Metsa kasvukäigu püsiproovitükkide rajamine veetaseme muutuse mõju jälgimiseks Aidu karjääris
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Kuupäev
2012
Kättesaadav alates
ainult raamatukogus, only in library
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
Aidu karjääri põlevkivi tagavara ammendumisel 2012. aastal kaevandus suletakse ja
sellega seoses katkeb ka vee väljapumpamine, mis seni on alandanud põhjavee taset.
Antud töö eesmärgiks oli rajada Aidu karjääri tasandatud puistangutel asuvatesse
puistutesse metsa kasvukäigu püsiproovitükid ning fikseerida sellega puistute seisukord
enne karjääri sulgemist ning sellega kaasnevat veerežiimi muutust. Antud töö käigus
rajati 60 proovitükki erivanuselistesse puistutesse, kus peapuuliikideks olid harilik
mänd ja kask. Lisaks võeti proovitükkidelt mullaproovid, milles määrati toiteelemendid
ja pH. Mulla parameetrite ja puistute takseerandmete vaheliste seoste leidmiseks
analüüsiti andmeid dispersioon- ja regressioonanalüüsiga.
Töö tulemusena selgus, et kaheksal proovitükil oli algselt kultiveeritud mänd
asendunud kasega. Kaasikute mullakihi keskmine tüsedus (38,6 cm) erines oluliselt
männikute mullakihi keskmisest tüsedusest (6,1 cm). Analüüside tulemustest ilmnes, et
lehtpuude osakaalu suurenedes kasvasid usaldusväärselt mullakihi keskmine tüsedus,
mulla lämmastiku- ja fosforisisaldus, orgaanilise süsiniku sisaldus ja kõdukihi tüsedus
ning vähenes usaldatavalt mulla pH tase. Puistu kõrguse kasvades suurenes
usaldusväärselt kõdukihi tüsedus, mullakihi tüsedus, fosfori- ja lämmastikusisaldus
ning orgaanilise süsiniku sisaldus, vähenes usaldusväärselt mulla pH tase. Puistu
vanuse suurenemisega kasvas usaldusväärselt mulla kõdukihi tüsedus, lämmastiku- ja
fosforisisaldus, ning vähenes usaldusväärselt mulla pH tase. Puude keskmise diameetri
suurenedes kasvasid usaldusväärselt kõdukihi tüsedus, mullakihi tüsedus, fosfori- ja
lämmastikusisaldus, orgaanilise süsiniku sisaldus ning vähenes usaldatavalt pH tase.
Antud analüüside tulemused näitavad kasvukoha paranemise trendi aja jooksul.
Aidu karjääris on sulgemisjärgselt plaanis stabiliseerida põhjaveetase 42 m kõrgusel
merepinnast. See põhjustab vähemalt kahe proovitüki jäämist vee alla ja nelja
proovitüki muutumist liigniiskeks, mistõttu võivad muutuda mulla omadused ja seeläbi
ka puude kasv. Oluline on läbi viia puistu- ja mullainventuur samadel proovitükkidel
peale veetaseme stabiliseerumist Aidu karjääris.
Due to the exhaustion of oil shale resources in Aidu quarry in 2012, the quarry will be closed, as a result of which the pumping of water for reducing groundwater level will be interrupted. The purpose of this thesis was to establish permanent forest yield sample plots in stands located in the levelled heaps of Aidu quarry and determine the condition of stands before the closing of the quarry and related changes in the water regime. In the course of research, 60 sample plots were established in stands of various ages where Scots pine and Silver birch were the main tree species. In addition, soil samples were collected in the plots, and nutrients and pH level determined. For finding correlations between soil parameters and stand survey data, the data was analysed using dispersion and regression analysis. Results revealed that in eight sample plots, Scots pine initially planted had been replaced with Silver birch. The average soil thickness (38.6 cm) in birch forests differed significantly from that of pine forests (6.1 cm). Analysis results showed that an increase in the proportion of deciduous trees corresponded to a significant growth in average soil thickness, soil organic carbon, nitrogen and phosphorus content, litter layer thickness, and to a significant decrease in soil pH level. In correlation with stand height growth, average soil thickness, litter layer thickness, soil phosphorus, organic carbon and nitrogen content increased significantly, whereas soil pH level decreased significantly. In correlation with stand age growth, soil nitrogen and phosphorus content as well as litter layer thickness increased significantly, whereas soil pH level decreased significantly. In correlation with average tree diameter growth, average soil thickness, litter layer thickness, soil phosphorus, organic carbon and nitrogen content increased significantly, whereas soil pH level decreased significantly. The results of the above analyses show a trend towards site improvement over time. After closing, groundwater level will be stabilised in Aidu quarry at 42 metres above sea level. This will leave at least two sample plots under water and four sample plots with excessively high moisture levels, thereby changing soil properties and tree growth. It is necessary to conduct stand and soil inventories in the same sample plots after water level has been stabilised in Aidu quarry.
Due to the exhaustion of oil shale resources in Aidu quarry in 2012, the quarry will be closed, as a result of which the pumping of water for reducing groundwater level will be interrupted. The purpose of this thesis was to establish permanent forest yield sample plots in stands located in the levelled heaps of Aidu quarry and determine the condition of stands before the closing of the quarry and related changes in the water regime. In the course of research, 60 sample plots were established in stands of various ages where Scots pine and Silver birch were the main tree species. In addition, soil samples were collected in the plots, and nutrients and pH level determined. For finding correlations between soil parameters and stand survey data, the data was analysed using dispersion and regression analysis. Results revealed that in eight sample plots, Scots pine initially planted had been replaced with Silver birch. The average soil thickness (38.6 cm) in birch forests differed significantly from that of pine forests (6.1 cm). Analysis results showed that an increase in the proportion of deciduous trees corresponded to a significant growth in average soil thickness, soil organic carbon, nitrogen and phosphorus content, litter layer thickness, and to a significant decrease in soil pH level. In correlation with stand height growth, average soil thickness, litter layer thickness, soil phosphorus, organic carbon and nitrogen content increased significantly, whereas soil pH level decreased significantly. In correlation with stand age growth, soil nitrogen and phosphorus content as well as litter layer thickness increased significantly, whereas soil pH level decreased significantly. In correlation with average tree diameter growth, average soil thickness, litter layer thickness, soil phosphorus, organic carbon and nitrogen content increased significantly, whereas soil pH level decreased significantly. The results of the above analyses show a trend towards site improvement over time. After closing, groundwater level will be stabilised in Aidu quarry at 42 metres above sea level. This will leave at least two sample plots under water and four sample plots with excessively high moisture levels, thereby changing soil properties and tree growth. It is necessary to conduct stand and soil inventories in the same sample plots after water level has been stabilised in Aidu quarry.
Kirjeldus
Märksõnad
taasmetsastamine, põlevkivikarjäärid, veerežiimi muutus, Aidu, bakalaureusetööd