Adaptive properties of Picea abies progenies are influenced by environmental signals during sexual reproduction     

Øystein Johnsen  Tore Skrøppa 《Euphytica》1996,92(1-2):67-71

Summary Several independent tests have shown that climate and weather during sexual reproduction influence the adaptive properties of the Picea abies progenies. This phenomenon is expressed in seed orchards established by moving parent trees, propagated as grafts, from north to south, from high to low elevation, or from outdoor to indoor greenhouse conditions. The progenies exhibit delayed flushing in the spring, later growth cessation of leader shoots in the summer, delayed bud-set, higher frequency of lammas shoots and delayed development of frost hardiness in the autumn compared to progenies reproduced in the colder native environment. The altered performance is persistent. We have found no effect on progenies of photoperiod and temperature treatments given to the males during meiosis and pollen production. However, when crosses were made in early spring (March), inside a heated greenhouse (short day, high temperature), the progenies are less frost hardy during cold acclimation than progenies from identical crosses performed in late spring (May; long day high temperature) in the greenhouse. The most hardy offspring were from crosses performed under outdoor conditions in May (long day, low temperature). These results indicate that some stages in reproduction, such as female meiosis, pollen tube growth, syngamy and early embryo development, are sensitive to temperature and/or photoperiod which then alter the phenotypic performance of the offspring. The most likely explanation is the existence of a regulatory mechanism affecting the expression of genes controlling adaptive traits. If this is true, it must have implications for the genetic interpretation of provenance differences in Norway spruce.  相似文献   

Heterogeneity of bacterial populations and pesticide degradation potentials in the unsaturated zone of loamy and sandy soils     

Finn P. Vinther  Lars Elsgaard  Ole S. Jacobsen 《Biology and Fertility of Soils》2001,33(6):514-520

Soil microbial processes play an important role in relation to pesticide pollution of groundwater, and may be strongly influenced by hydrological and geochemical properties. The consequences of such heterogeneous environments on bacterial biomass, enzymatic activities, carbon utilisation patterns, and pesticide mineralisation potentials in the unsaturated zone of a sandy loam and a coarse sandy soil profile were studied. In sandy loam soil profiles the number of bacteria decreased from 10⁹ cells g^-1 in the surface layers to about 10⁷ cells g^-1 at 1.5-5 m depth. Simultaneously, the hydrolysis of fluorescein diacetate and arylsulfatase activity decreased to below the detection limit at about 1.5 m depth, and carbon utilisation patterns showed that bacterial populations from surface soil were significantly different from those from 4 m depth. Bacterial biomass and activity in macropore soil tended to be slightly higher than in matrix soil, and the carbon utilisation patterns of bacterial populations extracted from macropore soil and from matrix soil seemed to be different. Maximally 3% of ¹⁴C-labelled mecoprop and isoproturon was mineralised in soil from the 1-1.5 m depth, and less than 1.5% was mineralised in soil from the 3.5-4 m depth. The macropore soil tended to have a higher degradation potential than the matrix soil. The total number of bacteria in the coarse sandy soil profile decreased from about 10⁸ in the plough layer to 10⁷ cells g^-1 at 0.4-2 m. The enzymatic activities and the degradation potentials of ¹⁴C-labelled mecoprop and isoproturon were significantly correlated (r² >0.79) and showed a distinct decrease at about 0.4 m. In addition to the depth variability, a horizontal heterogeneity in this soil was observed as horizons or compartments that differed in colour, i.e. with different chemical composition and concentrations of Fe and organic matter. Counts of viable bacteria and measurements of fluorescein diacetate hydrolysis and arylsulfatase activity confirmed a high variability of microbial biomass and activity in the sandy soil profile.  相似文献   

A general model for assessment of the carbon sequestration potential of afforestation projects   总被引：1，自引：0，他引：1  

Henrik Meilby  Finn Helles 《New Forests》2011,42(3):383-396

Among the objectives of afforestation projects, carbon sequestration is attracting increasing political attention. Therefore, there is a need for understanding the carbon sequestration ??mechanism?? and for ex-ante assessment of the sequestration potential of afforestation projects. Such assessment must be based on parameter estimates that are inherently uncertain, making the basis for applying an advanced sequestration model weak. This paper presents a transparent, simple and general model for quantification of the carbon sequestration in afforestation projects. The model can easily be modified so as to fit specific conditions, and it is held sufficiently reliable when taking into account the ex-ante character of the decision problem. The use of the model is exemplified by application to a yield table for Sitka spruce. Limitations of the model framework and its application in combination with scenarios of climate change are discussed.  相似文献   

Soviet and post-soviet science     

Baker VR  Finn VS 《Science (New York, N.Y.)》1994,265(5170):301-302

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A new member of the leucine zipper class of proteins that binds to the HLA DR alpha promoter   总被引：42，自引：0，他引：42  

H C Liou  M R Boothby  P W Finn  R Davidon  N Nabavi  N J Zeleznik-Le  J P Ting  L H Glimcher 《Science (New York, N.Y.)》1990,247(4950):1581-1584

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In Situ Avoidance Response Of Adult Atlantic Salmon To Waste From The Wood Pulp Industry     

Eva B. Thorstad  Torbjørn Forseth  Ingar Aasestad  Finn ØKland  Bjørn Ove Johnsen 《Water, air, and soil pollution》2005,165(1-4):187-194

An accidental release of non-toxic waste from decommissioned wood pulp industry in the River Numedalslågen, Southern Norway, occurred in the upper part of the accessible stretches for anadromous fish during a study of migration behaviour of radio tagged Atlantic salmon (Salmo salar, n=32, body length 51–99 cm). The fish had completed the migration phase and initiated the resident phase characterised by little movement until spawning. When the wooden fibres and pulp were released, 16 of 32 (50%) salmon showed an immediate avoidance response. Six (19%) salmon moved upstream and 10 (31%) salmon moved downstream. Of the salmon moving downstream, eight (25%) moved all the way to sea (average 14.8 km). Four re-entered the River Numedalslågen, two entered a neighbouring river and two were not recorded later. Fish moving downstream but without moving to the sea, moved on average 5.3 km during the episode, whereas those moving upstream moved on average 6.7 km. All fish recorded after the episode (n=30) survived until the spawning season. The study demonstrates that fish in nature may show an evident avoidance response, even to non-toxic contaminants. For Atlantic salmon, the size of the spawning population may be reduced by fish leaving the river (13% left the river and never came back). Moreover, the dispersal of salmon to other rivers may increase, and the distribution of the spawning population within the contaminated river may shift.  相似文献   

Implication of Lake Water Residence Time on the Classification of Norwegian Surface Water Sites into Progressive Stages of Nitrogen Saturation     

Kaste  Øyvind  Stoddard  John L.  Henriksen  Arne 《Water, air, and soil pollution》2003,142(1-4):409-424

Seasonal behaviour of NO₃ ^- in surfacewater is often used as an indicator on a catchment's ability toretain N from atmospheric deposition. In this paper, weclassify 12 pristine sites (five streams and seven lakes) insouthernmost Norway according to the N saturation stageconcept. All examined sites were acid-sensitive and had annualmean NO₃ ^- concentrations in the range 6–36 μeqL^-1. At lake sites with relatively long water residencetimes, hydrology will have a damping effect on the seasonalNO₃ ^- oscillations in the outlet streams. Under givenrunoff conditions (1.0–2.2 m yr^-1), the seasonalNO₃ ^- pattern was clearly affected when lake:catchmentarea ratios exceeded 0.15 and the total residence time of lakesin the catchments exceeded 0.3 yr. In such cases, annualmean NO₃ ^- concentration rather than seasonalvariations may be the better indicator of N saturation. Toaccount for this we propose a set of supplementary criteria forsuch lake systems, defining limit values for annual meanNO₃ ^- concentrations within each stage class. Beforebeing applied on a broader scale, however, we recommend anexamination of additional lake-dominated catchmentsrepresenting a larger gradient in ecosystem types, N depositionlevels and hydrologic regimes. When applying the supplementarycriteria on the Norwegian sites, two were classified as stage 0(no saturation), five as stage 1 (early stage of saturation)and five as stage 2 (saturated – moderate N loss). No siteswere showing symptoms of stage 3, which characteriseswatersheds that are net sources of N, rather than sinks. Theresults indicate a great variability in N retention capacity inthe study region, despite the fact that many of the catchmentsexperience relatively uniform N deposition amounts and climaticconditions. This suggests that much of this variability must bedue to specific catchment characteristics as e.g. soil type,soil depth, and vegetation cover.  相似文献   

Navicular bone disease: Results of treatment using egg-bar shoeing technique     

L. C. ØSTBLOM  C. LUND  F. MELSEN 《Equine veterinary journal》1984,16(3):203-206

Although the diagnostic criteria of navicular disease are generally accepted in practice, their limitations are recognised. However, the authors believe that navicular disease per se is reversible and that only secondary changes like adhesions to the deep flexor tendon or spur formations are irreversible. This hypothesis is supported by the results presented of the effect of the application of an egg-bar shoe, which caused permanent cessation of signs of navicular disease in more than 50 per cent of treated cases. The egg-bar shoeing technique can be usefully applied in practice.  相似文献   

ULTRASONOGRAPHY OF THE EQUINE BICIPITAL TENDON REGION: A CASE HISTORY REPORT AND REVIEW OF ANATOMY     

Charles R.  Pugh  DVM  MS  Phillip J.  Johnson  BVSc  MS  Gregory  Crawley  DVM  MS  Susan T.  Finn  DVM  MS 《Veterinary radiology & ultrasound》1994,35(3):183-188

The equine shoulder region is difficult to investigate by conventional imaging modalities. Diagnostic ultrasound has proven valuable for investigation of soft tissue injuries of the human shoulder. In a horse with shoulder lameness, the authors employed diagnostic ultrasound to augment the use of conventional radiography. A defect in the subchondral bone layer of the medial humeral tuberosity, with adjacent bony fragments were clearly identified with ultrasound. Ultrasound was used for initial evaluation of the bicipital tendon and bursa. The technique was subsequently used to follow and evaluate the post-operative condition of the proximal cranial humerus, bicipital tendon and bursa in this patient. The bicipital regions of 2 immature and 3 adult normal horses were also examined with to illustrate the normal ultrasonographic anatomy of the cranial shoulder region.  相似文献   

Pyocephalus and gastritis in a polar bear (Thalarctus maritimus)     

J P Finn 《Journal of the American Veterinary Medical Association》1969,155(7):1086-1089

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