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Land Information Systems in Greece past, present and future

By Calvin Mcdonald,2014-06-12 04:32
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    EUROPEAN SOIL BUREAU RESEARCH REPORT NO. 4

    Land Information Systems in Greece:

    past, present and future

    Among soil scientists, the concept our land resources, two Introduction of "land" is not to be confused nationwide surveys of land are

    with "soil"; because land is wider currently being undertaken in About two-thirds of Greece is than soil and soil is a part of the Greece. The first survey is mountainous country; only about land. The concept of land designed to further agricultural 4 million out of a total of 13.2 involves its physiography, planning by identifying the million hectares of its land is hydrology, climate, soil, etc. To detailed soil units of each area arable. In mountainous areas, describe land, one refers to its and provide some additional animal husbandry and forestry are land characteristics (single or laboratory results related to these the major sources of income and compound). Examples of land map units. The second survey large tracts are rocky outcrops characteristics are: slope, total determines the suitability of completely devoid of vegetation rainfall, soil depth, soil moisture terrain for forestry. While the or covered with brush and shrubs. holding capacity etc. Complex measures and classification Greece’s 13.2 million ha are clusters of land characteristics are scheme used to date by the two classified into four major land qualities. surveys are different, the end categories as follows: 30% arable, product is a similar mosaic of 44% pastures, 19% forest and 7% For the study of a Land Use polygons, each containing a other uses. System, we must describe the classification symbol. Land Utilization Type (LUT) with its key attributes that reflect The main mission of the forestry the biological, socio-economic, survey is an inventory of those technical and other aspects of the areas which are not suited to production environment that are agriculture, but would support relevant to the land’s production timber or range production. The capacity. We are aware of the polygon mosaic is produced by a single land use systems that is combination of aerial and ground LU-LUT in combination; multiple surveys and by reference to systems that have more than one 1:50,000 contour maps. Currently crop on the same field at the same only one thematic map and one T. Lelentjis time, and compound systems that interpretive map are produced.

    are treated as concatenations of The result is a complete polygon J. Alatas single and/or multiple systems. mosaic with each area labelled as L. Toulios to its suitability for timber

    Also, it is known that a farming growth. The label is well suited to S. Floras system (FS) is made up from computerization, having a G. Kapetanak different land use systems (LUS), standard format with clearly practiced in the context of one defined and consistent meanings farming enterprise. To advance of each field in the label. The the above, the presence of a soil boundaries at the polygons in the National Agricultural information system is a mosaic are produced from

    Research Foundation prerequisite for land system topographic features and follow

    analysis. We are dealing here the natural curves of these Institute of Soil

    with the Soil Information System. features. Classification and Mapping Theofrasfou 1, Seeking improved environmental GR-41335 Larissa, GREECE quality and the conservation of

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    EUROPEAN SOIL BUREAU RESEARCH REPORT NO. 4

    In the case of the agricultural Survey legend The soil survey method maps, the labels imply different symbol systems in Greece interpretations of the symbols.

    A system of classification Also, on the agricultural maps, Field work symbols was developed by the boundaries are produced by

    Yassoglou and Henrard. This manual interpolation of curves Field teams of experienced system was ameliorated and between the sample points.Once surveyors examine a dense completed by Professor the two surveys have reached the network of soil profiles and draw Yassoglou in order to cover the most detailed category, they have the boundaries of each mapping soil conditions met in Greece far more in common, unit on either aerial photographs (Yassoglou et al, 1971). This computationally. Each detailed or, more commonly, on local system is based on the texture and map consists of a polygon mosaic maps at a scale of 1:5,000, drainage classes of the whole with areas labelled with a 1:10,000 or 1:20,000. The profile, the degree and trend of particular classification scheme. morphological characteristics of soil genesis, the topography and each profile are examined for erosion of the soil surface, the The survey for agricultural land classification purposes according presence of organic matter layers makes more detailed soil surveys to a system described below. The and gravels throughout the (1:5,000-1:20,000) and uses the Soil soils are further examined by profile, the presence of carbonate Taxonomy system. The second study borings to 1.50 m depth, made salts, the presence of a calcic or a (on the suitability of land for forestry) with a hard soil auger. The petrocalcic horizon, of soluble works on semi-detailed soil surveys distance between the borings salts (salinity-alkalinity) and the in mountainous forest land and uses ranges from 50 to 200 m, depth of salinity. All these photo-interpretation in combination depending on the uniformity of attributes are indicated with with the FAO Unesco soil the soils. For most soil types, letters or numbers in the mapping classification (maps at the scale of water infiltration rates are unit symbol (Figure 1.). The set 1:50,000). measured using the method of of symbols corresponds to the soil two concentric cylinders or a Phase. If the symbols of slope, single cylinder with a shallow erosion and textural class 0-25cm ditch around it. are dropped, then the combination of symbols corresponds to the soil series.

    Figure 1. Mapping unit symbol

     textural class order

     75-150 cm suborder

     textural class textural class great group

     25-75 cm 0-25 cm subgroup

     4 3 5

     Drainage class C ---------------------------------------- I o x v*

     slope A 0 1 k f s b

     erosion depth of alkalinity

     CaCO3

     calcic hor. presence

     alkalinity salinity * Ioxv : Inceptisol-ochrept-xerochrept-vertic

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    EUROPEAN SOIL BUREAU RESEARCH REPORT NO. 4

After finishing the field work A database includes levels of The ORACLE RDBMS observations and measurements, factors such as topographic

    and with all additional laboratory conditions, soil types, urban The ORACLE RDBMS is a high-results, the standardization of the structures and so on. These levels performance, fault-tolerant attributes is a desk exercise. are derived either from direct database management system, observation or from sources such especially designed for outline The field work map units are as published maps or aerial transaction processing and large matched with the final chemical photographs, and they are database applications. At the analytical data, making the registered with respect to a heart of the ORACLE RDBMS is proportional corrections, to common cartographic base. the SQL data language. SQL was construct the source map. Existing levels can thus be developed and defined by IBM selectively retrieved and Research and has been refined by The traditional method is based graphically transformed to the American National Standards on manual production of thematic generate new levels of site Institute (ANSI) as the standard maps. The thematic maps are : characteristics. The process is language for relational database soil map, soil series map, known as overlay mapping. management systems. SQL offers irrigability map, infiltration map, a complete set of data definition slope maps, calcium carbonate Geographic data processing is a and manipulation functions. map, etc. field that has grown from roots in geography and computing, and With SQL we can : from application areas ranging from the natural and social The transition from create tables in the database sciences to urban planning and store information in tables tradition to computer environmental management. It is select exactly the information we a field that has grown steadily need from our database. since the 1960s and continues to The transition from traditional make changes to our data and the grow in terms of the number of databases into GIS systems is a structure of underlying tables practitioners involved, the range major change. The introduction of combine and calculate data to of applications addressed and the RDBMSs in connection with the generate the information we sophistication of tasks performed. GIS have facilitated the whole need. procedure of delineation and evaluation of graphic and