Suchergebnisse

At first sight, European regions appear to have abundant water resources as they are generally characterised by a temperate climate. Sustainable water practices do not necessarily come as a priority topic of interest as water availability is not commonly perceived as an issue. This is especially the case in a country such as Belgium often described as a rainy country. However, over the last few years, some elements such as the creation of a drought unit in Wallonia, the engagement of the Flemish government in a Blue Deal and restrictions on water use during the summer in multiple Belgian municipalities have brought to the public attention the potential risks of a lack of water. So what is the situation of Belgium in terms of water availability? Should it be a topic of concern? This article intends to shed some light on these questions, with the scientific input of Marnik Vanclooster, Professor and researcher at the Earth of Life Institute at UCLouvain in hydrology and water management, for a better understanding of the Belgian water context.

At first sight, European regions appear to have abundant water resources as they are generally characterised by a temperate climate. Sustainable water practices do not necessarily come as a priority topic of interest as water availability is not commonly perceived as an issue. This is especially the case in a country such as Belgium often described as a rainy country. However, over the last few years, some elements such as the creation of a drought unit in Wallonia, the engagement of the Flemish government in a Blue Deal and restrictions on water use during the summer in multiple Belgian municipalities have brought to the public attention the potential risks of a lack of water. So what is the situation of Belgium in terms of water availability? Should it be a topic of concern? This article intends to shed some light on these questions, with the scientific input of Marnik Vanclooster, Professor and researcher at the Earth of Life Institute at UCLouvain in hydrology and water management, for a better understanding of the Belgian water context.

The Water Governance Facility, a partnership between UN Development Program and the Stockholm International Institute, defines water governance as follows: "Water governance refers to the political, social, economic and administrative systems in place that influence water's use and management. Essentially, who gets what water, when and how, and who has the right to water and related services, and their benefits." (www.watergovernance.org, visited 28 august 18). Given such definition, it looks evident that effective and improved water governance can only be based on an in-depth knowledge of the water resource in a given water management unit (region / country / basin). In this presentation, we therefore illustrate how modern information systems, tools and services can be developed for different water functions, supporting sustainable water management and appropriate water governance. We illustrate the new opportunities to improve the knowledge base (big data technology, massive parallel processing of water data, citizen science …), but also show challenges associated with these new technologies, which underpin current developments in hydrological and water management science. We focus in this presentation on groundwater resources for drinking water provision functions.

The Water Governance Facility, a partnership between UN Development Program and the Stockholm International Institute, defines water governance as follows: "Water governance refers to the political, social, economic and administrative systems in place that influence water's use and management. Essentially, who gets what water, when and how, and who has the right to water and related services, and their benefits." (www.watergovernance.org, visited 28 august 18). Given such definition, it looks evident that effective and improved water governance can only be based on an in-depth knowledge of the water resource in a given water management unit (region / country / basin). In this presentation, we therefore illustrate how modern information systems, tools and services can be developed for different water functions, supporting sustainable water management and appropriate water governance. We illustrate the new opportunities to improve the knowledge base (big data technology, massive parallel processing of water data, citizen science …), but also show challenges associated with these new technologies, which underpin current developments in hydrological and water management science. We focus in this presentation on groundwater resources for drinking water provision functions.

Le Bassin méditerranéen est un "hotspot" des changements globaux. Ces changements se concrétisent par une croissance démographique concentrée sur la zone littorale, par un vieillissement de la population rurale, par un changement climatique accru et accentué par une modification majeure du contexte institutionnel et politique lié aux "Printemps arabes"

Le Bassin méditerranéen est un "hotspot" des changements globaux. Ces changements se concrétisent par une croissance démographique concentrée sur la zone littorale, par un vieillissement de la population rurale, par un changement climatique accru et accentué par une modification majeure du contexte institutionnel et politique lié aux "Printemps arabes"

Citizen Science (CS) has been emerging in the last decade as a new field of environmental monitoring involving a direct collaboration between everyday citizens and scientists. In Tunisia, several recent governmental efforts aimed at reinforcing and renovating the existing official water monitoring systems. However, the lack of reliable hydrological data is still an issue, which could be better addressed through integrating a CS approach. The latter approach is tested for rainfall monitoring in the Medjerda catchment in Tunisia using cost-effective and publicly available manual rain gauges. We used a step-by-step approach to target, engage and train citizens on using the monitoring tools and transmitting the data to a user-friendly online platform. The ongoing approach involved 7 citizens from different generations and different educational backgrounds. The collected daily CS data are compared with data from reference stations. Results yield a significant correlation between CS data collected at 3 different sites and the reference stations with r (Pearson Correlation Coefficient (PCC)) ranges between 0.91 and 0.98 for all citizens. Student's t-test was applied to evaluate the significance of the agreement between the CS and reference data. In addition, the variability of the CS data is compared with the variability associated with the official governmental data. The CS approach delivered consistent outcomes to complement existing Tunisian monitoring systems, and also to enhance innovation, adaptation, and local capacity building in the Tunisian water sector.

Citizen Science (CS) has been emerging in the last decade as a new field of environmental monitoring involving a direct collaboration between everyday citizens and scientists. In Tunisia, several recent governmental efforts aimed at reinforcing and renovating the existing official water monitoring systems. However, the lack of reliable hydrological data is still an issue, which could be better addressed through integrating a CS approach. The latter approach is tested for rainfall monitoring in the Medjerda catchment in Tunisia using cost-effective and publicly available manual rain gauges. We used a step-by-step approach to target, engage and train citizens on using the monitoring tools and transmitting the data to a user-friendly online platform. The ongoing approach involved 7 citizens from different generations and different educational backgrounds. The collected daily CS data are compared with data from reference stations. Results yield a significant correlation between CS data collected at 3 different sites and the reference stations with r (Pearson Correlation Coefficient (PCC)) ranges between 0.91 and 0.98 for all citizens. Student's t-test was applied to evaluate the significance of the agreement between the CS and reference data. In addition, the variability of the CS data is compared with the variability associated with the official governmental data. The CS approach delivered consistent outcomes to complement existing Tunisian monitoring systems, and also to enhance innovation, adaptation, and local capacity building in the Tunisian water sector.

The recently adopted UN Sustainable Development Goals (SDGs) encompasses a specific goal forwater (SDG-6). The target 6.4 deals with water scarcity and refers to two main indicators: water use efficiency and water stress (WS), monitored by the UN statistical services yearly at the country level. Yet, for more efficient development planning, indicators should also be provided with higher spatial and temporal resolutions. This study presents a data-driven method allowing to disaggregate the WS indicator at higher spatial and temporal resolution. We applied the method for the Medjerda catchment in Tunisia, known as being severely water-stressed. We disaggregated theWS indicator fromthe overall catchment to the administrative regional level at yearly and monthly scales. In order to overcome poorly documented irrigation water withdrawals, two approaches were adopted: 1)we used yearly governmental data at both catchment and regions scales; 2)we replaced governmental irrigation data by remote sensing-based irrigation estimation. First Order Uncertainty Analysis (FOUA)was performed to characterize the uncertainty associated with the assessment ofWS. Results reveal that theWS at the scale of the catchment increases considerably in recent years, exceeding 50% from2005 and surpassing the 100% threshold in 2015 and 2016 (102%, 108% respectively). The two adopted approaches result in similar WS trends. However, the second approach yields higherWS values compared to the first approach (144% versus 108% in 2016). Themonthly-disaggregatedWSat catchment scale exhibits a similar increasing trend. The highestWSvalues are at the end of the fall and during the summer season,which ismainly due to the increasing demand for irrigation and drinking water. Siliana region is the most affected byWS, while Beja is the least affected. The FOUA shows that the integration of remote sensing-based irrigation data reduces theWS uncertainty.

The recently adopted UN Sustainable Development Goals (SDGs) encompasses a specific goal forwater (SDG-6). The target 6.4 deals with water scarcity and refers to two main indicators: water use efficiency and water stress (WS), monitored by the UN statistical services yearly at the country level. Yet, for more efficient development planning, indicators should also be provided with higher spatial and temporal resolutions. This study presents a data-driven method allowing to disaggregate the WS indicator at higher spatial and temporal resolution. We applied the method for the Medjerda catchment in Tunisia, known as being severely water-stressed. We disaggregated theWS indicator fromthe overall catchment to the administrative regional level at yearly and monthly scales. In order to overcome poorly documented irrigation water withdrawals, two approaches were adopted: 1)we used yearly governmental data at both catchment and regions scales; 2)we replaced governmental irrigation data by remote sensing-based irrigation estimation. First Order Uncertainty Analysis (FOUA)was performed to characterize the uncertainty associated with the assessment ofWS. Results reveal that theWS at the scale of the catchment increases considerably in recent years, exceeding 50% from2005 and surpassing the 100% threshold in 2015 and 2016 (102%, 108% respectively). The two adopted approaches result in similar WS trends. However, the second approach yields higherWS values compared to the first approach (144% versus 108% in 2016). Themonthly-disaggregatedWSat catchment scale exhibits a similar increasing trend. The highestWSvalues are at the end of the fall and during the summer season,which ismainly due to the increasing demand for irrigation and drinking water. Siliana region is the most affected byWS, while Beja is the least affected. The FOUA shows that the integration of remote sensing-based irrigation data reduces theWS uncertainty.

Water resources management techniques have been evolving over the years, introducing new ways of monitoring and collecting data that improve both the quality and quantity of water-related information. Among them, Citizen Science (CS) has been introduced in the field of environmental monitoring as a novel approach that involves a direct collaboration between citizens, scientists and local authorities. In Tunisia, the lack of reliable hydrological data about rivers' discharge remains a major issue, despite the recent governmental efforts to reinforce the existing official monitoring systems. In this study, we show how this problem can be efficiently addressed using a CS methodology. Citizens at two locations in Tunisia (Slouguia and Medjez-N5) have monitored discharge of the Medjerda river (the most important water resource in the country) using a mobile phone application for a series of hydrological events. Using a Best Linear Unbiased Predictor (BLUP) as a data fusion procedure for combining the various CS measurements, the results show that predicted discharge at both locations is in very good agreement with the reference data collected for the same hydrological events. Based on a variance decomposition, this approach allows us as well to properly assess the respective part of the random errors that are related to the citizens and measuring devices. It is concluded that CS-based discharge data collection is a promising cost-effective way for obtaining reliable and numerous measurements. The monitoring approach based on the use of a mobile phone application is thus quite valuable for complementing the existing Tunisian monitoring system, as well as for empowering local communities. Furthermore, this approach can be applied at larger scales in the country by involving more citizens and adding other sites, which should support the national efforts for better and smarter water resources management.

Water resources management techniques have been evolving over the years, introducing new ways of monitoring and collecting data that improve both the quality and quantity of water-related information. Among them, Citizen Science (CS) has been introduced in the field of environmental monitoring as a novel approach that involves a direct collaboration between citizens, scientists and local authorities. In Tunisia, the lack of reliable hydrological data about rivers' discharge remains a major issue, despite the recent governmental efforts to reinforce the existing official monitoring systems. In this study, we show how this problem can be efficiently addressed using a CS methodology. Citizens at two locations in Tunisia (Slouguia and Medjez-N5) have monitored discharge of the Medjerda river (the most important water resource in the country) using a mobile phone application for a series of hydrological events. Using a Best Linear Unbiased Predictor (BLUP) as a data fusion procedure for combining the various CS measurements, the results show that predicted discharge at both locations is in very good agreement with the reference data collected for the same hydrological events. Based on a variance decomposition, this approach allows us as well to properly assess the respective part of the random errors that are related to the citizens and measuring devices. It is concluded that CS-based discharge data collection is a promising cost-effective way for obtaining reliable and numerous measurements. The monitoring approach based on the use of a mobile phone application is thus quite valuable for complementing the existing Tunisian monitoring system, as well as for empowering local communities. Furthermore, this approach can be applied at larger scales in the country by involving more citizens and adding other sites, which should support the national efforts for better and smarter water resources management.

La cartographie de la vulnérabilité des eaux souterraines à la pollution joue un rôle important dans la mise en oeuvre des politiques environnementales. La vulnérabilité est fortement déterminée par les propriétés du sol qui protège les nappes souterraines. L'archive pédologique belge contient des informations spatialisées sur ces propriétés qui se prêtent d'emblée à une valorisation dans la cartographie de la vulnérabilité. Dans cet article, le rôle des sols dans la caractérisation de la vulnérabilité des eaux souterraines est appréhendé par la notion de la vulnérabilité partielle du sol (VPS). Trois approches sont présentées pour cartographier cette VPS, la première recourt à l'utilisation de la carte pédologique et les deux autres à la base de données des profils pédologiques. Les trois approches sont appliquées à la cartographie de la VPS à la pollution par des produits phytosanitaires dans la région des sables du Bruxellien. Les trois approches donnent lieu aux cartes de VPS qui divergent à l'échelle locale. Quelques explications pour ces divergences sont données, ainsi qu'une méthode pour valider les différentes approches