Thesis (M.Inst.Agrar. (Animal Production (Animal and Wildlife Sciences)) -- University of Pretoria, 2009. / Abstract in English. Includes bibliographical references.

Agricultural soils in Nova Scotia are usually limed in order to raise soil pH to ensure optimum availability of soil nutrients. Wood ash, produced by burning wood-based fuels, is promoted as a substitute for agricultural lime. This study individually assessed two wood ash sources available to Nova Scotia producers through on-farm sampling as well as greenhouse bioassay and incubation experiments. The variables measured were soil pH, plant-available and total element concentrations in soil, total element concentrations in above ground plant tissue, botanical composition and pasture condition scores (PCS). Soil pH was significantly increased after the application of wood ashes, however the effect was short-lived for one ash (NewPage). Agricultural lime was the most effective at increasing pH. Total soil concentrations of Al, Cr, K and Na remained elevated one year after ash application to NewPage sites. Brooklyn Power ash contained excessive levels of Zn, Cd, Pb and As.

The majority of South African household live in poverty with a limited variety of foods available in their home. In most rural villages domestic poultry plays an important role in improving household food security, but is limited by shortage of feed and high feed costs. Using non-conventional feed ingredients in poultry diets may ease the situation of malnutrition in rural populations, providing the family with high quality animal protein at more affordable prices. Macadamia oil cake meal (MOCM) is an inexpensive by-product from the macadamia oil industry of the Limpopo Province. Although it is relatively high in crude protein (20-25%), MOCM has never been considered as a feed ingredient for poultry feeds. The high and varying fibre content (up to 25%, depending on the extrusion method applied) of MOCM may render it unsuitable as an ingredient for high producing poultry such as broilers. The question, however, arouse whether the inclusion of MOCM in the growing diet of meat-producing chickens typically found in rural areas, would be cost-effective. Calcium (Ca) in poultry rations is usually supplied as calcium carbonate from limestone. Wood ash (WA) from fireplaces at homestead in rural villages was found to be rich in Ca (approximately 26%) and has the potential of being a free and readily available Ca supplement that could easily be added to the diet. The purpose of this study was to evaluate the effects of MOCM and WA as alternative feed ingredients in growth rations for chickens in rural areas. New Hampshire chickens were randomly divided into eight treatment groups with four replicates per treatment and twelve chicks in each replicates. The chicks were housed in an environmentally controlled broiler house from day-old to 15-weeks of age. Four diets were formulated, one without MOCM and the other three containing different levels of MOCM, viz. 10, 50 and 100% plus salt and a trace nutrient mixture. Each of these treatments was split in two with one receiving limestone (CaCO3) and the other WA, as Ca sources, giving eight treatments in total. All the treatments received diets with a Ca level close to 1 %. Parameters measured on weekly basis were body weight (BW), feed intake (FI), and body weight gain (BWG) and feed conversion efficiency (FCE) was determined. The analysis of the carcass composition and tibia bone strength was done at the end of the 15 week period. An analysis of variance with the ANOVA model (SAS) was used to determine the significance between different treatments for the balanced data. Significance of difference (5%) between means was determined by multiple comparisons using Tukey t-test. The treatment of 100% MOCM was terminated at eight weeks since the chickens had retarded growth and low body weight gains, demonstrating that the 100% MOCM diet both with and without Ca were not feasible. The BW and feed intake of the diet of 100% MOCM plus WA was, however,significantly higher than the diet of 100% MOCM plus lime. However, the inclusion level of up to 50% MOCM had no significant differences in (muscle and fat), except for FI, BWG and FCE between treatment diets. In conclusion, the results prove that MOCM can be added to the ration at a 10% concentration level without any adverse effect on growth. Higher inclusion levels of MOCM might also be beneficial,especially when included at an older age of the bird. Wood ash proved to be an efficient Ca source, as the substitution of limestone with WA showed no negative effect on the tibia bone parameters measured. Copyright / Dissertation (MInstAgrar)--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted

Made available in DSpace on 2014-12-17T14:48:13Z (GMT). No. of bitstreams: 1 FellipeCACM_DISSERT.pdf: 1867444 bytes, checksum: bdeaf70a3884fde7d06961686d3bb1db (MD5) Previous issue date: 2012-12-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / With the increase in cement consumption, it has quickly become one of the inputs most consumed by mankind over the last century. This has caused an increase in CO2 emissions, as cement production releases large quantities of this gas into the atmosphere. Adding this fact to the growing consciousness of environmental preservation, it has led to a search for alternatives to cement to complement its derivatives, in the form of waste materials like the ashes. This research aimed to analyze the properties of mortars in fresh and hardened state with partial replacement of Portland cement by residual algaroba wood ash (CRLA) potteries produced by the state of Rio Grande do Norte. The CRLA was collected and sieved, where part of it was ground and characterized in comparison with that just sifted, being characterized according to its chemical composition, grain size, fineness, density, bulk density and index of pozzolanic activity. It was found that the wood ash does not act as pozzolan, and grinding it has not changed its characteristics compared to those just sifted, not justifying its use. Two traces were adopted for this research: 1:3 (cement: fine sand) and 1:2:8 (cement: hydrated lime: medium sand); both in volume, using as materials the CRLA just sifted, CP II F-32 Portland cement, CH-I hydrated lime, river sand and water from the local utility. For each trace were adopted six percentages of partial replacement of cement for wood ash: 0% (control) 5%, 7%, 10%, 12% and 15%. In the fresh state, the mortars were tested towards their consistency index and mass density. In the hardened state, they were tested towards their tensile strength in bending, compressive strength and tensile adhesion strength, and its mass density in the hardened state. The mortar was also analyzed by scanning electron microscopy and X-ray diffraction. Furthermore, it was classified according to NBR 13281 (2005). The results showed that up to a content of 5% substitution and for both traces, the residual algaroba wood ash can replace Portland cement without compromising the mortars microstructure and its fresh and hardened state / Com o aumento do seu consumo, o cimento se tornou rapidamente um dos insumos mais consumidos pela humanidade no ?ltimo s?culo. Isso desencadeou um aumento das emiss?es de CO2, uma vez que a produ??o do cimento libera na atmosfera grandes quantidades deste g?s. Somando este fato ao crescente pensamento da preserva??o ambiental, passou-se a buscar alternativas ao cimento, na forma de res?duos, para complementar os seus derivados, sendo uma delas as cinzas. Este trabalho teve como objetivo analisar as propriedades, no estado fresco e endurecido, de argamassas com substitui??o parcial do cimento Portland pela cinza residual de lenha de algaroba (CRLA) produzida pelas olarias do RN. A CRLA foi recolhida e peneirada, onde parte dela foi mo?da e caracterizada em compara??o com a apenas peneirada, sendo caracterizadas quanto a sua composi??o qu?mica, granulometria, finura, massa espec?fica, massa unit?ria e ?ndice de Atividade Pozol?nica. Avaliou-se que a cinza n?o atua como pozolana e que ela mo?da pouco variou em rela??o a apenas peneirada, injustificando seu uso. Adotou-se para este trabalho dois tra?os, sendo 1:3 (cimento : areia fina) e 1:2:8 (cimento : cal : areia m?dia), ambos em volume, usando-se como materiais a CRLA apenas peneirada, o cimento Portland CP II F-32, a cal hidratada CH-I, areia de rio e ?gua da concession?ria local. Para cada tra?o foram adotados percentuais de substitui??o parcial do cimento pela cinza, sendo eles 0% (refer?ncia), 5%, 7%, 10%, 12% e 15%. No estado fresco, as argamassas foram ensaiadas com rela??o ao seu ?ndice de consist?ncia e ? densidade de massa. No estado endurecido, foram ensaiadas com rela??o ? sua resist?ncia ? tra??o na flex?o, ? compress?o e de ader?ncia ? tra??o, e ? sua densidade de massa no estado endurecido. Elas foram tamb?m analisadas por microscopia eletr?nica de varredura e por difra??o de Raios-X. Al?m disso, as argamassas foram classificadas conforme a NBR 13281 (2005). Os resultados encontrados mostraram que, at? um teor de 5% de substitui??o e para ambos os tra?os, pode-se substituir o cimento pela cinza residual de lenha de algaroba sem comprometer as argamassas microestruturalmente e no seu estado fresco e endurecido

Made available in DSpace on 2016-12-08T17:19:28Z (GMT). No. of bitstreams: 1 Valeria Bennack.pdf: 3581807 bytes, checksum: fd498cfd4c0e26a27526c03e8a00fd60 (MD5) Previous issue date: 2016-02-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Economic and environmental issues are directly related to industrial activities, and consume natural resources, generate waste that can overload the environment. This work aims to analyze the feasibility of waste reuse (wood ash) from the combustion of the timber industry in the manufacture of cement products in the construction process. In the first stage was carried out the characterization of the aggregates and further characterization of the residue by physical testing, chemical, mineralogical, Morphological, thermal and environmental. In the second stage, carried out in the laboratory the effects of the added substitution kid in concrete production by residues in 10% ratios and 20% were studied in consistency testing compressive strength, as well as the morphological difference was evaluated its structures for analysis of electron microscopy. In the final stage, held in specialized industry in manufacturing of cement artifacts were produced concrete interlocking blocks with replacement of fine aggregate by waste in the same proportions of testing with concrete. Comparative analysis of compressive strength and electron microscopy were also made at this stage. Results indicate the possibility of reusing waste (wood ash) in the manufacture of cementitious products. / As questões econômicas e ambientais estão diretamente relacionadas às atividades industriais que, além de consumir recursos naturais, geram resíduos que podem sobrecarregar o meio ambiente. Este trabalho tem como objetivo analisar a viabilidade do reaproveitamento de resíduo (cinza de madeira) proveniente do processo de combustão da indústria madeireira na fabricação de produtos cimentícios da construção civil. Na primeira fase foi realizada a caracterização dos agregados e na sequência a caracterização do resíduo através de ensaios físico, químico, mineralógico, morfológico, térmico e ambiental. Na segunda fase, realizada em laboratório, estudou-se os efeitos da substituição do agregado miúdo na produção de concreto pelos resíduos em proporções de 10% e 20% nos ensaios de consistência, de resistência à compressão, bem como foi avaliada a diferença morfológica de suas estruturas em análises de microscopia eletrônica. Na fase final, realizada em indústria especializada em confecção de artefatos de cimento, foram produzidos blocos intertravados de concreto com substituição do agregado miúdo pelos resíduos nas mesmas proporções dos ensaios realizados com concreto. Análises comparativas de resistência à compressão e microscopia eletrônica também foram realizadas nesta etapa. Resultados indicam a possibilidade de reutilização de resíduo (cinza de madeira) na fabricação de produtos cimentícios.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-31T14:49:26Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao Mestrado 2016_Lupercio_ed_FINAL_3.pdf: 4260976 bytes, checksum: 7609f90da476d73ec08d04fc64831f71 (MD5) / Made available in DSpace on 2017-07-31T14:49:26Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao Mestrado 2016_Lupercio_ed_FINAL_3.pdf: 4260976 bytes, checksum: 7609f90da476d73ec08d04fc64831f71 (MD5) Previous issue date: 2016-03-11 / A utilização de resíduos nos sistemas construtivos favorece a política de preservação do meio ambiente contribuindo na redução do descarte de resíduos sólidos. A lenha de Algaroba (Prosopis Juliflora) utilizada como fonte de energia térmica para geração de vapor, o qual é gerado através da queima da lenha em uma fornalha que gera calor para uma caldeira, gera uma grande quantidade de cinzas. Estas cinzas se descartadas de forma inadequada, ocasionam sérios problemas ambientais. A utilização dessas cinzas, como matéria-prima para estabilizar o solo com adição de cimento (solo-cimento) contribuirá com o desenvolvimento sustentável, minimizando o descarte inadequado deste resíduo sólido no meio ambiente, reduzindo o impacto ambiental, além de tornara produção de tijolos ecológicos economicamente viáveis. O objetivo deste trabalho foi produzir tijolos ecológicos de solocimento utilizando da cinza da lenha de Algaroba como material estabilizante do solo. Para isto foram realizados cinco traços com diferentes teores de cinza de 0 % (referência), 10%, 30 %, 40 %, e 50 %. Estes percentuais são referentes à substituição parcial do cimento pela cinza. Os tijolos fabricados com 10% de cinza apresentaram maior resistência à compressão simples e mantiveram-se dentro da norma. Os resultados de absorção de água indicaram que todas as amostras obtiveram valores médios menores que 20 % e valores individuais menores que 22 % de acordo com os valores exigidos pela norma NBR 10834 (ABNT, 1994). Os resultados mostram que é possível utilizar a cinza da lenha de Algaroba na subsstituição parcial do cimento para produzir tijolos de solo-cimento-cinza com o teor de 10% de cinza. / The utilization of waste in construction systems favors the environmental preservation policy, contributing in reducing solid waste. The Algaroba (Prosopis Juliflora), used as a thermal energy source to generate steam, which is generated by wood burning in a furnace that generates heat to a boiler, it generates a lot of ash. The se ashes are improperly discarded, causing serious environmental problems. The use of these ashes as a raw material to stabilizing soil with the addition of cement (soil-cement) will contribute for the sustainable development, minimizing improper disposal of solid waste in the environment, reducing environmental impact, besides making the production of ecological bricks economically viable. The objective of this work was to produce ecological bricks of soil-cement using ash mesquite (Prosopis Juliflora) as soil stabilizing material. For this, were done bricks with different contents ash: 0 % (reference), 10%, 30 %, 40 % and 50 %. These percentages refer to the partial replacement of cement by ash. The bricks manufactured with 10% gray have higher resistance to simple compression and remained within the standard. The results of water absorption indicates that all samples obtained average values lower than 20 % and single values lower than 22 %, in accordance with the values required by the standard NBR 10834 (ABNT, 1994). The results show that it is possible to use Algaroba wood ash in partial cement substitution to produce soil-cement-gray brick with the percentage of 10% wood ash.

The European Commission adopted the first action plan for the transition to a circular economy in 2015. As a result, the concrete industry’s goal is for all concrete produced in Sweden to be climate neutral by 2045. Cement production is the third-largest carbon dioxide emitter in Sweden and accounts for 90% of concrete’s carbon dioxide emissions. Thus, to lower the climate footprint of concrete, it is necessary to find alternatives to cement. The potential of the use of wood ash in cement as a supplementary cementitious material (SCM) has been investigated in several studies. Due to Sweden's nature and wood industry, a comprehensive study has been done to investigate the possibility of using wood ash as an SCM in Sweden based on availability and efficiency. This work aims to investigate the obstacles and driving forces that concrete producers face when transitioning to a circular economy by partially replacing cement with new potential SCMs. The aim is also to investigate the availability of wood ash generated in Sweden and account for the potential to be used as an SCM. Qualitative semi-structured interviews with open-ended questions were conducted to determine the obstacles and drivers that concrete producers in Sweden face when converting to a circular economy by partially replacing cement with new potential SCMs. The amount of ash produced in Sweden was estimated based on the value of ash content and the potential annual supply of wood fuels in Sweden. In addition, a literature review was performed to investigate the properties of wood ash. The economic and environmental aspects, as well as the fact that the supply of fly ash and slag is likely to decrease in the future form the main driving forces for concrete producers. The obstacles raised by the correspondents were the availability of SCMs, technical barriers, logistics, and standards. The amount of the annual production of wood ash in Sweden is estimated to be between 851 450 and 1 232 950 tons. The chemical characteristics of wood ash did not meet the requirements according to European standard (EN450-1). However, the reviewed articles indicated a potential for wood ash to be used as a supplementary cementitious material due to the indication of some hydraulic and pozzolanic activities. The combination of fly ash and wood ash in concrete is considered viable due to promising results based on mechanical strength. / EU-kommissionen antog den första handlingsplanen för omställningen till en cirkulär ekonomi 2015. Som ett resultat av detta är betongindustrins mål att all betong som används i Sverige ska vara klimatneutral år 2045. Cementindustrin är den tredje största koldioxidutsläpparen i Sverige och står för 90 % av betongens koldioxidutsläpp. För att sänka betongens klimatavtryck är det nödvändigt att hitta alternativ till cement. Potentialen för användningen av träaska i cement som ett alternativt bindemedel har undersökts i flera studier. Med hänsyn till Sveriges natur- och träindustri har en omfattande studie gjorts för att undersöka möjligheten att använda träaska som alternativ bindemedel i Sverige utifrån tillgänglighet och effektivitet. Arbetet syftar till att undersöka de hinder och drivkrafter som betongföretag möter vidövergången till en cirkulär ekonomi genom att delvis ersätta cement med nya alternativa bindemedel. Syftet är också att undersöka tillgången på träaska som genereras i Sverige och redogöra för potentialen att användas som ett bindemedel. Kvalitativa semistrukturerade intervjuer med öppna frågor genomfördes för att fastställa de hinder och drivkrafter som företag inom betongtillverkning i Sverige möter vid en omställning där cement ersätts delvis med nya bindemedel. Mängden aska som produceras i Sverige har uppskattats utifrån värden på askhalt och den potentiella årliga tillgången på trädbränslen i Sverige. Dessutom har en litteraturöversikt genomförts för att undersöka träaskans egenskaper. Drivkrafterna för en omställning till cirkulär ekonomi hos betongindustrier genom delvis ersättning av cement med nya alternativa bindemedel är de ekonomiska och miljömässiga aspekterna samt det faktum att tillgången på flygaska och slagg riskerar att sjunka i framtiden. Hindren som korrespondenterna tog upp var tillgången till alternativa bindemedel, tekniska barriärer, logistik och standarder. Mängden av den årliga produktionen av träaska i Sverige uppskattas mellan 851 450 och 1 232 950 ton. Kemiska egenskaper hos de undersökta träaskorna uppfyller inte kraven enligt europeisk standard (EN450-1). Litteraturöversikten visar dock en potential för träaska att användas som ett alternativt bindemedel till följd av en viss hydraulisk och puzzolanisk aktivitet. Kombinationen av flygaska och träaska i betong anses lönsam på grund av lovande resultat baserade på mekanisk hållfasthet.

In Sweden, utilisation of incinerator residues outside disposal areas is restricted by environmental concerns, as such residues commonly contain greater amounts of potentially toxic trace elements than the natural materials they replace. On the other hand, utilisation can also provide environmental benefits by decreasing the need for landfill and reducing raw material extraction. This thesis provides increased knowledge and proposes better approaches for environmental assessment of incinerator residue utilisation, particularly bottom ash from municipal solid waste incineration (MSWI).A life cycle assessment (LCA) based approach was outlined for environmental assessment of incinerator residue utilisation, in which leaching of trace elements as well as other emissions to air and water and the use of resources were regarded as constituting the potential environmental impact from the system studied. Case studies were performed for i) road construction with or without MSWI bottom ash, ii) three management scenarios for MSWI bottom ash and iii) three management scenarios for wood ash. Different types of potential environmental impact predominated in the activities of the system and the scenarios differed in use of resources and energy. Utilising MSWI bottom ash in road construction and recycling of wood ash on forest land saved more natural resources and energy than when these materials were managed according to the other scenarios investigated, including dumping in landfill. There is a potential for trace element leaching regardless of how the ash is managed.Trace element leaching, particularly of copper (Cu), was identified as being relatively important for environmental assessment of MSWI bottom ash utilisation. CuO is suggested as the most important type of Cu-containing mineral in weathered MSWI bottom ash, whereas in the leachate Cu is mainly present in complexes with dissolved organic matter (DOM). The hydrophilic components of the DOM were more important for Cu binding than previously understood. Differences were also observed between MSWI bottom ash DOM and the natural DOM for which the geochemical speciation models SHM and NICA-Donnan are calibrated. Revised parameter values for speciation modelling are therefore suggested. Additions of salt or natural DOM in the influent did not change the leachate concentration of Cu. Thus, although Cl and natural DOM might be present in the influent in the field due to road salting or infiltration of soil water, this is of minor importance for the potential environmental impact from MSWI bottom ash.This thesis allows estimates of long-term leaching and toxicity to be improved and demonstrates the need for broadening the system boundaries in order to highlight the trade-offs between different types of impact. For decisions on whether incinerator residues should be utilised or landfilled, the use of a life cycle perspective in combination with more detailed assessments is recommended. / QC 20100914

In Lithuania the energy production from the forest wood comprises up to 90% of the total biomass derived energy. Increasing use of wood fuel increases the removal of the plant essential nutrients from the ecosystem because the branches, tops and needles/leaves contain relatively higher amount of the nutrients than stems. If to compare with the removal of the stems-only, the nutrient losses from the forest ecosystem increase up to 5 times. One way to return nutrients to the ecosystem is to apply forest fuel waste – wood ash - as fertilizers. In this study the effects of the differential wood ash fertilization and ash fertilization in complex with nitrogen on the ground vegetation structure (species composition, abundance), biomass and chemical composition in Pinus sylvestris stands (forest type – Vaccinio-Pinetum) was estimated. For the first time, the long-term impact of nitrogen as well the influence of the high nitrogen doses on ground vegetation structure and abundance in Scots pine stands growing on infertile sandy soils (Haplic Arenosols) were studied in Lithuania. The spreading of the nitrophylous plant species in the ground vegetation in pine stands during 20 years period were detected. The role of the trees competition in the soil rhizosphere zone on ground vegetation was analysed. The following soil and ground vegetation parameters were estimated: soil moisture, pH and chemical composition, also the biomass of vascular plants, coverage, biomass and chemical... [to full text] / Lietuvoje iki 90% energijos gamybai naudojamos biomasės sudaro mediena. Iš miško išvežant visas miško kirtimo atliekas, o ne paliekant natūraliam suirimui, maisto medžiagų nuostoliai miško ekosistemoje padidėja iki 5 kartų. Kompensuojamasis miškų tręšimas medienos kuro pelenais – tai vienas iš būdų grąžinti maisto medžiagas į miško ekosistemą. Darbe įvertintas kompensuojamojo tręšimo medienos kuro pelenais diferencijuotas ir kompleksinis (kartu su azotu) poveikis brukninių pušynų gyvosios dirvožemio dangos struktūrai bei biomasės cheminei sudėčiai. Pirmą kartą Lietuvoje tiriamas ilgalaikio tręšimo azotu bei didelių azoto dozių poveikis brukninių pušynų, augančių nederlinguose smėlžemiuose, gyvosios dirvožemio dangos rūšių sudėčiai bei gausumui. Nustatytas foninių azoto iškritų sąlygotas nitrofilinių augalų rūšių išplitimas brukninių pušynų (Vaccinio-Pinetum) gyvojoje dirvožemio dangoje. Ištirtas miško ekosistemos edifikatorių konkurencinis poveikis rizosferoje: dirvožemio drėgniui, pH bei cheminei sudėčiai, žolių/krūmokšnių padengimui bei biomasei, gyvosios dirvožemio dangos dominanto bruknės (Vaccinium vitis-idea L.) biomasei bei biomasės cheminei sudėčiai. Atlikti tyrimai leidžia daryti išvadas, kad samanų rūšims tiek medienos kuro pelenų, tiek azoto poveikis yra neigiamas, tuo tarpu žolių/krūmokšnių rūšims – teigiamas. Visgi, azoto poveikis žolių/krūmokšnių rūšims priklauso ne tik nuo dozės, bet ir nuo patekimo į miško ekosistemą dažnio. Brukniniuose pušynuose... [toliau žr. visą tekstą]

Lietuvoje iki 90% energijos gamybai naudojamos biomasės sudaro mediena. Iš miško išvežant visas miško kirtimo atliekas, o ne paliekant natūraliam suirimui, maisto medžiagų nuostoliai miško ekosistemoje padidėja iki 5 kartų. Kompensuojamasis miškų tręšimas medienos kuro pelenais – tai vienas iš būdų grąžinti maisto medžiagas į miško ekosistemą. Darbe įvertintas kompensuojamojo tręšimo medienos kuro pelenais diferencijuotas ir kompleksinis (kartu su azotu) poveikis brukninių pušynų gyvosios dirvožemio dangos struktūrai bei biomasės cheminei sudėčiai. Pirmą kartą Lietuvoje tiriamas ilgalaikio tręšimo azotu bei didelių azoto dozių poveikis brukninių pušynų, augančių nederlinguose smėlžemiuose, gyvosios dirvožemio dangos rūšių sudėčiai bei gausumui. Nustatytas foninių azoto iškritų sąlygotas nitrofilinių augalų rūšių išplitimas brukninių pušynų (Vaccinio-Pinetum) gyvojoje dirvožemio dangoje. Ištirtas miško ekosistemos edifikatorių konkurencinis poveikis rizosferoje: dirvožemio drėgniui, pH bei cheminei sudėčiai, žolių/krūmokšnių padengimui bei biomasei, gyvosios dirvožemio dangos dominanto bruknės (Vaccinium vitis-idea L.) biomasei bei biomasės cheminei sudėčiai. Atlikti tyrimai leidžia daryti išvadas, kad samanų rūšims tiek medienos kuro pelenų, tiek azoto poveikis yra neigiamas, tuo tarpu žolių/krūmokšnių rūšims – teigiamas. Visgi, azoto poveikis žolių/krūmokšnių rūšims priklauso ne tik nuo dozės, bet ir nuo patekimo į miško ekosistemą dažnio. Brukniniuose pušynuose... [toliau žr. visą tekstą] / In Lithuania the energy production from the forest wood comprises up to 90% of the total biomass derived energy. Increasing use of wood fuel increases the removal of the plant essential nutrients from the ecosystem because the branches, tops and needles/leaves contain relatively higher amount of the nutrients than stems. If to compare with the removal of the stems-only, the nutrient losses from the forest ecosystem increase up to 5 times. One way to return nutrients to the ecosystem is to apply forest fuel waste – wood ash - as fertilizers. In this study the effects of the differential wood ash fertilization and ash fertilization in complex with nitrogen on the ground vegetation structure (species composition, abundance), biomass and chemical composition in Pinus sylvestris stands (forest type – Vaccinio-Pinetum) was estimated. For the first time, the long-term impact of nitrogen as well the influence of the high nitrogen doses on ground vegetation structure and abundance in Scots pine stands growing on infertile sandy soils (Haplic Arenosols) were studied in Lithuania. The spreading of the nitrophylous plant species in the ground vegetation in pine stands during 20 years period were detected. The role of the trees competition in the soil rhizosphere zone on ground vegetation was analysed. The following soil and ground vegetation parameters were estimated: soil moisture, pH and chemical composition, also the biomass of vascular plants, coverage, biomass and chemical... [to full text]