The study of our geography, natural resources and environment is of vital importance to all Puerto Ricans. The island’s ecosystems and the normal interaction between its components and species have been subjected to the pressures of years of economic development. Despite current legislation, the effects of an increasing population and urban development have left their impact on our environment. Many of the island’s bodies of water suffer the results of sedimentation, pollution and landfill. Deforestation, loss of soils, urban sprawl, and overfishing have threatened 29 animal and 49 plant species in Puerto Rico, which are currently listed on U.S. federal endangered species lists, and also led to the extinction of 16 or 17 species of mammals, all of which are an indication of the tremendous impact humans have on the island`s natural environment.

Puerto Rico’s ecological formations are influenced by the interrelation between the geological events of the past, the island’s physiography, as well as climatic factors such as precipitation, temperature, and wind. These factors define geographic structure and also determine the composition of species within a given ecosystem. Social interrelations and anthropogenic factors have combined with physical, chemical, and biological factors to influence and modify the island’s environment.


Puerto Rico is a largely mountainous archipelago, with a surface area on the main island of 161 km (100 miles) in length by 56 km (35 miles) in width. Puerto Rico’s oceanic development began some 200 to 110 million years ago. The island has three main geomorphic regions: the mountainous interior, the coastal plains, and the karst region. The mountainous region dominates the island`s interior, running from east to west. This region includes the Central Mountain Range, the Cayey mountains, the Luquillo mountains and the Bermeja mountains. Igneous volcanic as well as intrusiveactivity led to the formation of most of the materials comprising the island’s interior mountain chain.

The coastal plains extend from the northern shoreline some 13 to 20 km (8 to 12 miles) toward the interior, in the south 3 to 13 km (2 to 8 miles), and in some isolated valleys along the island’s east and west coasts. These alluvial valleys are geologically the most recent of the island’s regions, having been formed less than two million years. Coastal plains are the result of the processes of varying sea levels as well as erosion over the millennia. Like the island’s interior, the coastal region offers a great abundance and variety of panoramas as well as extremely valuable natural resources.

The karst region, which is composed of limestone produced by calcium carbonate deposits from marine organisms, features a unique landscape of steep promontories (haystack hills), turrets, sinkholes and caves. These formations emerged as a result of fluctuations in sea level as well as the rising of the earth due to various geological processes. The island`s karst regions range in geological age from 6 to 45 million years. These regions account for nearly 40 percent of the island`s total land mass, extending mostly along the island’s northern coastal plain from Loíza to Aguada. In the south, they include discontinuous areas running from Juana Díaz to Cabo Rojo. There are also some isolated limestone formations in Aguas Buenas, Cayey, and a few other locations, as well as on the islands of Mona and Monito.

The islands comprising Puerto Rico are located in the tropics and are bounded on the north by the Atlantic Ocean and on the south by the Caribbean Sea. The archipelago is situated along the route of the trade winds, which blow from the northeast. These winds bring a considerable amount of moisture, particularly from June through November. The moisture from these winds is transformed into rain upon impact with the northern flank of the island’s Luquillo mountain range. The opposite effect occurs in the southern area, since in the process of crossing the mountains these winds become dry, and therefore produce little rain. Thus, the northeastern corridor contains one of the most humid ecosystems in the Caribbean National Forest, which receives an average of about 160 inches (more than 4,000 mm) of rain each year, while the southwest is home to the island’s driest forest area, the Guánica Dry Forest. Here rainfall totals only 35 inches (890 mm) annually, or less. Both forests have been specially designated as world`s biosphere reserves by the United Nations.

Although data varies slightly from one source to another, Puerto Rico as a whole receives an average of 72 inches (1,828 mm) of rainfall annually. Of this amount, the island loses 46 inches (1,780 mm) through the process of evapotranspiration, and 23 inches (584 mm) through surface runoff, while 1 inch (25 mm) is stored among the island’s bodies of water, 1 inch (25 mm) enters the various groundwater systems, and another 1 inch (25 mm) is used for human consumption.

Puerto Rico’s bodies of water can be divided into two types: lotic and lentic. Lotic pertains to running bodies of water, such as rivers, streams and springs, which are characterized by rapid flow and significant movement of sediments. Puerto Rico has about 100 rivers that source in the Central Mountain Range and run precipitously until they reach the coastal plains. The island`s rivers and streams follow four different courses: toward the north, or Atlantic; toward the south, or Caribbean; toward the east, Vieques Sound; and toward the west, Mona Passage. North-flowing rivers tend to be significantly wider, longer and more voluminous in comparison to the island’s other river systems.

In contrast, lentic bodies of water are characterized by slow-moving waters, such as lakes, lagoons, ponds and marshes. Almost all of the important marsh and swamp areas on the island are associated with the flood plains abutting the island`s major rivers. Lagoons and marshes account for significant portions of Puerto Rico’s coastal plains in the east, north and west of the island. While these ecosystems were formerly dominated by trees, they are now characterized mainly by shrubs and grasses which are adapted to damp conditions.

The largest groundwater reservoir is located in the northern karst region. Unconfined and confined aquifers in the region are capable of supplying up to 174 million gallons of water a day. These water sources feed eight of the islands rivers, as well as such marsh reserves as Laguna Tortuguero and Caño Tiburones, among others.

Rocky coast of Cabo Rojo, a municipality in the western region of Puerto Rico

Rocky coast of Cabo Rojo, a municipality in the western region of Puerto Rico

While there are various ways to describe Puerto Rico’s ecological life zones, one of the most accepted models has been proposed by L. R. Holdridge, which is essentially based on climatic influences, despite some discrepancies largely relating to the existence of subtropical vegetation on a primarily tropical island. Classification is adjusted according to average rainfall, evapotranspiration and biotemperature. According to this system, there are six life zones in Puerto Rico and US Virgin Islands: subtropical moist forest (58.4%), subtropical wet forest (22.6%), and subtropical dry forest (17.6%), which account for most of the island. To a lesser degree, the island is characterized by subtropical lower montane wet forest (1.2%), subtropical wet forest (0.1%), and subtropical lower montane rain forest (0.1%). All of Puerto Rico’s forests are characterized by vegetation whose environmental conditions are specifically associated with a tropical climate.

Puerto Rico’s coast is marked by various ecological formations, such as cliffs, dunes, beaches, hillocks, sinkholes, forests, freshwater and saltwater lagoons, mangrove swamps, salt marshes, flood plains, bays, islets and keys, which, taken as a whole, provide the island with its own distinctive identity.

Coastal ecosystems are determined by zone, i.e., ecosystem distribution follows the characteristics of a given coastal area. Extending from the coastline, we first find the mangrove swamp, followed by areas of marine vegetation, such as seagrass, and finally the coral reef. These natural systems are influenced by the extent and sloping of the insular platform. The island’s east, northeast, south and southwest coasts have more extended platforms, which allow for the proliferation of mangroves. In the north, mangroves grow alongside rivers and saltwater lagoons, providing a natural form of protection. Along the southern coast, mangroves are found abutting the shoreline due to the area’s softer wave patterns.

Mangroves are characterized as swampland. Swamps are low-lying areas of terrain with fine, loose sediment that retains large amounts of water. Swamps are either completely or partially flooded on a permanent, periodic, or seasonal basis. The vegetation growing in such areas has adapted to live under water. Other examples of swampland include marshes, Pterocarpus forest, and seagrass beds.

Both humans and the environment benefit directly and indirectly from the mangroves, which provide a source of organic and inorganic materials for sustaining the food web of adjacent bodies of water. Mangroves produce large quantities of oxygen and serve as a habitat for 70 species of endemic, native and migratory birds. They also provide a breeding ground for many marine species during their early stages of development. Mangroves are highly efficient at reclaiming terrain since they function as stabilizers for shore areas affected by erosion. They also form a buffer from the sea when natural phenomena, such as storm surges, occur. Four species of mangrove are found in Puerto Rico: red, white, black and buttonwood mangrove.

Bioluminescent bays are associated with mangrove ecosystems. These areas are habitat to microscopic luminescent organisms (dinoflagellates), which are concentrated in lagoons or bays bordered by mangroves. The bay must be semi-enclosed, thereby affording a greater concentration of the organisms, and conditions of total darkness are required in order to perceive the dim light emitted by the dinoflagellates. Puerto Rico’s most renowned bioluminescent bay is located in La Parguera, on Puerto Rico’s southwest coast. However, other bays that are equally important from an ecological standpoint are also found at Laguna Grande in Fajardo, Piñones and Torrecillas lagoons in Carolina, Joyuda lagoon in Cabo Rojo, Mar Negro in Salinas, and Mosquito Bay on the island of Vieques. These systems are characterized by similar nutrient levels, low turbidity, depth, and quantity of organic matter.

Another coastal ecosystem is the beach, whose main materials are in the form of loose particles which are constantly in the process of movement. These particles originate from soil erosion, whereby sediments are transported to the coast via river or stream systems, or from marine organisms, such as calcareous algae, coral, shells, fish scales, and sea urchin and starfish fragments brought in by waves. Beaches provide a habitat for organisms that live below the tideline (sublittoral) as well as above it (supralittoral), all of which are adapted to survive prevailing conditions. Some bury themselves or have shells to resist the abrasive action of the sand, or to protect them from desiccation or corrosion by salt. Beach dunes provide a home for various plant species, which also serve to stabilize the sand, such as low-lying vines and shrubbery.

In contrast, Puerto Rico’s rocky coastline is largely the result of eolianite or cemented dune formations. Such formations are common along the island’s north coast. Submerged rocky areas provide a shelter for organisms such as sea cucumbers, anemones, sea urchins, and other filtering organisms. More exposed areas, such as intermediate rockface concavities or depressions, also serve as a habitat for a variety of organisms. These small pockets are subject to immersion, and the water found here tends to be warmer and more saline. Sea urchins, which consume algae, thrive in such areas, along with small fish, snails and shellfish, and algae. The upper rockface, which only receives the effect of sea spray, is home to snails, which can resist high temperatures and desiccation.

Beds of seagrass can be found along all of Puerto Rico’s coasts. Seagrasses grow in shallow submerged shore areas. These zones provide a home for many organisms, such as sea cucumbers, starfish, sea urchins, fishes such as barracuda, blue stripe grunt, porgy and groupers, as well as mollusks such as conch. Creatures that consume these grasses include the manatee and the green sea turtle.

The coral reef is the most developed and diverse of the marine ecosystems due to the innumerable niches it provides for a vast array of species. Coral reefs develop from hard substrate in transparent and moderately shallow waters, which provide access to sunlight and which are in proximity to the action of waves. Puerto Rico’s most extensive coral reefs are located along the island’s southern coast, where there are few rivers to channel fresh water and sediment, that can be harmful to reefs. The healthiest and most exuberent reefs are found around the islands of Mona, Caja de Muertos, Culebra, Desecheo, as well as Tourmaline Reef west of Mayagüez, which is one of the most distant reefs from the main island’s coastline.

Coral, which is the reef’s basic building block, is composed of tiny polyps with tentacles. The tentacles are visible at night when the coral is feeding on zooplankton. Coral polyps live in symbiosis with microscopic algae called zooxanthella, which provides the coral with oxygen. In return, the coral provides nutrients to the algae. Coral reefs represent the most biodiverse marine community because they provide food and shelter to a tremendous number of species such as algae, sponges, anemones, sea urchins, starfish, lobster, crab, octopus, as well as other mollusks, fish and plants. Reefs provide a habitat for approximately 650 fish species, which form a relationship with this ecosystem during at least some stage of their lives.

El Yunque National Forest

El Yunque National Forest

Puerto Rico has a number of areas of great ecological value designated as forests, natural reserves, and refuges. These areas are managed by state or federal agencies and nonprofit foundations. Natural reserves are areas whose purpose is to protect ecosystems, communities, or biological or geological elements -which, due to their rarity, fragility, representative nature, importance, or singularity merit special consideration and treatment. These areas are designated through state programs or legislation such as the Coastal Zone Program and the Natural Patrimony Program Law. Other designations are also made directly by the legislature of Puerto Rico or the U.S. government.

Puerto Rico’s forestry system includes coastal forests (Aguirre, Boquerón, Ceiba, Guánica and Piñones), karst forests (Cambalache, Guajataca, Río Abajo and Vega) and mountain forests (Carite, Maricao, Guilarte, Susúa, Toro Negro and Luquillo). Those located within the mountains or karst hills are suitable for the development of wood harvesting. Forests within the karst zone are distinguished by the seasonal nature of plant life, the large number of endemic species, and the different structure of vegetation, all of which are the result of adaptation to soil and topography. Initiatives by various community, environmental, and school groups to conserve key forest areas have led to the designation of the San Patricio and Adjuntas Municipal Forests as protected areas. Protection has also been sought for the lands surrounding the Botanical Garden in Río Piedras so that this area can be designated as the Municipal Forest for the New Millennium.

The reserve and refuge system includes the Cueva del Indio, Caño Tiburones, Tortuguero Lagoon, Cibuco Marsh, San Juan Bay National Estuary, La Cordillera, Canal Luis Peña, Vieques Bioluminescent Bay, Seven Seas, Lagunas de Humacao, Guayama Reef, and Punta Petrona Nature Reserves, as well as the Jobos Bay, Caja de Muertos, Mona and Monito, Guánica, La Parguera, Tourmaline Reef, and Joyuda Lagoon National Reserves. The natural reserves at Punta Guaniquilla, Punta Yeguas, Bosque Pterocarpus de Dorado, Hacienda La Esperanza, and Cabezas de San Juan are managed by the Puerto Rico Conservation Trust. The wildlife refuges at Culebra, Laguna Cartagena, Cabo Rojo, Isla Desecheo and Vieques are managed by the U.S. Fish and Wildlife Service.

Palominito Islet, Fajardo

Palominito Islet, Fajardo

The islands of Culebra and Vieques, located east of Puerto Rico, are also affected by trade winds and share many of the natural characteristics of southern Puerto Rico, where precipitation tends to be minimal. Therefore, the land is arid and vegetation is categorized as dry forest. Culebra’s total land area is 7,700 acres. The island’s topography is irregular, fluctuating between rolling lowlands and modest elevations. The highest point is Monte Resaca, at 650 feet (198 meters). The Culebra Wildlife Refuge accounts for 1,480 acres and includes 23 islets and marine rock formations, in addition to four parcels located on Culebra island itself. Canal Luis Peña was recently designated a natural reserve. This area contains extensive coral reef communities that enjoy healthier conditions than most of the reef communities in Puerto Rico.

Vieques is characterized by low-lying hills, punctuated by valleys and plains. The island’s highest peak, Monte Pirata, is 1,000 feet (305 m), and is located in the island’s western region. Cerro Matías in eastern Vieques, is 420 feet (128 m). The island has several small basins without any drainage channels, although it is believed that streams might have existed at some point in the past. High temperatures result in evaporation of 90% of the island’s precipitation. The island’s two main aquifers are located at Valle de Resolución, in western Vieques, and Valle Esperanza in the south. One of the island’s most outstanding features is the Vieques Bioluminescent Bay Natural Reserve.

Other important islands and keys include Desecheo, to the west of Puerto Rico, Caja de Muertos, in the south, and the Cordillera keys in the east. The latter archipelago is made of the islands of Icacos, Palominos, Blanquilla, cayo Diablo, as well as other islets. La Cordillera keys are home to a wide variety of unique ecosystems and wildlife. Mona Island, located 50 miles off Puerto Rico’s west coast, is a natural reserve of great scenic beauty and ecological importance. This natural sanctuary comprises 13,638 acres. Mona’s climate is dry, and the island is classified as a semiarid or dry region. Dramatic cliffs rising 100 feet or higher encircle much of the island. The coasts are ringed by reefs containing a great variety of hard and soft corals, which form a natural barrier protecting the western and eastern areas of southern shores. Mona is home to a complex system of more than 19 caves, some extending for several kilometers, many of which contain Taino petroglyphs. Mona Island is a crucial habitat for various endemic species, including the great Mona iguana, which is protected by law due to their vulnerability.

Coral reefs along Puerto Rico's coasts

Coral reefs along Puerto Rico’s coasts

Puerto Rico is one of the great pioneers in Latin America in promoting environmental legislation and creating regulatory agencies to monitor and control environmental pollution and degradation and preserve natural resources. However, these initiatives have not guaranteed the absolute protection of the island’s environment.

Under the Spanish Crown, laws were decreed with the principal aim of exploiting such natural resources as water, mountain areas and forests. Land was set aside and organized for the establishment of cities and communities. After Puerto Rico was transferred to theUnited States, under the 1898 Treaty of Paris, legislation approved by the U.S. Congress was also geared toward the use and exploitation of natural resources for human benefit.

Planning, as a government instrument, became institutionalized with the creation of the Planning Board, under Law 213 of May 12, 1942. The Planning Board’s main purpose was to guide economic, social and physical development in a coordinated and appropriate way, thereby guaranteeing the general welfare of the island’s residents and the efficient use of land and natural resources. The board oversaw development of the island, using Operation Bootstrap as its model. This program emphasized the creation of employment, as well as incentives for the construction industry.

After World War II, the deleterious effects of industrialization on the environment began to spark interest and focus attention on various social problems and concerns. As a result, the 1952 Constitution of the Commonwealth of Puerto Rico included the establishment of a public environmental policy, which is contained in Article VI, Section 19.

“It shall be the public policy of the Commonwealth to conserve, develop and use its natural resources in the most effective manner possible for the general welfare of the community…”.

Puerto Rico’s industrial development from the 1960s through the 1990s was largely based on the introduction of pharmaceutical, petrochemical, chemical, and derivative industries which greatly increased the risk for toxic spillage and contamination on the island. In the last three decades of the 20th century, at least seven major contaminant discharge events have occurred in Puerto Rico, with the resulting hazards to the island’s natural resources—particularly water, air and soil quality—as well as worker and resident health.

Since the 1960s, when specific environmental pollution problems began to be pinpointed, the need for establishing controls became clear and an attempt was made to confront environmental issues from a more holistic standpoint. The decade brought campaigns to protect the health of workers and communities. An outcry against experiments with Agent Orange in El Yunque; mining operations at Adjuntas, Jayuya, Utuado and Lares; and the displacement of residents at Vacía Talega for construction of tourist complexes marked the beginning of a new environmental awareness in Puerto Rico.

In 1969, the U.S. Congress ratified the National Environmental Policy Act (NEPA). This law requires that any significant environmental actions or decisions must first undergo examination of the environmental impacts of the proposed action, any unavoidable adverse environmental effects, and alternatives available to the proposed action (this procedure falls under what is referred to as the Environmental Impact Statement or EIS). In 1970, the Environmental Protection Agency (EPA) was formed. Its mission is to establish and enforce protection standards, thus achieving the environmental goals set forth in the NEPA.

In Puerto Rico, Law No. 9 was ratified on June 18, 1970 in order to establish the public environmental policy for environmental conservation, and to create the Environmental Quality Board. These mechanisms require that all government organs and agencies assess the environmental impacts of their actions and decisions before they come into effect. Law No. 9 provided the island with a legal framework for implementing the public policy initially established under the commonwealth’s constitution. Similarly, all government agencies are required to harmonize their regulations, policies, plans and programs with the Public Environmental Policy. It should be noted that on September 22, 2004, Law No. 9 was repealed and then replaced by Law No. 416, without any changes to the established public environmental policy or to the environmental impact statements.

Law No. 23 of June 20, 1972 created Puerto Rico’s Department of Natural and Environmental Resources (DNER)—as this agency is now called—to protect, conserve and manage the country’s natural and environmental resources in order to guarantee their enjoyment for future generations. The DNER has jurisdiction over wildlife and the island’s 19 state forests, 28 nature reserves and wildlife refuges, (which include 14 lakes or reservoirs), 4 lagoons, as well as protected sections of Culebra and Vieques. The DNER also oversees resources pertaining to the public domain, such as water, fish, minerals, waterways, shorelines, riverbanks and all areas and materials relating to the island’s rivers, the maritime-terrestrial zone, territorial waters and submerged lands, in addition to natural resources and systems, such as caves, caverns, sinkholes, mangrove swamps, marshes, and other critical habitats that are essential for wildlife and endangered species.

In 1975, operations at the former Planning Board were halted and a new Regulation and Permits Administration (RPA) was created as a spin-off under Law No. 76 of June 24, 1975. This same law created a new Planning Board, which operates under the Office of the Governor. The board’s mission has now been specified to develop a society based on a sustainable economy that will conserve and protect the environment for future generations to enjoy. The agency is responsible for balancing the needs of Puerto Rico’s natural, economic and social resources, as well as drawing up a Master Plan for the island’s development.

The Solid Waste Authority (SWA), which was created by Law No. 70 of June 23, 1978, is in charge of evaluating, planning and implementing strategies for reasonable management of solid wastes with a view to protecting Puerto Rico’s environment, public health and natural resources.

Each resident of Puerto Rico generates an average of 4.9 lbs of solid waste a day. The excessive production of waste on the island has completely exhausted 41 sanitation landfill systems and led to their closure. There are currently only 31 such systems in operation. Storage of wastes in landfills results in the production of lixiviates, among other contaminants, with the potential for impact on groundwater and surface water systems.

Air pollution results primarily from the island`s industrial activities, such as thermoelectric facilities, oil refineries, as well as cement and pharmaceutical factories. Contaminants from these sources include sulfur dioxide, carbon dioxide, nitrogen oxides, particulate matter, and polychlorate biphenyls (PCBs), among other substances.

Water pollution in Puerto Rico comes from both dispersed and point sources. Many of Puerto Rico’s sewage treatment plants and pumping systems are in a state of deterioration, and often release untreated sewage into the island’s bodies of water. Nearly half of the island’s resident do not have access to proper sewage facilities, and sewage winds up being discharged directly into lagoons, rivers and streams. Industrial activities have led to the contamination of groundwater, forcing aquifers to be sealed off given the impossibility of cleaning them.

Unchecked, the impact of these contaminants on the island’s natural resources and environment will continue to have detrimental effects both on present as well as future generations. It is our responsibility to thoroughly understand our environment so that we can defend it. We need to pass this knowledge on to our children, and to our grandchildren, so that Puerto Rico’s environmental awareness can be fortified. Efforts need to be instrumented on an individual and community level, so that action can replace mere rhetoric.

Desecheo, islet off the western coast of Puerto Rico

Desecheo, islet off the western coast of Puerto Rico

The islands and keys (or rocky promontories) that are adjacent to the principal island, Puerto Rico, contain many resources and provide shelter for a unique wild life. The largest of these islands are Culebra and Vieques, located to the east of the town of Fajardo. Other islands include Mona, Monito and Desecheo to the west, Deadman`s Chest to the south and the La Cordillera keys to the east (Icacos, Palominitos, Blanquilla, and Diablo keys, among others). Since these islands have hardly been impacted by humans, they have been used as natural research laboratories by local and international scientists and enyoined as an excellent location for recreational activities.

The islands of Culebra and Vieques share certain characteristics with the southern part of Puerto Rico, where there is less precipitation. The land and vegetation of these islands are that of a subtropical dry forest. Culebra has a total area of 7,700 acres and a topography ranging from plains to hills. The highest point is Monte Resaca, at 198 meters (650 feet). The 1480-acre Culebra refuge is located on the island and there are 23 smaller surrounding islands and rocky promontories projecting from the sea. The Luis Peña channel near Culebra, which has an extensive coral reef, has also been designated as a natural reserve.

The topography of Vieques is comprised of low lying hills and shallow valleys. The highest elevations are Monte Pirata, on the western side of the island, at 305 meters (1000 feet) and Cerro Matías on the eastern side, at 128 meters (420 feet). Vieques has some small river beds with no drainage, although it is believed that there may have been some rivulets in the past. There are also some intermittent brooks produced by rain water. Nearly 90% of the precipitation evaporates due to the high temperatures. The two main aquifers are those of the Valle de Resolución on the western part of the island and Valle Esperanza to the south. The island has a bioluminescent bay reserve.

The island of Mona is a very beautiful natural reserve of considerable ecological value. The natural sanctuary measures 14,043 cuerdas, about 13.6 acres, and is located 50 nautical miles off the west coast of Puerto Rico. The climate is dry and the island is classified as a semi-arid or dry region. The cliffs on Mona island extend vertically to depths of a 100 feet (30 meters) or more. The coasts are surrounded by reefs, including a barrier that protects the south coast of the island and which contains a rich variety of hard and soft coral. There are more that 19 large caves on the island, some of which are miles long and are decorated with Taino rock art (petroglyphs). Mona Island is a habitat of critical importance for endemic species, including the Mona iguana, which is protected by legislation as an endangered species.

Contaminated zone in La Parguera, Lajas

Contaminated zone in La Parguera, Lajas

Although the word “environment” refers to everything that surrounds us, including the physical environment that has been discussed, it is important to include the human environment as well. By this we mean how we as human beings relate to our surroundings. The negative impact of human activity bears emphasizing, but we also must not forget the important struggles to defend our natural heritage and the environmental legislation in effect since the second half of the 20th century.

During Spanish rule of the island, there was legislation that addressed the use and exploitation of natural resources, as well as city planning. When sovereignty changed hands in the 1898 Treaty of Paris, legislation of a similar nature promulgated by the United States Congress was implemented. This use and exploitation of resources has brought on the environmental problems that are associated with ill-conceived human intervention. The problems that afflict us most today are deforestation; the loss of species; pollution of our water, soil and air; and solid waste management.

Deforestation occurs with the clearing of trees or vegetation, and can have a negative effect on soil conservation and the equilibrium of natural systems. It is estimated that in the 16th century, Puerto Rico was almost completely covered with forests. There was constant deforestation during the 19th and early 20th century, principally due to the development of coffee and sugarcane plantations. By the middle of the 20th century, less than 5% of the island was covered by forests.

In the 1950s, development in Puerto Rico was organized under a model called Operation Bootstrap. Emphasis was given to creating jobs and providing industrial incentives, which resulted in the transformation of an agricultural economy into an industrial economy. Plantations were abandoned and agriculture collapsed. Agricultural land was used for grazing, and later for rapid growth trees.

Although during the past 60 years forest coverage on the island has decreased, deforestation is also growing along with urban expansion. Large-scale housing developments have had a negative effect on vast parcels of land where the vegetation is cleared. Forest clearance results in the loss of important habitats for plant and animal species that are unique to the island.

Environmental pollution refers to substances that are released into the air, the soil, and water in quantities that are intolerable to the system and that can affect the health of human beings and other species. Pollution can be caused by dispersed or non-dispersed sources. Dispersed sources are those in which contamination occurs by the emission of toxic substances in a disperse manner, not from a definite point, such as by burning trash or emissions from automobiles. Non-dispersed sources are those in which toxic substances are emitted into the air, water, or soil from well defined locations.

Air pollution is caused principally by industrial activity such as power plants, oil refineries, cement factories, and pharmaceutical plants. These sources produce sulfur dioxide, nitrogen oxide, and solid or liquid particulate suspended in the atmosphere (particles, aerosols, smoke). Pollution can also be caused by natural sources such as dust from the Sahara Desert and the eruption of volcanoes.

Water pollution is most common in surface bodies, but can also occur in underground water. Many sewage treatment plants and pump systems are deteriorated and discharge untreated sewage into the water system. Thousands of residents, nearly 50% of the population, are not connected to the sewage system, and discharge sewage into lagoons, rivers, and brooks. Some industries have contaminated underground water wells, which has forced their closure, because it is impossible to clean them.

The largest sources of pollution on the island are associated with industrial development that took place in the 1960s to the 1990s, based on pharmaceuticals, oil refineries, chemical plants, or chemical derivatives. This development increased the risk of chemical spills. In the last 32 years of the 20th century there were at least seven major spills or leaks of polluting substances that damaged natural resources, the quality of the water, the air and the soil, and the health of workers.

Solid waste management
Excessive production of solid waste on the island has lead to the closing of 41 landfill sites. The storage of waste in a landfill, among other pollutants, produces liquid acid known as leachate, which is a product of the decomposition of the waste, and can be washed away by rain and transported to surface and underground water bodies. The contaminants in this leachate depend on the materials in the decomposing waste.

The Solid Waste Authority (SWA) was created under Public Law 70, enacted on June 23, 1978 with a view to addressing this issue. The agency is in charge of evaluating, planning, and implementing strategies for a rational handling of solid waste in order to protect the environment, public health, and natural resources.

Sings and posters protesting the privatization of beaches

Sings and posters protesting the privatization of beaches

After the Second World War, the effects of industrialization drew attention to environmental and social issues. In the 1960s, efforts began to identify pollution issues: the need to establish controls, and address environmental problems from a comprehensive perspective.

Environmental movements developed on the island as they did on an international level. A key international event was the publication of the book Silent Spring (1962), whose author, Rachel Carson, brought to public attention the use of pesticides and their effects on wildlife. The best-selling book created awareness all over the world. Another worldwide event was the celebration of the First International Earth Day (1970) during which 20 million people protested against the deterioration of the environment.

In Puerto Rico there were struggles related to occupational and community health issues. In the 1970s there was an exposé of experimentation with Agent Orange in the El Yunque rainforest; and there were protests against mining in Adjuntas, Jayuya, Utuado and Lares (1964-1988) as well as opposition to the construction of nuclear energy plants in Manatí, Salinas, and Arecibo (1969-1976).

In the 1970s, there was a movement to oppose the construction of a superport in Aguadilla, Rincón, or Mona Island (1972-1973); demands were made to control pollution from graphite, tar gases, and hydrogen sulphide generated by Union Carbide Grafito in Yabucoa (1973-1985), and against the disposal of untreated waste by the tuna packers in Cabo Rojo (1976-1977), among other important protests.

Since the 1980s, the environmental movement has grown and become stronger through numerous legal actions. Many communities have won cases against polluting industries and other entities that are responsible for having a negative impact on health and environmental quality. Communities have also won the right to be informed, which has benefited the public at large.

Environmental protection agencies and legislation
Faced with demands being made by the public, the government was forced to address the environmental issues of the island. Legislation was passed to create government agencies with the mandate to regulate activities that affect the environment.

In 1952, public policy for the environment was established in the Constitution of the Commonwealth of Puerto Rico. In 1969, the United States Congress passed the National Environmental Policy Act, under which the Environmental Protection Agency (EPA) was created in 1970. In Puerto Rico, Public Law No. 9 was enacted on June 18, 1970 to implement public policy on environmental conservation and to create the Environmental Quality Board. Both laws require that all government bodies analyze and weigh the environmental impact of their decisions before they take any action. Public Law No. 9 was repealed and substituted by Public Law No. 416, enacted on September 22, 2004.

The Department of Natural and Environmental Resources (DNER) was created through Public Law No. 23 on June 20, 1972, to protect, preserve and administer the natural and environmental resources of the island in an equitable manner to guarantee the enjoyment of these resources by future generations. The DNER currently has jurisdiction on wildlife, state forests, natural reserves and wildlife refuges (including lakes or reservoirs), lagoons, and a part of Culebra and Vieques. The Department also has jurisdiction on property covered by eminent domain, such as water, fish, minerals, riverbeds, riverbanks and material in rivers, the maritime-terrestrial zone, territorial waters, and submerged land. This also includes natural resources and systems such as caves, caverns, sinkholes, mangroves, wetlands, and habitats that are of critical importance for wildlife and endangered species.

Towards a sustainable future
It is important to recognize the value of our natural resources, in order to conserve them. If we do not decrease the negative impact we have on our physical environment, there is no question that present and future generations will suffer the consequences. We must consider the alternatives for sustainable development, which can be achieved by using our resources without compromising their future.

Achieving a balance between the environment and economic development will be the challenge for all agencies. They must collaborate in finding the most equitable and effective solutions to the environmental problems of the island. It is of crucial importance for all that we foster an efficient use of our land and the restoration, conservation, and management of our natural resources.

Author: Prof. María Calixta Ortiz
Published: May 27, 2009.

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