Temporal changes in nutrients in a deep oligomictic lake: the role of external loads versus climate change
Accepted: 15 November 2021
Supplementary: 64
HTML: 57
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.
Authors
The impact of climate change on stratification and mixing patterns has important effects on nutrient availability and plankton dynamics in deep lakes. We demonstrate this in a long-term study of Lake Maggiore, a deep oligomictic lake located in the subalpine lake district in Northern Italy. Studies on physical, chemical and biological features of the lake have been performed continuously since the 1980s. The lake recovered from eutrophication in response to a reduction of catchment nutrient loads and reached a stable oligotrophic status by the end of the 1990s, with average total phosphorus concentrations in the water column around 10 µg L-1. However, both reactive and total phosphorus have slightly increased since 2010, leading to a shift in the lake trophic state towards mesotrophy. The increase in phosphorus has been limited to the hypolimnetic layers, concentrations being fairly stable or decreasing in the epilimnion. Reactive silica also progressively increased in the hypolimnion, while nitrate and total nitrogen concentrations have steadily decreased in both deep and surface layers, especially in the summer period. These changes were assessed in relation to catchment loads, atmospheric deposition and climate-related variations in stratification and mixing patterns and in nutrient retention. Long-term changes in primary production, represented by chlorophyll levels, and biovolume of the main algal groups were also considered. During the eutrophication period and until the 1990s, in-lake phosphorus concentrations were tightly related to external loads; successively, phosphorus and its vertical distribution up the water column became more controlled by internal processes, in particular by stratification and mixing regime. An increase of thermal stability and a reduced frequency and intensity of deep mixing events has fostered oxygen depletion and phosphorus and silica accumulation in the hypolimnion. Another consequence of reduced deep mixing events, has been a reduction in nutrient replenishment of the upper layers at spring mixing. External loads are still the main driver of change for nitrogen compounds: the decrease in the atmospheric load of nitrogen that occurred in the Lake Maggiore area over the last decade, as an effect of reduced nitrogen emissions, has caused decreasing concentration of inorganic nitrogen in the lake. However, the phytoplankton community changes observed might also play a role in nitrogen dynamics, particularly in the nitrate minima observed during summer in recent years.
How to Cite
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Similar Articles
- Michela ROGORA, Letizia GARIBALDI, Giuseppe MORABITO, Silvia ARISCI, Rosario MOSELLO, Present trophic level of Lake Alserio (Northern Italy) and prospect for its recovery , Journal of Limnology: Vol. 61 No. 1 (2002)
- Cuilin Hu, Shengrui Wang, Longgen Guo, Ping Xie, Effects of the proximal factors on the diel vertical migration of zooplankton in a plateau meso-eutrophic Lake Erhai, China , Journal of Limnology: Vol. 73 No. 2 (2014)
- Sameer M. Padhye, Henri J. Dumont, Species richness of Cladocera (Crustacea: Branchiopoda) in the Western Ghats of Maharashtra and Goa (India), with biogeographical comments , Journal of Limnology: Vol. 74 No. 1 (2015)
- Bogdan Gadek, Mirosław Szumny, Bartłomiej Szypuła, Classification of the Tatra Mountain lakes in terms of the duration of their ice cover (Poland and Slovakia) , Journal of Limnology: Vol. 79 No. 1 (2020)
- Alessandro LUDOVISI, Elda GAINO, Meteorological and water quality changes in Lake Trasimeno (Umbria, Italy) during the last fifty years , Journal of Limnology: Vol. 69 No. 1 (2010)
- Angela Boggero, Diego Fontaneto, Giuseppe Morabito, Pietro Volta, Limnology in the 21st century: the importance of freshwater ecosystems as model systems in ecology and evolution , Journal of Limnology: Vol. 73 No. s1 (2014): Limnology in the 21st Century: celebrating 75 years of ecological research in Pallanza
- Joanna Cieślewicz, Mirosław Kobierski, Marcin Cichosz, Geochemical assessment of lake sediments in protected areas in Poland – a search for reference condition , Journal of Limnology: Vol. 77 No. 1 (2018)
- Joaquín Hortal, João C. Nabout, Joaquín Calatayud, Fernanda M. Carneiro, André Padial, Ana M. C. Santos, Tadeu Siqueira, Folmer Bokma, L. Mauricio Bini, Marc Ventura, Perspectives on the use of lakes and ponds as model systems for macroecological research , Journal of Limnology: Vol. 73 No. s1 (2014): Limnology in the 21st Century: celebrating 75 years of ecological research in Pallanza
- Reinhard GERECKE, Marco CANTONATI, Daniel SPITALE, Elisabeth STUR, Sofia WIEDENBRUG, The challenges of long-term ecological research in springs in the northern and southern Alps: indicator groups, habitat diversity, and medium-term change , Journal of Limnology: Vol. 70 No. s1 (2011): Springs: neglected key habitats for biodiversity conservation
- Robert J. Morley, Harsanti P. Morley, Mid Cenozoic freshwater wetlands of the Sunda region , Journal of Limnology: Vol. 72 No. s2 (2013): Freshwater Invertebrates of Southeast Asia
<< < 43 44 45 46 47 48 49 50 51 52 > >>
You may also start an advanced similarity search for this article.
-
Claudia Dresti, Michela Rogora, Andrea FenocchiAquatic Sciences : 2023
-
Simona Musazzi, Martina Austoni, Aldo MarchettoJournal of Limnology : 2023
-
Angela Boggero, Lyudmila Kamburska, Silvia Zaupa, Marzia Ciampittiello, Daniele Paganelli, Marco Cifoni, Michela Rogora, Tiziana Di LorenzoJournal of Limnology : 2022
-
Rossana Caroni, Roberta Piscia, Gary Free, Marina MancaWater : 2023
-
Claudia Dresti, Michela Rogora, Fabio Buzzi, Andrea Beghi, Daniele Magni, Alessandro Canziani, Andrea FenocchiJournal of Environmental Management : 2023
-
Periyasamy Sivalingam, Raffaella Sabatino, Tomasa Sbaffi, Gianluca Corno, Diego Fontaneto, Giulia Borgomaneiro, Michela Rogora, Elena Crotti, Francesca Mapelli, Sara Borin, Andrea Lopez Pilar, Ester M. Eckert, Andrea Di CesareJournal of Hazardous Materials : 2024
-
Cristian Scapozza, Nicola PatocchiJournal of Limnology : 2023
-
Konstantinos Stefanidis, George Varlas, George Papaioannou, Anastasios Papadopoulos, Elias DimitriouScience of The Total Environment : 2023
-
Zooplankton taxa repository of DDTtot and sumPCB14: Seasonal and decadal variations in Lake MaggioreRoberta Piscia, Marina Manca, Rossana Caroni, Piero Guilizzoni, Roberta BettinettiScience of The Total Environment : 2024
-
Cristiana Callieri, Raffaella Sabatino, Andrea Di Cesare, Roberto BertoniAdvances in Oceanography and Limnology : 2023
-
Lyudmila Kamburska, Silvia Zaupa, Angela BoggeroWater : 2023
-
Michela Rogora, Tommaso Cancellario, Rossana Caroni, Lyudmila Kamburska, Dario Manca, Simona Musazzi, Rocco Tiberti, Andrea LamiFrontiers in Environmental Science : 2023
-
Elisabetta Canuti, Martina AustoniMicroorganisms : 2024