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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.
41

Soil Genesis and Vegetation Response to Amendments and Microtopography in Two Virginia Coastal Plain Created Wetlands

Ott, Emily Thomas 12 June 2018 (has links)
Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goals. Compost rates of 112 Mg ha-1 are sufficient for short term establishment of wetland vegetation and hydric soil properties, but higher rates near 224 Mg ha-1 may be required for effects that last over 10 years. / Ph. D. / Wetlands are unique habitats that provide environmental benefits such as carbon storage but are often negatively affected by human disturbances such as urban development and road construction. When wetlands are constructed to mitigate natural wetland losses, it is important that they successfully provide the benefits of the wetlands they replace. Created wetlands have frequently not functioned like natural wetlands due to soil issues including low organic carbon (OC) and high soil density (BD). Organic matter (OM) amendments such as composted yard waste help created wetlands attain these functions quickly after construction compared to unamnded wetlands. The purpose of this study was to measure long-term (greater than 10 years) effects of OM treatments on soil and vegetation properties at two different created wetlands. The two wetlands were a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, compacted, non-tidal wetland created in 2002 (CCW). Previous soil data were compared to recent soil samples to detect changes in physical and chemical soil properties over time. At WWE, soils in pits accumulated more OM, were higher in carbon, lower in BD, and had greyer color than soils in mounds. Hydric soil field indicators developed from upland soil within four years after construction at WWE. There were no long term compost effects on soil properties compared to a fertilized control, but the compost rates used were low compared to other recommendations, and the wetland was constructed carefully to avoid compaction. There were much higher rates of compost applied at CCW, which produced lower BD, higher soil mass C, and higher tree biomass. We recommend applying OM and avoiding compaction during wetland construction. Ideal OM loading rate depends on wetland type (soil texture, hydrology) and mitigation goals. In the fine-textured, compacted wetland studied here, compost rates of 112 Mg ha⁻¹ are ideal for short term establishment of wetland vegetation and soil properties, but higher rates near 224 Mg ha⁻¹ may be required for long term effects.
42

Vers une meilleure estimation des stocks de carbone dans les forêts exploitées à Diptérocarpées de Bornéo / Towards better estimates of carbon stocks in Bornean logged-over Dipterocarp forests

Rozak, Andes 29 November 2018 (has links)
Les forêts tropicales constituent le principal réservoir de biodiversité et de carbone (C). Cependant, la plupart des forêts tropicales, en particulier les forêts de Bornéo en Asie du Sud-Est, subissent une pression intense et sont menacées par des activités anthropiques telles que l'exploitation forestière, l'industrie minière l’agriculture et la conversion en plantations industrielles. En 2010, la superficie des forêts de production de Bornéo était de 26,8 millions d’ha (environ 36% de la superficie totale de l’île, dont 18 millions ha (environ 24%) déjà exploités. Par conséquent, les forêts de production occupent donc une place importante à Bornéo et jouent un rôle essentiel dans la compensation des biens fournis et la maintenance des services écosystémiques, tels que la conservation du C et de la biodiversité.L’exploitation sélective réduit la biomasse aérienne et souterraine par l’élimination de quelques grands arbres, et augmente les stocks de bois mort par des dommages collatéraux. En créant des trouées dans la canopée, le microclimat dans les sous-étages et au sol change localement et accélèrent la décomposition de la litière et de la matière organique. L'importance des dégâts, de l'ouverture de la canopée et de la rapidité du rétablissement du C s'est avéré principalement liée à l'intensité de l'exploitation forestière. Cependant, les évaluations empiriques de l'effet à long terme de l'intensité de l'exploitation forestière sur l'équilibre du C dans les forêts de production restent rares.La présente thèse se concentre principalement sur l'évaluation de l'effet à long terme de l'intensité de l'exploitation forestière sur la séquestration de carbone dans une forêt à Diptérocarpées de Nord Bornéo (District de Malinau, Kalimantan Nord) exploitée en 1999/2000. Cinq principaux réservoirs de C, à savoir le C aérien dans les arbres vivants (AGC), le C souterrain dans les arbres vivants (BGC), le bois mort, la litière et le C organique du sol (SOC) ont été estimés le long d’un gradient d'intensité d'exploitation (0-57% de la biomasse perdue).Nos résultats ont montré que les stocks totaux de C, 16 ans après l'exploitation, variaient de 218 à 554 Mg C ha-1 avec une moyenne de 314 Mg C ha-1. Une différence de 95 Mg C ha-1 a été observée entre une faible intensité d'exploitation forestière (<2,1% de la biomasse initiale perdue) et une intensité d'exploitation élevée (>19%). La plus grande partie du C (environ 77%) était présente dans les arbres vivants, suivie par les stocks du sol (15%), les stocks de bois mort (6%) et une fraction mineure des stocks de litière (1%). L'empreinte de l'intensité de l'exploitation forestière était encore détectable 16 ans après l'exploitation et a été le principal facteur expliquant la réduction des AGC>20, BGC>20, du bois mort et des stocks de C et une augmentation du bois mort. L'intensité de l'exploitation expliquait à elle seule 61%, 63%, 38% et 48% des variations des AGC>20, BGC>20, du bois mort et des stocks de C totaux, respectivement. L'intensité de l'abattage a également réduit considérablement les stocks de SOC dans la couche supérieure de 30 cm. Pour l'ensemble des stocks de SOC (0-100 cm), l'influence de l'intensité de l'exploitation était encore perceptible, en conjonction avec d'autres variables.Nos résultats quantifient l'effet à long terme de l'exploitation forestière sur les stocks de C forestier, en particulier sur les AGC et les bois morts. L'intensité élevée de l'exploitation forestière (réduction de 50% de la biomasse initiale) a réduit les stocks totaux de C de 27%. La récupération de l'AGC était plus faible dans les parcelles d'intensité d'exploitation forestière élevée, ce qui suggère une résilience plus faible de la forêt à l'exploitation forestière. Par conséquent, une intensité d'exploitation forestière inférieure à 20%, devrait être envisagé afin de limiter l'effet à long terme sur les AGC et le bois mort. / Tropical forests are a major reservoir of biodiversity and carbon (C), playing a pivotal role in global ecosystem function and climate regulation. However, most of the tropical forests, especially Bornean forests in Southeast Asia, are under intense pressure and threatened by anthropogenic activities such as logging, mining industry, agriculture and conversion to industrial plantation. In 2010, the area of production forests in Borneo was 26.8 million ha (approx. 36% of the total land area of Borneo) including 18 million ha (approx. 24%) of logged forests. Production forests are thus emerging as a dominant land-use, playing a crucial role in trading-off provision of goods and maintenance of ecosystem services, such as C and biodiversity retention.Selective logging is known to reduce both above- and below-ground biomass through the removal of a few large trees, while increasing deadwood stocks through collateral damages. By creating large gaps in the canopy, microclimates in the understory and on the forest floor change locally speeding up the decomposition of litter and organic matter. The extent of incidental damages, canopy openness, as well as the speed of C recovery, was shown to be primarily related to logging intensity. However, empirical evaluations of the long-term effect of logging intensity on C balance in production forests remain rare.The present thesis aims to assess the long-term effect of logging intensity on C sequestration in a north Bornean Dipterocarp forests (Malinau District, North Kalimantan) logged in 1999/2000. Five main C pools, namely above-ground (AGC) and below-ground (BGC) carbon in living trees, deadwood, litter, and soil organic carbon (SOC) were estimated along a logging intensity gradient (ranging from 0 to 57% of initial biomass removed).Our result showed that total C stocks 16 years after logging, ranged from 218-554 Mg C ha-1 with an average of 314 Mg C ha-1. A difference of 95 Mg C ha-1 was found between low logging intensity (<2.1% of initial biomass lost) and high logging intensity (>19%). Most C (approx. 77%) was found in living trees, followed by soil (15%), deadwood (6%), and a minor fraction in litter (1%). The imprint of logging intensity was still detectable 16 years after logging, and logging intensity thus was the main driver explaining the reduction of AGC>20, BGC>20, deadwood, and total C stocks and an increase in deadwood. Solely, logging intensity explained 61%, 63%, 38%, and 48% of variations of AGC>20, BGC>20, deadwood, and total C stocks, respectively. Logging intensity also significantly reduced SOC stocks in the upper 30 cm layer. For total SOC stocks (0-100 cm), the negative influence of logging intensity was still perceptible, being significant in conjunction with other variables.Our results quantify the long-term effect of logging on forest C stocks, especially on AGC and deadwood. High logging intensity (50% reduction of initial biomass) reduced total C stocks by 27%. AGC recovery was lower in high logging intensity plots, suggesting lowered forest resilience to logging. Our study showed that maintaining logging intensity, below 20% of the initial biomass, limit the long-term effect of logging on AGC and deadwood stocks.
43

Productivity and nutrient relations of trees in deciduous forests differing in tree species diversity / Produktivität und Nährstoffhaushalt der Bäume in Laubwäldern unterschiedlicher Baumartendiversität

Jacob, Mascha 19 March 2009 (has links)
No description available.
44

Centrum odpočinku v Lavičkách / Center of Rest in Lavičky

Pospíšilová, Iveta January 2018 (has links)
The topic of this master´s thesis is a new building design of recreation centre in Lavičky and processing of project documentation for this building realization. This thesis is furthermore completed with two specializations. It deals specifically with a specialisation in the field of technical facilities of buildings – heating and air conditioning. The recreation centre is a complex of two units that will provide restaurant and accommodation services with leisure activities facilities. In one of the units there is designed an accommodation facility with smaller wellness area, in the other unit there is designed a restaurant. The estate where the units are located occurs in the north part of the village Lavičky. This locality is built up by family houses and apartment blocks. The architectural solution of the designed units follows on from the concept of simple country object where the object has the shape of rectangle ground plan and is roofed by typical saddle roof. The building of the restaurant and also the guest house is in the shape of rectangle and is roofed by double sheathed saddle roof with metal folded roofing in dark grey colour. As well it utilises modern elements of architecture as big window openings or dormers. The filling of the openings will be accomplished by wooden windows in natural shade. The façade of the units is designed in that way to match both unis together. It is solved by white façade paint in combination with cement splinter panels imitating wood or cement splinter panels in grey colour and is completed by outdoor wooden pergola or wooden storm porch. The wall base part is formed by mosaic façade in grey colour. The layout solution of the units follows on from operation requirements of the particular services and they are separated in space for customers and for operation space. In the unit of the guest house there are designed 9 suites with 22 beds. In the ground floor there is designed one suite for persons with reduced mobility and o
45

Vinařství / Winery

Štipčák, Martin January 2018 (has links)
The objective of the thesis is newly built winery in the wine cellars alley situated inVlkoš u Kyjova in the South Moravia Region. Capacity for wine production is around 180,000 litres. In the building are the tasting rooms and pension with the capacity of 30 people. The building has three floors and a partial basement. The winery is located on sloping land. The building is designed as a brick construction, where underground vertical structures are made of blocks permanent formwork Best and part above ground is made of ceramics blocks Porotherm. The horizontal structures are made of prestressed ceiling panels Spiroll above the production area and the rest is made of ceramics system Porotherm. The gable roof, the walkable and warm flat roof are used in the project. The main goal of diploma thesis is to draft a develop project documentation for building construction.
46

Polyfunkční dům / Mixed-use building

Navrátil, Jan January 2018 (has links)
The subject of this thesis is a new mixed-use building in the Brno part of Zábrdovice. The building will have one basement and six above-ground floors. In the ground floor will be located store and service of the bicycles and on the first floor there will be smaller space for rent. On the first to five floor there will be eleven flats. The main entrance to the building is designed from the southwest side of Koliště street. In the plot there will be a parking lock system for eleven cars. The access road to the parcel is from the east side. The mixed-use building is designed from a wall structural system. The basement will be made of monolithic reinforced concrete walls, and above-ground floors will be made of clay blocks. The floor structure will be made of cast-in-place reinforced slab. The mixed-use building will be warm flat green roof with extensive greenery.
47

Studentský dům / Student House

Lisá, Nikola January 2019 (has links)
The thesis is focused on elaboration of project documentation. The student house will be located in the city of Ostrava. The building has 4 above-ground floors with partial basement .The basement will for the most part serve as a technical facilities. On the first floor there will be rooms - reception, reception, office, bicycle room, café, small shop, gym, copy center, facilities and hygienic room. Residential units are located on 2 to 4 floors. There will be 26 residential units - single and double, total for 54 persons. Each residential cell has its own sanitary facilities and a kitchenette. The building is designed as a masonry system. The load-bearing masonry in the basement is from a lost formwork of 300 mm. external wall and internal supporting masonry of above-ground floors of clay masonry, Therm type, 300 mm. The warm flat roof is extensive, with a fall of 3%.
48

Polyfunkční dům Jihlava, Handlovy Dvory / Multifunctional House Jihlava, Handlovy Dvory

Blažek, Martin January 2019 (has links)
The subject of this diploma thesis is the project documentation of the new multifunctional building on the plot in Jihlava, Handlovy Dvory. The building is planted in the shape of a substantially elongated rhomboid and is staggered into almost half-symmetrical halves. The height of these two parts is mutually displaced by one half of the floor so that the object better copes with the significant slope of the plot. The building has five above-ground floors. On the first floor there is a beerhouse with its facilities. The beerhouse goes on to the terrace. On the second to fifth floors are individual flats. The flats are designed primarily as 1 + kitchen and 2 + kitchen. On the second floor there are also apartments. Parking is done by a perpendicular stall around the adjacent road and the car park next to the building. The work contains drawing documentation for construction, thermal engineering assessment, fire safety solution, acoustic assessment and lighting assessment
49

Muzeum automobilů / Car Museum

Suchý, Jakub January 2019 (has links)
The subject of these Master Thesis is a new building of Cars Museum. The object is located in Telc on street Radkovska, district Jihlava. This locality was chosen for its favorable conditions. In this area, there are lots of enthusiast and supporters of motorism. The nearest commission of veterans is around 50 km far. This museum is also meaning to improve a network of a commission of veterans. Telc is a beautiful historic city, which is an ideal choice for a museum of veterans. The building is divided into 3 imaginary sectors. The first one is an administrative part, which has two above-ground floors. In the first floor, there is educative room to familiarize guests with the history of vehicles, entry hall with reception, hygienic facilities for guests and base for staff and operations of the museum. In the second floor, there are offices for the museum, the commission of veterans, meeting room, storeroom, gaming-room, and daily room. The second part is the exhibition area. The third part is workshops and a base to remove operating fluids from cars. The investor is a passionate collector of historic vehicles and wants to share his collection with the public.
50

Penzion Mikulov / Boarding House Mikulov

Smolinský, Patrik January 2020 (has links)
The content of this diploma thesis is the design of a new boarding house with restaurant in Mikulov. The building has 2 above – ground floors and a partial basement. In the basement is utility room and fitness room. In 1st floor there is reception, restaurant with facilities and rooms for accomodation. One room is designed as a berrier – free. In the 2nd floor there are rooms for accomodation, facilities for cleaning and common room. The vertical supporting structures are designed from clay masonry, in the basement of the concrete formwork. The building will be covered partly by flat roof, hip roof and partly by vegetation roof. The design documentation has been prepared according to valid legal and technical regulations.

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