CIGR Newsletter No 43

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NEWS FROM THE PRESIDIUM

AGRICULTURAL ENGINEERING
IN THE 21ST CENTURY
The Role of CIGR

by
Prof. Dr. B. A. Stout, PE
Incoming President, CIGR

This is an exciting time to be an agricultural engineer. Our profession is addressing great challenges facing humanity such as ensuring an adequate and safe food supply for an expanding world population; managing the world’s vital natural resources -water, soil, air, and energy; and protecting the environment. Agricultural Engineering is a vital discipline supporting world agriculture.

The world has become very small indeed. Jet planes carry people and products from one continent to another in a matter of hours. Hundreds of companies that employ agricultural and food engineers operate on a broad international scale involving different cultures and languages. Let’s consider just two examples:

Numerous other examples could be cited. Globalisation of business is a reality, not a future dream.

We live in the information age in which rapid expansion of electronic communications is shrinking the world even further. In the past telephone, telex and fax technologies provided major communications links among countries, but were limited because of the cost and occasional lack of reliability. Today E-mail provides much of the world with rapid and inexpensive written communications. The World Wide Web (WWW) contains a vast amount of information and highly sophisticated search devices that enable the user to focus quickly on the specific information desired. It is true that not everyone is connected to the WWW, but the system is growing rapidly. More and more agricultural engineers around the world have access to E-mail and the WWW. Surely, as we look toward the 21st century, electronic information delivery will become the dominate form of communications.

CIGR is moving rapidly in the field of electronic communications. For several years CIGR has had a home page (http://wwworg.nlh.no/CIGR/) which provides information about CIGR, its goals, organisation and activities, such as the electronic calendar of events, handbook and newsletter.

Two new and exciting proposals to expand CIGR electronic communications have been approved. They are the CIGR electronic journal and the CIGR/FAO global E-mail network.

CIGR E-Journal

The E-Journal will provide a means for communication and exchange of research results and other more general information among agricultural engineers and others interested in agricultural engineering subjects around the world. It will provide an international forum for the scientific discussion of techniques and approaches leading to a higher degree of efficiency in agricultural production, the responsible use of natural resources, a cleaner environment, greater sustainability, value-added processing and other subjects of interest to agricultural engineers. It will also include economic considerations and discussion of policies of interest to agricultural engineers and other related disciplines.

The E-Journal will operate in a manner similar to a conventional paper journal. The Editor-in-Chief is Dr. George Sabbagh, Professor of Agricultural Engineering, Texas A & M University. He will be responsible for the overall operation of the journal. An Editorial Board will be responsible for reviewing manuscripts and maintaining high quality standards.

This new electronic journal will provide an inexpensive outlet for authors and an equally inexpensive source of information for anyone interested in agricultural engineering topics. For further details contact Dr. George Sabbagh (ejournal@cigr.agen.tamu.edu).

CIGR/FAO Global E-mail Network

A series of list-serves organised by subject matter (e.g. soil and water engineering, processing, mechanisation, etc.) will allow agricultural engineers from around the world to exchange information. These list-serves make e-mail conferencing a practical reality thus reducing the need for so many expensive conferences. Parts of the network already exist and other parts are being developed. For further details contact Theodor.Friedrich@FAO.org or Peter Schulze Lammers, Secretary General of CIGR at ulp81a@ibm.rhrz.uni-bonn.de

Handbook of Agricultural Engineering

Several hundred chapter authors, experts from around the world, have completed their manuscripts. Following peer review, the 1400 page, 5-volume handbook series will be published by ASAE in late 1998 or 1999 in traditional book form and also as a compact disk. The CD will allow electronic searching and will facilitate finding the specific information needed at the moment.

CIGR is a forward-looking global network of agricultural engineers. The future in the 21st century is exciting. We must work together to strengthen the national and regional societies. We must focus our resources on the most critical issues facing the global society. We must communicate more effectively with our scientific and engineering peers as well as the general public. We must effectively articulate the vital nature of our work in terms of social and economic benefits.

We must seek to become full-fledged members of the team of policy makers and budget planners who decide where public R and D funds are directed. These are my goals as Incoming President. I invite you to join me to expand the CIGR global network and to make it more effective. Let’s work together as national societies, regional societies and individuals to achieve these goals as we begin the 21st century.

Incoming President address, XIIIth World Congress, Rabat, Morocco.

CIGR General Secretariat moves to a new location.

Effective March 1, 1998 the General Secretariat of CIGR moved from the Research Station of Agricultural Engineering in Merelbeke, Belgium to the Institut für Landtechnik, Universität Bonn, Germany.

During the last meeting of CIGR’s General Assembly in Rabat, Morocco, on the occasion of the XIIIth World Congress of CIGR Prof. Dr. Ing. Peter Schulze Lammers was elected Secretary General of CIGR for the period 1998-2002 to succeed Prof. Dr. Ir. Jan Daelemans who decided to withdraw in view of his retirement as Director of the Research Station of Agricultural Engineering in 2000.

Dr. Jan Daelemans was elected Secretary General of CIGR during the World Congress of CIGR in 1989 in Dublin, Ireland and held that position from 1990 till 1998. As President of CIGR was then elected Prof. P. McNulty from Dublin University, Ireland. Jan Daelemans succeeded Ir. Michel Carlier from France who was in office for more than a quarter of a century.

Prof. Jan Daelemans receives the Certificate of Appreciation for his dedication to CIGR and the agricultural engineering profession during the past ten years out of the hands of Mr. R. Fridley, President of ASAE. From l. to r.: Prof. E. Berge, Past President of CIGR, President of ASAE Mr. R. Fridley, Prof. J. Daelemans and Prof. O. Kitani, President of CIGR.

In the period 1989-1998 CIGR has seen some drastic changes. It proceeded from an almost exclusively European organisation with a few links outside Europe to a worldwide networking organisation under the impulse of Prof. Pellizzi, now Honorary President of CIGR.

The existence of a well-structured American Society viz. ASAE and the emergence of other Regional Societies such as EurAgEng in Europe, AAAE in Asia, SEASAE in Africa and ALIA in Latin America and the Caribbean Area opened an opportunity for CIGR to step forward and act as a networking agency.

During the office of Dr. Jan Daelemans there were two successful CIGR Congresses viz. in Milan, Italy in 1994 and this year in Rabat, Morocco, the latter the first congress in Africa and the second outside Europe. The cooperation between CIGR and many countries both inside and outside Europe was intensified.

The publication of a Newsletter, initiated by Michel Carlier was continued and gradually extended. In April 1990 issue N° 10 appeared, edited by Frank Lunn, secretary of CIGR from 1990 till 1998. Since then, Frank Lunn continued to edit the Newsletter quarterly and in October 1993 a French edition was added to it, viz. Bulletin de la CIGR (issue N° 24), with the kind help of Ir. Souty, President of AFGR and Mrs. Odette Manchon, both of the French Ministry of Agriculture and Fisheries. Mrs. Odette Manchon was instrumental for the translation of the Newsletter into French. This cooperation has continued until to date.

Under the impulse of Prof. O. Kitani, CIGR is currently finalising a treatise on agricultural engineering viz. the Handbook of Agricultural Engineering, which is due to appear shortly. It is the result of a massive effort by a large group of scientists from all over the world and with the assistance of ASAE who kindly offered to publish this work. It is the intention to make this handbook available to many libraries in developing countries.

The introduction of e-mail and other Internet applications has greatly enhanced communication among the members of the Presidium, the Executive Board and members in general. In 1996 with the help of Prof. Berge, then President of CIGR and Mr. Geir Tutturen of the Agricultural University of Norway, CIGR was given its own website on the Internet. The Calendar of Events was also a result of the cooperation between the General Secretariat and Mr. Geir Tutturen. A Webmaster Working Group is currently working on other new interesting additions to our website. An e-journal on agricultural engineering is the latest addition to CIGR services and has been developed and realised by Prof. Stout, Incoming President of CIGR and Texas A & M University.

Financially, CIGR received a strong stimulus in the past years from the Japanese Science Council and from Mr. Kishida, President and Chief Editor of AMA. Also Kverneland of Norway contributed financially.

Correspondence with members, member associations, international organisations and other organisations has increased dramatically since the mid nineties.

Doing all these tasks would have been impossible without the help of so many people who have not hesitated to spend some time assisting us in this mission. Mentioning all names would be impossible but we would like to express our gratitude to the members and past members of the Presidium, the members and past members of the Executive Board, the Chairmen and past Chairmen of the Sections, the members and past members of the Section Boards, the members and past members of the Working Groups, and so many individuals who have all assisted us in the past. A special word of thanks goes also to the Belgian Ministry of Small Enterprises, Traders and Agriculture who have given us the possibilities and support to fulfil this mission and to the many colleagues at the Research Station of Agricultural Engineering who were so kind to offer us some help when needed.

We wish our successors in Bonn good luck with their new mission and we wish CIGR a successful future.

Prof. Dr. Ir. J. Daelemans, Secretary General 1990-1998
F. Lunn, Secretary 1990-1998.

CIGR ELECTRONIC JOURNAL

(Revised April 30, 1998)

Publication of research results and exchange of information is central to any discipline. Agricultural engineers have the opportunity to publish in several journals dedicated to the profession and also in numerous peripheral journals, serving other disciplines. As CIGR expands its horizons to more and more countries around the world, it can serve the international membership by providing a low cost, widely available journal.

Recent advances in electronic publishing provide a suitable mechanism for widespread dissemination of information. Thousands of journals are now being published electronically and are available on the World Wide Web (WWW). The technology to publish on the WWW is moving ahead rapidly. More and more agricultural engineers around the world have access to the WWW.

Approval by CIGR

The CIGR Executive Board approved the e-journal at its meeting in Rabat, Morocco on February 2, 1998 and authorised Dr Stout and Dr Sabbagh to proceed with implementation.

Operations

The CIGR e-journal will operate in a manner similar to a conventional paper journal. The Editor-in-Chief (EiC) is Dr. George Sabbagh, Agricultural Engineering Department, Texas A&M University, who will be responsible for overall operation of the journal. Appointments to the Editorial Board for an initial three-year period will be made jointly by Dr. Sabbagh and Dr. Stout. The Editorial Board will be responsible for reviewing manuscripts and maintaining high quality standards. The EiC will report to the CIGR President through the Executive Board. The CIGR E-Journal will be linked to the CIGR Website (and thereby to ASAE, EurAgEng, AAAE, etc.) for easy access.

Web Site

A home page has been set up at the following address:

http://www.agen.tamu.edu/cigr/

Detailed information is given about the e-journal and its policies. Authors should submit manuscript to

ejournal@cigr.agen.tamu.edu

A submission form is included in the web site and must be completed by authors when their manuscript is submitted. If the manuscript has been submitted to another journal or has been presented as a paper at another society meeting, a clearance will be required before it will be considered for publication in the CIGR e-journal.

Mission Statement

The CIGR e-journal will provide a means for communication and exchange of research results and other more general information among agricultural engineers and others interested in agricultural engineering subjects around the world. It will provide an international forum for the scientific discussion of techniques and approaches leading to a higher degree of efficiency in agricultural production, the responsible use of natural resources, a cleaner environment, greater sustainability, value-added processing and other subjects of interest to agricultural engineers. It will also include economic considerations and policy issues of interest to agricultural engineers and other disciplines. Categories for consideration by the Editorial Board will include:

Language

The working language of CIGR is English and thus, the language of the CIGR e-journal will be English.

Editorial Board

A rather large Editorial Board will ensure broad geographic and subject matter representation. It will also reduce the workload of members so that no more than 2 or 3 manuscripts will be reviewed by an individual in a given year. The goal will be rapid review and processing of manuscripts to facilitate timely dissemination of information. Some criteria for selection of Editorial Board members are:

Each of the six CIGR section chairs has been asked to nominate 4 or 5 individuals to serve for an initial three-year period on the Editorial Board. Other appointments will be made as necessary to round out the group geographically and in terms of subject matter coverage.

Computer Facilities

For an initial period of 3-4 years the computer facilities of Texas A&M University will be used at no cost to CIGR.

Archiving

Papers will be put on the WWW under the CIGR home page immediately after the peer review process is completed and the necessary modifications are made to the satisfaction of the EiC. At the end of each year, all papers will be printed, bound and sent to several prominent libraries for permanent archiving. A copy will be kept at the CIGR General Secretariat where requests for reprints will be handled. Perhaps reprints will not be an issue since most everyone can print their own copies as they wish.

Financial Aspects

Given that the Editor-in-Chief and the Editorial Board will be non-paid volunteers, the cost of operating this electronic journal will be minimal. The primary costs will be to support an assistant to the EiC, binding of archival copies and postage.

A budget of $ 5,000 US per year is proposed with $ 2,000 coming from the CIGR general budget and $ 3,000 solicited in the form of gifts and corporate sponsorships.

Initially, to encourage submission of manuscripts, publication in the CIGR e-journal will be without charge to the author. As the e-journal gains status and recognition, in the future the Executive Board may impose modest *page charges* in order to cover operating costs.

Availability

Initially, anyone may submit a manuscript for consideration by the Editorial Board, regardless of whether or not the individual is a CIGR member or is from a CIGR member society. Again, the Executive Board may review this policy after an initial start-up period.

Availability to readers will be unrestricted. Mechanisms to restrict access to e-journals exist, but are not considered to be in the interest of CIGR’s desire for widespread dissemination of information.

Guide for Authors

ASAE guidelines for authors will be used initially and may be modified in the future as we gain experience. Initial thinking is that manuscripts will be limited to a maximum of 8 pages. Authors will be advised to restrict graphics and photographs to the bare essentials because of the large amount of memory required.

Number of Manuscripts Published per Year

This depends on the number submitted and approved by the peer review process of the Editorial Board. We need to work diligently to advertise the CIGR e-journal and to encourage submission of quality manuscripts.

Timeliness

The goal is to complete the initial review process within one month after the author submits the manuscript. Author modifications will require additional time.

Quality

Quality is critical. If this e-journal is to succeed over the long term, we must establish a reputation as a quality journal equal to the best in the agricultural engineering field. Quality control is the responsibility of the Editor-in-Chief and the Editorial Board.

George Sabbagh, Bill Stout,
Editor-in-Chief President CIGR
1999 / 2000

NEWS FROM THE SECTIONS AND WORKING GROUPS

CIGR-WG1 and EurAgEng-SIG12 "Harmonisation of Agricultural Engineering University Curricula" Progress Report

During the XIIIth CIGR Congress in February 1998 in Rabat, Morocco, CIGR Working Group 1 (WG1) and EurAgEng Special Interest Group 12 (SIG12) on "Harmonisation of Agricultural Engineering University Curricula" held a second seminar on updating the CIGR WG Report No. 2 "The University Structure and Curricula on Agricultural Engineering - An Overview of 25 Countries" published in 1994. Prof. P. Febo, Chairman of WG1 and SIG12, chaired the meeting. The participants reviewed the work progress since last seminar held in Madrid during AgEng’96, expressed their support and co-operation for the work and discussed the financial situation on the publication of the new edition of the report. It was realised that the new edition of the report would provide good opportunity for promoting and publicising universities and agricultural engineering curricula.

The updating work of the WG Report No. 2 has been going smoothly. In November 1997, Dr. Da-Wen Sun (Secretary) wrote to 64 experts from Argentina, Belgium, Brazil, Canada, China, the Czech Republic, Denmark, Egypt, Finland, France, Germany, Greece, Hungary, Japan, Jordan, the Netherlands, Norway, Portugal, Spain, UK and USA, requesting for updating their country entries in the WG Report No. 2, and from Australia, Austria, Chile, Colombia, Ghana, India, Israel, Korea, Malaysia, Mexico, Morocco, New Zealand, Nigeria, Poland, Russia, Sudan, South Africa, Sweden, Switzerland, Taiwan, Tanzania, Thailand, Turkey, United Arab Emirates, Venezuela and Zimbabwe, asking for supplying information on the structure of their universities and curricula in agricultural engineering, for inclusion in the new edition of the report. Up to now, Dr. Sun has received replies from most of the experts. Prof. Febo and Dr. Sun would like to express their sincere thanks to these people. However, some experts only sent back the questionnaire without detailed information as required. With only the questionnaire, it is impossible to compile a complete entry for that country. Therefore, it is necessary to supply Dr. Sun the remaining part of the information. Some countries may not be included in the report because replies have not yet been received. However, they are asked to reply to Dr. Sun as soon as possible.

It is important to publish the report when it is finished. CIGR has expressed its difficulty in providing the financial support for the publication. Under this circumstance, Prof. Febo has written to various organisations for this matter. FAO has expressed its interest in the publication. This will be discussed during the next meeting.

The next meeting of WG1 and SIG12 will be held in Oslo during AgEng’98. Anyone who has interest in joining the activity is invited to attend the meeting.

For further information and offers of collaboration please contact:

Prof. Pierluigi Febo, Chairman of WG 1 & SIG 12, Dept. I. T. A. F., Viale delle Scienze, 13, I 90128 Palermo, Italy.

Fax: +39-91-484035; E-mail: pierfebo@unipa.it

or Dr. Da-Wen Sun, Secretary of WG1 & SIG12, Department of Agricultural and Food Engineering, University College Dublin, Earlsfort Terrace, Dublin 2, Ireland

Fax: +353-1-4752119 E-mail: dawen.sun@ucd.ie

Website: http://www.ucd.ie/~food/sun.html

NEWS FROM REGIONAL AND NATIONAL SOCIETIES

EurAgEng SIG on Soil and Water:
Policy on Groundwater Engineering

Groundwater engineering plays a role of paramount importance in the research and development policy of the Group.

It is understood that water resource management should preserve or enhance the buffering capacity of the environment against unexpected shocks or negative long-term trends. As the carrying capacity of the environment is increasingly stressed, due to the growing need of the population and improper use of the resources, the vulnerability of the environment also increases. In this context, mismanagement of water resources with only lip service being paid to the environment has led to water scarcity and water pollution, which threaten food security and human life quality.

Taking proper regard of this unsustainable trend of water usage, the UN General Assembly Special Session (the Rio Plus Five), in June 1997, decided to make water resource management the main theme for the Sustainable Development Committee in 1998.

Although most countries rely predominantly upon surface water, there are many regions of the world, particularly in the arid and semiarid zones, where groundwater is the major, if not the only source of water for agricultural, civil and industrial purposes.

Whereas two decades ago the priority in groundwater engineering was directed towards methods of exploration and exploitation, the current emphasis lies within the long-term sustainability of the resources with respect to both quantity and quality. The challenges nowadays facing groundwater engineers and planners are focusing on the study of groundwater systems with the objective that harmful depletion of this resource is prevented and pollution is controlled.

The last decades had witnessed many cases where ground-water level declines or groundwater pollution had serious negative impacts on public health, national and regional economy and on the natural environment. Therefore, protection and sustainable development of the groundwater resources are mandatory in framing solutions to this kind of problem.

On the one hand, knowledge of the spatial and temporal characteristics of the aquifers provides the basis for such sustainable development and environmentally sound planning of groundwater resources. On the other hand, there is no question that models are and will become in the future one of the most important and widespread tools in the management of long-term environmental problems.

They can serve to formalise scientific understanding, to integrate the various components and processes that make up the whole groundwater system, as a bridge to communicate findings between scientists and policy makers (or the public), as a basis for hypothetical experiments of different scenarios of the future, and to integrate sound planning management strategies and economy by permitting cost-benefit analyses and finding optimal solutions.

The usefulness of predictive simulations obtained by groundwater models is often hampered by the inability to indicate and preferably quantify the reliability of model results. Uncertainty in model predictions primarily stems from a number of errors related to the model formulation, such as:

-inadequate concept and description of processes and interactions
-inadequate description of spatial and temporal variability
-inadequate description of the state of system (geometry, initial and boundary conditions, system stresses)
-incorrect parameter values and improper specification of error bounds.

All this leads to the fact that, in most cases, the efficiency of a model decreases rather than increases as a function of adding too many variables and processes. The outcome is that planning based on mathematical forecasts can be reasonably accurate during relatively stable time periods. But precisely for that reason, models will fail when they are most needed: in anticipating fundamental changes that require a new paradigm in planning for the future.

The idea of transparency appears critically important to the ultimate success and acceptance of models as credible scientific tools. We see the critical issue to be how to keep models transparent enough so that they remain comprehensible to decision-makers as well as to the scientific community. Therefore, there is a critical need for models to set clear goals and to focus only on the minimum set of fundamental processes that are needed to reach the stated goal.

In recent years significant research has been carried out resulting in a variety of approaches that can be used to incorporate the information about the above-mentioned errors into the modelling process and to establish the level of uncertainty in model-based decision-making. One of these approaches is the so-called scenario approach, which offers alternative method for managing an uncertain future. Scenarios are the bridges between facts and perceptions. Their role is to enhance a decision-maker’s understanding of the future by providing perceptions of alternative future environments against which decisions can be tested. The goal is not to predict the future, but rather to learn to live with uncertainty, to factor it into the decision process and to improve the quality of thinking among decision-makers.

Advocating such an approach in no way reduces the value of modelling. On the contrary, the complexity of the real world is such that without some assistance in organising this complexity, policy makers are increasingly helpless and are forced to make decisions without any real idea of the consequences. The distinction, however, is that the models must be judged not by the criterion of how accurately they can reveal actual future trajectories; rather, they should be judged by how useful they are in enhancing the decision maker’s and scientific community’s knowledge and understanding by exploring the dynamic consequences of some of the complex assumptions.

Anyway, one of the great challenges for future groundwater modelling is the development of ways by which models can explicitly display the degree of overall model uncertainty that is caused by the aggregate uncertainty of internal components. The exclusion of a parameter can be a way of testing whether the parameter indeed is a key driving process in a model. In many cases funds are available for the construction of models, but not for collecting the empirical data that are needed for critical tests of how well the model works. One solution is for the modellers to more actively build partnerships or bridges with other research groups.

We believe that the following bridges need to be built between the groundwater modelling community and other communities.

Bridge between physical, chemical and biological processes

The first step in groundwater degradation assessment is to identify potential contaminant sources.

As urbanisation and industrialisation have expanded, so chemical compounds have made their way to aquifers. Moreover, agricultural practices generate non-point contaminants, which put the groundwater resources at high risk.

From a scientific point of view the relationships between soil-water-biosphere-atmosphere have to be analysed in more detail to properly assess groundwater vulnerability. Knowledge on the interactions, feedback, biochemical and hydrochemical processes occurring in the porous media and particularly in the unsaturated zone, is far from sufficient in many key areas. The lack of progress in modelling biological and ecological processes may be due to inherent differences with the biological community. A key question that currently limits progress in this field is: how can groundwater modellers better develop more robust and more generally applicable biological models or sub-models?

Bridge to managers and policy makers

There is an urgent need to foster a dialog between ground-water engineers and decision-makers. The following key questions should be answered:

-What do managers and policy makers need from modellers?
-What levels of uncertainty are acceptable?
-Are pilot projects and associated models a good way to build a better credibility for models?

Turning back to vulnerability, aquifer pollution is a key issue in the Group’s policy on groundwater engineering.

It is well known that degradation of subsurface water resources poses serious public health problems worldwide. In order to logically evaluate the hazards that contamination may represent, it is essential to understand both risk assessment and risk management. Central to this understanding are tremendous uncertainties that distinguish groundwater pollution problems and the health risks they present.

On the whole three general sources of uncertainty in groundwater contamination should be considered. First, there is uncertainty in the theoretical and mathematical models describing the physical, chemical and biological processes of contaminant transport, human exposure and dose–response relationship. Second, there is uncertainty in the input data for the models. Finally, there is uncertainty in the policy analyses of risks and in the decisions made for controlling risks.

Because of these uncertainties, a number of simplifying assumptions is generally considered, which may lead to underestimates of risk. To this end, sensitivity analysis and decision analysis can be helpful in identifying which of the multiple uncertainties in groundwater contamination risk assessment have significant impact on management decisions. Moreover, unsaturated zone monitoring will be very important when trying to reduce uncertainties in exposure assessment from groundwater contamination. Measurement of water content, matrix potential and concentrations at varying depths in the unsaturated zone are needed. The necessity to quantify the uncertainty in predictions of the travel times of hazardous contaminants has focused attention on the need for stochastic models of the media properties. Observations of exposures of different types of porous media have shown that physical properties vary enormously even in individual geological formations.

This variability results in correspondingly large variations in flow parameters. Characterise the spatial variability through a stochastic model defined by a relatively small number of statistical parameters, could be a way to incorporate this natural heterogeneity into flow and transport models. When the contaminant of concern is an immiscible fluid with water, multiple phase flow must be considered. Additional complexities arise in multi-phase flow problems.

On the whole, dynamic and stochastic simulation models of water flow and solute transport in the saturated and unsaturated zones, which take proper consideration of time lags, buffering and inertia of the aquifers and handle non-point source pollution and non-stationary conditions, in combination with carefully selected field experiments, are crucial tools for proper assessment and management of groundwater contamination.

In this field more concern and studies are needed with reference to:

-multiphase flow and transport
-linkage of geochemical and physical transport models
-probabilistic methods for modelling groundwater systems.

Another theme strictly related to groundwater pollution and, particularly, to the chemical and biological processes and mass movement in the unsaturated zone, which the Group’s activity is nowadays focusing on, concerns the water and solute transport phenomena in the soil–plant–atmosphere system.

It is well know that the rate of water and salt uptake by the root system depends not only on the capacity of the soil to supply water and solute to the roots at a rate which ensures both plant transpiration and growth, but also on plant properties and atmospheric conditions.

Plant resistance to salinity, physiological plant adjustment to water stress, rooting depth and soil-water properties at different moisture contents determine the actual salt-water uptake by plants in response to the demand imposed by the atmosphere.

The presence of such complex interactions makes it difficult, therefore, to study particular aspects of the water and solute transport process. Moreover, interpretation of both laboratory and field experimental tests has often been impossible due to the difficulty in dealing with the phenomenon, and attempts to isolate system variables have often led to mistaken analyses. So a new global approach is needed, in order to achieve a better understanding of the behaviour and evolution of the soil-plant-atmosphere system.

Research needs to be carried out to investigate more deeply the relationship between plant growth and water and salt in the soil.

A more precise estimation of the crop water requirements must be attained in order to ensure improvement in yields, water saving and, consequently, a greater availability of water resources. On this ground crop-water models have shown to be essential tools for research.

In this way a better understanding of the effects of various irrigation strategies on plant growth and groundwater pollution and recharge will be achieved. On the whole, there is a large scope of research on the following topics:

-evapotranspiration and related calculation methods
-optimum fertilisation procedures
-scale dependence of soil physical properties and processes
-preferred pathway flow phenomena
-parameter identification and simulation models for transport and degradation of chemicals in soil
-flux measurement in the unsaturated zone
-soil-rhizosphere interaction.

The integrated systems approach for developing and testing groundwater simulation models suggests potential links to GIS (Geographic Information Systems) technology. In conceptual terms, GIS seem well suited to address data and modelling issues that are associated with a modelling environment that includes multi-scale processes, all within a complex and heterogeneous domain. GIS can help address data integration questions associated with multi-scale data from ground-based and/or remote sensing sources. GIS could potentially support exploratory analyses of complex spatial patterns and hydrodynamic processes. Finally, advanced coupled quality-quantity groundwater models require detailed spatial data, which provide an opportunity for innovative thematic mapping and error analyses with GIS. To this end, GIS can contribute to spatial data issues and help in understanding complex physical phenomena. Frequently there is uncertainty in how to define requirements for parameter and input identification for advanced groundwater models. Such uncertainty often stems from incomplete knowledge about fundamental processes, scaling from small to large area estimates, methods for integrating and aggregating data in space and time, and the interrelationship of data sets in space and time. GIS can help meet these requirements and provide the flexibility for the development, validation, testing and evaluation of such data sets that have distinct temporal components. Capabilities are needed to convert existing data sets into derivative data sets with provisions for flexible scaling, multiple parameterisations and classifications, grid cell resolutions, or spatial aggregations and integration.

Nowadays, GIS seem mainly used as pre-processors to prepare spatially distributed parameters and input data, and as post-processors to display and possibly analyse model results, while modelling approaches directly built into GIS appear to be rare. It is reasonable to hope that in the future, with more powerful and affordable computer technology, the integration of GIS and groundwater models can proceed more speedily along the two following major themes:

-database issues
-analysis and modelling issues.

To sum up, the Group’s policy on groundwater engineering focuses on the approach of sustainable development and integrated management of subsurface resources. The emphasis is on the analysis of groundwater systems, the modelling of flow and contaminant transport processes, and the design and maintenance of comprehensive monitoring networks, which represent basis tools for understanding and assessing aquifer stresses and disturbances and bring forth key-information for management strategies broadly defined.

With reference to the above-mentioned subjects the SIG on Soil and Water aims at providing an international forum for state-of-the-art presentations on relevant methodologies and techniques, and the identification of the needs for future development. The Group, by means of scientific and technical meetings, guidelines and handbooks, will also attempt to illustrate the applicability of various techniques through advanced case studies on calibration and reliability assessment.

Cooperation with other national or international organisations impinging upon similar themes are solicited and welcomed, with the aim of addressing problem identification, process description and modelling. The ultimate aim is to help young scientists and professional determine critical factors and methods in their evaluation of uncertainty throughout the modelling process.

In this endeavour, the Group is nowadays interacting with other International Institutions, with the aim of establishing a permanent structure able to address groundwater investigation and modelling issues. The Group hopes, in this way, to develop a regional framework in the Groundwater Engineering field, and to consolidate its relationship with the European scientific community.

Prof. Daniele De Wrachien
Chairman EurAgEng SIG on Soil and Water

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