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159 Uppsatser om Stormwater harvesting - Sida 2 av 11

Gödslingsstrategins inverkan på Holmen Skog, Umeå distrikt

This thesis analyzes the effects of different fertilization strategies on forest management at Holmen Skog in Umeå district. Harvesting volumes, net present values and fertilization intensity are presented for each fertilization scenario. The planning reserve (percentage area older than minimum final felling age) was also analyzed in this study.The thesis covers the analysis of five different fertilization scenarios, varying in fertilization intensity, from no fertilization at all, to fertilization at every harvesting operation (thinning or final felling). A sub-study was also carried out so the reader in detail can see how the different fertilization scenarios affect individual forest stands of different nature. The analysis has been done with the planning tool PlanWise, which is an application of the Heureka analysis and planning system.

Exercise pens as an environmental enrichment for laboratory rabbits

This thesis analyzes the effects of different fertilization strategies on forest management at Holmen Skog in Umeå district. Harvesting volumes, net present values and fertilization intensity are presented for each fertilization scenario. The planning reserve (percentage area older than minimum final felling age) was also analyzed in this study.The thesis covers the analysis of five different fertilization scenarios, varying in fertilization intensity, from no fertilization at all, to fertilization at every harvesting operation (thinning or final felling). A sub-study was also carried out so the reader in detail can see how the different fertilization scenarios affect individual forest stands of different nature. The analysis has been done with the planning tool PlanWise, which is an application of the Heureka analysis and planning system.

Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter

This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The nutrients will then be recirculated to arable land through residues from biogas production. The amount of nutrients that can be removed by harvesting the biomass depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts. Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance. This literature has illuminated a major environmental problem and it has been suggested optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a definite answer for the optimal method for each site tests should be carried out, this because many factors determine to what is suitable for each, specific environment. .

Dagvatten i Märsta : förslag till anläggning för ekologisk hantering samt metodöversikt

Stormwater in urban areas has been treated as a problem for a long time. The large proportion of impermeable surfaces inhibits the water from infiltrating in the ground to the same extent that it does in nature. This causes intensive surface flow during rain, which in turn causes inconveniences such as decreased accessability, floods and increased risk of desease spreading. Drainage through pipes is the traditional and usually functional metod for storm water disposal. That is as long as water flows are moderate. But precipitation varies naturally in amount and intensity and additional impermeable surfaces make some pipes insufficient for heavy or lasting precipitation.

Bestämning av dagvattenflöden i Knivstaåns avrinningsområde

The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.

Göteborgs blå struktur : med studie av Osbäcken

Gothenburg municipality has a lot of natural water. This paper enhances the function and importance of water in the city. It also deals with the problems of sewage water and flooding. Gothenburg has reached an advanced stage of water planning. By developing a Waterplan, the municipality highlight that water has an important position in the urban planning.

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

Gröna tak som del i ett hållbart stadsbyggande

Green roofs have seen a revival in the society of today. They provide many functions of which both society as a whole and the individual can take part. In particular extensive green roofs, that requires little or even zero maintenance, provides very valuable functions. Green roofs affect our environment and our economy in a positive manner as well as the physical expression of buildings. In this bachelor thesis the impact of green roofs on society has been examined throughout literature studies. The result as a compilation of contemporary research in this field is presented together with a discussion about the use of green roofs in general. The two major arguments for an extended use of green roofs are, the high stormwater retention capacity and the cost-benefits seen over time compared to a conventional roof.

Analys av framtida potential för virkesköp från privata skogsägare i Västerbottens län : beslutsunderlag för virkesköpsstrategier

This study was conducted on behalf of SCA forest AB, Västerbottens forest administration. Timber procurement from non-industrial private forest owners has become an increasingly important part of SCA:s wood supply. The objectives of this study was to report the current forest conditions in the private forests in the county of Västerbotten, analyse the potential for procurement of wood from private forest owners, and provide a basis for decisions on future strategies for timber procurement from private owners.Material and data have been collected from different sources, mainly from Swedish National Forest Inventory and SKA-VB08. This material was the basis for the analysis and calculations performed with the Heureka application PlanWise. This study area was divided into six different analytical areas (Coastal south, Coastal middle, Lycksele, Inland south, Inland north, Skellefteå), where each area of analysis is represented by a number of municipalities.In this study, two scenarios were specified; one describing the current forest management with current harvesting levels and the effects of these assumptions, the second to illuminate what potential there is for future timber harvesting.

Vilken är den teoretiskt optimala toppdiametern på bokmassaved vid motormanuell avverkning?

The bioenergy market has been introduced relatively late in a perspective of the Swedish forestry. Nowadays branches and tops are used more frequently as bioenergy after harvesting. Therefore, it has developed a competitive situation between pulpwood and bioenergy. This situation has even established some questions. Two examples of these are: ? At what top diameter should the final piece of pulpwood be crosscut to get the best economically result? ? Should the top diameter, at the final piece of pulpwood, be crosscut at a thicker or smaller diameter than what is done today? The purpose of this report is to answer these two questions when the harvesting is made motor manually in beech stands.

Jämförande tidsstudie vid riskörning med kompakteringsskotare och traditionell ?lätt? modifierad skotare :

This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The work was an assignment from Sydved Energy AB. The aim of the work was to compare the operational productivity between two kinds of forwarders for extraction of harvesting residues, one forwarder with a special compression device and one ordinary, slightly modified forwarder. Two sites were studied for each forwarder. The study shows that the annual production was about 11,000 m3 higher for the traditional forwarder. The cost for the traditional forwarder was SEK 0.9 lower per m3.

Biomassauttag vid delkvistat sortiment i klen gallring

The purpose of this study was to estimate the removal of biomass in connection with thinning operations in young stands that are dominated by small diameter trees. The economy of such operations depends on the products generated as well as the performance of the harvesting systems. Conversion tables designed to predict the outcome based on harvesting method was another goal of this study. Removal of biomass affects the nutrient composition of the site. Therefore it is a purpose that this study will provide researchers with some variables that can be utilized when studying this aspect. Trees were harvested and divided into bunches based on diameter.

Analys av mjuka faktorer som påverkar grotuttaget från hygge till avlägg inom Sveaskogs organisation

Biofuels are getting more important as EU plans to replace fossil fuels with renewable energy sources. Because of that Sveaskog has chosen to invest in developing the handling process of logging residue. The company has a joined organisation for handling both round wood and logging residue. They are also working at integrating the forwarding of the logging residue with the rest of the harvesting team. Sveaskog is currently extracting 44 % of the available amount of logging residue.

Utvärdering av en subjektiv metod för att skatta mängden trädbiomassa längs vägkanter :

Forest biomass is becoming an increasingly important source of renewable energy, and thereby the demand is increasing. There is currently 213 000 km of forest roads in Sweden that could be suitable for biomass harvesting. Harvest of biomass along forest roads both provides biomass and maintains the quality of the roads. Currently, the volume of biomass along roads can only be assessed post harvest, chipping and industry deliverance. As the decision of whether or not to harvest should preferably be based on more than experience, the TJ-method has been proposed. The TJ-method is a subjective method to quickly determine the dry matter quantity with the assessment being conducted from the roadside.

Planering av vägupprustning med hjälp av GIS och optimering : en fallstudie på Holmen Skog

The objective of this thesis was to develop a method for the planning of road upgrading at Holmen Skog, a Swedish forest company. A critical issue for creating such plans is to identify roads that are suitable to upgrade to a standard that can handle heavy traffic during spring thaw, since spring thaw is a bottle neck for transporting timber. The method was tested in a case study at a district. The work consisted of two parts. The first was to retrieve and prepare geographical data for the roads.

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