Resolution of the spatial variability in sediment composition within and between water-storage reservoirs using non-parametric statistical techniques

Reasons why water storage reservoirs are necessary in accordance with the sustainable development strategy are described in the paper. The main positive and negative impacts of reservoirs on the environment are analyzed. The most important are: the improvement of hydrological regimes (decreasing maximal and increasing minimal flows), the creation of optimal water management, utilization and protection of water, and the creation of better conditions for river and coastal ecosystems. Negative impacts and measures for its mitigation or elimination are also analyzed. The conclusion is that water storage reservoirs can be harmoniously incorporated into the environment. Serbia has a limited number of locations suitable for the construction of reservoirs, therefore it is necessary to retain these areas for storage in regional development plans and other legal acts.

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Spatial variability in sediment composition and evidence for resuspension in a large, deep lake

Marine and Freshwater Research ◽

10.1071/mf9950321 ◽

1995 ◽

Vol 46 (1) ◽

pp. 321 ◽

Cited By ~ 8

Author(s):

ME Lebo ◽

JE Reuter

Keyword(s):

Spatial Variability ◽

Sediment Trap ◽

Particle Flux ◽

Accumulation Rate ◽

Sediment Accumulation ◽

Sediment Composition ◽

Deep Lake ◽

Organic C ◽

Pyramid Lake ◽

Organic Fractions

Spatial variability in the composition of sediments in Pyramid Lake, Nevada, was assessed in June 1992 by collecting surficial samples at 32 sites. For those sites, organic fractions were highest in the centre of the lake and low near the single inflow to the system. The spatial patterns for organic C, N, and P in lake sediments indicated that small organic-rich particles are preferentially deposited in the centre of the lake. This sorting of particles by water depth was supported by a corresponding decrease in the particle size distribution of sediments with station depth and by limited sediment-trap data. Further, a comparison of sediment-trap particle flux rates with the net sediment accumulation rate for the centre of the lake based on 210Pb decay indicated that the resuspension of bottom sediments in Pyramid Lake (zmax = 102 m) must occur throughout the lake.

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The spatial variability of soil water storage and its controlling factors during dry and wet periods on loess hillslopes

CATENA ◽

10.1016/j.catena.2017.10.029 ◽

2018 ◽

Vol 162 ◽

pp. 333-344 ◽

Cited By ~ 7

Author(s):

Xuemei Mei ◽

Qingke Zhu ◽

Lan Ma ◽

Dong Zhang ◽

Huifang Liu ◽

...

Keyword(s):

Spatial Variability ◽

Soil Water ◽

Water Storage ◽

Controlling Factors ◽

Soil Water Storage

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Perception, Motivation, and Satisfaction of Female Tourists with Their Visit to the City of Cordoba (Spain)

Sustainability ◽

10.3390/su12187595 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7595

Author(s):

Alexandra Lenis Escobar ◽

Ramón Rueda López ◽

Manuel Pérez-Priego ◽

María de los Baños García-Moreno García

Keyword(s):

Statistical Analysis ◽

Cultural Heritage ◽

Statistical Techniques ◽

Heritage Sites ◽

Historical Heritage ◽

Tourism Services ◽

The City ◽

Non Parametric

The cultural and historical heritage of a city is a major resource for attracting tourists. Therefore, determining how to perceive and identify the characteristics of persons visiting a locality attracted by its heritage is relevant for the purpose of better meeting their expectations and needs. This research focuses on understanding the perceptions, motivations, and satisfaction of women visiting Cordoba (Spain). Thus, on the basis of a questionnaire completed by women visiting Cordoba between the months of June and November 2019, statistical analysis was conducted. Using various multivalent case-grouping techniques, segments of tourists holding similar perceptions of cultural heritage were detected. Moreover, non-parametric statistical techniques highlighted significant differences between the valuations obtained in the various segments. This analysis exposed a segment of women who, known as absorptive tourists, are characterized by a high cultural motivation to visit the city of Cordoba linked to the heritage sites they have visited. The conclusions obtained herein should be useful for adjusting the city’s provision of tourism services to satisfy the demand of female tourists visiting the city.

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SPACIAL VARIABILITY AND SAMPLING DENSITY OF CHEMICAL ATTRIBUTES IN ARCHAEOLOGICAL BLACK EARTH AND NATIVE FOREST SOIL IN MANICORÉ, AM

FLORESTA ◽

10.5380/rf.v44i4.29988 ◽

2014 ◽

Vol 44 (4) ◽

pp. 735 ◽

Cited By ~ 1

Author(s):

Ivanildo Amorim de Oliveira ◽

José Marques Júnior ◽

Milton César Costa Campos ◽

Renato Eleotério de Aquino ◽

Diego Silva Siqueira ◽

...

Keyword(s):

Spatial Variability ◽

Forest Soil ◽

Soil Samples ◽

Spatial Behavior ◽

Statistical Techniques ◽

Native Forest ◽

Sampling Density ◽

Lack Of Information ◽

Chemical Attributes ◽

Regular Spacing

AbstractConsidering the lack of information about spatial behavior of the soil attributes in areas of archaeological black earth and native forest, the objective of this study was to evaluate the spatial variability of chemical attributes and determine the sampling density in soil with archaeological black earth and native forest in the region of Manicoré, AM. The study was conducted in a rural property located in the community of Santo Antônio do Matupi, at the margins of BR 230, Trans-amazon highway, in the region of Manicoré, AM. In these areas were established grids of 70 m x 70 m, with regular spacing of 10 x 10 m, totaling 64 points, then soil samples were collected at a depth of 0.0-0.20 m and 0 , 40 - 0,60 m. Chemical attributes were determined (pH, OM, P, K, Ca, Mg, SB, CTC, V% and H + Al). Data were analyzed using descriptive statistical techniques and geostatistics. Sampling density was determined basing on CV and on the range of the semivariograms. It was verified that the studied attributes showed spatial variability and the area of archaeological black earth presented greater spatial variability than the native forest. Its greater sampling density was determined basing on the range of the adjusted semivariograms.Keywords: Indian black earth; attributes of soil; geostatistics.

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Reconstruction of GRACE Total Water Storage Through Automated Machine Learning

10.5194/gstm2020-53 ◽

2020 ◽

Author(s):

Alex Sun ◽

Bridget Scanlon ◽

Himanshu Save ◽

Ashraf Rateb

Keyword(s):

Machine Learning ◽

Spatial Variability ◽

Large Scale ◽

Water Storage ◽

Total Water ◽

New Paradigm ◽

Satellite Mission ◽

Automated Machine Learning ◽

The Mean ◽

The Impact

<p>The GRACE satellite mission and its follow-on, GRACE-FO, have provided unprecedented opportunities to quantify the impact of climate extremes and human activities on total water storage at large scales. The approximately one-year data gap between the two GRACE missions needs to be filled to maintain data continuity and maximize mission benefits. There is strong interest in using machine learning (ML) algorithms to reconstruct GRACE-like data to fill this gap. So far, most studies attempted to train and select a single ML algorithm to work for global basins. However, hydrometeorological predictors may exhibit strong spatial variability which, in turn, may affect the performance of ML models. Existing studies have already shown that no single algorithm consistently outperformed others over all global basins. In this study, we applied an automated machine learning (AutoML) workflow to perform GRACE data reconstruction. AutoML represents a new paradigm for optimal model structure selection, hyperparameter tuning, and model ensemble stacking, addressing some of the most challenging issues related to ML applications. We demonstrated the AutoML workflow over the conterminous U.S. (CONUS) using six types of ML algorithms and multiple groups of meteorological and climatic variables as predictors. Results indicate that the AutoML-assisted gap filling achieved satisfactory performance over the CONUS. For the testing period (2014/06&#8211;2017/06), the mean gridwise Nash-Sutcliffe efficiency is around 0.85, the mean correlation coefficient is around 0.95, and the mean normalized root-mean square error is about 0.09. Trained models maintain good performance when extrapolating to the mission gap and to GRACE-FO periods (after 2017/06). Results further suggest that no single algorithm provides the best predictive performance over the entire CONUS, stressing the importance of using an end-to-end workflow to train, optimize, and combine multiple machine learning models to deliver robust performance, especially when building large-scale hydrological prediction systems and when predictor importance exhibits strong spatial variability.</p>

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Season dynamics of changes in water microb structure in some water storage reservoirs of Uzbekistan

European Science Review ◽

10.20534/esr-16-7.8-46-48 ◽

2016 ◽

pp. 46-48

Author(s):

B. I. Almatov ◽

N. A. Nuraliyev ◽

S. Y. Kurbanova

Keyword(s):

Water Storage ◽

Storage Reservoirs

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Occurrence of toxic cyanobacteria and microcystin toxin in domestic water storage reservoirs, Egypt

Journal of Water Supply Research and Technology—AQUA ◽

10.2166/aqua.2016.115 ◽

2016 ◽

Vol 65 (5) ◽

pp. 431-440 ◽

Cited By ~ 10

Author(s):

Zakaria A. Mohamed ◽

Mohamed Ali Deyab ◽

Mohamed I. Abou-Dobara ◽

Wesam M. El-Raghi

Keyword(s):

Water Storage ◽

Domestic Water ◽

Toxic Cyanobacteria ◽

Storage Reservoirs

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Design recommendations for reinforced concrete cylindrical storage structures for aqueous materials

Canadian Journal of Civil Engineering ◽

10.1139/l87-079 ◽

1987 ◽

Vol 14 (4) ◽

pp. 542-549

Author(s):

J. C. Jofriet ◽

R. Green ◽

T. I. Campbell

Keyword(s):

Reinforced Concrete ◽

Tensile Stress ◽

Limit State ◽

Water Storage ◽

Lateral Wall ◽

Temperature Gradients ◽

Design Criteria ◽

Storage Reservoirs ◽

Storage Structures ◽

State Criterion

The design of cylindrical non-prestressed concrete storage structures in Ontario does not appear governed by any standard or building code. Many aboveground water storage reservoirs in Ontario have deteriorated badly in a relatively short period of use. Many farm silos suffer from problems similar to those of the water storage reservoirs. This paper is concerned with the selection of the wall thickness and the hoop reinforcement for cylindrical storage tanks and silos for liquids or wet materials where tensile cracking of the concrete is to be limited.Three design criteria are presented. The first limits the circumferential tensile stress in the concrete from lateral wall pressure, shrinkage, and temperature gradients in the wall. The second is concerned with the tension in the hoop reinforcement and guards against collapse. The third limits the crack widths of the cracked concrete section. The most important design loads are discussed. Maximum values for hoop tension are provided for liquid pressures. A design temperature gradient of 15 °C is recommended for design in southern Ontario. As well, appropriate values of shrinkage tensile stress are suggested. The collapse limit state criterion must be evaluated for the hoop steel stresses due to the lateral wall loads. The limit state criterion related to the hoop tensile stress in the concrete must be investigated for all possible load combinations of lateral wall load, shrinkage, and temperature gradients. Reasonable load combination factors have been recommended. Recommendations on the tensile strength of concrete and on appropriate strength factors have been made. Key words: cylindrical tank, design criteria, hoop stresses, reinforced concrete, silo, standpipe, storage of liquids, storage of saturated bulk materials.

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