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1033 Uppsatser om Species composition - Sida 11 av 69

The effect of rapeseed oil and palm oil supplement and milking frequency on milk yield and milk fat quality

Milk fat is an important feature in many different milk products and other foodstuffs and it is often crucial for the dairy plants that the milk fat is stable for different manufacturing processes. Lipolysis is the enzymatic degradation of fat and is the one of the causes for an elevated amount of free fatty acids (FFA) in milk. Further, the change in fatty acid (FA) composition in milk can affect the stability of the product and also the manufacturing process. Both internal and external factors, at farm level or at the dairy plants can affect both FA composition and content of FFA. Milking frequency (MF=number of milkings per cow and day) and the composition of feed are two examples of factors generally performed at farm level. The objective of the present study was to evaluate how FA composition of milk and amount of FFA are influenced by two different ingredients supplemented to concentrate.

Hybridlärkens tillväxt i Snogeholm : hur påverkas produktionen i blandbestånd jämfört med trädslagsrena bestånd?

The hybrid larch (Larix x eurolepis Henry) is a fast growing tree species and was introduced in Sweden for about 50 years ago. The high growth and expected resistance to diseases are probably the main reasons of introducing the tree species into the Swedish forests. The purpose of this thesis was to document the production of hybrid larch planted in the Snogeholm landscape laboratory and to compare the production in the pure hybrid larch stand with the mixture together with pedunculate oak (Quercus robur). The data collection in Snogeholm since the establishment has been carried out by the Swedish University of Agricultural Science (SLU). The fieldwork for the thesis was carried out in 3 stands, containing hybrid larch, pedunculate oak and a mixture of hybrid larch and pedunculate oak, in order to be able to compare the total stand production of the areas. The results show that the total production of hybrid larch in the mixed stand only is 35 % compared with the total production of hybrid larch in the pure stand. Therefore, the hypothesis that the total production of hybrid larch is equal to the planted mixture with pedunculate oak was rejected. The other hypothesis that the total production of a 2 hectare large stand containing a mixture of hybrid larch and pedunculate oak would be greater than the total production of two pure stands of 1 hectare containing hybrid larch and oak each was also rejected. In the studied case the total production was 45 % greater if hybrid larch and pedunculate oak was planted in pure stands. The results from the case-study only indicate that the total production of hybrid larch and oak under the investigated conditions can be higher when planting the two species in pure stands compared with a mixture of the two species.

Celltal som mått på mjölkens kvalitet med avseende på mjölkens sammansättning

Mastitis, an inflammation of the udder mainly caused by a bacterial infection, induces an increase in the somatic cell count (SCC) in milk and is consequently one of several factors affecting SCC in milk. In this literature review it is investigated whether SCC; on udder quarter, cow composite or bulk tank milk level, can be used as a quality marker with focus on milk composition in terms of the content of fat, lactose, total protein, casein and whey protein. According to this literature review the relation between SCC and milk composition is not reliable either on udder quarter, cow composite or bulk tank milk level. SCC was related to lactose, casein and whey protein on udder quarter level; lactose and whey protein on cow composite level and lactose on bulk tank milk level.

Restoring biodiversity in degraded secondary rain forest in Sabah, Malaysia : natural regeneration of trees after restoration treatments

Many tropical rain forests has been lost or degraded as a result of human activities and environmental factors. Since the level of biodiversity is high in the tropics, maintaining these areas is of great importance. Forests like these are often assumed to benefit from forest restoration and rehabilitation. The INIKEA project area in Eastern Sabah, Malaysian Borneo, aims to improve biodiversity and/or species richness in the degraded forest through enrichment planting with indigenous species. The objective of this thesis was to evaluate how different treatments (liberation, gap-cluster planting and line planting) affect the biodiversity of natural regeneration in different forest types in the Rain forest Restoration Experiment, located in the INIKEA project area.

The effects of mother trees and site conditions on the distribution of natural regeneration establishment in a Bornean rainforest disturbed by logging and fire

In the tropics, logging and wild fire can result in degraded secondary forests with lower biodiversity than in the natural forest. One way to limit forest degradation is to rehabilitate the present large areas of secondary forests. However, there is a lack of knowledge concerning the ecology of tropical tree species and further studies would be advantageous for future rehabilitation efforts of degraded rainforest. The objective of this study was to investigate how mother trees in secondary forest and different site factors affect the abundance and spatial distribution of natural regeneration of non-pioneer tree species in a tropical rainforest in Sabah, Malaysia. The study took place in the INIKEA Forest Rehabilitation Project area, which suffered from wild fire in 1983 and has been selectively logged over both before and after the fire. Natural regeneration and site variables were inventoried in plots, while mother trees were inventoried in the whole survey area.

Gestaltningsfloran : en brygga mellan hortikultur och biotopgestaltning

Contemporary plant design can be examined by how it relates to two extremes - Nature and Art. This idea is explained by Noel Kingsbury in the book The Dynamic Landscape where he places designers and their projects on a gradient (Kingsbury, 2004). Nature, one of the extremes can be represented by a dynamic, species-rich plant design with native species and with nature as the ideal. The other extreme - Art implies a more static view on plant design. Here, the designs consist of colourful flowers, exotic species and cultivars with double flowers.

Insect communities inhabiting Inonotus radiatus growing on Alnus glutinosa trees at northern and southern shores of boreal lakes

This is a study of the insect community associated to the wood-decaying fungus Inonotus radiatus found on Alnus glutinosa trees growing in riparian forests at the northern and southern shores of boreal lakes in the province Uppland. Little is known about this particular bracket fungus and its inhabitants. Insects were reared out at the laboratory from samples of fruiting bodies of the fungus taken at five lakes. During the fieldwork in 2009, data about several environmental variables was also taken. After the rearing period, these variables and their effects over the insects were analyzed.

The effects of Gotland pony grazing on forest composition and structure in Lojsta hed, south eastern Sweden

Livestock animals affect their environment in a number of different ways, mostly through grazing and trampling. This study focused on the effects of Gotland pony grazing on forest structure and diversity, and the impact on ground cover. To compare the fenced and grazed area with a reference area outside the enclosure a number of transects were used. The study showed that there was no significant difference in height structure and diversity between the compared sites; however, there were a significantly higher proportion of damaged trees inside the enclosure. The ground cover variables showed a higher amount of bare soil, plant litter and wood-rush (Luzula sp.) inside the enclosure whilst grass was more frequent in the reference area.

Increased growth in Norway spruce (Picea abies (L.) Karst.) through small annual additions of nitrogen (N) fertilizer

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

Skånska trähägnader : en studie i konstruktion och historisk utbredning

The Scanian woodfences has been determined by two mainly elements: Scania's composition of tree species, with a large element of deciduous forest, and the local building tradition which has more in common with the European continent than the Swedish tradition. By examining responses from ethnological question lists deriving from the first half of the 1900s, combined with literature studies, I have been able to deepen and broaden the knowledge behind the various fencing design. In addition I ?ve constructed maps which could illustrate their historical geographic distribution.I have come to the conclusion that there was three main types of woodfences that was most common until the barbed wire was introduced in the early 1900s and later on replaced the elderly woodfences. Common for the three main types is that the base material was made out of Juniperus communis, this largely because of its durability against rot.

Interspecies embryo transfer in South American camelids : a field study

The aim of this study was to investigate the possibility of performing inter-species embryo transfer under actual field conditions in the natural habitat of South American camelids. In this study embryos from llamas were transferred to alpaca recipients. In a parallel study alpaca embryos were transferred to llama recipients. All animals used were free of uterine and ovarian abnormalities detectable by rectal palpation and /or ultrasound examination. Embryos were harvested twice after single ovulation in 10 mated female llamas and non-surgically transferred to synchronized alpaca recipients.

A literature study and survey of sycamore maple (Acer pseudoplatanus L.) in southern Sweden

Sycamore maple (Acer pseudoplatanus L.) is a common broadleaved species throughout Europe, however often of minor interest to the forest sector. There is currently a lack of research on sycamore maple, and some of its characteristics have throughout history contributed to a negative reputation in both literature and the forest society. Since broadleaved species in general are of great importance to the forest sector in Europe and presumably of enhanced significance in the future, deepened research is needed and particularly Swedish. With a desire to hopefully increase the interest for sycamore maple, was the objective of the study to examine the current status of the sycamore stands in southern Sweden. The study was carried out both as a survey with inventory field work and as a literature study. Parts of the latter mentioned is also presented in the introduction. The study shows that the majority of the sycamore stands in Sweden are growing well, producing fairly high qualities and volumes.

En ?terinventering och analys av den svenska populationen av svart nervmossa (Campylopus atrovirens)

Bristly swan-neck moss (Campylopus atrovirens) is in Sweden a very rare moss that only grows on a few blocks and cliffs around Gothenburg. The species can globally only be found in areas with high precipitation. Rain fall in Gothenburg has increased with a stronger greenhouse effect. Air pollution in Gothenburg has also improved. Mosses generally benefit from these conditions and this papers hypothesis is that the population of the species has grown because of these more beneficial conditions.

En studie av viltets påverkan på Skogssällskapets fastighet i Selesjö

This degree project investigates how elk, roe deer, red deer and fallow deer can affect an estate in Östergötland. The inventories performed within this project, were completed on an estate in Selesjö, northern Östergötland. This property is used to demonstrate wildlife management. The methods used in this study were originally developed for areas larger than individual properties. Three inventories were completed in the study. These included the recording of the number of droppings and the amount of eaten pasturage, as well as the level of damage on young trees.

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

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