Assessing the ecological impact of banana farms on water quality using aquatic macroinvertebrate community composition
(English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026Article in journal (Refereed) Submitted
In Costa Rica considerable effort goes to conservation and protection of biodiversity while at the same time agricultural pesticide use is among the highest in the world. Several protected areas, some being wetlands or marine reserves, are situated downstream agricultural areas where large-scale banana farms constitute a major land use, with an average of 57 pesticide applications per year. The banana industry is increasingly aware of the need to reduce their negative environmental impact, but few ecological field studies have been made to evaluate the efficiency of proposed mitigation strategies. This study evaluated if benthic macroinvertebrate community structure is sensitive enough to detect environmental impact of banana farming, and thereby usable to measure improvements in pesticide management practices. Aquatic invertebrate samples were collected at 13 sites between March and April 2007, using kick-net sampling. Samples were taken both up- and downstream banana farms in fast flowing streams, with mostly cobbles for substrate in runs and riffles. The changes in community composition were measured at the family level using ordination methods. Additionally, the Biological Monitoring Working Party (BMWP) score system was applied along with a number of community composition descriptors. In total, 2890 specimens were collected, belonging to 14 orders and 49 families or taxa. The results support the hypothesis that surface waters immediately up- and downstream large-scale banana farms have different macroinvertebrate community compositions, with fewer sensitive taxa according to the BMWP-score values at the downstream sites. Rapid assessment using macroinvertebrate community composition thus appears to be a possible means to detect negative impact from chemical-intense agriculture. As the method is moderately time-consuming, low-cost and highly ecologically relevant it could become a useful complement to chemical analysis of pesticide residues in environmental risk assessment.
Costa Rica, banana production, aquatic benthic macro invertebrate, water quality
Research subject Ecotoxicology
IdentifiersURN: urn:nbn:se:su:diva-61850OAI: oai:DiVA.org:su-61850DiVA: diva2:438179