The ecological role of permanent ponds in Europe: a review of dietary linkages to terrestrial ecosystems via emerging insects

Abstract

Permanent ponds are valuable freshwater systems and biodiversity hotspots. They provide diverse ecosystem services (ES), including water quality improvement and supply, food provisioning and biodiversity support. This is despite being under significant pressure from multiple anthropogenic stressors and the impacts of ongoing global change. However, ponds are largely overlooked in management plans and legislation, and ecological research has focused on large freshwater ecosystems, such as rivers or lakes. Protection of ponds is often insufficient or indirectly provided via associated habitats such as wetlands. This phenomenon is likely exacerbated due to lacking a full-scale understanding of the importance of ponds. In this review, we provided a detailed overview of permanent ponds across Europe, including their usages and the biodiversity they support. By discussing the concepts of pondscape and metacommunity theory, we highlighted the importance of connectivity among and between ponds and identified fluxes of emerging insects as another ES of ponds. Those insects are rich in essential nutrients such as polyunsaturated fatty acids (PUFA), which are delivered through them to the terrestrial environment, however the extent and impact of this ES remains largely unexplored. Several potential stressors, especially related to ongoing global change, which influence pond diversity and integrity were discussed. To conclude this review, we provided our insights on future pond management. Adaptive measures, taking into account the pond system per se within the pondscape, were found to be the most promising to mitigate the loss of natural ponds and restore and conserve natural small water bodies as refuges and diversity hotspots in increasingly urbanized landscapes.

Evaluation of Polycyclic Aromatic Hydrocarbon in water from Dukan lake to main distributer stations in Sulaimani City, Iraq

“…Polycyclic aromatic hydrocarbons (PAH) are xenobiotic compounds composed of carbon and hydrogen. They are a class of nonpolar, hydrophobic pollutants with low water solubility, high melting and boiling points, and low vapor pressure [7] . PAH are typically formed through the incomplete combustion of organic matter, such as fossil fuels and wood.…”

Food web collapse and regime shift following goldfish introduction in permanent ponds

“…Despite their small individual size, permanent ponds (Richardson et al, 2022) represent the most abundant freshwater systems on Earth (Downing et al, 2006) and provide key ecosystem services such as water supply and quality improvement, food provisioning or global biodiversity support (Biggs et al, 2017;Fehlinger et al, 2022).…”

“…They are especially suitable model systems to study the effects of alien predator introduction on complex food webs because they are strongly structured by top-down effects (Carpenter et al, 1985;Jones & Sayer, 2003;Shurin et al, 2002) and alien species introduction is a major issue in these ecosystems (Biggs et al, 2017;Fehlinger et al, 2022). Indeed, pond communities are often very specialized and their structure is heavily dependent upon the equilibrium that exists among competing primary producers (phytoplankton, macrophytes and periphyton), which is stabilized by predator-mediated trophic cascades.…”

“…Despite their small individual size, permanent ponds (Richardson et al., 2022) represent the most abundant freshwater systems on Earth (Downing et al., 2006) and provide key ecosystem services such as water supply and quality improvement, food provisioning or global biodiversity support (Biggs et al., 2017; Fehlinger et al., 2022). They are especially suitable model systems to study the effects of alien predator introduction on complex food webs because they are strongly structured by top‐down effects (Carpenter et al., 1985; Jones & Sayer, 2003; Shurin et al., 2002) and alien species introduction is a major issue in these ecosystems (Biggs et al., 2017; Fehlinger et al., 2022). Indeed, pond communities are often very specialized and their structure is heavily dependent upon the equilibrium that exists among competing primary producers (phytoplankton, macrophytes and periphyton), which is stabilized by predator‐mediated trophic cascades.…”

Functional and temporal facets of predation by marsh frogs across the aquatic–terrestrial ecotone of ponds and implications in the context of biological invasions

“…This is mainly due to the spatially compressed structure of freshwater environments, which may lead to inordinate destabilizing effects of predation by high-rank consumers (McCann, Rasmussen & Umbanhowar, 2005). Because ponds are sensitive biodiversity hotspots of great ecological importance (Dudgeon et al, 2006;Fehlinger et al, 2022;Reid et al, 2019), predation exerted by non-native species raises substantial concern for native aquatic communities. Therefore, some recent research has assessed the impact of invasive semi-aquatic anurans on aquatic communities (Courant et al, 2018b;Bissattini, Buono & Vignoli, 2019;Gobel, Laufer & Cortizas, 2019;Gobel et al, 2022).…”