Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Database
Language
Publication year range
1.
Mycologia ; 116(1): 44-58, 2024.
Article in English | MEDLINE | ID: mdl-37955984

ABSTRACT

Over the decades our understanding of lichens has shifted to the fact that they are multiorganismic, symbiotic microecosystems, with their complex interactions coming to the fore due to recent advances in microbiomics. Here, we present a mutualistic-parasitic continuum dynamics scenario between an orange lichen and a lichenicolous fungus from the Atacama Desert leading to the decay of the lichen's photobiont and leaving behind a black lichen thallus. Based on isolation, sequencing, and ecophysiological approaches including metabolic screenings of the symbionts, we depict consequences upon infection with the lichenicolous fungus. This spans from a loss of the lichen's photosynthetic activity and an increased roughness of its surface to an inhibition of the parietin synthesis as a shared pathway between the photobiont and the mycobiont, including a shift of secondary metabolism products. This degree of relations has rarely been documented before, although lichenicolous fungi have been studied for over 200 years, adding an additional level to the view of interactions within lichens.


Subject(s)
Chlorophyta , Lichens , Lichens/microbiology , Phylogeny , Fungi , Symbiosis
2.
Article in English | MEDLINE | ID: mdl-26305901

ABSTRACT

The addition of wood chips as a co-substrate can promote the degradation of oil in soil. Therefore, in the present study, the tree species-specific impact of wood chips of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L.) and Western balsam poplar (Populus trichocarpa L.) on the degradation of crude oil was tested in beach sand in a 4-week incubation experiment. The CO2-C release increased in the order of control without wood chips < +spruce < +pine < +poplar. Initial and final hydrocarbon concentrations (C10 to C40), as indicators for the oil degradation, were determined with gas chromatography-flame ionization detection (GC-FID). The degradation increased for the light fraction (C10 to C22), the heavy fraction (C23 to C40) as well as the whole range (C10 to C40) in the order of control without wood chips (f(degrad.) = 23% vs. 0% vs. 12%) < +poplar (f(degrad.) = 49% vs. 19% vs. 36%) < +spruce (f(degrad.) = 55% vs. 34% vs. 46%) < +pine (f(degrad.) = 60% vs. 44% vs. 53%), whereas the heavy fraction was less degraded in comparison to the light fraction. It can be concluded, that the tree species-specific wood quality is a significant control of the impact on the degradation of hydrocarbons, and pine wood chips might be promising, possibly caused by their lower decomposability and lower substrate replacement than the other wood species.


Subject(s)
Petroleum/metabolism , Trees/classification , Wood/chemistry , Carbon/analysis , Hydrocarbons/analysis , Nitrogen/analysis , Picea/metabolism , Pinus sylvestris/metabolism , Soil/chemistry , Sulfur/analysis
3.
J Environ Qual ; 42(1): 199-207, 2013.
Article in English | MEDLINE | ID: mdl-23673755

ABSTRACT

Hydrochars, technically manufactured by hydrothermal carbonization (HTC) of biomass residues, are recently tested in high numbers for their suitability as feedstock for bioenergy production, the bioproduct industry, and as long-term carbon storage in soil, but ecological effects in the soil-plant system are not sufficiently known. Therefore, we investigated the influence of different biomass residues and process duration on the molecular composition of hydrochars, and how hydrochar addition to soils affected the germination of spring barley ( L.) seeds. Samples from biomass residues and the corresponding hydrochars were analyzed by pyrolysis-field ionization mass spectrometry (Py-FIMS) and gaseous emissions from the germination experiments with different soil-hydrochar mixtures by gas chromatography/mass spectrometry (GC/MS). The molecular-level characterization of various hydrochars by Py-FIMS clearly showed that the kind of biomass residue influenced the chemical composition of the corresponding hydrochars more strongly than the process duration. In addition to various detected possible toxic substances, two independent mass spectrometric methods (Py-FIMS and GC/MS) indicated long C-chain aliphatic compounds which are typically degraded to the C-unit ethylene that can evoke phytotoxic effects in high concentrations. This showed for the first time possible chemical compounds to explain toxic effects of hydrochars on plant growth. It is concluded that the HTC process did not result in a consistent product with defined chemical composition. Furthermore, possible toxic effects urgently need to be investigated for each individual hydrochar to assess effects on the soil organic matter composition and the soil biota before hydrochar applications as an amendment on agricultural soils.


Subject(s)
Carbon , Soil , Biomass , Carbon/chemistry , Charcoal/chemistry , Mass Spectrometry , Soil/chemistry , Soil Pollutants/chemistry
4.
Chemosphere ; 79(7): 745-53, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20347116

ABSTRACT

The long-time use of persistent organic pollutants (POPs) led to a world-wide contamination of environmental compartments. Although, bans of numerous POPs reduced the POP input to rivers. Floodplain soils are still highly contaminated, because they are sinks for these compounds, which restrict their agricultural use. Hence, the intention of this study was the determination of 29 relevant POPs in two soil depths (0-10 cm and 10-20 cm) of a field experiment to get a survey on the small-scale spatial variability of the experimental site and to establish a baseline for phytoremediation experiments. The POP concentrations ranged from 0.1 microg kg(-1) to 160 microg kg(-1) and showed an increase of dieldrin, endrin, endosulfan I, endosulfan II, heptachlor, p,p'-DDE, o,p'-DDE and methoxychlor concentrations on average in the river Elbe floodplains between the years 1998 and 2007. However, there was a pronounced small-scale spatial variability of POP concentrations in vertical and horizontal direction. The latter was estimated by comparing the relative standard deviations (RSDs) of the POP concentrations in sample sets located at sites of increasing distance from <1m to >10000 m.


Subject(s)
Hydrocarbons, Chlorinated/chemistry , Soil Pollutants/chemistry , Soil/analysis , Dichlorodiphenyl Dichloroethylene/analysis , Dichlorodiphenyl Dichloroethylene/chemistry , Environmental Monitoring , Germany , Hexachlorobenzene/analysis , Hexachlorobenzene/chemistry , Hexachlorocyclohexane/analysis , Hexachlorocyclohexane/chemistry , Hydrocarbons, Chlorinated/analysis , Polychlorinated Biphenyls/analysis , Polychlorinated Biphenyls/chemistry , Rivers , Soil Pollutants/analysis
5.
J Environ Sci Health B ; 43(1): 81-95, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18161578

ABSTRACT

Fast pyrolysis of chicken manure produced the following three fractions: bio-oil Fraction I, bio-oil Fraction II, and a char. In a previous investigation we analyzed each of the four materials by curie-point pyrolysis-gas chromatography/mass spectrometry (CpPy-FDMS). The objective of this article is to report on the analyses of the same chicken manure and the three fractions derived from it by fast pyrolysis. We now used pyrolysis-field ionization mass spectrometry (Py-FIMS) to characterize the three fractions. In addition, the two bio-oil materials were analyzed by pyrolysis-field desorption mass spectrometry (Py-FDMS). The use of both Py-FIMS and Py-FDMS produced signals over significantly wider mass ranges than did CpPy-GC/MS, and so allowed us to identify considerably larger numbers of constituents in each material. Individual compounds identified in the mass spectra were classified into the following twelve compound classes: (a) low molecular weight compounds (< m/z 62); (b) carbohydrates; (c) phenols + lignin monomers; (d) lignin dimers; (e) n-alkylbenzenes; (f) N-heterocyclics; (g) n-fatty acids; (h) n-alkanes; (i) alkenes; (j) sterols; (k) n-diols and (l) high molecular weight compounds (> m/z 562). Of special interest were the high abundances of low-molecular weight compounds in the two bio-oils which constituted close to one half of the two bio-oils. Prominent among these compounds were water, ammonia, acetic acid, acetamide, propyl radical, formamide and hydrogen cyanide. The main quantitative differences between the two bio-oils was that bio-oil Fraction I, as analyzed by the two mass spectrometric methods, contained lower concentrations of low-molecular weight compounds, carbohydrates, and N-heterocyclics than bio-oil Fraction II but was richer in lignin dimers, n-alkylbenzenes and aliphatics (n-fatty acids, n-alkanes, alkenes, and n-diols). Of special interest were the N-heterocyclics in the two bio-oils such as pyrazole, pyrazoline, substituted pyrroles, pyridine and substituted pyridines, substituted methoxazole, substituted pyrazines, indole and substituted indoles. Fatty acids in all four materials ranged from n-C(9) to n-C(33), alkanes from n-C(9) to n-C(40), alkenes from C(10:1) to C(40:1) and diols from n-C(7) to n-C(29). The chicken manure, bio-oil Fraction I, and char each contained about 4% sterols with cholesterol, ethylcholestriene, ergosterol, ethylcholestene, ethylcholesterol and beta -sitosterol as major components. Semi-quantitative estimates of the total materials identified by Py-FIMS were: chicken manure: 61.1%; bio-oil Fraction I: 81.3%; bio-oil Fraction II: 78.6%; char: 61.3%; and by Py-FDMS were: bio-oil Fraction I: 65.4%; bio-oil Fraction II: 70.0%.


Subject(s)
Environmental Pollutants/analysis , Hot Temperature , Manure/analysis , Mass Spectrometry/methods , Oils/analysis , Oils/chemistry , Adsorption , Animals , Chickens , Molecular Weight , Oxidation-Reduction , Volatilization
6.
J Environ Sci Health B ; 42(1): 79-95, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17162571

ABSTRACT

The initial chicken manure and the three fractions derived from it by fast pyrolysis, that is, the two biooils Fractions I and II as well as the residual char were analyzed by Curie-point pyrolysis-gas chromatography/mass spectrometry (Cp Py-GC/MS). The individual compounds identified were grouped into the following six compound classes: (a) N-heterocyclics; (b) substituted furans; (c) phenol and substituted phenols; (d) benzene and substituted benzenes; (e) carbocyclics; and (f) aliphatics. Of special interest were the relatively high concentrations of N-heterocyclics in biooil Fraction II which was obtained in the highest yield and had the highest calorific value. Prominent N-heterocyclics in biooil Fraction II were methyl-and ethyl-substituted pyrroles, pyridines, pyrimidine, pyrazines, and pteridine. Also noteworthy was the high abundance of aliphatics in biooil Fraction I and the char. The alkanes and alkenes in biooil Fraction I ranged from n-C7 to n-C18 and C7:1 to C18:1, respectively, and those in the char from n-C7 to n-C19 and C7:1 to C19:1, respectively. The N-heterocyclics in the two biooil Fractions came from the chicken manure, from proteinaceous materials during fast pyrolysis or were formed during the fast pyrolysis manure conversion by the Maillard reaction which involved the formation of N-heterocyclics by amino acids interacting with sugars.


Subject(s)
Environmental Pollutants/analysis , Gas Chromatography-Mass Spectrometry/methods , Hot Temperature , Manure/analysis , Oils/analysis , Oils/chemistry , Animals , Carbon Isotopes , Chickens , Environmental Pollutants/chemistry , Oxidation-Reduction , Volatilization
7.
Biodegradation ; 17(5): 473-85, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16477355

ABSTRACT

Biodegradation of organic matter is required to reduce the potential of municipal solid waste for producing gaseous emissions and leaching contaminants. Therefore, we studied leachates of an aerobic-treated waste from municipal solids and a sewage sludge mixture that were re-circulated to decrease the concentration of biodegradable organic matter in laboratory-scale reactors. After 12 months, the total organic C and biological and chemical oxygen demands were reduced, indicating the biodegradation of organic compounds in the leachates. Curie-point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and pyrolysis-field ionization mass spectrometry (Py-FIMS) revealed that phenols, alkylaromatic compounds, N-containing compounds and carbohydrates were the predominate compounds in the leachates and solid waste. Leachate re-circulation led to a higher thermal stability of the residual organic matter as indicated by temperature-resolved Py-FIMS. Admixture of sewage sludge to solid waste was less effective in removing organic compounds from the leachates. It resulted in drastic higher and more bio-resistant loads of organic matter in the leachates and revealed increased proportions of alkylaromatic compounds. The biodegradation of organic matter in leachates, re-circulated through municipal solid waste, offers the potential for improved aerobic waste treatments and should be investigated on a larger scale.


Subject(s)
Bioreactors , Organic Chemicals/analysis , Refuse Disposal/methods , Sewage/chemistry , Water Pollutants, Chemical/chemistry , Aerobiosis , Biodegradation, Environmental , Carbon/analysis , Gas Chromatography-Mass Spectrometry , Oxygen/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL