Does catchment geodiversity foster stream biodiversity?

Abstract

Context One approach to maintain the resilience of biotic communities is to protect the variability of abiotic characteristics of Earth’s surface, i.e. geodiversity. In terrestrial environments, the relationship between geodiversity and biodiversity is well recognized. In streams, the abiotic properties of upstream catchments influence stream communities, but the relationships between catchment geodiversity and aquatic biodiversity have not been previously tested. Objectives The aim was to compare the effects of local environmental and catchment variables on stream biodiversity. We specifically explored the usefulness of catchment geodiversity in explaining the species richness on stream macroinvertebrate, diatom and bacterial communities. Methods We used 3 geodiversity variables, 2 land use variables and 4 local habitat variables to examine species richness variation across 88 stream sites in western Finland. We used boosted regression trees to explore the effects of geodiversity and other variables on biodiversity. Results We detected a clear effect of catchment geodiversity on species richness, although the traditional local habitat and land use variables were the strongest predictors. Especially soil-type richness appeared as an important factor for species richness. While variables related to stream size were the most important for macroinvertebrate richness and partly for bacterial richness, the importance of water chemistry and land use for diatom richness was notable. Conclusions In addition to traditional environmental variables, geodiversity may affect species richness variation in streams, for example through changes in water chemistry. Geodiversity information could be used as a proxy for predicting stream species richness and offers a supplementary tool for conservation efforts.

Lakes in the era of global change: moving beyond single‐lake thinking in maintaining biodiversity and ecosystem services

“…Positive relationships have been observed between biotic (biodiversity) or abiotic (geodiversity) attributes and ecosystem service supplies, suggesting that enhancement of joint biodiversity and geodiversity conservation should improve production of ecosystem services (Nelson et al ., 2009; Cardinale et al ., 2012; Harrison et al ., 2014; Isbell et al ., 2017; Alahuhta et al ., 2018). This approach may also be useful for understanding biodiversity variation across freshwater ecosystems (Kärnä et al ., 2019; Toivanen et al ., 2019).…”

Linking Terrestrial and Aquatic Biodiversity to Ecosystem Function Across Scales, Trophic Levels, and Realms

“…Inland aquatic and terrestrial environments do not exist in isolation; the abiotic environment in the surrounding watershed will impact the productivity of a water body (Likens 1975;Allan 2004) (Figure 2D), and in certain cases the abiotic conditions of a water body have been shown to affect the productivity of the surrounding terrestrial landscape [e.g., floodplains (Junk et al, 1989;Bayley 1995)] (Figure 2E). The abiotic characteristics of terrestrial and inland aquatic landscapes are also known to influence biodiversity directly (Wallace et al, 1997;Dahlin et al, 2013;Kärnä et al, 2019) (Figures 2F,G). Productivity is often correlated across terrestrial and aquatic realms, with highly productive terrestrial systems adjacent to productive aquatic systems (Wallace et al, 1997;Ballinger and Lake 2006;Gratton et al, 2017) (Figure 2H).…”

Spatial scale determines how the morphological diversity relates with river biological diversity. Evidence from a mountain river in the central Chilean Andes

“…Furthermore, temporal and spatial scales of connectivity are currently considered as major drivers in the development of ecological functions in rivers (Poeppl et al, 2020). Ecological conditions and diversity in river systems depends on the degree of relations between the biotics and abiotic components, and within biotic communities, which are often assessed based on benthic macroinvertebrates (Thomson et al, 2004), although other groups such as diatoms, aquatic macrophytes, fish and terrestrial invertebrates should be taken into account as indicators for the overall river ecological and environmental conditions (Friberg et al, 2009;Golfieri et al, 2015;Kärnä et al, 2019).…”