ICMM - International Council on Mining & Metals

CASE STUDY

Studying a botanical gold mine

Background

At 2.35 million hectares, the Lorentz World Heritage Area (WHA), located in the Indonesian Province of Papua on the island of New Guinea, is the largest reserve in Southeast Asia. Its remote location and difficult logistics within the park greatly limit research there, and few detailed botanical studies have been made in the Lorentz since exploration of the area in the early 1900s. One major source of ecological information essential for sustainable park management comes from studies in nearby areas within the PT Freeport Indonesia (PTFI) Project area. This information is directly applicable for understanding the biodiversity of the Lorentz WHA.

Biodiversity in Freeport’s Area of Work

Over many years Freeport has funded a series of comprehensive surveys of the area’s biodiversity. The first studies were conducted as part of a major expansion. In addition to lowland, montaine, subalpine, alpine and nival plants, detailed surveys have included aquatic and terrestrial insects, freshwater fishes, amphibians, reptiles, birds and mammals. This work produced an 11-volume series describing the effort and its results. Subsequent work has included surveys of plants, estuarine fishes and invertebrates, birds and mammals and butterflies of the area. These surveys have involved scientists from a number of major Indonesian academic and scientific institutions, with assistance from internationally respected organisations such as the Royal Botanic Gardens, Kew, the Smithsonian Institute, the Bishop Museum and the Australian National Museum.

Plant Project

As with the rest of southern New Guinea, the PT Freeport Indonesia Project area supports one of the highest plant diversities identified in any region of the world. This diversity occurs within a 120-kilometre range, from the south coast on the Arafura Sea to the ice-capped summit of Mt Jaya – as wide a range of plant habitats as found from the equator to the poles.

The Plant Project was initiated following the comprehensive plant work done as part of the Grasberg expansion. The original objective of the Plant Project, involving the Royal Botanic Gardens, Kew, was to collect all the vascular plants in the Freeport Project area and produce a comprehensive species list.

With the high diversity encountered, the detailed museum collecting has taken more time than anticipated and so far has been mostly focused on high-altitude flora. With more than 650 species of vascular plants in the alpine and subalpine zone, the diversity of the high-altitude flora already exceeds that of the flora of Ireland. Included are many endemics recorded only from Mt Jaya (the highest peak between the Himalayas and the Andes), the province of Papua, or the island of New Guinea. The collections include many species that are not yet represented in the Herbarium Bogoriense or at the Royal Botanic Gardens, Kew or other herbaria.

Actual figures for the diversity of plants in Freeport’s work area are not available, but preliminary studies and collections indicate a probable diversity of 8,000-8,500 plant species. Because of its large area, plant diversity in the Lorentz WHA is anticipated to be even greater.

Assistance in Reclamation

The development of the Grasberg pit has resulted in overburden being deposited in highland overburden placement areas immediately surrounding the Grasberg, and tailings being deposited in the designated tailings deposition area, both operated under Government of Indonesia approval. Concurrent with the increased production associated with the Grasberg and underground operations development, PTFI substantially expanded its environmental commitments.

Freeport’s commitment to reclaim overburden and tailings areas is aided by the detailed studies of the local flora. In addition to information useful in the eventual reclamation of disturbed areas, potential applications of results from these botanical studies are enormous. The studies include research with applications related to theoretical problems, taxonomic problems, local speciation patterns, and important conservation issues.

Five distinct vegetation zones are contained within the mining operation’s project area. At high altitudes, overburden covers areas adjacent to the Grasberg complex. Here local species are used to establish a diverse alpine and subalpine plant community.

In the lowlands, management of the tailings deposition area requires reclamation that will use local species. Tailings may eventually affect areas of lowland rain forest, lowland swamp forest, mangroves and coastal forest contained within the deposition area. Successful reclamation management requires a detailed knowledge of the major plant species in the area. New areas of tailings deposition are already being colonised by local species through natural process; in addition, PTFI accelerates this process through assisted plant colonisation programmes. Research at the PTFI Maurujaya Reclamation Centre, in addition to field studies of plant growth, also contributes important information to the reclamation effort.

Conclusions

There have been few detailed studies of the vascular plants in eastern Indonesia. The collection and inventory of species from PT Freeport Indonesia’s Project area have greatly enhanced the value of national and regional herbaria and the living collections in the Botanic Gardens in Indonesia, allowing a better taxonomic understanding of the species collected from this poorly known region. Important for Freeport, the collections continue to provide information important for reclamation of overburden and tailings. The partnership’s efforts also provide a better knowledge of the plant species of the Lorentz World Heritage Area, an important tool for the management and conservation of biodiversity there.