Eutrophication, a growing environmental concern, exacerbates algal blooms and alters the physical and chemical properties of water, thereby diminishing biodiversity, water quality, and ecosystem services. While various control strategies have been developed, most are designed for temperate regions and may not be applicable to tropical systems, which differ ecologically and climatically. This study reviewed 84 articles published between 2000 and 2024, focusing on eutrophication management in tropical and subtropical lakes. The studies were categorized into physical (8), chemical (17), and biological (59) approaches. Over time, research activity has increased, with Asia leading in publication output. Among biological strategies, biomanipulation—especially the use of macrophytes—emerged as the most common and effective strategy. Macrophytes are preferred due to their strong antagonistic interaction with algae, ease of implementation, cost-effectiveness, and minimal ecological risks. While the review also addresses the limitations of each method, it concludes that macrophyte-based biomanipulation remains a promising tool for mitigating eutrophication in tropical and subtropical freshwater ecosystems. In this context, effective lake restoration requires balancing ecological goals with human needs, supported by stakeholder engagement, community education, and multi-sectoral governance.
Se monitorearon las aguas costeras de 6 playas recreativas en la costa de Campeche en el golfo de México de marzo a octubre de 2019. Los rangos de temperatura, salinidad y pH variaron según la temporada y probablemente estuvieron influenciados por la hidrografía local y la poca profundidad del área de estudio. Los taxones nocivos identificados en este estudio incluyeron 3 especies de diatomeas, 5 dinoflagelados y 2 cianobacterias, con abundancias que oscilaron entre 102 y 105 cél·L–1. Dentro de la comunidad de fitoplancton, los fitoflagelados (nanofitoplancton 20 μm), incluidas diatomeas, dinoflagelados y cianobacterias, fue un componente secundario con densidades que oscilaron entre 103 y 106 cél·L–1. El dinoflagelado Pyrodinium bahamense, identificado como tóxico para los humanos en la costa de Campeche, mostró una abundancia máxima de 2.0 × 105 cel·L–1 en mayo en Boca del Río. La diatomea tóxica Pseudo-nitzschia exhibió una abundancia máxima de 105 cél·L–1 en Payucan en mayo. Los géneros de cianobacterias Anabaena y Trichodesmium exhibieron abundancias que oscilaron entre 102 y 104 cél·L–1. En todas las estaciones y meses se presentaron fitoplancton y cianobacterias potencialmente dañinos, lo que indica que es necesario un monitoreo continuo para evaluar la calidad de las playas y garantizar la seguridad de las playas recreativas.
The unplanned development of a port city generates urban growth in its coastal zone that stresses the local biotic and abiotic resources, affecting the nesting beach areas of sea turtles. This work evaluated the impact of social collaboration on sea turtle conservation in response to coastal rigidization. Over the past twenty years, the Manzanillo Port (Colima), located in the Mexican Central Pacific, underwent vigorous development and urbanization. This growth has produced stressors including increasing levels of marine noise pollution due to the transit of merchant ships, the decrease in 4.3 ha in beach areas, and increased light pollution, which likely reduced the number of turtles that reached the nesting stage. Despite the above, the number of turtle nests has increased thanks to social collaboration through protection actions, education programs, and the participation of volunteers along with public and private organizations supported by the media and social networks. These actions are part of citizen science and contribute to the balance between urban development and the protection of sea turtles, reducing environmental vulnerability in the coastal zone. This success story can be reproduced in coastal cities for other wildlife species to achieve a social-ecological benefit through advocacy projects that involve the empowerment of local inhabitants and the appropriation of their landscapes and natural elements. These projects will contribute to alleviating the effects of coastal rigidization in the face of future challenges that will require solutions to different environmental aspects of imminent climate change.