Can Constructed Wetlands be Wildlife Refuges? A Review of Their Potential Biodiversity Conservation Value

Abstract

The degradation of wetland ecosystems is currently recognized as one of the main threats to global biodiversity. As a means of compensation, constructed wetlands (CWs), which are built to treat agricultural runoff and municipal wastewater, have become important for maintaining biodiversity. Here, we review studies on the relationships between CWs and their associated biodiversity published over the past three decades. In doing so, we provide an overview of how wildlife utilizes CWs, and the effects of biodiversity on pollutant transformation and removal. Beyond their primary aim (to purify various kinds of wastewater), CWs provide sub-optimal habitat for many species and, in turn, their purification function can be strongly influenced by the biodiversity that they support. However, there are some difficulties when using CWs to conserve biodiversity because some key characteristics of these engineered ecosystems vary from natural wetlands, including some fundamental ecological processes. Without proper management intervention, these features of CWs can promote biological invasion, as well as form an ‘ecological trap’ for native species. Management options, such as basin-wide integrative management and building in more natural wetland components, can partially offset these adverse impacts. Overall, the awareness of managers and the public regarding the potential value of CWs in biodiversity conservation remains superficial. More in-depth research, especially on how to balance different stakeholder values between wastewater managers and conservationists, is now required.

Mapping of biodiversity hubs and key ecosystem services as a tool for shaping optimal areas for conservation

“…Rich biodiversity in protected wetlands can improve their treatment efficiency by enhancing their biogeochemical cycling [ 73 ] hence, enormously contributing to boost carbon sequestration hence, the reduction of carbon emissions. By contrast, urban areas are generally characterized by high concentration of nitrate, ammonia, and phosphate levels and are responsible for high concentrations of Ca, alkalinity, and T-hardness in the downstream rural area waters through erosions, surface and subsurface flow, and agricultural runoff.…”

Sıcaklık Değişimlerinin Ostrakod (Crustacea) Türlerinin Mekansal Dağılımı ve Ekolojisi Üzerine Etkisi

“…In conclusion, inland waters, especially the shallow water bodies, are critical for species conservation, biogeochemical cycling, and hydrological management even though they occupy an only a small portion of the Earth (An et al 2013;Zhang et al 2020). However, because of current temperature changes elevated by human activities, ecological features of many aquatic habitats have been changed, causing a critical alteration in species composition and their geographic distribution Finlayson et al 2013).…”

Mean residence time of lagoons in shallow vegetated floodplains

“…As such, they offer low‐cost and low‐maintenance processes of removing wastewater N and P through precipitation into the soil bottom, soil adsorption of chemicals, plant uptake with organic matter accumulation, and microbial immobilization (Margalef‐Martí et al, 2019). In addition, they provide new habitats for aquatic organisms, refuges for wildlife, and can be used as recreational or educational facilities (Zhang et al, 2020). In other words, CW are eco‐friendly water treatment solutions with added ecological values.…”