| 1. |
- Johansson, B, et al.
(författare)
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Effects of Tris on vascular smooth muscle
- 1979
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Ingår i: American Journal of Physiology - Heart and Circulatory Physiology. - 1522-1539. ; 237:3, s. 409-411
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Bååth, Erland, et al.
(författare)
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Effect of nitrogen and carbon supply on the development of soil organism populations and pine seedlings - microcosm experiment
- 1978
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Ingår i: Oikos. - 1600-0706. ; 31:2, s. 153-163
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Tidskriftsartikel (refereegranskat)abstract
- Series of pots containing Scots pine seedlings and a humus-sand mixture were watered twice weekly for 398 d with different nutrient solutions (control treatment with complete plant nutrient solution less nitrogen; glucose addition; nitrogen addition; glucose and nitrogen addition). Analyses were made of organic and nitrogen contents in the substrate, plant weights and nitrogen contents, nitrogen fixation and respiration rates, abundance, biomass and in some cases species composition of different soil organism populations. The growth rate of pine seedlings was lowest in series supplied with glucose, which is most easily explained by a deficiency of nitrogen due to microbial immobilization. The fungi and yeast were stimulated by addition of an easily available carbon source whereas the bacteria needed both nitrogen and carbon to maintain high biomass. A positive correlation between fungal feeding soil organisms and amount of fungal mycelium was found while a more complex situation prevailed with regard to bacterial numbers and bacterial feeding nematodes. The systems are evaluated in relation to the different treatments and compared with the field situation.
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| 3. |
- Berg, B., et al.
(författare)
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Fungal biomass and nitrogen in decomposing scots pine needle litter
- 1979
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Ingår i: Soil Biology & Biochemistry. - 0038-0717. ; 11:4, s. 339-341
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Tidskriftsartikel (refereegranskat)abstract
- The development of fungal biomass and increase of amounts of N was studied in decomposing pine needle litter for about 3 yr. After a relatively rapid increase of the amount of mycelium the fungal biomass became rather constant after about 2 yr. The absolute amount of N in the needles increased between the 4th and the 16th months and this increase was correlated to the increase of fungal biomass in the needles.
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| 4. |
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Bååth, Erland, et al.
(författare)
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Effects of artificial acid rain on microbial activity and biomass
- 1979
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Ingår i: Bulletin of Environmental Contamination and Toxicology. - 0007-4861. ; 23:6, s. 737-740
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Tidskriftsartikel (refereegranskat)abstract
- The emission of air pollutants which form acid components in rain and snow represents a threat to natural ecosystems. Increased leaching of nutrients from soils (ABRAHAMSEN et al. 1976b), decreased pHvalues in lakes and changes in fish populations (SCHOFIELD 1976) have been suggested as some of the consequences of the increased acidity of rain. Scandinavian coniferous forests are very stable ecosystems, and dramatic short-term effects due to acid rain are hardly to be expected. To simulate long-term effects, artificially acidified rain may be used. We report here decreased microbial activity and biomass in a Norwegian forest soil treated with artificially acidified rain.
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| 9. |
- Dahlgren, T., et al.
(författare)
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Electronic spectra of dithieno analogues of phenanthrene
- 1979
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Ingår i: Chemical Physics. - : Elsevier BV. - 0301-0104. ; 40:3, s. 397-404
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic circular dichroism (MCD) spectra of some dithieno analogues of phenanthrene: benzo [2,1-b;3,4-b′] dithiophene (I) benzo [1,2-b;4,3-b′] dithiophene (II), benzo [1,2-c;3,4-c′] dithiophene (III) and benzo [1,2-b;3,4-b′] dithiophene (IV) are reported. For I–III the spectra corresponding to two different transition moment directions could be obtained from low-temperature linear dichroism spectra. The results compare well with theoretical energies, oscillator strengths, moment directions and MCD B-terms which were obtained from semi-empirical quantum mechanical calculations in the π-electron approximation.
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| 10. |
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