carbon. At any time, forests account
for as much as double the amount of carbon in the
atmosphere.[7]:1456 Even as more anthropogenic carbon is
produced, forests remove around three billion tons of
anthropogenic carbon every year. This amounts to about
30% of all carbon dioxide emissions from fossil fuels.
Therefore, an increase in the overall forest cover around the
world would tend to mitigate global warming.
There are four major strategies available to mitigate carbon
emissions through forestry activities: increase the amount
of forested land through a reforestation process; increase
the carbon density of existing forests at a stand and
landscape scale; expand the use of forest products that will
sustainably replace fossil-fuel emissions; and reduce carbon
emissions that are caused from deforestation and
degradation.[7]:1456

Achieving the first strategy would require
enormous and wide-ranging efforts.
However, there are many organizations
around the world that encourage treeplanting as a way to offset carbon emissions
for the express purpose of fighting climate
change. For example, in China, the Jane
Goodall Institute, through their Shanghai
Roots & Shoots division, launched the
Million Tree Project in Kulun Qi, Inner
Mongolia to plant one million trees to stop
desertification and help curb climate
change.[8][9] China has used 24 billion
metres squared of new forest plantation
and natural forest regrowth to offset 21% of
Chinese fossil fuel emissions in 2000[7]:1456.
In Java, Indonesia each newlywed couple is
to give whoever is sermonizing their wedding
5 seedlings to combat global warming. Each
couple that wishes to have a divorce has to
give 25 seedlings to whoever divorces
them.[10]

The second stategy has to do with selecting species for treeplanting. In theory, planting any kind of tree to produce more
forest cover would absorb more carbon dioxide from the
atmosphere. On the other hand, a genetically modified tree
specimen might grow much faster than any other regular
tree.[11]:93 Some of these trees are already being developed in
the lumber and biofuel industries. These fast-growing trees
would not only be planted for those industries but they can
also be planted to help absorb carbon dioxide faster than slowgrowing trees.[11]:93
Extensive forest resources placed anywhere in the world will
not always have the same impact. For example, large
reforestation programs in boreal or subarctic regions have a
limited impact on climate mitigation. This is because it
substitutes a bright snow-dominated region that reflects the
sunlight with dark forest canopies. A study from the National
Center for Atmospheric Research in Boulder, Colorado, USA,
found that trees in temperate latitudes have a net warming
effect on the atmosphere. The heat that dark leaves release
without absorbing outweighs the carbon they sequester.[12] On
the other hand, a positive example would be reforestation
projects in tropical regions, which would lead to a positive
biophysical change such as the formation of clouds. These
clouds would then reflect the sunlight, creating a positive
impact on climate mitigation.[7]:1457

There is an advantage to planting trees in tropical
climates with wet seasons. In such a setting, trees
have a quicker growth rate because they can grow
year-round. Trees in tropical climates have, on
average, larger, brighter, and more abundant
leaves than non-tropical climates. A study of the
girth of 70,000 trees across Africa has shown that
tropical forests are soaking up more carbon dioxide
pollution than previously realized. The research
suggests almost one fifth of fossil fuel emissions
are absorbed by forests across Africa, Amazonia
and Asia. Simon Lewis, a climate expert at the
University of Leeds, who led the study, said:
"Tropical forest trees are absorbing about 18% of
the carbon dioxide added to the atmosphere each
year from burning fossil fuels, substantially
buffering the rate of change."[13]
It is also important to deal with the rate of
deforestation. At this point, there are 13 billion
metres squared of tropical regions that are
deforested every year. There is potential for
these regions to reduce rates of deforestation
by 50% by 2050, which would be a huge
contribution to stabilize the global climate.

Incentives
Some incentives for reforestation can be as simple as a financial
compensation. Streck and Scholz (2006) explain how a group of scientists
from various institutions have developed a compensated reduction of
deforestation approach which would reward developing countries that
disrupt any further act of deforestation. Countries that participate and take
the option to reduce their emissions from deforestation during a
committed period of time would receive financial compensation for the
carbon dioxide emissions that they avoided.[14]:875 To raise the payments,
the host country would issue government bonds or negotiate some kind of
loan with a financial institution that would want to take part in the
compensation promised to the other country. The funds received by the
country could be invested to help find alternatives to the extensive
cutdown of forests. This whole process of cutting emissions would be
voluntary, but once the country has agreed to lower their emissions they
would be obligated to reduce their emissions. However, if a country was
not able to meet their obligation, their target would get added to their next
commitment period. The authors of these proposals see this as a solely
government-to-government agreement; private entities would not
participate in the compensation trades.[14]:876

Examples
Forest regrowth in Mount Baker-Snoqualmie National Forest, Washington state, USA
It is the stated goal of the US Forest Service to manage forest resources sustainably. This includes
reforestation after timber harvest, among other programs.[15]
In Germany, reforestation is required as part of the federal forest law. 31% of Germany is forested, according
to the second forest inventory of 2001–2003. The size of the forest area in Germany increased between the
first and the second forest inventory due to forestation of degenerated bogs and agricultural areas.
In China, extensive replanting programs have existed since the 1970s. Programs have had overall success.
The forest cover has increased from 12% of China's land area to 16%. However, specific programs have had
limited success. The "Green Wall of China", an attempt to limit the expansion of the Gobi Desert is planned
to be 2,800 miles (4,500 km) long and to be completed in 2050. In Canada, overall forest cover is increasing
over the last decades.
In Borneo Dr Willie Smits, bought up nearly 2000 ha of deforested degraded land in East Kalimantan that had
suffered from mechanical logging, drought and severe fires and was covered in alang-alang grass. In a project
called Samboja Lestari an area was reforested.
The Groasis Waterbox was designed specifically to establish trees in areas undergoing desertification. It
collects dew and infrequent rain, and slowly releases it to the plants roots, promoting deeper root
growth.[17]

Deforestation
From Wikipedia, the free encyclopedia
For other uses, see Deforestation (disambiguation).

Satellite photograph of deforestation in progress in the Tierras Bajas
project in eastern Bolivia.
Deforestation, clearance or clearing is the removal of a forest or stand
of trees where the land is thereafter converted to a non-forest use.[1]
Examples of deforestation include conversion of forestland to farms,
ranches, or urban use.

Class 7 science project

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