To What Extent Can Constructed Wetlands Enhance Biodiversity?

Abstract

Abstract-We carried out a literature review to find evidence from empirical studies that constructed wetlands (CWs) can increase biodiversity at the site or landscape level. A set of criteria from general and theoretical ecology was developed that we found useful for defining 'best practice' in the construction of wetlands (e.g. landscape connectivity, area versus size, disturbance regime). Thereafter, we analyzed 21 original research papers where biodiversity development after wetland construction was documented. Wetland construction is a established routine procedure serving various purposes in environmental protection, such as waste water retention and treatment. 'Best practice' criteria with respect to biodiversity protection were not regularly applied during the construction and monitoring process. The published records were substantially different as far as methodological approaches and aims are concerned. They contained short-term snapshot studies to long-term monitoring of biotic and abiotic conditions. Only a few case studies were published in international journals where biodiversity improvement in terms of specific biodiversity indicators was well-documented. A general conclusion whether or not biodiversity is enhanced by CWs cannot be drawn from the published record. As there are confirming results in some studies, we conclude that under certain circumstances constructed wetlands can be useful complements to other biodiversity conservation strategies.

Nature based measures increase freshwater biodiversity in agricultural catchments

“…There is often an assumption that nature based measures will be 'good for wildlife', and that ecosystem services features, such as SUDs waterbodies, agricultural bunded ditches and interception ponds will inevitably provide multi-functional benefits that include biodiversity gain (Burgess-Gamble et al, 2017). In practice, studies to test these assumptions have shown mixed results depending on the type of measures introduced and the biotic group used to derive metrics (Hansson et al, 2005;Thiere et al, 2009;Wiegleb et al, 2017). The results from our plant-based study provides some support for the value of ecosystem services waterbodies, particularly for reversing the impact of short term losses in catchment plant richness, and increasing the number of populations of some unique and replicate species.…”

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

“…The value of long-term observation and comparative studies on the multiple ecological functions of CWs and natural wetlands cannot be underestimated, especially given that vegetation succession in CWs and the associated faunal turnover can be rapid. Indeed, the temporal dynamics of biological communities in CWs can have complicated implications for both pollutant removal and biodiversity conservation [153,154].…”

Successional changes in plant composition over 15 years in a created wetland in South Korea

“…The portion of wetland plants was reduced over time, but~56% remained in 2013, demonstrating that the created wetland performed the function of habitats for wetland plants (Table 1). Under proper maintenance of water depth, created wetlands can greatly enhance biodiversity (Wiegleb et al 2017).…”