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1.
Based on the results of the atmospheric deposition classification of the year 1989, a methodical approach should be introduced, which—based on the modelled total deposition rates—enables us to characterise the input situation of forest monitoring plots and to delimit load areas in Germany. In 1989, the deposition situation in nearly 1,800 forest monitoring sites (BZE/extensive Soil Condition Inventory) in Germany could be explained by four factors (or three, excluding sea salt impact) with the help of a factor analysis. The factor values were grouped into six deposition types with typical compounds and regional patterns. The classified input rates of the soil inventory plots adequately represent the stress situation and deposition changes in Germany. The application of the statistical approach on the level of Brandenburg clarifies the special local input situation. Due to the special combination of deposed elements, the sources of emissions can be characterised as well. When the soil inventory is repeated, a project planned for 2006, this approach can be used in order to determine homogenous areas for stratified data evaluation.  相似文献   
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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:
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This study investigated whether repeated administrations of adrenocorticotropic hormone (ACTH) during mid or late gestation, a treatment which induces endogenous cortisol release, affect growth performance, early vitality, open-field behaviour and immune responses of neonatal pigs. Administrations of ACTH (100 IU per animal, Synacthen® Depot) were given intramuscularly to gilts every second day either during mid (Day 49 until 75, Experiment 1) or late gestation (Day 85 until 107, Experiment 2). Control gilts received repeated injections of saline. The repeated ACTH stimulation of gilts during late gestation significantly reduced their daily weight gain during this period, but not when applied during mid gestation. Gestation length, number of born piglets and vitality measures of the newborn piglets, such as the rectal temperatures after birth and times elapsed between birth and first udder contact or milk uptake were not affected by the prenatal treatments. Administration of ACTH during late but not during mid gestation significantly increased the birth weights of piglets, and this difference in postnatal body weight was detectable until an age of 21 days. In addition, only the stimulation with ACTH during late gestation had an immunosuppressive effect on the lymphocyte proliferation of piglets 1 day after birth in response to the T-cell mitogen ConA and, in tendency, on the proliferation in response to the B-cell mitogen LPS. Twenty-four day old piglets from gilts treated during late gestation showed significantly more escape behaviour in an open-field than piglets from control litters. In conclusion, elevated maternal glucocorticoid levels during critical periods of prenatal development in pigs may affect prenatal growth, cell-mediated immunity and emotional reactivity in the neonatal piglets. The occurrence of these effects depends on the timing of increased maternal cortisol levels during gestation.  相似文献   
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To assess the possible degree of root competition from fruit trees which could potentially be used in agroforestry systems, fine root density of fruit trees Strychnos cocculoides Bak., Strychnos spinosa Lam. (Loganiaceae) and Vangueria infausta Burch. (Rubiaceae), as well as from the shrubby species, Grewia flava DC. (Tiliaceae) was investigated. Vangueria infausta had the highest fine root densities in both vertical and horizontal extensions. In Vangueria infausta fine root density decreased with increasing soil depth. For the other species in the 80 cm soil profile investigated, no significant changes in fine root density with soil depth were found. For Strychnos cocculoides almost no fine roots were detected in the upper soil horizon (0–20 cm). Using fine root surface area densities, exploration and exploitation indices were calculated. Vangueria infausta had the highest value of the exploration index compared to the other species. For use in agroforestry systems Vangueria infausta was estimated to be the most competitive of the investigated species, whereas Strychnos cocculoides seems to be the less competitive. Strychnos cocculoides has additionally spatial arrangements of fine roots favourable for agroforestry, slowly increasing with depth and additionally low concentrations in upper soil layers.  相似文献   
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European Journal of Forest Research - The article “Restrictions on natural regeneration of storm-felled spruce sites by silver birch (Betula pendula Roth) through limitations in...  相似文献   
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Calcium absorption from fumarate salts (calcium fumarate and calcium malate fumarate), which have recently been considered for use as sources for food and beverage enrichment, was compared to that from calcium citrate malate, calcium citrate, and calcium carbonate. Salts were instrinsically labeled with 45Ca and orally administered to Sprague-Dawley rats. Fractional absorption of calcium from each salt was determined using the femur uptake model. Fractional absorption from the five salts (0.30-0.27) was not significantly different (p > 0.05). Thus, when measured in the rat model, calcium from calcium fumarate and calcium malate fumarate is absorbed equally well as compared to other salts, which are common calcium sources in many foods, beverages, and supplements.  相似文献   
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Eight laboratories participated in a collaborative study to estimate precision of a standardized rat assay for determining true protein digestibility in selected animal, fish, and cereal products. Each of 7 test protein sources (casein, tuna fish, macaroni/cheese, pea protein concentrate, rolled oats, pinto beans, and nonfat dried milk) was fed as the sole source of protein at a 10% protein level in mixed diets. Each diet was fed to 2 replicate groups of 4 rats each for a 4-day acclimation period and a 5-day balance period. Mean digestibilities ranged from 98.6% for casein to 72.6% for pinto beans. Repeatability standard deviations ranged from 0.5 to 2.0%; the mean relative standard deviation for repeatability was 0.9% (range 0.5-2.8%). Reproducibility standard deviations ranged from 1.2 to 3.2%, and the mean relative standard deviation for reproducibility was 2.4% (range 1.3-4.4%). The method has been approved interim official first action for determining true protein digestibility in foods and ingredients.  相似文献   
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