Application of the Lake Biotic Index (LBI) in the ecological characterization of a North Patagonian lake in Chile

New records of the Endangered southern river otter Lontra provocax, with notes on its diet, in threatened wetlands of southern Chile

The wetlands inhabited by the southern river otter Lontra provocax in Chile are subject to anthropogenic disturbances. As a result of the modification and destruction of its habitat, caused by loss of riparian vegetation, and other threats, the species is categorized as Endangered on the IUCN Red List. We monitored the river otter and its diet during September 2020–January 2021 in a swamp forest fragment in southern Chile. We obtained evidence of river otter presence from the upper part of the wetland to the confluence with the Bueno River, suggesting inter-population connectivity of the species in an extensive hydrographic basin. Faeces and food remains showed a predominance of native macrocrustaceans, with introduced fish present at lower levels. The detection of the southern river otter in a fragment of threatened swamp forest suggests a low abundance in environmentally degraded freshwater environments. The identification of subpopulations such as the one reported here provides valuable data to support the conservation of the species in threatened wetlands.

Eco-bioengineering tools in ecohydrological assessment of eutrophic water bodies

Eutrophication of water bodies and deterioration of water quality are emerging environmental crises. The root causes and consequences of eutrophication are multidirectional. Thus, they provide a huge scope of risk-analysis and risk-assessment in the domain of remediation studies. However, recent restoration studies reveal a global trend of utilizing traditional restoration methods combined with advanced pioneer innovative techniques developed in the field of science and technology. This review introduces a novel approach to consider ecohydrological assessment of eutrophication by classical biomanipulation practices emphasising on their evolution into innovative 'eco-bioengineering' methods. The main objective of this study is to critically analyse and recognize the research gaps in classical biomanipulation and appreciate the reproducibility and efficacy of eco-bioengineering methods at micro- and macrolevel aquatic ecosystems. Comprehensive literature review was conducted on offline and online platforms. Our survey revealed (a) continuation of a historical trend in classical biomanipulation practices (61.64%) and (b) an ascending drift in eco-bioengineering research (38.36%) in the last decade (2010-2021). At a global scale, recent biomanipulation research has a skewed distribution in Europe (41.10%), East Asia (32.88%), North America (10.96%), South Africa (4.11%), South America (2.74%), Middle East (1.37%), Oceania (1.37%), and non-specific regions (5.48%). Finally, this review analysis revealed the comprehensiveness of eco-bioengineering methods and their strong ecological resilience to recurrence of eutrophication and fluctuating environmental flows in the future. Therefore, our review reinforces the supremacy of eco-bioengineering methods as cost-effective green technologies providing sustainable solutions to restore the eutrophic waters at a global scale.