Nitrogen availability decreases prokaryotic diversity in sandy soils     

Silke Ruppel  Vigdis Torsvik  Frida Lise Daae  Lise Øvreås  Jörg Rühlmann 《Biology and Fertility of Soils》2007,43(4):449-459

In this study, the interrelation between nitrogen availability and prokaryotic diversity are studied using a well-characterised system from a long-term field experiment on a loamy sandy soil. The prokaryotic potential functional diversity and community composition were assessed using community-level physiological profiling (CLPP), and their phylogenetic diversity was analysed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) in combination with sequencing analysis. Highest prokaryotic potential functional diversity was measured in the control soil receiving no N fertilisation, indicating an efficient as well as versatile utilisation of the substrates in this soil. Both substrate utilisation richness and substrate utilisation evenness, the two constituents of the functional diversity, were decreased with increasing N supply. Furthermore, distinct prokaryotic community compositions were generated in N-enriched soils compared to unfertilised control soils. These differences suggest a dominance of populations adapted to utilising readily available substrates. We demonstrated that the shift in prokaryotic functional diversity was connected to a shift in the phylogenetic structure of the bacterial and archaeal communities. Taken together, our data clearly show that, for the sandy soil system, prokaryotic diversity and N availability were interrelated.  相似文献   

A century of teaching soil science at Moscow State University (1906–2006)     

G. V. Dobrovol’skii 《Eurasian Soil Science》2007,40(8):907-909

  相似文献   

Changes in the solid and liquid phases of different soils in model experiments with monoliths     

I. M. Gadzhiev  M. I. Dergacheva 《Eurasian Soil Science》2007,40(8):814-820

In long-term (20-year-long) experiments, the behavior of different soils under natural conditions different from their usual functioning conditions were analyzed. From soils under natural conditions, organic and mineral substances were partly leached or accumulated under the influence of introduced mixed fir, cedar, and birch falloff. During the time of the experiment, the humus composition distinctly changed. The leached chernozem turned out to be the most stable object; the loamy rock was the least stable one. In the latter, humus was notably accumulated. The intensity of the substance flux through the soils already began to change in 3–5 years, but only after 15 years did some quantitative changes take place. At the same time, the trends of the changes depended on the genesis and initial properties of the soils. The composition of the organic substances in the lysimetric water was related to the soil nature, and, during 20 years, it essentially did not change.  相似文献   

Tracing Pharmaceuticals in the Unsaturated Zone (10 pp)     

Traugott J. Scheytt  Petra Mersmann  Elzbieta Rejman-Rasinski  Anja These 《Journal of Soils and Sediments》2007,7(2):75-84

Background, Aim and Scope   One of the first occurrences of pharmaceutically active compounds in groundwater was reported from the sewage irrigation farms south of Berlin. At these sewage irrigation farms treated sewage effluent passed the soil and unsaturated zone before reaching the aquifer. Clofibric acid was detected in pore water from soils of those sewage irrigation farms in concentrations between 65 ng/L and 1430 ng/L. The aim of this study was to investigate the transport behavior of regularly detected clofibric acid, diclofenac, ibuprofen, and propyphenazone under conditions comparable to those at the sewage irrigation farms in a multiple compound sand column laboratory experiment. Materials and Methods   Sediment column experiments were conducted to study the transport of pharmaceuticals in the unsaturated zone. The migration was measured in fine to medium grained sand and leaching solution containing 1 mg/L of pharmaceutically active compounds and 61 mg/L of the tracer lithium chloride (LiCl). For the analysis of the pharmaceutical compounds the water samples were adjusted to a pH value of 2 and then extracted by solid-phase extraction (SPE). Before extraction, the samples were spiked with a surrogate standard for analytical quality control. The sample extracts were analyzed by capillary gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM). Depending on the sample volume (100 to 200 mL) and the matrix, the limits of detection were between 1 and 10 ng/L, and the limits of quantitation were between 5 and 25 ng/L. Analysis for calcium, magnesium and lithium were carried out using a 'Trace Scan' ICP-AES from Thermo Jarrel Ash. Sodium, potassium, iron and manganese were analyzed using a Philips PU 9400 flame AAS. Analysis of anions was performed on a Dionex ion chromatograph DX 120. Results   At the sewage irrigation farms the average concentrations of clofibric acid in the unsaturated zone declined from higher values near ground surface (480 ng/L) to lower values near the groundwater table (65 ng/L). From the pharmaceuticals analyzed only clofibric acid, primidone and propyphenazone could be analyzed in the first (upper) aquifer at the sewage irrigation farms. All other pharmaceuticals could neither be detected in the first aquifer nor in the deeper aquifers. Breakthrough curves from soil column experiments revealed no transformation and no retardation for clofibric acid, whereas transformation of diclofenac was so high (79%) that no retardation factor could be calculated. Ibuprofen was significantly transformed (37%), transformation of propyphenazone (17%) was quite low and retardation (Rf = 2.05) was in the range of previously conducted column experiments. Discussion   The results confirm previously conducted experiments with clofibric acid where this compound was identified as highly mobile and persistent. The results that diclofenac and ibuprofen are significantly transformed where unexpected as other studies exhibited much lower transformation under saturated conditions at least for diclofenac. However, lower pH values and higher oxygen contents in the unsaturated zone compared to the aquifer may explain this observed high transformation of these compounds at the column experiments. Conclusions   We conclude that irrigation with sewage effluent containing the compounds used in our experiments will lead to an input into groundwater of clofibric acid, whereas diclofenac and ibuprofen will most likely be transformed during the passage. Propyphenazone will be retarded but will most likely occur in groundwater. These results from the column experiments coincide very well with the occurrence of the pharmaceuticals clofibric acid, primidone, and propyphenazone in the first aquifer. Recommendations and Perspective  : The results underline the need to study the sorption of pharmaceuticals on various materials. e.g. organic matter, surfaces at pH values occurring in the unsaturated zone. Future field studies will also include the investigation of desorption behavior in the unsaturated zone.  相似文献   

Evaluating reclamation levels of coastal saline soil using laboratory hyperspectral data     

Z. Shi  M. X. Huang 《Eurasian Soil Science》2007,40(10):1095-1101

Considerable proportions of coastal saline tidelands in China have been reclaimed for agricultural land uses in the past 30 years. This study aims to investigate the potential utility of laboratory hyperspectral data for evaluating the reclamation levels of those saline lands. A coastal region of Shangyu City (Zhejiang Province) was used as the study area, which was then grouped into four subzones according to the reclamation history. Soil samples were collected at each subzone, and they were characterized by high electrical conductivity and sand content and low organic matter; the longer the saline lands have been reclaimed, the lower the electrical conductivity and sand content are and the higher the organic matter content is. These changing trends of the soil chemical and physical properties can be indicated by the laboratory reflectance spectra of the soil samples. Stepwise discriminant analysis (SDA) was applied to select and identify six salient spectral bands at 488, 530, 670, 880, 1400, and 1900 nm. Using derived discriminant functions, saline lands with different historical years of reclamation were classified with an overall accuracy of 86.6% in a self-test and 89.3% in a cross validation. Finally, this study suggests that remotely sensed hyperspectral data serve as promising measures to assess the reclamation levels of coastal saline soil, as opposed to time-consuming field investigations. Published in Russian in Pochvovedenie, 2007, No. 10, pp. 1226–1233. The text was submitted by the authors in English.  相似文献   

Section 4: Sediment and dredged material treatment     

Sabine Ulrike Gerbersdorf 《Journal of Soils and Sediments》2007,7(4):199-199

  相似文献   

Die Kulturpflanzen der griechisch-römischen Welt. Pflanzliche Ressourcen der Antike     

Jürgen Schultze-Motel 《Genetic Resources and Crop Evolution》2005,52(5):641-642

  相似文献   

Identification and characterization of foliar polyphenolic composition in sweetpotato (Ipomoea batatas L.) genotypes   总被引：1，自引：0，他引：1  

Islam MS  Yoshimoto M  Yahara S  Okuno S  Ishiguro K  Yamakawa O 《Journal of agricultural and food chemistry》2002,50(13):3718-3722

Trials over two years were conducted using 1389 sweetpotato (Ipomoea batatas L.) genotypes collected from all over the world to characterize the polyphenolic composition in sweetpotato leaves. Wide variation was observed in relation to their total and individual leaf polyphenolic constituents. In all genotypes studied, the total polyphenol contents of sweetpotato leaf ranged from 1.42 to 17.1 g/100 g dry weight. The six different polyphenolic compounds were identified and quantified by NMR, FABMS, and RPHPLC analysis procedures. This is the first report of polyphenolic compositions in sweetpotato leaves. The relative levels of polyphenolic acids in sweetpotato leaves were as follows: 3,5-di-O-caffeoylquinic acid > 4,5-di-O-caffeoylquinic acid > chlorogenic acid (3-O-caffeoylquinic acid) > 3,4-di-O-caffeoylquinic acid > 3,4,5-tri-O-caffeoylquinic acid > caffeic acid. The highest 3,4,5-tri-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid occurred at 221 and 1183.30 mg/100 g dry weight, respectively.  相似文献   

Inorganic and organic carbon dynamics in forested soils developed on contrasting geology in Slovenia—a stable isotope approach     

Nives Ogrinc  Tjaša Kanduč  Bor Krajnc  Urša Vilhar  Primož Simončič  Lixin Jin 《Journal of Soils and Sediments》2016,16(2):382-395

  相似文献   

Long-term electricity production from soil electrogenic bacteria and high-content screening of biofilm formation on the electrodes     

Samuel Raj Babu Arulmani  Vimalan Jayaraj  Solomon RobinsonDavid Jebakumar 《Journal of Soils and Sediments》2016,16(3):831-841

  相似文献