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61.
Timo Pukkala 《林业研究》2019,(5):1581-1593
Raster type of forest inventory data with site and growing stock variables interpreted for small squareshaped grid cells are increasingly available for forest planning.In Finland,there are two sources of this type of lattice data:the multisource national forest inventory and the inventory that is based on airborne laser scanning(ALS).In both cases,stand variables are interpreted for 16 m×16 m cells.Both data sources cover all private forests of Finland and are freely available for forest planning.This study analyzed different ways to use the ALS raster data in forest planning.The analyses were conducted for a grid of 375×375 cells(140,625 cells,of which 97,893 were productive forest).The basic alternatives were to use the cells as calculation units throughout the planning process,or aggregate the cells into segments before planning calculations.The use of cells made it necessary to use spatial optimization to aggregate cuttings and other treatments into blocks that were large enough for the practical implementation of the plan.In addition,allowing premature cuttings in a part of the cells was a prerequisite for compact treatment areas.The use of segments led to 5–9%higher growth predictions than calculations based on cells.In addition,the areas of the most common fertility classes were overestimated and the areas of rare site classes were underestimated when segments were used.The shape of the treatment blocks was more irregular in cell-based planning.Using cells as calculation units instead of segments led to 20 times longer computing time of the whole planning process than the use of segments when the number of grid cells was approximately 100,000. 相似文献
62.
Samuli Launiainen Gabriel G. KatulPasi Kolari Timo VesalaPertti Hari 《Agricultural and Forest Meteorology》2011,151(12):1672-1689
Linkage between the leaf-level stomatal conductance (gs) response to environmental stimuli and canopy-level mass exchange processes remains an important research problem to be confronted. How various formulations of gs influence canopy-scale mean scalar concentration and flux profiles of CO2 and H2O within the canopy and how to derive ‘effective’ properties of a ‘big-leaf’ that represents the eco-system mass exchange rates starting from leaf-level parameters were explored. Four widely used formulations for leaf-level gs were combined with a leaf-level photosynthetic demand function, a layer-resolving light attenuation model, and a turbulent closure scheme for scalar fluxes within the canopy air space. The four gs models were the widely used semi-empirical Ball-Berry approach, and its modification, and two solutions to the stomatal optimization theory for autonomous leaves. One of the two solutions to the optimization theory is based on a linearized CO2-demand function while the other does not invoke such simplification. The four stomatal control models were then parameterized against the same shoot-scale gas exchange data collected in a Scots pine forest located at the SMEAR II-station in Hyytiälä, Southern Finland. The predicted CO2 (Fc) and H2O fluxes (Fe) and mean concentration profiles were compared against multi-level eddy-covariance measurements and mean scalar concentration data within and above the canopy. It was shown that Fc comparisons agreed to within 10% and Fe comparisons to within 25%. The optimality approach derived from a linearized photosynthetic demand function predicted the largest CO2 uptake and transpiration rates when compared to eddy-covariance measurements and the other three models. Moreover, within each gs model, the CO2 fluxes were insensitive to gs model parameter variability whereas the transpiration rate estimates were notably more affected. Vertical integration of the layer-averaged results as derived from each gs model was carried out. The sensitivities of the up-scaled bulk canopy conductances were compared against the eddy-covariance derived canopy conductance counterpart. It was shown that canopy level gs appear more sensitive to vapor-pressure deficit than shoot-level gs. 相似文献
63.
Gerhard Strauch Monika Möder Rainer Wennrich Karsten Osenbrück Hans-Reinhard Gläser Timo Schladitz Claudia Müller Kristin Schirmer Frido Reinstorf Mario Schirmer 《Journal of Soils and Sediments》2008,8(1):23-33
Background, Aim and Scope Our study focuses on the indication of anthropogenic impacts on the urban surface and groundwater in large cities, demonstrated
for the cities of Halle/Saale and Leipzig (Germany). For the study we selected indicator substances such as xenobiotics, trace
elements, and stable isotopes which are connected to human activities in urban areas. The xenobiotics reported here are the
pharmaceutical carbamacepine, the polycylic musk compounds galaxolide and tonalide, the life style product caffeine, and industrial
chemicals such as bisphenol A and t-nonylphenol. The investigated xenobiotics pose largely unknown risks to human health and
the aquatic ecosystem. Trace elements are represented by the rare earth element gadolinium (Gd), used as magnetic resonance
imaging contrast substance. Nitrogen isotopes in dissolved nitrate characterize the origin of nitrogen compounds, mixing and
reaction processes.
Methodology River water was sampled along the flow path of the rivers Saale and Weisse Elster through the city of Halle/Saale, the rivers
Luppe and Weisse Elster through the city of Leipzig. Separate samples were collected from the effluent of the local waste
water treatment plants. Groundwater from Quaternary plain aquifers along the rivers and from different urban locations was
collected at the same time. The indicators were analysed and assessed according to their sources, concentration and distribution
patterns.
Results and Discussion Based on the nitrogen isotopic signature, dissolved nitrate in river water of the Saale was referred mainly to two sources:
the effluent of the water treatment plant and a mixture of diffusive inputs from rain water channels, sewage leakages and
agriculture activities along the rivers. The Gd anomaly was recognized in surface water of both cities, particularly in the
effluent of the water treatment plants, but clearly attenuated in groundwater. We measured concentrations of xenobiotics in
river and sewer water between 10 and 60,000 ng L−1, and, in groundwater, one order of magnitude lower. Distinctions of xenobiotic patterns were found in river water before
and after the effluent of treated waste water into the rivers. Degradation of endocrine disrupters and fragrances, but also
persistence of carbamacepine were recognized as essential processes during waste water treatment. At the study site Halle/Saale,
mass balances were set up for xenobiotics and water fluxes.
Conclusions At both sites, we demonstrated that indicators such as xenobiotics, gadolinium, and nitrogen isotopes are suitable for assessing
anthropogenic impacts on urban water. However, the behaviour of these indicators in surface and groundwater has to be considered
according to the different geochemical environments. 相似文献
64.
65.
Prevalence of antibodies against feline panleukopenia virus in client-owned cats in Southern Germany
Katherina Mende Bianca Stuetzer Carola Sauter-Louis Timo Homeier Uwe Truyen Katrin Hartmann 《Veterinary journal (London, England : 1997)》2014,199(3):419-423
Feline panleukopenia is a frequent and commonly fatal disease of cats. Recent published studies have raised suspicions that some cats fail to develop antibodies after vaccination. The purpose of this study was to assess the prevalence of antibodies against feline panleukopenia virus (FPV) in cats in Southern Germany, and to identify factors that are associated with a lack of antibodies. In total, 350 cats presented to the Clinic of Small Animal Medicine, Ludwig-Maximilians-Universitaet were randomly included in the study. Information regarding signalment, origin, environment, lifestyle, housing conditions, health status, chronic diseases, glucocorticoid therapy, and vaccination status were collected. Antibodies were detected by haemagglutination inhibition test. Asymptomatic chi-squared tests and univariable logistic regression were used to investigate associations between a lack of antibodies and the different variables. Associations determined to be statistically significant at P < 0.1 were verified by a multivariable logistic regression analysis.Of the 350 cats, 103 (29.4%) had no antibodies against FPV. Chronic kidney disease, neoplasia, glucocorticoid therapy, and vaccination status were significantly associated with a lack of antibodies. The cats with no antibodies were likely to have inadequate immunity against panleukopenia and those with chronic diseases or receiving glucocorticoids were less likely to be protected. 相似文献
66.
Michael Preisitsch Stefan E. Heiden Monika Beerbaum Timo H. J. Niedermeyer Marie Schneefeld Jennifer Herrmann Jana Kumpfmüller Andrea Thürmer Inga Neidhardt Christoph Wiesner Rolf Daniel Rolf Müller Franz-Christoph Bange Peter Schmieder Thomas Schweder Sabine Mundt 《Marine drugs》2016,14(1)
In this study, the influence of halide ions on [7.7]paracyclophane biosynthesis in the cyanobacterium Nostoc sp. CAVN2 was investigated. In contrast to KI and KF, supplementation of the culture medium with KCl or KBr resulted not only in an increase of growth but also in an up-regulation of carbamidocyclophane production. LC-MS analysis indicated the presence of chlorinated, brominated, but also non-halogenated derivatives. In addition to 22 known cylindrocyclophanes and carbamidocyclophanes, 27 putative congeners have been detected. Nine compounds, carbamidocyclophanes M−U, were isolated, and their structural elucidation by 1D and 2D NMR experiments in combination with HRMS and ECD analysis revealed that they are brominated analogues of chlorinated carbamidocyclophanes. Quantification of the carbamidocyclophanes showed that chloride is the preferably utilized halide, but incorporation is reduced in the presence of bromide. Evaluation of the antibacterial activity of 30 [7.7]paracyclophanes and related derivatives against selected pathogenic Gram-positive and Gram-negative bacteria exhibited remarkable effects especially against methicillin- and vancomycin-resistant staphylococci and Mycobacterium tuberculosis. For deeper insights into the mechanisms of biosynthesis, the carbamidocyclophane biosynthetic gene cluster in Nostoc sp. CAVN2 was studied. The gene putatively coding for the carbamoyltransferase has been identified. Based on bioinformatic analyses, a possible biosynthetic assembly is discussed. 相似文献
67.
68.
Field experiments with mixtures of barley and oats in southern Finland demonstrated a reduction in barley scald disease caused by Rhynchosporium secalis on upper leaves compared with that on pure barley stands. Mixtures lowered disease-induced yield reductions only slightly. In general, barley was not less competitive in the presence of disease than in its absence. Competitive relationships between the species were more important for yield determination than the direct influence of the disease. Over three years the yield increase of the mixtures compared with the means of pure components was close to 5%, whereas extreme conditions in one year led to a decrease of 11%. The role of competition for yield determination in barley-oats mixtures under disease conditions is emphasized. 相似文献
69.
Lauri V. Punto MD ScD DVM PhD Timo O. Nevalainen DVM MS Sirkka A. Wiljasalo MD ScD Ilkka V. O. Alitalo DVM PhD 《Veterinary radiology & ultrasound》1984,25(1):43-45
A dog with aspiration pneumonia was examined by computed tomography (CT) with 8-mm continuous scans of the chest. The results demonstrated that CT is a useful procedure for evaluating pneumonia, although high cost prevents its routine use. A normal littermate was examined, and normal structures of the chest and chest wall were compared. 相似文献
70.
Terrestrial arthropods are mainly exposed to pesticides by uptake from the substrate e.g. “residual” uptake, which depends on the bioavailability of the pesticide. The residual uptake of deltamethrin by female Oedothorax apicatus (Blackwall), a linyphiid spider, was studied in relation to dependence on soil cover, soil moisture, walking behaviour, time after spraying and deposition rate. C14-labelled deltamethrin was used to quantify the uptake processes. Data were analysed using multiple regression analysis. Uptake was markedly higher from soil covered with fungi or moss than from uncovered soil. From uncovered soils with moisture contents varying from 7 to 49% dry weight, low uptake was measured, while at 63% moisture, the uptake was high. The bioavailability half-life was 157 min. The rate of uptake decreased with distance walked. The possible consequences of these results for field experiments are discussed. 相似文献