Eutrophication, Research and Management History of the Shallow Ypacaraí Lake (Paraguay)

Abstract

Ypacaraí Lake is the most renowned lake in landlocked Paraguay and a major source of drinking and irrigation water for neighbouring towns. Beyond its socioeconomic and cultural significance, it has great ecological importance, supporting a rich biodiversity. Rapid growth of human presence and activities within its basin has led to its environmental degradation, a heartfelt matter of high political concern that compels intervention. Here, by reconstructing the history of scientific and management-oriented research on this system, we provide a comprehensive assessment of current knowledge and practice to which we contribute our recent, novel findings. An upward trend in total phosphorus concentration confirms ongoing eutrophication of an already eutrophic system, evidenced by consistently high values of trophic state indices. Downward trends in water transparency and chlorophyll-a concentration support the hypothesis that primary production in this lake is fundamentally light limited. Statistical and other analyses suggest high sensitivity of the system to hydraulic, hydro-morphological and hydro-meteorological alterations arising, respectively, from engineering interventions, land use and climate change. By discussing knowledge gaps, opportunities for research and challenges for management and restoration, we argue that this case

Characterization of microbial communities associated with cyanoalgal bloom in a dam from León, Gto. México by sequencing of variable regions of the rRNA genes16S and 18S

“…4); la abundancia de Copepoda ha sido asociada con la presencia de nitrógeno amoniacal y fosfatos, mientras que la dominancia de Cyclopoides, como Mesocyclops leukarti, se asocia con fosfatos (Krupa et al, 2020). Phyllopoda (Diplostraca), Copepoda y Calanoida están entre los grupos de zooplancton encontrados en lagos; entre sus funciones ecológicas esta regular la presencia de cianobacterias nocivas (López-Moreira et al, 2018;Ger et al, 2016;Napiórkowska-Krzebietke et al, 2020). Estos A nivel de género y especie, el análisis por cuantiles reveló que a dos metros de profundidad (B2) el género Flavobacterium spp.se presentó en mayor abundancia, comparado con la superficie (Tabla 2 y Fig.…”

A Comparison of Local Path Planning Techniques of Autonomous Surface Vehicles for Monitoring Applications: The Ypacarai Lake Case-study

“…Figure 1 shows a satellite image from Ypacarai Lake taken in the end of 2018. It is a shallow lake with an average depth of 1.72 m and a maximum depth of 2.53 m [29]. There is a large amount of population living in the surroundings whose activities have a direct impact on the conditions of the lake.…”

SMART Research: Toward Interdisciplinary River Science in Europe

“…Six SMART EMJD doctoral candidates further analyzed data from one or more rivers using existing national or international databases and GIS analysis in Europe. Three doctoral candidates studied and used existing data of rivers or other freshwater systems in Africa and South America (Monegaglia et al, 2018), New Zealand (Redolfi et al, 2016), and Paraguay (López Moreira M et al, 2018). Finally, 4 doctoral candidates compiled existing data sets for global-scale studies (e.g., He et al, 2019;Shumilova et al, 2019).…”