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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Amoniakinės taršos įtaka paprastosios pušies (Pinus sylvestris L.) spyglių hidrofobiškumo ir mezomorfiškumo dinamikai / Needle of Scots pine (Pinus sylvestris L.) hidrofobic and mezomorphic dynamics in the effect of ammonia pollution

Vilčinskas, Ramūnas 21 June 2010 (has links)
Magistro darbe tiriama paprastosios pušies (Pinus sylvestris L.) būklė amoniakinės taršos poveikyje. Darbo objektas – paprastoji pušis (Pinus sylvestris L.) – labiausiai paplitusi Lietuvoje, jautri užterštam orui medžių rūšis, augantys prie AB „Achema“ 0,5 km. spinduliu aplink gamyklą vakarų, šiaurės ir šiaurės rytų kryptimis ir Kačerginės pušyne. Darbo metodai – spyglių paviršių hidrofobiškumo tyrimas atliekamas šviesiniu mikroskopu, pagal Cape (1983) aprašytą metodiką. Mezomorfiškumo tyrimo metu tirti spyglių pjūviai šviesiniu mikroskopu. Darbo rezultatai. Vandens lašo sąlyčio su spyglio paviršiumi metodas pasirinktas, kaip santykinai nebrangus ir tikslus testas medžių būklei vertinti. Paprastosios pušies spyglių paviršiaus tyrimai parodė, kad spygliai pasižymėjo mažiausiais (p<0,05) sąlyčio kampais, t.y. didžiausiu paviršių sudrėkstamumu, palyginus su Kačerginės pušyno spygliais. Prie AB “Achema” augančių pušų augimo sezono eigoje pirmamečių spyglių ir vandens lašo sąlyčio kampai buvo 83-102°, o antramečių– 68-79°. Atlikti tyrimai rodo, kad dabartinė amoniakinė tarša blogina paviršių kokybę, didindama paviršiaus sudrėkstamumą, ant drėgno paviršiaus gali lengviau augti patogeniniai mikroorganizmai. Atliekant histologinį tyrimą taršai nustatyti spyglių audinių dydžiai ir santykiai nevienodos amoniakinės taršos poveikyje. Tyrimai nepateikė vienareikšmiško atsakymo apie mezomorfiškumo skirtumus tarp Kačerginės ir šalia AB "Achema" augančių pušynų. Pusamžių medynų... [toliau žr. visą tekstą] / Scots pine (Pinus sylvestris L.) state the effect of ammonia pollution was investigated in the work of master science. Object of the work – Scots pine (Pinus sylvestris L.) – the most common in Lithuanian territory, sensitive to air pollution tree species, growing in the vicinity of the nitrogen fertilizer factory in the west, north and north-east direction and control site. Method of the work – hydrophobicity of leaf surface, under light microscope according to Cape (1983) described the methodology. Investigate mezomorphic study needle incisions by light microscope. The results of the work. The investigation of water droplet contact angles is an unexpensive and accurate method used to evaluate the trees condition. The values of the contact angles of the water droplets on the surface of the needles were higher in control site. Near the nitrogen factory contact angles of the water droplets on the surface of current–year needles were 83-102 °, 1–year–old needles –68-79. Investigation showed, that present level nitrogen pollution might cause the erosion of the needle surface and more wettable surface might cause the development of pathogenic microorganisms. The aim of this study was to evaluate histological parameters of the needlles and tissues between sites with different ammonia concentration. Histological evaluation of the needles did not allow to detected changes in cross section parameters and defiance mesomorphic features growth. Current–year needle thickness was 0... [to full text]
2

Paprastosios pušies spyglių morfologinių ir fiziologinių savybių kitimas lietuvos lokalios taršos poveikyje / Changes of morphological and physiological parameters of the needles of Scots pine under influence of local pollution in Lithuania

Šedbaraitė, Jūratė 04 June 2005 (has links)
SUMMARY In the research work for Master degree the variance of morphological-physiological characteristics of the needles of Scots pine (Pinus sylvestris L.) growing in the vicinity of local pollution sources of Lithuania were investigated. Subject of research: Scots pine (Pinus sylvestris L.) growing near the largest industrial pollution sources in Lithuania: a cement factory, a nitrogen fertilizer factory and an oil refinery. Goals of the research: to estimate morphological and physiological features of the needles sampled from the pines growing at different distances from the largest industrial pollution sources. Methodology: the needle morphological features were determined by evaluating needle fluctuating length asymmetry and needle fluctuating mass asymmetry. The needle surface quality was evaluated by measuring contact angles of the water droplets and following the dynamics of water loss from excised needles. Research results: Significant differences were documented between the pine stands located at different distances from the cement factory. The needle asymmetry and surface data of the pine stand near the cement factory showed that the cement dust had a negative effect on the needle development and structure. The pine stand growing in the vicinity of the cement factory was characterised by increased needle asymmetry, faster water loss from the excised needles and increased surface wettability. No morphological and physiological changes as caused by air... [to full text]

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