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31.
Zusammenfassung Aus dem Stadtgebiet von Hamburg wurden 341 Stra?enb?ume der GattungenAcer, Aesculus, Betula, Fraxinus, Platanus, Quercus, Robinia, Sorbus undTilia hinsichtlich ihrer Empfindlichkeit gegenüber Streusalz untersucht. Als Untersuchungsmethoden dienten Jahrring-analyse sowie Histometrie und energiedispersive R?ntgen-Mikroanalyse. Auf Standorten mit hohem Bodensalzgehalt zeigten die meisten B?ume seit Mitte der 60er Jahre Zuwachsrückg?nge von über 50%, was zu einer Verringerung der wasserleitenden Querschnittsfl?che in den St?mmen und vermutlich zu den Blattnekrosen in der Krone führte. Alle an streusalzbelasteten Stra?en lebenden Ahornb?ume, Linden und Ro?kastanien zeigten eine starke Vitalit?tsminderung. Lediglich die Eichen und Robinien lassen keine streusalzbedingten Wachstums?nderungen erkennen. Zur Erholung der gesch?digten B?ume sowie zur Sicherung der toleranten Baumarten müssen eine weitere Salzzufuhr verhindert und die bereits angereicherten Salzmengen aus dem Kreislauf Boden-Baum-Boden entfernt werden.
Wood-biological investigations on the influence of deicing salt on roadside trees in Hamburg
Summary From the urban area of Hamburg, 341 roadside trees of the generaAcer, Aesculus, Betula, Fraxinus, Platanus, Quercus, Robinia, Sorbus andTilia have been investigated concerning their sensitivity to deicing salt. The methods used were tree-ring analysis, histometrical studies, and X-ray microanalysis. Since the middle of the Sixties the radial growth of most tress decreased more than 50% on all sites with a high salt content in the soil, leading to a reduction of the water-conducting area in the stems. The necrosis of the leaves is presumably a result of this situation. All maples, horsechestnuts, and limes growing along roads affected by deicing salt showed a highly decreased vitality. Only oak and black locust do not exhibit any saltinfluenced growth responses. For the recovery of the injured trees as well as for safeguarding the more tolerant tree species a further salt transport to the roots must be prevented, and the amount of salt already accumulated must be removed from the soil-tree-soil cycle.


Wir danken Dr.H. Meyer-Spasche, Ordinariat für Bodenkunde der Universit?t Hamburg, für die Bereitstellung der bodenchemischen Standortsdaten, Prof. Dr.N. Parameswaran für die energiedispersive R?ntgen-Mikroanalyse sowie Frau Dipl.-HolzwirtS. Wrobel und FrauF. Quiehl für ihre Mithilfe bei der Laborauswertung. Die Arbeit wurde von der Beh?rde für Bezirksangelegenheiten, Naturschutz und Umweltgestaltung (BBNU) der Freien und Hansestadt Hamburg finanziell unterstützt. Die Baubeh?rde stellte Informationen über die Intensit?t der Streusalzanwendung zur Verfügung.  相似文献   
32.
Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid‐ and late‐lactation stages than non‐lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.  相似文献   
33.
Hemorrhagic septicaemia, an acute disease caused by P multocida capsular type B which is rarely detected in Europe, caused considerable losses in fallow deer, cattle and pigs within a region along the border of the federal states Brandenburg and Saxony-Anhalt in the summer of 2010. Clinical appearances and diagnostic findings are presented and possible triggering influences discussed. Pasteurella multocida capsular type B has not been cultivated from clinically healthy cattle and pigs of the region. Examination of fallow deer and roe deer in the region revealed the presence of singular carriers, which may act as a source of clinical infections.  相似文献   
34.
The aim of the study was to test Thymi herba (1.66% v/w essential oil with 39% p-cymene and 32% thymol) in the rearing period of piglets as feed additive. Therefore, two feeding trials were performed with piglet groups ranging from 17 to 22 animals each. Either 10 g of Thymi herba/kg feed (Thymi herba group), 10 mg flavophospholipol/kg feed (flavophospholipol group) or nothing (control group) was added to the animals' feed. No significant differences in the performance parameter daily weight gain among any groups were recorded. No differences concerning feed efficiency or isolation of haemolytic E. coli serotypes were shown. In addition, the antibacterial activity of the essential oil of Thymi herba against 39 haemolytic E. coli isolates from the same weaners was investigated in vitro by disk diffusion, minimum inhibitory concentration and bactericidal concentration testing. In contrast to the feeding results, the essential oil of the thyme batch fed showed antibacterial activity against all haemolytic E. coli investigated. This interesting antibacterial potential of Thymi herba prompts further investigations as to its value as feed additive.  相似文献   
35.
Immunohistochemical detection of lymphatic capillaries was performed in the periodontium of maxillary and mandibular cheek teeth from 6 horses (aged 3-23 years). Tissue sections of the periodontium were taken at 4 different horizontal levels along the long axis of the tooth. The specimens were processed for immunoreaction with anti-Prox1, in order to distinguish lymphatic endothelium from blood vascular endothelium. Lymphatic vessels were detected in all periodontal tissues except for the dental cementum. Lymphatic capillaries were most densely distributed in the gingiva compared to other tissues of the periodontium. Lymphatic capillaries were found most consistently in samples taken from the gingival and subgingival regions in all horses examined. Within these levels, the gingiva as well as the spongiosa of the maxillary and mandibular bone had the greatest incidence of lymphatic vessels. Considering the distinct distribution of the lymphatic capillaries in the periodontium of the maxillary and mandibular cheek teeth, two complementary lymphatic drainage pathways are proposed: (1) superficial lymph drainage via the gingiva, emptying into the mandibular lymph nodes; (2) deep lymph drainage via the mandibular and maxillary spongiosa, emptying into the mandibular and retropharyngeal lymph nodes, respectively.  相似文献   
36.
Road construction degrades large areas of indigenous vegetation. Better understanding of ecosystem restoration after degradation will require development and assessment of improved restoration techniques. The potential of natural revegetation based on propagules from topsoil as a restoration technique, to achieve succession towards indigenous vegetation, is not fully understood and accepted as an alternative method for vegetation establishment. The aim of this study was to evaluate this restoration technique by comparing different topsoils with respect to their potentials for revegetation and to describe the early succession on these topsoils by recording change in vegetation cover and the number of species.The study road RV23 is situated in south-east Norway and runs mainly through mixed, mostly coniferous forest. The topsoil (the upper 30 cm) was removed before road construction started, stockpiled during the construction period and then redistributed on the road verge afterwards. In 1999, 10 macroplots of 25 m2 were placed randomly on selected topsoils of different qualities, to represent the soil variation in the study area. The soil quality varied from organic-rich to organic-poor soils. Each macro plot contained four 1-m2 mesoplots in which the species composition was recorded in 2000 and 2001.Univariate statistical tests were applied to reveal change in vegetation cover between macroplots within 1 year and between years 2000 and 2001. Furthermore, statistical tests were used to reveal the change in single-species frequencies between the study years.Two years after deposition of topsoils, the vegetation cover was generally satisfactory from an aesthetical point of view. However, the variation in vegetation cover and species composition was considerable on different topsoils, reflecting both the local variation of the indigenous vegetation and the soil quality. A total of 121 species of vascular plants were recorded in all 10 macroplots, although not more than 59 species were found in one macroplot. Species composition and single-species frequencies changed considerably from the first year to the second. Among the 61 species that were recorded in more than five mesoplots, the frequency of 16 species increased and the frequency of 10 species decreased significantly (P<0.05). Most of the decreasing species can be considered as weed species and are not represented in the present indigenous vegetation, while most of the increasing species are. The vegetation change from 2000 to 2001 apparently represents the first steps in a succession towards an ecosystem dominated by species of the indigenous vegetation.  相似文献   
37.
In this longitudinal observational study, 118 growing Newfoundland dogs were followed with sequential radiographic examination of the right front limb, which were scheduled at ages 3, 4, 6, 12, 18, and 24 months to record evidence of skeletal changes. All affected dogs had evidence of changes at 6 months and dogs included in this study had radiographic examination at 6 months and at least two other scheduled examinations that included either 4 or 12 months. The dogs were privately owned and had individualized nutrition and environment with no maintenance protocol required by the project leaders. Irregularities in bone remodeling in the distal radius and ulna were seen in radiographs of 54 of 118 (45.8%) dogs. These irregularities differ from changes previously described in the Newfoundland dog. The reported irregularities were seen as islands of reduced opacity outlined by thickened, radiopaque osseous trabeculae, which were aligned with the axis of stress. All the 54 dogs with irregularities during some phase of development consistently had changes at 6 months of age. Reorganization of the changes in the bone was slow, and residual changes were visible at 18-24 months of age in many cases. The significance of these findings may lie in their potential for misinterpretation if they had been discovered in the presence of clinical signs such as any lameness or growth arrest. Radiographic appearance indicates disturbances in the bone maturation. The etiopathogenesis is unclear. Nutritional, environmental and genetic factors have to be studied.  相似文献   
38.
Here, we report results from a project where the aim was to study stress and mortality in the supply chain from harvest to market for live scallops Pecten maximus L., hand‐picked by scuba divers. With experiments conducted both during the warm (September) and cold (April) seasons, emphasis was put on how mechanical influence, stacking height, post‐harvest water storage and dry transport affected scallop fitness. When scallops were exposed to mild‐ or hard mechanical shocks (dropped three times from 50 or 150 cm), it was found that hard mechanical shock caused up to 90% mortality during subsequent water storage. Results from the experiments where scallops were stored at different stacking heights (15, 30 and 50 cm) in water showed that both the duration of storage and the stacking height had a significant effect on mortality. Higher stacking heights also affected survival in subsequent transport. For long‐term storage (>7 days), it is recommended to limit the stacking height of scallops stored in tanks to reduce risk of mortality. Respiration experiments showed an average oxygen consumption of 0.10 and 0.24 mg O2 min?1 kg?1 f.w. in the cold and warm season respectively. Water supply during storage of scallops should be adjusted to water temperature and biomass. Registration of mortality and analysis of the Adenylic Energy Charge of scallops followed through the production cycle from harvest to market indicate that it is the sum of stressors that are determinable for final survival.  相似文献   
39.
40.
Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the approximately 120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella.  相似文献   
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