scholarly journals Aquifer Depletion in the Arlit Mining Area (Tim Mersoï Basin, North Niger)

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1685
Author(s):  
Farida Boubé Dobi ◽  
Eugène Koffi Kouakou ◽  
Yahaya Nazoumou ◽  
Boubacar Abdou Boko ◽  
Sophie Ngomune Edimo ◽  
...  
Keyword(s):  
Flow Direction ◽  
Mining Area ◽  
Mining Activities ◽  
Small Areas ◽  
In Situ Data ◽  
Basin Scale ◽  
Spatio Temporal ◽  
Region Scale ◽  
Land Data Assimilation System ◽  
The One

Located in northwestern Niger, the Tim Mersoï Basin (TMB) is an important mining region in the scale of West Africa. Groundwater is considered the main source of fresh water in the basin, especially for mining activities. It, therefore, appears essential to monitor their responses to these activities. However, no study has been carried out in the Tim Mersoï Basin. This study aims to evaluate the groundwater storage changes (GWSC) of the TMB and to analyze the spatio-temporal evolution of the Tarat aquifer under the effect of mining activities in the Arlit region. For this purpose, Gravity Recovery And Climate Experiment (GRACE), Global Land Data Assimilation System (GLDAS), and in-situ data were used. The results show a variation of the GWS from 2002 to 2019 of about −0.1310 cm/year on the scale of the basin and −0.0109 cm/year in the Arlit mining area. The GWSC at the basin scale and the one at the Arlit region scale were shown to be linked with an RMSE between the two datasets of 0.79. This shows the potential of GRACE for contextualizing studies in small areas. The study also highlighted that the groundwater flow direction was highly modified; the drawdown of the Tarat water table was more than 50 m in the areas heavily impacted by mining activities, with an increasing intensity from the northwest to the southeast of Arlit.

Surface Water Quality Assessment from a Mining Area. Case study, Groapa Burlacu lake, Targu Ocna, Romania

2019 ◽  
Vol 70 (10) ◽  
pp. 3678-3680
Author(s):  
Alina Cochiorca ◽  
Narcis Barsan ◽  
Florin Marian Nedeff ◽  
Ion Sandu ◽  
Emilian Florin Mosnegutu ◽  
...  
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Surface Water Quality ◽  
Water Quality Assessment ◽  
Mining Area ◽  
Physical Parameters ◽  
Mining Activities ◽  
Quality Of Water ◽  
Nacl Concentration ◽  
Water Ph

This paper presents a study on assessment of water quality. According to a study, mining activities have a significant impact on water quality (lakes, surface water and groundwater), which has become a major problem globally. Due to mining and exploitation processes, lakes can be formed around these mines. Also, these lakes have been formed around the world and are steadily increasing. The purpose of this study is to watch the quality of water from the area around mining activities. This study refers to the, Groapa Burlacu lake around the mining exploitation Targu Ocna, Romania. This lake was formed on the northern bottle of the massive salt, strongly affected by the underground activities. Sampling for the determination the concentrations of Cl- and NaCl from the studied area was made at different depths (0 m, -5 m, -10 m, -15 m, -20 m, -25 m, -30 m, -35 m -40 m). Besides these concentrations, physical parameters of the water (pH, turbidity, electrical conductivity, dissolved oxygen and temperature) were also measured. To determine the physical parameters in the monitored area, sampling was done from four different points of the area and then put together for analysis. These parameters were measured on site using portable equipment. The data on the analyzed concentrations indicate that at depths of less than 5.0 m, the NaCl concentration values are more than 250 g/L.

scholarly journals Influence of Precipitation Forcing Uncertainty on Hydrological Simulations with the NASA South Asia Land Data Assimilation System

Hydrology ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 57 ◽  
Author(s):  
Debjani Ghatak ◽  
Benjamin Zaitchik ◽  
Sujay Kumar ◽  
Mir A. Matin ◽  
Birendra Bajracharya ◽  
...  
Keyword(s):  
South Asia ◽  
Hydrological Simulation ◽  
Meteorological Forcing ◽  
In Situ Data ◽  
Precipitation Estimates ◽  
Land Data Assimilation ◽  
Land Data Assimilation System ◽  
Data Assimilation System ◽  
Assimilation System

: Accurate meteorological estimates are critical for process-based hydrological simulation and prediction. This presents a significant challenge in mountainous Asia where in situ meteorological stations are limited and major river basins cross international borders. In this context, remotely sensed and model-derived meteorological estimates are often necessary inputs for distributed hydrological analysis. However, these datasets are difficult to evaluate on account of limited access to ground data. In this case, the implications of uncertainty associated with precipitation forcing for hydrological simulations is explored by driving the South Asia Land Data Assimilation System (South Asia LDAS) using a range of meteorological forcing products. MERRA2, GDAS, and CHIRPS produce a wide range of estimates for rainfall, which causes a widespread simulated streamflow and evapotranspiration. A combination of satellite-derived and limited in situ data are applied to evaluate model simulations and, by extension, to constrain the estimates of precipitation. The results show that available gridded precipitation estimates based on in situ data may systematically underestimate precipitation in mountainous regions and that performance of gridded satellite-derived or modeled precipitation estimates varies systematically across the region. Since no station-based data or product including station data is satisfactory everywhere, our results suggest that the evaluation of the hydrological simulation of streamflow and ET can be used as an indirect evaluation of precipitation forcing based on ground-based products or in-situ data. South Asia LDAS produces reasonable evapotranspiration and streamflow when forced with appropriate meteorological forcing and the choice of meteorological forcing should be made based on the geographical location as well as on the purpose of the simulations.

scholarly journals Assessment of Environmental Geochemistry of Lead-Zinc Mining at Ishiagu Area, Lower Benue Trough, Southeastern Nigeria

2020 ◽  
Vol 9 (1) ◽  
pp. 31 ◽  
Author(s):  
Odika, P.O. ◽  
Anike, O.L. ◽  
Onwuemesi, A.G. ◽  
Odika, N.F. ◽  
Ejeckam, R.B.
Keyword(s):  
Heavy Metals ◽  
Flow Direction ◽  
Environmental Geochemistry ◽  
Zinc Sulphide ◽  
Mining Activities ◽  
Southeastern Nigeria ◽  
Rock Types ◽  
Sulphide Ores ◽  
Lead Zinc ◽  
Concentration Levels

Mining activities have long been recognized as a major source of environmental contamination associated with heavy metals and metalloids. This study evaluated the relationship between the occurrence and mining of lead-zinc sulphide ores at Ishiagu, Nigeria, and heavy metal and metalloid contamination. A comparative study of two zones in the area, with and without mining activities was also made Water, soil, stream sediment and ore samples were analyzed, after acid digestion, using atomic absorption spectrophotometer (AAS).  The concentration levels of seven heavy metals and a metalloid namely Pb, Cu, Ni, Zn, Mn, Co, Cd and as were evaluated. While the highest concentration levels of As, Co and Pb (5.20 mg/l, 0.54 mg/l and 3.40 mg/l respectively) were found in water, those of Ni and Mn (2.26 mg/l and 5.48 mg/l respectively) occurred in soil.  For Cu and Zn, highest levels of concentration (2.80 mg/l and 0.41 mg/l respectively) occurred in stream sediments. The variations in the concentration levels of these elements in varying geologic media (soil, water and sediment) indicate influence of rock types, human activities and media physiochemical characteristics. Geostatistical analyses using QQPlot, semivariogram and kriging showed normal distribution of these elements. Distribution and dispersion patterns of the heavy metals indicated increase in concentration levels in the local stream flow direction. Pb, Cu, As, Cd, Mn, and Ni concentrations had reached pollutant levels in water based on WHO standards, while Zn level is below. Since the local people use untreated surface water and groundwater for drinking and other domestic purposes, soil for farming and lead for cosmetics, long term exposure poses significant health risk for humans, animals and plants.

scholarly journals Age of the Post-rift Sequence I from the Araripe Basin, Lower Cretaceous, NE Brazil: implications for spatio-temporal correlation

2021 ◽  
Vol 24 (1) ◽  
pp. 37-46
Author(s):  
João Carlos Coimbra ◽  
Tiago Menezes Freire
Keyword(s):  
Critical Review ◽  
Lower Cretaceous ◽  
Temporal Correlation ◽  
Isotopic Analysis ◽  
The Other ◽  
Stratigraphic Framework ◽  
Spatio Temporal ◽  
Radiometric Ages ◽  
The One ◽  
Do So

A robust biostratigraphic zonation based on microfossils supports the stratigraphic framework and correlation of the interior basins of the Lower Cretaceous of NE Brazil. This zonation has also allowed correlations with coeval sections in the Brazilian marginal basins and in the Gabon and Congo basins (central-west Africa). These records, consisting mainly of non-marine sediments, were a great challenge with regard to the correlation with the International Chronostratigraphic Chart. Therefore, local stages were used, the most recent being the Alagoas local Brazilian Stage, with which the Post-rift Sequence I of the Araripe Basin is related. Regarding lithostratigraphy, this sequence includes the Rio da Batateira (Barbalha for some authors) and Santana formations, the last one with the famous Crato, Ipubi, and Romualdo members, from the base to the top. Although currently there is a consensus on the age of the Alagoas local Brazilian Stage in the Araripe Basin, recently a new age for at least part of the Post-rift Sequence I was proposed. This new proposal, based on isotopic analysis of Re-Os, arose as a panacea to correlate the Rio da Batateira Formation and the Crato and Ipubi members with the international stages. Surprisingly, their authors, although on the one hand, they seem to underestimate biostratigraphic results, on the other they seek to support their proposal from microfossils studied by previous authors, but they do so in an inappropriate way, leading readers to misinterpret their results. Therefore, this paper presents a critical review on the age of the Alagoas local Brazilian Stage in the Araripe Basin and nearby basins, refuting a Barremian age for part of the Post-rift Sequence I. Keywords: Alagoas local Brazilian Stage, biostratigraphy, ostracods, palynomorphs, radiometric ages.

scholarly journals Validation of the TOLNet Lidars: The Southern California Ozone Observation Project (SCOOP)

2018 ◽  
Author(s):  
Thierry Leblanc ◽  
Mark A. Brewer ◽  
Patrick S. Wang ◽  
Maria Jose Granados-Munoz ◽  
Kevin B. Strawbridge ◽  
...  
Keyword(s):  
Tropospheric Ozone ◽  
Southern California ◽  
Measurement Techniques ◽  
Reference Network ◽  
Control Effort ◽  
The North ◽  
Lidar Measurements ◽  
Spatio Temporal ◽  
To Come ◽  
The One

Abstract. The North-America-based Tropospheric Ozone Lidar Network (TOLNet) was recently established to provide high spatio-temporal vertical profiles of ozone, to better understand physical processes driving tropospheric ozone variability, and to validate the tropospheric ozone measurements of upcoming space-borne missions such as Tropospheric Emissions: Monitoring Pollution (TEMPO). The network currently comprises six tropospheric ozone lidars, four of which are mobile instruments deploying to the field a few times per year, based on campaign and science needs. In August 2016, all four mobile TOLNet lidars were brought to the fixed TOLNet site of JPL-Table Mountain Facility for the one-week-long Southern California Ozone Observation Project (SCOOP). This inter-comparison campaign, which included 400 hours of lidar measurements and 18 ozonesondes launches, allowed for the unprecedented simultaneous validation of five of the six TOLNet lidars. For measurements between 3 and 10 km above sea level, a mean difference of 0.7 ppbv (1.7 %), with a root-mean-square deviation of 1.6 ppbv or 2.4 % was found between the lidars and ozonesondes, which is well within the combined uncertainties of the two measurement techniques. The few minor differences identified were typically associated with the known limitations of the lidars at the profiles altitude extremes (i.e., first 1 km above ground and at the instruments highest retrievable altitude). As part of a large homogenization and quality control effort within the network, many aspects of the TOLNet in-house data processing algorithms were also standardized and validated. This thorough validation of both the measurements and retrievals builds confidence in the high quality and reliability of the TOLNet ozone lidar profiles for many years to come, making TOLNet a valuable ground-based reference network for tropospheric ozone profiling.

The limitations of in situ data for validating satellite-derived spatio-temporal ocean products.

2021 ◽  
Author(s):  
Rory Scarrott ◽  
Fiona Cawkwell ◽  
Mark Jessopp ◽  
Caroline Cusack
Keyword(s):  
Surface Temperature ◽  
Surface Heterogeneity ◽  
Ocean Surface ◽  
Bias Reduction ◽  
Data Validation ◽  
Near Surface ◽  
In Situ Data ◽  
Spatio Temporal ◽  
Image Pixels

<p>The Ocean-surface Heterogeneity MApping (OHMA) algorithm is an objective, replicable approach to map the spatio-temporal heterogeneity of ocean surface waters. It is used to processes hypertemporal, satellite-derived data and produces a single-image surface heterogeneity (SH) dataset for the selected parameter of interest. The product separates regions of dissimilar temporal characteristics. Data validation is challenging because it requires In-situ observations at spatial and temporal resolutions comparable to the hyper-temporal inputs. Validating this spatio-temporal product highlighted the need to optimise existing vessel-based data collection efforts, to maximise exploitation of the rapidly-growing hyper-temporal data resource.</p><p>For this study, the SH was created using hyper-temporal 1km resolution satellite derived Sea Surface Temperature (SST) data acquired in 2011. Underway ship observations of near surface temperature collected on multiple scientific surveys off the Irish coast in 2011 were used to validate the results. The most suitable underway ship SST data were identified in ocean areas sampled multiple times and with representative measurements across all seasons.</p><p>A 3-stage bias reduction approach was applied to identify suitable ocean areas. The first bias reduction addressed temporal bias, i.e., the temporal spread of available In-situ ship transect data across each satellite image pixel. Only pixels for which In-situ data were obtained at least once in each season were selected; resulting in 14 SH image pixels deemed suitable out of a total of 3,677 SH image pixels with available In-situ data. The second bias reduction addressed spatial bias, to reduce the influence of over-sampled areas in an image pixel with a sub-pixel approach. Statistical dispersion measures and statistical shape measures were calculated for each of the sets of sub-pixel values. This gave heterogeneity estimates for each cruise transit of a pixel area. The third bias reduction addressed bias of temporally oversampled seasons. For each transit-derived heterogeneity measure, the values within each season were averaged, before the annual average value was derived across all four seasons in 2011.</p><p>Significant associations were identified between satellite SST-derived SH values, and In-situ heterogeneity measures related to shape; absolute skewness (Spearman’s Rank, n=14, ρ[12]= +0.5755, P<0.05), and kurtosis (Spearman’s Rank, n=14, ρ[12] = 0.5446, P < 0.05). These are a consequence of (i) locally-extreme measurements, and/or (ii) increased presence of sharp transitions detected spatially by In-situ data. However, the number and location of suitable In-situ validation sites precluded a robust validation of the SH dataset (14 pixels located in Irish waters, for a dataset spanning the North Atlantic). This requires more targeted data. The approach would have benefited from more samples over the winter season, which would have enabled more offshore validation sites to be incorporated into the analysis. This is a challenge that faces satellite product developers, who want to deliver spatio-temporal information to new markets. There is a significant opportunity for dedicated, transit-measured (e.g. Ferry box data), validation sites to be established. These could potentially synergise with key nodes in global shipping routes to maximise data collected by vessels of opportunity, and ensure consistent data are collected over the same area at regular intervals.</p>

The spatio-temporal evolution of groundwater dependent precipitation

2021 ◽  
Author(s):  
Cristina Passet ◽  
Lan Wang-Erlandsson ◽  
Yoshihide Wada ◽  
Agnes Pranindita ◽  
Agatha De Boer
Keyword(s):  
Temporal Evolution ◽  
Groundwater Resources ◽  
Terrestrial Ecosystems ◽  
Global Scale ◽  
Groundwater Abstraction ◽  
Groundwater Availability ◽  
Basin Scale ◽  
The Usa ◽  
Spatio Temporal ◽  
Selection Of

<div><span>A<strong> </strong>substantial portion of groundwater abstracted from aquifers is used for irrigation and evaporated to the atmosphere, potentially contributing towards downwind precipitation. While the fate of evaporation fluxes from land have been analysed, the atmospheric pathways of evaporation originating from groundwater have not yet been globally quantified. This study analysed the geographical distribution, the seasonality and the magnitude of groundwater-dependent precipitation (Pgw) </span><span>at a global scale and for a selection of countries and river basins. The Eulerian moisture tracking WAM-2layers model was used to process meteorological and groundwater abstraction input data from 1980 to 2010.  Results show considerable contributions of groundwater to precipitation downwind of the most heavily irrigated areas, leading to net groundwater losses over these areas. Globally, 40% of the Pgw </span><span>precipitates directly in the oceans, and do not contribute to biomass production in terrestrial ecosystems. Some of the countries with the highest rates of groundwater abstraction (India, the USA, Pakistan and Iran), receive low volumes of Pgw </span><span>and are net losers of groundwater resources. The countries with the highest net gain of groundwater are China, Canada and Russia. At river basin scale, the Indus, Ganges and Mississippi basins are net losers of groundwater to downwind Pgw</span><span>, while the Yangtze, Tarim and Brahmaputra basins receive more Pgw </span><span>than their groundwater withdrawals. The share of precipitation that originates from groundwater varies considerably with seasons, and can be especially high when low local precipitation levels occur in combination with high upwind groundwater abstraction. Furthermore, precipitation dependence on </span><span>groundwater (ρgw)</span><span>, has steadily increased between 1980 to 2010 in all studied areas and globally. Our study suggests that the countries and basins with a high and increasing dependency on ρgw </span><span>to support their precipitation can be vulnerable to groundwater availability upwind.</span></div>

Perfil decisional, género y práctica deportiva en deporte en edad escolar (Decisional profile, gender and sports practice in sports at school age)

Retos ◽  
2021 ◽  
Vol 43 ◽  
pp. 379-387
Author(s):  
Francisco Javier Vázquez Ramos ◽  
Patricia Irene Sosa-González ◽  
Juan De Pablos Pons
Keyword(s):  
Secondary Education ◽  
School Age ◽  
Decision Making Capacity ◽  
Final Sample ◽  
Gender And Sports ◽  
Temporal Aspects ◽  
Toma De Decisiones ◽  
Spatio Temporal ◽  
Para Determinar ◽  
The One

  El objetivo de este estudio ha sido determinar el perfil decisional de chicos y chicas en edad escolar basado en aspectos espacio-temporales a través del software “Juego Interactivo de Voleibol” (JIVBⓇ), en función de diferentes variables: dificultad espacio-temporal, tipo de práctica deportiva, edad, sexo y tiempo de práctica deportiva. La muestra ha sido conformada por la totalidad de los clubes de categoría infantil de la ciudad de Sevilla de las modalidades de balonmano, voleibol y atletismo, así como de alumnado de Enseñanza Secundaria Obligatoria (ESO) de un Instituto de Enseñanza Secundaria que no practicaba más actividad físico-deportiva que la realizada en sus clases de educación física. Además, para completar la muestra a nivel deportivo se optó por incluir a un club de voleibol y a un club de atletismo de poblaciones limítrofes con Sevilla capital, quedando la muestra final constituida por 109 participantes, de ambos sexos, de 12-14 años. Para determinar el perfil decisional se utilizó el JIVB y se llevaron a cabo análisis descriptivos e inferenciales. Los resultados muestran que no existen diferencias significativas en la capacidad de toma de decisiones, aunque sí se puede hablar de tendencias.  Abstract. The objective of this study was to determine the decisional profile of school-age boys and girls based on spatio-temporal aspects through the software "Interactive Volleyball Game" (JIVBⓇ), based on different variables: spatio-temporal difficulty, type of sports practice, age, sex and time of sports practice. The sample has been made up of all the children's category clubs in the city of Seville in the modalities of handball, volleyball and athletics, as well as students of Compulsory Secondary Education (ESO) of a Secondary Education Institute that did not practice anymore physical-sporting activity than the one carried out in their physical education classes. In addition, to complete the sample at the sporting level, it was decided to include a volleyball club and an athletics club from neighboring towns with Seville, leaving the final sample consisting of 109 participants, of both sexes, aged 12-14 years. To determine the decisional profile, the JIVB was used and descriptive and inferential analyzes were carried out. The results show that there are no significant differences in decision-making capacity, although it is possible to speak of trends.

scholarly journals History-based Explanatory Framework for Procreative Behaviour of Aboriginal People of Canada

2008 ◽  
Vol 35 (1) ◽  
pp. 159
Author(s):  
Anatole Romaniuk
Keyword(s):  
Aboriginal People ◽  
Low Fertility ◽  
Aboriginal Peoples ◽  
Traditional Values ◽  
Explanatory Framework ◽  
Real Population ◽  
Theoretical Investigations ◽  
Spatio Temporal ◽  
The One ◽  
Challenging Question

The transition from traditional high to modern low fertility is in the forefront of empirical and theoretical investigations in contemporary aboriginal demography. The challenging question therein remains why its fertility has started to decline a century or so after the rest of Canada, and why it continues to trail the latter by a considerable lag. The objective of this paper is to present a history-based explanatory framework of the childbearing behaviour of Canadian aboriginal peoples, as it has evolved over time from the very first contact with Europeans to our day. Turning to existing theories for possible elucidation of these idiosyncrasies, we find that while accounting for certain aspects, they leave others unexplained. History provides a more satisfying explanation when we cast an eye not on the “abstract” population, “ideal-type” or what we today like to call “model”, but on real population, or family thereof, in its spatio-temporal context. The “between-two-cultures” paradigm presented here, based on ethnocentricity and dependency, could be seen as a an explanatory paradigm of competing forces on the Canadian aboriginals: on the one hand, those pushing toward modern norms of childbearing; and on the other, traditional values and structures, as shattered as they are, with their pro-natalist ideologies resisting normative changes.

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