Žemėnaudos struktūros kaita ir jos įtaka agrarinių kraštovaizdžių geodinaminiam stabilumui (Skiemonių seniūnijos pavyzdžiu)
LTReikšminiai žodžiai: Agrarinių kraštovaizdžių geodinaminis stabilumas; Geodinaminis stabilumas; Kraštovaizdis; Paviršiaus geodinaminio jautrumo vertinimas; Ūkininkavimas; Žemėnauda; Žemėnaudos struktūra; Žemėnaudos struktūros kaita; Change in land use structure; Farming; Geodynamic stability; Geodynamic stability of agro landscapes; Land use; Land use structure; Landscape; Surface geodynamic sensitivity evaluation.
ENLand use in a rugged terrain entails permanent surface erosion. The traditional farming in uplands where surface erosion processes are especially intensive is loss-making. Optimisation of traditional farming and use of ecological methods create premises for non-traditional trades. This requires rather great investments. Yet only the farms included in the governmental list can expect assistance of the state. As the agrarian reform is unfinished, not all farms are included in this list causing their owners various legal problems. The investigations embraced two topics: changes of land use structure and surface geodynamic sensibility. Complex evaluation allows distinguishing different land sensibility areas: accumulation and erosion zones in landed properties. The Skiemonys local district is composed of three different cadastre localities: Katlėriai, Mačionys and Skiemonys. The landed property in the Skiemonys local district covers 61.4% of the territory. The largest areas are covered by arable land (27.6%), pastures (18.0%) and meadows (15.8%) (Fig. 1). In 1990–2000, the area of arable land decreased by more than 3%, the areas of pastures increased by more than 2.5% and the area of meadows remained on the former level (Fig. 2). The process of landed property decrease in the Skiemonys local administrative district bears the same character as in the rest of the Lithuania territory. Urban territories cover 2.6% of the Skiemonys local district area (Table). Some new little settlements (rest-houses) were built in picturesque lakeside landscapes. The forest area has decreased by more than 2% (Fig. 3). Forest owners use timber as fuel but the trend of forest area decrease is not very pronounced. The different land use and landed property affect the geodynamic sensibility of the surface. Very sensible landscapes prevail in 12% of the territories of Skiemonys local district.The intensity of surface degradation in them is more than 3 mm/year. The sensible areas cover 8% of Katlėriai cadastre locality, 14% of Mačionys cadastre locality and 13% of Skiemonys cadastre locality. In some places where slope angle is more than 7ŗ and slope length is 100 m and more, farmers grow cereals and cultivated crops. The rates of erosion intensively increase to 14 mm/year. Cones sized 5x10 m develop at the slope bottom. All these areas will be transformed into pastures or forested. On the other hand, the areas of accumulation of material cover about 8% of the territory (Figs 4–6). They are mostly bogs and wetlands. The processes of accumulation also take place in the lakesides. Accumulation areas in the Katlėriai cadastre locality cover 3%, in Mačionys 12% and in Skiemonys 10% of the territory. Three groups of factors limit the transformation of landed property in geodynamic sensibility areas: fertility of landed property, the status and income of landowner. Traditional farming methods can be applied only in fertile landed property. In geodynamic sensibility areas, the landed property should be transformed. Yet, farmers are usually short of income to do this. Under these circumstances the transformation of landed property takes a natural course (Fig. 8). [From the publication]
