Exploring the Relationships between Key Ecological Indicators to Improve Natural Conservation Planning at Different Scales

Abstract

Biodiversity, regulating ecosystem services (RES), and vegetation productivity are key indicators to instruct natural conservation planning. Decision makers often hope that ecosystems can be protected by focusing on certain key indicators, which requires an understanding of the relationships between the indicators. Using individual case studies, many have argued that these indicators commonly have significant relationships. However, these relationships at different spatial scales are unclear. Therefore, in this study, biodiversity and ecosystem services are modelled by the ecological niche model, the universal soil loss equation, and the equation of water balance in two study areas at different scales. The influence of vegetation productivity on the spatial pattern of other ecological indicators in the two areas is examined by a spatial lag model. The contributions of the driving factors on biodiversity distribution at both scales are identified by a boosted regression tree (BRT) model. The results showed that at the fine scale, the spatial correlations were strongest for species richness, especially mammalian species richness, and water retention. However, biodiversity had no significant relationship with vegetation productivity. In contrast, at a coarser scale, the correlation was stronger between plant diversity and regulating ecosystem services. In addition, plant diversity was significantly correlated with vegetation productivity. These differences between scales were controlled by various explanatory variables. At the fine scale, biophysical and climatic factors had the strongest effects on biodiversity distribution, while Net Primary Productivity (NPP) and ecoregion also had relatively high influences on biodiversity at the coarse scale. This demonstrates the critical importance of spatial scale in selecting conservation indicators. We suggest that rare mammalian species richness or flagship mammal species are suitable as conservation surrogates in fine-scale conservation planning. However, at a coarser scale, selecting vegetation patches with more rare plant species and high productivity for each ecoregion is a workable alternative method for conservation planning.

Productivity correlates positively with mammalian diversity independently of the species’ feeding guild, body mass, or the vertical strata explored by the species

“…Qian 2010), net primary production (10 studies, e.g. Zhang & Ouyang 2019), plant cover (five studies, e.g. Kimuyu et al 2017), elevation (21 studies, e.g.…”

“…Productivity can be defined as the rate of energy flow to an ecological system (Abrams 1995, Rosenzweig 1995, Waide et al 1999, Gaston 2000, Mittelbach et al 2001). Researchers have found different relationships: there are positive (Kaufman & Willig 1998, Ferreira Neto et al 2021b), negative (Peres 1997, Zhang & Ouyang 2019), unimodal (Ganzhorn et al 1997, Gebert et al 2019), U‐shaped (Shepherd 1998, Chen et al 2020), and even non‐significant relationships between productivity and diversity (Williams & Marsh 1998, Ramírez‐Bautista & Williams 2019). Depending on the underlying mechanism, hypotheses relating to productivity may also be mediated by the spatial extent investigated, which may also explain variation in diversity patterns (Currie 1991, Chase & Leibold 2002, Hawkins et al 2003, Gonzalez‐Megias et al 2007, Veech & Crist 2007, Hortal et al 2008, Swan et al 2020).…”

Biodiversity Conservation in Managed Forests

“…Zheng and Ouyang [1] use a variety of modelling approaches to assess the usefulness of key indicators of biodiversity in forests for conservation planning. A key part of their analysis is an evaluation of the relationships between key indicators and biodiversity at different spatial scales.…”