Noel Kempff Mercado National Park covers 750,000 hectares of land, much of which consists of the Serrania de Huanchaca. The park is located on the Brazilian Shield in the northeast Santa Cruz Department in Bolivia. The Rio de Itenez is its eastern and northern border separating it from the neighboring Brazil. It adjoins the Serra Ricardo Franco State Park, created in 1997, in the state of Mato Grosso, Brazil. It is situated in a transition zone where the Madeira-Tapajós moist forests, Chiquitano dry forests, and Cerrado savannas meet. The park is made up of five distinct habitats, including upland evergreen forest, deciduous forest, upland cerrado savanna, savanna wetlands, and forest wetlands. The region has a marked dry season in the winter and a mean annual precipitation of 1,500 mm.
History
In 1908, Percy Fawcett first explored the area that is now the national park. It was not until almost 70 years later that the area was looked at again. In the 1970s geologists were sent to the area to survey the rock formations of the Precambrian Shield region in Bolivia. They published on the geology and landforms and produced the first maps. This expedition attracted the attention of conservation biologist Noel Kempff Mercado. Mercado recognized the global significance of the area enough to propose a campaign to preserve it. Mercado was murdered by drug traffickers in 1986, before the campaign achieved its aims. The government declared a 750,000 hectare area of undisturbed land as a national park in 1988, and named it in his honour.
Climate
The climate in the national park is seasonal, with approximately 1400-1500mm of mean annual precipitation. There is a dry season of about 4–6 months, when rainfall declines. Precipitation occurs mostly in the austral summer, originating from deep-cell convective activity over the Amazon basin and southerly extension of the Intertropical Convergence Zone. The mean annual temperature is 25-26 C but during the dry season temperatures can drop to 10 degrees C for several days when cold dry Patagonia air masses reach the park. Since the mid-Holocene, there has been a progressive vegetation succession from savanna to semi-deciduous forest to evergreen rain-forest in the region, attributed to increased annual precipitation and a shorter dry season. This expansion of rainforest has occurred over the last three millennia. Climate change could reverse this expansion of tropical rainforest. A drier climate could lead to an increase in fire frequency, allowing for an ecological shift of rainforest to dry forest. Should this happen there is a possibility some rainforest species could become extirpated from the region.
Soil composition
The Huanchaca Plateau within the park is 600–900 m above sea level and is composed of pre-Cambrian sandstone and quartzite of the Brazilian Shield. There are patches of evergreen forest on the soils that are deep and nutrient rich in the Plateau. Deep fertile soils support forest, while heavily weathered sandstone rocks with a thin layer of soil sustain open savannah. The adjacent low land plain to the west is blanketed by Cenozoic alluvial sediments and dominated by wet rain forests which transition into dry forests at the southern border of the park.
Flora
It is estimated that the park is home to approximately 4,000 species of vascular plants, including bromeliads, passion flowers, heliconias, aroids, and palms. Trees include the mahogany. The park includes portions of three ecoregions – the Madeira-Tapajós moist forests in the north and the Cerrado and Chiquitano dry forests in the center and south. The park encompasses five major ecosystems ranging from Amazonian rain forest, gallery forest and semi-deciduous tropical forest to flooded savanna and dry cerrado. So far, 2705 different species of plants have been identified. Because there is such a wide range of different habitats that exist in the park, this number is split into different sections of the park. 1500 of the 2705 plants exist in moist forest, 800 in cerrado, 700 in dry forest, 500 in savanna wetlands, and another 500 in aquatic and disturbed habitats, and rock outcrops. In addition to the 2705 plants that have already been identified, there are still 6000 being evaluated. The most diverse family out of all the taxa in the national park is the family Leguminosae. This family occurs in all ecosystems and in virtually all life forms except as epiphytes. Certain families of species thrive in all the park's habitats, such as the Rubiaceae, Melastomataceae, Bignoniaceae, and the Apocynaceae. Other species do better in specific habitats such as the cerrado or in savanna wetlands. Most species reach their greatest diversity in evergreen forests. A study on pollen cores has shown though that the evergreen forests found in the park did not always exist in that form. Data collected from pollen core samples has shown that what is now semideciduous and evergreen forest used to be savanna and semideciduous forest. The reason for this change in the mid-holocene was due to a gradual increase in mean annual precipitation and a decrease in the length and severity of the dry season.
Fauna
The park is also home to more than 130 species of mammals, 620 species of birds, and more than 70 species of reptiles, including the black caiman. The amphibians and reptiles of the park are among the most diverse in the Americas. There are approximately 127 species known from the park and adjacent areas and with a greater collecting effort, this number is very likely to increase. The large diversity in species is attributable to the location and the intricate pattern of diverse habitats in the park. About half of the amphibians and reptiles are mostly Amazonian species with the remaining species associated primarily with southern and eastern open formations. There are several reptile species listed by the Convention on International Trade in Endangered Species of Wild Fauna and Flora including species that are endangered in their home ranges. These include such species as Eunectes murinus, Eunectes notaeus, Caiman crocodilus yacare, Melanosuchus niger, Podocnemis unifilis, Podocnemis expansa, Geochelone carbonaria and Geocheolone denticulate.
Waterfalls
The cliffs of Huanchaca Plateau rise up to tall and in many locations there have formed waterfalls. These include the Arcoiris Falls, Frederico Ahlfeld Falls, and the El Encanto Falls.
Conservation
The national park was designated a World Heritage Site by the United Nations Educational, Scientific and Cultural Organization in 2000. Its importance is partially because the vegetation is almost pristine, with only minor human impacts from minimal logging activity experienced in the 1980s. The park encompasses the Huanchaca Plateau, which is one of the largest protected tracts of undisturbed cerrado savannahs in the Neotropical realm. This area has some of the most threatened mega-fauna in the Americas, including Ozotoceros bezoarticus, Blastocenus dichotomus, Chrysocyon brachyurus, Rhea americana, and Myrmecophaga tridacyla.
