No description available.

No description available.

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board. Most of the countys had a very difficult way to reach their data of the private sanitations and those who had data had great holes in their knowledge in them. The greatest emission of nitrogen was without doubt the industries, but a more even allocation could be seen in the pollution of phosphourus, where the industries and the private sanitations stood for about fifty- fifty of the pollution. The greatest emission of nitrogen and phosphourus happened in Viskan, in the drainage area for Lekvad,there it was a lack of mussels. The species of Anodonta anatina showed a strong positive correlation between emission of nitrogen and phosphourus with the way of juvenile mussels in the population. More studies is need to do in these areas, both when it comes to continuing mapping of rejuventation within the freshwater great mussels in several waters and template value for pollution of nitrogen and phosphourus, that is very doubtful today. Even studies concerning other factors, like predation, host fishes and the influence of poison and medic drugs is needing to do, as it is few studies concerning this today.

Tjädern (Tetrao urogallus) är en av arterna skogshöns med sitt utbredningsområde Europa och Ryssland. Den är väl anpassad till ett liv i det norra barrskogsbältet. Beståndet av tjäder har minskat kraftigt under efterkrigstiden över hela sitt utbredningsområde utanför Ryssland, där den dock har ökat i antal. Tack vare den ökningen anger BirdLife International beståndet som stabilt. Anledningarna till nedgången i norra delen av Europa består troligen av flera orsaker varav de förändrade skogsbruksmetoderna under andra halvan av 1900-talet kan vara en av de viktigaste. Klimatfaktorer och förändrat predationstryck kan vara andra orsaker. För att försöka se effekterna av genomförda skogsbruksåtgärder inom upptagningsområdet för tjäderns lekplatser, har 12 lekplatser i norra Skaraborg som var inventerade under 1990-1995 återinventerats under våren 2005. Antalet tuppar idag på dessa lekplatser har jämförts med tidigare situation. Ingen lekplats uppvisar någon ökning av tuppar på leken och på 5 ställen har leken övergivits helt. Arealer för de olika markslagen har uppmätts inom de 300 ha som utgör en lekplats. Analyser av korrelationen mellan de olika markanvändningarna och antalet tuppar har inte gett några signifikanta resultat (p > 0,05). Det finns en signifikant korrelation mellan förlorat antal tuppar och förändrad andel plantering (p<0,05), det har betydelse från vilken nivå förändringen sker. Anledningarna till att tupparna försvunnit på en del ställen och minskat på andra skulle kunna vara resultatet av den samlade effekten av dels skogbruksåtgärder dels övriga faktorer. Det verkar vara betydelsefullt hur stort hygget är och var det ligger i förhållande till lekcentrum om det ska påverka tjädern. Ska hänsyn kunna tas när skogsbruksåtgärder planeras är det en förutsättning att lekplatsen är känd av berörda parter. Tjäderns höga krav på sin miljö med flera olika biotoper inom reviret och dess preferens för äldre skogar med lång kontinuitet gynnar många andra arter, vilket i sin tur även gör tjädern användbar som paraplyart inom naturvården. / The capercaillie (Tetrao urogallus) is one of the species of wood fowls with distribution in Europe and Russia. It is well adapted to a life in the northern coniferous forest area. The population of capercaillies has diminished considerably during the postwar period in the whole distribution area outside Russia, where it on the contrary has increased in number. Because of this increase the BirdLife International states the population as stable. The reasons for the decrease in the northern part of Europe are believed to emanate from different sources of which the changing methods in forestry during the second half of the 20th century seem to be one of the most important ones. Climate conditions and changed predacious pressure are other possible causes. In an attempt to observe the effects of the measures in forestry taken within the distribution areas of the mating grounds of the capercailzies, twelve sites in the northern county of Skaraborg, registered during the years 1990-1995, were again registered in spring 2005. The number of male birds today on these grounds has been compared to the number of earlier registrations. No mating ground shows an increase in the number of male birds and in five places the mating ground has been totally abandoned. Within the mating ground consisting of 300 hectares the acreage of different kinds of land has been measured. The analysis of the correlation between the use of the different kinds of land and the number of male birds has not given any significant results (p> 0,05). There is one significant correlation between lost numbers of male birds and the alter of the share of plantation (p<0,05). The reason why the male birds have disappeared and in other places have diminished in number could be the result of the increased effect of both the forestry measures taken and other factors. The size of the cutting area as well as the location in relation to the centre of the mating ground seems to be of importance in influencing the capercaillie. The knowledge of the mating grounds is therefore essential to the concerned parties in planning forestry measures in a considerate way. The capercaillie has high demands upon its environment with several different biotopes within its territory; its preference for old forests with a long continuity favors several other species, which thereby makes the capercaillie useful as a general covering species in the nature conservation work.

No description available.

När storskaliga och kväveintensiva jordbruk bredde ut sig växte många betesmarker ochängar igen. Detta medförde att hävdberoende växtarter minskade eller helt försvann. Föratt kunna växa och återkolonisera marker behöver många arter olika störningar. En sådanstörning kan vara bränning. Vid bränning ökar ljusinsläppet och även kvävemängden imarken minskar, vilket gynnar de hävdberoende växterna.Detta arbete har undersökt om bränning kan vara ett komplement eller alternativ till beteoch slåtter vid bevarande av den biologiska mångfalden hos växter. I studien inventeradesbrända och orörda kontrollytor på 11 st olika gräsmarker i Östergötland. Dessagräsmarker inkluderar vägrenar, ängar, åkerslänter och naturbetesmarker.Tre olika diversitetsindex användes för att svara på om diversiteten var högre på brändamarkerna. Resultatet visade att diversiteten var högre och artfördelningen var jämnare påde brända ytorna än på kontrollytorna. De arter som är beroende av hävd hade en markantstörre utbredning på de brända markerna än på kontrollytorna. Detta bekräftar hypotesenom att bränning är positivt för hävdberoende växter och att bränning kan vara ettkomplement eller alternativ till bete och slåtter vid bevarande av den biologiskamångfalden av växter i gräsmarker. Den framtida skötseln skulle kunna vara olikakombinationer av bränningar, bete och slåtter.För naturvården kan detta konstaterande få betydelse genom att offentliga och privatamarkägare kan börja bränna fler områden med vetskapen att detta gynnar hävdberoendearter som är hotade. Att bränna marker istället för att slåttra eller beta kan leda till attstörre arealer kan få den skötsel de kräver utan förändringar i den finansiella budgetenhos markägaren. / When the large-scale and nitrogen-intensive agriculture gained land many naturalpastures and meadows started to overgrow. This led to that many species dependent onopen land decreased or totally disappeared. To grow or re-colonize land many speciesneed some form of disturbance. Burning can be one of such disturbances. Burningincrease the light inlet and decrease the amount of nitrogen in the soil. Both of thesechanges will favor the open-land species.The aim of this study was to explore if burning could be a complement or alternative tograzing and mowing for preserving the biological diversity among plants in grasslands.The different kinds of grasslands that were inventoried include hard shoulders, meadows,field slopes and natural pastures. Both burned and control areas were inventoried at 11places. All of them were located in different habitats in Östergötland, Sweden.Three different diversity-indexes have been used to answer the question if diversity washigher on the burned areas than on the control surface. The result showed that both thediversity was higher and the distribution in species spread more evenly on the burnedareas. Species dependent on open land had a notably larger spreading on the burned areasthan on the control areas. This confirms the hypothesis that burning has a positive effecton open-land species and can be a complement or replacement for grazing or mowing inpreserving the biological diversity of plants in grasslands. The future care could bedifferent combinations of burning, grazing and mowing.To the conservation, this knowledge can have a great impact for both state and privatelandowners. Knowing that this method will favor the open-land species, more areas canbe burned. To burn, instead of mowing or grazing, can lead to that larger areas can havethe proper maintenance it requires, without changes in the financial budget of thelandowner.

The interaction between terrestrial ecosystems and the atmosphere continues to be a central research theme within climate, hydrology, and ecology communities. This interest is stimulated by research issues pertinent to both the fundamental laws and the hierarchy of scales. To further explorer such topics over various spatial and temporal domains, in this study, biosphere-atmosphere interactions are studied at two different scales, leaf-to-canopy and canopy-to-atmospheric boundary-layer (ABL) scales, by utilizing both models and long-term measurements collected from the Duke Forest AmeriFlux sites. For the leaf-to-canopy scale, two classical problems motivated by contemporary applications are considered: (1) ‘inverse problem’ – determination of nighttime ecosystem respiration, and (2) forward problem – estimation of two-way interactions between leaves and their microclimate ‘’. An Eulerian inverse approach was developed to separate aboveground respiration from forest floor efflux using mean CO2 concentration and air temperature profiles within the canopy using detailed turbulent transport theories. The forward approach started with the assumption that canopy physiological, drag, and radiative properties are known. The complexity in the turbulent transport model needed for resolving the two-way interactions was then explored. This analysis considered a detailed multi-layer ecophysiological and radiative model embedded in a hierarchy of Eulerian turbulent closure schemes ranging from well-mixed assumption to third order closure schemes with local thermal-stratification within the canopy. For the canopy-to-ABL scale, this study mainly explored problems pertinent to the impact of the ecophysiological controls on the regional environment. First, the possible combinations of water states (soil moisture and atmospheric humidity) that trigger convective rainfall were investigated, and a distinct ‘envelope’ of these combinations emerged from the measurements. Second, an analytical model as a function of atmospheric and ecophysiological properties was proposed to examine how the potential to trigger convective rainfall shifts over different land-covers. The results suggest that pine plantation, whose area is projected to dramatically increase in the Southeastern US (SE), has greater potential to trigger convective rainfall than the other two ecosystems. Finally, the interplay between ecophysiological and radiative attributes on surface temperature, in the context of regional cooling/warming, was investigated for projected land-use changes in the SE region. / Dissertation

The Uncompahgre River in Ouray, CO, was modified in 1996 from a braided river system to a meandering river channel. Large boulders of riprap were placed along designed meanders to prevent erosion and enable the development of permanent human structures on the flood plain. Deposition of gravel bars in the modified channel occurs annually during the summer. This gravel is "mined" by the City of Ouray; however, the effects of this excavation and the original modification were never assessed. This study provides an assessment by quantifying cross-sectional area change, cumulative grain-size distributions, shear stresses, slopes, and sinuosities using traditional survey methods. In addition, volume change of a gravel bar inside the modified channel was estimated using extreme oblique photographs (>45 degrees from nadir) that were obtained from nearby cliffs. Close-range photogrammetry was used in the natural channel downstream to evaluate photogrammetric methods using different lenses, image sensors, and camera geometries. Both traditional and photogrammetric methods clearly indicated significant deposition in the modified channel, whereas erosion occurred directly downstream from the modified channel, but did not occur at a reach 1.5 km downstream. In the natural channel, no cross-sectional area change occurred, grains were poorly sorted, and the longitudinal slope was ~four times steeper than the modified channel. Shear stress ratios were used as an erosion threshold, which did not correlate with actual cross-sectional area change, but a decrease in shear stress ratios from May 2011 to September 2011 were associated with erosion. Average RMSE values for DEMs created from extremeoblique photographs of a gravel bar in May 2011 and September 2011 were 0.140 m and 0.324 m, respectively. Using a DEM of difference with a t-statistic filter revealed that 115m3 of gravel was deposited. The Uncompahgre River showed similar geomorphic characteristics to other rivers in southwest Colorado, however, the slope of the natural and modified channels were much steeper than other rivers. Extreme-oblique photography and unconventional sensors both yielded reliable results, showing that these atypical techniques can be used in terrestrial photogrammetric applications such as, post-restoration assessments, as long as proper base-to-height ratios are achieved.

<p>När storskaliga och kväveintensiva jordbruk bredde ut sig växte många betesmarker ochängar igen. Detta medförde att hävdberoende växtarter minskade eller helt försvann. Föratt kunna växa och återkolonisera marker behöver många arter olika störningar. En sådanstörning kan vara bränning. Vid bränning ökar ljusinsläppet och även kvävemängden imarken minskar, vilket gynnar de hävdberoende växterna.Detta arbete har undersökt om bränning kan vara ett komplement eller alternativ till beteoch slåtter vid bevarande av den biologiska mångfalden hos växter. I studien inventeradesbrända och orörda kontrollytor på 11 st olika gräsmarker i Östergötland. Dessagräsmarker inkluderar vägrenar, ängar, åkerslänter och naturbetesmarker.Tre olika diversitetsindex användes för att svara på om diversiteten var högre på brändamarkerna. Resultatet visade att diversiteten var högre och artfördelningen var jämnare påde brända ytorna än på kontrollytorna. De arter som är beroende av hävd hade en markantstörre utbredning på de brända markerna än på kontrollytorna. Detta bekräftar hypotesenom att bränning är positivt för hävdberoende växter och att bränning kan vara ettkomplement eller alternativ till bete och slåtter vid bevarande av den biologiskamångfalden av växter i gräsmarker. Den framtida skötseln skulle kunna vara olikakombinationer av bränningar, bete och slåtter.För naturvården kan detta konstaterande få betydelse genom att offentliga och privatamarkägare kan börja bränna fler områden med vetskapen att detta gynnar hävdberoendearter som är hotade. Att bränna marker istället för att slåttra eller beta kan leda till attstörre arealer kan få den skötsel de kräver utan förändringar i den finansiella budgetenhos markägaren.</p> / <p>When the large-scale and nitrogen-intensive agriculture gained land many naturalpastures and meadows started to overgrow. This led to that many species dependent onopen land decreased or totally disappeared. To grow or re-colonize land many speciesneed some form of disturbance. Burning can be one of such disturbances. Burningincrease the light inlet and decrease the amount of nitrogen in the soil. Both of thesechanges will favor the open-land species.The aim of this study was to explore if burning could be a complement or alternative tograzing and mowing for preserving the biological diversity among plants in grasslands.The different kinds of grasslands that were inventoried include hard shoulders, meadows,field slopes and natural pastures. Both burned and control areas were inventoried at 11places. All of them were located in different habitats in Östergötland, Sweden.Three different diversity-indexes have been used to answer the question if diversity washigher on the burned areas than on the control surface. The result showed that both thediversity was higher and the distribution in species spread more evenly on the burnedareas. Species dependent on open land had a notably larger spreading on the burned areasthan on the control areas. This confirms the hypothesis that burning has a positive effecton open-land species and can be a complement or replacement for grazing or mowing inpreserving the biological diversity of plants in grasslands. The future care could bedifferent combinations of burning, grazing and mowing.To the conservation, this knowledge can have a great impact for both state and privatelandowners. Knowing that this method will favor the open-land species, more areas canbe burned. To burn, instead of mowing or grazing, can lead to that larger areas can havethe proper maintenance it requires, without changes in the financial budget of thelandowner.</p>

<p>This thesis has two aims. The first one is the investigation and analysis of the errors occurring in the measurements with pulsed time-of-flight (TOF) terrestrial laser scanners (TLS). A good understanding of the error sources and the relationships between them is necessary to secure the data accuracy. We subdivide these errors into four groups: instrumental, object-related, environmental and methodological. Based on our studies and the results obtained by other researchers, we have compiled an error model for TLS, which is used to estimate the single-point coordinate accuracy of a point in the point cloud, transformed to the specified coordinate system.</p><p>The second aim is to investigate systematic instrumental errors and performance of three pulsed TOF laser scanners – Callidus 1.1, Leica HDS 3000 and Leica HDS 2500 – and to develop calibration procedures that can be applied by the users to determine and correct the systematic errors in these instruments. The investigations have been performed at the indoor 3D calibration field established at KTH and outdoors. The systematic instrumental errors, or calibration parameters, have been estimated in a self-calibration according to the parametric least-squares adjustment in MATLAB®. The initial assumption was that the scanner instrumental errors are similar to those in a total station. The results have shown that the total station error model is applicable for TLS as a first approximation, but additional errors, specific to the scanner design, may appear. For example, we revealed a significant vertical scale error in the scanner Callidus 1.1, caused by the faults of the angular position sensor. The coordinate precision and accuracy of the scanners, estimated during the self-calibration, is at the level of several millimetres for Callidus 1.1 and Leica HDS 3000, and at the submillimetre level for Leica HDS 2500.</p><p>In other investigations, we revealed a range drift of up to 3 mm during the first few hours of scanning, presumably due to the changes in the temperature inside the scanners. The angular precision depends on the scanner design (“panoramic” or “camera-like”), and the angular accuracy depends on the significant calibration parameters in the scanner. Investigations of the influence of surface reflectance on the range measurements have shown that the indoor illumination and surface wetness have no tangible influence on the results. The type of the material does not affect, in general, the ranging precision for Callidus 1.1, but it affects the ranging precision and accuracy of the scanners Leica HDS 3000 and Leica HDS 2500. The reason may be different wavelength and, possibly, different design of the electronics in the laser rangefinders. Materials with high reflectance and those painted with bright “warning” colours may introduce significant offsets into the measured ranges (5 – 15 cm), when scanned from close ranges at normal incidence with the scanner Leica HDS 3000. “Mixed pixels” at the object edge may introduce a range error of several centimetres, on the average, depending on the type of the material. This phenomenon leads also to the distortions of the object size, which may be reduced by the removal of the “mixed pixels” based on their intensity. The laser beam intensity recorded by the scanner tends to decrease with an increased incidence angle, although not as assumed by the popular Lambertian reflectance model. Investigations of the scanner Leica HDS 2500 outdoors have revealed no significant influence of the “normal” atmospheric conditions on the range measurements at the ranges of up to 50 m.</p><p>Finally, we have developed and tested two simple procedures for the calibration of the vertical scale (and vertical index) error and zero error in laser scanners. We have also proposed an approach for the evaluation of the coordinate precision and accuracy in TLS based on the experiences from airborne laser scanning (ALS).</p>