CAUSES OF FOREST FIRES IN INDONESIA
Many land clearing by burning is the leading cause of forest and land fires. But not only that the cause of the fire, there are many other factors that make land and forest to burn. The cause of the fire can be intentional or unintentional. Enormous human role in managing the natural environment that creates the cause of forest fires.
One of the things that is often blamed for prolonged droughts due to the impact of El Nino so that the land becomes dry. Natural dry conditions facilitate the expansion of forest fire very quickly.
The opening of the road through the forest made by the government and private entrepreneurs towards facilitating access to parts of the forest that was once difficult to reach. Easy access to the forest gives a fresh breeze to the forest encroachers open up new land for farming and gardening. The traditional way of clearing land by burning finally done by these people.
Deforestation for the purpose of industrial wood timber or by reason of the opening of plantations by large capital entrepreneurs, both legal and illegal. Logging followed also by the community to meet immediate economic needs.
Utilization and conversion of land that was once tropical rainforest humid, reduced humidity. Ability to store rainwater that falls seep into the soil is also reduced due to the low levels of tree density. If the felled trees on peat forest, sunlight can enter directly into the forest floor. The more extensive the larger cutting area hiatus created. Peatland from drying out and is the fuel that sparked forest fires and land. Forests in Sumatra and Kalimantan are the areas that are burned each year.
Rapid increase in the number of people making the finding and opening new lands settlement. Target is a forest that has not been inhabited by people. The rivalry between the settlers and the natives sometimes cause social jealousy. The success of the efforts of migrant communities in the process of land to make the natives feel unrivaled. The actions of other people's land burning may occur due to a sense of dissatisfaction.
Those are some of the causes of land and forest fires in Indonesia. Preventive efforts need to be done rather than the actions of forest fire extinguish itself at a cost and greater losses. Control measures requires the intervention of all parties to get involved in addressing the causes of forest and land fires.
WHAT IS FORESTRY ???
Forestry is the science of understanding to manage forest resources for the benefit of man. Forestry practices to help maintain an adequate supply of wood for timber, plywood, paper, and other wood products. In addition, understanding the value of forestry include managing forest resources such as water, wildlife, grazing areas, and recreational areas.
In general, the forest provides maximum benefit when administered with the goal of providing multiple benefits at once. This concept is called "multiple use forest management" or forest management with multiple benefits. In addition to producing lumber, forests can provide clean water for people, food and shelter for wildlife; land livestock grazing, and recreation for campers, hikers, and picnics.
Each person has different interests in forests. For example, a company that manufactures wood products primarily manage their forests for commercial timber production. Or forests can be protected as a protected area and conservation area.
Countries that have forests have one government agency to manage the forest lands and conducting research.
PLANT HORMONES
Plant hormones are produced mainly in actively growing parts, such as the tips of roots and stems. These hormones influence growth and are often called growth regulators. There are three main types of plant hormones: (1) auxins, (2) cytokinins, and (3) gibberellins.
Auxins cause various effects on different parts of a plant. In stems and roots, auxins regulate the elongation (lengthening) of cells. By stimulating cell elongation, auxins affect the manner in which stems bend toward light and away from gravity. Auxins also control the process by which roots bend toward gravity, but they do so by preventing the elongation of cells.
In many plants, auxins secreted by the bud at the tip of a stem prevent lower buds on the stem from growing. Thus, they slow the growth of side branches. Such branches could use up energy a plant needs to grow tall and sturdy. Auxins also stimulate the growth of fruit and prevent fruit and leaves from falling off a plant.
Cytokinins control cell division in plants. They apparently work together with other growth regulators, especially auxins. Cytokinins play an important role in determining which cells of a young plant will become root cells, which cells will become leaf cells, and so on.
Gibberellins stimulate many plants to grow larger. When used in experiments, they have made the stems of dwarf plants lengthen rapidly. Gibberellins also help regulate blossoming in certain plants. They cause the seeds and buds of many species to begin growing after dormancy (long periods of inactivity).
Other growth regulators include abscisic acid and ethylene. Abscisic acid blocks plant growth, thus stimulating dormancy. Ethylene regulates, among other things, the ripening of fruit.
ELIMINATING SMOKE DOES NOT NECESSARILY CUT CARBON EMISSIONS
Land-clearing techniques exist that do not produce smoke, including biological methods to accelerate decomposition and various mechanical techniques that chip or shred biomass, either for mulching on the site or for transport off site for disposal or sale. All of these `no-burn' techniques presently are more expensive than burning. Moreover, as noted above, burning produces many benefits for land users.
Research may be able to reduce the economic and technical disadvantages (compared to burning) of certain techniques, such as mulching. If they are feasible, policies to regulate the timing of burning and new techniques for land clearing without burning could-over time- address part of the regional smoke problem.
However, it must be emphasized that unless a significant portion of the biomass from land clearing is used to manufacture wood products with a long useful life (instead of simply decaying), these measures will only have a short-term effect on C emissions.
Moreover, the attractiveness of technological alternatives to clear land without burning, or the level of subsidies required for adoption of these techniques, also are infuenced by national policies, such as timber export taxes.
PROTECTING ENDANGERED SPECIES
Laws and conservation programs are helping to reduce endangerment
worldwide. In the United States, the Endangered Species Act of 1973
protects endangered and threatened wildlife and plants from hunting,
collecting, and other activities that harm them or their habitats. Since
this law was enacted, the numbers of certain endangered animals, such
as the alligator, bald eagle, and peregrine falcon, have increased so
much that they have been removed from the endangered list or
reclassified from endangered to threatened status.
Many wild species are protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This treaty, drawn up in 1973, aims to control trade in wild animals and plants, their parts, and products derived from them. Over 150 countries have joined the treaty. CITES bans trade in rhinoceros horn, cheetah fur, sea turtle shells and meat, and certain whale products. Elephant ivory was banned in 1989, but a 1997 decision enabled the African nations of Botswana, Namibia, and Zimbabwe to export a limited amount of stockpiled ivory to Japan. The ivory from these three nations was auctioned to Japanese buyers in 1999.
Various organizations publish lists of endangered species to improve public awareness. The IUCN (International Union for the Conservation of Nature and Natural Resources) compiles lists that include thousands of animal and plant species that are threatened or endangered.
Protecting habitat is the key method of preserving endangered species. Many governments and organizations have set aside nature preserves. Some zoos and animal research centers conduct programs that breed endangered species in hopes of returning their offspring to the wild. The programs have greatly improved the outlook for such endangered species as the black-footed ferret and the California condor.
Many wild species are protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This treaty, drawn up in 1973, aims to control trade in wild animals and plants, their parts, and products derived from them. Over 150 countries have joined the treaty. CITES bans trade in rhinoceros horn, cheetah fur, sea turtle shells and meat, and certain whale products. Elephant ivory was banned in 1989, but a 1997 decision enabled the African nations of Botswana, Namibia, and Zimbabwe to export a limited amount of stockpiled ivory to Japan. The ivory from these three nations was auctioned to Japanese buyers in 1999.
Various organizations publish lists of endangered species to improve public awareness. The IUCN (International Union for the Conservation of Nature and Natural Resources) compiles lists that include thousands of animal and plant species that are threatened or endangered.
Protecting habitat is the key method of preserving endangered species. Many governments and organizations have set aside nature preserves. Some zoos and animal research centers conduct programs that breed endangered species in hopes of returning their offspring to the wild. The programs have greatly improved the outlook for such endangered species as the black-footed ferret and the California condor.
ENDANGERED SPECIES
Endangered species are living things threatened with extinction-that is, the dying off of all of their kind. Thousands of species of animals and plants are endangered, and the number increases each year. Some examples of endangered species are blue whales, giant pandas, orangutans, rhinoceroses, sea turtles, snow leopards, tigers, and whooping cranes. Among endangered plants are running buffalo clover, Santa Cruz cypress, snakeroot, and many species of cactuses.
Each species of plant and animal plays a part in the delicate balance of its ecosystem, its relation to other living things and the environment. Thus, the extinction of large numbers of species threatens the survival of other living things, including human beings. As more species have become endangered, ecosystems have become unstable or collapsed. Fortunately, people have increased their efforts to protect endangered species.
Most biologists consider a species endangered if they expect it would die off completely in less than 20 years if no special efforts were made to protect it, or if the rate of decline far exceeds the rate of increase. Until the last few centuries, species became rare or died out as a result of natural causes. These causes included changes in climate, catastrophic movements in the earth's crust, and volcanic eruptions.
Today, species become endangered primarily because of human activities. Species mainly become endangered because of
- loss of habitat,
- wildlife trade,
- overhunting, and
- competition with domestic and nonnative animals.
Loss of habitat
Loss of habitat poses the greatest threat to the survival of wild species. Most animals and plants are specially adapted to live and reproduce in a specific environment or habitat and cannot survive when it is destroyed. The destruction of virgin forests by loggers and settlers and the conversion of natural grasslands into pasture for livestock have eliminated vast expanses of wildlife habitats. Marshlands have been drained for farmland and building projects. Coral reefs and many marine environments have become polluted, overfished, and even dynamited to obtain tropical fish and corals. Tropical rain forests contain the greatest variety of animal and plant life on earth, and they are being destroyed more rapidly than any other type of wild habitat.
Wildlife trade
Wildlife trade involves the capture of animals for pets, zoo specimens, and research subjects, and the killing of animals for their fur or other body parts. The capture of wild animals for commercial use has endangered many species. For example, the Spix's macaw, a parrot of Brazil, is nearly extinct in the wild because so many have been captured for private bird collectors. Many primates, including the orangutan, have become endangered by the illegal killing of the mothers to capture their babies for zoos and pet dealers. Gorillas, chimpanzees, and other primates are killed for their meat, which is sold in African markets.
Other animals have been killed in such large numbers for their fur, hides, tusks, or horns that they are nearly extinct. Rhinoceroses, wild chinchillas, the Tibetan antelope, and snow leopards are among these. Although such animals are now protected by law in the countries where they live, they are still poached (hunted illegally). Poaching also has seriously reduced the number of African elephants.
Overhunting
Overhunting has brought numerous species to the brink of extinction. The Caribbean manatee, the Asiatic lion, the dugong, and many species of pheasants have become endangered because people have hunted them for food and trophies. Many species are killed by people who believe that the animals threaten their livelihoods. Livestock owners, for example, may shoot, trap, or poison wild animals that they consider a danger to their herds. Farmers and ranchers in North America have nearly eliminated the red wolf and many species of prairie dogs, while herders in Africa have almost wiped out the Simian Wolf. Some people in the fishing industry blame seals, which eat fish, for reductions in their catch. Fishing crews have killed so many Mediterranean monk seals that fewer than 200 survive.
Competition
Competition with domestic and nonnative animals is a major threat to numerous plants and animals. On many islands, native birds, mammals, and reptiles have become endangered after people introduced domestic animals. Livestock overgraze vegetation, eliminating habitat. Domestic cats prey on birds and small mammals. Rats escape from ships and infest islands, killing small birds and their eggs. In mainland areas, stocking of game fish threatens native fish, and nonnative plants and animals crowd out many native species.
THE EFFECTS OF SLASHING DAN BURNING OF LAND MANAGEMENT
Slashing and burning is the preferred method of land clearing in the tropics for smallholders and large companies alike because it is cheaper, at least from a private perspective, and easier than available alternatives. In addition, fire eliminates field debris, reduces problems with weeds and other pests and diseases, makes nutrients available in the form of ash and loosens the soil to make planting easier. In some ways it is preferable environmentally compared to some other land-clearing methods.
For example, bulldozers and other heavy machinery cause soil compaction and erosion. Fire has many distinct advantages for low-income households: all other methods are more expensive; fire kills crop pests and diseases; and the ash provides much-needed fertilizer. Results of field experiments and surveys in Sumatra Indonesia demonstrate the key role that phosphorus (P) plays in resource management. Burning at low or medium intensity releases P into soil solution, but high-intensity fires reduce P levels. With greater fuel supply, hence hotter fires, the negative effects of heat on soil mineralogy offset the positive effects of additional ash.
DEFINITION AND UNDERSTANDING OF ECOSYSTEM MANAGEMENT
Definition and Understanding of Ecosystem Management is a confusing mixture of good forest ecology principles and integrated or multiple use forest management. Advocates of ecosystem management analyze and describe ecosystem functioning in ways that recognize the need to maintain natural composition and structures of forest ecosystems from the landscape level to the stand or patch level.
However, while providing good information about forest functioning, practitioners of ecosystem management also continue to advocate methods and levels of timber extraction that degrade forest ecosystem composition, structures, and functioning necessary to maintain fully functioning forests through time. Conventional clearcutting and tree plantations are regular components of ecosystem management.
In contrast, ecologically responsible timber management is ecosystem-based, which means that the character (i.e. composition, structure, and functioning) and condition of ecosystems determine what types of human use can be carried out and in what ways and at what level of intensity these uses can occur while ensuring the maintenance of fully functioning forests at all scales through time.
Conventional timber management approaches described above all utilize concepts oriented to exploiting natural forests for timber and to producing crops of trees in short time cycles. Most of these concepts have little or no application in ecologically responsible timber management, because conventional approaches are focused on timber, while ecosystembased, ecologically responsible approaches are focused on forests.
However, while providing good information about forest functioning, practitioners of ecosystem management also continue to advocate methods and levels of timber extraction that degrade forest ecosystem composition, structures, and functioning necessary to maintain fully functioning forests through time. Conventional clearcutting and tree plantations are regular components of ecosystem management.
In contrast, ecologically responsible timber management is ecosystem-based, which means that the character (i.e. composition, structure, and functioning) and condition of ecosystems determine what types of human use can be carried out and in what ways and at what level of intensity these uses can occur while ensuring the maintenance of fully functioning forests at all scales through time.
Conventional timber management approaches described above all utilize concepts oriented to exploiting natural forests for timber and to producing crops of trees in short time cycles. Most of these concepts have little or no application in ecologically responsible timber management, because conventional approaches are focused on timber, while ecosystembased, ecologically responsible approaches are focused on forests.
UNDERSTANDING MULTIPLE USE FOREST MANAGEMENT
Understanding Multiple Use Forest Management is a system of forestry or timber management that assumes that a full spectrum of forest uses, from timber cutting and tourism to water production and nontimber forest products, can occur simultaneously throughout a forest landscape. When practiced across relatively large areas (500,000 hectares/1.2 million acres and larger), multiple use appears to work for a period of time.
However, under this regime, all forest stands with merchantable and economically accessible timber are planned for eventual timber cutting. Thus, as logging progresses through the landscape, both forest functioning and non-timber forest uses are progressively degraded.
Proponents of multiple use often attempt to convince other forest users that tree plantations are forests, and that society cannot afford to protect animals, plants, and microorganisms that stand in the way of economic growth. An ecosystem-based perspective maintains that human societies cannot afford not to protect forest functioning and maintain diverse forest uses that are the foundation for stable local economies.
DEFINITION OF SUSTAINED YIELD FORESTRY
Definiton of Sustained yield forestry is a concept that designs timber cutting and regrowing of timber crops to provide a perpetual yield of timber from a particular forest landscape. Initially, this concept embodied the commitment to non-declining timber yields over time.
However, the determination of annual cuts under sustained yield forestry has commonly been overly optimistic when considering both tree growth rates and the portion of a forest landscape that is suitable for the cutting and growing of timber crops over time. Thus, as a result, “sustained timber yields” have tended to decline through time as a result of excessive cutting rates that cannot be matched by the rate of regrowth of timber and by extraction of timber from land that subsequently proves to be unsuitable for timber growth and/or necessary to protect for non-timber forest uses.
Sustained yield forestry confuses timber or trees with forest ecosystems and fails to recognize that fully functioning forests are necessary to have trees, which are necessary to have timber. In contrast, an ecosystembased approach protects forest functioning at all scales through time as the first priority; and then seeks to sustain, within ecological limits, a diversity of human and non-human uses across the forest landscape.
DEFINITION OF FOREST STANDS | FOREST PATCHES
Definition of Forest Stands or Forest Patches refer to the ecosystem scale at which a relatively homogenous forest unit can be identified. The composition, structure, and ecological functions within a stand are similar enough that an ecologically responsible forest use prescription can be applied uniformly within the stand, without encountering changes in ecological parameters that may produce unexpected or undesirable results.
In conventional forestry, “stands” have largely been defined by narrow timber characteristics, which were in turn driven by short-term economic variables. However, in order to plan and carry out ecologically responsible forest uses within an ecosystem-based approach, stands must be defined in relation to whole ecosystem factors that are required to maintain fully functioning forests at the landscape and stand levels.
In other words, the boundaries of a stand are not determined by rigid human management criteria such as timber size and timber quality, but by the full spectrum of ecosystem parameters that have been shaped by natural disturbance patterns and that reflect the movement of energy, nutrients, water, and animals into and out of a particular ecosystem.
Human scales are closest to forest scales at the stand or patch level. For example, the stand or patch level is the scale where visible human modification occurs. However, an ecosystem-based approach must always consider that what occurs at the stand or visible scale will also have impacts on a variety of other scales, from the large landscape to the microscopic.
DEFINITION OF FOREST LANDSCAPE
d
Definition of forest landscape is the large-scale view of a forest. When industrial timber managers use the term “forest landscapes,” they are usually concerned with scenery and visual impacts. In the context of an ecosystem-based approach, however, a forest landscape is a mosaic of interconnected, interdependent stands or patches that are repeated in a pattern across the larger landscape. This pattern has both spatial and temporal components.
An ecosystem-based approach requires that all planning and activities begin at the regional/landscape level. When planning for human use, landscape level decisions are made for watersheds of small to moderate size (less than 5,000 hectares to about 50,000 hectares, or 12,000 to 125,000 acres). In sub-regional or regional planning processes, forest landscape level considerations are expanded to large watersheds encompassing hundreds of thousands of hectares/acres.
In planning and carrying out forest uses, particularly timber management, many people tend to focus on small forest parcels. This is a result of our limited spatial view, short time frames, and cultural conditioning. In contrast, an ecosystem-based approach requires that all planning and activities start at the landscape level. The character and condition of the forest landscape dictate what is ecologically possible at the stand level.
The character of a forest ecosystem refers to how a forest works, from the landscape level to the stand or patch. For example, forests that have frequent fires have a different character than forests where wind and root decay are the primary agents of disturbance. Some forests are characterized by steep slopes, shallow soils, and well-defined drainage patterns, while other forests have gentle slopes, cold soils, and diffuse drainage patterns.
Forests of a different character will have different composition and structures, and therefore differences in how they function. Different composition, structures, and functioning lead to different kinds of ecological limits to human use. Ecological limits are natural factors or processes that are easily damaged or degraded if modified by human uses. For example, steep and/or wet slopes impose ecological limits because, if disturbed, they are likely to erode, causing problems like soil loss and siltation of streams. Cold soils are an ecological limit because nutrient cycling occurs in shallow organic layers which may be easily damaged by many types of human activities.
The condition of a forest describes how human uses have modified forest functioning from the landscape level to the stand or patch level. Conventional timber management frequently results in negative impacts, like fragmentation, loss of old growth, and soil degradation. An ecosystem-based approach protects forest composition and structure and respects the ecological limits of forests to various human uses. By respecting ecological limits ecosystem-based approaches avoid degradation of short- and long-term forest functioning.
Ecological limits to human use are determined by describing and interpreting the character and condition of, first, the forest landscape, and then the forest stand or patch.
Definition of forest landscape is the large-scale view of a forest. When industrial timber managers use the term “forest landscapes,” they are usually concerned with scenery and visual impacts. In the context of an ecosystem-based approach, however, a forest landscape is a mosaic of interconnected, interdependent stands or patches that are repeated in a pattern across the larger landscape. This pattern has both spatial and temporal components.
An ecosystem-based approach requires that all planning and activities begin at the regional/landscape level. When planning for human use, landscape level decisions are made for watersheds of small to moderate size (less than 5,000 hectares to about 50,000 hectares, or 12,000 to 125,000 acres). In sub-regional or regional planning processes, forest landscape level considerations are expanded to large watersheds encompassing hundreds of thousands of hectares/acres.
In planning and carrying out forest uses, particularly timber management, many people tend to focus on small forest parcels. This is a result of our limited spatial view, short time frames, and cultural conditioning. In contrast, an ecosystem-based approach requires that all planning and activities start at the landscape level. The character and condition of the forest landscape dictate what is ecologically possible at the stand level.
The character of a forest ecosystem refers to how a forest works, from the landscape level to the stand or patch. For example, forests that have frequent fires have a different character than forests where wind and root decay are the primary agents of disturbance. Some forests are characterized by steep slopes, shallow soils, and well-defined drainage patterns, while other forests have gentle slopes, cold soils, and diffuse drainage patterns.
Forests of a different character will have different composition and structures, and therefore differences in how they function. Different composition, structures, and functioning lead to different kinds of ecological limits to human use. Ecological limits are natural factors or processes that are easily damaged or degraded if modified by human uses. For example, steep and/or wet slopes impose ecological limits because, if disturbed, they are likely to erode, causing problems like soil loss and siltation of streams. Cold soils are an ecological limit because nutrient cycling occurs in shallow organic layers which may be easily damaged by many types of human activities.
The condition of a forest describes how human uses have modified forest functioning from the landscape level to the stand or patch level. Conventional timber management frequently results in negative impacts, like fragmentation, loss of old growth, and soil degradation. An ecosystem-based approach protects forest composition and structure and respects the ecological limits of forests to various human uses. By respecting ecological limits ecosystem-based approaches avoid degradation of short- and long-term forest functioning.
Ecological limits to human use are determined by describing and interpreting the character and condition of, first, the forest landscape, and then the forest stand or patch.
THE IMPACT OF THE HUMAN ACTIVITIES ON THE ECOSYSTEMS
The impact of human activities on the fundamental ecological process of the planet grows so to does the list of species and ecosystems at risk. Addressing the damage and loss requires that we understand the causes and take action based on that understanding. Underlying threats to biodiversity include the size and distribution of the human population, the level of resource consumption, programs and policies that effectively provide incentives for the depletion of biological diversity and failing to recognize the full value of environmental goods and services. While these underlying causes are often related to universal human values and are extremely complex and difficult to address, there are more direct and immediate threats that can and should be addressed at the provincial and local levels.
The immediate threats to biodiversity can be summarized under five main headings:
- habitat loss and fragmentation,
- invasive exotic species,
- pesticides and pollution,
- over-harvesting and
- global warming.
The next most serious problem is invasive exotic species. Hundreds of species have been deliberately or accidentally introduced and some have become serious threats to native species. For example, leafy spurge can completely displace native vegetation, European carp destroy the habitat of other fish and non-native ladybugs may out-compete their native counterparts. Many of these non-native species are also serious agricultural pests responsible for millions of dollars in lost revenue.
The widespread use of pesticides also poses a threat to the biodiversity. Herbicides and insecticides can kill beneficial native plants and insects. Improperly used pesticides also promote the evolution of resistance in pests, which can also reduce the long-term effectiveness of the pesticides. The combined impact of the increasing number of exotic pests and the need to control all pests highlights the need to develop more ecologically friendly and sustainable pest management tools.
Over-harvesting of game species has largely been addressed through regulations that prevent people from taking too many plants, animals, birds or fish for sport or consumption. However there is still the issue of poaching and its impact on the biodiversity. Poachers take as many animals as the people who legally hunt, fish or harvest. This means we must focus attention on dealing with those who ignore existing regulations. Not all of the harvesting pressure comes from illegal users. For example, research shows that the number of fish in a lake drops dramatically once a road is opened to the lake. Also, there are currently no regulations addressing the harvest of wild plants unless they are legally designated species at risk. The challenge facing us is balancing the need to use the resource with the need to conserve the resource.
Climate change is acting in concert with the other forces to increase the impacts on native species. For example, species' ranges expand or contract as an adaptive response to natural climate variation. As global warming continues this requirement for range movement will likely increase. However, movement of species is very difficult due to extensive habitat loss and fragmentation. It is therefore vital to re-establish or maintain linkages or corridors across ecosystems that will allow for the movement of these species and their genes.
DEFINITION GYMNOSPERM
Gymnosperm, is the name of one of two large groups of seed plants. The plants have naked, or uncovered, seeds. The term gymnosperm comes from two Greek words meaning naked and seed. The other group, called the angiosperms, consists of plants whose seeds have a protective ovary (seed case).
The gymnosperms are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and Gnetales. The term "gymnosperm" comes from the Greek word gymnospermos (γυμνόσπερμος), meaning "naked seeds", after the unenclosed condition of their seeds (called ovules in their unfertilized state). Their naked condition stands in contrast to the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, often modified to form cones, or at the end of short stalks as in (Ginkgo).
The gymnosperms and angiosperms together compose the spermatophytes or seed plants. By far the largest group of living gymnosperms is the conifers (pines, cypresses, and relatives), followed by cycads, Gnetophytes (Gnetophyta, Ephedra and Welwitschia), and Ginkgo (a single living species).
Gymnosperms are vascular seed plants that display very prominent and large bodies, mainly in evergreen tree form. During the ancient past gymnosperms dominated the landscape with their size and abundance. However, in modern times, gymnosperms are represented by less than one thousand species.
The Structure of Gymnosperm Types
Coniferophyta (Conifers) The basic body plan of conifer is that of an evergreen tree. Evergreen in the fact that most of these trees do not drop all their leaves (or in this case, needles) at once in the fall and grow them all back at once in the spring as do deciduous trees. Larches and bald cypress trees are an exception, however.
Gymnosperms are woody perennials which are among the largest and oldest living plants. There are about 800 species of gymnosperms. About 600 are conifers such as the pines, firs, spruces, and balsams. These cone-bearing trees make up the largest division (group) of gymnosperms. The tropical and subtropical cycads, also gymnosperms, are among the most primitive living seed plants. The ginkgo, also called the maidenhair tree, is another primitive gymnosperm.
Many of the gymnosperms are evergreen with a wide variety in the structure of the leaves. They do not bear flowers. Tiny male cones produce the pollen, which is usually spread by the wind. The naked, or exposed, seeds are borne between the scales of the female cones and drop when they become ripe. Gymnosperms provide the source of many valuable products such as tar, turpentine, rosin, and timber.
DEFINITION OF CONIFER - CONIFEROUS FOREST
Conifers are one of the oldest groups of woody plants. Conifer fossils have been found in rocks that are about 300 million years old. Conifers include the largest, tallest, and oldest living things. The largest giant sequoia is about 275 feet (83.8 meters) high, and the base of its trunk has a circumference of 103 feet (31.4 meters). Redwoods, the tallest living trees, may tower more than 360 feet (110 meters) high. Some bristlecone pines are more than 4,600 years old.
Conifers form about 30 per cent of the world's forests. In North America, most of the wood used in houses and other buildings comes from conifers, especially Douglas-fir and loblolly pine. Conifers also provide much wood pulp for making paper and cardboard. In addition, millions of conifers are used every year as Christmas trees.
In southern Canada the Taiga mingles with the temperate deciduous forest in some places. In northern Canada, the Taiga gradually tapers off, and the Arctic Tundra begins. The Siberian Taiga in Russia and Asia often has taller trees.
The main feature of the northern temperate zone of Asia is the presence and great importance of conifer species. Their distribution is generally restricted to the temperate zone, while summer-green broadleaved species are dominant over the whole territory. Because of high fire sensitivity, the nemoral conifers can easily disappear from the communities leaving a great question for researchers; whether the pure broadleaved forests in densely populated and severely deforested regions were originally summer-green broadleaved or whether they used to be mixed with conifers before human influence. Conifer forests in those regions occur in very small areas, as a rule – not comparable in size with the areas of broadleaved forests.
On the other hand, many conifer species are adapted to extreme edaphic conditions within the temperate zone, such as water deficit, wind exposure, nutritionally poor soils, slope processes and others.
Coniferous Forest
The Coniferous forest, located along the northern California coast, contains the largest life-form on Earth! The giant Sequoia trees are also the longest-lived life form on Earth. Some of these trees are 3,000 years old and counting!. Some coniferous trees depend on fire as a catalyst for seed-release. The Lodgepole Pine tree is an example of this kind of tree. The seeds develop in the pinecones, but unlike other conifers whose pinecones ripen and open to release the seeds, the Lodgepole's cones never ripen. The heat from naturally occurring fires force the Lodgepole Pine tree's serotinous cones to burst open, thus releasing the tree's seeds.
Temperature
-40°C to 20°C, average summer temperature is 10°CPrecipitation
300 to 900 millimeters of rain per yearVegetation
Coniferous-evergreen trees (trees that produce cones and needles; some needles remain on the trees all year long)Location
Canada, Europe, Asia, and the United StatesOther
Coniferous forest regions have cold, long, snowy winters, and warm, humid summers; well-defined seasons, at least four to six frost-free monthsMost conifers are evergreen and have small, needlelike leaves. Other conifers, including redcedars and cypresses, have tiny, scalelike leaves that cling to the stem. These trees are also evergreen. Larches and baldcypresses are conifers but they lose their leaves every year.
Conifer cones range from less than 1/2 inch (1.3 centimeters) long to more than 2 feet (61 centimeters) long. Conifers have two types of cones--male and female. In most conifers, both types grow on the same plant. The soft male cones produce and release pollen, then shrivel and die. The female cones are larger and become woody with age. Each of their scales has two structures called ovules, which contain eggs (female reproductive cells). Wind carries pollen from the male cones to the female cones, where the pollen fertilizes the egg. The ovules then develop into seeds. After the seeds become fully formed, they fall from the cones.
A few conifers have unusual, fleshy cones. Juniper seed cones resemble blueberries. Yew seed cones look like red berries with a single, large seed.
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d Definition of forest landscape is the large-scale view of a forest. When industrial timber managers use the term “forest landscapes,” th...
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Needleleaf trees include such familiar trees as firs, hemlocks, pines, redwoods, and spruces. There are about 500 species of needleleaf ...
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FUNGI DEFINITION Definition of Fungi are organisms that lack chlorophyll, the green coloring matter that many plants use to make food. F...
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In forests and other natural areas, a series of orderly changes may occur in the kinds of plants and animals that live in the area. This...
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Some leaves have special functions along with or instead of food making. Such specialized leaves include (1) protective leaves, (2) st...
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Many systems are used to classify the world's forests. Some systems classify a forest according to the characteristics of its domin...
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MYCORRHIZAL SYMBIOSIS DEFINITION The terms symbiotic and mutualistic have been used interchangeably to describe mycorrhizal associati...
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The warm, wet, and relatively aseasonal climate of the tropics is apparently more favourable for maintaining higher diversity than ...