Hüdromelioratsiooni mõju hariliku männi (Pinus sylvestris L.) radiaalsele juurdekasvule sõltuvalt kuivenduskraavi kaugusest
Laen...
Kuupäev
2014
Kättesaadav alates
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Metsahüdromelioratsiooni tulemusi on kirjeldatud mitmetes varem ilmunud
uurimustöödes, kuid enamik nendest põhineb siiski sellistel andmetel, mille ajaline
eraldusvõime ei ole kõrge. Töö eesmärgiks oli uurida kuivendusjärgseid muutusi
puude radiaalse juurdekasvu dünaamikas. Dendrokronoloogiliste meetoditega uuriti
puursüdamikest (võetud hariliku männi mudelpuudest, kraavist 150–300 meetri
kaugusel) mõõdetud aastarõngaste laiuste varieeruvust perioodil 1776–2013. Töö
tulemusena selgus, et Kanajalasoo kuivendustööd algasid vähemalt 10 aastat varem,
kui seni on kirjanduses nimetatud. Uuritud ala piires ei olnud puude radiaalse
juurdekasvu dünaamikas täheldatud otsest seost kaugusega kuivenduskraavist, mis
võib olla tingitud nii uuringuala paigutamisest ümbritsevas maastikus kui ka
suhteliselt tagasihoidlikest melioratsioonitööde tulemustest valitud kaugustes kraavist.
Üldistuste tegemiseks on vaja uuringut edaspidi laiendada ning kasutada kraaviäärsete
mudelpuude andmeid. Saadud andmestik sisaldab endas mitte ainult
kuivendustöödega põhjustatud muutusi, vaid ka informatsiooni möödunud kliima
kohta. See võib leida kasutust näiteks kasvutrendide rekonstrueerimisel ja
modelleerimisel või ka kuivenduse positiivse keskkonnamõju hindamisel.
Results of forest drainage activities are described in a number of earlier published studies, however most of them are based on data, which temporal resolution is not very high. The aim of the current study was to evaluate post-drainage changes in radial growth dynamics of the trees. Tree-ring width variations (measured from increment cores, that were taken from the sample Scots pine trees, distance from the drainage ditch of which varied within 150-300 meters) in the period 1776-2013 were analysed using dendrochronological methods. The study showed that drainage of Kanajalasoo bog had started at least 10 years earlier than was previously mentioned in the literature. Dependence of the dynamics of radial increment of trees on the distance from drainage ditch was not observed within the study area, this could be due to sample plots location in the surrounding landscape as well as relatively modest postdrainage growth release at selected distances from the ditch. The study needs to be expanded by using data of sample trees that are closer to the drainage ditch in order to suggest any generalizations. The resultant dataset contains not only drainage-induced variations, but also the information on the past climate. It can be used, for example, in growth-trends modeling and reconstruction or in assessments of positive environmental impact of the drainage activities.
Results of forest drainage activities are described in a number of earlier published studies, however most of them are based on data, which temporal resolution is not very high. The aim of the current study was to evaluate post-drainage changes in radial growth dynamics of the trees. Tree-ring width variations (measured from increment cores, that were taken from the sample Scots pine trees, distance from the drainage ditch of which varied within 150-300 meters) in the period 1776-2013 were analysed using dendrochronological methods. The study showed that drainage of Kanajalasoo bog had started at least 10 years earlier than was previously mentioned in the literature. Dependence of the dynamics of radial increment of trees on the distance from drainage ditch was not observed within the study area, this could be due to sample plots location in the surrounding landscape as well as relatively modest postdrainage growth release at selected distances from the ditch. The study needs to be expanded by using data of sample trees that are closer to the drainage ditch in order to suggest any generalizations. The resultant dataset contains not only drainage-induced variations, but also the information on the past climate. It can be used, for example, in growth-trends modeling and reconstruction or in assessments of positive environmental impact of the drainage activities.
Kirjeldus
Märksõnad
bakalaureusetööd