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719 Uppsatser om Invasive alien species - Sida 28 av 48
Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites
The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value.
Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.
Vegetationsutveckling och mänsklig aktivitet under äldre Stenålder vid Döudden, Arjeplog kommun :
The landscape in the interior of Norrland has undergone dramatic changes since the deglaciation as a consequence of faultings, earthquakes and tilting of the landscape westwards. Archaeological investigations along former shorelines by the use of models of isostatic land uplift, have revealed many Mesolitic settlements in northern Sweden. Döudden, in the county of Arjeplog, has been investigated by archaeologists that identified settlements from 5200 BC. The objective of this study was to analyse the history of the vegetation and if the vegetation showed traces of human activity during early Holocene, by pollen analysis. The results indicate that the area had an established vegetation c.
Näsnarens framtid i ett näringsstatusperspektiv
Eutrophication has been a problem in aquatic systems for a long time. It is well known that the key nutrient to control the eutrophication process is phosphorus. Lately, it has been possible to reverse the process and recover lakes from eutrophication.During a long time Lake Näsnaren in Katrineholms kommun, Södermanland, has been exposed of a large amount of phosphorus from the city's wastewater. The lake has a great value as a habitat of rare species but also a high recreation value for people living in Katrineholm and Södermanland. Lake Näsnaren is situated in a Natura 2000 area.
Hundägares och kattägares relation till sitt djur :
The relationship between the pet and it's owner is a very important and interesting
issue. Unfortunately there is not so much research on this and in addition to that
Swedish veterinarian education does not put much emphasis on pet's role in society
or their pattern of behaviour nor treatment. This thesis is based on an opinion poll
that 20 dog owners and 20 cat owners contributed. The main purpose of the thesis
was to compare the relationships that the pet (dog or cat) and its owner can have.
The issues such as the pet owner's attitude to his/her pet, how the pet owner
percieves and interprets the signals from the animal, and what they think about the
natural behaviours and needs that their pets (might) have.
The results show that dog- and cat owners are people who generally love animals,
that they used to have even other animal species in the past, but when it comes to
choice between a new dog or a new cat they choose the one that they previously
have had and that they are used to. Most of a dog owners choose the dog to be their
pet because of the company while the majority of a cat owners choose cat because
cats are independent and they are used to cats.
Lugnare katter på kliniken? : en studie om användningen av syntetiska analoger tillfelina ansiktsferomoner på svenska djursjukhus
Pheromones are chemical substances representing very specific signal messages within a species. Although a lot remains unknown about their precise effects, it is known that pheromones influence the behaviour of the receiver. Since the mid 1990s, when it was first possible to synthesise analogues of two fractions of feline facial pheromone, F3 (Feliway®) and F4 (Felifriend®), these have been used in so called pheromonotherapy to treat behavioural problems in cats. The initial use of pheromones for specific behavioural problems has been extended to cover the wide field of stress related issues. This studycontains a questionnaire where veterinary nurses and surgeons at 50 Swedish veterinary hospitals and clinics were asked about their use of synthetic analogues to feline facial pheromones in the care and treatment of cats.
Utvärtes behandling av sarkoider på häst med Aldara TM eller Xxterra TM : en jämförande pilotstudie
Sarcoid is the most common tumor in horses all over the world. The sarcoid is a benign, locally invasive, usually fibroblastic proliferative skin neoplasm. Even if the etiology is not completley verified, the epidemiology and clinical behavior suggest a infectious intervention, probably BPV type 1 or type 2. However, it is known that the cause is multifactorial. A genetic prepdispositon has been identified associated to genes within the Major Histocompatibility Complex (MHC), but also to breed, age and perhaps gender.
Utvärtes behandling av sarkoider på häst med Aldara eller Xxterra : en jämförande pilotstudie
Sarcoid is the most common tumor in horses all over the world. The sarcoid is a benign, locally invasive, usually fibroblastic proliferative skin neoplasm. Even if the etiology is not completley verified, the epidemiology and clinical behavior suggest a infectious intervention, probably BPV type 1 or type 2. However, it is known that the cause is multifactorial. A genetic prepdispositon has been identified associated to genes within the Major Histocompatibility Complex (MHC), but also to breed, age and perhaps gender.
Tame animals in the wilderness : livestock grazing around summer farms in Jämtland, boreal Sweden 1800-2011
The forest and mire landscape surrounding the north Swedish villages have been of fundamental importance through time for the farmers. In the Scandinavian summer farm system the forest and mire pasture was used to its full potential. The system consisted of smaller summer farms some kilometres from the main farm in the village, and were the livestock grazed in the forest around the summer farm. The livestock affect their environment, and grazed forests generally contain a higher biodiversity than an ungrazed forest. The overall aim of this thesis is to understand the impact of livestock grazing on a northern forest ecosystem over a long time period.
Mjölkraskvigors tillväxt på naturbete :
To turn the dairy heifers out on pasture is the most natural way for the cattle to get feed.
At the same time it is cheap and if it is right treated a feed of high nutritive value. The
problem today is to get dairy heifers to grow enough when they are grazing at natural
pasture for the entire summer. Therefore, the opinions differ whether pasture is a
resource or a problem.
The increasing interest of pasture production is due to the fact that you can receive
grants for preserving valuable natural assets and cultural landscape elements in the
pasture land.
A high grazing pressure is necessary to preserve an open landscape and a great variety
of species. In the same time the heifers have to supply their nutritive needs in order to
grow and be large enough to show heat and be pregnant in right time to calve with a
sufficient body size and at an economically right age.
This paper includes a literature review on natural pasture, pasture production, and
growth of dairy heifers together with own interviews with dairy farmers about their
point of view to the pasture husbandry on the farms, how they plan for pasture, look
after natural pasture, treatment areas and take care of the calves and heifers. The results
indicate that the time it takes and the demanded work are the biggest factors to how and
why the farmers do as they do..
Närsalter och bottenlevande organismer i Mönsteråsviken
The focus of this study was to examine the nutrients and benthic organisms of the bay ?Mönsteråsviken?, which is influenced by eutrophication. The purpose was also to look at an interesting gradient forming in the bay, namely the distance from the river outflow of Lillån. At 18 sampling sites in the bay samples of water, sediments and benthic organisms were collected in late April of 2011. The water was analyzed for nitrate, phosphate and chlorophyll.
Mårdhunden ? ett hot mot europeiska ekosystem?
Mårdhunden är en invasiv art i Europa och har tack vare sin generalistiska diet, hög reproduktivitet och stor anpassningsbarhet lyckats etablera sig i stora delar av Nord-, Öst- och Centraleuropa. Den introducerades i tidigare västra Sovjetunionen mellan 1929 och 1955 med syftet att få ett nytt pälsdjur att jaga. Då mårdhunden gärna vandrar långa sträckor spred den sig snart från utsättningsområdena och etablerades i Europa. I dagsläget finns det en oro för att den ska påverka andra arter och deras ekosystem samt att den ska sprida olika parasit- och virussjukdomar. Min studie undersöker om man sett någon påverkan på andra arter och huruvida mårdhunden fungerar som sjukdomsspridare.
Hur ska tall- och gran bestånd i Götaland gallras för att minska risken för vindskador?
With knowledge of how the southern Swedish forests have been affected by storms the past years, this study intended to find out which factors affect the storm firmness of a stand the most. The study was based on data from stands in the, by the storm Gudrun, affected area. The results of the analyses that tested the stand factors that influence the amount of storm damage to the greatest extent showed that the storm sensitivity of Norway spruce stands were largely due to previous management actions. The factors that could be controlled by thinning and had relevance of storm damage standpoint, according to the results were; the dominant height, volume, basal area weighted mean diameter and stand age at last thinning. In this study, these results are not as clear for Scots pine.
Djurskyddsinspektörer : - Behovet av kunskap om exotiska djur
Psittacines and reptiles are exotic animals that are difficult to care for and it requires extra knowledge to make a correct assessment of their wellbeing. An animal welfare inspector, with an education in general animal welfare, may not have a deep enough knowledge of exotic animals to do a proper assessment of the animal?s general condition and its environment. In this paper it was therefore examined if animal welfare inspectors have enough knowledge to do a satisfying inspection of establishments working with selling of exotic animals. A literature study was used to examine difficulties with each species.
Fälttest av en ny metod att med objektiva mätmetoder karaktärisera egenskaperna hos ridunderlag- en pilotstudie. :
Background
Research concerning footing and its contribution to injuries has been conducted primarily in racing Thoroughbreds. Studies in UK and Japan indicate that some specific factors could be responsible for an increase in performance-associated injuries. Researchers in Sweden have performed studies on Standardbred trotters. More research is needed to be done on equestrian sports since requirements on footing are not exactly the same in riding and trotting horses.
The lack of scientific evidence on the construction of equestrian surfaces has lead to anecdotal validation of designs.
Skogsskötsel för att främja sociala och estetiska värden i ett friluftsområde i Trollhättans Stad
Over 80% of Sweden's population lives in urban areas, and half of the country's forest visits will thus be in urban woodlands. Social values ??- how the individual experiences the forest, and the impact of the forest visits on individual health and well-being, are pointing to the importance of managing the urban woodlands.When there comes to the cultivation of the urban woodlands there are usually many opinions to consider.This study aims to investigate the various opinions on the use and forestry in an urban recreation area in ??the City of Trollhättan. The study addresses both general and in four cases specific suggestions on management methods.Data was obtained from both quantitative and qualitative study through survey, interviews and discussions with the users of the recreation area.Trollhättan's goal with the recreation area is to make it accessible to local residents. The users are mainly influenced by the accessibility therefore clearings and thinnings are appreciated.