Carbon stock changes of forest land in Finland under different levels of wood use and climate change

Context

Prediction of the effect of harvests and climate change (CC) on the changes in carbon stock of forests is necessary both for CC mitigation and adaptation purposes.

Aims

We assessed the impact of roundwood and fuelwood removals and climate change (CC) on the changes in carbon stock of Finnish forests during 2007–2042. We considered three harvest scenarios: two based on the recent projections of roundwood and fuelwood demand, and the third reflecting the maximum sustainable cutting level. We applied two climate scenarios: the climate was in the state that prevailed around year 2006, or it changed according to the IPCC SRES A1B scenario.

Methods

We combined the large-scale forestry model MELA with the soil carbon model Yasso07 for mineral soils. For soils of drained, forested peatlands, we used a method based on emission factors.

Results

The stock change of trees accounted for approximately 80 % of the total stock change. Trees and mineral soils acted as carbon sinks and the drained peatland soils as a carbon source. The forest carbon sink increased clearly in both of the demand-based scenarios, reaching the level of 13–20 Tg C/year (without CC). The planned increase in the use of bioenergy reduced the forest sink by 2.6 Tg C/year. CC increased the forest carbon sink in 2042 by 38 %–58 % depending on the scenario. CC decreased the sink of mineral soils in the initial years of the simulations; after 2030, the effect was slightly positive. CC increased the emissions from the drained peatland soils.

Conclusions

It is likely that forest land in Finland acts as a carbon sink in the future. The changes in carbon stocks of trees, mineral soils, and peatland soils respond differently to CC and fuelwood and roundwood harvests.     

Influence of thaxtomins in different combinations and concentrations on growth of micropropagated potato shoot cultures

Plant-pathogenic Streptomyces species produce a variety of different phytotoxic 4-nitroindol-3-yl-containing 2,5-dioxopiperazines (thaxtomins) that induce scab symptoms on potato tubers (Solanum tuberosum). The possible mutual synergistic or antagonistic effects of thaxtomins are unknown. Modified methodology using column chromatography allowed the purification of thaxtomin A in large quantities (27 mg, HPLC purity of 97%). Thaxtomin A ortho isomer, thaxtomin B, and C-14 deoxythaxtomin B (thaxtomin D) were also purified. All four compounds induced similar symptoms of reduced root and shoot growth, root swelling (10-200 ppb), or necrosis (200-1000 ppb) on micropropagated in vitro cultures of potato. The scab-resistant potato cvs. Sabina and Nicola were more tolerant to thaxtomins than was the scab-susceptible cv. Matilda. Thaxtomins applied in combinations showed additive effects but no synergism, whereas thaxtomins A and B displayed antagonism with thaxtomin A ortho isomer.     

Elucidation of virus-host interactions to enhance resistance breeding for control of virus diseases in potato

Potato virus Y (PVY) and Potato mop-top virus (PMTV) are viruses whose geographical distribution is expanding and economic losses are increasing, in contrast to most of other viruses infecting potato crops. Most potato cultivars lack broad-spectrum resistance to the new, genetically complex strains of PVY, and no efficient resistance to PMTV is known in potato. Control of the vectors of these viruses is not an efficient or possible strategy to prevent infections. Studies on molecular virus-host interactions can discover plant genes that are important to viral infection or antiviral defence. Both types of genes may be utilized in resistance breeding, which is discussed in this paper. The advanced gene technologies provide means to fortify potato cultivars with effective virus resistance genes or mutated, non-functional host factors that interfere with virus infection.     

Polyphenol-rich phloem enhances the resistance of total serum lipids to oxidation in men

In humans, polyphenol supplementation studies have resulted in inconsistent findings in lipid peroxidation. Our aim was to investigate the effects of a 4-week consumption of polyphenol-rich phloem on serum lipids and lipid peroxidation in the hydrophilic fraction of serum and on isolated lipoproteins. We conducted a randomized double-blind supplementation study consisting of 75 nonsmoking hypercholesterolemic men. Participants consumed 70 g daily of either rye bread (placebo) or phloem-fortified rye bread containing 31 mg (low polyphenol, LP) or 62 mg (high polyphenol, HP) of catechins. The ex vivo susceptibility of total serum lipids and VLDL and LDL to oxidation after copper induction was measured as a lag time to the maximal oxidation rate at the baseline and after the supplementation. In the HP group, an increase in the oxidation resistance of total serum lipids was observed (11.4%), while no effect was seen in the LP group (-0.8%) or in the placebo group (-1.0%) (p = 0.007). No differences were observed in the oxidation resistance of VLDL and LDL between the study groups. The phloem also increased in vitro oxidation resistance of serum lipids and radical scavenging activity (DPPH.) in a dose-dependent manner. Our results suggest that polyphenols may inhibit lipid peroxidation in the hydrophilic fraction of serum.     

Sulfated cholecystokinin‐8 increases ghrelin secretion but does not affect oxyntomodulin in Holstein steers

The effect of appetite regulatory hormone cholecystokinin (CCK) on the secretions of oxyntomodulin (OXM) and ghrelin, and the effect of ghrelin on the secretions of CCK and OXM were studied in ruminants. Eight Holstein steers, 7 months old, 243 ± 7 kg body weight (BW), were arranged in an incomplete Latin square design (8 animals × 4 treatments × 4 days of sampling). Steers were intravenously injected with 10 µg of sulfated CCK‐8/kg BW, 20 µg of acyl ghrelin/kg BW, 100 µg of des‐acyl ghrelin/kg BW or vehicle. Blood samples were collected from ?60 min to 120 min relative to time of injection. Plasma concentrations of ghrelin, sulfated CCK and OXM were measured by double‐antibody radioimmunoassay. Plasma acyl ghrelin was increased to peak level (428.3 ± 6 pg/mL) at 60 min after injection of CCK compared with pre‐injected levels (203.3 ± 1 pg/mL). These results showed for the first time, that intravenous bolus injection of CCK increased ghrelin secretion in ruminants. In contrast, injection of ghrelin did not change CCK secretion. Administration of ghrelin or CCK has no effect on plasma OXM concentrations. In conclusion, our results show that administration of CCK increased ghrelin secretion but did not affect OXM release in ruminants. Ghrelin did not affect the secretions of CCK and OXM.     

Carbohydrates as Chemical Constituents of Biowaste Composts and their Humic and Fulvic Acids

The decomposition of organic matter of source-separated biowaste during composting was followed during 18 months. Compost samples were fractionated into three parts: (i) hot water soluble extract (HWE) (ii) bitumen fraction and (iii) humic substances (humic acids (HA) and fulvic acids (FA)). Original compost samples and the HA and FA fractions were hydrolyzed with sulfuric acid for hexoses and pentoses. Quantitative spectrophotometric and qualitative GC/MS analyses of monosaccharides as trimethylsilyl ethers of the corresponding alditols were carried out.

During composting, the amount of HA in the organic matter of the compost increased, the amounts of HWE and bitumen decreased and the amount of the FA fraction changed only a little. Carbohydrates were found to be important constituents of biowaste composts and their HA and FA fractions. Elemental analysis (C, N and H) of compost and HA samples showed an increase in the C:H ratio and in unsaturation of compounds during composting. The decrease in the C:N ratio was marginal.

The amounts of hexoses and pentoses in original compost samples and the HA and FA fractions decreased during composting. The sugar alcohols erythritol, xylitol, L-arabitol, ribitol, L-rhamnitol, L-fucitol, D-mannitol, D-glucitol and galactitol were identified in both the HA and FA fractions. 2-Deoxy-D-erythro-pentitol was identified in one HA fraction and inositol in two FA fractions. An analysis of gas chromatographic data for relative abundances showed that, in every sample except one and in every stage of composting D-glucitol was the main sugar alcohol. In general, the relative amount of D-glucitol decreased during composting, while the relative amounts of all other sugar alcohols increased.

As chemical indicators of compost maturity, carbohydrates would appear to be a important group of compounds. Most informative as a general indicator would be the ratio of the amount of HA to the amount of organic matter in the total compost samples.

According to our studies, the carbohydrates in composts are covalently bound to the structures of FA and HA. Carbohydrate determination clearly deserves more attention in the structural elucidation of FA and HA.     

Interaction of Late Season Foliar Spray of Urea and Fungicide Mixture in Wheat Production

Nitrogen (N) fertilization with foliar urea and fungicide treatment at flag leaf emergence (GS 47) are common strategies to improve both grain yield and quality in wheat ( Triticum aestivum L.). Mixing of urea and a fungicide, together, would save time in farm operations. In some cases, the effect of foliar sprayings of urea either alone or in combination with a fungicide may, however, give unexpected low response to grain yield and quality when compared to separate application of foliar urea and fungicide. This study was designated to provide more detailed information about the effects of late-season spraying of urea (15 kg N ha⁻¹ as an aqueous solution of 110 g l⁻¹) alone or mixed with fungicide (propiconazole, 125 g ha⁻¹) on the grain yield and grain protein content of spring wheat. To avoid foliar injury or phytotoxic effect of foliar spray of urea, mixing of urea with propiconazole in warm growing conditions should be avoided. In turn, during cool and rainy growing season, a mixture of these two chemicals is recommended in order to improve rapid absorbtion of both propiconazole and foliar urea. However, the genotypic differences were recorded in response to propiconazole and urea sprayings. The positive effects on cultivars of these chemicals were attributed to high leaf photosynthesis rate after propiconazole and foliar urea treatment and high leaf urease enzyme activity after foliar urea application.     

Bad nature: Newspaper representations of ecosystem disservices

Public perceptions and expectations towards ecosystems are an important part of environmental management and planning. This article focuses on the media representations that disseminate information, create framings and influence public attitudes. More specifically, the focus is on print media representations of ecosystem disservices. Ecosystem disservices are functions or properties of ecosystems that cause negative effects on human well-being or that are perceived as harmful, unpleasant or unwanted. Results from a case study focusing on the Finnish newspaper coverage of ecosystem disservices are presented. The results show that a wide variety of harms and nuisances related to ecosystems are brought up and discussed by the media. Implications for environmental management are discussed. The key claim is that taking into account the full repertoire of media representations of ecosystem functions is vital for preventing, anticipating and solving controversies related to environmental management and planning.     

Evaluation of refractive value by skiascopy in healthy Beagles

We examined the refractive value in healthy Beagles by skiascopy. The mean refractive value of 54 eyes of 27 Beagles was 0.08 ± 0.87 (mean ± SD) diopters (D). The numbers of eyes defined as having emmetropia, myopia and hyperopia were 34, 8 and 12, respectively. Anisometropia was detected in 4 dogs. The mean refractive values in the 3-6-year-old and 8-9-year-old groups were 0.26 ± 0.84 and -0.29 ± 0.82 D, respectively, with a significant difference between the two groups (P<0.05).     

Structural and chemical changes in pyrogenic organic matter aged in a boreal forest soil

biochar;charcoal;chronosequence;porosity;prescribed burning;soil amendment;X-ray microtomography