Effects of Groundwater Inputs to the Hydraulic Circulation, Water Residence Time, and Salinity in a Moroccan Atlantic Lagoon

The finite element model SHYFEM was used to study the hydrodynamics and variability of water level, salinity, temperature, and water residence time (WRT) in the Oualidia lagoon located on the Moroccan Atlantic coast. The lagoon hosts a RAMSAR convention-protected area and also offers a set of valuable ecosystem services providing the source of income for the local population. To assess the effects of submarine groundwater discharge (SGD) inputs in the study area, four simulations were set up using different SGD inputs estimates in addition to tidal forcing, bathymetry, meteorological data including solar radiation, rain, and wind, in addition to boundary conditions in the Atlantic such as salinity, water level, and water temperature. The model was calibrated and validated using hydrodynamic measurements of previous studies in 2012 and 2013. The final results from the model are in good agreement with measured data. The simulation with SGD input ~0.05 m3 s−1 produced salinity values closest to the observed ones. Calculated spatial distribution of WRT, temperature, and salinity reduced to coordinates in two PCA axes is consistent with lagoon zones developed earlier using the benthic macroinvertebrate distribution. The calculated spatial distribution of WRT allowed us to evaluate the placement of oyster aquaculture farms and small-scale fisheries in relation to water quality issues existing in the lagoon.

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Mapping and Assessing Commercial Fisheries Services in the Lithuanian Part of the Curonian Lagoon

Fishes ◽

10.3390/fishes7010019 ◽

2022 ◽

Vol 7 (1) ◽

pp. 19

Author(s):

Edgaras Ivanauskas ◽

Andrius Skersonas ◽

Vaidotas Andrašūnas ◽

Soukaina Elyaagoubi ◽

Artūras Razinkovas-Baziukas

Keyword(s):

Spatial Distribution ◽

Residence Time ◽

Fish Species ◽

Circulation Model ◽

Curonian Lagoon ◽

Water Residence Time ◽

Total Catch ◽

Catch Per Unit Effort ◽

Commercial Fish ◽

The Impact

The spatial distribution of biomass of main commercial fish species was mapped to estimate the supply of a provisioning fishery service in the Curonian lagoon. Catch per unit effort (CPUE) was used as a proxy to estimate the efficiency of commercial fishing and, subsequently, the potential biomass of fishes. The relationship between distinctive characteristics of the fishing areas and corresponding commercial catches and CPUE was analyzed using multivariate analysis. The total catch values and CPUE used in the analyses were derived from the official commercial fishery records. RDE analysis was used to assess the variation of both catch and CPUE of commercial fish species, while the percentages of bottom sediment type coverage, average depth, annual salinity, and water residence time in each of the fishing squares were used as explanatory variables. This distance e-based redundancy analysis allowed for the use of non-Euclidean dissimilarity indices. Fisheries data spatial distribution map indicated the lack of coherence between the spatial patterns of commercial catches and CPUE distribution in the northern part of the lagoon. Highest CPUE values were estimated in the central-eastern part of the lagoon as compared to the western part of the lagoon where CPUE values were substantially lower. Both total catch and CPUE appeared not to be related to the type of bottom habitats statistically while being spatially correlated in-between. However, the impact of salinity and water residence time calculated using the 3D hydraulic circulation model on the distribution of both CPUE and commercial catches was statistically significant.

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Water Residence Time in a Typical Tributary Bay of the Three Gorges Reservoir

Water ◽

10.3390/w11081585 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1585 ◽

Cited By ~ 3

Author(s):

Yao Cheng ◽

Zheng Mu ◽

Haiyan Wang ◽

Fengxia Zhao ◽

Yu Li ◽

...

Keyword(s):

Water Level ◽

Residence Time ◽

Three Gorges Reservoir ◽

Water Exchange ◽

Exchange Capacity ◽

Water Residence Time ◽

Three Gorges ◽

Density Currents ◽

The Three Gorges Reservoir ◽

The Three Gorges

Tributary bays of the Three Gorges Reservoir (TGR) are suffering from environmental problems, e.g., eutrophication and algae bloom, which could be related to the limited water exchange capacity of the tributary bays. To understand and quantify the water exchange capacity of a tributary bay, this study investigated the water residence time (RT) in a typical tributary bay of TGR, i.e., the Zhuyi Bay (ZB), using numerical simulation and the adjoint method to obtain the RT. The results show that RT of ZB with an annual mean of 16.7 days increases from the bay mouth to the bay top where the maximum can reach 50 days. There is a significant seasonal variation in RT, with higher RT (average 20 days) in spring and autumn and lower RT (average < 5 days) in the summer. The sensitivity experiments show that the TGR water level regulation has a strong influence on RT. The increase in the water level could increase RT of ZB to some extent. Density currents induced by the temperature difference between the mainstream and tributaries play an important role in the water exchange of ZB, while the impacts of the river discharges and winds on RT are insignificant.

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Degree-day modelling of the surface mass balance of Urumqi Glacier No. 1, Tian Shan, China

The Cryosphere Discussions ◽

10.5194/tcd-4-207-2010 ◽

2010 ◽

Vol 4 (1) ◽

pp. 207-232 ◽

Cited By ~ 6

Author(s):

E. Huintjes ◽

H. Li ◽

T. Sauter ◽

Z. Li ◽

C. Schneider

Keyword(s):

Spatial Distribution ◽

Mass Balance ◽

Meteorological Data ◽

Model Performance ◽

Western China ◽

Shortwave Radiation ◽

Small Scale ◽

Surface Mass Balance ◽

Surface Mass ◽

Degree Day

Abstract. A distributed temperature-index melt model including potential shortwave radiation is used to calculate annual mean surface mass balance and the spatial distribution of melt rates on the east branch of Urumqi Glacier No. 1, north-western China. The lack of continuous datasets at higher temporal resolution for various climate variables suggests the application of a degree-day model with only few required input variables. The model is calibrated for a six day period in July 2007, for which daily mass balance measurements and meteorological data are available. Based on point measurements of mass balance, parameter values are optimised running a constrained multivariable function using the simplex search method. To evaluate the model performance, annual mass balances for the period 1987/88–2004/05 are calculated using NCEP/NCAR-Reanalysis data. The modelled values fit the observed mass balance with a correlation of 0.98 and an RMSE of 332 mm w.e. Furthermore, the calculated spatial distribution of melt rates shows an improvement in small-scale variations compared to the simple degree-day approach.

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Water Level Control of Small-scale Hydroelectric Power Plant

IEEJ Transactions on Electronics Information and Systems ◽

10.1541/ieejeiss1987.122.6_989 ◽

2002 ◽

Vol 122 (6) ◽

pp. 989-994

Author(s):

Shinichiro Endo ◽

Masami Konishi ◽

Hirosuke Imabayashi ◽

Hayami Sugiyama

Keyword(s):

Power Plant ◽

Water Level ◽

Hydroelectric Power Plant ◽

Small Scale ◽

Hydroelectric Power ◽

Level Control

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Impact of the Small-Scale Spatial Distribution of Dust Particles on the Chemical Evolution of the Diffuse Interstellar Medium

Astronomy Reports ◽

10.1134/s1063772920090061 ◽

2020 ◽

Vol 64 (8) ◽

pp. 693-710

Author(s):

V. A. Sokolova ◽

A. I. Vasyunin ◽

A. B. Ostrovskii ◽

S. Yu. Parfenov

Keyword(s):

Spatial Distribution ◽

Interstellar Medium ◽

Chemical Evolution ◽

Dust Particles ◽

Small Scale

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Small-scale spatial distribution of COVID-19-related excess mortality

MethodsX ◽

10.1016/j.mex.2021.101257 ◽

2021 ◽

Vol 8 ◽

pp. 101257

Author(s):

Dino Gibertoni ◽

Francesco Sanmarchi ◽

Kadjo Yves Cedric Adja ◽

Davide Golinelli ◽

Chiara Reno ◽

...

Keyword(s):

Spatial Distribution ◽

Excess Mortality ◽

Small Scale

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The definition of an atmospheric database for Aeolus

Atmospheric Measurement Techniques ◽

10.5194/amt-4-67-2011 ◽

2011 ◽

Vol 4 (1) ◽

pp. 67-88 ◽

Cited By ~ 5

Author(s):

G. J. Marseille ◽

K. Houchi ◽

J. de Kloe ◽

A. Stoffelen

Keyword(s):

High Resolution ◽

Meteorological Data ◽

Sampling Strategy ◽

Laser Wavelength ◽

Geographic Region ◽

Atmospheric Dynamics ◽

Specific Humidity ◽

Small Scale ◽

Horizontal Line ◽

Definition Of

Abstract. The definition of an atmospheric database is an important component of simulation studies in preparation of future earth observing remote sensing satellites. The Aeolus mission, formerly denoted Atmospheric Dynamics Mission (ADM) or ADM-Aeolus, is scheduled for launch end of 2013 and aims at measuring profiles of single horizontal line-of-sight (HLOS) wind components from the surface up to about 32 km with a global coverage. The vertical profile resolution is limited but may be changed during in-orbit operation. This provides the opportunity of a targeted sampling strategy, e.g., as a function of geographic region. Optimization of the vertical (and horizontal) sampling strategy requires a characterization of the atmosphere optical and dynamical properties, more in particular the distribution of atmospheric particles and their correlation with the atmospheric dynamics. The Aeolus atmospheric database combines meteorological data from the ECMWF model with atmosphere optical properties data from CALIPSO. An inverse algorithm to retrieve high-resolution particle backscatter from the CALIPSO level-1 attenuated backscatter product is presented. Global weather models tend to underestimate atmospheric wind variability. A procedure is described to ensure compatibility of the characteristics of the database winds with those from high-resolution radiosondes. The result is a high-resolution database of zonal, meridional and vertical wind, temperature, specific humidity and particle and molecular backscatter and extinction at 355 nm laser wavelength. This allows the simulation of small-scale atmospheric processes within the Aeolus observation sampling volume and their impact on the quality of the retrieved HLOS wind profiles. The database extends over four months covering all seasons. This allows a statistical evaluation of the mission components under investigation. The database is currently used for the development of the Aeolus wind processing, the definition of wind calibration strategies and the optimization of the Aeolus sampling strategy.

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Local Communities as a Tool for the Development of Municipal Democracy: German Experience and Lessons for Russia

Sravnitel noe konstitucionnoe obozrenie ◽

10.21128/1812-7126-2020-5-74-88 ◽

2020 ◽

Vol 29 (5) ◽

pp. 74-88

Author(s):

Aleksandr Larichev ◽

Emil Markwart

Keyword(s):

Local Government ◽

Urban Areas ◽

Local Population ◽

Local Communities ◽

The State ◽

Household Waste ◽

Small Scale ◽

Issue Management ◽

State Management ◽

Municipal Level

Local government as a political, legal and social institution finds itself in a very difficult period of development in Russia. The long-established tendency of its subordination to the state has intensified today in connection with the newly adopted constitutional amendments. At the same time, it seems obvious that further “embedding” of local government into the state management vertical, in the absence of any positive effect in terms of solving socio-economic and infrastructural problems, will inevitably lead to other hard to reverse, negative results both for local government institutions and the system of public authority as a whole. The normal functioning of local government requires, however, not only the presence of its sufficient institutional and functional autonomy from the state, but also an adequate territorial and social base for its implementation. To ensure the formation of viable territorial collectives, especially in urban areas, it seems appropriate to promote the development of self-government based on local groups at the intra-municipal level. Such local groups can independently manage issues of local importance on a small scale (landscaping, social volunteering, and neighborly mutual assistance), and provide, within the boundaries of a local territory, due civil control over the maintenance by municipal authorities of more complex and large-scale local issues (repair and development of infrastructure, removal of solid household waste and more). At the same time, the development of local communities can by no means be a self-sufficient and substitutional mechanism, whose introduction would end the need for democracy in the full scope of municipal structures overall. In this regard, the experience of local communities’ development in Germany, a state with legal traditions similar to Russian ones, with a centuries-old history of the development of territorial communities and a difficult path to building democracy and forming civil society, seems to be very interesting. Here, the progressive development of local forms of democracy and the participation of residents in local issue management are combined with stable mechanisms of municipal government, and the interaction of municipalities with the state does not torpedo the existing citizen forms of self-government. At the same time, the experience of Germany shows that the decentralization of public issue management which involves the local population can only be effective in a situation where, in addition to maintaining a full-fledged self-government mechanism at the general municipal level, relevant local communities are endowed with real competence and resources to influence local issue decision-making. The role of formalized local communities in urban areas, as the German experience shows, can not only facilitate the decentralization of solving public problems, but can also help in timely elimination of triggers for mobilizing citywide supercollectives with negative agendas. This experience seems useful and applicable in the Russian context.

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An analytical model for the behavior of I-shaped beam to cylindrical column connections at room temperature and high temperatures

Journal of Structural Fire Engineering ◽

10.1108/jsfe-04-2021-0016 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Seied Ahmad Hosseini ◽

Mostafa Zeinoddini

Keyword(s):

Analytical Solution ◽

Elevated Temperatures ◽

Element Model ◽

Small Scale ◽

Offshore Platforms ◽

Rotational Stiffness ◽

Rotation Curves ◽

Content Type ◽

Shaped Beam ◽

Cylindrical Column

PurposeIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, are presented.Design/methodology/approachAn analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections is presented. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors.FindingsIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, is presented. The required yield and plastic moments in this model are provided as an extension to Roark's relationships. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors. A reasonable agreement has been found between the analytical model results and the experimental/numerical modeling results.Originality/valueThis article is extracted from the author’s doctoral thesis, and all its achievements belong to the authors of the article.

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Quantifying recent lake level changes in Patagonia (Argentina and Chile): Back to the future?

10.5194/egusphere-egu21-8467 ◽

2021 ◽

Author(s):

Daniel Ariztegui ◽

Clément Pollier ◽

Andrés Bilmes

Keyword(s):

Water Level ◽

Lake Level ◽

Satellite Images ◽

Meteorological Data ◽

Tierra Del Fuego ◽

Water Level Fluctuations ◽

Lake Levels ◽

The Past ◽

Rainfall Variations ◽

The Impact

Lake levels in hydrologically closed-basins are very sensitive to climatically and/or anthropogenically triggered environmental changes. Their record through time can provide valuable information to forecast changes that can have substantial economical and societal impact.Increasing precipitation in eastern Patagonia (Argentina) have been documented following years with strong El Ni&#241;o (cold) events using historical and meteorological data. Quantifying changes in modern lake levels allow determining the impact of rainfall variations while contributing to anticipate the evolution of lacustrine systems over the next decades with expected fluctuations in ENSO frequencies. Laguna Carrilaufquen Grande is located in the intermontane Maquinchao Basin, Argentina. Its dimension fluctuates greatly, from 20 to 55 km2 water surface area and an average water depth of 3 m. Several well-preserved gravelly beach ridges witness rainfall variations that can be compared to meteorological data and satellite images covering the last ~50 years. Our results show that in 2016 lake level was the lowest of the past 44 years whereas the maximum lake level was recorded in 1985 (+11.8 m above the current lake level) in a position 1.6 km to the east of the present shoreline. A five-years moving average rainfall record of the area was calculated smoothing the extreme annual events and correlated to the determined lake level fluctuations. The annual variation of lake levels was up to 1.2 m (e.g. 2014) whereas decadal variations related to humid-arid periods for the interval 2002 to 2016 were up to 9.4 m. These data are consistent with those from other monitored lakes and, thus, our approach opens up new perspectives to understand the historical water level fluctuations of lakes with non-available monitoring data.&#160;Laguna de los Cisnes in the Chilean section of the island of Tierra del Fuego, is a closed-lake presently divided into two sections of 2.2 and 11.9 km2, respectively. These two water bodies were united in the past forming a single larger lake. The lake level was&#160; ca. 4 m higher than today as shown by clear shorelines and the outcropping of large Ca-rich microbialites. Historical data, aerial photographs and satellite images indicate that the most recent changes in lake level are the result of a massive decrease of water input during the last half of the 20th century triggered by an indiscriminate use of the incoming water for agricultural purposes. The spectacular outcropping of living and fossil microbialites is not only interesting from a scientific point of view but has also initiated the development of the site as a local touristic attraction. However, if the use of the incoming water for agriculture in the catchment remains unregulated the lake water level might drop dangerously and eventually the lake might fully desiccate.These two examples illustrate how recent changes in lake level can be used to anticipate the near future of lakes. They show that ongoing climate changes along with the growing demand of natural resources have already started to impact lacustrine systems and this is likely to increase in the decades to come.

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