Arthropods as surrogates of diversity at different spatial scales

Abstract

a b s t r a c tThis study evaluates the effectiveness of taxonomic, colonization and trophic groups of arthropods from native forests of the Azores archipelago as surrogates of the diversity of other arthropod groups and of the remaining arthropods. Consistency in the performance of surrogates was tested across three spatial scales and using two measures of diversity. Pitfall and beating samples from 109 transects, 18 forest fragments and seven islands were analysed. The results showed that Araneae, Hemiptera and small orders taxonomic groups; native, endemic and introduced colonization groups; and the herbivores trophic group were consistent surrogates of the remaining diversity across the three spatial scales analysed, for both alpha and dissimilarity diversities. However, none of the subsets considered was significantly related with all of the other subsets at any of the three spatial scales. The effectiveness of surrogacy was dependent on the spatial level considered, and groups behaved inconsistently depending on the measure of diversity used. The value of a group as a diversity surrogate should be evaluated for a study area for a given spatial scale and diversity measure, in accordance with the scale and measure that will be used for biodiversity assessments and monitoring programs in that area.

Selection of priority areas for arthropod conservation in the Azores archipelago

“…Thus, for up to a medium representation of species, some caution is needed when selecting a given group for study and to infer the optimal solutions for other groups. The use of surrogates for reserve selection is addressed elsewhere (Gaspar et al 2010), but from the present study it is possible to observe that the optimal solutions of different groups within each category do not correspond with each other. Additionally, the solutions for subsets do not agree with the optimal solutions for the overall dataset.…”

“…The Azorean Laurisilva is characterized by a dense cover of shrub and tree species of small stature, a rich cover of bryophytes, low understorey light and high levels of humidity. It has a high proportion of endemic vascular plant and invertebrate species (mostly arthropods and molluscs), while vertebrates (many introduced) are poorly represented (see Borges et al 2005bBorges et al , 2010.…”

Substitutos Da Diversidade: Funcionalidade E Limitações

“…A riqueza de Aranae e Hemiptera do arquipélago de Açores apresentou correlação com a riqueza de Coleoptera, Julida, Lepidoptera, Psocopterae, Thysanoptera (Gaspar et al 2010), assim como foi verificada congruência entre a riqueza de formigas predadoras e não predadoras da Colômbia (Cabra-García et al 2012). Em ambientes aquáticos, por sua vez, foi observado que a riqueza de espécies de moluscos de costões rochosos da Austrália é congruente com a riqueza de outros macroinvertebrados da região (Gladstone 2002), e a riqueza de espécies de besouros aquáticos apresentou correlação com a riqueza de Plecoptera, Trichoptera, Mollusca, Heteroptera e Ephemeroptera em ambientes lóticos e lênticos do Mediterrâneo (Sánches-Fernández et al 2006).…”

“…Uma vez que vários estudos têm comprovado que a riqueza é altamente variável entre diferentes táxons e entre locais, outras medidas de diversidade têm sido sugeridas, na tentativa de obter resultados mais consistentes para o desenvolvimento de substitutos da diversidade (Gaspar et al 2010). Entretanto, outras medidas de diversidade são aplicáveis, exclusivamente, para a abordagem de bioindicadores de diversidade, já que são medidas que relacionam parâmetros de diferentes comunidades.…”

“…Mais recentemente, a similaridade entre a composição de espécies de pares de grupos de diferentes áreas vem sendo investigada (Gaspar et al 2010), sendo possível avaliar qual comunidade apresenta maior diversidade (Magurran 2004). As comunidades podem ser consideradas equivalentes em termos de diversidade quando suas estruturas (α-diversidade) estão correlacionadas (Landeiro et al 2012).…”