Outlook on AGRICULTURE Vol 34, No 1, 2005, pp 11–21 11 Plantation agriculture in the tropics Environmental issues Alfred E. Hartemink Abstract: Plantation agriculture is more than 400 years old and contributes to the regional and national economies in many tropical countries. This paper reviews some of the main environmental issues related to plantation agriculture with perennial crops, including soil erosion, soil fertility decline, pollution, carbon sequestration and biodiversity. Soil erosion and soil fertility decline are of concern in some areas, but in most plantations these are being checked by cover crops and inorganic fertilizer applications. Few studies have been conducted on the issue of carbon sequestration under perennial plantation cropping. Reductions in deforestation yield much greater benefits for a reduction in CO 2 emissions than expanding plantation agriculture. The biggest threat to biodiversity is the loss of habitat through expansion of the plantation area. Despite the environmental problems and concerns, this review has shown that crop yields of most perennial crops have increased over time due to improved crop husbandry including high- yielding cultivars and improved soil management. It is likely that more attention will be given to the environmental aspects of plantation cropping due to the increasing environmental awareness in tropical countries. Keywords: plantation agriculture; soil erosion; soil fertility decline; biodiversity; environment; crop yield The author is Deputy Secretary-General of the International Union of Soil Sciences (IUSS) and a soil scientist at ISRIC – World Soil Information, PO Box 353, 6700 AJ, Wageningen, The Netherlands. E-mail: alfred.hartemink@wur.nl. Homepage: www.alfredhartemink.nl. Plantation agriculture started in the sixteenth century when the Portuguese settled in coastal parts of Brazil. The area lacked any known mineral wealth and settlers were involved in the cultivation of sugar cane, which would find a ready market in Portugal. Slaves were brought in from Portugal’s Atlantic island colonies, and during the sixteenth century Brazil was the world’s major supplier of sugar (Courtenay, 1980). This showed that large-scale agriculture in the tropics could be a successful business. There are a number of definitions of plantation agricul- ture, but it is often referred to as a large-scale, mostly foreign-owned and specialized high-input / high-output farming system that is export-oriented (Courtenay, 1980; Goldthorpe, 1987 and 1994). Tiffen and Mortimore (1988) defined plantation agriculture as a farm of over 100 ha in size, with a specialized management team in charge of a labour force with specialized production techniques. A more recent definition was given by Stephens et al (1998): Plantations are defined as areas that are typically monocropped with perennials, producing tropical or subtropical products that commonly require prompt initial processing and for which there is an export market. The term ‘plantation’ is also used in forestry: timber plantations, plantation forests or forest plantations (Evans, 1986; Parrotta, 1992; Sedjo and Botkin, 1997). Forest plantations are man-made forests where cultivation is generally less intensive. Forest plantations are defined as: ‘a forest crop or stand raised artificially, either by sowing or planting’ (Evans, 1992). The world plantation belt runs from Central and South America across the equatorial regions of Africa to Asia, to