A study of changes in arable land in four rural municipalities of Tartu county

Maakasutuse muutused mõjutavad kliimat, pinnase ja veeressursside kvaliteeti, bioloogilist mitmekesisust ning inimeste toiduturvalisust. Seetõttu on oluline muutuste ja neid põhjustavate tegurite mõistmine. Magistritöö eesmärk on välja selgitada haritava maaga toimunud muutuste iseloom. Selle saavutamiseks vaadeldi Tartu maakonna neljas vallas toimunud haritava maa muutusi, mis olid autori poolt varasemalt digitaliseeritud. Kokku analüüsiti 725 muutust, millest 393 olid haritava maa muutused rohumaaks ning 332 haritava maa muutused metsamaaks (k.a võsastumine). Muutuste iseloomustamiseks valiti tegurid, millede sidumine kindla maatükiga toimus ESRI ArcGis tarkvaraga. Töö tulemustena leiti, et 46,5 protsenti juhtudest oli muu otstarbega maaks muutunud terve katastriüksuse ulatuses olnud haritav maa. Asula läheduses paiknes 7,3 protsenti uuritud tükkidest. Eelnevalt oli suure põllumassiivi osa 89 protsenti muutustest ehk 11 protsenti olid eraldi asunud tükid. Muutuste boniteet oli võrreldavatest aladest madalam 50,2 protsendil juhtudest. Kokku leiti 508 muutust, millel esines vähemalt üks haritava maa muutumisele võimalikku mõju omav tegur. Muutusi, kus selliseid tegureid ei esinenud, leiti 217 tükki. Meile teadaolevalt ei ole varasemalt Eestis sellist analüüsi läbi viidud. Üheks põhjuseks võib olla vajalikus formaadis algandmete puudumine. Töö edasisel uurimisel on võimalik valida juurde tegureid, millega muutusi iseloomustada. Samuti saab haritava maa muutuste põhjuseid uurida piirkondlikul skaalal, kus arvestatakse regiooni eripärasid (näiteks haritava maa müügi ja rendi hind, talunike sissetulek jne). Lisaks oleks taasiseseisvumisjärgse Eesti maakasutuse muutuste uurimisel abiks, kui saaks kasutada vektorvormingus digitaliseeritud 1978-1989 katastrikaarti.Land-use changes affect the climate, the quality of soil and water resources, biodiversity, and human food security. Therefore, it is important to understand the changes and the factors inducing them. The master's thesis aims to ascertain the nature of changes taken place with arable land. To achieve this, we examined the changes in arable land in four rural municipalities in Tartu County, which had been previously digitalized by the author. A total of 725 changes were analysed, 393 of which were the turning of arable land into grasslands and 332 were the turning of arable land into woodlands (including brushwood). To characterize the changes, the factors were selected, the binding of which with specific pieces of land took place by means of ESRI ArcGis software. As a result of the research, it was found that in 46.5 per cent of the cases all the arable land in a cadastral unit, had turned into land with some other purpose. 7.3 per cent of the studied pieces were located near populated places. 89 per cent of the changes had been previously been a part of large consolidated fields, i.e. 11 per cent had been pieces located separately. In 50.2 per cent of the cases, the site class of the changes was lower than that of comparable areas. A total of 508 changes were found with at least one of the factors possibly affecting the change in arable land. The total of changes, where such factors did not occur was 217. As far as we know, no such analysis has been previously carried out in Estonia. One reason may be the lack of original data in the required format. Upon further study of the research, it may be possible to choose additional factors to characterize the changes. The reasons for the change of arable land can also be examined at the regional scale, taking into account the specificities of the region (for example, the commercial value and rent price of arable land, the farmers' income, etc.). In addition, it would be helpful in the investigation of land-use changes in Estonia after the restoration of independence, if the 1978˗1989 cadastre map digitized in a vector format could be used