Influence of eucalyptus plantations on benthic macroinvertebrate assemblages in neotropical springs

Abstract

Aim The high sensitivity of springs to anthropic impacts is largely due to the high existing aquatic-terrestrial connectivity. The degradation of these ecosystems can be caused by land use, such as eucalyptus monoculture. The aim of this study was to test the influence of Eucalyptus urograndis plantations on the richness and diversity of the benthic macroinvertebrate community and on the environmental variables measured in springs in the Atlantic Forest domains. Methods Ten springs (5 in native forest areas and 5 in eucalyptus area) were sampled in the dry period of 2017. The organisms were screened and identified at the family level. For each spring, dissolved oxygen, temperature, pH, turbidity, electrical conductivity, total dissolved solids, total nitrogen, nitrite, nitrate, ammonia, total phosphorus, vegetation cover, granulometric characterization and organic matter were also measured. Results: The t-test showed that some environmental variables differed, with the eucalyptus areas having higher values of total dissolved solids and electrical conductivity, and lower values of coarse sand. In the present study, the richness and diversity of the benthic fauna of springs were significantly lower in eucalyptus sites than in native sites. Nonetheless, the composition of the communities did not differ. The Indicator Species Analysis (IndVal) associated Acari, Hydropsychidae, Leptoceridae, Nematoda, Psychodidae, and Tipulidae with areas of native forest. Conclusions Our results show that Brazilian springs are affected by eucalyptus monocultures reducing the richness and diversity of benthic macroinvertebrates and also changing water environmental properties. Thus, we verified that previous studies elsewhere in the world also apply to neotropical areas where eucalyptus is not native.