Changes in the condition of forest ecosystems exposed by technogenic emissions from nitrogen fertilizer plant under reduced pollution

Disertacijoje nagrinėjama technogeninės taršos pažeistų skirtingų miško ekosistemos komponentų (medyno, dirvožemio, krūmokšnių, žolinių augalų ir samanų danga) pokyčiai sumažėjus gamyklos AB „Achema“ taršai. Naudojant 26 metų (1981–2007) ir dabartinių metų (2011–2012) tyrimų duomenis yra atlikta analizė apie skirtingus miško ekosistemos komponentų pokyčius ir įvertinta miško ekosistemų atsikūrimo galimybės. Remiantis tyrimų rezultatais nustatyta, kad praėjus 10–20 metų laikotarpiui nuo gamyklos teršimo pradžios (1979 m.) gali atskurti pažeistos miško ekosistemos. Pirmiausia atsikuria pažeisti medynai, po to – dirvožemio cheminės ir biologinės savybės, vėliausiai – krūmokšnių, žolinių augalų bei samanų danga ir dabartinė ekosistemų būklė yra artima neužterštiems žaliašiliams. Tačiau arčiausiai gamyklos krūmokšnių, žolinių augalų ir samanų dangoje vis dar randami nitrofiliniai augalai, kurie nebūdingi neužterštiems žaliašiliams. Tai rodo, kad dėl medyno struktūros negrįžtamumo prie AB „Achema“ krūmokšnių, žolinių augalų ir samanų danga išlieka pakitusi.Doctoral dissertation presents the restoration of various components of forest ecosystem (stand, soil, the cover of brush, herbaceous vegetation and mosses) after the reduction of air pollution from the plant of fertilizers Achema. Using study data of 26 years (1981–2007) and of the current year (2011-2012), an analysis of the changes of different components of forest ecosystems has been carried out and recovery possibilities of forest ecosystems were evaluated. Based on the survey results it was found that after 10–20 years since the beginning of pollution from the factory (1979) damaged forest ecosystems are able to recover. First of all recover damaged stands, then – chemical and biological soil properties, at the latest – the cover of shrubs, herbaceous plants and mosses, and the current state of forest ecosystems is similar to control pine stands. However, ground vegetation in the nearest to the factory sites still contains nitrophilous plants which are not typical for uncontaminated pine forests. This shows that due to the irreversibility of the structure of stands near Achema, the cover of shrubs, herbaceous plants and mosses remains altered.Žemės ūkio akademijaVytauto Didžiojo universiteta

Impact of thinning on grass-plot vegetation in the pine forest

Magistro darbe tiriama ugdymo kirtimų įtaka pušynų žemutinių ardų augmenijos sudėčiai ir padengimui. Darbo objektas – Alytaus miškų urėdijos Sudvajų girininkija. Darbo tikslas – nustatyti 2003-2007 metų ugdymo kirtimų įtaką medyno žemutiniams ardams (trakui, pomiškiui, žolinei augmenijai, samanų dangai) Alytaus miškų urėdijos Sudvajų girininkijos miškuose, kuriuose yra atlikti ugdymo kirtimai. Darbo metodai – duomenys yra rinkti 2008 metais rugpjūčio-rugsėjo mėnėsiais. Tyrimai atlikti 5 sklypuose, kuriuose yra atlikti ugdymo kirtimai 2003-2007 metais. Panaudoti 25 ugdytų ir 5 neugdytų (kontroliniai) tyrimo barelių duomenys. Kiekviename barelyje aprašyti ir įvertinti miško fitocenozės komponentai: pomiškis, trakas, žolinė ir samanų danga. Bareliuose buvo registruojamos visos trako, žolių ir samanų rūšys, nurodant projekcinį padengimą procentais. O pomiškio medelių rūšys buvo registruojamos, nurodant jų skaičių vienetais. Darbo rezultatai. Ugdytuose sklypuose matomas ryškus augmenijos pagausėjimas. Padidėjus šviesos kiekiui po medynų lajomis daugėja ne tik rūšių, bet ir didėja jų padengtumas, taip pat vyraujančią padėtį paprastai užima miškui būdingos rūšys. Ugdymo kirtimai paskatino pomiškio ir trako atsiradimą. Ugdymo kirtimai turėjo įtakos žolinės augmenijos ir samanų rūšių skaičiui ir padengimui. Didžiausias augmenijos pagausėjimas stebimas trečiais-penktais metais po ugdymo kirtimų.In his master paper is evaluated the lower vegetation of impact of thinning on the undergrowth vegetation composition and cover. Object – is Sudvajai forest district in Alytus State Forest Enterprise. Objective – 2003-2007 to determine the impact of thinning lower vegetation (undergrowth, underwood, grassy vegetation, moss surface) Alytus forest enterprises Sudvajai forestry forests, which are carried out thinning. Methods – Investigations were carried out 5 parcels, wich are carried out thinning felling. Each site was chosen 10x10 sized barrels. Each was barely after 5 in the accouting area, wich was established moss, udergrowth and underwood species composition. Results. Thinning felling not represent the omptimum condition for the best trees to grow, but a good living conditions of the soil surfase to grow. Analysis of the data, increased number of species, since the thinning increase in amount of light crossing the living conditions of the soil surface to recover. For the reason new species have developed and it’s richness has increased. Therefore common forest species dominated even after the thinning.Žemės ūkio akademijaVytauto Didžiojo universiteta

Technogeninės taršos paveiktų/pažeistų miško ekosistemų būklės pokyčiai, sumažėjus taršai

Vytauto Didžiojo universitetasŽemės ūkio akademij

Changes of forest ecosystems affected by technogenic pollutants under reduced pollution

Vytauto Didžiojo universitetasŽemės ūkio akademij

The impact of thinning on ground vegetation in the pine forest

The aim of the study was to assess vegetation and undergrowth development after thinning in pine forest. 25 plots were selected in thinned and pine control stands of different years (from one to 5 years) after thinning. The size of the plots was 10x10 m. The data were collected in July of 2008 in Sudvajai forests district of Alytus forest enterprise. We recorded amount of saplings and projection cover in percent of undergrowth, herbs and mosses layers. It was determined that amount of saplings of pine and spruce increased after thinning. Projection cover of undergrowth, herb and moss layers increased after thinning. The highest projection cover was of Frangula alnus. The highest projection cover was 3-5 years after thinning. Overall species number increased after thinning. New non forest species appeared in the stands after thinning, therefore common forest species dominated even after the thinningVytauto Didžiojo universitetasŽemės ūkio akademij

Assessment of the health status of the Scots pine (Pinus sylvestris L.) forests near a highway

Aplinkotyros katedraVytauto Didžiojo universitetasŽemės ūkio akademij

Scots pine (pinus sylvestris l.) radial growth in vicinity of pollution source “Achema”

Vytauto Didžiojo universitetasŽemės ūkio akademij

Dendrochronological research of scots pine (Pinus sylvestris L.) radial growth invicinity of industrial pollution

The aim of this research is to investigate changes in the annual radial increment of Scots pine (Pinussylvestris L.) in the vicinity of intensive (3–10 km) and moderate (11–20 km) industrial pollution duringdifferent growth periods (growth promotion, inhibition, and recovery). Low level of emission was benefi-cial for tree growth during the growth promotion period, and the annual radial increment in the zones ofintensive and moderate pollution increased by approximately 15–25% and 10%, respectively. Severe losswas reported to forests during the growth inhibition period when nitrogen and sulphur dioxide emis-sions were 37–40 thousand (thou.) tons per year. About 40–45% tree radial increment loss was observedin the stands closest to the pollution source, and 15–20% loss was observed for the most distant stands.The stabilization of radial growth decrease and the beginning of recovery of damaged stands began in1988–1992, when the annual amount of industrial emissions and environmental pollution were consid-erably reduced. The stabilization of radial growth and the initiation of recovery after pollution reductionwere high for the most damaged stands. Their radial increment was stable and close to that of the controlstands in 2000–2011. Stands with less damage growing further from the pollution source were recoveredearlier, and their radial increment stabilized near the control increment in 1995–1999. The results of linearregression analysis demonstrated that the impact of pollution is different for stands growing at differentdistances from the plant, and the impact decreases with distance (R2= 0.78 and R2= 0.75, respectively;p < 0.05)Aplinkotyros katedraVytauto Didžiojo universitetasŽemės ūkio akademij

Indirect evidence of genetic tolerance to industrial pollution in Scots pine

Vytauto Didžiojo universitetasŽemės ūkio akademij

Changes of ground vegetation and tree-ring growth after surface fires in scots pine forests

The influence of low-intensity surface fires were investigated on the development of ground vegetation and tree growth in Scots pine (Pinus sylvestris) stands on sandy soils. The study was conducted in eastern part of Lithuania (55°35'N, 26°07'E). The annual investigations in 1-4-year-old burned sites show that low intensity surface fires mostly affected above-ground part of ground vegetation. Surface fires have destroyed above-ground part of ground vegetation cover, but it began to recover in the subsequent years. Within 3-4 years burned sites have had even higher number of species and ground vegetation coverage than in unbumed sites. The pioneer herb species and also dwarf shrubs, mainly Vaccinium myrtillus, were spread out. The recovery of moss cover was still non-significant. Investigations show, that low intensity surface fires didn't affect annual radial incrementVytauto Didžiojo universitetasŽemės ūkio akademij