Agricultural intensification and drought frequency increases may have landscape‐level consequences for ephemeral ecosystems

Abstract

Ephemeral wetlands in arid regions are often degraded or destroyed through poor land-use practice long before they are ever studied or prioritized for conservation. Climate change will likely also have implications for these ecosystems given forecast changes in rainfall patterns in many arid environments. Here, we present a conceptual diagram showing typical and modified ephemeral wetlands in agricultural landscapes and how modification impacts on species diversity and composition.

Combined impacts of warming and salinisation on trophic interactions and mortality of a specialist ephemeral wetland predator

“…Wetlands are highly biodiverse and productive ecosystems, yet are under increasing pressure from global environmental change via multiple stressors that often act synergistically (Dalu, Wasserman, & Dalu, ; Mabidi, Bird, & Perissinotto, ; White, Donohue, Emmerson, & O'Connor, ). From a biodiversity perspective, ephemeral wetlands are especially important habitats, characteristically inhabited by a rich array of specialists adapted to transient hydroperiods and that may be unable to persist in permanent aquatic ecosystems (Dalu, Wasserman, & Dalu, ; Wasserman, Alexander, Barrios‐O'Neill, Weyl, & Dalu, ). Ephemeral wetlands often provide aquatic habitats for threatened, rare and/or endemic species which are reliant on transient habitat patches within terrestrial environments (Bird et al.,; De Meester et al., ).…”

“…However, despite their significance for regional and global biodiversity, ephemeral wetlands have received relatively little attention due to spatial and temporal heterogeneity, which makes them difficult to detect and conserve during dry periods. The integrity of ephemeral wetlands is thus threatened in multiple ways, such as through land use changes driven by agricultural activity (Brock, Smith, & Jarman, ; Marty, ), species introductions (Cuthbert, Dalu, Wasserman, Dick, et al., ; Dalu, Wasserman, & Dalu, ), and climate change (Lu et al., ). Warming and salinisation are amongst the most pervasive stressors in ephemeral wetlands associated with ongoing environmental change (Dalu, Wasserman, & Dalu, ; Mabidi et al., ).…”

“…The integrity of ephemeral wetlands is thus threatened in multiple ways, such as through land use changes driven by agricultural activity (Brock, Smith, & Jarman, ; Marty, ), species introductions (Cuthbert, Dalu, Wasserman, Dick, et al., ; Dalu, Wasserman, & Dalu, ), and climate change (Lu et al., ). Warming and salinisation are amongst the most pervasive stressors in ephemeral wetlands associated with ongoing environmental change (Dalu, Wasserman, & Dalu, ; Mabidi et al., ). Quantifying the ecological implications of these stressors is key to holistically understanding impacts arising from anthropogenic activity on the functioning and stability of these widespread aquatic habitats.…”

Fish communities in small subtropical reservoirs subject to extensive drawdowns, with focus on the biology of Enteromius paludinosus (Peters, 1852) and Clarias gariepinus (Burchell, 1822)

“…Southern Africa is characterised by large variations in annual rainfall, very few perennial rivers and lacks natural lakes with the exception of a few temporary wetlands and coastal lakes (Ersal 1994;Haas et al 2009;Marshall 2011). This has necessitated for the construction of reservoirs across many rivers and temporal wetlands to ensure adequate water supply (Dalu et al 2017). Zimbabwe has a particularly large number of small reservoirs estimated at 14000 (including unlisted dams), contributing to about 86% of the number of small reservoirs in Southern Africa excluding South Africa (Ersal 1994;Marshall 2011).…”

Impact of Tea Processing Water Wastes on Phytoplankton Composition of Tshinane River, Limpopo Province

“…Aquatic ecosystems in rural South Africa have been impacted over many years by both commercial and subsistence anthropogenic activities [5]. These impacts consist of subsistence and commercial farming, natural pollution and domestic use (washing clothes, cars, washing dishes and for bathing) and recreational use such as swimming.…”