Causes and consequences of recent degradation of the Magdalena River basin, Colombia

Abstract

Large tropical rivers provide essential societal benefits, including food production, irrigation, hydropower, transportation, and trade routes. However, these human activities pose unprecedented challenges to the integrity of the river systems, a problem that, in most cases, occurs without fully understanding the natural dynamics of these valuable ecosystems. Here, we synthesize the status of recent and long-term (decades-centuries) anthropogenic impacts occurring in one of the world's hotspots of tropical fish diversity, the Magdalena River, Colombia. Unfortunately, the Magdalena River has attracted little research attention compared to similar tropical rivers. We seek to promote research on the compounding impacts of climate change, river impoundment, alien invasive species, catchment deforestation, and water pollution on the Magdalena and the ecosystem services it provides.

Land use-land cover changes and river basin degradation: A case study of the Densu River in Ghana

“…Large tropical rivers serve as vital conduits for trade, irrigation, transit, electricity, and food production. But because of these human endeavours, the integrity of the river systems is facing never-before-seen difficulties, most of which arise from a lack of knowledge of the natural dynamics of these priceless ecosystems (Jaramillo et al, 2022). The term "river basin degradation" describes the deterioration of an ecosystem's ecological health and functionality.…”

A new species of Schlegelia (Schlegeliaceae) from wet montane forest of Colombia and a key for the species of the genus

“…Additionally, the conservation of these forests is at risk due the continuous deforestation and degradation of the “Serranía de Las Quinchas” and their surrounding areas on middle Magdalena river, and the Virolín Region ( Galindo-T. et al 2003 ) especially in the years during the pre- and post-conflict period (peace agreement was signed in 2017). The expansion of deforestation, degradation and water pollution continues ( Salgado et al 2022 ), with significantly greater agricultural use, pasture, selective logging, illicit crops and mining ( Restrepo et al 2021 ). Although conservation status assessments can be made for species with such small numbers of collections ( Rivers et al 2011 ), it may be difficult to assess whether the appearance of rarity in a species is due to the lack of, or outdated, data, or to its actual rarity ( Verspagen and Erkens 2022 ).…”

Two new species of Caryodaphnopsis (Lauraceae) from the Magdalena Medio, Colombia, with an updated key for the Neotropical Caryodaphnopsis species

“…However, more than 80% of its forests has been destroyed (Franco and Rodríguez, 2005;Etter and Rodríguez, 2008;Restrepo et al, 2016). The ex-pansion of deforestation, degradation and water pollution continues (Salgado et al, 2022), with significantly greater agricultural use, pasture, selective logging, illicit crops and mining (Restrepo et al, 2021).…”