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61.
It is predicted that dryland salinity will affect up to 17 Mha of the Australian landscape by 2050, and therefore, monitoring the health of tree plantings and remnant native vegetation in saline areas is increasingly important. Casuarina glauca Sieber ex Spreng. has considerable salinity tolerance and is commonly planted in areas with a shallow, saline water table. To evaluate the potential of using the nitrogenous composition of xylem sap to assess salinity stress in C. glauca, the responses of trees grown with various soil salinities in a greenhouse were compared with those of trees growing in field plots with different water table depths and groundwater salinities. In the greenhouse, increasing soil salinity led to increased allocation of nitrogen (N) to proline and arginine in both stem and root xylem sap, with coincident decreases in citrulline and asparagine. Although the field plots were ranked as increasingly saline-based on ground water salinity and depth-only the allocation of N to citrulline differed significantly between the field plots. Within each plot, temporal variation in the composition of the xylem sap was related to rainfall, rainfall infiltration and soil salinity. Periods of low rainfall and infiltration and higher soil salinity corresponded with increased allocation of N to proline and arginine in the xylem sap. The allocation of N to citrulline and asparagine increased following rainfall events where rain was calculated to have infiltrated sufficiently to decrease soil salinity. The relationship between nitrogenous composition of the xylem sap of C. glauca and soil salinity indicates that the analysis of xylem sap is an effective method for assessing changes in salinity stress in trees at a particular site over time. However, the composition of the xylem sap proved less useful as a comparative index of salinity stress in trees growing at different sites. 相似文献
62.
Zusammenfassung Nach einem kurzen Überblick über die gesetzlichen Grundlagen für die Durchführung der Pflanzenbeschau wird über die Ergebnisse der Kontrollmaßnahmen bei der Einfuhr von Pflanzenerzeugnissen (Getreide) nach Berlin (West) berichtet. Von 1980 bis 1985 wurden insgesamt mehr als 700 000 Tonnen Weizen, Braugerste, Roggen, Hafer, Sonnenblumenkerne, Hirse und Erdnüsse aus 12 europäischen, amerikanischen und afrikanischen Ländern eingeführt, davon mehr als 99% allein aus der DDR.Die Importe aus der DDR waren im Durchschnitt zu knapp 1% mit Vorratsschädlingen befallen, und zwar mit dem Reiskäfer (Sitophilus oryzae L.), dem Gemeinen Kornkäfer (Sitophilus granarius L.), Leistenkopfplattkäfern (Cryptolestes spp.), dem Amerikanischen Reismehlkäfer (Tribolium confusum Duv.) und dem Rotbraunen Reismehlkäfer (Tribolium castaneum Hbst.).
Mit 2 Abbildungen und 3 Tabellen 相似文献
Stored products activities of the plant protection office Berlin. The inspection of imported stored products from 1980 to 1985
A brief survey is given about the legal basis for the inspection of stored products (cereals) imported to Berlin (West). This follows a report about the results of those controls. From 1980 to 1985 more than 700,000 tons of wheat, barley, reye, oats, sunflower seeds, millet and peanuts were imported from 12 European, American and African countries, more than 99% of them from the GDR.On average about 1% of the imports from the GDR were infested by stored product pests; there were rice weevil (Sitophilus oryzae L.), grain weevil (Sitophilus granarius L.), grain beetles (Cryptolestes spp.), confused flour beetle (Tribolium confusum Duv.) and red flour beetle (Tribolium castaneum Hbst.).
Mit 2 Abbildungen und 3 Tabellen 相似文献
63.
Journal of Pest Science - Slugs are a serious pest of cereal crops, and recent emphasis in slug pest management has shifted from solely chemical towards integrated approaches. The objective of the... 相似文献
64.
Keaton Schmidt Cindy Feng Tingxuan Wu Tanya Duke-Novakovski 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(9):961
Neonatal mortality rate (NMR) may be affected by maternal physical condition, anesthesia, and uterine incision or en-bloc neonate removal. The association of selected factors with number of dogs with dead puppies at hospital discharge was evaluated using 78 records. Data obtained at admittance for emergency cesarean section included: age, small or large body size, rectal temperature, packed cell volume, serum total protein, blood urea nitrogen, glucose, puppy in pelvic canal, and heart rate. Administration of opioids, propofol, alfaxalone, isoflurane, and sevoflurane, and anesthesia/surgical times and surgical technique were evaluated using Fisher’s exact tests. There were 238 live puppies and 38 dogs had 58 dead puppies; the NMR was 19.6%. Mortality was associated with puppy in the pelvic canal (P = 0.003) and duration of anesthesia > 80 minutes (P = 0.029). Age > 8 years (P = 0.054) and induction time to start of surgery > 30 minutes (P = 0.17) may be associated with mortality. Expedient cesarean section with obstructive dystocia and an induction time to start of surgery < 30 minutes are important for puppy survival. 相似文献
65.
The impact of feeding, fish size (body weight from 18.5 to 56.5 g) and water temperature (20 and 23 °C) on oxygen consumption (OC, mg O2 kg–1 h–1) and ammonia excretion (AE, mg TAN kg–1 h–1) was studied in Eurasian perch held in recirculation systems. OC for both fed and feed-deprived (3 days) fish was higher at 23 °C (278.5 and 150.1 mg O2 kg–1 h–1) than at 20 °C (249.3 and 135.0 mg O2 kg–1 h–1; P < 0.01). AEs for both fed and feed-deprived fish were also significantly higher at 23 °C than at 20 °C (P < 0.001). Water temperature and fish size had a significant impact on the oxygen:feed ratio (OFR, kg O2 kg–1 feed fed day–1) and ammonia:feed ratio (AFR, kg TAN kg–1 feed fed day–1; P < 0.001). Their average values at temperatures of 20 and 23 °C were 0.17 and 0.19 kg O2 kg–1 feed fed day–1 and 0.009 and 0.011 kg TAN kg–1 feed fed day–1, respectively. 相似文献
66.
Dennis Rubbenstroth Volker Schmidt Monika Rinder Marko Legler Victor Max Corman Peter Staeheli 《Veterinary microbiology》2014,168(2-4):318-323
Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes).During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for “estrildid finches”). 相似文献
67.
Effect of selected metrological parameters of dyed polyester textiles on their UV-barrier properties
This paper presents the results of studies on the effect of some metrological parameters of polyester textiles dyed with a disperse dye, C. I. Disperse Red 54, on the level of their UV-barrier properties. It has been found that the UV-barrier properties of textiles not always depend on fabric parameters such as thickness and tightness/porosity as suggested by many research works. The parameters mentioned above, due to their interaction with a dye applied (that absorbs UV radiation), one may treat as indirect factors. It is the surface weight of a fabric that seems to be the direct factor and the most important metrological parameter in this regard. This is indicated by spectrophotometric measurements of dyed fabrics of different surface weights. Higher values of this parameter result in higher levels of UV-barrier properties. Increase in the barrier properties with increasing dyeing percentage is also higher for fabrics with greater surface weights. To confirm this fact, we presented in this paper a physical-mathematical model accepted for a dyed woven fabric, treated as an optical filter containing a dye. The model is based on Lambert-Beer’s law. The dye plays the part of a UV radiation absorber, occurring in the fiber material in the state of monomolecular dispersion (a solid solution). 相似文献
68.
Pablo Aran Pablo Aguilar Thomas Bowen Matthew Farson Joseline Tapia Lara Vimercati John L. Darcy Adam J. Solon Dorota Porazinska Steven K. Schmidt Cristina Dorador 《水产资源保护:海洋与淡水生态系统》2021,31(8):2293-2299
- High elevation lakes are extreme ecosystems and serve as sentinels of various global changes.
- An expedition to Volcán Llullaillaco in 1996 discovered an unstudied high-elevation lake (6,170 m a.s.l.) that probably was formed as a result of the past eruptive events or climatic processes such as glacial retreat in the lake basin.
- This article describes an initial physical characterization of the lake and its microbial communities derived from two sampling expeditions in 2013 and 2016.
- The microbial community in the lake, with an area between 1.2 and 1.4 ha and a depth of 6.8 m, was dominated by Proteobacteria, Actinobacteria and Haloarchaea. In addition, 26 bacterial isolates were identified within the genera Subtercola, Xylophilus, Rhodanobacter, Mesorhizobium and Pseudomonas.
- Lago Llullaillaco is one of the highest recorded lakes in the world, and this study highlights the unique microbial diversity of this aquatic ecosystem and the importance of its preservation to understand the complex biological processes under polyextreme conditions.
69.
Patrick D. Armitage Krzysztof Szoszkiewicz John H. Blackburn Ian Nesbitt 《水产资源保护:海洋与淡水生态系统》2003,13(2):165-185
- 1. Chalk stream floodplains are extensively managed and the high degree of connectivity associated with water meadows has been severely reduced. The main contributor to aquatic biodiversity is perceived to be the river itself. Ditches in these areas have been largely ignored as a contributor to total diversity.
- 2. Separate surveys of instream, bankside and ditch macroinvertebrates in a small area of floodplain provided a unique opportunity to assess the relative contribution of each locality to total aquatic diversity. The fauna and flora of a ditch on the lower River Frome floodplain was examined and compared with studies of adjacent bankside and instream habitat. A total of 145 macroinvertebrate taxa and 61 plant species were recorded from the ditch. Faunal abundance and richness were positively related to the diversity of aquatic plants. The ditch showed a clear linear trend in community type that appeared to be partly related to the acidic seepage from tertiary deposits at the source and percentage cover of vegetation.
- 3. There were large differences in the numbers of taxa collected in ditch, bankside, instream mesohabitat and RIVPACS surveys. Of the total 202 taxa recorded in the four surveys, the ditch contributed 59 unique taxa with 25 from the bankside and two and three from the mesohabitat and RIVPACS surveys, respectively.
- 4. The large contribution of the Rushton Ditch to aquatic biodiversity on the floodplain is due to three main factors: the chemically different and slow‐flowing environment, the connection to the main river, and a management regime which has halted hydroseral succession at a point where vegetation structure is for the most part open and able to support a wide range of ecological niches. The maintenance of these conditions requires sensitive management and further knowledge of the needs and interactions of faunal communities with vegetation.
70.
A pine forest was separated from a lake littoral zone by a meadow on one area (discontinuous) while these habitats were separated by a shrub strip in another area (continuous). This shrub strip acted as an ecological corridor enhancing the movements of birds between the forest and the littoral reed zone. The number of individuals of non-littoral species that visited the reed zone was higher (p < .001) on the area with the connecting shrub strip in autumn but the number of species visiting the littoral zone was not significantly higher. Significantly more (p < .001) autumn movements by birds in the continuous area were oriented along paths between the forest and the littoral zone whereas movements in the discontinuous area paralleled the littoral and forest zones (p < .001). Movements of birds were concentrated along the edge of the shrub strip. The spatial configuration of the landscape facilitated access by some forest birds to the littoral habitat. 相似文献