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991.
Thomas Wutzler Barbara Köstner Christian Bernhofer 《European Journal of Forest Research》2007,126(3):371-383
The Kyoto-protocol permits the accounting of changes in forest carbon stocks due to forestry. Therefore, forest owners are
interested in a reproducible quantification of carbon stocks at the level of forest management units and the impact of management
to these stocks or their changes. We calculated the carbon stocks in tree biomass and the organic layer including their uncertainties
for several forest management units (Tharandt forest, Eastern Germany, 5,500 ha) spatially explicit at the scale of individual
stands by using standard forest data sources. Additionally, soil carbon stocks along a catena were quantified. Finally, carbon
stocks of spruce and beech dominated stands were compared and effects of thinning intensity and site conditions were assessed.
We combined forest inventory and data of site conditions by using the spatial unions of the shapes (i.e., polygons) in the
stand map and the site map. Area weighted means of carbon (C) stocks reached 10.0 kg/m2 in tree biomass, 3.0 kg/m2 in the
organic layer and 7.3 kg/m2 in mineral soil. Spatially explicit error propagation yielded a precision of the relative error
of carbon stocks at the total studied area of 1% for tree biomass, 45% for the organic layer, and 20% for mineral soil. Mature
beech dominated stands at the Tharandt forest had higher tree biomass carbon stocks (13.4 kg/m2) and lower organic layer carbon
stocks (1.8 kg/m2) compared to stands dominated by spruce (11.6, 3.0 kg/m2). The difference of tree biomass stocks was mainly
due to differences in thinning intensity. The additional effect of site conditions on tree carbon stocks was very small. We
conclude that the spatially explicit combination of stand scale inventory data with data on site conditions is suited to quantify
carbon stocks in tree biomass and organic layer at operational scale. 相似文献
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Katharina Thieme Luis Mesquita Simona Lieberth Christian Dancker Marcus Georg Doherr Johanna Corinna Eule 《Veterinary ophthalmology》2023,26(2):135-144
Objective
There is limited knowledge regarding the safety and accuracy of ultrasound-guided retrobulbar nerve blocks in horses. The aim of this study was to compare these parameters between blind and ultrasound-guided injection techniques for the dorsal retrobulbar nerve block in horses.Methods
Equine cadaver heads were used to inject the retrobulbar space with contrast medium (CM). Injections were performed either blindly based on anatomic landmarks (blind group, n = 44) or under ultrasonographic guidance (US-group, n = 44), equally divided between an experienced and unexperienced operator. Needle position and distribution of CM were assessed with computed tomography imaging and evaluated by a board-certified veterinary diagnostic imager blinded to the technique. Safety and accuracy of both techniques were compared.Results
Ocular penetration was observed in two cases (n = 2/44) in the blind group but not in the US group (n = 0/44). No intrathecal, intraneural, or intravascular injections were seen in either group. Safety was significantly improved in the US group (p = .026). There was no statistically significant difference between the groups regarding the accuracy of the injection. Excellent accuracy was achieved more often with the ultrasound-guided technique (n = 11/22) than with the blind technique (n = 7/22) when performed by the unexperienced operator, but this difference was not statistically significant.Conclusion
To prevent globe-threatening complications and improve the safety of the injection, we recommend using the ultrasound-guided injection technique for the dorsal retrobulbar nerve block. 相似文献995.
Jarrige N Ducrot C Cazeau G Morignat E La Bonnardière C Calavas D 《Veterinary research》2007,38(3):505-516
In France, after the ban on meat and bone meal (MBM) in cattle feeding in June 1990, cases of Bovine Spongiform Encephalopathy (BSE) have continued to be detected in bovines born after that ban (called BAB cases). A case-control study was therefore carried out to determine the way these cases were contaminated. A multivariate conditional model was built adjusting for the production type of the animals and taking into account the herd size. The results confirmed that feeding cattle with proprietary concentrates was at risk for BSE, with an adjusted odds ratio of 6.8 (2.5; 18.7) for the consumption of less or three different proprietary concentrates and 17.6 (5.7; 54.8) for more than three, when comparing with no consumption of proprietary concentrates, considering feeding of bovines before the age of two. The results suggest that cross-contaminations by MBM in bovine concentrates have occurred after 1990. To a lesser extent, on-farm cross-contaminations, i.e. consumption by cattle of feedstuffs initially dedicated to other animals and which could legally contain MBM, have probably also existed, since the presence on farms of poultry fed purchased feed involved an increased risk of BSE with an odds ratio of 1.8 (1.1; 3.0). The use of milk replacers, which often incorporates animal fats, was also at risk with an odds ratio of 1.8 (1.0; 3.1). 相似文献
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Nutrient and mineral composition during shoot growth in seven species of Phyllostachys and Pseudosasa bamboo consumed by giant panda 下载免费PDF全文
A. L. Christian K. K. Knott C. K. Vance J. F. Falcone L. L. Bauer G. C. Fahey Jr S. Willard A. J. Kouba 《Journal of animal physiology and animal nutrition》2015,99(6):1172-1183
During the annual period of bamboo shoot growth in spring, free‐ranging giant pandas feed almost exclusively on the shoots while ignoring the leaves and full‐ height culm. Little is known about the nutritional changes that occur during bamboo shoot growth, if nutritional changes differ among species, or how these changes might influence forage selection. Our objective was to examine the nutrient and mineral composition during three phases of shoot growth (<60, 90–150 and >180 cm) for seven species of bamboo (Phyllostachys (P.) aurea, P. aureosulcata, P. bissetii, P. glauca, P. nuda, P. rubromarginata, Pseudosasa japonica) fed to captive giant pandas at the Memphis Zoo. Total dietary fiber content of bamboo shoots increased (p < 0.0001) from an overall species average of 61% dry matter (DM) at < 60 cm to 75% DM at shoot heights > 180 cm, while crude protein, fat and ash exhibited significant declines (p < 0.05). Phyllostachys nuda had the overall greatest (p = 0.007) crude protein (21% DM) and fat (4% DM) content, and lowest overall total fibre (61% DM) content compared to the other species examined. In contrast, Pseudosasa japonica had the overall lowest crude protein and fat, and relatively higher fibre content (9%, 3% and 74% respectively). Concentrations of Zn and Fe were highest in shoots <60 cm (10–50 μg/g DM) and decreased (p < 0.05) during growth in all species examined. Concentrations of Ca, Cu, Mn, Na and K varied among species and were largely unaffected by growth stage. Due to their higher concentrations of nutrients and lower fibre content in comparison to culm and leaf, bamboo shoots should be a major component of captive giant panda diets when available. 相似文献
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