The response of neotropical dragonflies (Insecta: Odonata) to local and regional abiotic factors in small streams of the Amazon

Since the relative role of local and regional abiotic factors on the Odonata diversity in rainforest streams is still poorly understood, we evaluated the effects of these factors on adult Odonata (Insecta) from preserved and altered streams in the Amazonian region. Adult Odonata were sampled in 98 streams in the Eastern Amazon, Pará, Brazil. Six variables were used to measure local environmental factors: habitat integrity index; mean canopy over the channel; and four physical and chemical descriptors of the water. To measure regional environmental factors, six variables were also used: altitude gradient, three bioclimatic variables and two percentage forest variables. In partial redundancy analysis, both abiotic factors (local and regional) were important to explain the variation in the Odonata community. The Odonata community can be influenced by regional and local factors. The relationship between Odonata and the local (e.g., integrity, canopy cover, and physical and chemical descriptors of the water) and regional (e.g., bioclimatic and forest cover variables) environmental variables recorded in this study has important implications for the use of these organisms to monitor small streams of the Eastern Amazon. The scale at which habitat is measured is an important issue in community structuring studies considering the rapid environmental changes. It is of great importance to consider the different scales in studies assessing community structure, once an adequate habitat must meet the ecological needs of all stages of the life of the Odonata.Funding Agency National Council for Scientific and Technological Development (CNPq) CNPq Amazonian Biodiversity and Land Use project CNPq 574008/2008-0 Brazilian Agricultural Research Company-EMBRAPA SEG: 02.08.06.005.00 Darwin Initiative, United Kingdom 17-023 Nature Conservancy and Natural Environment Research Council (NERC) NE/F01614X/1 NE/G000816/1 National Council for Scientific and Technological Development (CNPq) 307597/2016-4 Portuguese Foundation for Science and Technology UID/Multi/04326/2019 PROPESP/UFPA through Edital 01/2018 (Programa de Apoio a Publicacao Qualificada-PAPQ)