Near‐infrared spectroscopy can predict the composition of organic matter in soil and litter     

Thomas Terhoeven‐Urselmans  Kerstin Michel  Mirjam Helfrich  Heiner Flessa  Bernard Ludwig 《植物养料与土壤学杂志》2006,169(2):168-174

The usefulness and limitations of near‐infrared reflectance spectroscopy (NIRS) for the assessment of several soil characteristics are still not sufficiently explored. The objective of this study was to evaluate the ability of visible and near‐infrared reflectance (VIS‐NIR) spectroscopy to predict the composition of organic matter in soils and litter. Reflectance spectra of the VIS‐NIR region (400–2500 nm) were recorded for 56 soil and litter samples from agricultural and forest sites. Spectra were used to predict general and biological characteristics of the samples as well as the C composition which was measured by ¹³C‐CPMAS‐NMR spectroscopy. A modified partial least‐square method and cross‐validation were used to develop equations for the different constituents over the whole spectrum (1st to 3rd derivation). Near‐infrared spectroscopy predicted well the C : N ratios, the percentages of O‐alkyl C and alkyl C, the ratio of alkyl C to O‐alkyl C, and the sum of phenolic oxidation products: the ratios of standard deviation of the laboratory results to standard error of cross‐validation (RSC) were greater than 2, the regression coefficients (a) of a linear regression (measured against predicted values) ranged from 0.9 to 1.1, and the correlation coefficients (r) were greater than 0.9. Satisfactorily (0.8 ≤ a ≤ 1.2, r ≥ 0.8, and 1.4 ≤ RSC ≤ 2.0) assessed were the contents of C, N, and production of DOC, the percentages of carbonyl C and aromatic C and the ratio of alkyl C to aromatic C. However, the N‐mineralization rate and the microbial biomass were predicted unsatisfactorily (RSC < 1.4). The good and satisfactory predictions reported above indicate a marked usefulness of NIRS in the assessment of biological and chemical characteristics of soils and litter.  相似文献   

Stable isotope N and C labelling of different functional groups of earthworms and their casts: A tool for studying trophic links     

Barbara Heiner  Thomas Frank  Johann G. Zaller 《Pedobiologia》2011,54(3):169-175

Earthworms (Oligochaeta: Lumbricidae) have substantial effects on the structure and fertility of soils with consequences for the diversity of plant communities and associated ecosystem functions. However, we still lack a clear understanding of the functional role earthworms play in terrestrial ecosystems, partly because easy-to-use methods to quantify their activities are missing. In this study, we tested whether earthworms and their casts can be dual-labelled with ¹⁵N and ¹³C stable isotopes by cultivating them in soil substrate amended with ¹⁵N ammonium nitrate and ¹³C-glucose. Additionally, we also wanted to know whether (i) earthworms from different functional groups (soil-feeders vs. litter-feeders) and their casts would differ in their incorporation of stable isotopes, (ii) if enrichment levels are higher if the same amount of isotopes is applied in one dose or in staggered doses, and (iii) if isotopic enrichment in casts changes when they are stored in a conditioning cabinet or in a pot filled with soil placed in a greenhouse. Our findings show the feasibility of dual-labelling tissues and casts of both litter-feeding (Lumbricus terrestris) and soil-feeding (Aporrectodea caliginosa) earthworms using the same method. The advantage of this method is that earthworms and their casts can be labelled under realistic conditions by cultivating them for only four days in soil that received a one-time addition of commercially available stable isotopes instead of offering labelled plant material. In earthworms, the isotopic enrichment remained at a stable level for at least 21 days; labelled casts could be stored for at least 105 days without significantly decreasing their isotopic signals. This simple and efficient method opens new avenues for studying the role of these important ecosystem engineers in nutrient cycling and their functional relationships with other organisms.  相似文献   

Ammonia and Nitrous Oxide Emissions after Landspreading of Slurry as Influenced by Application Technique and Dry Matter-Reduction. II. Short Term Nitrous Oxide Emissions     

Joachim Clemens  Robert Vandr  Martin Kaupenjohann  Heiner Goldbach 《植物养料与土壤学杂志》1997,160(4):491-496

Strategies reducing NH₃ volatilisation from slurry include separation of slurry, special application techniques and additives. We studied the impact of manure separation and application technique on N₂O release after manure application. Untreated and separated cattle slurry (dry matter content of 7.1% and 4.4%, respectively) was applied to winter wheat using broadcast and banded application and injection. The N₂O emissions were measured at high frequency for 14 to 20 days after slurry treatment by the closed chamber method. Manured plots showed significantly higher N₂O emissions than the control plots but neither dry matter reduction of slurry nor application technique significantly influenced the N₂O emissions. The variability of N₂O emission was influenced by the application technique and increased in the order: banded application – injection – broadcast application. There was no correlation between NH₃ losses from applied slurry and N₂O emissions. Thus reducing ammonia volatilisation will not necessarily increase N₂O emissions.  相似文献   

The influence of nitrate and ammonium fertilization on N2O release and CH4 uptake of a well-drained topsoil demonstrated by a soil microcosm experiment     

Heiner Flessa  Wolfgang Pfau  Peter Drsch  Friedrich Beese 《植物养料与土壤学杂志》1996,159(5):499-503

The effects of the application of KNO₃ and NH₄Cl (100 kg N ha^?1) on N₂O release and CH₄ uptake by a well-aerated topsoil (porosity: 55%, water-filled pore space: 67% of the total pore space) were studied in a laboratory incubation experiment over 50 days using a soil microcosm system with an automated registration of N₂O and CH₄ fluxes. The total N₂O-N losses over 50 days were low for all treatments and amounted to 0.9 mg m^?2 for the control, 1.2 mg m^?2 for the soil columns fertilized with KNO3, and 7.3 mg m^?2 for the soil columns fertilized with NH₄Cl. The slightly elevated N₂O release after the application Of NH₄Cl was associated with the nitrification of NH₄⁺ added. Only ?0.06% of the fertilized NH₄?N was lost as N₂O. This nitrogen fertilization reduced the CH₄ uptake of the soil columns by 43% (NH₄Cl) and 21% (KNO₃), respectively.  相似文献   

Numerical modeling of water balance for temporary landfill cover in North Germany          下载免费PDF全文

Marcin K. Widomski  Steffen Beck Broichsitter  Alexander Zink  Heiner Fleige  Rainer Horn  Witold Stępniewski 《植物养料与土壤学杂志》2015,178(3):401-412

At the end of waste disposal in 2005, a temporary mineral system was constructed to cover the waste body of the municipal landfill in Rastorf (N Germany). The aim of this study was to evaluate the effectiveness of this temporary cover system in limiting the infiltration of surface water into the waste body. The numerical modeling for the hydrological year 2012 was performed in FEFLOW 6.0. The required input data for modeling were achieved by laboratory measurements of the saturated hydraulic conductivity and the water retention characteristics of the mineral layers. The assumed initial and boundary conditions were based on in‐situ measurements of matrix potential and volumetric water content at three different measuring points by tensiometers, FDR sensors and observed meteorological conditions. The model was applied according to Darcy's and Richards' equations for variably saturated flow. Our results allowed assessing the components of water balance for a temporary cover system, especially water seepage into the waste body. The correlation between the measured and modeled volumetric soil water content in the layered temporary cover system was observed (R² = 0.56 to 0.90). Deviations between the measured and modeled values are superficially related to the soil´s heterogeneity. In conclusion, the measured and modeled water balance parameters indicate that the temporary coverage system remains effective in limiting the infiltration rate. However, our studies revealed that the calculated and measured water seepage exceeded the values allowable by the German regulations. Additional studies have to assess variations in the soil water characteristics caused by weather‐related wetting and drying cycles and influence of waste settlement changing the profile of slope.  相似文献   

Clinical Effects and Antivenom Use for Snake Bite Victims Treated at Three US Hospitals in Afghanistan     

Jason D. Heiner  Vikhyat S. Bebarta  Shawn M. Varney  Jason D. Bothwell  Aaron J. Cronin 《The Forestry Chronicle》2013,24(4):412-416

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Cross-sectional study on acrylamide hemoglobin adducts in subpopulations from the European Prospective Investigation into Cancer and Nutrition (EPIC) Study     

Vesper HW  Slimani N  Hallmans G  Tjønneland A  Agudo A  Benetou V  Bingham S  Boeing H  Boutron-Ruault MC  Bueno-de-Mesquita HB  Chirlaque D  Clavel-Chapelon F  Crowe F  Drogan D  Ferrari P  Johansson I  Kaaks R  Linseisen J  Lund E  Manjer J  Mattiello A  Palli D  Peeters PH  Rinaldi S  Skeie G  Trichopoulou A  Vineis P  Wirfält E  Overvad K  Strömberg U 《Journal of agricultural and food chemistry》2008,56(15):6046-6053

Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered.  相似文献   

Groundwater level controls CO2, N2O and CH4 fluxes of three different hydromorphic soil types of a temperate forest ecosystem     

Hermann F. Jungkunst  Heiner Flessa  Christoph Scherber  Sabine Fiedler 《Soil biology & biochemistry》2008,40(8):2047-2054

Hydromorphic soils should exhibit higher climate change feedback potentials than well aerated soils since soil organic matter (SOM) losses in them are predicted to be much larger than those of well aerated soils. To evaluate a combined feedback relationship between groundwater level (GWL) and total greenhouse gas (GHG) emission, a greenhouse microcosm experiment was performed by exposing three hydromorphic forest soil types that differed in carbon content to three water levels (?40, ?20 and ?5 cm) while plants were excluded. Net GHG fluxes were measured continuously. GHG concentrations plus oxygen were measured in soil air and soil water at different depths. In this study, soil type hardly affected GHG emissions but GWL did. CO₂ emissions peaked at GWL of ?40 cm and declined on average to 65 and 33% during GWL at ?20 and ?5 cm, respectively. CH₄ emissions showed the opposite pattern having the highest emission rates at GWL of ?5 cm and compared to that on average only ?3 and ?8% during GWL at ?20 and ?40 cm, respectively. The highest mean N₂O emissions were detected at the intermediate GWL of ?20 cm, whereas it is reduced on average to 18% for GWL at ?40 cm and at ?5 cm. The highest greenhouse gas emissions (in CO₂ equivalents) were calculated for GWL at ?20 cm. During GWL at ?40 cm, CO₂ equivalent fluxes were only insignificantly lower. CO₂ equivalent fluxes reduced explicitly in mean to 35% with GWL at ?5 cm. The outcome emphasizes that anaerobic SOM decomposition apparently produces a lower warming potential than aerobic SOM decomposition. Undoubtedly, hydromorphic soils have to be considered for climate–carbon feedback scenarios.  相似文献   

Formation and use of microbial residues after adding sugarcane sucrose to a heated soil devoid of soil organic matter     

Brigitte Engelking  Heiner Flessa  Rainer Georg Joergensen 《Soil biology & biochemistry》2008,40(1):97-105

A 67-day incubation experiment was carried out with a soil initially devoid of any organic matter due to heating, which was amended with sugarcane sucrose (C₄-sucrose with a δ¹³C value of ?10.5‰), inorganic N and an inoculum for recolonisation and subsequently at day 33 with C₃-cellulose (δ¹³C value of ?23.4‰). In this soil, all organic matter is in the microbial biomass or in freshly formed residues, which makes it possible to analyse more clearly the role of microbial residues for decomposition of N-poor substrates. The average δ¹³C value over the whole incubation period was ?10.7‰ in soil total C in the treatments without C₃-cellulose addition. In the CO₂ evolved, the δ¹³C values decreased from ?13.4‰ to ?15.4‰ during incubation. In the microbial biomass, the δ¹³C values increased from ?11.5‰ to ?10.1‰ at days 33 and 38. At day 67, 36% of the C₄-sucrose was left in the treatment without a second amendment. The addition of C₃-cellulose resulted in a further 7% decrease, but 4% of the C₃-cellulose was lost during the second incubation period. Total microbial biomass C declined from 200 μg g^?1 soil at day 5 to 70 μg g^?1 soil at day 67. Fungal ergosterol increased to 1.5 μg g^?1 soil at day 12 and declined more or less linearly to 0.4 μg g^?1 soil at day 67. Bacterial muramic acid declined from a maximum of 35 μg g^?1 soil at day 5 to a constant level of around 16 μg g^?1 soil. Glucosamine showed a peak value at day 12. Galactosamine remained constant throughout the incubation. The fungal C/bacterial C ratio increased more or less linearly from 0.38 at day 5 to 1.1 at day 67 indicating a shift in the microbial community from bacteria to fungi during the incubation. The addition of C₃-cellulose led to a small increase in C₃-derived microbial biomass C, but to a strong increase in C₄-derived microbial biomass C. At days 45 and 67, the addition of N-free C₃-cellulose significantly decreased the C/N ratio of the microbial residues, suggesting that this fraction did not serve as an N-source, but as an energy source.  相似文献   

Simulating the spread of classical swine fever virus between a hypothetical wild-boar population and domestic pig herds in Denmark   总被引：1，自引：1，他引：0  

Boklund A  Goldbach SG  Uttenthal A  Alban L 《Preventive veterinary medicine》2008,85(3-4):187-206

Denmark has no free-range wild-boar population. However, Danish wildlife organizations have suggested that wild boar should be reintroduced into the wild to broaden national biodiversity. Danish pig farmers fear that this would lead to a higher risk of introduction of classical swine fever virus (CSFV), which could have enormous consequences in terms of loss of pork exports. We conducted a risk assessment to address the additional risk of introducing and spreading CSFV due to the reintroduction of wild boar. In this paper, we present the part of the risk assessment that deals with the spread of CSFV between the hypothetical wild-boar population and the domestic population. Furthermore, the economic impact is assessed taking the perspective of the Danish national budget and the Danish pig industry. We used InterSpreadPlus to model the differential classical swine fever (CSF) risk due to wild boar. Nine scenarios were run to elucidate the effect of: (a) presence of wild boar (yes/no), (b) locations for the index case (domestic pig herd/wild-boar group), (c) type of control strategy for wild boar (hunting/vaccination) and (d) presence of free-range domestic pigs. The presence of free-range wild boar was simulated in two large forests using data from wildlife studies and Danish habitat data. For each scenario, we estimated (1) the control costs borne by the veterinary authorities, (2) the control-related costs to farmers and (3) the loss of exports associated with an epidemic. Our simulations predict that CSFV will be transmitted from the domestic pig population to wild boar if the infected domestic pig herd is located close to an area with wild boar (<5 km). If an outbreak begins in the wild-boar population, the epidemic will last longer and will occasionally lead to several epidemics because of periodic transfer of virus from groups of infected wild boar to domestic pig herds. The size and duration of the epidemic will be reduced if there are no free-range domestic pig herds in the area with CSF-infected wild boar. The economic calculations showed that the total national costs for Denmark (i.e. the direct costs to the national budget and the costs to the pig industry) related to an outbreak of CSF in Denmark will be highly driven by the reactions of the export markets and in particular of the non-EU markets. Unfortunately, there is a substantial amount of uncertainty surrounding this issue. If hunting is used as a control measure, the average expenses related to a CSF outbreak will be 40% higher if wild boar are present compared with not present. However, a vaccination strategy for wild boar will double the total costs compared with a hunting strategy.  相似文献