Effectiveness of Environmental Surrogates for the Selection of Conservation Area Networks

Abstract

Rapid biodiversity assessment and conservation planning require the use of easily quantified and estimated surrogates for biodiversity. Using data sets from Québec and Queensland, we applied four methods to assess the extent to which environmental surrogates can represent biodiversity components: (1) surrogacy graphs; (2) marginal representation plots; (3) Hamming distance function; and (4) Syrjala statistical test for spatial congruence. For Québec we used 719 faunal and floral species as biodiversity components, and for Queensland we used 2348 plant species. We used four climatic parameter types (annual mean temperature, minimum temperature during the coldest quarter, maximum temperature during the hottest quarter, and annual precipitation), along with slope, elevation, aspect, and soil types, as environmental surrogates. To study the effect of scale, we analyzed the data at seven spatial scales ranging from 0.01 • to 0.10 • longitude and latitude. At targeted representations of 10% for environmental surrogates and biodiversity components, all four methods indicated that using a full set of environmental surrogates systematically provided better results than selecting areas at random, usually ensuring that ≥90% of the biodiversity components achieved the 10% targets at scales coarser than 0.02 • . The performance of surrogates improved with coarser spatial resolutions. Thus, environmental surrogate sets are useful tools for biodiversity conservation planning. A recommended protocol for the use of such surrogates consists of randomly selecting a set of areas for which distributional data are available, identifying an optimal surrogate set based on these areas, and subsequently prioritizing places for conservation based on the optimal surrogate set. Efectividad de Sustitutos Ambientales para la Selección de Redes deÁreas de ConservaciónResumen: La evaluación rápida y la planificación de la conservación de biodiversidad requiere del uso de sustitutos de la biodiversidad fácilmente estimados y cuantificados. Utilizando datos de Québec y Queensland, aplicamos cuatro métodos para evaluar el grado en que los sustitutos ambientales pueden representar a los componentes de la biodiversidad: (i) gráficos de subrogación; (ii) parcelas de representación marginal; (iii) función de distancia Hamming; y (iv) prueba estadística de Svrjala para congruencia espacial. Para Québec, utilizamos como componentes de biodiversidad a 719 especies de fauna y flora, y para Queensland utilizamos 2348 especies de plantas. Consideramos como sustitutos ambientales a cuatro tipos de parámetros climáticos (temperatura media anual, temperatura mínima durante el trimestre más frío, temperatura máxima durante el trimestre más cálido y precipitación anual), la pendiente, la altitud, el aspecto y los tipos de suelo. Para estudiar el efecto de la escala, analizamos los datos en siete escalas espaciales que variaron de 0.01 • a 0.10 • de longitud y de latitud. En representaciones dirigidas a 10% de los sustitutos ambientales y los componentes de la bio...

Global meta-analysis reveals low consistency of biodiversity congruence relationships

“…Although the influence of spatial and biogeographic parameters on cross-taxon congruence was limited, it is clear that the spatial scale of a study-and, to a lesser extent, its latitude-has a role in determining the extent of congruence observed in that investigation 34 . This important result extends an array of earlier work, showing that the scale at which studies are conducted can influence study outcomes, such as the distribution of biodiversity hot spots 7,12 , or the relationship between species distributions and underlying environmental parameters 48,49 . It also suggests a need for caution when synthesizing research on processes that vary across spatial scales.…”

Plant functional types and traits as biodiversity indicators for tropical forests: two biogeographically separated case studies including birds, mammals and termites

“…Thus forest biodiversity surveys still maintain a taxonomic focus even though the costs of obtaining sufficient sampling can be high and the utility of any one species, or another single taxon, as a predictor of others remains uncertain (Lawton et al 1998;Watt et al 1998;Dufrêne and Legendre 1997;UNEP/CBD 2003;Gregory et al 2005, but see also Schulze et al 2004). Further, at large spatial scales where within-region diversity is large, higher level taxa (up to family level) must often be used (Villaseñor et al 2005), but even this is only justifiable where extensive species data are already available (Sarkar et al 2005). Such difficulties in forests contrast with intensively sampled, relatively species-poor, temperate agricultural lands where single surrogate species may be indentified (e.g.…”

Intraspecific morphological and genetic variation of common species predicts ranges of threatened ones

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