Trends and relations among basic phytoplankton characteristics in the course of the long-term oligotrophication of Lake Maggiore (Italy)

1998 ◽  
pp. 243-257 ◽  
Author(s):  
D. Ruggiu ◽  
G. Morabito ◽  
P. Panzani ◽  
A. Pugnetti
Keyword(s):  
Lake Maggiore

Lake Maggiore (N. Italy) trophic history: fossil diatom, plant pigments, and chironomids, and comparison with long-term limnological data

2004 ◽  
Vol 113 (1) ◽  
pp. 97-110 ◽  
Author(s):  
Aldo Marchetto ◽  
Andrea Lami ◽  
Simona Musazzi ◽  
Julieta Massaferro ◽  
Leonardo Langone ◽  
...  
Keyword(s):  
Plant Pigments ◽  
Lake Maggiore

scholarly journals Strategic decision making under climate change: a case study on Lake Maggiore water system

2014 ◽  
Vol 364 ◽  
pp. 532-537
Author(s):  
M. Micotti ◽  
R. Soncini Sessa ◽  
E. Weber
Keyword(s):  
Climate Change ◽  
Water Resource Management ◽  
Water System ◽  
Climate Scenario ◽  
Strategic Decision ◽  
Long Term Effects ◽  
Lake Maggiore ◽  
Planning Processes

Abstract. Water resources planning processes involve different kinds of decisions that are generally evaluated under a stationary climate scenario assumption. In general, the possible combinations of interventions are mutually compared as single alternatives. However, the ongoing climate change requires us to reconsider this approach. Indeed, what have to be compared are not individual alternatives, but families of alternatives, characterized by the same structural decisions, i.e. by actions that have long-term effects and entail irrevocable changes in the system. The rationale is that the structural actions, once they have been implemented, cannot be easily modified, while the management decisions can be adapted to the evolving conditions. This paper considers this methodological problem in a real case study, in which a strategic decision has to be taken: a new barrage was proposed to regulate Lake Maggiore outflow, but, alternatively, either the present barrage can be maintained with its present regulation norms or with a new one. The problem was dealt with by multi-criteria decision analysis involving many stakeholders and two decision-makers. An exhaustive set of indicators was defined in the participatory process, conducted under the integrated water resource management paradigm, and many efficient (in Pareto sense) regulation policies were identified. The paper explores different formulations of a global index to evaluate and compare the effectiveness of the classes of alternatives under both stationary and changing hydrological scenarios in order to assess their adaptability to the ongoing climate change.

Endogenous origin of foams in lakes: a long-term analysis for Lake Maggiore (northern Italy)

Hydrobiologia ◽  
2015 ◽  
Vol 767 (1) ◽  
pp. 249-265 ◽  
Author(s):  
F. Stefani ◽  
F. Salerno ◽  
D. Copetti ◽  
D. Rabuffetti ◽  
L. Guidetti ◽  
...  
Keyword(s):  
Northern Italy ◽  
Lake Maggiore ◽  
Term Analysis

scholarly journals A model approach to assess the long-term trends of indirect photochemistry in lake water. The case of Lake Maggiore (NW Italy)

2011 ◽  
Vol 409 (18) ◽  
pp. 3463-3471 ◽  
Author(s):  
Marco Minella ◽  
Michela Rogora ◽  
Davide Vione ◽  
Valter Maurino ◽  
Claudio Minero
Keyword(s):  
Lake Water ◽  
Lake Maggiore ◽  
Long Term Trends ◽  
Nw Italy ◽  
Model Approach

scholarly journals Long-Term Changes in the Zooplankton Community of Lake Maggiore in Response to Multiple Stressors: A Functional Principal Components Analysis

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 962 ◽  
Author(s):  
Andrea Arfè ◽  
Piero Quatto ◽  
Antonella Zambon ◽  
Hugh J. MacIsaac ◽  
Marina Manca
Keyword(s):  
Chlorophyll A ◽  
Principal Components ◽  
Multiple Stressors ◽  
General Tendency ◽  
Bythotrephes Longimanus ◽  
Lake Maggiore ◽  
Biological Variables ◽  
Zooplankton Structure ◽  
Functional Principal Components

We describe the long-term (1981–2008) dynamics of several physico-chemical and biological variables and how their changes may have influenced zooplankton structure in Lake Maggiore (Italy). Data was available for the 1981–1992 and 1995–2008 periods. Standardized time-series for temperature and total phosphorus (TP), chlorophyll-a, phytoplankton density (cel m−3), and cell size (µm3), as well as zooplankton structure (Copepoda, Cladocera, and Rotifera density, ind m−3) were smoothed using penalized B-splines and analyzed using Functional Principal Components (FPCs) to assess their dominant modes of variation. The first four FPCs explained 55% of 1981–1992 and 65% of 1995–2008 overall variation. Results showed that temperature fluctuated during the study period, particularly during 1988–1992 with a general tendency to increase. TP showed a declining trend with some reversions in the pattern observed in the years 1992, 1999, and 2000. Phytoplankton estimators and chlorophyll-a concentration showed a variable trend along the study period. Zooplankton groups also had a variable trend along the study period with a general increase in density of large carnivorous (mainly Bythotrephes longimanus) and a decrease of large herbivorous (mainly Daphnia), and a similar increase in the ratio of raptorial to microphagous rotifers. Our results suggest that the lake experienced a strong trophic change associated with oligotrophication, followed by pronounced climate-induced changes during the latter period. TP concentration was strongly associated with changes in abundance of some zooplankton taxa.

scholarly journals Temporal changes in nutrients in a deep oligomictic lake: the role of external loads versus internal processes

2021 ◽  
Vol 80 (3) ◽  
Author(s):  
Michela Rogora ◽  
Martina Austoni ◽  
Rossana Caroni ◽  
Paola Giacomotti ◽  
Lyudmila Kamburska ◽  
...  
Keyword(s):  
Water Column ◽  
Total Phosphorus ◽  
Inorganic Nitrogen ◽  
Lake Maggiore ◽  
Deep Mixing ◽  
Long Term Study ◽  
Mixing Patterns ◽  
The Impact ◽  
External Loads

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.

Therapy and prevention for mental health: What if mental diseases are mostly not brain disorders?

2019 ◽  
Vol 42 ◽  
Author(s):  
John P. A. Ioannidis
Keyword(s):  
Mental Health ◽  
Mental Disease ◽  
Brain Disorders ◽  
Social Stressors ◽  
Labor Education ◽  
Mental Diseases ◽  
Long Term Follow Up ◽  
Political Decisions

AbstractNeurobiology-based interventions for mental diseases and searches for useful biomarkers of treatment response have largely failed. Clinical trials should assess interventions related to environmental and social stressors, with long-term follow-up; social rather than biological endpoints; personalized outcomes; and suitable cluster, adaptive, and n-of-1 designs. Labor, education, financial, and other social/political decisions should be evaluated for their impacts on mental disease.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

Brief summary of Kleť photographic search programme for minor planets

1999 ◽  
Vol 173 ◽  
pp. 189-192
Author(s):  
J. Tichá ◽  
M. Tichý ◽  
Z. Moravec
Keyword(s):  
Ccd Camera ◽  
Minor Planet ◽  
Minor Planets ◽  
Main Belt

AbstractA long-term photographic search programme for minor planets was begun at the Kleť Observatory at the end of seventies using a 0.63-m Maksutov telescope, but with insufficient respect for long-arc follow-up astrometry. More than two thousand provisional designations were given to new Kleť discoveries. Since 1993 targeted follow-up astrometry of Kleť candidates has been performed with a 0.57-m reflector equipped with a CCD camera, and reliable orbits for many previous Kleť discoveries have been determined. The photographic programme results in more than 350 numbered minor planets credited to Kleť, one of the world's most prolific discovery sites. Nearly 50 per cent of them were numbered as a consequence of CCD follow-up observations since 1994.This brief summary describes the results of this Kleť photographic minor planet survey between 1977 and 1996. The majority of the Kleť photographic discoveries are main belt asteroids, but two Amor type asteroids and one Trojan have been found.

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