Abandon mined land: allow freshwater marshes or swamps to recover without active intervention
Overall effectiveness category No evidence found (no assessment)
Number of studies: 0
Background information and definitions
It may be possible that marshes or swamps will recover on their own, without any active intervention, if human activities are stopped. Such passive recovery can be cheaper than active intervention and allow development of a community well adapted to local conditions. However, plant colonization may not occur at all or, if it does, occur slowly or be dominated by invasive species (Zahawi et al. 2014). Successful recovery may be hindered by physical degradation (e.g. a water table that is too low, restricted tidal exchange, compacted sediment), chemical degradation (e.g. acidified soils or presence of heavy metals) or an insufficient supply of propagules.
To be summarized as evidence for this action, studies must have monitored historically mined land that has been abandoned (mining activities completely stopped, with no additional intervention) with the expectation that marshes or swamps could recover (i.e. excluding studies of abandoned upland mines). Therefore, the summarized evidence is best considered as an indication of what kind of vegetation can develop in historically mined areas, and how long it takes to develop, rather than a complete survey of all relevant evidence.
Zahawi R.A., Reid J.L. & Holl K.D. (2014) Hidden costs of passive restoration. Restoration Ecology, 22, 284–287.