scholarly journals Monitoring water quality in estuarine environments: lessons from the MAGEST monitoring programme in the Gironde fluvial-estuarine system

2010 ◽  
Vol 7 (6) ◽  
pp. 9411-9436
Author(s):  
H. Etcheber ◽  
S. Schmidt ◽  
A. Sottolichio ◽  
E. Maneux ◽  
G. Chabaux ◽  
...  
Keyword(s):  
Water Quality ◽  
Environmental Changes ◽  
Monitoring Programme ◽  
Reference Database ◽  
Estuarine System ◽  
Gironde Estuary ◽  
Future Evolution ◽  
External Forcings ◽  
Frequency Monitoring

Abstract. The Gironde estuary, one of the largest European ones, presents temporary low dissolved oxygen content in its fluvial section close to the Bordeaux urban area. In a context of population growth and of long-term environmental changes, the development of a high-frequency monitoring programme of the fluvial-estuarine system of the Gironde, called MAGEST (MArel Gironde ESTuary), had appeared essential to address current and future water-quality issues/evaluations. The objectives of the MAGEST survey programme are to establish a reference database to improve the knowledge of the Gironde estuary functioning, encompassing the aspects of hydrology, sediment dynamics and biogeochemistry. Through examples of results from intratidal to seasonal time scales, we demonstrate how such a time-series is of valuable interest to extract the main trends of its functioning and of the water quality in relation to external forcings (climatology, urban wastes, land use, ...) and to predict the future evolution of the Gironde estuary with global and environmental changes.

scholarly journals Monitoring water quality in estuarine environments: lessons from the MAGEST monitoring program in the Gironde fluvial-estuarine system

2011 ◽  
Vol 15 (3) ◽  
pp. 831-840 ◽  
Author(s):  
H. Etcheber ◽  
S. Schmidt ◽  
A. Sottolichio ◽  
E. Maneux ◽  
G. Chabaux ◽  
...  
Keyword(s):  
Water Quality ◽  
High Frequency ◽  
Environmental Changes ◽  
Monitoring Program ◽  
Reference Database ◽  
Estuarine System ◽  
Gironde Estuary ◽  
Future Evolution ◽  
Frequency Monitoring

Abstract. The Gironde Estuary, one of the largest European ones, presents temporary low dissolved oxygen content in its fluvial section close to the Bordeaux urban area. In a context of population growth and of long-term environmental changes, the development of a high-frequency monitoring programme of the fluvial-estuarine system of the Gironde, called MAGEST (MArel Gironde ESTuary), had appeared essential to address current and future water-quality issues/evaluations. The objectives of the MAGEST survey program are to establish a reference database to improve the knowledge of the Gironde Estuary functioning, encompassing the aspects of hydrology, sediment dynamics and biogeochemistry. Through examples of results from intratidal to seasonal time scales, we demonstrate how such a long-term, high-frequency monitoring of a fluvio-estuarine system is of valuable interest to extract the main trends of its functioning and of the water quality in relation to external forcings (climatology, urban wastes, land use, ...) and to predict the future evolution of an estuary with global and environmental changes.

scholarly journals Monitoring the Spatial and Temporal Variations in The Water Surface and Floating Algal Bloom Areas in Dongting Lake Using a Long-Term MODIS Image Time Series

2020 ◽  
Vol 12 (21) ◽  
pp. 3622
Author(s):  
Mengmeng Cao ◽  
Kebiao Mao ◽  
Xinyi Shen ◽  
Tongren Xu ◽  
Yibo Yan ◽  
...  
Keyword(s):  
Water Quality ◽  
Human Activities ◽  
Water Surface ◽  
Algal Bloom ◽  
Environmental Changes ◽  
Climatic Factors ◽  
Dongting Lake ◽  
Dynamic Learning ◽  
Traditional Methods

Significant water quality changes have been observed in the Dongting Lake region due to environmental changes and the strong influence of human activities. To protect and manage Dongting Lake, the long-term dynamics of the water surface and algal bloom areas were systematically analyzed and quantified for the first time based on 17 years of Moderate Resolution Imaging Spectroradiometer (MODIS) observations. The traditional methods (index-based threshold algorithms) were optimized by a dynamic learning neural network (DL-NN) to extract and identify the water surface area and algal bloom area while reducing the extraction complexity and improving the extraction accuracy. The extraction accuracy exceeded 94.5% for the water and algal bloom areas, and the analysis showed decreases in the algal bloom and water surface areas from 2001–2017. Additionally, the variations in the water surface and algal bloom areas are greatly affected by human activities and climatic factors. The results of these analyses can help us better monitor human contamination in Dongting Lake and take measures to control the water quality during certain periods, which is crucial for future management. Moreover, the traditional methods optimized by the DL-NN used in this study can be extended to other inland lakes to assess and monitor long-term temporal and spatial variations in algal bloom areas and can also be used to acquire baseline information for future assessments of the water quality of lakes.

scholarly journals Paleontological methods in environmental science

1992 ◽  
Vol 6 ◽  
pp. 40-40
Author(s):  
Grace S. Brush ◽  
Humaira Khan
Keyword(s):  
Water Quality ◽  
Environmental Conditions ◽  
Human Disturbance ◽  
Large Scale ◽  
Environmental Changes ◽  
Nitrogen And Phosphorus ◽  
Ecological Requirements ◽  
Inorganic Substances ◽  
Stratigraphic Record

Long term environmental changes, induced both by natural and anthropogenic causes, cannot be assessed by looking solely at historical records of temperature, rainfall, water quality, etc. Frequently, such records are nonexistent. Where they do exist, they are often too short to be of much use. However, sediments contain a stratigraphic record of environmental change that allows comparison of the historic period influenced largely by humans, with prehistoric time when climate was the major determinant of environmental conditions.The stratigraphic record contains various fossilized organic materials which reflect environmental conditions at the time of the their deposition. Most abundant are pollen and spores of aquatic and terrestrial plants. Correspondence between pollen assemblages and vegetation has been found in all parts of the world. Therefore stratigraphic changes in pollen taxa reveal much information regarding the vegetational history of a region. Knowledge of the ecological requirements of various taxa can then be used to infer past climatic conditions. For example, dominance of Juglans (walnut) pollen indicates wet conditions while abundance of Pteridium (bracken fern) spores is an indicator of fire, suggesting drier conditions. Pollen can also be used to trace human disturbance to the environment. Sharp increases in the pollen of Ambrosia (ragweed) in sediment cores indicate large scale land clearance by man.Seeds preserved in sediments provide another measure of temporal vegetational change. Generally, seeds are not dispersed far from the parent plant; hence they provide a more local record of vegetation than pollen. A decrease in seeds of aquatic plants and increase in seeds of higher ground taxa when accompanied by increased sedimentation rates is an indicator of infilling of an aquatic environment. If unaccompanied by increased sedimentation, the change more likely represents lowering of sea level. Disappearance of seeds of taxa sensitive to turbidity and eutrophication provide another long term record of human disturbance.Distributions of diatoms are affected by temperature, salinity, oxygen, light availability and nutrient levels in the water. Therefore changes in diatom species preserved in the sediments can be used as indicators of climate, turbidity, anoxia and eutrophication in aquatic ecosystems.Many inorganic substances preserved in sediments also provide a long term record of changes in the environment. Nitrogen and phosphorus can be measured in cores and used as a surrogate record of water quality in lakes and estuaries. Sharp increases in sedimentary accumulation of metals record wastewater discharge and fuel emissions, related to human activity.

scholarly journals Citizen Scientists Contribute to Real-Time Monitoring of Lake Water Quality Using 3D Printed Mini Secchi Disks

2021 ◽  
Vol 3 ◽  
Author(s):  
Grinson George ◽  
Nandini N. Menon ◽  
Anas Abdulaziz ◽  
Robert J. W. Brewin ◽  
P. Pranav ◽  
...  
Keyword(s):  
Water Quality ◽  
Real Time ◽  
Citizen Science ◽  
Economic Benefits ◽  
Scientific Data ◽  
Series Data ◽  
Estuarine System ◽  
Water Colour

Citizen science aims to mobilise the general public, motivated by curiosity, to collect scientific data and contribute to the advancement of scientific knowledge. In this article, we describe a citizen science network that has been developed to assess the water quality in a 100 km long tropical lake-estuarine system (Vembanad Lake), which directly or indirectly influences the livelihood of around 1.6 million people. Deterioration of water quality in the lake has resulted in frequent outbreaks of water-associated diseases, leading to morbidity and occasionally, to mortality. Water colour and clarity are easily measurable and can be used to study water quality. Continuous observations on relevant spatial and temporal scales can be used to generate maps of water colour and clarity for identifying areas that are turbid or eutrophic. A network of citizen scientists was established with the support of students from 16 colleges affiliated with three universities of Kerala (India) and research institutions, and stakeholders such as houseboat owners, non-government organisations (NGOs), regular commuters, inland fishermen, and others residing in the vicinity of Vembanad Lake and keen to contribute. Mini Secchi disks, with Forel-Ule colour scale stickers, were used to measure the colour and clarity of the water. A mobile application, named “TurbAqua,” was developed for easy transmission of data in near-real time. In-situ data from scientists were used to check the quality of a subset of the citizen observations. We highlight the major economic benefits from the citizen network, with stakeholders voluntarily monitoring water quality in the lake at low cost, and the increased potential for sustainable monitoring in the long term. The data can be used to validate satellite products of water quality and can provide scientific information on natural or anthropogenic events impacting the lake. Citizens provided with scientific tools can make their own judgement on the quality of water that they use, helping toward Sustainable Development Goal 6 of clean water. The study highlights potential for world-wide application of similar citizen-science initiatives, using simple tools for generating long-term time series data sets, which may also help monitor climate change.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

Modelling the Effects of Acid Deposition: Estimation of Long-Term Water Quality Responses in Forested Catchments in Finland

1988 ◽  
Vol 19 (2) ◽  
pp. 99-120 ◽  
Author(s):  
A. Lepistö ◽  
P. G. Whitehead ◽  
C. Neal ◽  
B. J. Cosby
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Base Cations ◽  
Surface Water Quality ◽  
Mineral Weathering ◽  
Co2 Solubility ◽  
Forested Catchments ◽  
Deposition Rates ◽  
Magic Model

A modelling study has been undertaken to investigate long-term changes in surface water quality in two contrasting forested catchments; Yli-Knuutila, with high concentrations of base cations and sulphate, in southern Finland; and organically rich, acid Liuhapuro in eastern Finland. The MAGIC model is based on the assumption that certain chemical processes (anion retention, cation exchange, primary mineral weathering, aluminium dissolution and CO2 solubility) in catchment soils are likely keys to the responses of surface water quality to acidic deposition. The model was applied for the first time to an organically rich catchment with high quantities of humic substances. The historical reconstruction of water quality at Yli-Knuutila indicates that the catchment surface waters have lost about 90 μeq l−1 of alkalinity in 140 years, which is about 60% of their preacidification alkalinity. The model reproduces the declining pH levels of recent decades as indicated by paleoecological analysis. Stream acidity trends are investigated assuming two scenarios for future deposition. Assuming deposition rates are maintained in the future at 1984 levels, the model indicates that stream pH is likely to continue to decline below presently measured levels. A 50% reduction in deposition rates would likely result in an increase in pH and alkalinity of the stream, although not to estimated preacidification levels. Because of the high load of organic acids to the Liuhapuro stream it has been acid before atmospheric pollution; a decline of 0.2 pH-units was estimated with increasing leaching of base cations from the soil despite the partial pH buffering of the system by organic compounds.

Long Term Monitoring of the Macrobenthos of the Upper Clyde Estuary

1984 ◽  
Vol 16 (5-7) ◽  
pp. 359-373 ◽  
Author(s):  
Anne R Henderson
Keyword(s):  
Water Quality ◽  
Seasonal Variation ◽  
Organic Pollution ◽  
Long Term Changes ◽  
Pollution Loading ◽  
Faunal Density ◽  
History Of ◽  
Long Term Monitoring ◽  
Term Monitoring

The sublittoral macrobenthic invertebrate populations of the Upper Clyde Estuary are described. The estuary has a long history of organic pollution. The long term changes in species composition, faunal density and dominance patterns between 1974 and 1980 are presented. The fauna is dominated by brackish, pollution tolerant oligochaetes and polychaetes. Fluctuations in populations can be related to both seasonal variation in environmental conditions and long term improvements in water quality through a reduction in pollution loading to the estuary.

Investigation of a New Approach to Predict Water Quality Extremes with a Case Study of Chemical Determinands in Stream Water

1991 ◽  
Vol 24 (6) ◽  
pp. 25-33
Author(s):  
A. J. Jakeman ◽  
P. G. Whitehead ◽  
A. Robson ◽  
J. A. Taylor ◽  
J. Bai
Keyword(s):  
Water Quality ◽  
Stream Water ◽  
Probability Distributions ◽  
Management Strategies ◽  
Hybrid Modelling ◽  
Trend Model ◽  
Environmental Extremes ◽  
Modelling Approach

The paper illustrates analysis of the assumptions of the statistical component of a hybrid modelling approach for predicting environmental extremes. This shows how to assess the applicability of the approach to water quality problems. The analysis involves data on stream acidity from the Birkenes catchment in Norway. The modelling approach is hybrid in that it uses: (1) a deterministic or process-based description to simulate (non-stationary) long term trend values of environmental variables, and (2) probability distributions which are superimposed on the trend values to characterise the frequency of shorter term concentrations. This permits assessment of management strategies and of sensitivity to climate variables by adjusting the values of major forcing variables in the trend model. Knowledge of the variability about the trend is provided by: (a) identification of an appropriate parametric form of the probability density function (pdf) of the environmental attribute (e.g. stream acidity variables) whose extremes are of interest, and (b) estimation of pdf parameters using the output of the trend model.

LONG-TERM WILDFIRE-RELATED CHEMICAL IMPACTS ON WATER QUALITY WITHIN THE MALIBU CREEK COASTAL WATERSHED

2020 ◽  
Author(s):  
Christian L. Hoover ◽  
◽  
Kyle H. Ikeda ◽  
Erin E. Schmitt ◽  
Michael F. Kushner ◽  
...  
Keyword(s):  
Water Quality ◽  
Coastal Watershed
Sign in / Sign up

Export Citation Format

Share Document