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165 Lesson 2 : Deforestation I. and Loss of Biodiversity Deforestation A. The Importance of Biodiversity Forests, grasslands, deserts, wetlands, coral reefs, and other ecosystems throughout the world are coming under increasing stress from population growth and economic development. The three components of the planet’s biodiversity are (1) genetic diversity - variability in the genetic makeup among individuals within a single species; (2) species diversity - the variety of species on earth and in different habitats of the planet, and (3) ecological diversity - the variety of forests, deserts, grasslands, streams, lakes, oceans, and other biological communities that interact with one another and with their nonliving environments (Miller, 1994). Because biodiversity is a vital part of the earth’s capital that sustains all life, preserving the planet’s genes, species, and ecosystems should be among our most important priorities. One way to do this is to protect species from sharp population declines and premature extinctions that result from human activities. However, most wildlife biologist believe that the best way to protect species diversity is to sustain and protect the earths ecosystems that serve as habitats. This means establishing a worldwide network of reserves, parks, wildlife sanctuaries, and other protected areas. Protecting these vital oases of biodiversity from damage, using them sustainably by learning how nature does this, and helping heal those we have damaged are important challenges (Miller, 1994). As of 1993, about 7,000 protected areas throughout the world, occupy 4.9 percent of the earth’s land surface. That is an important beginning, but environmentalists say that a minimum of 10 percent of the globe’s land area must be protected. Moreover, many existing reserves are too small to provide any real protection for the populations of wild species that live on them. (Miller, 1994). 166 B. Forests The forest is a focal ecosystem. Its state affects almost all other ecosystems. It plays a very crucial ecological role in soil and water conservation (Tujan, 1997). Types of Forests Old-growth forests are virgin (uncut) forests and old second-growth forests have not been seriously disturbed for several hundred years. They contain massive trees that are hundreds or even thousands of years old. The understory and other vegetation zones in old-growth forests provide ecological niches for a variety of wildlife species. These forests also have large numbers of standing dead trees (snags) and fallen logs (boles), which are habitats for a variety of species. Decay of this dead vegetation returns nutrients to the soil (Miller, 1994). Second-growth forests are stands of trees resulting from secondary ecological succession after cutting. About 40 percent of tropical forests are second-growth forests. Some old second-growth stands have remained undisturbed long enough to be classified as old-growth forests, but many are tree farms - managed tracts of uniformly aged trees of one species that are harvested as soon as they become commercially valuable (Miller, 1994). Commercial and Ecological Importance of Forests Forests give us lumber for housing, biomass for fuelwood, pulp for paper, medicines, and many other valuable products such as turpentine, nuts and fruits, and charcoal. Many forestlands are also used for mining, grazing livestock, and recreation (Miller, 1994; Miller, 1994). Forested watersheds act as giant sponges, slowing down runoff and absorbing and holding water that recharges springs, streams, and groundwater. Thus, they regulate the flow of water from mountain highlands to croplands and urban areas, and they help control soil erosion, reduce flooding, and reduce the amount of sediment washing into 167 streams, 1994). lakes, and reservoirs (Miller, 1994; Miller, Forests also influence local, regional, and global climate. For example, 50 – 80 percent of the moisture in the air above tropical forests comes from trees via transpiration and evaporation. If large areas of these lush forests are cleared, average annual precipitation drops, the regions climate gets hotter and drier, and soils become depleted of already-scarce nutrients, baked, and washed away. Eventually this process can convert a diverse tropical forest into a sparse grassland or even a desert (Miller, 1994; Miller, 1994). Forests also provide habitats for more wildlife species than any other biome, making them the planet’s major reservoir of biodiversity. They also buffer us against noise, absorb air pollutants, and nourish the human spirit. Since agriculture began about 10,000 years ago, human activities have reduced the earth’s forest cover by at least one-third, to about 34 percent of the world’s land area (Miller, 1994). Forest act as carbon sink that traps carbon dioxide released in the atmosphere. According to studies, a hectare of vegetated forests can trap a ton of carbon dioxide every year. Forests, too, can moderate local climate (Tujan, 1997). Forests serve as efficient watersheds, collecting and regulating the flow of water supply which can be tapped for household and industrial use, or agricultural irrigation. Forests prevent flash floods. They control soil erosion and water pollution. Aside from being the source of wood and water, forests also supply power. Philippine forests host one of the world’s richest plant and animal species. They are estimated to harbor about 8,120 species of flowering plants, 3,500 species of indigenous trees, 33 species of gymnosperms, 640 species of mosses, 2,400 species and sub-species of fish, around 240 species and sub-species of mammals. There are 3,000 species of plants which are endemic (i.e. found nowhere else in the world) to the Philippines. The Philippine forests also harbor around 7.1 million indigenous peoples (Tujan, 1997). 168 Depleted forests means less sources of food, medicinal plants and renewable energy, and less capacity to nurture genetic species. Degraded forests translate to erosion of otherwise productive lands, siltation and sedimentation of inland and coastal waters, among others. Cleared forests could spell the loss of home and livelihood for 18.6 million indigenous peoples and upland dwellers (Tujan, 1997). The Philippine Forests The Philippine forests are among the most diverse in the world and are also the most endangered. The state of Philippine forests is critical. Latest estimates place the country’s remaining forest areas at 5.6 million hectares from 20 million hectares a century ago. (Table 1) This forest cover is roughly 18.6 percent of the country’s total land area, and thus, far below the country’s ideal forest cover. For the Philippines to be ecologically sound and able to sustain its ecosystems, its ideal forest cover, or what is fit for its narrow, mountainous terrain, should be 54 percent of its land area (Tujan, 1997; EMB, DENR, 1994). 169 Table 3 further loses significance considering government definition of forests simply as areas of one hectare or more and at least 60 meters wide which are at least 10 percent stocked with forest trees (including seedlings and saplings), wild palms, bamboo or brush. Table 3. Change in forest land area, selected years Year Forest Cover (million hectares) 1575 1863 1920 1934 1970 1980 1990 1991 1992 1993 1994 1995 27.5 20.9 18.9 17.8 10.9 7.4 6.2 6.0 5.9 5.8 5.7 5.6 Proportion to Total Land Area (%) 92.0 70.0 64.0 57.3 36.3 24.7 20.7 20.5 19.6 19.3 18.9 18.6 Deforestation Rate (hectares/year 22,917 35,088 78,571 191,667 350,000 120,000 120,000 120,000 120,000 120,000 120,000 120,000 Source: Department of Environment and Natural Resources The Philippine forests have been steadily shrinking at an average rate of 2 percent per annum, or a relatively fast deforestation rate of 550,000 hectares per year. This rate means that every hour, 63 hectares of forests are cleared. At this rate, all our forests would be gone by the turn of the century. Because the country is an archipelago with diverse terrain, flora species also vary. Thus, the Philippine forests are further categorized into dipterocarp (66.06%), mossy (18.9%), sub-marginal (8.7%), pine (4.1%), and mangrove (2.1%) (Table 4). 170 171 Dipterocarp forests, prevalent all throughout the archipelago, are the most important type. They are the major source of timber and other forest products. They support one of the world’s richest plant and animal life, and have nurtured innumerable generations of tribal Filipinos. Philippine dipterocarp forests can either be old growth - the tropical rainforests without traces of commercial logging (sometimes known as virgin forests) - or residual - those with traces of commercial logging. Table 4 shows that there are now more residual forests than an old-growth forests, a complete reversal of the situation early this century (Tujan, 1997; EMB, DENR, 1996). Table 4 shows that in the past eight years alone, dipterocarp forests narrowed down by 24 percent, residual forests by 20 percent, and old growth by the fastest rate of 34 percent. While Table 4 shows that since 1991, the area of old growth forests has been maintained (presumably because of the government log ban policies), deforestation of old growth forests is irreversible. For every five years since 1970, the deforestation rate increased (Table 5). Table 5. Change in old-growth dipterocarp forest area Source: Year Area (in million has.) 1970 1975 1980 1985 1990 1995 5.217 3.687 2.443 1.539 0.861 0.805 Deforestation Rate 306,000 249,000 181,000 136,000 11,000 Philippine Forestry Statistics, various years On the other hand, mossy and sub-marginal forests protect watershed areas and provide a sustainable supply of water for irrigation and domestic use in the lowlands. They also protect the soil and water of wildlife feeding grounds. They are not commercially exploitable (Tujan, 1997; EMB, DENR, 1996). Still, majority of the country’s watersheds are considered bydrologically critical because of their present 172 degraded condition. Erosion of watershed areas has already reached critical proportions (Table 6). Of the 11 million hectares of critically denuded forest land, at least two million hectares are in critical watershed areas, like those of the Agno River, Pampanga River, Cagayan River, the Maga, and the Pantabangan watersheds (Tujan, 1997; EMB, DENR, 1996; Sajise, 1992). Table 6. Extent of degradation of watershed areas extended for agriculture and non-agriculture uses (in ‘000 Hectares) AGRICULTURE Moderate to Proportion Area Severe Eroded Erosion Luzon Vizayas Mindanao Philippines Source: NON-AGRICULTURE Moderate to Proportion Area Severe Eroded Erosion 5,994 1,294 5,480 1,440 501 3,868 24.0% 38.7% 70.6% 8,146 2,174 4,720 4,564 1,320 4,129 56.0% 60.7% 87.5% 12,767 5,809 45.5% 15,039 10,013 66.6% ALMED -Bureau of Soils and Water Management, 1990 Pine forests are endemic to the higher altitudes of Luzon while mangroves occur on tidal flats along the sea coast up to the streams where the water is brackish (Tujan, 1997; EMB, DENR, 1994). Forest Distribution in the Philippines No data is available that solely pins down forest destruction as the cause of soil erosion and sedimentation. However, it is estimated that deforestation-induced erosion is 100,000 hectares at one meter depth of one billion cubic meters every year (Tujan, 1997; Sajise, 1992). The Environmental Management Bureau reported in 1990 that, because of forest denudation, 22 of the country’s 173 provinces were already badly eroded. Aside from soil erosion, the capacity of the soil to hold water deteriorated with forest destruction. In Cebu, where forests have been almost totally lost, underground water coming out of private wells have become brackish. Siltation problems occur in major rivers and dams because of the destruction of watersheds. The glaring example is the Agno River, some areas of which overflow to surrounding fields due to heavy siltation. Deforestation also reduces rainfall, as was found in a study in Northern Luzon in the mid-seventies (Tujan, 1997). Much of our floods are traceable to forest denudation. Examples are flooding catastrophes in Cagayan Valley where entire villages were washed away in Mindanao where flash floods occur every now and then, in very denuded Negros which experienced destructive floods which brought down huge logs from the mountains and eroded thousands of hectares of productive farm land. In 1991, the tragedy in Ormoc City, which has only 10 percent forest cover left, claimed 8,000 lives and millions worth of properties (Tujan, 1997; Vitug, 1993). Forest destruction has also threatened the country’s genetic resources, putting many species on the endangered list, and bringing some on the verge of extinction (Table 7). Out of 1,657 existing wildlife species in the country, 47 country could be extinct by now, are endangered (including the tamaraw, crocodile and the famous monkey eating eagle). Seven ornamental plants are endangered and the gigantic molave trees, “the best that can be found in the universe”, are practically extinct. Aside from List 1, as of 1996, there have been 10 identified rare, endemic, and endangered plants of the Philippines (Tujan, 1997; EMB, DENR, 1996). 174 Table 7: Partial list of priority species Common Name Fauna A. Wild Birds Spot-billed Pelican/Philippine Pelican Serpent Eagle Philippine Eagle/Monkey Eating Eagle Philippine Hawk Eagle Philippine Megapode/Incubator Bird Palawan Peacock Pheasant Negros Fruit Dove Luzon Bleeding Heart Pigeon Nicobar Pigeon Mt. Apo Lorikeet/Mindanao Lorikeet Philippine Cockatoo/Red-vented Cockatoo Philippine Hanging Parakeet Oriental Hawk Owl/Philippine Horned Owl Mindanao Parrotfinch Peregrine Falcon Spotted Green Shank Mindoro Imperial Pigeon Koch’s Pitta Giant Scops Owl Parrots (all species) Falcons Pygmy Curlew Rufous Hornbill B. Mammals Tamaraw Calamian Deer Mouse Deer/Luzon Sambar Deer Status Threatened CITES II Endangered - CITES II CITES II CITES II Vulnerable - CITES II Threatened Threatened - CITES II CITES II CITES II Insufficiently known CITES II CITES II CITES II Threatened CITES I CITES I CITES I CITES I CITES I CITES II CITES II CITES II CITES II CITES II Vulnerable - CITES II Vulnerable CITES III CITES III Palawan Bear-Cat Indeterminate Luzon Forest Rat CITES II Philippine Monkey/Long-Tailed Macaque Endangered Philippine Tarsier Philippine Tree Shrew/Mindanao Slender- CITES II CITES II tailed Shrew CITES II Palawan Scaly Anteater Dugong Pangolin CITES II Rare - CITES II C. Reptilla Indeterminate Philippine or Freshwater crocodile CITES I Gray Monitor Lizard CITES I Leyte Freshwater Turtle CITES I Hawksbill Turtle Olive-backed/Pacific Ridley’s Logger CITES I CITES II Head 175 Table 5. Con’t… Green Sea Turtle Saltwater or Estuarine Crocodile Phyton CITES CITES CITES CITES CITES CITES CITES CITES CITES CITES CITES CITES Flora Sander’s Alocasia Striped Alocasia Pither Plant Orchids Bungang Ipot Voyavoi Calakab/Dalubi Tagbak Cycas/Pitogo Ferns Aloe/Sabila Cactus I I I II II II II II II II II II CITES I – Trade of species and subspecies of wildlife is strictly prohibited except for education, scientific or research and study purposes. CITE II – Populations of species and subspecies of wildlife highly need local protection set under national policies as determined by the country’s CITES Management Authority CITES – Convention Trade of Endangered Flora and Fauna Source: Protected Bureau, 1996 on International Species of Wild Areas and Wildlife Lastly, the destruction of our forests spells the displacement and dislocation of the indigenous peoples and upland dwellers whose virtual environments are the forests. Causes of Deforestation in the Philippines According to the survey of the Department of Environment and Natural Resources, the activities of the 176 common man or woman, most probably the indigenous peoples and upland dwellers are the principal causes of deforestation (Table 8). Table 8. DEFORESTATION BY REGION, 1995 (in hectares) REGION CAUSES Kaingin Illegal Logging CAR 1 2 3 4 5 6 7 8 9 10 11 12 ARMM 355.00 24.73 0.00 0.80 3.31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7.86 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1,479.07 1,678.96 4,296.65 1,808.94 14.15 0.00 183.54 432.80 43.00 204.00 153.54 36.07 0.00 0.00 0.00 720.40 0.00 12.00 2,238.40 10,993.00 0.00 70.55 0.00 0.00 40.00 0.00 0.00 0.00 1,841.93 2,424.09 4,321.76 1,820.94 2,254.35 10,996.31 183.54 503.35 43.00 204.00 193.54 36.07 0.00 0.00 PHILS 408.95 8.86 10,330.72 14,074.35 24,822.88 Source: Forest Fire Others Total Department of Environment and Natural Resources Table 8 gives several misconceptions about the major causes of deforestation. One, forest fires rank as the most destructive cause which, according to the DENR, worsened “during the El Niño phenomenon which recurs every ten years.” Two, mining operations which are man-made are lumped together with volcanic eruptions which are natural calamities as “other” causes. Three, kaingin is destructive while the DENR recognizes that upland settlers and peasants are “very knowledgeable on the concepts of stewardship and possess a vast knowledge of local environment conservation measures.” Therefore, kaingineros, marginalized, dislodged and escaping from a pattern of land ownership, are victims of a more systematic cause of deforestation. Lastly, the DENR recognizes that there is no clear line drawn between legal and illegal logging. Precisely so, because of the 177 much abused license held by big loggers who do not possess concepts of reforestation and responsibility. The small loggers, now deemed as illegal, are just victims of a large-scale exploitation (Tujan, 1997; EMB, DENR, 1996). Loss of Tropical Forests Tropical forests, which cover about 6 percent of the earth’s land area, grow near the equator in Latin America, Africa, and Asia. About 56 percent of the worlds tropical forests have already been cleared or damaged. Satellite scans and ground-level surveys indicate that the remaining forests are vanishing rapidly, at a rate of at least 154,000 square kilometers (59,000 square miles) per year equivalent to about 34 city blocks per minute, or almost two football fields per second. Its estimated that an equivalent area of these forests is damaged every year (Miller, 1994). Reforestation in the tropics scarcely deserves the name, with only one tree planted for every 10 trees cut. In Africa, the rate is 1 to 29. If the current rate of loss continues, all remaining tropical forests (except for a few preserved but still vulnerable patches) will be gone within 30 to 50 years, and much sooner in some areas (Miller, 1994). Why should we care about Tropical Forests Environmentalists consider the plight of tropical forests to be one of the world’s most serious environmental problems. These forests are home to at least 50 percent (some estimate 90 percent) of the earth’s total stock of species, most of which are still unknown and unnamed (Miller, 1994). Tropical forests touch the daily lives of everyone on Earth through the products and ecological services they provide. These forests supply half of the world’s annual harvest of hardwood, hundreds of food products (including coffee, tea, cocoa, spices, nuts, chocolate, and tropical fruits) This include many materials (including natural latex rubber, resins, dyes, and essential oils) than can be harvested sustainably and generate twice as much revenue 178 per hectare as timber production and three times as much as cattle ranching (Miller, 1994). The active ingredients for 25 percent of the world’s prescription drugs are substances derived from plants, most of which grow in tropical rain forests. Such drugs are used in birth control pills, tranquilizers, muscle relaxes, and life-saving drugs for treating malaria, leukemia and Hodgkin’s disease, testicular and lung cancer, heart disease, high blood pressure, multiple sclerosis, venereal warts, and many other diseases. Seventy percent of the 3,000 plants identified by the National Cancer Institute as sources of cancer-fighting chemicals come from tropical forests. While you are reading this page, a plant species that could cure a type of cancer, AIDS, or some other deadly disease might be wiped out forever (Miller, 1994). Botanists also believe that tens of thousands of strains of plants with potential food value await discovery in tropical forests. Despite their immense potential, less than one percent of the estimated flowering plant species in the world’s tropical forests have been examined closely for their possible use as human resources (Miller, 1994). Biologist E.O. Wilson warns that destroying these forest and the species they support for short-term economic gain is like throwing away a wrapped present or burning down an ancient library before you read the books. In addition, the Environmental Policy Institute estimates that unless destruction of tropical forests stops, the resulting flooding and loss of topsoil could cause as many as a billion people to starve during the next 30 years (Miller, 1994). C. Global Causes of Tropical Deforestation The two major underlying causes of the current massive destruction and degradation of tropical forest are (Miller, 1994): Population growth and poverty, which combine to drive subsistence farmers and the landless poor to tropical forests to try to grow enough food to survive, often using unsustainable methods. 179 Massive foreign debt and policies of governments and international development and lending agencies that encourage rapid depletion of resources to stimulate short-term economic growth. Less developed countries (LDCs) are encouraged to borrow huge sums of money from more developed countries (MDCs) to finance economic growth. To pay interest on their debts, these countries often sell their forest, mineral, oil, and other resources - mostly to MDCs - at low prices dictated by the international marketplace. The process of degrading a tropical forest begins with a road. Once the forest becomes accessible, it is usually cut or degraded and fragmented into vulnerable patches by the following activities: Unsustainable small-scale farming. Colonist follow logging roads into the forest to plant crops on small cleared plots, to build homes, and to try to survive. With little experience in potentially sustainable slashand-burn and shifting cultivation, many newcomers cut and burn much forest to grow crops and don’t allow depleted soils to recover, ultimately degrading large tracts of forest. Cattle ranching. Cattle ranches are often established on exhausted and abandoned cropland, often aided by government subsidies to make ranching profitable. Overgrazing further degrades the land. Commercial logging. Since 1950, the consumption of tropical lumber has risen 14-fold, with Japan now accounting for 60 percent of annual exports (followed by the United States and Great Britain). The World Bank estimates that by 2000, only 10 of the 33 countries now exporting tropical timber will have any left to export. Although timber exports to MDCs contribute to tropical forest depletion and degradation, over 80 percent of the trees cut in LDCs are used at home Raising cash crops. Tropical forests are cut and converted to immense plantations used to grow crops such as sugarcane, banana, tea, and coffee, mostly for export to MDCs. 180 Mining operations. Most of the extracted minerals, such as iron ore and bauxite (aluminum ore) are exported to MDCs. Oil drilling and extraction. Damming rivers and flooding large areas of forest. D. Solution: Reducing Tropical Deforestation Environmentalists have suggested the following ways to reduce tropical deforestation (Miller, 1994): Use remote-sensing satellites to find out how much of the world is covered with forest and how much has been deforested. This could be done for about what the world spends for military purposes every three minutes. Establish a mandatory international system for identifying tropical (and other) timber grown and harvested sustainably. So far, only 0.1 percent of the world’s tropical forests are managed sustainably. Reform tropical timber-cutting regulations and practices. New logging contracts would charge more for timbercutting concessions and require companies to post adequate bonds for restoration and reforestation. Fully fund the Rapid Assessment Program (RAP), which sends biologists to assess the biodiversity of “hot spot” - forests and other habitats that are both rich in unique species and in imminent danger - with the goal of channeling funds and efforts toward immediate protection of these endangered ecosystems. Use debt-for-nature swaps and conservation easements to encourage countries to protect tropical forests or other valuable natural systems. In a debt-for-nature swap, participating tropical countries act as custodians for protected forest reserves in return for foreign aid or debt relief. With conservation easements, a country, a private organization, or a group of countries compensates individual countries for protecting selected forest areas. 181 Help settlers learn how sustainable agriculture. Stop funding tree and crop plantations, ranches, roads, and destructive types of tourism on any land now covered by old-growth tropical forests. Concentrate farming tree and crop plantations, and ranching on cleared or degraded tropical forest areas that are in various stages of secondary ecological succession. Set aside large protected areas for indigenous tribal peoples. Indigenous peoples are the primary guardians and sustainable users of vast, mostly undisturbed habitats. These peoples are being driven from their homelands in tropical forests and other biomes by commercial resource extractors and the landless poor. Pressure banks and international lending agencies (controlled by MDCs) not to lend money for environmentally destructive projects especially road building involving old-growth tropical forests. Reduce poverty and the flow of the landless tropical forests by slowing population growth. Reforest and rehabilitate degraded tropical forests and watersheds. Work with local people to protect forest. to practice small-scale poor to II. Biodiversity Biodiversity is the totality of genes, species, and ecosystems in a region. The wealth of life on earth today is the product of hundreds of millions of years of evolutionary history. Over the course of time, human cultures have emerged and adapted to the local environment, discovering, using, and altering local biotic resources. Many areas that now seem “natural” bear the marks of millennia of human habitation, crop cultivation, and resource harvesting. The domestication and breeding of local varieties of crops and livestock have further shaped biodiversity (Reid et. al., 1992). 182 Biodiversity categories-genes, quite different scientists measure can be divided into three hierarchical species, and ecosystems that describe aspects of living systems and that in different ways. Genetic diversity refers to the variation of genes within species. This covers distinct populations of the same species (such as the thousands of traditional rice varieties in India) or genetic variation within a population (which is very high among Indian rhinos, for example, and very low among cheetahs). Until recently, measurements of genetic diversity were applied mainly to domesticated species and populations held in zoos or botanic gardens. Increasingly the techniques are being applied to wild species (Reid et. al., 1992). Species diversity refers to the variety of species within a region. Such diversity can be measured in many ways, and scientists have not settled on a single best method. The number of species in a region-its species “riches” is one often-used measure, but a more precise measurement, “taxonomic diversity,” also considers the relationship of species to each other. For example, an island with two species of birds and one species of lizard has greater taxonomic diversity than an island with three species of birds but no lizards. Thus, even though there may be more species of beetles on earth than all other species combined, they do not account for the greater part of species diversity because they are so closely related. Similarly, many more species live on land than in the sea, but terrestrial species are more closely related to each other than ocean species are, so diversity is higher in marine ecosystems than a strict count of species would suggest (Reid et. al., 1992). Ecosystem diversity is harder to measure than species or genetic diversity because the “boundaries” of communities - associations of species and ecosystems are elusive. Nevertheless, as long as a consistent set of criteria is used to define communities and ecosystems their number and distribution can be measured. Until now, such schemes have been applied mainly at national and subnational levels, though some coarse global classification have been made (Reid et. al., 1992). 183 Besides ecosystem diversity, many other expressions of biodiversity can be important. These include the relative abundance of species, the age structure of populations, the pattern of communities in a region, changes in community composition and structure over time, and even such ecological processes as perdition, parasitism, and mutualism. More generally, to meet specific management or policy goals, it is often important to examine not only compositional diversity but also genes, species, and ecosystems (Reid et. al., 1992). Importance of Biodiversity The conservation of biodiversity is important in both economic and ethical terms. There is no shortage of example of wild animals and plants being put to service for the benefit and economic development of mankind: new drugs, new fibers, new foods, new genetic capabilities. All these things are derived from often unexpected sources in nature, sources that have survived more by chance than by human design or management. Beyond this, however, lies a nonmaterial valuation of biodiversity, less often expounded and still less often grasped, but in many ways more powerful (FPE & PBC, 1994). While in the economic sense, biodiversty represents unimaginable wealth. In the ethical sense it is simply priceless. The Ethical Importance Ethics provide the basis for deciding what is good or bad or right or wrong. The importance of ethics in helping to make good choices concerning nature is well recognized. The world Charter for Nature, adopted by the United Nations General Assembly in 1982, states: “Every form of life is unique, warranting respect regardless of its worth to man, and to accord other organisms such recognition, man must be guided by a moral code of action” (FPE & PBC, 1994). Importance of Biodiversity to Food (FPE & PBC, 1994) Only seven species provide 75 percent of human nutrition, namely: wheat, rice, maize, potato, barley, sweet potato 184 and cassava. The first three provide more than 50 percent of human nutrition. Roughly 20 percent of protein requirements of humans in developing countries is provided by animals. Fifty five percent of protein requirements of humans in developed countries is provided by animals. Only 5,000 out of 75,000 edible plant species on earth have been used for food by humans. Humans depend on only three plant species for 60 percent of their calorie requirement and 56 percent of their protein requirement. Temperate zone plants provide about 10 fruit species while the tropical rainforests supply almost 200 and over 3,000 species are available. Importance of Biodiversity to Health (FPE & PBC, 1994) Less than 1 percent of tropical plants has been screened for medical uses. Only 5,000 species of higher plants have been studied as potential medicinal sources. Some 119 pure chemical substances are extracted from higher plants which are used in medicines worldwide. These are obtained from less than 90 species of plants. Forty percent of all prescription drugs used in industrialized countries are derived from plant and animal species. Amazonian Indians use 1,300 plant species as medicines. Traditional healers in Southeast Asia use 6,500 plant species as medicines. At least 68 common plants in the Philippines are being used as medicines. A total of 3,000 plants are found in tropical rainforests, 70 percent of which have been identified by the US National Cancer Institute as having anti - cancer properties. One out of 10 plant species is believed by scientists to contain compounds with ingredients that are active against cancer. All prescription and non-prescription drugs containing active ingredients derived from plants are worth $40 billion each year. 185 Tubocurarine, a muscle relaxant used in surgery is derived from plant - based curare, a substance used by South American Indians to poison-tip blowpipe darts. China has over 5,000 medicinal plants, 1,700 of which are used commonly. Some of the most toxic natural substances known come from marine organisms. More than 500 marine organisms yield chemicals with anticancer potential, e.g., serum from horseshoe crabs serves to isolate tumor cells from the blood of cancer patients, and it is also a source of substances used to detect bacterial toxins in human blood; shark livers contain lipids that enhance human resistance to cancer; and clams yield extracts which delay cancer development in mice. Some animals which possess medicinal values include: blister beetles provide contharidin used to treat urinogenital disorders; leeches produce hirudin, a valuable anti-coagulant; bee venom is used in the treatment of arthritis; and venom from a Brazilian snake is used to produce captopril which helps control hypertension. Plants are extraordinary chemical factories and some of their chemicals have revolutionized certain procedures, e.g., steroid from a Mexican yam enable “the Pill” to be developed as a mass birth-control agent; the rosy periwinkle, a pretty little plant from Madagascar, yielded vincristine and vinblastine which, when used with other treatments, increased the long-term complete remission chances of children stricken with leukemia from 20 percent to 80 percent. Some other plant compounds have served as natural chemistry lessons, the essential items ultimately being manufactured synthetically. The aspirin story is a classic example. Dioscorides described as the white willow (Salix alba) is a pain killer in Materia Medica. The active ingredient was identified in the 19th century and named salicin. A similar compound was also isolated from meadowsweet (Spirea ulmaria) and named salicylic acid. In 1899, it was found that a mixture of this with acetic acid was more effective, and the new compound (acetylsalicylic acid) was named aspirin (after Spirea). It is now manufactured synthetically, and is the most widely-taken medicine in the world. Quinine, an alkaloid from the bark of the Cinchona tree, was first isolated in 1820. It was successful in the 186 treatment of malaria. A demand for the drug almost wiped out the producer trees until mass production was made possible through a high yielding strain which lent itself to cultivation. Importance of Biodiversity to Industry (FPE & PBC, 1994) Due to rapid depletion, Philippine forests now contribute only 1.7 percent to the gross national product. Forty million tons of bananas are consumed by humans each year. Humans consume 1.3 million tons of mangoes and 1.5 million tons of papayas each year. “Minor forest products”, such as rattan, bamboo, fruits, nuts, and spices are worth $10 billion each year. At least 2,100 plants are reported to have pestcontrolling property powerful enough to be commercially developed. Natural starches are used in fabrics, glue, soaps, cosmetics, medicines, numerous prepared foods, photographic film, explosives, colourings, car tires, plastics, several industrial processes and even the preservation of human blood plasma. Rubber ranks among the world’s top crops. Timber is the biggest wild plant contributor to industry with a world trade value of US$ 40 billion per year. The world currently consumes 10,000 years worth of solar energy in one year’s supply of coal alone. Over time, the greatest value of the variety of life may be found in the opportunities it provides humanity for adapting to local and global change. The unknown potential of genes, species, and ecosystems represents a never-ending biological frontier of inestimable but certainly high value. Genetic diversity will enable breeders to tailor crops to new climatic conditions. Earth’s biota - a biochemical laboratory unmatched for size and innovation hold the still-secret cures for emerging diseases. A diverse array of genes, species, and ecosystems is a resource that can be tapped as human needs and demands change (Reid et. al., 1992). Because biodiversity is so closely intertwined with human needs, its conservation should rightfully be 187 considered an element of national security. It has become increasingly apparent that national security means much more than military might. Ecological dimensions of national security cannot be ignored when countries fight over access to water or when environmental repugees strain national budgets and public infrastructure. A secure nation means not only a strong nation, but also one with a healthy and educated populace, and a healthy and productive environment as well. National security will be strongest in countries that care for their biodiversity and the services it provides. The many values of biodiversity and its importance for development suggest why biodiversity conservation differs from traditional nature conservation. Biodiversity conservation entails a shift from a defensive posture protecting nature from the impacts of development - to an offensive effort seeking to meet peoples needs from biological resources while ensuring the long-term sustainability of Earth’s biotic wealth. It thus involves not only the protection of species but also the safeguarding of the genetic diversity of cultivated and domesticated species and their wild relatives. This goal speaks to modified and intensively managed ecosystems as well as natural ones, and it is pursued in the human interest and for human benefit. In sum, biodiversity conservation seeks to maintain the human life support system provided by nature, and the living resources essential for development (Reid et. al., 1992). Losses of Biodiversity and their Causes We aren’t quite sure who is cutting our forests and who is going to flood our land but we know they live in town, where rich people are getting richer, and we poor people are losing what little we have (Statement of the Iban People, Sarawak, Malaysia). Biological diversity is being eroded as fast today as at any time since the dinosaurs died out some 65 million years ago. The crucible of extinction is believed to be in tropical forests. Around 10 million species live on earth, according to the best estimates and tropical forests house between 50 and 90 percent of this total. about 17 million hectares of tropical forests - an area four times the size of Switzerland - are now being cleared annually and 188 scientists estimate that at these rates roughly 5 to 10 percent of tropical forest species may face extinction within the next 30 years. This estimate may prove conservative, however. Rates of tropical forest loss are accelerating, and some particularly species-rich forests are likely to be largely destroyed in out lifetime. Some scientists believe that about 60,000 of the world’s 240,000 plant species, and perhaps even higher proportion of vertebrate and insect species, could lose their lease on life over the next three decades unless deforestation is slowed immediately (Reid et. al., 1992). Tropical forests are by no means the only sites with endangered biodiversity. Worldwide, nearly as much temperate rain forest - once covering an area nearly the size of Malaysia - has also been lost. Although the total extent of forest in the northern temperate and boreal regions has not changed much in recent years, in many areas the species rich, old-growth forest have been steadily replaced by second-growth forests and plantations. Evidence of accelerating clearance of temperate forests is also appearing: between 1977 and 1987, 1.6 million hectares of forest was lost in the United States alone (Reid, et. al., 1992). In several spots in Europe, fungal species diversity has dropped by 50 percent or more over the past 60 years. In such “Mediterranean” climes as California, South Africa, central Chile, and Southwest Australia, at least 10 percent of all plant and animal species are imperiled. The largest number of recent extinctions have been on oceanic islands: some 60 percent of plant species endemic to the Galapagos Islands are endangered, as are 42 percent of the Azores endemic species and 75 percent of the endemic plant species of the Canary Islands Reid et. al., 1992). The biodiversity of marine and freshwater systems faces serious loss and degradation. Perhaps hardest hit of all are freshwater ecosystems, battling long term pollution and the introduction of many alien species. Marine ecosystems too are suffering from the loss of unique populations of many species and are undergoing major ecological changes (Reid et. al., 1992). The number of documented species extinctions over the past century is small compared to those predicted for the coming decades. This difference is due, in part, to the 189 acceleration of rates of habitat loss over decades but also to the difficulty of documenting extinctions. The vast majority of species has not yet even been described, and many may disappear before they are even known to science (Reid, et. al., 1992). Habitat loss not only precipitates species extinctions, it also represents a loss of biodiversity in its own right. In many countries, relatively little natural vegetation remains untouched by human hands. In Bangladesh, only 6 percent of the original vegetation remains. Forests around the Mediterranean Sea probably once covered 10 times their current area, and in the Netherlands and Britain, less than 4 percent of lowland raised bogs remain undamaged (Reid et. al., 1992). The dramatic losses of species and ecosystems obscure equally large and important threats to genetic diversity. Worldwide, some 492 genetically distinct populations of tree species (including some full species) are endangered. In the northwestern United States, 159 genetically distinct populations of ocean-migrating fish are at high or moderate risk of extinction, if they have not already slipped into oblivion (Reid et. al., 1992). Loss of genetic diversity could imperil agriculture. How much the genetic base has already eroded is hard to say, but since the 1950s, the spread of modern “Green Revolution” varieties of corn, wheat, rice, and other crops has rapidly squeezed out native landraces. Modern varieties were adopted on 40 percent of Asia’s rice farms within 15 years of their release, and in the Philippines, Indonesia, and some other countries, more than 80 percent of all farmers now plant the new varieties. In Indonesia, 1500 local rice varieties have become extinct in the last 15 years. A recent survey of sites in Kenya with wild coffee relatives found that the coffee plants in two of the sites had disappeared, three sites were highly threatened, and six were possibly threatened. Only two were secure (Reid et. al., 1992).