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61.
62.
Zusammenfassung Es wird eine Schnellmethode zur Rauchh?rteprüfung von Kiefernarten beschrieben, die vom Terminaltrieb abgetrennte, in Pillengl?ser gesteckte einj?hrige Kurztriebe verwendet. Die Nadeln reagieren auf akute SO2-Immissionen kloneinheitlich und weitgehend in übereinstimmung mit der Mutterpflanze. Bei den Kurztrieben lassen sich endogene, vom Mutterbaum abh?ngige Differenzen in der Austrocknungsgeschwindigkeit nachweisen, die aber ohne wesentlichen Einflu? auf ihre Reaktion gegenüber SO2 bleiben, sofern die Expositionsdauer kurzgehalten wird. Die entwickelte Methode ist schneller, wirtschaftlicher und auch zuverl?ssiger als Rauchh?rteprüfungen mit eingetopften Pflanzen. Sie testet lediglich die Reaktion auf akute Begasungen.
Summary A short-time technique of testing pines for resistance against SO2-emissions has been developed, using one-year-old needle fascicles, put into water-filled glass vials. Against actual SO2-exposure, fascicles of the same tree react uniformly, and their reaction is very similiar to that of the parent tree. Besides, needle fascicles show endogenous clonal variation in the rate of drying out. This, however, does not influence the reaction against SO2, provided the time of exposure is kept short. The new technique is quicker, accurate, and more economical than SO2-tests with potted seedlings or graftings, but it only tests the reaction against short time-high doses exposure to SO2.


Durchgeführt mit finanzieller Unterstützung der Landesanstalt für Immissions- und Bodennutzungsschutz des Landes Nordrhein-Westfalen in Essen.  相似文献   
63.
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
Sabine AugustinEmail:
  相似文献   
64.
Wood Science and Technology - Several studies have dealt with the problem of how to measure the shear modulus of small clear wood specimens, avoiding bias from normal compression, bending, tension...  相似文献   
65.
The objective of this study was to determine the associations among Haemophilus parasuis, Mycoplasma hyorhinis, and porcine reproductive and respiratory syndrome (PRRS) virus (EU-field strain) infections in 95 pigs with polyserositis. A significant association between H. parasuis and M. hyorhinis was identified. H. parasuis and M. hyorhinis were significantly more often detected in PRRS virus positive pigs.  相似文献   
66.
67.
海南6种切叶花卉植物橡胶林下套种的适应性研究   总被引:1,自引:0,他引:1  
通过对散尾葵、金心巴西铁、金边富贵竹、莲花竹、龟背竹、朱蕉等6种耐荫型切叶花卉植物在橡胶林下进行套种(扦插)试验,观测这些植物的叶片生长物候期、植株整体感、株高、叶片色泽和病虫害危害程度,分析这6种切叶花卉植物在橡胶林下的生长适应性。结果表明,适应性强弱排序为金心巴西铁朱蕉散尾葵龟背竹莲花竹金边富贵竹,其中金心巴西铁在橡胶林下生长综合表现最好,评价得分最高,为17.22,适合在海南橡胶林下推广种植。  相似文献   
68.
Tea consumption is associated with a reduced risk of mammary cancer as reflected by epidemiological studies and experiments in carcinogen-induced rodent models of mammary carcinogenesis. We tested the hypothesis that green tea catechins (GTC) or theaflavins from black tea (BTT) interfere with mammary carcinogenesis in C3(1) SV40 T,t antigen transgenic multiple mammary adenocarcinoma (TAg) mice and that GTC/BTT affect tumor survival or oxidation status. TAg mice received GTC/BTT (0.05%) in drinking water for their lifetime. As compared to control mice, they survived longer and had smaller tumors. On microscopic inspection, the size of the largest tumor per mouse was decreased by 40-42% (p<0.01). GTC (0.01%) and BTT (0.05%) increased levels of cleaved caspase 3 in tumor tissue by 67 and 38%, respectively (p<0.05), intimating increased apoptosis. Tumor levels of the malondialdehyde-DNA adduct M1dG in mice receiving GTC or BTT (0.05%) were reduced by 78 (p<0.001) or 63% (p<0.05), respectively, as compared to controls. The results render the exploration of the breast cancer chemopreventive properties of tea preparations in humans worthwhile.  相似文献   
69.
OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design.  相似文献   
70.
A headspace sorptive extraction (HSSE) in combination with thermal desorption gas chromatography-mass spectrometry (TD-GC-MS) method for the analysis of volatile components (alcohols, esters, carbonyls, acids, phenols and lactones) in wine samples was developed. Extraction conditions such as salting-out effects, sorption time, stirring speed, phase ratio, extraction temperature, and effect of pH were thoroughly evaluated as part of method validation. The method was very sensitive with LODs and LOQs between 50 pg/L to 299 microg/L and 0.2 ng/L to 0.996 microg/L, respectively. Repeatability for all the compounds was between 3 and 22%. The intermediate repeatability was obtained within the acceptable range. Out of 39 volatile compounds selected, 37 were detected and quantitated. The method was found to be simple, cost-effective, sensitive, and use a small sample volume. The method was successfully applied for the routine analysis of 79 young red and white wine samples from various South African districts.  相似文献   
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