Polinização café

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Biodiversity and Conservation 13: 1245–1255, 2004. # 2004 Kluwer Academic Publishers. Printed in the Netherlands.

Services performed by the ecosystem: forest remnants influence agricultural cultures’ pollination and production
´ PAULO DE MARCO JR.* and FLAVIA MONTEIRO COELHO
Lab. Ecologia Quantitativa, Dep. de Biologia Geral, Universidade Federal de Vicosa, Postal Code ¸ 36571-000, Brazil;*Author for correspondence (e-mail: pdemarco@mail.ufv.br; fax: +55-31-38992549) Received 14 June 2002; accepted in revised form 5 May 2003

Key words: Coffee, Ecosystem service, Pollination, Production Abstract. Ecosystem services are natural functions of an ecosystem that can be, secondarily, used for the benefit of humans. A recent estimate showed that ecosystem services equal, on average, 33trillion dollars a year, with pollination being responsible for 112 billions dollars. The alteration of natural systems and the loss of pollinating species have caused a decrease in many crops’ productivity. The objective of this work is to evaluate the pollination as an ecological service in agriculture, testing the hypothesis that the presence of forest remnants increases coffee agriculturalproductivity through an increase in pollination. This argument is based on the assumption that areas of preservation of native forest required by Brazilian law provide pollinators to local agroecosystems. Fruit production was compared among three different planting regimes: agrosilviculture, and conventional monoculture with and without preserved forest remnants nearby. The average flower production bybranch was different among the farms and was not related to the planting methods. The first flowering was larger than the second, representing 81–98% of the flowers’ total production. The farms near forest fragments had an increase of 14.6% in production that can be related to the pollinating services.

Introduction Ecosystems are complex biological structures that involve biotic interactions andclose dependence of organisms with abiotic factors. Based on the Biotic Integrity theory approach (Karr 1981; Angermeier and Karr 1994), ecosystems are considered functional groups composed of elements and processes (Keddy and Lee 1993). The elements are the biological species which can be organized according to the functions they have in the system (i.e. their trophic level). The processes, orfunctions, are the ecosystem mechanisms directly related to species maintenance (e.g. nitrogen fixation by micorhyzae increasing the maintenance of plant species in nitrogen-poor soils). Ecosystem services are natural functions that can be, secondarily, used for human benefit (Costanza et al. 1997; Fearnside 1998; Masood and Garwin 1998; Altieri 1999; Daily 1999). These services involve biological,chemical and geological processes (Kearns et al. 1998) and include nutrient recycling, water and gas regulation, biological control, genetic resources, pollination as well as the scenic beauty explored in ecotourism. Of the current angiosperm flora, estimated at 25 000 species, about 90% are pollinated by animals, especially insects (Costanza et al. 1997; Chichilnisky and

1246 Heal 1998; Kearns etal. 1998). The human-domesticated animals depend, directly or indirectly, on pollination for approximately 1/3 of their food. A recent estimation shows that the services performed by the ecosystem equal 33 trillion dollars a year, with pollination being responsible for 112 billion dollars (Costanza et al. 1997). Independent estimates show that the annual value of agricultural pollination is 20– 40billion dollar in the USA alone. For global agriculture this value ranges around 200 billion dollars (Kearns et al. 1998). Many characteristics associated with modern agriculture make the agricultural habitats poor for pollinators because they do not provide all the necessary resources for survival, such as places for nesting, food and other physical conditions (Heard 1999). Natural systems...
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