| 1. |
|
|
| 2. |
|
|
| 3. |
- Förlin, Lars, 1950, et al.
(författare)
-
Effektscreening –Biologisk effektövervakning i förorenade områdenlängs Sveriges kust2017–2018
- 2019
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Undersökningarna visar att samtliga metoder inklusive undersökningar av hälsotillståndet hos fisk, fortplantning och biomarkörer hos vitmärla, lysosomal membranstabilitet hos mussla och imposex hos snäckor med få undantag visade på tydliga effekter i de åtta undersökta och förorenade områdena längs Sveriges kuster. En jämförelse mellan de olika metoderna visar, med undantag för området i Uddevalla/Byfjorden, en tydlig påverkan i resterande undersökta områdena. I Byfjorden noterades mindre stressade musslor och endast låga stadier av imposex hos snäckor medan fiskhälsan kunde konstateras vara påverkad. Utöver Byfjorden gjordes undersökningar med mer än en av metoderna även i Sundsvallsfjärden, Norrsundet, Bråviken, Ronnebyåns mynning och Landskrona. I dessa områden visar jämförelsen mellan metoderna att samtliga indikerar en tydlig påverkan. Att samtliga metoder ger utslag beror sannolikt på att alla valda undersökningsområden har en mycket komplex och ganska påtaglig föroreningsbelastning vilket innebär att det kan förväntas att de flesta organismer som lever i dessa områden kan uppvisa effekter som kan härledas till påverkan av miljöstörande ämnen. I Sverige är den nationella effektbaserade miljöövervakningen i marin miljö väsentligen inriktad på att undersöka effekter av miljögifter i referensområden. Sådana områden karakteriseras av att de ska ligga på stort avstånd från större befolkningscentra och industrier, eller till exempel inte ligga nära stora flodmynningar. Resultaten från denna studie kompletterar den ordinarie miljöövervakningen i referensområden och visar med stor tydlighet att de undersökta områdena är källor för miljöstörande ämnen till vattenmiljön. Undersökningarna visar också att det är önskvärt att kontinuerlig biologisk effektövervakning kommer igång i något eller några påverkade områden inom ramen för den nationella miljöövervakningen för att parallellt följa förändringar i miljön nära eller en bit från påtagliga, mer eller mindre kontinuerliga föroreningskällor i vårt samhälle. Detta skulle också komplettera Sveriges internationella rapportering av miljödata genom att förutom att rapportera effektdata från referensområden även kunna rapportera data från påverkade/förorenade områden.
|
|
| 4. |
- Adam, Birgit, et al.
(författare)
-
N2-fixation, ammonium release and N-transfer to the microbial and classical food web within a plankton community
- 2016
-
Ingår i: The ISME Journal. - : Springer Science and Business Media LLC. - 1751-7362 .- 1751-7370. ; 10:2, s. 450-459
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated the role of N2-fixation by the colony-forming cyanobacterium, Aphanizomenon spp., for the plankton community and N-budget of the N-limited Baltic Sea during summer by using stable isotope tracers combined with novel secondary ion mass spectrometry, conventional mass spectrometry and nutrient analysis. When incubated with 15N2, Aphanizomenon spp. showed a strong 15N-enrichment implying substantial 15N2-fixation. Intriguingly, Aphanizomenon did not assimilate tracers of 15NH4+ from the surrounding water. These findings are in line with model calculations that confirmed a negligible N-source by diffusion-limited NH4+ fluxes to Aphanizomenon colonies at low bulk concentrations (<250 nm) as compared with N2-fixation within colonies. No N2-fixation was detected in autotrophic microorganisms <5 mum, which relied on NH4+ uptake from the surrounding water. Aphanizomenon released about 50% of its newly fixed N2 as NH4+. However, NH4+ did not accumulate in the water but was transferred to heterotrophic and autotrophic microorganisms as well as to diatoms (Chaetoceros sp.) and copepods with a turnover time of ~5 h. We provide direct quantitative evidence that colony-forming Aphanizomenon releases about half of its recently fixed N2 as NH4+, which is transferred to the prokaryotic and eukaryotic plankton forming the basis of the food web in the plankton community. Transfer of newly fixed nitrogen to diatoms and copepods furthermore implies a fast export to shallow sediments via fast-sinking fecal pellets and aggregates. Hence, N2-fixing colony-forming cyanobacteria can have profound impact on ecosystem productivity and biogeochemical processes at shorter time scales (hours to days) than previously thought.
|
|
| 5. |
|
|
| 6. |
- Jung, Seungyoun, et al.
(författare)
-
Alcohol consumption and breast cancer risk by estrogen receptor status : in a pooled analysis of 20 studies.
- 2016
-
Ingår i: International Journal of Epidemiology. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 45:3, s. 916-928
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Breast cancer aetiology may differ by estrogen receptor (ER) status. Associations of alcohol and folate intakes with risk of breast cancer defined by ER status were examined in pooled analyses of the primary data from 20 cohorts.METHODS: During a maximum of 6-18 years of follow-up of 1 089 273 women, 21 624 ER+ and 5113 ER- breast cancers were identified. Study-specific multivariable relative risks (RRs) were calculated using Cox proportional hazards regression models and then combined using a random-effects model.RESULTS: Alcohol consumption was positively associated with risk of ER+ and ER- breast cancer. The pooled multivariable RRs (95% confidence intervals) comparing ≥ 30 g/d with 0 g/day of alcohol consumption were 1.35 (1.23-1.48) for ER+ and 1.28 (1.10-1.49) for ER- breast cancer (Ptrend ≤ 0.001; Pcommon-effects by ER status: 0.57). Associations were similar for alcohol intake from beer, wine and liquor. The associations with alcohol intake did not vary significantly by total (from foods and supplements) folate intake (Pinteraction ≥ 0.26). Dietary (from foods only) and total folate intakes were not associated with risk of overall, ER+ and ER- breast cancer; pooled multivariable RRs ranged from 0.98 to 1.02 comparing extreme quintiles. Following-up US studies through only the period before mandatory folic acid fortification did not change the results. The alcohol and folate associations did not vary by tumour subtypes defined by progesterone receptor status.CONCLUSIONS: Alcohol consumption was positively associated with risk of both ER+ and ER- breast cancer, even among women with high folate intake. Folate intake was not associated with breast cancer risk.
|
|
| 7. |
- Kolberg, D., et al.
(författare)
-
Effect of Rhizome Fragmentation, Clover Competition, Shoot-Cutting Frequency, and Cutting Height on Quackgrass (Elymus repens)
- 2018
-
Ingår i: Weed science. - : Cambridge University Press. - 0043-1745 .- 1550-2759. ; 66:2, s. 215-225
-
Tidskriftsartikel (refereegranskat)abstract
- Quackgrass is a problematic agricultural weed in the temperate zones of the world and is difficult to control without herbicides or intensive tillage. However, it may be possible to control quackgrass with less environmental impact by combining multiple low-intensity control methods. A pot experiment was conducted in July to October 2012 and repeated in June to September 2013 to investigate the effect of rhizome fragmentation, competition from white clover, shoot-cutting frequency, and cutting height on quackgrass. Rhizome fragmentation was expected to result in more, but weaker, quackgrass shoots that would be more vulnerable to shoot cutting and competition. However, by 20 d past planting, rhizome fragmentation did not change the total number of quackgrass shoots per pot, because an increase in main shoots was offset by a decrease in tiller numbers. Rhizome fragmentation did not reduce quackgrass biomass acquisition during the experimental period. Although rhizome fragmentation did reduce total fructan content, it did not enhance the effect of clover competition, shoot-cutting frequency, or shoot-cutting height. Clover competition by itself reduced quackgrass shoot numbers by 72%, rhizome biomass by 81%, and belowground fructan concentration by 10 percentage points, compared with no competition. The more frequently quackgrass shoots were cut, the less biomass quackgrass acquired, and a high shoot-cutting frequency (each time quackgrass reached 2 leaves) resulted in a lower belowground fructan concentration than a low shoot-cutting frequency (at 8 leaves). However, in pots without competition, a higher shoot-cutting frequency resulted in more quackgrass shoots. A lower shoot-cutting height (25 mm) had more impact when shoot cutting was more frequent. In conclusion, rhizome fragmentation did not reduce the number of quackgrass shoots or rhizome biomass, but competition from white clover, a high shoot-cutting frequency, and a low shoot-cutting height strongly suppressed quackgrass biomass and fructan acquisition.
|
|
