Environmental Evaluation of Metals in Sediments and Dragonflies Due to Sugar Cane Cultivation in Neotropical Streams Juliano José Corbi & Susana Trivinho-Strixino & Ademir dos Santos Received: 6 March 2008 / Accepted: 11 May 2008 # Springer Science + Business Media B.V. 2008 Abstract The use of fertilizers, containing different metals ions such as lead(II), chromium(III), cadmium (II), copper(II) and zinc(II), in the soil, for sugar cane cultivation, may cause impacts on the hydric resour- ces of the adjacent areas. The scope of this study was to evaluate the impacts of sugar cane cultivation based on metal concentrations in sediments and dragonflies (Odonata). The bioavailability of such metals was determined in ten Neotropical streams. Six streams were located on areas with sugar cane cultivation, without riparian vegetation (classified as impacted area) and four streams were located on forested areas (reference sites). The results showed that there are high concentrations of metals in the sediments and dragonflies in streams located on impacted areas. The contamination by metals of aquatic insects of terrestrial adult life cycle, as Odonata organisms, represents a dangerous link for the transference of metals to upper trophic levels, as fishes, reptiles, birds and mammals. Keywords Metals . Streams . Dragonflies . Sugar cane cultivation . Sediments . Brazil 1 Introduction In Brazil, several regions of the native land cover vegetation were removed and substituted by agricul- ture, mainly of sugar cane. This process resulted in deforestation, especially in the Brazilian southeast region (Martins 2001). In Brazil, the sugar cane cultivation passed by different periods, always pre- senting an increasing of the cultivated area. In the last 15 years, sugar cane cultivation has been expanded, reaching more than 338 million tons/year (Carvalho Filho 2000), which transform the country in the main sugar and alcohol producer in the world, it corre- sponds to 27% of the worldwide production (Institute of Agro-industrial Development 1998). Sugar cane is the main source of sugar (sucrose) and alcohol production (through a fermentative sugar cane pro- cess). Alcohol is exported from Brazil to other countries and it has been also used as an alternative and renewable combustible for vehicles (Carvalho Filho 2000). In the last 5 years, other countries have shown interest for alcohol produced from sugar cane. Therefore, the trend is an increment for sugar cane production in Brazil and also in other countries. The use of small amounts of pesticides, in addition to the fast growth of the plant, facilitates the control of the erosive process, which is considered positive Water Air Soil Pollut DOI 10.1007/s11270-008-9749-1 J. J. Corbi (*) : S. Trivinho-Strixino Departamento de Hidrobiologia, Universidade Federal de São Carlos, CP 676, 13560-970 São Carlos, SP, Brazil e-mail: julianocorbi@yahoo.com.br A. dos Santos Departamento de Química Analítica, Instituto de Química de Araraquara, Universidade Estadual Paulista, CP 355, 14800-970 Araraquara, SP, Brazil