An Electronic Nose and Indicator Volatiles for Monitoring of the Composting Process

The aim of this research was to study whether electronic nose sensor technology (NST 3320, Applied Sensor, Sweden) can be used effectively for monitoring of the composting process. The effect of aeration on the composting process was examined using two aeration levels representing insufficient and optimal aeration for composting. An additional aim was to identify possible indicator gases in the volatile organic compound profiles of the composts by on-line FT-IR and gas chromatographic determinations. The results indicated that the electronic nose was able to distinguish between the two composter bins after 13 days of composting. Of the volatile metabolites that were identified, methyl ethyl ketone (MEK) proved to be a suitable indicator compound of anaerobicity as it was only produced in considerable quantities in the insufficiently aerated composter bin.     

Aeration improves the hygiene of cattle slurry and the quality of grass forage and silage†

The aeration of slurry at mesophilic temperature improves its hygiene, provided no fresh slurry is added to the tank during the 3–4 weeks of aeration. Microorganisms, such as Listeria monocytogenes, Yersinia enterocolitica and related species and coliphages, were reduced by 90–99.9%. However, the number of Clostridium was not affected. The typical odour of slurry diminished. The use of aerated slurry as fertilizer on growing grass may cause less risk of contamination either by enteric microorganisms or by butyric acid‐producing clostridia than the use of non‐aerated slurry. The hygiene level of grass was also sufficient when grown in a cold, rainy late summer and used for silage. None of the 62 samples of silage prepared from a second‐harvest grown in rainy conditions and fertilized with aerated slurry were found to have deteriorated. However, three samples out of 63 made during the same period but fertilized with non‐aerated slurry were observed to have deteriorated completely. Neither spreading method, band‐spreading or injection of the slurry into sward, had any effect on the microbiological hygiene of the samples.     

Die n-versorgung der getreidepflanzen im iosdv?-?tartu?-?pflanzenanalysen und n-bestimmung im boden

Der Internationale Organische Stickstoffdauerdüngungversuch (IOSDV) Tartu wurde 1989 mit den N-Stufen: 0-40-80-120-160 kg N/ha und den verschiedenen organischen Düngungsstufen: 400 dt/ha Rübenblatt, 40 dt/ha Stroh und 600 dt/ha Stallmist auf einer Fahlerde angelegt. Es wurden NH₄- und NO₃- N im Humushorizont des Bodens untersucht und der N-Gehalt im Aufwuchs von Sommerweizen und Sommergerste. Die mineralische und die mineralische-organische Düngung beeinflussten die Bestockung und Blüte der Getreidepflanzen. Die Getreidepflanzen waren während dieser Zeit ausreichend mit Stickstoff versorgt. Die gemessenen Werte stimmten mit den Angaben zur optimalen N-Versorgung in der Literatur überein (<citeref rid="b1">Bergmann, 1986</citeref>). Die N-Gehalte im Korn korrelierten positiv mit den Erträgen. Die N_min-Werte im Boden zeigten erwartungsgemäß im Herbst eine bessere Korrelation zum Ertrag von Sommergerste als die im Frühjahr gemessenen N_min-Werte. Sie wurden stärker durch den mineralisch gedüngten Stickstoff als durch die Nachwirkung der organischen Düngung beeinflusst. Die Ertrag von Sommerweizen war mehr durch die Witterungsbedingungen während der Vegetationszeit beeiflusst. The aim of the international organic-nitrogen long-term experiment (Internationaler organischer Stickstoffdauerdüngungsversuch (IOSDV), initiated in 1989) is to compare the effects of different forms of mineral nitrogen fertilizer (0-40-80-120-160 kg N/ha) with different organic amendments (beet leaves, 400 dt/ha; straw, 40 dt/ha; and FYM, 600 dt/ha) on loamy Podzoluvisol (FAO). The ion-exchangeable NH₄-nitrogen and NO₃-nitrogen content in humus layer and N-content in shoots of different stages of spring barley and spring wheat were studied. Mineral and organic fertilization influenced N-uptake at anthesis and tillering stage. Cereal plants had a sufficient supply of nitrogen at this time. Measured data are well in accordance with published results (Bergmann, 1986). Results of optimal N-content of shoots at different stages correlated positively and significantly with grain yields. N_min content in the humus layer in autumn was correlated better as in spring with grain yields of spring barley. In the vegetation period, N_min content correlates better with treatment with mineral nitrogen fertilizer than with use of organic amendments. In addition, yield of spring wheat is significantly correlated with weather conditions.     

Inter- and intra-annual variations in canopy fine litterfall and carbon and nitrogen inputs to the forest floor in two European coniferous forests

? Context

The amount and chemistry of litterfall have been known to strongly vary among the years with important implications for ecosystem nutrient cycles, but there are few quantitative data describing such variations.

? Aims

We studied the climatic implications on the variation in litterfall and its C and N input to soil in two distinct European coniferous forests.

? Methods

Year-to-year variations in canopy litterfall were measured in a Scots pine stand (Hyytiälä, Finland) over 13 years, and a Douglas fir stand (Speulderbos, The Netherlands) over 3 years.

? Results

Important inter-annual variations in litterfall were observed in Scots pine. Litterfall was mainly driven by leaf senescence; however, premature needle fall was observed in high wind speed and early frost events. The seasonal variation in litterfall was characterized by a maximum in September in Scots pine, and by a biphasic variation pattern in Douglas fir, in May and November. Lower seasonal variations and lower annual average in litterfall N content were observed in Scots pine.

? Conclusion

Significant inter- and intra-annual variations in litterfall and chemistry and between the sites were demonstrated; and it depended on year-to-year differences in climate and extreme weather events.     

Winter body mass and over-ocean flocking as components of danger management by Pacific dunlins

Background  

We compared records of the body mass and roosting behavior of Pacific dunlins (Calidris alpina pacifica) wintering on the Fraser River estuary in southwest British Columbia between the 1970s and the 1990s. 'Over-ocean flocking' is a relatively safe but energetically-expensive alternative to roosting during the high tide period. Fat stores offer protection against starvation, but are a liability in escape performance, and increase flight costs. Peregrine falcons (Falco peregrinus) were scarce on the Fraser River estuary in the 1970s, but their numbers have since recovered, and they prey heavily on dunlins. The increase has altered the balance between predation and starvation risks for dunlins, and thus how dunlins regulate roosting behavior and body mass to manage the danger. We therefore predicted an increase in the frequency of over-ocean flocking as well as a decrease in the amount of fat carried by dunlins over these decades.     

Analysis of technical lignins by two- and three-dimensional NMR spectroscopy

Modern multidimensional NMR spectroscopic methods were applied to investigate the effects of kraft pulping and oxygen delignification on lignin side-chain structures. In addition to the two-dimensional HSQC measurements, the three-dimensional HSQC-TOCSY technique was utilized to elucidate the (1)H-(1)H and (1)H-(13)C correlations of individual spin systems and thus indicate a certain lignin side-chain structure. Unlike earlier, nonlabeled samples were used for 3D measurements. According to 2D and 3D NMR spectra, most of the structures identified in milled wood lignin (MWL) are still present in technical lignins after kraft pulping and oxygen delignification. Although the main reaction during kraft pulping is the cleavage of beta-O-4 linkages, these structures are still left in spent liquor lignin as well as in residual lignin. The amount of coniferyl alcohol and dihydroconiferyl alcohol end groups, as well as some unidentified saturated end groups, is higher in technical lignins than in MWL. Contrary to our earlier observations, no diphenylmethane structures were observed in any technical lignins. Vinyl aryl ether structures could not be detected in technical lignins either.     

Feline intestinal parasites in Finland: prevalence, risk factors and anthelmintic treatment practices

The aim of this study was to estimate the prevalence of feline intestinal parasites in Finland and to determine the possible risk factors for infection. Altogether 411 feline fecal samples were analyzed with a flotation method to reveal helminth eggs and protozoan oocysts. Of the samples, 402 were also screened for Giardia species antigens with a commercial enzyme-linked immunosorbent assay kit. The cat owners completed a questionnaire. Toxocara cati prevalence was 5.4% and Toxascaris leonina 0.2%. Taenia species eggs were found in 1.5% of the samples and Isospora felis in 0.7%, whilst 3.2% of the samples tested positive for Giardia species antigen. Risk factors for Toxocara/Toxascaris species infection included being a non-pedigree cat, having access to the outdoors, living outside of the cities and receiving home-made food. Pedigree cats were at greater risk of contracting Giardia duodenalis. The majority of the cat owners (62.4%) treated their cat with anthelmintics 2-4 times per year.     

A microcosmos study on the effects of cd-containing wood ash on the coniferous humus fungal community and the cd bioavailability

Background and Aims

The use of wood ash in forestry has been questioned because the cadmium (Cd) concentration of ash, which varies between 1 and 20 mg kg^-1 ash, exceeds the level allowed for fertilizers (3 mg kg^-1) used in agriculture. To investigate the effects of Cd and ash on the fungal community composition and Cd bioavailability of the humus layer of boreal, coniferous forests, pumice or wood ash, spiked with a water soluble (CdCl₂) or insoluble (CdO) form of Cd at three levels (0, 400 and 1000 mg kg^-1), were applied at a fertilization level of 5000 kg ha^-1 in a laboratory microcosm study.

Methods

After 2 months, the humus in the microcosms was sampled and extracted for total DNA to detect changes in the fungal community by using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. PCR was performed using the fungal 18S rDNA primers FR1 + FF390 and FR1 + NS1. The bioavailability of Cd was measured with a bacterial biosensor(Bacillus subtilis BR 151/pT0024) emitting light in the presence of Cd.

Results

Using the primer pairs FR1 + FF390 and FR1 + NS1, resulted in over 35 and 15 DGGE bands, respectively. Both primer pairs detected an ash, but no Cd effect. When using FR1 + FF390, a higher fluorescence was observed in one DGGE band of all ashed samples compared to the pumiced samples. With the primer pair FR1 + NS1, the ashed samples had a DGGE band which was not visible or only faintly visible in the pumiced samples. In addition, one DGGE band disappeared from the ashed samples. Humus layer water extracts showed that the Cd added with the pumice was in a bioavailable form. The luminescence intensity of the biosensor was dependent on the form and level of the Cd added. No luminescence was detected when the Cd was added with the ash.

Conclusions

Ash fertilization altered the humus layer fungal community, whereas the level and form of additional Cd in the ash had no influence because it was not bioavailable.     

Lingonberry (Vaccinium vitis-idaea) and European cranberry (Vaccinium microcarpon) proanthocyanidins: isolation, identification, and bioactivities

European, small-fruited cranberries (Vaccinium microcarpon) and lingonberries (Vaccinium vitis-idaea) were characterized for their phenolic compounds and tested for antioxidant, antimicrobial, antiadhesive, and antiinflammatory effects. The main phenolic compounds in both lingonberries and cranberries were proanthocyanidins comprising 63-71% of the total phenolic content, but anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and flavonols were also found. Proanthocyanidins are polymeric phenolic compounds consisting mainly of catechin, epicatechin, gallocatechin, and epigallocatechin units. In the present study, proanthocyanidins were divided into three groups: dimers and trimers, oligomers (mDP 4-10), and polymers (mDP > 10). Catechin, epicatechin, A-type dimers and trimers were found to be the terminal units of isolated proanthocyanidin fractions. Inhibitions of lipid oxidation in liposomes were over 70% and in emulsions over 85%, and in most cases the oligomeric or polymeric fraction was the most effective. Polymeric proanthocyanidin extracts of lingonberries and cranberries were strongly antimicrobial against Staphylococcus aureus, whereas they had no effect on other bacterial strains such as Salmonella enterica sv. Typhimurium, Lactobacillus rhamnosus and Escherichia coli. Polymeric fraction of cranberries and oligomeric fractions of both lingonberries and cranberries showed an inhibitory effect on hemagglutination of E. coli, which expresses the M hemagglutin. Cranberry phenolic extract inhibited LPS-induced NO production in a dose-dependent manner, but it had no major effect on iNOS of COX-2 expression. At a concentration of 100 μg/mL cranberry phenolic extract inhibited LPS-induced IL-6, IL-1β and TNF-α production. Lingonberry phenolics had no significant effect on IL-1β production but inhibited IL-6 and TNF-α production at a concentration of 100 μg/mL similarly to cranberry phenolic extract. In conclusion the phenolics, notably proanthocyanidins (oligomers and polymers), in both lingonberries and cranberries exert multiple bioactivities that may be exploited in food development.