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131.
Changes in soil chemical and microbiological parameters in small (185 m2) and medium (410 m2) gaps, created in mature silver fir (Abies alba Mill) stands (mean height 30 m) in the Calabrian Apennines (Southern Italy), were studied over 2 years. Medium gaps had high soil temperature and photosynthetically active radiation (PAR) transmittance and low soil moisture. Within small gaps we detected a greater amount of organic matter, with respect to under canopy cover sites and medium gaps. Moreover, a different trend of the organic matter between small and medium gaps was observed. In the medium gaps, with respect to under canopy cover sites and small gaps, we found a relatively low content of organic matter, associated to a lower amount of humic acid, which suggested that the organic substrate undergoes a mineralization rather than a humification process. An opposite trend was observed in small gaps, where the increase of organic matter content, associated to an increase of humic acid and microbial biomass, suggested a better humification process. Moreover, in small gaps the highest level of urease and the greatest fluorescein diacetate (FDA) hydrolysis were observed. The different trend of organic matter observed in small and medium gaps may be related to changes in the environmental conditions. PAR transmittance, significantly higher in medium gaps, contributed to increase soil temperature and decrease soil moisture, affecting soil microbial populations and organic matter trend. These results suggest that the creation of small gaps represents the silvicultural practice with minor environmental impact.  相似文献   
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133.
Zusammenfassung In einem kombinierten Düngungs- und Infektionsversuch wurden die Beziehungen zwischen dem Ern?hrungszustand, dem Wachstum und der Rotf?uledisposition von N-Mangel-Fichten auf Kalkmergel-Rendzina geprüft. Die vorliegende Arbeit berichtet über die Wirkung der N-Düngung und künstlicher Infektionen mit Heterobasidion-Mycel auf den Gehalt an Extraktstoffen im Bast und Holz. Wurzelbast vom August (nicht aber vom April) von mehrmals gedüngten Fichten enthielt mehr Chloroform-und Ethanol/Wasser-Extrakt sowie Zucker- und Phenolkomponenten als die ungedüngten Varianten. Auch das Wurzelholz gedüngter Fichten war im August reicher an Extraktstoffen. Die N-Gaben steigerten au?erdem in beiden Geweben den Gehalt an l?slichen N-Verbindungen. Im Stamm erh?hte die Düngung die Gehalte an. Methanol-Extrakt sowie an einigen N-haltigen und phenolischen Verbindungen nur im ?u?eren Splint. Die Inokulation der St?mmchen durch Anbohren induzierte die Bildung von Reifholz und übergangszonen (zwischen Splint und verf?rbtem Reifholz), die besonders reich an Petrolether-Extrakt, Methanol-Extrakt und Lignanen waren. Diese Reaktionen der Fichten waren durch Düngung nicht beeinflu?t, da sie in inneren, vor der Düngung angelegten Stammbereichen abliefen. Die wiederholte N-Düngung führte im Wurzelbast vom April zu geringerer, in den August-Proben zu gesteigerter Hemmwirkung gegenüber Heterobasidion annosum im Biotest. Die Hemmung im August war mit dem Gehalt an phenolischen Komponenten positiv korreliert. Wurzelholz und ?u?erer Stamm-Splint von gedüngten B?umchen enthielten mehr Stickstoff und mehr Aminos?uren als die Kontrollfichten und stellten deshalb ein besonders günstiges, Substrat für den Pilz dar. Die Hemmwirkung des Reifholzes war positiv korreliert mit dem Gehalt an Methanol-Extrakt bzw. an Lignanen; ein Düngungseinflu? war nicht erkennbar. Für Stammholzfraktionen der inokulierten Fichten fand sich ein positiver Zusammenhang zwischen der Hemmwirkung und dem Gehalt an harzartigen Komponenten, die als Reaktion des Baumes auf die Verletzung vermehrt produziert wurden.
Nitrogen fertilization experiments in a Norway spruce stand (Picea abies Karst.) of stagnant growth on devastated marly rendzina: III. Influence of fertilization and inoculation on the extractives in phloem and wood
Summary A combined fertilization and inoculation experiment was designed to study the interrelationships between nutritional status, growth, and susceptibility to heart rot of planted N-deficient Norway spruce growing on a rendzina soil (Rendoll). The present report describes the impact of N-fertilization and of inoculation withHeterobasidion annosum mycelium on the contents of extractives in the phloem and in the wood. Root phloem in August (but not in April) of spruces fertilized repeatedly contained more chloroform- and ethanol/water-soluble substances, and more sugars and phenolic compounds as compared with phloem from the controls. Root wood of fertilized trees was also richer in extractives. N-fertilization, in addition, always raised the contents of soluble N-fractions in both tissues, as well as the amount of methanol-soluble substances, N-containing compounds, and phenolics in the outer sapwood region of the stem. Inoculation of stems by introducingH.a. mycelium into auger holes induced the formation of heartwood and of transition zones (between sapwood and heartwood) which were especially rich in petrolether- and methanol-soluble substances and in lignans. These reactions were not influenced by fertilization, since they were located in the inner stem regions formed in advance of fertilization. Repeated N-application reduced the fungistatic effect onH.a. of root phloem in April but increased it in August. The inhibition in August was positively correlated with the contents of phenolic compounds. Root wood and outerstem sapwood of fertilized spruces were richer in N and amino acids than control trees and therefore offered a favorable substratum for the fungus. The inhibitory effect of heartwood was positively related to the content of methanol-soluble compounds and lignans; an effect of fertilization could not be found. For wood fractions of inoculated trees a positive interrelationship was detected between fungistatic effect and content of resin compounds, the production of which was promoted as a reaction of the tree to wounding.
  相似文献   
134.
Traditional phytotherapy in Central Italy (Marche, Abruzzo, and Latium)   总被引:2,自引:0,他引:2  
In this study, the more significant results of extensive ethnopharmacobotanical research carried out by the author in the years 1977-2000 in 175 localities of three regions of Central Italy (Marche, Abruzzo, and Latium) have been reported and compared. The usages of 80 species belonging to 36 families are described, of which 71 were used in human therapy and 29 in veterinary medicine. Uses are suited with the number of localities in which they have been mentioned. Among the wild plant mainly still used, Malva sylvestris, Urtica dioica, and Sambucus nigra are particularly highly considered, while major uses of plants concern these plants in addition to Allium sativum, Rubus ulmifolius, Parietaria diffusa, Cynodon dactylon, and Ficus carica. Unusual phytotherapic uses concern Brassica oleracea, Taraxacum officinale (warts), Ruscus aculeatus, S. nigra (chilblains), Allium cepa (chilblains; to remove thorns and splinters), Juglans regia, R. ulmifolius (burns), and Euphorbia paralias (bites of weevers). Among new uses with only one quotation, we remember Cirsium arvense (intestinal disturbances), Centaurea bracteata (cough), Lupinus albus (calluses), Melittis melissophyllum (eye inflammations, antispasmodic), and Artemisia absinthium (tendon inflammations), while among plants employed in various regions with interesting less-known properties, there are C. arvense (emergency haemostatic), P. diffusa (insect bites), and Scrophularia canina (antiseptic and cicatrizing agent for wounds in bovines and sheep).  相似文献   
135.
136.
The Brazil nut tree(Bertholletia excelsa) is a frequent component of agroforestry systems in the Amazon because of its adaptation to nutrient-poor upland soils and multiple uses.We investigated the aboveground biomass production(kg dry weight),nutrient uptake and requirements(N,P,Ca,Mg,K) of Brazil nut trees of different sizes grown under agroforestry conditions and fertilized at different levels.Eight of 70 experimental trees with different size were harvested and stem,branches and leaves were separated.Nutrient contents were determined for three trees of varying size.Average tree growth was fast,but variability was high,suggesting considerable potential for the improvement of this economically important species.The trees responded to increased levels of fertilizer and lime with significantly increased foliar nutrient contents and growth,probably because of the improved availability of Mg and Ca for which the species seems to have a relatively high demand.In contrast to Brazil nut trees grown in forest or dense plantations,the agroforestry trees invested a substantial part of their biomass and nutrients in large branches and developed spreading crowns.To improve stem form,reduce competition with associated crops for light and recycle nutrients,regular pruning of lower branches or planting arrangements that favor self-pruning are recommended.These measures would also increase the recycling of Ca and Mg,large quantities of which are contained in the branches.  相似文献   
137.
Primary pulmonary neoplasia is relatively uncommon in cats and generally has a poor prognosis. In this multicenter, retrospective study of 57 cats with pulmonary neoplasia, the most frequent presenting signs were anorexia/inappetence (39%) and cough (37%). The pulmonary tumors were considered to be incidental findings in 9% cats. In computed tomographic (CT) images, primary pulmonary tumors appeared as a pulmonary mass in 55 (96%) cats and as a disseminated pulmonary lesion without a defined mass in two (4%) cats. Most pulmonary tumors were in the caudal lobes, with 28 (49%) in the right caudal lobe and 17 (30%) in the left caudal lobe. CT features associated with pulmonary tumors included mass in contact with visceral pleura (96%), irregular margins (83%), well‐defined borders (79%), bronchial compression (74%), gas‐containing cavities (63%), foci of mineral attenuation (56%), and bronchial invasion (19%). The mean (range) maximal dimension of the pulmonary masses was 3.5 cm (1.1–11.5 cm). Additional foci of pulmonary disease compatible with metastasis were observed in 53% cats. Pleural fluid was evident in 30% cats and pulmonary thrombosis in 12% cats. The histologic diagnoses were 47 (82%) adenocarcinomas, six (11%) tumors of bronchial origin, three (5%) adenosquamous cell carcinomas, and one (2%) squamous cell carcinoma. In this series, adenocarcinoma was the predominant tumor type, but shared many features with less common tumor types. No associations were identified between tumor type and CT features. Prevalence of suspected intrapulmonary metastasis was higher than in previous radiographic studies of cats with lung tumors.  相似文献   
138.

Background

Although modern commercial poultry production today is based on large farms and intensive husbandry, keeping backyard poultry has regained popularity in industrialized countries. However, the health status of backyard flocks is still relatively poorly documented. A questionnaire was sent to the owners of 376 backyard poultry flocks (<500 birds) in order to study health management procedures and characterize backyard poultry populations in Finland. Information was also collected on the postmortem findings from non-commercial flocks using necropsy data from the Finnish Food Safety Authority (Evira).

Results

Backyard flocks in Finland are small in size (<50 birds), comprising mainly chickens. Based on the results of the questionnaire, the health of such flocks is good, mortality low and vaccinations are not commonly used. Most of the flocks were registered in the national poultry register. The standard biosecurity practices are not generally applied and contact with wild birds, pets and farm animals is frequent, which can make the flocks more prone to infectious diseases. We conducted an 11-year retrospective study of the postmortem necropsy findings of the Evira in order to document the diseases, which caused mortality in backyard chickens in Finland. Necropsy was performed on a total of 132 non-commercial laying hens during 2000 – 2011. The most common postmortem findings were Marek’s disease (27%) and colibacillosis (17%).

Conclusions

This study is the first to report data on characteristics of and management practices for backyard chicken flocks in Finland. Close connections with commercial flocks are rare and farms are usually distantly located suggesting that the risk that these backyard flocks pose to commercial poultry is low.  相似文献   
139.
140.
Avian influenza outbreaks have occurred during winter months, and effective disinfection of poultry premises at freezing temperatures is needed. The commercial disinfectants Virkon and Accel, supplemented with an antifreeze agent [propylene glycol (PG), methanol (MeOH), or calcium chloride (CaCl2)], were evaluated for their effectiveness in killing avian influenza virus (AIV) at −20°C or 21°C. An AIV suspension was applied to stainless steel disks, air-dried, and covered with a disinfectant or antifreeze agent for 5 to 30 min. Virkon (2%) and Accel (6.25%) with 30% PG, 20% MeOH, or 20% CaCl2 inactivated 6 log10 AIV within 5 min at −20°C and 21°C. At these temperatures PG and MeOH alone did not kill AIV, but the 20% CaCl2 solution alone inactivated 5 log10 AIV within 10 min. The results suggested that CaCl2 is potentially useful to enhance the effectiveness of disinfection of poultry facilities after outbreaks of AIV infection in warm and cold seasons.  相似文献   
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