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Restored and artificial wetlands do not support the same waterbird functional diversity as natural wetlands

The restoration of degraded areas and the creation of artificial ecosystems have partially compensated for the continuing loss of natural wetlands. However, the success of these wetlands in terms of the capacity of supporting biodiversity and ecosystem functions is unclear. Natural, restored, and artificially created wetlands present within the Doñana protected area were compared to evaluate if they are equivalent in terms of waterbird functional trait diversity and composition. Functional diversity measures and functional group species richness describing species diet, body mass, and foraging techniques were modelled in 20 wetlands in wintering and breeding seasons. Artificial wetlands constructed for conservation failed to reach the functional diversity of natural and restored wetlands. Unexpectedly, artificial ponds constructed for fish production performed better, and even exceeded natural wetlands for functional richness during winter. Fish ponds stood out as having a unique functional composition, connected with an increase in richness of opportunistic gulls and a decrease in species sensitive to high salinity. Overall, the functional structure of breeding communities was more affected by wetland type than wintering communities. These findings suggest that compensating the loss of natural wetlands with restored and artificial wetlands results in systems with altered waterbird?supported functions. Protection of natural Mediterranean wetlands is vital to maintain the original diversity and composition of waterbird functional traits. Furthermore, restoration must be prioritised over the creation of artificial wetlands, which, even when intended for conservation, may not provide an adequate replacement. informacion[at] Almeida et al. (2020) Comparing the diversity and composition of waterbird functional traits between natural, restored, and artificial wetlands. Freshwater Biology DOI 10.1111/fwb.13618
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Determination of anthropogenic contamination in surface waters using helophytes

Determination of anthropogenic contamination in surface waters using helophytes

Nitrogen (N) loading from anthropogenic activities is contributing to the eutrophication and degradation of wetlands worldwide. Doñana (southwestern Spain), includes a dynamic marshland protected as a UNESCO World Heritage Site, which has a catchment area exposed to increasing N inputs from intensive agriculture and poorly treated urban wastewaters. Identifying the sources of N entering this iconic wetland complex is vital for its conservation. To this end, multiyear (2014–2016), spatially-explicit data on N concentration in water samples were combined with measurements on the relative abundance of N stable isotopes (d15N) in Bolboschoenus maritimus and Typha domingensis, two dominant helophytes (i.e. emergent macrophytes) in the Doñana marsh and entry streams. Overall, plant tissues from entry streams showed higher d15N values than those from the marsh, particularly in those streams most affected by urban wastewaters. Isotopic values did not differ between plant species. Water samples affected by isotopically-enriched urban wastewaters and other diffuse organic N inputs (e.g. livestock farming) had relatively high Dissolved Inorganic Nitrogen (DIN) concentrations. In contrast, in streams mainly affected by diffuse N pollution from greenhouse crops, high DIN values were related to isotopically-depleted N sources (e.g., inorganic fertilizers). Thus, helophytes, in combination with other parameters such as N concentration in water or land cover, can be valuable indicators of anthropogenic pressures in Mediterranean wetlands. Helophytes have widespread distributions, and can be readily sampled even when water is no longer present. However, identification of specific N sources through helophyte d15N values is limited when key potential N sources are isotopically undistinguishable (e.g. fertilizers vs. atmospheric sources). informacion[at] Paredes et al (2019) Stable isotopes in helophytes reflect anthropogenic nitrogen pollution in entry streams at the Doñana World Heritage Site. Ecol Indicators 97: 130-140. Doi 10.1016/j.ecolind.2018.10.0009