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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.
11

Možnosti uplatnění chrastice rákosovité pro energetické účely / A possibilities of use of Phalaris arundinacea for energetic utilisation

VACEK, Martin January 2018 (has links)
The aim of my thesis was to compare selectid allotment, Botanical composition of allotmnet and prortion were monitored. Assessment of medium water content in soil. For parametrs of burning was to find number of fertile and sterile culm. In literal research are summarized common data about biomass and particular grass used for energetic purposes. Detailed description of reed canary grass and its description, agrotechnology and harvest. It is also important to mention processing of biomass in to the shape briquet and pelets. In the last part of research is description of burning device for used biomass. The practice part description to optain sample particular lokalities and these results and compares them.
12

First season effects of managed flooding on the invasive species Phalaris arundinacea L. and shoreline vegetation communities in an urban wetland

Jenkins, Noah John 01 January 2005 (has links)
Recent management efforts in the Smith and Bybee Lakes Wildlife Area (SBL), a 700-ha preserve in north Portland, Oregon, have included using a water control structure to suppress invasive reed canarygrass (Phalaris arundinacea L.) by flooding during spring and early summer growth periods. For the first year of managed flooding, I sought to determine: (a) the extent and distribution of reed canarygrass at SBL; (b) the effectiveness of the change in water level at suppressing reed canarygrass; and ( c) the effects of the change in water level on other plant species. I established 30 vegetation transects throughout SBL before completion of the water control structure. These transects were randomly distributed, placed perpendicularly to the shorelines of the wetlands, and had a cumulative length of 3.1 km. I measured vegetation on the transects in autumn 2003 and autumn 2004 using the line intercept method at 10-cm intervals. I surveyed the transects to generate elevation profiles, accurate to 0.15 cm, to determine depth and duration of flooding, which I correlated with vegetative changes. I also monitored inundation depth, growth, and phenological response of individual stands of reed canarygrass during the 2004 growing season.
13

Žolinių augalų panaudojimas kietajam biokurui / Herbal plants use for solid biofuel

Navadvorskytė, Justina 04 February 2013 (has links)
Šio magistro baigiamojo darbo tikslas buvo ištirti trijų energetinių žolinių augalų biometrines bei energetines savybes ir jas palyginti tarpusavyje. Augalai buvo auginami lauko sąlygomis, kiekvieną augalą tręšiant skirtingomis mineralinio azoto normomis (N0 – kontrolė, N60 – 200 kg ha-1 ir N120 – 400 kg ha-1). Buvo tiriami pagrindiniai biometriniai rodikliai: augalų aukštis, augalų stiebų skaičius, sausoji biomasė, chlorofilo indeksas. Taip pat ištirtas pasirinktų augalų šilumingumas, peleningumas, pagrindiniai elementai (C, H, N, S, O) bei šalutiniai elementai (K, Ca, Mg, P, Al, Si, S), taip pat sunkieji metalai. Visų augalų energetinės savybės palygintos tarpusavyje. Vertinant gautus duomenis, tinkamiausi žoliniai augalai biokurui yra sida ir drambliažolė, kadangi jų peleningumas yra mažiausias. Tačiau nendrinio dryžučio, nors ir išsiskyrė didesniu peleningumu, šilumingumas buvo didžiausias. Cheminės sudėties analizės metu buvo nustatyta, jog papildomas tręšimas azotinėmis trąšomis įvairių elementų kiekiui augaluose didelės įtakos neturėjo, tačiau vertinant šalutinių elementų kiekį augaluose pastebėta tai, jog kai kurių cheminių elementų padidėjimą galėjo lemti ir augalų augimo vieta (atvira pieva, šalia žvyrkelio, šalia kelio, šalia dirbamo lauko ir pan.). / This master's thesis was to analyze three energy plant grass biometric and energy properties and to compare them with each other. Plants were grown in field, every plant fertilized with different rates of nitrogen (N0 - control, N60 - 200 kg ha-1 and N120 - 400 kg ha-1). It was investigated the main biometric parameters: plant height, plant stems, dry biomass and chlorophyll index. Also plants calorific value, ash content, the main elements (C, H, N, S, O) and minor elements (K, Ca, Mg, P, Al, Si, S) and heavy metals. Plant‘s energy properties were compared with each other. Evaluating the data, the optimum herbaceous plant for biofuels are sida and Miscanthus as their ash content is lowest. Reed canary grass calorific value was highest, but it stood higher ash content too. Chemical composition analysis showed that the additional nitrogen fertilization had no major impact of the various elements in plants, but by assessing the amount of elements in plants is noticeable that plant growth and position may impact some chemical elements increase (open meadow, near the gravel, next to the road, arable land, etc.).
14

Žolinių augalų panaudojimas kietajam biokurui / Herbal plants use for solid biofuel

Navadvorskytė, Justina 04 February 2013 (has links)
Šio magistro baigiamojo darbo tikslas buvo ištirti trijų energetinių žolinių augalų biometrines bei energetines savybes ir jas palyginti tarpusavyje. Augalai buvo auginami lauko sąlygomis, kiekvieną augalą tręšiant skirtingomis mineralinio azoto normomis (N0 – kontrolė, N60 – 200 kg ha-1 ir N120 – 400 kg ha-1). Buvo tiriami pagrindiniai biometriniai rodikliai: augalų aukštis, augalų stiebų skaičius, sausoji biomasė, chlorofilo indeksas. Taip pat ištirtas pasirinktų augalų šilumingumas, peleningumas, pagrindiniai elementai (C, H, N, S, O) bei šalutiniai elementai (K, Ca, Mg, P, Al, Si, S), taip pat sunkieji metalai. Visų augalų energetinės savybės palygintos tarpusavyje. Vertinant gautus duomenis, tinkamiausi žoliniai augalai biokurui yra sida ir drambliažolė, kadangi jų peleningumas yra mažiausias. Tačiau nendrinio dryžučio, nors ir išsiskyrė didesniu peleningumu, šilumingumas buvo didžiausias. Cheminės sudėties analizės metu buvo nustatyta, jog papildomas tręšimas azotinėmis trąšomis įvairių elementų kiekiui augaluose didelės įtakos neturėjo, tačiau vertinant šalutinių elementų kiekį augaluose pastebėta tai, jog kai kurių cheminių elementų padidėjimą galėjo lemti ir augalų augimo vieta (atvira pieva, šalia žvyrkelio, šalia kelio, šalia dirbamo lauko ir pan.). / This master's thesis was to analyze three energy plant grass biometric and energy properties and to compare them with each other. Plants were grown in field, every plant fertilized with different rates of nitrogen (N0 - control, N60 - 200 kg ha-1 and N120 - 400 kg ha-1). It was investigated the main biometric parameters: plant height, plant stems, dry biomass and chlorophyll index. Also plants calorific value, ash content, the main elements (C, H, N, S, O) and minor elements (K, Ca, Mg, P, Al, Si, S) and heavy metals. Plant‘s energy properties were compared with each other. Evaluating the data, the optimum herbaceous plant for biofuels are sida and Miscanthus as their ash content is lowest. Reed canary grass calorific value was highest, but it stood higher ash content too. Chemical composition analysis showed that the additional nitrogen fertilization had no major impact of the various elements in plants, but by assessing the amount of elements in plants is noticeable that plant growth and position may impact some chemical elements increase (open meadow, near the gravel, next to the road, arable land, etc.).
15

Pěstování vybraných energetických plodin výnosové parametry / Growing of energy crops - yield parameters

NĚMEC, Václav January 2014 (has links)
Thesis deals with renewables resources, potential of biomass and plants phytomass. We focused on the cultivation of selected energy crops, as perennial grasses Elymus elongatus (subsp. ponticus, cv. Szarvasi-1), reed canary grass, miscanthus sinensis and annual crops of maize and sorghum. The practical part is aimed to the establishment of small plot trials with a variety Szarvasi-1, reed canary grass and miscanthus. We described the methods of field experiment establishing with crop Szarvasi-1 of their treatment and harvest. The results of our own experiments we compared with the literature data. The last part deals with the economy of growing selected crops.
16

Invasive Reed Canary Grass (Phalaris arundinacea) and Carbon Sequestration in a Wetland Complex

Bills, Jonathan S. 16 January 2009 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Terrestrial carbon sequestration is one of several proposed strategies to reduce the rate of carbon dioxide (CO2) accumulation in the atmosphere, but the impact of plant invasion on soil organic carbon (SOC) storage is unclear. The results of past studies are often confounded by differences in vegetation and environmental conditions. Reed canary grass (Phalaris arundinacea) is an herbaceous species that invades riparian fringes and wetlands throughout North America, including Beanblossom Bottoms – a wetland complex in south-central Indiana. Because of the prolific growth of P. arundinacea, it was hypothesized that significant alterations in SOC pools and dynamics would occur at invaded sites within the wetland complex. To test this hypothesis, study plots were established in areas colonized either by native herbaceous species or by P. arundinacea. Above and below-ground biomass were collected at the middle and end of the growing season and were analyzed for cellulose, lignin, acid detergent fiber, total phenolics, and organic carbon and nitrogen concentration. Soil samples were analyzed for SOC and nitrogen, bulk density, pH, and texture. The biomass of Scirpus cyperinus – a native wetland species was found to contain significantly (P < 0.05) more lignin (168 g kg-1 versus 98 g kg-1) and phenolics (19 g kg-1 versus 3 g kg-1), and had a higher C to N ratio (28 versus 20) than P. arundinacea biomass, suggesting greater recalcitrance of S. cyperinus tissues compared to P. arundinacea biomass. Results of a laboratory incubation study were consistent with the residue biochemistry data and showed that S. cyperinus biomass degraded at much slower rates than the biomass of P. arundinacea. However, measurements of SOC pools (0-30 cm) showed larger pools under P. arundinacea (25.5 Mg C ha-1) than under stands of S. cyperinus (21.8 Mg C ha-1). Likewise, SOC stocks under stands of mixed native vegetation were significantly (P < 0.05) smaller (18.8 Mg C ha-1) than in areas invaded by P. arundinacea. Biomass of the mixed native vegetation was also considered more recalcitrant than that of P. arundinacea based on residue biochemistry. Therefore, contrary to the study hypothesis, residue quality was not a good predictor of SOC stocks in the wetland soils. Thus, it appears that traditional laboratory assessments of biomass recalcitrance and decomposition do not accurately simulate the various biological interactions occurring in the field.
17

Systematisk bedömning av våtmarksväxter som substrat för biogasproduktion

Haglund, Emelie January 2014 (has links)
Två miljöproblem idag är ökade koncentrationer av växthusgaser i atmosfären och övergödning. Därför är två utmaningar att reducera utsläppen av växthusgaser och flöden av näringsämnen. Ytterligare en utmaning är att trygga energiförsörjningen i en värld där efterfrågan på energi ökar. Nya förnybara energikällor behöver utvecklas både för att trygga energiförsörjningen men även för att minska användandet av fossil energi. En förnybar energikälla är biogas som kan användas till el, värme och fordonsgas. Det förutspås att substrat för biogasproduktion kommer vara en bristvara i framtiden, därför behöver nya substrat utvärderas. Våtmarksväxter är ett alternativt substrat för biogasproduktion och utvärderades i den här studien. Våtmarker och dess växter är intressanta att studera eftersom de kan reducera koncentrationen näringsämnen som når sjöar och hav och kan därför bidra till att minska problemen med övergödning.    Studien genomfördes inom ett projekt vid Biogas Research Center och var en litteraturstudie med studie av ett fall. Metoden som användes har arbetats fram i projektet och är en multikriteriaanalys, (MCA), vilket innebär att det är flera olika områden som studeras. Områdena tar hänsyn till biologiska, ekonomiska, kemiska, miljömässiga och tekniska aspekter. För att strukturera upp informationen användes en matris som bestod av de olika huvudområdena som studerades. För att tydliggöra möjligheter och hinder gjordes en semi-kvalitativ bedömning av varje huvudområde.   Fallet som studerades var en våtmark i odlingslandskapet. Våtmarken är 5 ha och återskapades för några år sedan för att fungera som kväve- och fosforkälla. Det finns ingen växtlighet i våtmarken eftersom den är relativt ny. De växter som studerades under studien var därför växter som är tänkbara att växa i våtmarken i framtiden. Växterna som studerades var vass, rörflen och bredkaveldun. I våtmarken finns möjlighet att reglera vattennivån och därmed tömma den på vatten för att underlätta skörd.   Resultatet visade att den teknik som finns idag för skörd och sönderdelning behöver utvecklas eftersom den inte motsvarar de krav som ställs. Det finns olika tekniker för rötning och eftersom växterna har hög torrsubstanshalt är torrötning att föredra eller ett tvåstegssystem där första steget är torrötning. En våtmark ger en relativt liten mängd biomassa och därför passar det bättre att röta växterna tillsammans med andra substrat till exempel på en gårdsbiogasanläggning.   Våtmarksväxter är inte godkända substrat för certifiering av biogödsel, vilket kan vara ett hinder. Biogödseln har även ett lågt värde eftersom växterna innehåller låg halt näringsämnen. Våtmarker reducerar mängden näringsämnen och skörd kan bidra till att retentionen av fosfor ökar. Samtidigt avger våtmarker metan och lustgas som påverkar växthuseffekten.  Idag finns det ingen ekonomisk lönsamhet att skörda våtmarker. Ett system där ersättning fås för miljönyttan som skörd ger är ett alternativ för att öka lönsamheten. / Two environmental problems today are the increased concentrations of greenhouse gases in the atmosphere and eutrophication.  Therefore, two challenges are reducing greenhouse gas emissions and fluxes of nutrients. Another challenge is to secure the energy supply in a world where energy demand is increasing. New renewable energy sources need to be developed both to secure the energy supply, but also to reduce the use of fossil energy. A renewable energy source is biogas that can be used for electricity, heating and as vehicle fuel. It is predicted that substrate for biogas production will be a limitation in the future, therefore, new substrate need to be evaluated. Wetland plants are an alternative substrate for biogas production and evaluated in this study.  Wetlands and it is plants are interesting to study because they can reduce the concentration of nutrients and therefore help to reduce the problem of eutrophication.  The study was performed within a project at Biogas Research Center and was a literature study with the study of a case. The method used has been developed in the project and is a Multi Criteria Assessment (MCA), which means that there are several different areas being studied. Areas taking into account the biological, economic, chemical, environmental and technological aspects. In order to structure the data, a matrix consisting of the different key areas was used. To clarify the opportunities and obstacles a semi-qualitative assessment was done for each key area. The case studied was a wetland in an agricultural landscape. The wetland is 5 ha and was constructed a few years ago to work as nitrogen and phosphorous trap. There is no vegetation in the wetland because it is relatively new. The plants that were studied during the study was therefore plants that are potential to grow in the wetland in the future. The studied plants were reed, reed canary grass and cattail. In the wetland it is possible to regulate the water and thereby drain the water to facilitate harvesting.   The results showed that the technology available today for the harvesting and chopping needs to be developed because it does not meet the required standards. There are various techniques for digestion, but since the dry matter is high for the plants dry fermentation is preferable, or a two-stage system in which the first step is dry digestion. A wetland provides a relatively small amount of biomass and therefore it is better to co-digest the plants on a farm biogas plant.  Wetland plants are not approved substrates for certification of bio fertilizer, which can be an obstacle. The bio fertilizer also has a low value because the plants contain low levels of nutrients.Wetlands reduce the amount of nutrients and harvest of wetland plants contributes to the retention of phosphorus increases. Wetlands emit methane and nitrous oxide that affect global warming.Today, there is no economic viability of harvesting wetlands. A system in which compensation is obtained for the environmental benefit that harvest provides is an option to increase profitability.
18

Environmentální aspekty pěstování energetických plodin - produkce CO2eq / Environmental aspects of energy crops growing - production of CO2eq

PÍSAŘÍK, Martin January 2014 (has links)
This thesis deals with the partial evaluation of the life cycle of three kinds of power plants, particularly flint corn ( Zea mays L.) , reed canary grass ( Phalaris arundinacea L.) , Szarvazi I ( Agropyron elongatum L.) and their environmental impact during their cultivation. As an evaluation framework was used seedbed preparation time from the first year to the last harvest after ten years growing cycle. To calculate the emissions of greenhouse gases has been used software tool SimaPro . The aim was to find out how much greenhouse gas emissions (kg CO2eq per 1 kg of dry matter ) is created in the cultivation of selected power plants and compare that plant is from an environmental point of view the most environmentally friendly. The total emission load produced during the life cycle of corn is sown CO2eqv 0.199210 kg per 1 kg of dry matter , with reed rákosovité CO2eqv 0.182075 kg per 1 kg of dry matter. I Szarvasi is from an environmental point of view the most friendly CO2eqv produces 0.110232 kg per 1 kg of dry matter.
19

Enhancing herbicide efficacy on reed canary grass <i>(Phalaris arundinacea)</i> by testing a plant growth hormone, application times, and herbicide type

Fong, Denise Lynn 28 May 2013 (has links)
No description available.
20

Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary

Kidd, Sarah Ann 08 June 2017 (has links)
In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (<2.5 m) recovered native plant cover within 3-6 years post-tidal reconnection, while high marsh elevation zones (>2.5 m) remained dominated by nonnative species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was ii hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and nonnative plant community development and resilience.

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