Soil Survey in Greece

EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6 Soil Survey in Greece N. Yassoglou Laboratory of Soils and Agricultural Chemistry, Agricultural Universi...
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EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6

Soil Survey in Greece N. Yassoglou Laboratory of Soils and Agricultural Chemistry, Agricultural University of Athens, Athens, GREECE

Introduction Soil survey in Greece was initiated in the 1930s. Over the ensuing years it has followed several stages of development. Programmes have been interrupted several times and restarted by different agencies, such that there has never been a continuous programme likely to result in the complete mapping of the country. Soil classification and mapping designation schemes have varied. Classification schemes used have included the Russian system (Glinka 1927), the 1938 USA system (Thorp and Baldwin, 1938), the French system (Aubert and Duchaufour, 1956), Soil Taxonomy (Soil Survey Staff, 1975) and the FAO system (FAO/UNESCO, 1990). Soil mapping is carried out by a number of organisations in Greece and at a number of different scales. Soil maps at reconnaissance scale have been produced for various parts of the country, mainly to provide a scientific basis for agricultural development at a regional scale. A series of maps at a detailed scale has been produced by the Soil Reclamation Service in Cupertino together with the Soil Laboratories of the Ministry of Agriculture. These maps were mainly of arable bottomlands and the units were adapted to provide information suitable for drainage and irrigation advice. The Forest Service has been undertaking land mapping of the hilly and mountainous areas of the country at a 1:50,000 scale. Such maps are used to plan the sustainable development of non-agricultural lands. Summaries of the mapping progress for the period to 1989 are to be found in Aggelides and Theocharopoulos (1991) and for the period to 1994 in Yassoglou (1996). Progress in the last ten years (to 1998) is described below.

Present Status of Soil Mapping Small scale mapping A soil association map at 1:500,000 scale has been prepared for the whole country. Its mapping units have been designated on the basis of geology, geomorphology, physiography, vegetation zone and land cover. An algorithm was developed for overlaying the parameters (Yassoglou and Kollias, 1989). The so-constructed map was checked and corrected in the field. A 1:1,000,000 map, prepared by uniting similar units from the 1:500,000 map, has been incorporated in the European Soil Bureau Database.

Reconnaissance and semidetailed mapping The areas mapped at semi-detailed and reconnaissance scales (1:50,000 to 1:300,000) amount to roughly 4 million hectares or about 31% of the total country. Much work is required to bring them to currently acceptable standards because of the different methodologies and classification systems used over the years. The number of profiles analysed is not exactly known but is estimated to amount to a few hundred. Figure 1 shows the areas within which this type of soil mapping has been conducted.

Land mapping The Greek Forest Service has been conducting land mapping based on the site parameters: geology, physiography, vegetation, degree of human interference, soil depth, soil erosion, aspect and slope. The mapping units are defined parametrically and drawn on to 1:50,000 maps using parametric overlaying (Nakos, 1983). Each map is checked and corrected in the field.

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Figure 1: Areas within which reconnaissance soil surveys have been conducted.

In the course of the mapping programme, more than 2000 profiles have been described, sampled, analysed and classified according to the Soil Taxonomy and FAO systems. These data are now stored in computerised databases.

mountainous areas of the country. The land maps are valuable for developing sustainable land use schemes in the uplands.

The total area mapped is estimated to be more than 10 million hectares, almost 100 percent of the hilly and mountainous lands and 75% of the total area of the country. Land mapping is not strictly soil mapping but it is a useful reference for the construction of soil maps in the hilly and

Detailed soil mapping has so far been confined to low lying agricultural lands and the surrounding hills. The field sheets on which the soil boundaries are originally drawn are at a scale ranging from 1:5,000 to 1:15,000. The published map scales range from 1:5,000 to 1:20,000.

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Detailed Soil Mapping

Soil Survey in Greece. Yassoglou

EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6 The soils are grouped into taxonomic units according to a combined taxonomic and parametric system. They are first classified to the level of Great Soil Group according to Soil Taxonomy (Soil Survey Staff, 1975 and subsequent modifications) and then further subdivided according to a number of soil parameters. The parameters used are those that play key roles in the performance and management of the soil, such as landscape characteristics, drainage, texture of each soil horizon, slope, evidence of erosion, abundance of carbonates, and specific limitations which, if present, strongly affect soil performance. The symbol of the mapping unit includes coded taxonomic, soil and landscape notations. The map is drawn in the field by the soil surveyor on an aerial photograph or on a large-scale topographic map. Profiles are sampled and analysed and stored in databases. The area so far mapped in detail covers approximately 600,000 hectares, corresponding to about 30 per cent of the high quality agricultural land and 4.6 per cent of the whole country. The areas mapped according to standard soil survey procedures are located within the boundaries sketched in Figure 2. Several non-standardised soil surveys, with scope limited to the needs of irrigation projects, cover about 2 million hectares of the agricultural lands. The mapping units of these surveys do not meet the standard requirements, the data collected are incomplete and they have not been recorded in electronic databases. However, they could provide some valuable information. This type of mapping has now been replaced by standard soil surveys. The rate of detailed mapping has slowed in recent years because of a lack of an ongoing strategy for national mapping. At present soils are mapped on request by local authorities to meet the needs for information to plan irrigation, environmental management, agricultural management and land planning.

Databases Soil databases exist in a number of institutions, where topological and semantic data are stored (Theocharopoulos et al., 1992; Kollias and Malliris, 1990). Soil profile data included are area, horizon designation and depth, textural class (sand, silt, clay), cation exchange capacity, exchangeable cations, organic matter, pH, carbonates, total nitrogen, electrical conductivity, bulk density, soluble salts, sodium saturation. Water infiltration, permeability and bulk density are occasionally recorded.

These databases institutions: 1.

2. 3. 4. 5.

reside

at

the

following

Soil Mapping and Classification Institute in Larissa. The GIS systems in use are ARC/INFO and LASER-SCAN Agricultural University of Athens, where data are stored in ARC/INFO. Soils Institute of Athens using the ORACLE system. Agronomy Department of the University of Thessaloniki, using ARC/INFO. Institute of Mediterranean Forest Ecosystems and Wood Technology in Athens, where only semantic data are stored in the database.

The weak points of the Greek soil databases are that they are not interlinked and data are not freely available to the public. It has been proposed that all available data are gathered and stored by the Soil Mapping Institute in Larissa which would become the reference point for all national soil information.

Soil Monitoring At present little systematic soil monitoring exists in Greece. Some monitoring is being conducted by the Institute of Mediterranean Forest Ecosystems in Athens as part of a research project funded by the European Union.

Use of the Soil Databases The usefulness of soil data has not been recognised in the past to the degree that it deserved. This has been due mainly to lack of knowledge on the part of users on how to apply soil information and inadequate teaching of soils in curricula of agronomists and foresters. Another reason has been the fact that soil survey reports were in the hands of a small number of governmental services and prospective customers were unaware of their existence and usefulness. However, there are recent signs of a much better appreciation of soil data by local authorities and communities. The main uses made of the soil databases in Greece are described in the sections below.

Land Reclamation The primary use made of the databases is in relation to land reclamation and improvement. Soil topological and semantic data have significantly contributed toward the development of intensive irrigated agriculture in more than 60% of the valuable Greek bottomlands

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EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6 The databases have been used in the setting of priorities and the designing and operating of irrigation works. Mapping units have been classified into irrigability classes according to the system developed by the US Bureau of Reclamation (1953) based on soil, topographic and drainage deficiency levels. Irrigation networks were constructed in soils classified as highly irrigable. Soil data have been used in determining the water needs of major irrigated agricultural crops.

Saline and sodic soils have been reclaimed on the basis of soil chemical, physical and morphological data provided by soil studies conducted on behalf of the Soil Reclamation Service.

Crop Selection An important part of the detailed soil survey reports has been land evaluation in terms of the suitability of soil and climate for the major crops grown in the country.

Soil data such as morphology, texture, surface and subsurface water permeability have been used in designing and constructing drainage systems in the flood basins of the country.

Figure 2: Areas within which detailed soil surveys have been conducted.

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EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6 Soil mapping units have been classified into relative suitability classes on the basis of related morphological, physical, chemical and climatic parameters. The procedures followed are mainly qualitative, based on the system developed by Sys (1985). Models of quantitative evaluation have been applied in only a few cases (Danalatos, 1993). National and local strategies of crop selection can be developed and implemented on the basis of soil-climate suitability along with consideration of present and the projected economical, social and political conditions prevailing in the local, national and international environments.

Land Quality, Degradation and Environmental Assessments Soil data have been used in the assessment of land quality and erosion risks (CORINE, 1992). Soil parameters used, along with vegetation index and climate quality for the determination of land quality classes, were soil texture, depth, drainage and slope angle. Erosion risk was assessed from soil texture, soil depth, stoniness, slope angle, land cover and climatic erosivity.

Lands were classified into one of the following classes of potential and actual land quality and erosion risk: none, low, medium or high classes. Respective maps and tabular data have been stored in the CORINE database. Detailed soil survey data have been used in determining “Environmentally Sensitive Areas” (ESAs). Emphasis has been given to the assessment and mapping of soil erosion and desertification risks. Such pilot assessments have been conducted in the Greek Island of Lesvos as shown in Figure 3 (Kosmas, et al., in press), in Italy and in Portugal. Soil indicators used were parent material, texture, depth, drainage, rock fragments and slope. The implementation of the National Action Plan to Combat Desertification, which has been recently prepared (Yassoglou, 1999), is expected to make extensive use of the existing soil databases. The main applications are likely to be in the selection and delineation of priority areas, in the decisions to be made on the kind and extent of interventions and in the estimation of cost/benefit ratios. Soil surveys have provided basic data for regional planning in several areas of Greece.

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The Institute of Soil Mapping and Classification in Larissa has prepared a number of reports on the environmental impacts of various development projects. The expected changes in the performance and the effects of the construction of major public works on the soil environment have been evaluated on the basis of soil maps and on the related soil data provided by the soil survey reports.

Application of Fertilizers The 1:1,000,000 soil database has been used for assessing the suitability of agricultural soils for fertilisation with urea (Yassoglou, 1990). The mapping units were characterised as low, medium and highly suitable and a map has been prepared. These assessments were used to estimate the projected quantities of urea fertiliser that Greece could consume annually. Data contained in soil survey maps and reports have been used in the application of site specific fertilisation. The private company «VELESTINO» has introduced this programme in combination with the production of blended fertilizers.

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The amounts of fertilizers required are estimated and the mode of application is prescribed for each farm and each major crop. The basis of this work is the morphological and physical properties of corresponding soil typological units, the results of soil tests and the requirements of the specific crops. About 3,000 sites have been tested so far and appropriate fertilisation practices have been prescribed in each one of them. This programme also contributes toward better environmental practices, by reducing the chances of overfertilisation and contamination of ground water with nitrates.

Forest Management Land mapping has provided basic data for better forest management. Site characteristics, such as parent material, physiography aspect, soil typological unit, soil depth, slope and surface stoniness, employed in the description and designation of land units, are used in classifying forest sites into suitability classes for various species. Such information has also been used in the selection of sites for intensive management and reforestation (Nakos, 1984)

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EUROPEAN SOIL BUREAU  RESEARCH REPORT NO. 6 2.

Other Uses The Government has been engaged in farm consolidation due to the fact that a serious inefficiency of Greek agriculture is the high degree of farm fragmentation. Soil surveys have been used on some occasions in reallocations of land. This application must be expanded to secure more efficient farming and to prevent injustices and complaints on the part of the farmers.

3.

4. Soil survey data have also been used in archaeological studies (Yassoglou and Nobeli, 1972). Soil maps and profile data have contributed in identifying locations of buried settlements and structures, old land use patterns and past population densities.

5.

6.

Outlook

Soil survey reports should be made more userfriendly, contain instructions for the users and become more widely available to the public. Mapping units should have a more pronounced bias towards practical applications. They should be easily recognised and understood by a wide spectrum of users. The 1:250,000 Soil Manual prepared by the European Soil Bureau (ESB, 1998) is an example, which could be further improved and expanded. Soil mapping groups should establish close ties with local, national and international bodies, and seek new sources of funding for soil mapping projects. Soil databases should be improved and extended, and links secured at national and international levels. There should be experiments with new technologies for collecting, classifying, and interpreting soil information.

There is increasing interest in soil information in Greece, which needs to be taken seriously and satisfied. The following recommendations would go some way in improving the quality and availability of soil information: 1.

The importance of soils should be taught at all levels of education

References Aggelides S. and Theocharopoulos S.P. (1991). Soil mapping in Greece. In: Soil Survey – A Basis for European Soil Protection . J.M. Hodgson (ed). Soil and Groundwater Research Report I, EUR 13340 EN, 61-63. Office for Official Publications of the European Communities, Luxembourg. Aubert, G, et Duchaufour P. (1956). Projet de classification des sols VIe congrès international de la science du sol, Paris, Vol. E 597-604. CORINE (1992). Soil erosion risk and important land resources in the southern regions of the European Communities. EUR 13233 EN, Luxembourg. 96 pp. Danalatos, N.G. (1993). Quantified analysis of selected land use systems in the Larissa Region, Greece. Doctorate Thesis. Agricultural University, Wageningen, 370 pp. ESB (1998). Georeferenced Soil Database for Europe, Manual of Procedures Ver. 1. European Soil Bureau, Scientific Committee. EUR 18092 EN, 184pp. Office for Official Publications of the European Communities, Luxembourg.

FAO/UNESCO. (1990). Soil map of the World. Revised legend. World Resources Report 60. FAO United Nations, Rome, 119 pp. Glinka, K.D. (1927). The Great Soil Groups of the World and their development. Ann Arbor Michigan, 235 pp. Kollias, V.J. and Malliris, A.G. (1990). A prototype multidatabase system for soil databases. Computers and Geosciences, 16, 331-339. Kosmas, C., Ferrara, A., Briassouli, H. and Imeson, A. (In press). A methodology for mapping environmentally sensitive areas. In: C.Kosmas, M. Kirkby and N. Geeson. (Eds.) Manual on indicators of desertification and mapping environmentally sensitive areas to desertification. European Commission. Nakos, G. (1983). Land resources survey of Greece. Journal of Environmental Management, 17, 153-169. Nakos, G. (1984). Forestry development and reforestation. Greece. Site and soil survey: Anthrakia pilot plantation area. FO: DP/GRE/78/003 working document no 20, UNDP-FAO Athens.

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Soil Survey Staff. (1975). Soil Taxonomy. Agriculture Handbook no 436. Soil Conservation Service, USDA, 754 pp.Sys, C. 1985. Land Evaluation. Intentional Training Center for Graduate Soil Scientists. State University of Gent. Theocharopulas, S.P., Papadopulos, N.Th. and Papademos, G. (1992). Management soil database (SOILDB). Agr. Reseearch 16, 1-12 {Grk]. Thorp, J. and Baldwin, M. (1938). New nomenculture of the higher categories of soil classification as used in the Department of Agriculture. Proc.Soil Sci. Soc. Am. 3, 160268. US Bureau of Reclamation. (1953). Reclamation Manual, Vol. V: Irrigated land use, Part 2. Land classification. USBR, Denver, Colorodo, USA. Yassoglou, N.J. and Nobelli, C. (1972). Soil studies. In: W.A. McDonald and G.R.Rapp Jr. (Eds.) The Minnesota Messenia expedition/ Reconstructing a Bronze Age regional environment. The University of Minnesota Press, pp171-176. Yassoglou, N.J. and Kollias, V.J. (1989). Computer assisted soil mapping for the evaluation of soil erosion risk and land quality in Greece. In: H.A.J. Van Lanen and A.K.Bregt (Eds.). Agriculture. Application of computerized EC soil map and climate data. Comm. Eur. Comm., EUR 12039 EN, p. 237246. Yassoglou, N.J. (1990). A study of the conditions and prospectives for the use of urea as a nitrogen fertilizer in Greek soils. Report submitted to the Nitrogen fertilizers Company of Greece {Grk.} 23pp. Yassoglou, N. (1996). Greece. Soil mapping and soil databases. In: Soil Databases to Support Sustainable Development. C. Le Bas and M. Jamagne (eds.) European Soil Bureau Research Report No. 2, p.57-60. EUR 16371 EN. Office for Official Publications of the European Communities, Luxembourg. Yassoglou, N.J. (ed). (1999). The Greek action plan for combating desertification. A document submitted to the Greek Government. {Grk}

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