In India, forests form 23 percent of the total land area. The word ‘forest’ is derived from the Latin word ‘foris’ means ‘outside’ (may be the reference was to a village boundary or fence separating the village and the forest land).
A forest is a natural, self-sustaining community characterized by vertical structure created by presence of trees. Trees are large, generally single-stemmed, woody plants. Forest can exist in many different regions under a wide range of conditions, but all true forests share these physical characteristics.
Because a forest is a natural community, no forest is static in time. That is, because forest communities respond to outside influences, most forests are in a state of constant flux. Depending upon the systems within which forest communities exist, such factors might include rainfall, fire, wind, glaciation, seismic activity, flooding, animal activity, insulation, and so on.
At any time, a forest is a collection of past responses to outside influences and internal competitive interactions. Therefore, the present status of any forest, indeed of any natural community, reflects what has gone on before.
Use and Over Exploitation:
A forest is a biotic community predominantly of trees, shrubs and other woody vegetation, usually with a closed canopy. This invaluable renewable natural resource is beneficial to man in many ways.
The direct benefits from forests are:
(a) Fuel Wood:
Wood is used as a source of energy for cooking purpose and for keeping warm.
Wood is used for making furniture, tool-handles, railway sleepers, matches, ploughs, bridges, boats etc.
These are used for matting, flooring, baskets, ropes, rafts, cots etc.
Fruits, leaves, roots and tubers of plants and meat of forest animals form the food of forest tribes.
Mosses, ferns, insects, birds, reptiles, mammals and micro-organisms are provided shelter by forests.
Wood and Bamboo pulp are used for manufacturing paper (Newsprint, stationery, packing paper, sanitary paper)
Bamboo and wood are used in the manufacture of rayon (yarns, artificial silk-fibres)
(h) Forest Products:
Tannins, gums, drugs, spices, insecticides, waxes, honey, horns, musk, ivory, hides etc. are all provided by the flora and fauna of forests.
The indirect benefits from forests are:
(a) Conservation of Soil:
Forests prevent soil erosion by binding the soil with the network of roots of the different plants and reduce the velocity of wind and rain — which are the chief agents causing erosion.
The fertility of the soil increases due to the humus which is formed by the decay of forest litter.
(c) Reduction of Atmospheric Pollution:
By using up carbon dioxide and giving off oxygen during the process of photosynthesis, forests reduce pollution and purify the environment.
(d) Control of Climate:
Transpiration of plants increases the atmospheric humidity which affects rainfall and cools the atmosphere.
(e) Control of Water flow:
In the forests, the thick layer of humus acts like a big sponge and soaks rain water preventing run-off, thereby preventing flash-floods. Humus prevents quick evaporation of water, thereby ensuring a perennial supply of water to streams, springs and wells.
Human Interactions with Forests:
Human are indisputably a part of most forests. With the exception of extremely inaccessible forestlands, all forests present on Earth today have been influenced by human being for tens of thousands of years. In many cases, forest communities have never been without the influence of human activities.
Because of the widespread nature of human, activity in forests, it is tempting to think of human endeavor as one more outside factor influencing forest development. This approach is misleading, however, since it denies the role of self- awareness in human activity. Because human beings can understand cause and effect, and because we have amassed an increasingly deep body of knowledge about forest processes over the past ten millennia, human influences simply cannot be likened to the blind forces of nature.
Since pre-history, human beings have realized benefits from forested lands in the form of spiritual values, medicines, shelter, food, materials, fuel and more. Often, humans have sought to manipulate natural processes so as to compel forest systems to produce more of the goods and services desired by people.
Examples range from culturally modified trees and edge habitat maintained by the Haida and others in west-coastal North America to Pre-Colombian enrichment planting of Brazil nut trees in the Amazon to traditional coppice management in the English lowlands.
At times, human management has become as intensive as to become the primary set of factors under which the forest system operates. Such systems move towards the near total human control found in agricultural systems and cannot be thought of as forests in any natural sense, although they may continue to resemble forests superficially.
Deforestation is the permanent destruction of indigenous forests and woodlands. The term does not include the removal of industrial forests such as plantations of gums or pines. Deforestation has resulted in the reduction of indigenous forests to four-fifths of their pre-agricultural area.
Indigenous forests now cover 21% of the earth’s land surface. The World Resources Institute regards deforestation as one of the world’s most pressing land-use problems. The difference between forests and woodlands is that whereas in a forest the crowns of individual trees touch to form a single canopy, in woodland, trees STOW far apart, so that the canopy is open.
Of great concern is the rate at which deforestation is occurring. Currently, 12 million hectares of forests are cleared annually. Almost all of this deforestation occurs in the moist forests and open woodlands of the tropics.
At this rate all moist tropical forest could be lost by the year 2050, except for isolated areas in -Amazonia, the Zaire basin, as well as a few protected areas within reserves and parks. Some countries such as Ivory Coast, Nigeria, Costa Rica, and Sri Lanka are likely to lose all their tropical forests by the year 2010 if no conservation steps are taken.
The destruction of forests due to unscrupulous and indiscriminate felling of trees has lead to an overall deterioration of our environment and is posing a serious threat to the quality of “life in future. Forest area in world has dwindled from 7,000 million hectares (year 1900) to 2S90 million hectares (year 1975). It is expected to further reduce to 2300 million hectares by year 2010 AD if the present trend of deforestation is not reversed.
Causes of Deforestation:
(1) Population Explosion:
Population explosion poses a grave threat to the environment. Vast areas of forest land are cleared of trees to reclaim land for human settlements (factories, agriculture, housing, roads, railway tracks etc.) growth of population increases the demand for forest products like timber, firewood, paper and other valuable products of industrial importance, all necessitating felling of trees.
(2) Forest Fires:
Fires in the forests may be due to natural calamities or human activities:
(a) Smoldering of the humus and organic matter forming a thick cover over the forest floor (i.e. ground fires).
(b) Dried twigs and leaves may catch fire (i.e. surface fires).
(c) In densely populated forests, tree tops may catch fire by heat produced by constant rubbing against each other (i.e. crown fires).
(d) Human activities like clearing forest for habitation, agriculture, firewood, construction of roads, railway tracks and carelessness (throwing burning cigarette stubbs on dried foliage).
Fire destroys fully grown trees, results in killing and scorching of the seeds, humus, ground flora and animal life.
(3) Grazing Animals:
Trampling of the forest soil in the course of overgrazing by livestock has four reaching effects such as loss of porosity of soil, soil erosion and desertification of the previously fertile forest area.
(4) Pest Attack:
Forest pests like insects etc. destroy trees by eating up the leaves, boring into shoots and by spreading diseases.
(5) Natural Forces:
Floods, storms, snow, lightening etc. are the natural forces which damage forests.
Effects of Deforestation:
Forests are closely related with climatic change, biological diversity, wild animals, crops, medicinal plants etc.
Large scale deforestation has many far-reaching consequences:
(a) Habitat destruction of wild animals (tree-using animals are deprived of food and shelter.)
(b) Increased soil erosion due to reduction of vegetation cover.
(c) Reduction in the oxygen liberated by plants through photosynthesis.
(d) Increase in pollution due to burning of wood and due to reduction in Car- bon-dioxide fixation by plants.
(e) Decrease in availability of forest products.
(f) Loss of cultural diversity
(g) Loss of Biodiversity
(h) Scarcity of fuel wood and deterioration in economy and quality of life of people residing near forests.
(i) Lowering of the water table due to more run-off and thereby increased use of the underground water increases the frequency of droughts.
(j) Rise in Carbon dioxide level has resulted in increased thermal level of earth which in turn results in melting of ice caps and glaciers and consequent flooding of coastal areas.