AAAS ATLAS OF POPULATION AND ENVIRONMENT

he Dominican Republic occupies the eastern part of the island of Hispaniola in the Caribbean Sea. Covering nearly 50 000 square kilometers, this island nation encompasses a broad array of environmental zones, from the pine-covered slopes of the highest peak in the Caribbean to dense webs of mangroves along large stretches of its coasts.

Much of the surface of the Dominican Republic today is dominated by agriculture, practiced on a small scale by the native Taino Indians when Christopher Columbus arrived there in 1492, but now much more extensive. Known especially for its sugar production, the Dominican Republic also produces coffee, cocoa and rice, along with other crops of lesser importance and livestock. In recent decades, tourism and manufacturing have come to dominate the economy.

The demography of the Dominican Republic has changed considerably since the arrival of Europeans in the 15th century. Disease and maltreatment, both from the Spanish, virtually eradicated the indigenous population by the early 1500s. In response the Spanish brought slaves from Africa to replace the indigenous peoples as a source of labor. Due primarily to continuing in-migration, the population began to grow – slowly at first, then more rapidly. By the time of its first systematic census in 1920, roughly 890 000 people lived in the Dominican Republic. Steady population growth occurred over the ensuing seven decades, resulting in a total population of about 7.3 million in 1993, the date of the most recent census. Natural increase, augmented by slight in-migration, has fuelled this population growth. Between the most recent two censuses of 1981 and 1993, population was still growing on average at a rate of 2.3 percent per year. But the most noteworthy characteristic of the country’s demographic change in the past three decades has been internal migration, primarily from rural areas to cities, leading to dramatic shifts in the geographic distribution of people in this island nation.

As home to more than 30 national protected areas, the conservation of the natural environment is a major consideration in the Dominican Republic. One of the most important components of conservation is freshwater, most of which originates as rainfall in the central mountain chain that runs east-west across Hispaniola. Fulfilling demands for domestic use in major cities along the coast, freshwater also plays a key role in maintaining all ecosystems on the island and contributes to various economic activities, most notably agriculture. The more than 100 major watersheds in the Dominican Republic can be classified as to their general condition through an examination of satellite imagery to measure the amount of vegetation disturbance in each. Comparing these levels of disturbance to population levels reveals a general correlation between the number of people residing in a watershed and its condition – that is to say, the watersheds in poorest condition tend to be those with the largest populations. However, this association is not perfect. In some cases, heavily disturbed watersheds contain fewer people, while in other cases watersheds with minimal disturbance contain high populations. The former condition tends to occur in areas of high agricultural activity, the latter in areas with less agricultural activity and populations concentrated in a few main settlements. Through the further study of how humans and human activity are spatially distributed across the Dominican Republic, researchers and government planners can better understand how people affect freshwater and how this key resource can be conserved and used more wisely in this small island nation.