69 research outputs found
Factors affectingwater drainage long-time series in the salinized low-lying coastal area of Ravenna (Italy)
The low-lying coastal area of Ravenna (North-eastern Italy), like the majority of delta and coastal zones around the world, is affected by groundwater salinization due to natural processes (such as low topography, natural land subsidence, seawater encroachment along estuaries, etc.) and anthropogenic activities (i.e., increased anthropogenic subsidence rate, sea level rise, geofluids extraction, and drainage). Among all factors causing aquifer salinization, water drainage plays an important role in lowering the hydraulic head and favouring saltwater seepage in the Ravenna coastal aquifer. A network of drainage canals and water pumping stations first allowed for the reclamation of the low-lying territory and today are fundamental to keep land and infrastructures dry and maintain effective soil depth for agriculture practices. The aim of this work is to identify and assess factors affecting water drainage long-time series (1971-2017) of the most important mechanical drainage basin in this low-lying coastal area. Statistical analyses of drainage, climate, and land use change datasets help constrain the relative weight of each single factor potentially causing an increase of water drainage through time. The results show that, among these factors, subsidence rates and seepage processes are the most significant. The data trends also indicate that the climate, especially in terms of precipitation amount and extreme events, played no important role during the studied time interval. The process of infiltration soil capacity loss due to urbanization and consequent soil sealing probably has a small secondary effect. Moreover, an increase in pumping through time will exacerbate aquifer salinization and compromise freshwater availability in the coastal area
Assessment of seasonal changes in water chemistry of the ridracoli water reservoir (Italy): Implications for water management
The Ridracoli artificial basin is the main water reservoir of the Emilia-Romagna region (Northeast Italy). The reservoir was made by construction of a dam on the Bidente River in 1982. It is used as the main drinking water supply of the region and for hydropower production. The physical and chemical parameterseters (temperature, pH, electrical conductivity, and dissolved oxygen) of shallow water are continuously monitored whereas vertical depth profiles of water chemical data (major anions and cations, as well as heavy metals) are available on a bimonthly base. The dataset used in this research is related to the years 2015 and 2016. Data show that the reservoir is affected by an alternation of water stratification and mixing processes due to seasonal change in water temperature, density, and the reservoir water level. In late summer and winter months, the water column is stratified with anoxic conditions at the bottom. During the spring, on the other hand, when storage is at its maximum, water recirculation and mixing occur. The reservoir is characterized by a dynamic system in which precipitation, dissolution, and adsorption processes at the bottom affect water quality along the reservoir depth column. The temperature stratification and anoxic conditions at the reservoir bottom influence the concentration and mobility of some heavy metals (i.e., Fe and Mn) and, consequently, the quality of water that reaches the treatment and purification plant. This study is relevant for water resource management of the reservoir. Assessing the seasonal changes in water quality along the reservoir water column depth is fundamental to plan water treatment operations and optimize their costs. The reservoir assessment allows one to identify countermeasures to avoid or overcome the high concentrations of heavy metals and the stratification problem (i.e., artificial mixing of the water column, new water intakes at different depths operating at different times of the year, blowers, etc.)
The Comacchio Lagoon: a naturalistic and historical itinerary
There are few places that, although subjected over the centuries
to massive transformation by man, have been able to maintain
their environmental identity and clearly display what remains,
has been reborn and continues on, both culturally and naturally,
in the collective memory and in the local folklore. Comacchio is
one of these fortunate places.
A wealth of natural, social and economic conditions can now be
found in the Po Delta, which is no wonder, given the richness of
the territory’s millenary history as an ancient thoroughfare of
European civilization, traversed in numerous directions to link
Europe, the Adriatic and the Middle East. Mercantile trading,
military transit, occupations, conquests, and day to day contact
with different cultures and civilizations, have, over the years, left
their mark and given birth to a multiform reality which is rarely
found in similar areas.
From this stems the importance of investigating the area’s
morphology, its naturalistic and environmental value, and its
economy and culture, tracing the different phases and periods
of the territory’s history: from its settlements to its economic
life, from its means of production to its urban planning, and
from its political and social order to its traditions, ways of living
and thinking.
The Comacchio area and the Delta emerge today from a century
old drama of misery and hunger, from which the objective
scarsity of resources and the exasperated exploitation of both
resources and human labour have led too often to a violence of
the natural habitat and have forced the indigenous population
to fi ght for its very survival.
The lagoon museum is the forerunner of a major project aimed
at the Po Delta in Comacchio. Another achievement will soon
be the monographic museum exhibiting the ancient Roman ship
found in 1981 at Valle Ponti lagoon and which will be restored
by the local council, together with regional and national authorities, is preparing to exhibit in Palazzo Bellini, alongside some restored documentary evidence
Reproducing GCHP investments: a common methodology to evaluate the degree of success
Geothermal energy, that is the energy extracted from heat stored in the earth, is one of the most environmentally-friendly and cost-effective energy sources with potential to help mitigate global warming and replace fossil fuels if widely deployed. The IPCC Special Report on Renewable Energy Sources and Climate Change Mitigation (source, IPCC 2010) compares the lifecycle GHG emissions for broad categories of electricity generation technologies and highlights, among other things, the huge potential of the geothermal energy in reducing the GHG emissions. Recent technological progress, the variability of the cost, the difficulty of oil and gas supply from foreign countries and the need to reduce the use of fossil fuels to cut pollution have made the exploitation of geothermal energy, especially low-enthalpy power generation utilizing GCHP (Ground Coupled Heat Pumps), an attractive and viable energy alternative. Advances in technology have dramatically expanded the range and size of viable resources, especially for applications such as home heating and cooling, opening up the potential for widespread exploitation such as geothermal energy applications to curb energy consumption of industry and small and medium enterprises, that are the most exposed to the energy price fluctuation. Therefore, as stressed by the UE Energy Roadmap to 2050, a broad diffusion of this type of energy source could bring a concrete contribution to decarbonise the European economy and meet the targets of reducing the GHG emissions by 20% by 2020 and by 80-95% by 2050 (compared to 1990 levels). Nevertheless, the European Commission points out that this sector is not doing enough to exploit the potential of renewable energy sources (RES), emphasising that increased electricity and heat generation from geothermal resources will partially avoid the need for new fossil fuel power generation. Geothermal heating and cooling still need research and development over the next few years, notably to improve the efficiency of the systems and to decrease installation and operational costs. However, the main barrier to increased geothermal deployment is a lack of appropriate financial incentives and legislation (particularly relevant to the new build market where house-builders must install a certain number of energy efficiency and RES measures to obtain planning permission) as well as on both EU and local level. Hence, the European Commission, in the Renewable Energy Road Map, encourages member states and their local authorities to apply and implement concrete measures in order to improve energy production and distribution, to facilitate financing and investment in the green sector, and to encourage and consolidate rational energy consumption behaviour, with the final aim of making Europe the world leader in renewable energy and low-carbon technologies. GEO.POWER is set against this background. The partnership, composed of twelve partners from nine EU countries under the coordination of the Province of Ferrara (IT), being aware of the energy challenges mentioned above, has implemented a two-year capitalisation project under the INTERREG IVC programme aiming at evaluating the reproducibility of some of the most outstanding examples of best practice currently existing in Europe for the utilisation of low-enthalpy energy, mainly related to the so called ground-coupled heat pumps (GCHP). The project objectives are (a) to exchange the partners’ own experiences on geothermal energy production through GCHP to support the weakest regions to implement large scale investments; (b) to fill the legislation gaps in the geothermal energy sector to address a favourable (political and normative) context to attract investment; (c) to profile an integrated package of final incentives and technical measures in the frame of the forthcoming Regional Operational Programme in the period post 2013, where large amount of funds (currently under negotiations) will be dedicated to co-finance energy efficiency and carbon-free energy projects. In GEO.POWER the necessary implementation measures are outlined in one action plan per project area, to be later on financed through regional and national mainstream programmes or future regional financial instruments. The action plan consists of a local strategy (covering several aspects such as the technological transfer, the definition of subsidy schemes and the training of personnel) for the large scale introduction of GCHP
The Need for Better 3D Conceptual Models of Aquifers in the Murray-Darling Basin.
There are many challenges ahead as we learn how to better manage the allocation and movement of water throughout the Murray-Darling Basin (MDB). A significant step towards better management is acknowledging the complexity of the alluvial aquifers and working out how to capture this complexity in our water management models.
The New South Wales State government has extensive borehole data records. Driller logs can be interpolated to yield a comprehensive 3D faciesmodel. Geostatisticalmethods are often used for modelling facies(Deutsch 2002). The major steps are 1) establish large scale geological structures, 2) within each zone use object-based simulation to model palaeochannels(Keogh et al. 2007, Pyrczet al. 2009) 3) populate each faciesusing an appropriate geostatisticalor nonparametric classification technique (Dubois et al. 2007, Tartakovskyet al. 2007). Research within the NCGRT will be validating the appropriateness of existing algorithms and developing new methods for predicting faciesat locations where samples have not been taken.
There are many advanced 3D geological modelling packages on the market. However, the algorithms behind many of the processes are not public, and the direction of development is driven by commercial interests. Students and researchers need an accessible 3D geological modelling environment to allow for the evolution of ideas and processes. Many of the pieces exist. There are scripting languages like Python, Maple, Mathematica, and Matlabthat have good database connectivity and come with high quality 3D visualisation tools. These scripting environments allow for the rapid construction of 3D geological structural models , and are ideal nonparametric modelling environments. Stochastic modelling of the faciescan be done using GSLIB or SGEMS. These models can then be imported into MODFLOW or FEFLOW. The skills required to use all these components at the level necessary to model our catchments has traditionally not been widely integrated into our University courses. These skills will be taught through the National Centre for Groundwater Research and Training.
In Australia, the application of 3D conceptual aquifer models has been limited, compared to the level of adoption throughout Europe and North America. Through the development of accessible software and procedural documents it is hoped that the use of 3D geological conceptual models will be common for:
- data integration; - conveying the complexity of alluvial aquifer systems throughout the MDB and other alluvial aquifers throughout Australia; - characterising contaminated sites; - developing framework models for input into groundwater flow modelling packages, and - communicating groundwater processes to all stakeholders.
For the size of the country and the number of groundwater management issues Australia is confronting there are too few hydrogeologists. Through the new ARC/NWC co-funded National Centre for Groundwater Research and Training we aim to increase the number practitioners with the skills required to analyse, communicate and manage our groundwater resources. Providing accessible software is critical for the universal adoption and practice of constructing 3D geological conceptual models to advance the management of Australia’s aquifers
Macquarie Catchment Groundwater Hydrographs
The hydrogeology of the Macquarie Catchment has been studied extensively in the past 20 years, but there are still many gaps in our understanding of the groundwater systems and river-aquifer interactions. These gaps in our knowledge limit our capacity to manage water resources throughout the catchment. This document captures our current understanding of the hydrogeology of the catchment and provides a multidimensional spatial analysis of the groundwater standing water level data. Based on the finding recommendations for further research are then presented.
Abstraction of groundwater for the purposes of irrigating cotton and other crops started in the Macquarie Catchment in 1967, and expanded until the turn of the century. To monitor the impact of groundwater usage NSW State water management departments installed monitoring bores in the zones with significant groundwater usage. The groundwater monitoring data are publicly available on the Pinneena Groundwater Monitoring CD. This report presents all the hydrographs for the Macquarie Catchment, and examines the spatial and temporal trends displayed in these data. The primary goal of this project was to provide a graph of all the groundwater hydrographs in the catchment. A printout of every hydrograph within the Macquarie catchment is presented in the Appendix.
Through the implementation of water sharing plans there have been changes to groundwater allocations. At some locations there has been a reduction in the water allocated per share, with the aim of improving the long term viability of the groundwater resource for all users and the environment. The groundwater hydrographs provide a record of baseline conditions and can be used to assess the impact of variations in allocation and guide future management decisions.
Almost 40 years of groundwater hydrograph records enable long term groundwater level trends to be analysed throughout the alluvial regions of the catchment. Groundwater head change over long and short periods of time are analysed using traditional hydrograph plots and 3D plots to show the yearly and interdecadal impacts of groundwater extractions. The groundwater hydrograph data are interpreted in the context of existing geological knowledge, streamflow, rainfall and groundwater usage data.
Within the Macquarie Catchment a unique balanced needs to be achieved in the way water is managed if urban centres and farms dependent on the water are to prosper, while maintaining important wetlands at the end of the catchment. The Macquarie River flows northwest from the head waters on the western side of the Great Dividing Range just south of Bathurst, to join the Barwon River west of Brewarrina. The southern portion of the Macquarie River is highly regulated by Burrendong and Windamere Dams and by a series of weirs, bypass canals and irrigation channels that assist the diversion and abstraction of water for irrigation, industrial and domestic purposes. The major irrigation district is north of Narromine and south of the Macquarie Marshes on the fertile soils of the floodplain. This flood plain overlies up to 150 m of valley-fill sediments which lie within the Macquarie River palaeovalley. It is the fresh groundwater within these sediments that is used for irrigation. The Macquarie Marshes just north of the irrigation district are a large and diverse system of semi-permanent freshwater wetlands created by irregular flooding of the flat lands adjacent to the river and are an important ecological habitat.
This study identifies zones along the river where aquifers within the sediments that fill the deep palaeovalley are locally hydraulically connected to the river, and zones where the deep aquifers are disconnected from the shallow aquifers and do not receive direct river recharge. The largest zone of aquifer depletion is west of Narromine. This zone requires further extensive hydrogeological and water chemistry investigations to better understand the recharge pathways. If the management goal is to reduce the decline in the groundwater head, then this region may require managed aquifer recharge.
North and west of Narromine there are zones of local rising watertable in the upper unconfined aquifer due to irrigation recharge (deep drainage). Further research is required to determine if this will result in future soil and water quality problems.
Based on these findings it is suggested that a detailed 3D lithofacies model needs to be constructed for the Lower Macquarie Catchment. This 3D model could then guide the construction of a coupled surface and sub-surface flow model. Also required is an extensive groundwater chemical investigation (with a focus on dating the ages of the groundwater zones) and coupled river and aquifer flow modelling, linked to the water chemistry investigations. The results of these investigations should help to better inform water management decisions
Functional Programming Algorithms for Constructing 3D Geological Models
Three dimensional (3D) geological models are commonly used in the petroleum, mining and groundwater sectors for examining structural relationships, volumes and the distribution of properties. These models are built from irregularly spaced data that define fault surfaces or the top, bottom and sides of structural units (formations, period boundaries etc.). Geological data can be collated as lists, making these data amenable to
manipulation using functional programming algorithms. Scripts written in functional languages are concise and resemble more closely traditional mathematical notation (Goldberg 1996, Hudak 1989). When the functional programming style is used in a
symbolic mathematical program with 3D graphics short scripts can be written for constructing 3D geological models. When teaching the fundamentals of 3D geological model construction symbolic mathematical programs allow students with little or no programming experience to learn how to sort the data, interpolate/extrapolate surfaces over the domain, and build 3D
geological models using a set of logical expressions that dictate how the surfaces intersect to represent geological units. Exposing the students to the mathematics and scripting steps provides insights into the exactness and limitations of the models and introduces them to an open ended modelling environment.
Two algorithms are presented. The first script projects point measurements (x, y, z, inclination, azimuth) from field or map data along an inclined line to extend the data to form a series of points that define a surface which can subsequently be gridded. The second script performs inverse distance gridding (Yamamoto 1998). These scripts are written using the symbolic programming and visualisation software Mathematica (Wolfram Research, Inc., 2008), which is probably the most widely used functional
programming language (Hinsen 2009). The application of the algorithms is demonstrated by constructing a 3D geological
structural model of the Maules Creek catchment in NSW, Australia. The data sets consist of a digital elevation model (DEM), borehole bedrock picks, period geological boundaries digitised from the 1:250000 geological map (the top of the Permian, and Triassic, and the digitised limit of the Tertiary basalt . Inclination and azimuth details were inferred from the geological map. Elevations were assigned to the digitised map values by defining an approximate function for the DEM (using the
Mathematica function Interpolation) and then applying this function to the list of points. This process is described in more detail below
The Need for Better 3D Conceptual Models of Aquifers in the Murray-Darling Basin.
There are many challenges ahead as we learn how to better manage the allocation and movement of water throughout the Murray-Darling Basin (MDB). A significant step towards better management is acknowledging the complexity of the alluvial aquifers and working out how to capture this complexity in our water management models. The New South Wales State government has extensive borehole data records. Driller logs can be interpolated to yield a comprehensive 3D faciesmodel. Geostatisticalmethods are often used for modelling facies(Deutsch 2002). The major steps are 1) establish large scale geological structures, 2) within each zone use object-based simulation to model palaeochannels(Keogh et al. 2007, Pyrczet al. 2009) 3) populate each faciesusing an appropriate geostatisticalor nonparametric classification technique (Dubois et al. 2007, Tartakovskyet al. 2007). Research within the NCGRT will be validating the appropriateness of existing algorithms and developing new methods for predicting faciesat locations where samples have not been taken. There are many advanced 3D geological modelling packages on the market. However, the algorithms behind many of the processes are not public, and the direction of development is driven by commercial interests. Students and researchers need an accessible 3D geological modelling environment to allow for the evolution of ideas and processes. Many of the pieces exist. There are scripting languages like Python, Maple, Mathematica, and Matlabthat have good database connectivity and come with high quality 3D visualisation tools. These scripting environments allow for the rapid construction of 3D geological structural models , and are ideal nonparametric modelling environments. Stochastic modelling of the faciescan be done using GSLIB or SGEMS. These models can then be imported into MODFLOW or FEFLOW. The skills required to use all these components at the level necessary to model our catchments has traditionally not been widely integrated into our University courses. These skills will be taught through the National Centre for Groundwater Research and Training. In Australia, the application of 3D conceptual aquifer models has been limited, compared to the level of adoption throughout Europe and North America. Through the development of accessible software and procedural documents it is hoped that the use of 3D geological conceptual models will be common for: - data integration; - conveying the complexity of alluvial aquifer systems throughout the MDB and other alluvial aquifers throughout Australia; - characterising contaminated sites; - developing framework models for input into groundwater flow modelling packages, and - communicating groundwater processes to all stakeholders. For the size of the country and the number of groundwater management issues Australia is confronting there are too few hydrogeologists. Through the new ARC/NWC co-funded National Centre for Groundwater Research and Training we aim to increase the number practitioners with the skills required to analyse, communicate and manage our groundwater resources. Providing accessible software is critical for the universal adoption and practice of constructing 3D geological conceptual models to advance the management of Australia’s aquifers
Importing and separating a Digital Elevation Model (DEM) for near surface geological models in EarthVision.
The top surface of 3D Geological Models that represent the near surface geology in catchments is the surface topography. Data that define the topographic surface can be obtained from many sources including satellite, land-based and airborne geophysical surveys, geological field mapping and borehole logging. The most common form of topographic data used in spatial data analysis are the freely available Digital Elevation Models (DEMs).
Often sediment filled valleys are surrounded by mountains with exposed rock outcrops. In this situation the DEM defines the top of the rock surface and the top of the sediments. When building a 3D EarthVision geological model of a catchment the DEM needs to be separated into the two domains.
This manual details how this can be achieved in EarthVision.
If the DEM data are in a GIS raster format then the data need to be preprocessed in a GIS package before being imported into EarthVision. For this manual the DEM is firstly imported into ArcGIS, cleaned, trimmed and then exported into a format compatible for EarthVision.
The data used for this example are from the Maules Creek catchment located in the state of New South Wales, in Australia. The methodology developed for this case study can be successfully applied on any area of steep rocky mountains surrounded by flat alluvial plains. In these locations the gradient of the DEM data is sufficient for sorting the data into regions of rock outcrop and alluvial plains. High gradient (the rock outcrop) are sorted from the flat areas (the alluvial sediments) by calculating the partial differential in X and Y directions.
In EarthVision there is a Slope Grid program. Using this program to separate low gradient alluvial areas from step rocky areas may be appropriate in some catchments. The process detailed below although based on examining the slope of the surface, has some subtle variations compared to using the Slope Grid program and yields a slightly different degree of separation. The major differences are adding the X and Y partial differential grids and then filtering this output
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