Sample records for soil biological activity

  1. Monitoring of bioremediation by soil biological activities

    Microsoft Academic Search

    R Margesin; A Zimmerbauer; F Schinner

    2000-01-01

    An evaluation of soil biological activities as a monitoring instrument for the decontamination process of a mineral-oil-contaminated soil was made using measurements of microbial counts, soil respiration, soil biomass and several enzyme activities. The correlations between these parameters and with the levels of hydrocarbon residues were investigated; the effects of different N- and P-sources on hydrocarbon decontamination and soil biological

  2. Soil Biology & Biochemistry 38 (2006) 24482460 Response of soil microbial biomass and enzyme activities to the

    E-print Network

    Minnesota, University of

    2006-01-01

    Soil Biology & Biochemistry 38 (2006) 2448­2460 Response of soil microbial biomass and enzyme as controls to monitor the chamber effect. Elevated CO2 induced mainly an increase of enzyme activities the pool of easily available substrates mainly in the upper soil layers, enzyme regulation (production

  3. Humic substances biological activity at the plant-soil interface

    PubMed Central

    Trevisan, Sara; Francioso, Ornella; Nardi, Serenella

    2010-01-01

    Humic substances (HS) represent the organic material mainly widespread in nature. HS have positive effects on plant physiology by improving soil structure and fertility and by influencing nutrient uptake and root architecture. The biochemical and molecular mechanisms underlying these events are only partially known. HS have been shown to contain auxin and an “auxin-like” activity of humic substances has been proposed, but support to this hypothesis is fragmentary. In this review article, we are giving an overview of available data concerning molecular structures and biological activities of humic substances, with special emphasis on their hormone-like activities. PMID:20495384

  4. Effect of Treated Wastewater Irrigation on Plant Growth and Biological Activity in Three Soil Types

    Microsoft Academic Search

    Maria Adrover; Gabriel Moyŕ; Jaume Vadell

    2012-01-01

    The effects of two types of treated wastewater on soil biological activity were studied in a pot experiment. Four irrigation treatments were tested on both soils sown with barley and unsown soils: distilled water (DW), half-strength Hoagland nutrient solution (NS), treated wastewater from a conventional treatment plant (CWW), and treated wastewater from a lagoon (LWW). Three types of soils were

  5. Soil dissipation and biological activity of metolachlor and S-metolachlor in five soils.

    PubMed

    Shaner, Dale L; Brunk, Galen; Belles, David; Westra, Phil; Nissen, Scott

    2006-07-01

    The resolved isomer of metolachlor, S-metolachlor, was registered in 1997. New formulations based primarily on the S-metolachlor isomer are more active on a gram for gram metolachlor basis than formulations based on a racemic mixture of metolachlor containing a 50:50 ratio of the R and S isomers. The labelled use rates of S-metolachlor-based products were reduced by 35% to give equivalent weed control to metolachlor. However, several companies have recently registered new metolachlor formulations with the same recommended use rates for weed control as S-metolachlor. This research was done to compare the soil behaviour and the biological activity of metolachlor and S-metolachlor in different soils under greenhouse and field conditions. Although K(d) ranged from 1.6 to 6.9 across the five soils, there were no differences in the binding of metolachlor and S-metolachlor to soil or in the rate of soil solution dissipation in a given soil. However, both greenhouse and field studies showed that S-metolachlor was 1.4-3-fold more active than metolachlor against Echinochloa crus-galli (L.) Beauv. in five different soils and that S-metolachlor was more active than metolachlor in three Colorado field locations. When the rates of metolachlor and S-metolachlor were adjusted for S isomer concentrations in the formulations, there were no differences between the formulations in field, greenhouse or bioassay studies. Thus herbicidal activity is due to the S isomers, with the R isomers being largely inactive. PMID:16671061

  6. Temporal and spatial variability of soil biological activity at European scale

    NASA Astrophysics Data System (ADS)

    Mallast, Janine; Rühlmann, Jörg

    2015-04-01

    The CATCH-C project aims to identify and improve the farm-compatibility of Soil Management Practices including to promote productivity, climate change mitigation and soil quality. The focus of this work concentrates on turnover conditions for soil organic matter (SOM). SOM is fundamental for the maintenance of quality and functions of soils while SOM storage is attributed a great importance in terms of climate change mitigation. The turnover conditions depend on soil biological activity characterized by climate and soil properties. Soil biological activity was investigated using two model concepts: a) Re_clim parameter within the ICBM (Introductory Carbon Balance Model) (Andrén & Kätterer 1997) states a climatic factor summarizing soil water storage and soil temperature and its influence on soil biological activity. b) BAT (biological active time) approach derived from model CANDY (CArbon and Nitrogen Dynamic) (Franko & Oelschlägel 1995) expresses the variation of soil moisture, soil temperature and soil aeration as a time scale and an indicator of biological activity for soil organic matter (SOM) turnover. During an earlier stage both model concepts, Re_clim and BAT, were applied based on a monthly data to assess spatial variability of turnover conditions across Europe. This hampers the investigation of temporal variability (e.g. intra-annual). The improved stage integrates daily data of more than 350 weather stations across Europe presented by Klein Tank et al. (2002). All time series data (temperature, precipitation and potential evapotranspiration and soil texture derived from the European Soil Database (JRC 2006)), are used to calculate soil biological activity in the arable layer. The resulting BAT and Re_clim values were spatio-temporal investigated. While "temporal" refers to a long-term trend analysis, "spatial" includes the investigation of soil biological activity variability per environmental zone (ENZ, Metzger et al. 2005 representing similar conditions for precipitation, temperature and relief) to identify ranges and hence turnover conditions for each ENZ. We will discuss the analyzed results of both concepts to assess SOM turnover conditions across Europe for historical weather data and for Spain focusing on climate scenarios. Both concepts help to separate different turnover activities and to indicate organic matter input in order to maintain the given SOM. The assessment could provide recommendations for adaptations of soil management practices. CATCH-C is funded within the 7th Framework Programme for Research, Technological Development and Demonstration, Theme 2 - Biotechnologies, Agriculture & Food (Grant Agreement N° 289782).

  7. IMPACT OF HIGH SOIL PHOSPHORUS LEVELS ON SOIL BIOLOGICAL ACTIVITY AND PHYSICAL PROPERTIES OF OXISOLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the Cerrado region of Brazil to be agriculturally productive, large amount of P fertilizer must be added to overcome the P-fixation capacity of these Oxisol soils. Additions of large amounts of fertilizer affect the chemistry of the soil and may affect the soil physical and biological properties...

  8. Soil Biology & Biochemistry 38 (2006) 32453256 Activities of extracellular enzymes in physically isolated fractions of

    E-print Network

    German, Donovan P.

    2006-01-01

    Soil Biology & Biochemistry 38 (2006) 3245­3256 Activities of extracellular enzymes in physically that carbon-degrading enzymes were abundant in all soil fractions, including macroaggregates, microaggregates, and the clay-sized fraction. The activities of two cellulose-degrading enzymes and a chitin-degrading enzyme

  9. SOIL BIOLOGY AND ECOLOGY

    EPA Science Inventory

    The term "Soil Biology", the study of organism groups living in soil, (plants, lichens, algae, moss, bacteria, fungi, protozoa, nematodes, and arthropods), predates "Soil Ecology", the study of interactions between soil organisms as mediated by the soil physical environment. oil ...

  10. Evaluating the biological activity of oil-polluted soils using a complex index

    NASA Astrophysics Data System (ADS)

    Kabirov, R. R.; Kireeva, N. A.; Kabirov, T. R.; Dubovik, I. Ye.; Yakupova, A. B.; Safiullina, L. M.

    2012-02-01

    A complex index characterizing the biological activity of soils (BAS) is suggested. It is based on an estimate of the level of activity of catalase; the number of heterotrophic and hydrocarbon oxidizing microorganisms, microscopic fungi, algae, and cyanobacteria; and the degree of development of higher plants and insects in the studied soil. The data on using the BAS coefficient for evaluating the efficiency of rehabilitation measures for oil-polluted soils are given. Such measures included introducing the following biological preparations: Lenoil based on a natural consortium of microorganisms Bacillus brevis and Arthrobacter sp.; the Azolen biofertilizer with complex action based on Azotobacter vinelandii; the Belvitamil biopreparation, which is the active silt of pulp and paper production; and a ready-mixed industrial association of aerobic and anaerobic microorganisms that contains hydrocarbon oxidizing microorganisms of the Arthrobacter, Bacillus, Candida, Desulfovibrio, and Pseudomonas genera.

  11. Impact of fungicide mancozeb at different application rates on soil microbial populations, soil biological processes, and enzyme activities in soil.

    PubMed

    Walia, Abhishek; Mehta, Preeti; Guleria, Shiwani; Chauhan, Anjali; Shirkot, C K

    2014-01-01

    The use of fungicides is the continuous exercise particularly in orchard crops where fungal diseases, such as white root rot, have the potential to destroy horticultural crops rendering them unsaleable. In view of above problem, the present study examines the effect of different concentrations of mancozeb (0-2000 ppm) at different incubation periods for their harmful side effects on various microbiological processes, soil microflora, and soil enzymes in alluvial soil (pH 6.8) collected from apple orchards of Shimla in Himachal Pradesh (India). Low concentrations of mancozeb were found to be deleterious towards fungal and actinomycetes population while higher concentrations (1000 and 2000 ppm) were found to be detrimental to soil bacteria. Mancozeb impaired the process of ammonification and nitrification. Similar results were observed for nitrifying and ammonifying bacteria. Phosphorus solubilization was increased by higher concentration of mancozeb, that is, 250 ppm and above. In unamended soil, microbial biomass carbon and carbon mineralization were adversely affected by mancozeb. Soil enzymes, that is, amylase, invertase, and phosphatase showed adverse and disruptive effect when mancozeb used was above 10 ppm in unamended soil. These results conclude that, to lessen the harmful effects in soil biological processes caused by this fungicide, addition of higher amount of nitrogen based fertilizers is required. PMID:25478598

  12. Impact of Fungicide Mancozeb at Different Application Rates on Soil Microbial Populations, Soil Biological Processes, and Enzyme Activities in Soil

    PubMed Central

    Mehta, Preeti; Guleria, Shiwani; Chauhan, Anjali; Shirkot, C. K.

    2014-01-01

    The use of fungicides is the continuous exercise particularly in orchard crops where fungal diseases, such as white root rot, have the potential to destroy horticultural crops rendering them unsaleable. In view of above problem, the present study examines the effect of different concentrations of mancozeb (0–2000?ppm) at different incubation periods for their harmful side effects on various microbiological processes, soil microflora, and soil enzymes in alluvial soil (pH 6.8) collected from apple orchards of Shimla in Himachal Pradesh (India). Low concentrations of mancozeb were found to be deleterious towards fungal and actinomycetes population while higher concentrations (1000 and 2000?ppm) were found to be detrimental to soil bacteria. Mancozeb impaired the process of ammonification and nitrification. Similar results were observed for nitrifying and ammonifying bacteria. Phosphorus solubilization was increased by higher concentration of mancozeb, that is, 250?ppm and above. In unamended soil, microbial biomass carbon and carbon mineralization were adversely affected by mancozeb. Soil enzymes, that is, amylase, invertase, and phosphatase showed adverse and disruptive effect when mancozeb used was above 10?ppm in unamended soil. These results conclude that, to lessen the harmful effects in soil biological processes caused by this fungicide, addition of higher amount of nitrogen based fertilizers is required. PMID:25478598

  13. EFFECT OF NITROGEN AND METAL ADDITIONS ON NITROGEN FIXATION ACTIVITY IN BIOLOGICAL SOIL CRUSTS

    Microsoft Academic Search

    K. Alexander; D. Lui; A. D. Anbar; F. Garcia-Pichel; H. E. Hartnett

    2009-01-01

    Biological soil crusts (BSCs) are diverse consortia of microorganisms that live in intimate association with soils in arid environments. Also called cryptogamic or microbiotic crusts, these communities can include cyanobacteria, algae, heterotrophic bacteria, fungi, lichens, and mosses. Together, these organisms provide many services to their surrounding ecosystems, including reduction of water runoff, promotion of water infiltration, and prevention of soil

  14. EFFECT OF NITROGEN AND METAL ADDITIONS ON NITROGEN FIXATION ACTIVITY IN BIOLOGICAL SOIL CRUSTS

    NASA Astrophysics Data System (ADS)

    Alexander, K.; Lui, D.; Anbar, A. D.; Garcia-Pichel, F.; Hartnett, H. E.

    2009-12-01

    Biological soil crusts (BSCs) are diverse consortia of microorganisms that live in intimate association with soils in arid environments. Also called cryptogamic or microbiotic crusts, these communities can include cyanobacteria, algae, heterotrophic bacteria, fungi, lichens, and mosses. Together, these organisms provide many services to their surrounding ecosystems, including reduction of water runoff, promotion of water infiltration, and prevention of soil erosion. The cyanobacteria and algae also provide fixed carbon (C) to the soil through photosynthesis, and because atmospheric deposition of nitrogen (N) in arid environments is low, the major input of biologically available N comes from cyanobacteria capable of converting nitrogen gas (N2) to ammonium (NH4+). Biological soil crusts are easily destroyed by livestock grazing, motor vehicle travel, and many forms of recreational and agricultural land use. Loss of BSC cover can leave the soil vulnerable to intense erosion that can remove the nutrients necessary to sustain plant and animal life, thus accelerating the process of desertification. In order to preserve existing crusts and encourage the development of new crusts, it is crucial to understand the nutrient requirements of metabolism and growth in these microbial communities. This study investigated the affect of nitrogen and metal additions on N2-fixation activity in cyanobacterially-dominated crusts from the Colorado Plateau near Moab, Utah. Although N2-fixation has been studied in this system before, the affect of nutrient additions on N2-fixation activity has not been documented. The goal of this work was to understand how N and metal supplementation affects crust N metabolism. Three experiments were conducted to observe how N2-fixation activity changed with the addition of N, molybdenum (Mo), and vanadium (V). Molybdenum and vanadium were chosen because they are most commonly found at the active site of the enzyme nitrogenase, the molecule responsible for the biological conversion of N2 to NH4+. The Mo-dependent version of the enzyme is the most efficient, and it is used by the majority of N2-fixing organisms. Elements were added as aqueous solutions of NH4NO3, Na2MoO4, and Na3VO4 respectively. Nitrogen fixation potential was assayed using a modified acetylene reduction technique. Results from the N-addition experiment show that when N is provided, BSC organisms stop N2-fixation activity. This confirms that under natural conditions, the community is limited with respect to N. In general, crusts under Mo-addition fix at higher rates than crusts with no added Mo. This implies that crusts may also be limited with respect to Mo. However, contrary to our expectations, crusts fix at lower rates when V is added as compared to a no-V control. It is possible that this is the result of V-toxicity, or that V competes with the uptake and utilization of available Mo, thus exacerbating Mo-limitation. Experiments are currently underway to investigate how the geochemistry of the soil porewater changes as a result of these nutrient additions.

  15. Effect of cassava mill effluent on biological activity of soil microbial community.

    PubMed

    Igbinosa, Etinosa O

    2015-07-01

    This study assessed the effect of cassava effluent on soil microbiological characteristics and enzymatic activities were investigated in soil samples. Soil properties and heavy metal concentrations were evaluated using standard soil analytical and spectroscopic methods, respectively. The microbiological parameters measured include microbial biomass carbon, basal soil respiration, catalase, urease, dehydrogenase activities and number of culturable aerobic bacteria, fungi and actinomycetes. The pH and temperature regime vary significantly (p?Soil organic carbon content gave significant positive correlations with microbial biomass carbon, basal soil respiration, catalase activity and dehydrogenase activity (r?=?0.450, 0.461, 0.574 and 0.591 at p?soil microbial density demonstrates a marked decrease in total culturable numbers of the different microbial groups of the polluted soil samples. Soil contamination decreased catalase, urease and dehydrogenase activities. The findings revealed that soil enzymes can be used as indices of soil contamination and bio-indicator of soil quality. PMID:26055654

  16. Soil biology for resilient healthy soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    What is a resilient healthy soil? A resilient soil is capable of recovering or adapting to stress; the health of the living/biological component of the soil is crucial for soil resiliency. Soil health is tightly coupled to the concept of soil quality (Text Box 1) and the terms are frequently used ...

  17. Soil invertebrate activity in biological crusts on tropical inselbergs A.VAULIK, C. KOUNDA-KIKI, C. SARTHOU & J.F. PONGE

    E-print Network

    Paris-Sud XI, Université de

    1 Soil invertebrate activity in biological crusts on tropical inselbergs A.VAÇULIK, C. KOUNDA invertebrates, in particular enchytraeid worms, are important for the accumulation of organic matter on granite: Soil invertebrate activity in biological crusts Introduction Inselbergs protrude from rain forests

  18. Effect of different crops on soil organic matter and biological activity in Oxisols under three different crops

    NASA Astrophysics Data System (ADS)

    Toledo, Diana Marcela; Arzuaga, Silvia; Dalurzo, Humberto; Zornoza, Raúl; Vazquez, Sara

    2015-04-01

    The objective of this work was to evaluate changes in soil organic matter in Oxisols under different crops compared to native rainforest, and to assess if acid phosphatase activity (APA) could be a good indicator for SOC changes and soil quality. The experimental design consisted of four completely randomized blocks with four treatments: subtropical rainforest (F); yerba mate crop (I) (Ilex paraguariensis SH.); citrus crop (C) (Citrus unshiu Marc); and tobacco crop (T) (Nicotiana tabacum L.). Soil samples were taken at 0-10; 10-20 and 20-30 cm depths. The variables measured were soil organic carbon (SOC), APA, clay content, pH, total nitrogen (Nt), available phosphorus (P) and CO2 emissions. All data were analyzed by ANOVA to assess the effects of land-use changes. The treatment means were compared through Duncan's multiple range tests (p<0.05). The relationship between variables was determined with a simple correlation analysis and with a multiple linear regression analysis through the stepwise method. These soils showed an acid reaction and their clay content was over 650 g kg-1 for the three depths. SOC and N contents were higher in native soils, intermediate for the citrus crop, and lower under both tobacco and yerba mate crops. CO2 emissions were higher in the rainforest (47.32 kg ha-1 of CO2) than in cultivated soils, which indicates that biological activity is enhanced in rainforest soils where substrates for soil biota and fauna are more readily available. The variability of 76% in APA was explained by total nitrogen, which is closely related to soil organic matter, and by available P. Conversion of subtropical rainforests into agricultural lands reduced SOC content and acid phosphatase activity, thereby lowering soil quality. In this study, acid phosphatase activity proved to be a sensitive indicator to detect changes from pristine to cropped soils, but it failed to distinguish differences among crop systems.

  19. SOIL DISSIPATION AND BIOLOGICAL ACTIVITY OF METOLACHLOR AND S-METOLACHLOR IN FIVE SOILS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The resolved isomer of metolachlor, S-metolachlor, was registered in 1997. New formulations based primarily on the S-metolachlor isomer are more active on a gram for gram metolachlor basis than formulations based on a racemic mixture of metolachlor containing a 50:50 ratio of the R and S isomers. T...

  20. Evaluation of the soil biological activity in a remediation soil assay using organic amendments and vegetal cover.

    PubMed

    Sastre-Conde, Isabel; Cabezas, José Gerardo; Guerrero, Ana; Vicente, María Angeles; Lobo, María Del Carmen

    2007-05-25

    The recovery of a degraded soil was assayed in greenhouse conditions by applying organic amendments and revegetation with grasses. Two types of organic residues were used: sewage sludge composted with pruning waste (CPW), at 8.5 and 85 Mg ha(-1) and sewage sludge treated by thermal drying (TD), at 22 and 46 Mg ha(-1). The vegetal cover was established by sowing different herbaceous species commonly used in the revegetation of degraded alkaline soils (100 and 200 Kg of seeds ha(-1)). The chemical soil parameters and enzymatic activities (alkaline phosphatase, urease, and beta-glucosidase) and the vegetal biomass were evaluated. The type of amendment and the doses applied had different effects on the soil characteristics. However sowing dose did not have a significant effect on the parameters analysed. Organic matter was the only soil parameter affected by the interaction between the sowing rate and the amendment dose. The phosphatase and glucosidase activities showed significant correlation with the percentage of N in the leaves and stems, furthermore the phosphate activity was significantly related to the dry weight of leaves and stems. PMID:17306865

  1. Biological Soil Crusts: Characteristics and Distribution

    Microsoft Academic Search

    J. Belnap; B. Büdel; O. L. Lange

    \\u000a Biological soil crusts result from an intimate association between soil particles and cyanobacteria, algae, microfungi, lichens,\\u000a and bryophytes (in different proportions) which live within, or immediately on top of, the uppermost millimeters of soil.\\u000a Soil particles are aggregated through the presence and activity of these biota, and the resultant living crust covers the\\u000a surface of the ground as a coherent

  2. Amendments and mulches improve the biological quality of soils degraded by mining activities in SE Spain

    NASA Astrophysics Data System (ADS)

    Luna Ramos, Lourdes; Miralles Mellado, Isabel; Hernández Fernández, María Teresa; García Izquierdo, Carlos; Solé Benet, Albert

    2014-05-01

    Mining and quarrying activities generate negative visual impacts in the landscape and a loss of environmental quality. Substrate properties at the end of mining are in general not suitable for plant growth, even native ones. In an experimental soil restoration in limestone quarries from Sierra de Gádor (Almería), SE Spain, the effect of organic amendment (sewage sludge, compost from the organic fraction of domestic waste or non-amendment) combined or not with two different kind of mulches (fine gravel, chopped forest residue) was tested by triplicate in 5 x 5 m plots with the aim to improve soil/substrate properties and to reduce evaporation and erosion. In each experimental plot 75 native plants (Stipa tenacissima, Anthyllis terniflora and Anthyllis cytisoides) were planted. Effects of adding organic amendments and mulches on some soil microbiological and biochemical parameters (microbial biomass carbon, basal respiration and different enzymatic activities, such as dehydrogenase, phosphatase, ?-glucosidase and urease) were analyzed 5 years after the start of the experiment. Vegetation growth was also monitored. The two-way ANOVA, using as factors amendment and mulch, showed a significant positive influence of organic amendments on microbial biomass (Cmic), basal respiration and some enzymatic activities related to the cycles of C and N. The highest values of these parameters were obtained with compost. The influence of the mulch factor and its interactions with the amendment factor on the measured variables did not follow a clear trend with respect the measured parameters. Mulching did not improved significantly (p<0.05) the positive effect of organic amendments on Cmic although Cmic values increased with the incorporation of "forest chopped residue" and decreased with gravel incorporation. In general, both type of mulch decreased or have no effect on the microbial activity detected in the amended soils, with the only exception of the forest chopped residue, which increased phosphatase activity in the compost amended soil. Plant growth was significantly higher in amended soils than in the control, but it is remarkable that the mulch type "forest chopped residue" had a negative effect on vegetation growth. The addition of organic amendments, especially compost from the organic fraction of domestic wastes, is beneficial to restore degraded or man-made soils from quarrying areas because they stimulate microbial growth and activity, resulting in mineralization of nutrients necessary for plants and increasing soil fertility and quality. However, after 5 years the effects of the mulch "forest chopped residue", on the improvement of soil or substrate quality are not clear.

  3. Spatial and temporal patterns of soil biological activity in a forest and an old field

    Microsoft Academic Search

    Josef H. Görres; Marnie J. Dichiaro; Jodi B. Lyons; José A. Amador

    1998-01-01

    The spatial distribution of C mineralization, nematode density, organic matter content and soil moisture were determined for a forest and an old field soil in the northeastern U.S.A. over the course of a year. The data were analyzed using univariate, multivariate and geostatistical methods. The forest soil had a higher C mineralization rate, soil moisture content and nematode density than

  4. Engelmann Spruce (Picea engelmannii) as a biological monitor of changes in soil metal loading related to past mining activity

    USGS Publications Warehouse

    Witte, K.M.; Wanty, R.B.; Ridley, W.I.

    2004-01-01

    Engelmann spruce (Picea engelmannii) is the dominant tree species in many abandoned mine areas of the Rocky Mountains. It is long-lived, and therefore, may act as a long term biological monitor of changes in soil chemistry caused by past mining activity. In this study, laser ablation inductively coupled mass spectrometry (LA-ICPMS) was used to analyze individual tree rings of Engelmann spruce for Fe, Zn, Cu, Cd, Mn, Pb and Sr concentrations. Cores were obtained from trees growing in tailings-impacted and control (non-tailings impacted) sites near the Waldorf mine (Waldorf, CO, USA). Zinc, Cu, Fe, Cd, Pb and Sr concentrations remained low and consistent over time in the control tree rings. However, in the tailings impacted cores, concentrations of Zn, Cu, Fe and Cd increase significantly in post-mining rings. In addition, Zn, Cu, Fe, and Cd concentrations in pre-mining rings of both the control and tailings impacted cores are similar, indicating that present day soil concentrations of these elements in the control area are a reasonable estimation of background for this area. Lead and Sr concentrations in control and tailings-impacted rings remained similar and relatively constant through time and are not useful in determining changes in soil chemistry due to past mining activity. ?? 2004 Elsevier Ltd. All rights reserved.

  5. Antibiotic Pigment from Desert Soil Actinomycetes; Biological Activity, Purification and Chemical Screening

    PubMed Central

    Selvameenal, L.; Radhakrishnan, M.; Balagurunathan, R.

    2009-01-01

    An actinomycete strain, Streptomyces hygroscopicus subsp. ossamyceticus (strain D10) was isolated from Thar Desert soil, Rajasthan during the year 2006 and found to produce a yellow color pigment with antibiotic activity. Crude pigment was produced from strain D10 by solid state fermentation using wheat bran medium followed by extraction with ethyl acetate. The antimicrobial activity of the crude pigment was evaluated against drug resistant pathogens such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Staphylococcus aureus, extended spectrum ?-lactamase producing cultures of Escherichia coli, Pseudomonas aeruginosa and Klebsiella sp. About 420 mg of crude pigment was produced per 10 g of wheat bran medium. In the disc diffusion method the crude ethyl acetate extract showed a minimum of 10 mm inhibition against Klebsiella sp. and maximum of 19 mm of inhibition against Escherichia coli. The crude pigment was partially purified using thin layer chromatography with the solvent system chloroform:methanol (30:70) and the Rf value was calculated as 0.768. Antimicrobial activity of the partially purified compound from thin layer chromatography was determined using the bioautography method. The purified pigment showed minimum of 15 mm inhibition against Klebsiella sp. and a maximum of 23 mm of inhibition against vancomycin-resistant Staphylococcus aureus in the disc diffusion method. Based on the results of chemical screening, the pigment was tentatively identified as group of sugar containing molecules. PMID:20502566

  6. Biodiversity and biological degradation of soil

    Microsoft Academic Search

    Upasana Mishra; Dolly Wattal Dhar

    2004-01-01

    Soils contain enormous numbers of diverse living organisms assembled in complex and varied communities. Microscopic examination\\u000a of a soil sample reveals the presence of billions of organisms like nematodes, protozoa, fungi, algae, actinomycetes, bacteria\\u000a and cyanobacteria. These diverse organisms interact in the ecosystem, forming a complex web of biological activity. Environmental\\u000a factors, such as temperature, moisture and acidity, as well

  7. Soil Biology & Biochemistry 39 (2007) 27012711 Carbon structure and enzyme activities in alpine and forest ecosystems

    E-print Network

    Neff, Jason

    2007-01-01

    matter; Forest; Alpine 1. Introduction The physical and chemical changes that occur in soils during physical and chemical methods available to separate soils into fractions with different functional of decomposition between plant residues and physically stabilized C. The general chemical characteri

  8. A comparison of soil climate and biological activity along an elevation gradient in the eastern Mojave Desert

    USGS Publications Warehouse

    Amundson, R.G.; Chadwick, O.A.; Sowers, J.M.

    1989-01-01

    Soil temperature, moisture, and CO2 were monitored at four sites along an elevation transect in the eastern Mojave Desert from January to October, 1987. Climate appeared to be the major factor controlling CO2 partial pressures, primarily through its influence of rates of biological reactions, vegetation densities, and organic matter production. With increasing elevation, and increasing actual evapotranspiration, the organic C, plant density, and the CO2 content of the soils increased. Between January and May, soil CO2 concentrations at a given site were closely related to variations in soil temperature. In July and October, temperatures had little effect on CO2, presumably due to low soil moisture levels. Up to 75% of litter placed in the field in March was lost by October whereas, for the 3 lower elevations, less than 10% of the litter placed in the field in April was lost through decomposition processes. ?? 1989 Springer-Verlag.

  9. Effects of Some Plant Residues on Nitrogen Mineralization and Biological Activity in Soils

    Microsoft Academic Search

    Emine Erman KARA

    The objective of this experiment was to determine the rate of decomposition and nitrogen mineralization of plant residues in soil under laboratory conditions. The experiment consisted of six treatments: control, industrial tobacco residues, rice straw, rice straw + mineral nitrogen, rice husks and rice husks+mineral nitrogen. The plant materials were added at a rate of 2000 mg\\/kgC and the amount

  10. Long-term impact of land management in soil biological processes can be assessed by fingerprint of dissolved organic carbon and peroxidase activity in topsoil and subsoil

    NASA Astrophysics Data System (ADS)

    Hernandez-Soriano, Maria C.; Maclean, Jamie L.; Dalal, Ram C.; Menzies, Neal W.; Kopittke, Peter M.

    2015-04-01

    The dissolved organic carbon (DOC) is a highly dynamic pool, directly related to biological functions and to the stabilization of organic carbon (OC) through interaction with the mineral phase. Therefore, the characterization of the main components of DOC can be linked to the metabolic status of soil and the turnover of OC and provides a sensitive approach to evaluate the impact of land use on OC turnover in soils. Accordingly, the objective of this study was to derive relationships between DOC characteristics and biochemical activity in soils under contrasting land management. The soil solution was isolated from topsoil and subsoil for three soils (Vertisol, Ferralsol, Acrisol, World Reference Base 2014) collected from undisturbed areas and from a location(s) immediately adjacent which has a long history of agricultural, pasture or afforestation use (>20 years) by centrifugation at 4000 rpm (20 min, 25 °C. The fingerprint of DOC was obtained to identify OC functionalities by spectrofluorometric analyses and Excitation-Emission matrices (EEM) were obtained for all samples. The excitation wavelengths were increased from 250 to 400 nm in 5-nm steps for each excitation wavelength, and emission was detected from 250 to 500 nm in 0.5-nm steps and. Humification index (HIX), freshness index (FrI), fluorescence index (FI) and redox index (RI) were derived from the EEMs. Extracellular laccase activity was examined by monitoring the oxidation of 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) at 420 nm. The EEMs revealed a depletion of the humic-like component (250soils under pasture or cropping compared to adjacent soils under native vegetation. For soil under pasture, the subsoil appeared enriched in the humic-like component compared to the subsoil under native vegetation. A component assigned to aromatic proteins was identified in the subsoil of the cropping area. The HIX consistently decreased for cropping areas compared to soil under native vegetation across the different soils. However, HIX decreased for the Ferralsol under pasture compared to areas under native vegetation, but increased for the Acrisol under pasture. Generally, HIX is substantially related to land use, with the highest HIX values determined for soils under native vegetation. Laccase activity was generally higher for topsoils collected from undisturbed areas for the three soils examined and a significant decrease in the enzyme activity was determined for soils collected from the corresponding adjacent crop land. The rate of ABTS oxidation varied for the different soils following the order Vertisol>Acrisol>Ferralsol and was always higher for the topsoils compared to the corresponding subsoils. Overall, results indicate that land management has a strong impact on soil biological activity. Importantly, such impact is directly linked to changes in the composition of soil OC, particularly the transformation of OC inputs into oxidized products that can contribute to OC build up in soil. For the first time, we have utilized DOC fingerprinting and extracellular laccase activity as complementary techniques to examine changes in OC speciation in soil solutions. This approach provides a suitable link between variations in biological functions and OC dynamics.

  11. Changes in the biological activity of chestnut soils upon the long-term application of fertilizers in a rotation with oil-bearing crops

    NASA Astrophysics Data System (ADS)

    Eleshev, R. E.; Bakenova, Z. B.

    2012-11-01

    Experimental studies showed that irrigated chestnut soils on the piedmont of the Zailiiskiy Alatau Range are characterized by the moderate activity of the hydrolytic and redox enzymes. The use of these soils in the crop rotation system increases the hydrolytic activity of the enzymes (invertase, urease, and ATP synthase) by 30% in comparison with the monoculture; at the same time, it does not have a significant impact on the changes in the biological activity of the redox enzymes (catalase and dehydrogenase). The hydrolytic activity of the soils is activated to a greater extent in the crop rotation and in the monoculture against the background application of organic fertilizers. In this case, the recommended rates of mineral fertilizers do not inhibit the activity of the hydrolytic and redox enzymes. An increase in the hydrolytic activity of the enzymes directly affects the yield of oilseed flax. Therefore, indices of the hydrolytic activity of soils can be used as a test for the diagnostics of the efficiency of fertilizers both in crop rotation and monoculture systems.

  12. An Introduction to Biological Soil Crusts

    NSDL National Science Digital Library

    Biological soil crusts are the feature of this USGS Canyonlands Research Station website. The site provides an introduction to biological soil crusts with linked images, divided into the following topics: nomenclature of the crusts- crytogamic, microbiotic, crytobiotic, and microphytic crusts, structure and formation, species composition, ecological functions, response to disturbance, future, and a glossary. In addition, the site provides links to other Canyonlands Research Station webages including an advanced page with a downloadable 90-page report on soil crusts, a gallery of biological soil crust images and figures, references, the Canyon Country Ecosystems Research Site (CCERS), and other related links.

  13. Biological Phosphorus Cycling in Arctic and Alpine Soils

    Microsoft Academic Search

    Michael N. Weintraub

    \\u000a Organic phosphorus (P) is the predominant source of plant and microbial P in many arctic and alpine soils due to high moisture\\u000a and low temperatures, which result in the accumulation of soil organic matter and P cycles dominated by biological processes.\\u000a It has been hypothesized that the organic P accumulates in cold soils due to the inhibition of microbial activity

  14. Color characterization of Arctic Biological Soil Crusts

    NASA Astrophysics Data System (ADS)

    Mele, Giacono; Gargiulo, Laura; Ventura, Stefano

    2015-04-01

    Global climate change makes large areas lacking the vegetation coverage continuously available to primary colonization by biological soil crusts (BSCs). This happens in many different environments, included high mountains and Polar Regions where new areas can become available due to glaciers retreat. Presence of BSCs leads to the stabilization of the substrate and to a possible development of protosoil, with an increase of fertility and resilience against erosion. Polar BSCs can exhibit many different proportions of cyanobacteria, algae, microfungi, lichens, and bryophytes which induce a large variability of the crust morphology and specific ecosystem functions. An effective and easy way for identifying the BSCs in the field would be very useful to rapidly recognize their development stage and help in understanding the overall impact of climate change in the delicate polar environments. Color analysis has long been applied as an easily measurable physical attribute of soil closely correlated with pedogenic processes and some soil functions. In this preliminary work we used RGB and CIE-L*a*b* color models in order to physically characterize fourteen different BSCs identified in Spitsbergen island of Svalbard archipelago in Arctic Ocean at 79° north latitude. We found that the "redness parameter "a*" of CIE-L*a*b* model was well correlated to the succession process of some BSCs at given geomorphology condition. Most of color parameters showed, moreover, a great potential to be correlated to photosynthetic activity and other ecosystem functions of BSCs.

  15. Viking Biology Experiments and the Martian soil

    NASA Technical Reports Server (NTRS)

    Banin, Amos

    1989-01-01

    The Viking Biology Experiments (VBE) are the most informative database on the wet chemistry and reactivity of the Martian soil available today. The simulation and chemical interpretation of the results have given valuable hints towards the characterization of the soils' mineralogy, adsorption properties, pH and redox. The characterization of Mars' soil on the basis of ten years of labelled release (LR) and other VBE simulations are reviewed.

  16. Soil enzyme activities and their indication for fertility of urban forest soil

    Microsoft Academic Search

    Qihua Shan; Yuanchun Yu; Jian Yu; Jinchi Zhang

    2008-01-01

    To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as\\u000a the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated.\\u000a Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase,\\u000a alkaline phosphatase, and cellulase were determined by

  17. PARTICULATE AND BIOLOGICALLY ACTIVE SOIL CARBON POOLS UNDER GRAZED AND UNGRAZED BERMUDAGRASS IN THE SOUTHERN PIEDMONT USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of forage management strategies on carbon cycling is of importance to the understanding of greenhouse gas emissions, agronomic productivity, and changes in soil quality. Particulate organic C (POC), soil microbial biomass C (SMBC), and potential C mineralization (CMIN) were evaluated duri...

  18. The role of biological soil crusts on soil moisture

    NASA Astrophysics Data System (ADS)

    Chamizo, S.; Cantón, Y.; Lázaro, R.; Rodriguez-Caballero, E.; Domingo, F.

    2012-04-01

    In water-limited ecosystems, water becomes the most important driver for plant productivity. In these systems, spatial distribution of water resources is not random but organized into a mosaic of water-depletion areas linked to water-accumulation areas. In other words, water is transferred from interplant patches that act as source areas to vegetation patches that act as sinks of this resource. Thus, structure and functioning of interplant patches have a decisive role in water redistribution and distribution patterns of vegetation. Soil surface in the interplant spaces of most arid and semiarid ecosystems is covered by biological soil crusts (BSCs). These organisms regulate water fluxes into and through soils and play major roles in local hydrological processes. In the last years, the role of these organisms in infiltration and runoff has gained increased importance and a better knowledge about their effects on these processes has been acquired. However, the role of BSCs in other important components of the water balance such as evaporation or soil moisture has been scarcely studied, so that their effects on these processes remain unknown. The objective of this work is to examine the influence of BSCs on soil moisture regimes in the top profile of the soil in two semiarid ecosystems of SE Spain with contrasting soil texture and where BSCs are well-represented. Soil moisture content at 0.03 and 0.10 m was monitored under two representative types of BSCs, a dark cyanobacteria-dominated BSC and a light-coloured lichen-dominated BSC, and in soils where these BSCs were removed by scraping, at both study sites. Our results show that, under high water conditions, removal of BSCs leads to a decrease in soil moisture compared to soils covered by BSCs. Decrease in soil moisture due to BSC removal namely affects moisture in the upper layer of the soil (0.03 m), but has little impact in deeper soil (0.10 m). Evaporation is also generally faster in soils with no BSCs than in soils covered by them. The type of BSC influences soil moisture in a different way depending on soil water conditions. Under high water content conditions, soil water loss is faster and soil moisture content lower under cyanobacterial than under lichen BSCs, due to higher infiltration promoted by lichens. On the contrary, under low water content conditions, lichen-crusted soils dry out faster and exhibit less moisture than cyanobacteria-crusted ones, attributed to the larger porosity and subsequent greater evaporative losses in lichen- than in cyanobacteria-crusted soils. We found higher moisture in coarse-textured soils than in fine-textured ones, despite the higher water retention capacity of the latter soils. More favourable conditions in the coarser soils, which had greater organic matter content, aggregate stability and were subject to less water stress due to its proximity to the coast, seems to contribute to this increased soil moisture content. BSCs therefore play an important role on the maintenance of water availability in the interplant spaces, thereby strongly affecting soil physical and biological processes, and the potential for emergence establishment and survival of plants in semiarid ecosystems.

  19. Soil stabilization by biological soil crusts in arid Tunisia

    NASA Astrophysics Data System (ADS)

    Guidez, Sabine; Couté, Alain; Bardat, Jacques

    2015-04-01

    As part of the fight against desertification (LCD) in arid Tunisia, we have been able to highlight the important role played by biological soil crusts (BSC) in soil stabilization. The identification of the major species of cyanobacteria, lichens and bryophytes, their adaptation and terrestrial colonization strategies in this high climatic constraints area through their morpho-anatomical criteria have been set. In addition to their biological composition, their internal arrangement (i.e. texture and microstructure) reflects the structural stability of BSC against erosion. Precisely, the aggregative power of cyanobacteria and their ways of moving inside a soil, the capacity of mosses to grow through the sediments and lichens ability to bind at particles on surface, thus stabilizing the substrate have been demonstrated. Then, the three biological components ability to capture soil particles has been widely illustrated, proving the major environmental contribution of BSC in arid areas biological crusts formation, providing that soils will experience an increase of organic matter and fine particles rates subsequently gaining faster and better stability. Although the thickness and the morphology of crusts are related to the cover rates of these different biological components, the water properties of the latter, studied at the environmental SEM, illustrate their important role in altering the water cycle. Thus, the mixed crusts, i.e. with good presence of three biological components, cause the highest runoff rates by their ability to retain the water and spread on the surface. In spite of a swelling coefficient in presence of water higher than cryptogams, the cyanobacterial crusts located in newly stabilized areas of our studied region, remain finally insufficiently dense to impact surface hydrology. But, we showed after all that the cyanobacteria, pioneer species, have a certain environmental role. The lichen crusts cause a increased runoff because the lichens have a ability to extend them horizontally on the soil surface. Despite the water capture for their metabolism, the water flows; it isn't released in the depth. The moss crusts show an opposite process with an increased infiltration thanks to the possibility of a vertical transit of water through their sheets, stem and roots. So, in relation to bare soils, a crust with a good microbial and cryptogamic development causes more runoff. As part of the fight against the desertification in arid Tunisia, hydrological impact of BSC may lead to elaborate some ecosystem strategies in water and soils management. Indeed, climate aridity is not synonymous with edaphic aridity.

  20. Effects of soil type and farm management on soil ecological functional genes and microbial activities

    SciTech Connect

    Reeve, Jennifer [Washington State University; Schadt, Christopher Warren [ORNL; Carpenter-Boggs, Lynne [Washington State University; Kang, S. [University of Oklahoma; Zhou, Jizhong [University of Oklahoma, Norman; Reganold, John P. [Washington State University

    2010-01-01

    Relationships between soil microbial diversity and soil function are the subject of much debate. Process-level analyses have shown that microbial function varies with soil type and responds to soil management. However, such measurements cannot determine the role of community structure and diversity in soil function. The goal of this study was to investigate the role of gene frequency and diversity, measured by microarray analysis, on soil processes. The study was conducted in an agro-ecosystem characterized by contrasting management practices and soil types. Eight pairs of adjacent commercial organic and conventional strawberry fields were matched for soil type, strawberry variety, and all other environmental conditions. Soil physical, chemical and biological analyses were conducted including functional gene microarrays (FGA). Soil physical and chemical characteristics were primarily determined by soil textural type (coarse vs fine-textured), but biological and FGA measures were more influenced by management (organic vs conventional). Organically managed soils consistently showed greater functional activity as well as FGA signal intensity (SI) and diversity. Overall FGA SI and diversity were correlated to total soil microbial biomass. Functional gene group SI and/or diversity were correlated to related soil chemical and biological measures such as microbial biomass, cellulose, dehydrogenase, ammonium and sulfur. Management was the dominant determinant of soil biology as measured by microbial gene frequency and diversity, which paralleled measured microbial processes.

  1. Orchard floor management effects on nitrogen fertility and soil biological activity in a newly established organic apple orchard

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient supply in organic systems is dependent on mineralization of organic matter; however, the intensive cultivation commonly used to control weeds can disrupt biological processes and cause undue loss of organic matter. Here we address the often-competing goals of organic fertility and weed con...

  2. Soil Biology & Biochemistry 38 (2006) 30013002 A synthesis of soil biodiversity and ecosystem functioning in

    E-print Network

    Wall, Diana

    2006-01-01

    Soil Biology & Biochemistry 38 (2006) 3001­3002 Editorial A synthesis of soil biodiversity relationships between biodiversity and ecosystem functions fundamental to all soils. This issue of Soil Biology, however, is how these changes will affect biodiversity and the ecological processes mediated by soil

  3. Active Biological Materials

    PubMed Central

    Fletcher, Daniel A.; Geissler, Phillip L.

    2011-01-01

    Cells make use of dynamic internal structures to control shape and create movement. By consuming energy to assemble into highly organized systems of interacting parts, these structures can generate force and resist compression, as well as adaptively change in response to their environment. Recent progress in reconstituting cytoskeletal structures in vitro has provided an opportunity to characterize the mechanics and dynamics of filament networks formed from purified proteins. Results indicate that a complex interplay between length scales and timescales underlies the mechanical responses of these systems and that energy consumption, as manifested in molecular motor activity and cytoskeletal filament growth, can drive transitions between distinct material states. This review discusses the basic characteristics of these active biological materials that set them apart from conventional materials and that create a rich array of unique behaviors. PMID:18999991

  4. Influence of organic and mineral fertilisers on soil biological and physical properties

    Microsoft Academic Search

    S Marinari; G Masciandaro; B Ceccanti; S Grego

    2000-01-01

    The aim of this research was to study in a field experiment the influence of different fertiliser applications on soil biological and physical properties. Vermicompost (VC) from biological sludge, stabilised dairy manure or mineral nitrogen fertiliser (NH4NO3) were applied to a corn crop (Zea mays L.) at 200 kg N ha?1. Soil enzyme activity (acid phosphatase, dehydrogenase and protease BAA)

  5. Reconstruction of food webs in biological soil crusts using metabolomics.

    NASA Astrophysics Data System (ADS)

    Baran, Richard; Brodie, Eoin L.; Mayberry-Lewis, Jazmine; Nunes Da Rocha, Ulisses; Bowen, Benjamin P.; Karaoz, Ulas; Cadillo-Quiroz, Hinsby; Garcia-Pichel, Ferran; Northen, Trent R.

    2015-04-01

    Biological soil crusts (BSCs) are communities of organisms inhabiting the upper layer of soil in arid environments. BSCs persist in a dessicated dormant state for extended periods of time and experience pulsed periods of activity facilitated by infrequent rainfall. Microcoleus vaginatus, a non-diazotrophic filamentous cyanobacterium, is the key primary producer in BSCs in the Colorado Plateau and is an early pioneer in colonizing arid environments. Over decades, BSCs proceed through developmental stages with increasing complexity of constituent microorganisms and macroscopic properties. Metabolic interactions among BSC microorganisms probably play a key role in determining the community dynamics and cycling of carbon and nitrogen. However, these metabolic interactions have not been studied systematically. Towards this goal, exometabolomic analysis was performed using liquid chromatography coupled to tandem mass spectrometry on biological soil crust pore water and spent media of key soil bacterial isolates. Comparison of spent vs. fresh media was used to determine uptake or release of metabolites by specific microbes. To link pore water experiments with isolate studies, metabolite extracts of authentic soil were used as supplements for isolate exometabolomic profiling. Our soil metabolomics methods detected hundreds of metabolites from soils including many novel compounds. Overall, Microcoleus vaginatus was found to release and utilize a broad range of metabolites. Many of these metabolites were also taken up by heterotrophs but there were surprisingly few metabolites uptaken by all isolates. This points to a competition for a small set of central metabolites and specialization of individual heterotrophs towards a diverse pool of available organic nutrients. Overall, these data suggest that understanding the substrate specialization of biological soil crust bacteria can help link community structure to nutrient cycling.

  6. [Biological soil crust nitrogenase activity and its responses to hydro-thermic factors in different erosion regions on the Loess Plateau, China].

    PubMed

    Ming, Jiao; Zhao, Yun-Ge; Xu, Ming-Xiang; Yang, Li-Na; Wang, Ai-Guo

    2013-07-01

    Based on field survey, the biological soil crusts at their stable development stage were collected from the water erosion region, water-wind erosion region, and wind erosion region on the Loess Plateau, aimed to study the effects of the variations of moisture and temperature on the crusts nitrogenase activity (NA). The NA of the crusts in the erosion regions decreased in the order of water erosion region (127.7 micromol x m(-2) x h(-1)) > water-wind erosion region (34.6 micromol x m(-2) x h(-1)) > wind erosion region (6.0 micromol x m(-2) x h(-1)), and the optimal temperature for the crust nitrogen fixation was 35 degrees C, 25 degrees C, and 15 degrees C, respectively. At the optimal temperature and 100% -40% field water-holding capacity, the NA of the crusts from the water erosion and water-wind erosion regions had no significant difference. The NA of the crusts from the wind erosion region was more sensitive to the variation of moisture, showing a dramatic decline when the moisture decreased to 80% field water-holding capacity, and totally lost when the moisture decreased to 20% field water-holding capacity. The differences in the NA of the crusts from the three erosion regions and the responses of the NA to the variations of moisture and temperature were likely associated with the climate, environment, and the crust species composition. PMID:24175513

  7. FIELD MANAGEMENT EFFECTS ON SOIL ENZYME ACTIVITIES

    Microsoft Academic Search

    Alina Dora Samuel; Cornel Domua; Cornelia Ciobanu

    Agricultural practices that reduce soil degradation and improve agricultural sustainability are needed particularly for preluvosoil. No-tillage planting causes minimal soil disturbance and combined with crop rotation may hold potential to meet these goals. Soil enzyme activities can provide information on how soil management affects the soil potential to perform processes, such as decomposi- tion and nutrient cycling. Soil enzyme activities

  8. [Ecological effect of hygroscopic and condensate water on biological soil crusts in Shapotou region of China].

    PubMed

    Pan, Yan-Xia; Wang, Xin-Ping; Zhang, Ya-Feng; Hu, Rui

    2013-03-01

    By the method of field experiment combined with laboratory analysis, this paper studied the ecological significance of hygroscopic and condensate water on the biological soil crusts in the vegetation sand-fixing area in Shapotou region of China. In the study area, 90% of hygroscopic and condensate water was within the 3 cm soil depth, which didn' t affect the surface soil water content. The hygroscopic and condensate water generated at night involved in the exchange process of soil surface water and atmosphere water vapor, made up the loss of soil water due to the evaporation during the day, and made the surface soil water not reduced rapidly. The amount of the generated hygroscopic and condensate water had a positive correlation with the chlorophyll content of biological soil crusts, indicating that the hygroscopic and condensate water could improve the growth activity of the biological soil crusts, and thus, benefit the biomass accumulation of the crusts. PMID:23755477

  9. Active Microwave Soil Moisture Research

    Microsoft Academic Search

    M. CRAIG DOBSON; FAWWAZ T. ULABY

    1986-01-01

    This paper summarizes the progress achieved in the active microwave remote sensing of soil moisture during the four years of the AgRISTARS program. Within that time period, from about 1980 to 1984, significant progress was made toward understanding 1) the fundamental dielectric properties of moist soils, 2) the influence of surface boundary conditions, and 3) the effects of intervening vegetation

  10. Active synthetic soil

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W. (inventor.); Henninger, Donald L. (inventor.); Allen, Earl R. (inventor.); Golden, Dadigamuwage C. (inventor.)

    1995-01-01

    A synthetic soil/fertilizer for horticultural application having all the agronutrients essential for plant growth is disclosed. The soil comprises a synthetic apatite fertilizer having sulfur, magnesium, and micronutrients dispersed in a calcium phosphate matrix, a zeolite cation exchange medium saturated with a charge of potassium and nitrogen cations, and an optional pH buffer. Moisture dissolves the apatite and mobilizes the nutrient elements from the apatite matrix and the zeolite charge sites.

  11. Active synthetic soil

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W. (Inventor); Henninger, Donald L. (Inventor); Allen, Earl R. (Inventor); Golden, Dadigamuwage C. (Inventor)

    1995-01-01

    A synthetic soil/fertilizer for horticultural application having all the agronutrients essential for plant growth is disclosed. The soil comprises a synthetic apatite fertilizer having sulfur, magnesium and micronutrients dispersed in a calcium phosphate matrix, a zeolite cation exchange medium saturated with a charge of potassium and nitrogen cations, and an optional pH buffer. Moisture dissolves the apatite and mobilizes the nutrient elements from the apatite matrix and the zeolite charge sites.

  12. Biological degradation of TNT-contaminated soil

    SciTech Connect

    Manning, J.F.; Boopathy, R. [Argonne National Lab., IL (United States)

    1995-12-31

    The concept of using biological slurry reactors to remediate soil contaminated with TNT has been investigated at the laboratory scale. Important parameters include an organic co-substrate and appropriate amounts of nitrogen and phosphorus added as nutrients. Normally, the degradation requires an organic co-substrate. The type of co-substrate can have a significant impact on the rate and extent of degradation. Succinate, malate, molasses, and glucose are all acceptable co-substrates. Molasses, or succinate with added yeast extract and/or peptone, provides superior rates of removal. Consortia of microorganisms isolated from various sites can also degrade TNT. To exploit the microbial system, laboratory scale soil slurry reactors have been operated, achieving reductions in TNT concentrations on the order of 90-99% from initial TNT concentrations of 7,000-10,000 mg/kg. Laboratory scale tests have shown that all of the intermediates can be removed by microbial degradation. Laboratory reactors operated with 15% volume replacement one, two, or three times a week achieved removal of 95-99% of the TNT in the feed soil. This system can reduce TNT concentrations to less than 20 mg/kg in treated soil. In particular, operation of the reactors in an aerobic-anoxic sequenced pattern promotes the conversion of TNT to CO{sub 2} and microbial biomass. Radiolabeling studies demonstrated that 50% of the TNT is mineralized, with 30% of the original labeled TNT being converted to microbial biomass. To take advantage of this technology, a field demonstration in which the soil slurry reactor is being used to degrade explosives-contaminated soil is currently being conducted.

  13. Biological Chlorine Cycling in Arctic Peat Soils

    NASA Astrophysics Data System (ADS)

    Zlamal, J. E.; Raab, T. K.; Lipson, D.

    2014-12-01

    Soils of the Arctic tundra near Barrow, Alaska are waterlogged and anoxic throughout most of the profile due to underlying permafrost. Microbial communities in these soils are adapted for the dominant anaerobic conditions and are capable of a surprising diversity of metabolic pathways. Anaerobic respiration in this environment warrants further study, particularly in the realm of electron cycling involving chlorine, which preliminary data suggest may play an important role in arctic anaerobic soil respiration. For decades, Cl was rarely studied outside of the context of solvent-contaminated sites due to the widely held belief that it is an inert element. However, Cl has increasingly become recognized as a metabolic player in microbial communities and soil cycling processes. Organic chlorinated compounds (Clorg) can be made by various organisms and used metabolically by others, such as serving as electron acceptors for microbes performing organohalide respiration. Sequencing our arctic soil samples has uncovered multiple genera of microorganisms capable of participating in many Cl-cycling processes including organohalide respiration, chlorinated hydrocarbon degradation, and perchlorate reduction. Metagenomic analysis of these soils has revealed genes for key enzymes of Cl-related metabolic processes such as dehalogenases and haloperoxidases, and close matches to genomes of known organohalide respiring microorganisms from the Dehalococcoides, Dechloromonas, Carboxydothermus, and Anaeromyxobacter genera. A TOX-100 Chlorine Analyzer was used to quantify total Cl in arctic soils, and these data were examined further to separate levels of inorganic Cl compounds and Clorg. Levels of Clorg increased with soil organic matter content, although total Cl levels lack this trend. X-ray Absorption Near Edge Structure (XANES) was used to provide information on the structure of Clorg in arctic soils, showing great diversity with Cl bound to both aromatic and alkyl groups. Incubations were conducted in the laboratory providing arctic soils with Clorg, and measurements taken to assess rates of organohalide respiration show an increase in chloride production due to microbial activity. Investigating these soils with diverse techniques affirms the importance of Cl-cycling in a pristine arctic tundra ecosystem.

  14. METHOD FOR SCALING BIOLOGICAL RESPONSE OF SOIL MICROCOSMS

    EPA Science Inventory

    An extensive series of laboratory experiments was conducted in soil microcosms to study the respiratory response of microorganisms to toxicant amendments within different types of soils. Our analysis of test results demonstrates that coupled biological and environmental factors w...

  15. Influence of chlorothalonil on soil enzyme activity

    Microsoft Academic Search

    Lei Yan; Li-yuan Hou; Yu Bai; Bi-ying Li; Xiu-yan Zhou; Zhi-wei Qin

    2011-01-01

    In this paper, we studied the influence of different concentrations of chlorothalonil which was commonly used in North China, on the activities of soil invertase, catalase and urease. The results showed that the influence trend of chlorothalonil at different doses on soil enzyme activity was almost the same. For soil catalase, it showed significant activation. For soil urease, it showed

  16. Soil disturbance increases soil microbial enzymatic activity in arid ecoregion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional diversity of the soil microbial community is commonly used in the assessment of soil health as it relates to the activity of soil microflora involved in carbon cycling. Soil microbes in different microenvironments will have varying responses to different substrates, thus catabolic fingerp...

  17. Fertilization regimes affect the soil biological characteristics of a sudangrass and ryegrass rotation system.

    PubMed

    Li, WenXi; Lu, JianWei; Li, FangBai; Wang, Yan; Lu, JunMing; Li, XiaoKun

    2011-06-01

    The sudangrass (Sorghum sudanense) and ryegrass (Lolium multiflorum L.) rotation is an intensive and new cropping system in Central China. Nutrient management practices in this rotation system may influence soil fertility, the important aspects of which are soil biological properties and quality. As sensitive soil biological properties and quality indicators, soil microbial community activity, microbial biomass, enzyme activities, soil organic matter (SOM) and total N resulting from different fertilization regimes in this rotation system were studied through a four-year field experiment from April 2005 to May 2009. Treatments included control (CK), fertilizer phosphorus and potassium (PK), fertilizer nitrogen and potassium (NK), fertilizer nitrogen and phosphorus (NP) and a fertilizer nitrogen, phosphorus and potassium combination (NPK). Soil microbial community activities in the NK, NP and NPK treatments were significantly lower than those in the CK and PK treatments after the sudangrass and ryegrass trial. The highest microbial biomass C, microbial biomass N, SOM, total N, sucrase and urease activities were found in the NPK treatment, and these soil quality indicators were significantly higher in the NK, NP and NPK treatments than in the PK and CK treatments. Soil microbial biomass and enzyme activities were positively associated with SOM in the sudangrass and ryegrass rotation system, indicating that fertilization regimes, especially N application, reduced microbial community activity in the soil. Proper fertilization regimes will increase microbial biomass, enzyme activity and SOM and improve soil fertility. PMID:21706419

  18. Effects of amendment of different biochars on soil physical and biological properties related to carbon mineralization

    NASA Astrophysics Data System (ADS)

    Zhang, Renduo; Zhu, Shuzhi; Ouyang, Lei

    2014-05-01

    Biochar addition to soils potentially affects various soil properties, and these effects are dependent on biochars derived from different feedstock materials and pyrolysis processes. The objective of this study was to investigate the effects of amendment of different biochars on soil physical and biological properties. Biochars were produced with dairy manure and woodchip at temperatures of 300, 500, and 700°C, respectively. Each biochar was mixed at 5% (w/w) with a forest soil and the mixture was incubated for 180 days, during which soil physical and biological properties, and soil respiration rates were measured. Results showed that the biochar addition significantly enhanced the formation of soil macroaggregates at the early incubation time. The biochar application significantly reduced soil bulk density, increased the amount of soil organic matter, and stimulated microbial activity and soil respiration rates at the early incubation stage. Biochar applications improved water retention capacity, with stronger effects by biochars produced at higher pyrolysis temperatures. At the same suction, the soil with woodchip biochars possessed higher water content than with the dairy manure biochars. Biochar addition significantly affected the soil physical and biological properties, which resulted in different soil carbon mineralization rates.

  19. Evaporative losses from soils covered by physical and different types of biological soil crusts

    USGS Publications Warehouse

    Chamizo, S.; Cantón, Y.; Domingo, F.; Belnap, J.

    2013-01-01

    Evaporation of soil moisture is one of the most important processes affecting water availability in semiarid ecosystems. Biological soil crusts, which are widely distributed ground cover in these ecosystems, play a recognized role on water processes. Where they roughen surfaces, water residence time and thus infiltration can be greatly enhanced, whereas their ability to clog soil pores or cap the soil surface when wetted can greatly decrease infiltration rate, thus affecting evaporative losses. In this work, we compared evaporation in soils covered by physical crusts, biological crusts in different developmental stages and in the soils underlying the different biological crust types. Our results show that during the time of the highest evaporation (Day 1), there was no difference among any of the crust types or the soils underlying them. On Day 2, when soil moisture was moderately low (11%), evaporation was slightly higher in well-developed biological soil crusts than in physical or poorly developed biological soil crusts. However, crust removal did not cause significant changes in evaporation compared with the respective soil crust type. These results suggest that the small differences we observed in evaporation among crust types could be caused by differences in the properties of the soil underneath the biological crusts. At low soil moisture (<6%), there was no difference in evaporation among crust types or the underlying soils. Water loss for the complete evaporative cycle (from saturation to dry soil) was similar in both crusted and scraped soils. Therefore, we conclude that for the specific crust and soil types tested, the presence or the type of biological soil crust did not greatly modify evaporation with respect to physical crusts or scraped soils.

  20. Exchange of greenhouse gases between soil and atmosphere: interactions of soil physical factors and biological processes

    Microsoft Academic Search

    K. A. S MITH; F. C ONEN; K. E. D OBBIE; A. R EY

    2003-01-01

    Summary This review examines the interactions between soil physical factors and the biological processes respon- sible for the production and consumption in soils of greenhouse gases. The release of CO2 by aerobic respiration is a non-linear function of temperature over a wide range of soil water contents, but becomes a function of water content as a soil dries out. Some

  1. Application Sequence and soil biology influence anaerobic soil disinfestation induced disease suppression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaerobic soil disinfestation (ASD) and mustard seed meal (MSM) soil amendments can yield significant control of a diversity of soil-borne pests and pathogens. The mechanisms functional in disease suppression are diverse and with regard to MSM amendment, soil biology has been shown to have a signif...

  2. Soil Biology & Biochemistry 38 (2006) 22052211 Glomalin-related soil protein: Assessment of current detection

    E-print Network

    Rilli, Matthias C.

    2006-01-01

    identification resting solely on the methods used to extract it from soil (citric acid buffer and autoclaving. In two studies we spiked soil samples either with known quantities of a glycoprotein (BSA: bovine serumSoil Biology & Biochemistry 38 (2006) 2205­2211 Glomalin-related soil protein: Assessment

  3. Biological activities of 7-epiclusianone.

    PubMed

    Alves, T M; Alves, R; Romanha, A J; Zani, C L; dos Santos, M H; Nagem, T J

    1999-02-01

    7-Epiclusianone, isolated from Rheedia gardneriana, was tested in several biological assays. It was active in vitro against trypomastigotes of Trypanosoma cruzi but inactive in vivo in experimentally infected mice. It was also active against Artemia salina, but inactive against the fungus Cladosporium sphaerospermum and the snail Biomphalaria glabrata. PMID:10075791

  4. Effects of Cd and Pb on soil microbial community structure and activities

    Microsoft Academic Search

    Sardar Khan; Abd El-Latif Hesham; Min Qiao; Shafiqur Rehman; Ji-Zheng He

    2010-01-01

    Background, aim, and scope  Soil contamination with heavy metals occurs as a result of both anthropogenic and natural activities. Heavy metals could have\\u000a long-term hazardous impacts on the health of soil ecosystems and adverse influences on soil biological processes. Soil enzymatic\\u000a activities are recognized as sensors towards any natural and anthropogenic disturbance occurring in the soil ecosystem. Similarly,\\u000a microbial biomass carbon

  5. Biological activities of carrageenan.

    PubMed

    Pangestuti, Ratih; Kim, Se-Kwon

    2014-01-01

    Red seaweeds are popular and economically important worldwide and also well known for their medicinal effects due to the presence of phycocolloids. Carrageenans, the major phycocolloid group of red algae, have been extensively investigated for their vast array of bioactivities such as anticoagulant, antiviral, cholesterol-lowering effects, immunomodulatory activity, and antioxidant. Carrageenan possesses promising activity both in vitro and in vivo, showing promising potential to be developed as therapeutic agents. In this chapter, attempts have been made to examine the health benefit effects of carrageenans. PMID:25081080

  6. Biological and biochemical soil indicators: monitoring tools of different agricultural managements

    NASA Astrophysics Data System (ADS)

    Scotti, Riccardo; Sultana, Salma; Scelza, Rosalia; Marzaioli, Rossana; D'Ascoli, Rosaria; Rao, Maria A.

    2010-05-01

    The intensive agricultural managements, increased in the last twenty years, have resulted in a decrease in fertility of soils, representing a serious threat to agricultural productivity due to both the increase in production cost, mainly for intensive use of mineral fertilizers, and the loss of the quality of crops themselves. Organic matter content is closely related to the soil fertility and its progressive reduction in cultivates soils, without a satisfactory recovery, could make agriculture untenable, resulting in a high detrimental effect on environment. But an appropriate soil management practices can improve soil quality by utilizing organic amendments as alternative to mineral fertilizers to increase soil quality and plant growth. In this context, demand of suitable indicators, whose are able to assess the impact of different agricultural managements on soil quality, has increased. It has shown that soil biological and biochemical properties are able to respond to small changes in soil conditions, thus providing information on subtle alterations in soil quality. Aim of this study was to evaluate the use of soil biological and biochemical properties as fertility indicators in agricultural soils under different agricultural managements, sited in Campania Region (Southern Italy). After a preliminary monitoring phase of soil fertility on different farms sited in five agricultural areas of Campania Region, we have selected two farms in two different study areas to assess the effect on soil quality of different organic amendments. In particular, a compost from municipal solid waste and wood from scraps of poplars pruning were supplied in different doses and ratios. Soil samplings after one month from the amendment addition and then every 4 months until a year were carried out. All collected soil samples were characterized by main physical, chemical, biochemical and biological properties. In general, the use of different organic amendments showed a positive effect on fertility of both soils under intensive farming. In general, all enzymatic activities and organic carbon content increased after 1 month, and they were still higher after 4 months from amendment application. Microbial biomass and soil potential activity (respiration) showed significantly higher values in soils added with organic amendments, for both farms and samplings, with more marked effects on respiration in the first sampling. In conclusion results showed, in general, a quick response as indicators of the assayed biological and biochemical soil properties and a good recovery in fertility of the studied agricultural soils. The project was founded by CCIIAA of Salerno

  7. Response of soil microbial activity and biodiversity in soils polluted with different concentrations of cypermethrin insecticide.

    PubMed

    Tejada, Manuel; García, Carlos; Hernández, Teresa; Gómez, Isidoro

    2015-07-01

    We performed a laboratory study into the effect of cypermethrin insecticide applied to different concentrations on biological properties in two soils [Typic Xerofluvent (soil A) and Xerollic Calciorthid (soil B)]. Two kg of each soil were polluted with cypermethrin at a rate of 60, 300, 600, and 1,200 g ha(-1) (C1, C2, C3, and C4 treatments). A nonpolluted soil was used as a control (C0 treatment). For all treatments and each experimental soil, soil dehydrogenase, urease, ?-glucosidase, phosphatase, and arylsulphatase activities and soil microbial community were analysed by phospholipid fatty acids, which were measured at six incubation times (3, 7, 15, 30, 60, and 90 days). The behavior of the enzymatic activities and microbial population were dependent on the dose of insecticide applied to the soil. Compared with the C0 treatment, in soil A, the maximum inhibition of the enzymatic activities was at 15, 30, 45, and 90 days for the C1, C2, C3, and C4 treatments, respectively. However, in soil B, the maximum inhibition occurred at 7, 15, 30, and 45 days for the C1, C2, C3, and C4 treatments, respectively. These results suggest that the cypermethrin insecticide caused a negative effect on soil enzymatic activities and microbial diversity. This negative impact was greater when a greater dose of insecticide was used; this impact was also greater in soil with lower organic matter content. For both soils, and from these respective days onward, the enzymatic activities and microbial populations progressively increased by the end of the experimental period. This is possibly due to the fact that the insecticide or its breakdown products and killed microbial cells, subsequently killed by the insecticide, are being used as a source of energy or as a carbon source for the surviving microorganisms for cell proliferation. PMID:25604921

  8. Rich in life but poor in data: the known knowns and known unknowns of modelling how soil biology drives soil structure

    NASA Astrophysics Data System (ADS)

    Hallett, Paul; Ogden, Mike

    2015-04-01

    Soil biology has a fascinating capacity to manipulate pore structure by altering or overcoming hydrological and mechanical properties of soil. Many have postulated, quite rightly, that this capacity of soil biology to 'engineer' its habitat drives its diversity, improves competitiveness and increases resilience to external stresses. A large body of observational research has quantified pore structure evolution accompanied by the growth of organisms in soil. Specific compounds that are exuded by organisms or the biological structures they create have been isolated and found to correlate well with observed changes to pore structure or soil stability. This presentation will provide an overview of basic mechanical and hydrological properties of soil that are affected by biology, and consider missing data that are essential to model how they impact soil structure evolution. Major knowledge gaps that prevent progress will be identified and suggestions will be made of how research in this area should progress. We call for more research to gain a process based understanding of structure formation by biology, to complement observational studies of soil structure before and after imposed biological activity. Significant advancement has already been made in modelling soil stabilisation by plant roots, by combining data on root biomechanics, root-soil interactions and soil mechanical properties. Approaches for this work were developed from earlier materials science and geotechnical engineering research, and the same ethos should be adopted to model the impacts of other biological compounds. Fungal hyphae likely reinforce soils in a similar way to plant roots, with successful biomechanical measurements of these micron diameter structures achieved with micromechanical test frames. Extending root reinforcement models to fungi would not be a straightforward exercise, however, as interparticle bonding and changes to pore water caused by fungal exudates could have a major impact on structure formation and stability. Biological exudates from fungi, bacteria or roots have been found to decrease surface tension and increase viscosity of pore water, with observed impacts to soil strength and water retention. Modelling approaches developed in granular mechanics and geotechnical engineering could be built upon to incorporate biological transformations of hydrological and mechanical properties of soil. With new testing approaches, adapted from materials science, pore scale hydromechanical impacts from biological exudates can be quantified. The research can be complemented with model organisms with differences in biological structures (e.g. root hair mutants), exudation or other properties. Coupled with technological advances that provide 4D imaging of soil structure at relatively rapid capture rates, the potential opportunities to disentangle and model how biology drives soil structure evolution and stability are vast. By quantifying basic soil hydrological and mechanical processes that are driven by soil biology, unknown unknowns may also emerge, providing new insight into how soils function.

  9. Molecular Biology Concepts and Activities

    NSDL National Science Digital Library

    Ingrid Waldron

    This overview reviews key concepts and learning activities to help students understand how genes influence our traits by molecular processes. Topics covered include basic understanding of the important roles of proteins and DNA; DNA structure, function and replication; the molecular biology of how genes influence traits, including transcription and translation; and the molecular biology of mutations. To help students understand the relevance of these molecular processes, the suggested learning activities link alleles of specific genes to human characteristics such as albinism, sickle cell anemia and muscular dystrophy. This overview provides links to suggested activities which include hands-on laboratory and simulation activities, web-based simulations, discussion activities and a vocabulary review game.

  10. [Spectral characteristics of biological soil crusts in Gurbantonggut Desert, Xinjiang].

    PubMed

    Chen, Jin; Yang, Wei; Zhang, Yuan-Ming; Wang, Xue-Qin

    2008-01-01

    Large areas of desert in arid and semi-arid regions are covered by biological soil crusts. Tracking the presence, distribution and disappearance of biological soil crusts is important for ecosystem management of desert regions and provides highly valuable information about desertification and climate change studies in arid and semiarid environments. The objective of the present paper is to analyze the unique reflectance spectral features of three types of biological soil crusts (moss, lichen and algae) relative to bare sand and dry plant. The measurements for the reflectance of bare sand, dry plant and biological soil crusts derived from the field survey were performed in the laboratory under dry condition. The reflectance of biological soil crusts after they were hydrated with 0.5 and 1.0 mm water respectively was also measured in the laboratory. It was found that the reflectance of crusts was much lower than that of bare sand throughout the Vis-SWIR region. Moreover, the reflectance of crusts exhibited a slightly flattening plateau between 600 and 750 nm, attributed to the absorption of photosynthetic pigments. Based on the spectral features of biological soil crusts, it was proposed that continuum removal technique could be used to retrieve the coverage of biological soil crusts. A significant correlation between the minus logarithm of the absorption depth of the continuum removal spectra and the coverage of biological soil crusts was found (r2 = 0.990 7). The liquid-water hydration experiment demonstrated that the absorption of photosynthetic pigments was strengthened after hydration, making the detection of biological soil crusts much easier. PMID:18422113

  11. Estimating active carbon for soil quality assessment: A simplified method for laboratory and field use

    Microsoft Academic Search

    K. R. Islam; M. A. Stine; J. B. Gruver; S. E. Samson-Liebig; R. R. Weil

    2003-01-01

    A simple method of estimating changes in biologically active soil carbon (C) could help evaluate soil quality impacts of alternative management practices. Most reports of permanganate for active C determination use highly concentrated solutions (0.333 M) that are difficult to work with and tend to react with a large fraction of soil C that is not well distinguished from total

  12. Wildfire effects on biological properties of soils in forest-steppe ecosystems of Russia

    NASA Astrophysics Data System (ADS)

    Maksimova, E.; Abakumov, E.

    2014-01-01

    Soils affected by forest wildfires in 2010 in Russia were studied on postfire and mature plots near the Togljatty city, Samara region. Soil biological properties and ash composition dynamics were investigated under the forest fire affect: a place of local forest fire, riding forest fire and unaffected site by fire-control (mature) during 3 yr of restoration. Soil samples were collected at 0-15 cm. Soil biological properties was measured by the fumigation method. The analytical data obtained shows that wildfires lead to serious changes in a soil profile and soil chemistry of upper horizons. Wildfires change a chemical composition of soil horizons and increase their ash-content. Fires lead to accumulation of biogenic elements' content (P and K) in the solum fine earth. Calcium content is increased as a result of fires that leads to an alkaline pH of the solum. The values of nutrients decreased as a result of leaching out with an atmospheric precipitation during the second year of restoration. Thus, when the upper horizons are burning the ash arriving on a soil surface enrich it with nutrients. The mature (unaffected by fire) soils is characterized by the greatest values of soil microbial biomass in the top horizon and, respectively, the bigger values of basal respiration whereas declining of the both parameters was revealed on postfire soils. Nevertheless this influence does not extend on depth more than 10 cm. Thus, fire affect on the soil were recognized in decreasing of microbiological activity.

  13. The influence of carbonates in parent rocks on the biological properties of mountain soils of the Northwest Caucasus region

    NASA Astrophysics Data System (ADS)

    Kazeev, K. Sh.; Kutrovskii, M. A.; Dadenko, E. V.; Vezdeneeva, L. S.; Kolesnikov, S. I.; Val'kov, V. F.

    2012-03-01

    The biological activity of different subtypes of soddy-calcareous soils (rendzinas) of the Northwest Caucasus region was studied. In the Novorossiisk-Abrau-Dyurso region (dry subtropics), typical soddy-calcareous soils with the high content of carbonates predominate; in the more humid conditions of the Lagonaki Plateau (Republic of Adygeya), leached soddy-calcareous soils carbonate-free down to the parent rock are spread. The number of microarthropods, the populations of fungi and bacteria, and the enzyme activity (catalase, dehydrogenase, and invertase) testify that the biological activity of these soils significantly differs. In the typical soddy-calcareous soils of the dry subtropics, the content of carbonates does not affect the characteristics mentioned; in the more humid conditions of the West Caucasus region, the presence of carbonates in the parent rocks intensifies the biological activity of the soddy-calcareous soils.

  14. Biological activities of Annona glabra.

    PubMed

    Padmaja, V; Thankamany, V; Hara, N; Fujimoto, Y; Hisham, A

    1995-08-11

    On a preliminary screening, substantial antimicrobial, antifungal and moderate insecticidal, sporicidal and cytotoxic activities were observed for the hexane extract of the stem bark of Amona glabra L. Chromatographic fractionation of this extract led to the isolation of kaur-16-en-19-oic acid in a large amount as the main constituent, which was found to be largely responsible for the biological activities possessed by the crude extract. PMID:8569243

  15. Effects of perchloroethylene soil pollution on soil enzyme activities

    Microsoft Academic Search

    Aiqin Shan; Aikuan Wang; Jing Cai; Li Haihua; Honglin Tao

    2011-01-01

    Simulated experiments were conducted to study the eco-toxicology effects of perchloroethylene (PCE) pollutant on three main soil enzyme activities: protease, urease and catalase. The results showed that, increasing the initial PCE concentration resulted in higher inhibition effect on both protease and urease activities. The process was inhibited firstly and then recovered. PCE had a significant inhibition effect on soil protease

  16. Investigation of Biological Soil Crusts Metabolic Webs Using Exometabolomic Analysis

    NASA Astrophysics Data System (ADS)

    Northen, T.; Karaoz, U.; Jenkins, S.; Lau, R.; Bowen, B.; Cadillo-Quiroz, H.; Garcia-Pichel, F.; Brodie, E.; Richard, B.

    2014-12-01

    Desert biological soil crusts are simple cyanobacteria-dominated surface soil microbial communities found in areas with infrequent wetting, often extreme temperatures, low coverage of vascular plants and constitute the world's largest biofilm. They exist for extended periods in a desiccated dormant state, yet rapidly re-boot metabolism within minutes of wetting. These soil microbial communities are highly dependent on filamentous cyanobacteria such as Microcoleus vaginatusto stabilize the soil and to act as primary producers for the community through the release carbon sources to feed a diversity of heterotrophs. Exometabolomic analysis was performed using liquid chromatography coupled to tandem mass spectrometry on biological soil crust pore water and spent media of key soil bacterial isolates. Comparison of spent vs. fresh media was used to determine uptake or release of metabolites by specific microbes. To link pore water experiments with isolate studies, metabolite extracts of authentic soil were used as supplements for isolate exometabolomic profiling. Our soil metabolomics methods detected hundreds of metabolites from soils including may novel compounds. Only a small set of which being targeted by all isolates. Beyond these few metabolites, the individual bacteria examined showed specialization towards specific metabolites. Surprisingly, many of the most abundant oligosaccharides and other metabolites were ignored by these isolates. The observed specialization of biological soil crust bacteria may play a significant role in determining community structure.

  17. Mind the gap: non-biological processes contributing to soil CO2 efflux.

    PubMed

    Rey, Ana

    2015-05-01

    Widespread recognition of the importance of soil CO2 efflux as a major source of CO2 to the atmosphere has led to active research. A large soil respiration database and recent reviews have compiled data, methods, and current challenges. This study highlights some deficiencies for a proper understanding of soil CO2 efflux focusing on processes of soil CO2 production and transport that have not received enough attention in the current soil respiration literature. It has mostly been assumed that soil CO2 efflux is the result of biological processes (i.e. soil respiration), but recent studies demonstrate that pedochemical and geological processes, such as geothermal and volcanic CO2 degassing, are potentially important in some areas. Besides the microbial decomposition of litter, solar radiation is responsible for photodegradation or photochemical degradation of litter. Diffusion is considered to be the main mechanism of CO2 transport in the soil, but changes in atmospheric pressure and thermal convection may also be important mechanisms driving soil CO2 efflux greater than diffusion under certain conditions. Lateral fluxes of carbon as dissolved organic and inorganic carbon occur and may cause an underestimation of soil CO2 efflux. Traditionally soil CO2 efflux has been measured with accumulation chambers assuming that the main transport mechanism is diffusion. New techniques are available such as improved automated chambers, CO2 concentration profiles and isotopic techniques that may help to elucidate the sources of carbon from soils. We need to develop specific and standardized methods for different CO2 sources to quantify this flux on a global scale. Biogeochemical models should include biological and non-biological CO2 production processes before we can predict the response of soil CO2 efflux to climate change. Improving our understanding of the processes involved in soil CO2 efflux should be a research priority given the importance of this flux in the global carbon budget. PMID:25471988

  18. Diverse biological activities of dandelion.

    PubMed

    González-Castejón, Marta; Visioli, Francesco; Rodriguez-Casado, Arantxa

    2012-09-01

    Dandelion (Taraxacum officinale Weber) is a member of the Asteraceae (Compositae) family, native to Europe but widely distributed in the warmer temperate zones of the Northern Hemisphere. Dandelion and its parts are habitually consumed as plant foods in several areas of the world, where they are also employed in phytotherapy. Indeed, dandelion contains a wide array of phytochemicals whose biological activities are actively being explored in various areas of human health. In particular, emerging evidence suggests that dandelion and its constituents have antioxidant and anti-inflammatory activities that result in diverse biological effects. The present review provides a comprehensive analysis of the constituents of dandelion, an assessment of the pharmacological properties of dandelion, and a description of relevant studies that support the use of dandelion as a medicinal plant. PMID:22946853

  19. Reconciling apparent variability in effects of biochar amendment on soil enzyme activities by assay optimization

    Microsoft Academic Search

    Vanessa L. Bailey; Sarah J. Fansler; Jeffrey L. Smith; Harvey Bolton

    2011-01-01

    We studied the effects of a biochar made from fast pyrolysis of switchgrass on four soil enzymes (?-glucosidase, ?-N-acetylglucosaminidase, lipase, and leucine aminopeptidase) to determine if biochar would consistently modify soil biological activities. Thus, we conducted a series of enzyme assays on biochar-amended soils. Inconsistent results from enzyme assays of char-amended soils suggested that biochar had variable effects on soil

  20. Effects of biological weathering on mine soil genesis and fertility

    SciTech Connect

    Everett, C.J.

    1981-01-01

    Strip mine spoils derived from overburden rocks of the Pennsylvanian Wise Formation in Buchanan County, Virginia, commonly contain 40% less than 2 mm sized soil material. The physical and chemical properties of these soil materials are related to their rock origin. The soil materials are alkaline due to the presence of carbonates. The principal source of P in the soil materials is apatite, and the principal source of K is mica. A greenhouse experiment was conducted to determine the short-term plant availability of P and K in these soil materials. Growth of sericea lespedeza over a 60-day period was found to be limited by P availability and not to be limited by K availability. Uptake of P by servicea lespedeza from P fertilized and unfertilized soil materials was found to be correlated with NaHCO3 extractable P from pots which received the same fertilizer treatments but did not contain plants. The correlations obtained were soil material specific. A separate greenhouse experiment was conducted in order to identify the effects of biological weathering on soil material properties. Sericea lespedeza and black locust were grown on unfertilized brown sandstone soil material for one year. Soil material pH was uniformly reduced by plant action regardless of proximity to roots. The P present in the soil material, however, was not uniformly depleted. Over half of the P removed from the soil material by sericea lespedeza and black locust was P which cannot be extracted using dilute HCl-H2SO4, but can be extracted using concentrated HCl. The results of the two experiments indicate that the plant availability of P and K in the soil materials is influenced by biological weathering. Acidification of the soil material increases the availability of P present in apatite particles. Uptake of K insures that the soil solution is constantly replenished with K from mica and that mica is transformed into vermiculite.

  1. Biological Dimensions of Crack Morphology in Dryland Soils

    NASA Astrophysics Data System (ADS)

    DeCarlo, K. F.; Spiegel, M.; Caylor, K. K.

    2014-12-01

    Macropores and cracks have an integral role in soil hydrology, and the physicochemical factors that induce them have been the subject of much laboratory research. How these processes translate to field soils, however, is often obfuscated by the biological elements present that complicate its formation and dynamics. In this study, we investigated the biological influence of herbivores and vegetation on 3D crack morphology in a dryland swelling soil (black cotton/vertisol). Fieldwork was conducted at and near the Kenya Long-Term Exclosure Experiment (KLEE) plots in Mpala, central Kenya, where three different soil regions were identified: highly vegetated areas, animal trails, and termite mounds. Crack networks were physically characterized by pouring liquid resin into the soil and excavating them when dry, after which they were imaged and quantified using medical magnetic resonance imaging (MRI). Cracking intensity of each cast was corrected via soil moisture and bulk density measurements at 5 cm intervals over 30 cm. 3D characterization of the soil system shows that mechanical compaction is a major influence in the formation of extensive and deep cracks in animal trails, with megaherbivores (e.g. elephants) inducing the most extreme cracks. Bioturbation is seen as a major influence in the formation of shallower cracks in termite mounds, as termites loosen and aerate the soil and reduce the soil's cohesive properties. Highly vegetated soils show a large degree of variability: small, disconnected soil patches induced by vegetative cover and a larger root network results in smaller and shallower cracks, but full vegetative cover induces deep and irregular cracks, possibly due to diverted rainfall. Our results highlight the intricate connections between the biology and physics that dictate soil processes in a complex soil system at the field scale.

  2. Neutron-Activation Soil Analysis in Ecological Investigations

    Microsoft Academic Search

    Sh. Khatamov; A. Zhumamuratov; B. Ibragimov; T. Tillaev

    2000-01-01

    The scientific-technical base and instrumentation for neutron-activation analysis has reached a level such that today such an analysis can be used to find more than 70 chemical elements in soil and other biological objects. The method is widely used in various fields of science and industry. At the same time, as noted in [1], unsolved methodological and metrological problems are

  3. Phenol removal by soil adsorption with activated sludge addition

    SciTech Connect

    Yungtse Hung (Cleveland State Univ., OH (United States)); Lo, H.H.

    1993-11-01

    This research study evaluated the removal of phenol by using different types of soils and soils plus activated sludge. Treatment time intervals were one, two, three, five and seven days. Four types of soils--loam, sandy loam, silty loam, and silty-clay loam--were collected from the metropolitan Cleveland area and were used in the study. The soil to wastewater ratios of 1:1, 1:2 and 1:5 were used in the treatment experiment. Activated sludge of various concentrations was added in soils to improve treatment efficiency. Results showed that the loam, silty loam and silty-clay appeared to be effective in reducing phenol levels over the given soil/wastewater ratios and designated treatment time intervals. The phenol removal efficiency ranged from 30 percent to 55 percent. Among the four types of soils which have been added with activated sludge, the silty loam and silty-clay loam proved to be most effective in removing phenol from wastewater with a phenol removal efficiency up to 70 percent. It was also found that addition of activated sludge to the soil enhanced biological oxidation and removal of phenol.

  4. The Soil Moisture Active Passive (SMAP) Mission

    Microsoft Academic Search

    Dara Entekhabi; Eni G. Njoku; Peggy E. O'Neill; Kent H. Kellogg; Wade T. Crow; Wendy N. Edelstein; Jared K. Entin; Shawn D. Goodman; Thomas J. Jackson; Joel Johnson; John Kimball; Jeffrey R. Piepmeier; Randal D. Koster; Neil Martin; Kyle C. McDonald; Mahta Moghaddam; Susan Moran; Rolf Reichle; J. C. Shi; Michael W. Spencer; Samuel W. Thurman; Leung Tsang; Jakob Van Zyl

    2010-01-01

    The Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey. SMAP will make global measurements of the soil moisture present at the Earth's land surface and will distinguish frozen from thawed land surfaces. Direct observations of soil moisture and freeze\\/thaw state from

  5. Reconciling apparent variability in effects of biochar amendment on soil enzyme activities by assay optimization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We studied the effects of a biochar made from switchgrass on four soil enzymes (ß- glucosidase, ß-N-acetylglucosaminidase, lipase, and leucine aminopeptidase) to determine if biochar would consistently modify soil biological activities. Inconsistent results from enzyme assays of char-amended soils s...

  6. Ice nucleation activity in the widespread soil fungus Mortierella alpina

    NASA Astrophysics Data System (ADS)

    Fröhlich-Nowoisky, J.; Hill, T. C. J.; Pummer, B. G.; Yordanova, P.; Franc, G. D.; Pöschl, U.

    2015-02-01

    Biological residues in soil dust are a potentially strong source of atmospheric ice nuclei (IN). So far, however, the abundance, diversity, sources, seasonality, and role of biological - in particular, fungal - IN in soil dust have not been characterized. By analysis of the culturable fungi in topsoils, from a range of different land use and ecosystem types in southeast Wyoming, we found ice-nucleation-active (INA) fungi to be both widespread and abundant, particularly in soils with recent inputs of decomposable organic matter. Across all investigated soils, 8% of fungal isolates were INA. All INA isolates initiated freezing at -5 to -6 °C, and belonged to a single zygomycotic species, Mortierella alpina (Mortierellales, Mortierellomycotina). To our knowledge this is the first report of ice nucleation activity in a zygomycotic fungi because the few known INA fungi all belong to the phyla Ascomycota and Basidiomycota. M. alpina is known to be saprobic and widespread in soil, and Mortierella spores are present in air and rain. Sequencing of the ITS region and the gene for ?-linolenic elongase revealed four distinct clades, affiliated to different soil types. The IN produced by M. alpina seem to be proteinaceous, < 300 kDa in size, and can be easily washed off the mycelium. Ice nucleating fungal mycelium will ramify topsoils and probably also release cell-free IN into it. If these IN survive decomposition or are adsorbed onto mineral surfaces, their contribution might accumulate over time, perhaps to be transported with soil dust and influencing its ice nucleating properties.

  7. EFFECTS OF A BIOLOGICAL AMENDMENT ON CHEMICAL AND BIOLOGICAL PROPERTIES AND MICROBIAL DIVERSITY IN SOILS RECEIVING DIFFERENT ORGANIC AMENDMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biological fertilizers consisting of suspensions of selected microorganisms are often used in conjunction with various organic materials for amending soils to improve soil quality and plant growth. The effects of a biological fertilizer on chemical and biological properties of soil were investigated...

  8. Nitrogen Fixation and Leaching of Biological Soil Crust Communities in Mesic Temperate Soils

    E-print Network

    Neher, Deborah A.

    Microbial Ecology Nitrogen Fixation and Leaching of Biological Soil Crust Communities in Mesic, and fungi. Although crusts are a dominant source of nitrogen (N) in arid ecosystems, this study is among

  9. Variations of soil enzyme activities in a temperate forest soil

    Microsoft Academic Search

    Hojeong Kang; Sinkyu Kang; Dowon Lee

    2009-01-01

    Soil enzyme activities (dehydrogenase, urease, phosphatase, and arylsulfatase) in a temperate forest soil were determined\\u000a in relation to landscape position and seasons. Overstory of the area is dominated by Quercus mongolica, Kalopanax pictus, Carpicus cordata, and Acer pseudo-sieboldianum. The activities were measured in three patches, namely a north-facing backslope, a ridge, and a south-facing backslope in\\u000a autumn and spring over

  10. Bioaugmentation, Biostimulation, and Biocontrol in Soil Biology

    Microsoft Academic Search

    Ajay Singh; Nagina Parmar; Ramesh C. Kuhad; Owen P. Ward

    \\u000a Soils sustain an immense diversity of prokaryotic and eukaryotic organisms. Microbial functions in ecosystems are as diverse\\u000a as the microbes themselves. Differences in microbial community structures reflect the abilities of microorganisms to respond\\u000a to specific environmental factors and substrates. Microbes adapt to these microhabitats and live together in consortia, interacting\\u000a with each other and with other parts of the soil

  11. Ice Nucleation Activity in the Widespread Soil Fungus Mortierella alpina

    NASA Astrophysics Data System (ADS)

    Fröhlich-Nowoisky, J.; Hill, T. C. J.; Pummer, B. G.; Franc, G. D.; Pöschl, U.

    2014-08-01

    Biological residues in soil dust are a potentially strong source of atmospheric ice nuclei (IN). So far, however, the abundance, diversity, sources, seasonality, and role of biological - in particular, fungal - IN in soil dust have not been characterized. By analysis of the culturable fungi in topsoils, from a range of different land use and ecosystem types in south-east Wyoming, we found ice nucleation active (INA) fungi to be both widespread and abundant, particularly in soils with recent inputs of decomposable organic matter. Across all investigated soils, 8% of fungal isolates were INA. All INA isolates initiated freezing at -5 to -6 °C, and belonged to a single zygomycotic species, Mortierella alpina (Mortierellales, Mortierellomycotina). By contrast, the handful of fungal species so far reported as INA all belong within the Ascomycota or Basidiomycota phyla. M. alpina is known to be saprobic, widespread in soil and present in air and rain. Sequencing of the ITS region and the gene for ?-linolenic-elongase revealed four distinct clades, affiliated to different soil types. The IN produced by M. alpina seem to be proteinaceous, <300 kDa in size, and can be easily washed off the mycelium. Ice nucleating fungal mycelium will ramify topsoils and probably also release cell-free IN into it. If these IN survive decomposition or are adsorbed onto mineral surfaces, their contribution might accumulate over time, perhaps to be transported with soil dust and influencing its ice nucleating properties.

  12. Correlations between cryptobiosis and other biological characteristics in some soil animals

    Microsoft Academic Search

    Giovanni Pilato

    1979-01-01

    Attention is focused on soil rotifers, gastrotrichs, nematodes and tardigrades which are active solely when enveloped by a water film and survive freezing and desiccation by virtue of their ability to enter cryptobiosis.All these groups share some morphological and biological characteristics, some of which have a manifest adaptive significance, while in others the adaptive value is less evident. Lastly, some

  13. Molecular characteristics versus biological activity

    USGS Publications Warehouse

    Applegate, Vernon C.; Smith, Manning A.; Willeford, Bennett R.

    1967-01-01

    The molecular characteristics of mononitrophenols containing halogens not only play a key role in their biological activity but provide a novel example of selective toxicity among vertebrate animals. It has been reported that efforts to control the parasitic sea lamprey in the Great Lakes are directed at present to the applications of a selective toxicant to streams inhabited by lamprey larvae. Since 1961, the larvicide that has been used almost exclusively in the control program has been 3-trifluoromethyl-4-nitrophenol (TFM). However, this is only one of about 15 closely related compounds, all halogen-containing mononitrophenols, that display a selectively toxic action upon lampreys. Although not all of the halogenated mononitrophenols are selectively toxic to lampreys (in fact, fewer than half of those tested), no other group of related compounds has displayed any useful larvicidal activity except for the substituted nitrosalicylanilides.

  14. Inhibition of soil urease activity by aminocresols

    Microsoft Academic Search

    G. A. Rodgers

    1984-01-01

    Summary The effect on soil urease activity of five aminocresols, at concentrations of 5–100 ?g\\/g soil, was examined in the laboratory. Two compounds, 4-amino-o-cresol and 4-amino-m-cresol, significantly inhibited urease activity. The efficacy of 4-amino-o-cresol was compared with that of phenylphosphorodiamidate (PPDA), a known inhibitor, in three U.K. soils. At 50?g\\/g soil 4-amino-o-cresol was as inhibitory as an equivalent concentration of

  15. Biological activities of Schefflera leucantha.

    PubMed

    Potduang, Buppachart; Chongsiriroeg, Chanchai; Benmart, Yaowaluck; Giwanon, Rattanasiri; Supatanakul, Winai; Tanpanich, Sayan

    2006-01-01

    This study investigated various biological activities of the ethanolic extract of dried ground leaves of Schefflera leucantha Viguier (Araliaceae). The extract possessed very low cytotoxicity to brine-shrimp with the LC(50) of 4,111.15 microg/ml; the significant antioxidant activity on DPPH with the EC(50) of 71.90 microg/ml; the inhibitory activity on mushroom tyrosinase with the IC(50) of 10.53 mg/ml using the dopachrome microplate-assay. The extract of 5-20 mg/ml range in the agar dilution assay were active against various pathogenic microbial (11 species, 11 strains), with the minimum inhibitory concentration (MIC) of 5 mg/ml against Clostridium spp.; MIC=10 mg/ml against enteropathogens as Bacteroides spp., Enterococcus faecalis ATCC 29212, Lactobacillus spp., Peptococcus spp. and Streptococcus mutans; MIC=10 mg/ml against a pneumonia causing bacteria Klebsiella pneumoniae and a dermatopathogen as Propionibacterium acnes; MIC=20 mg/ml against dermatopathogens as Staphylococcus aureus ATCC 6538, Streptococcus spp. and Candida albicans ATCC 90028. TLC fingerprints of the specific extracts from the leaf powder exhibited zones of steroids-terpenes and flavonoids. HPLC fingerprint of the flavonoid extract was performed. PMID:20162087

  16. Biological indicators capable of assessing thermal treatment efficiency of hydrocarbon mixture-contaminated soil.

    PubMed

    Wang, Jiangang; Zhan, Xinhua; Zhou, Lixiang; Lin, Yusuo

    2010-08-01

    In China, there are many special sites for recycling and washing the used drums, which release a variety of C5-C40 hydrocarbon mixture into the soil around the site. The remediation of these contaminated sites by thermal treatment is adopted ubiquitously and needs to be assessed. Here we report the feasibility of biological indicators applied to assess thermal treatment efficiency in such contaminated soil. A series of biological indicators, including seed germination index (SGI), root elongation index (REI), plant growth height, biomass, carbon dioxide evolved (CDE), soil respiration inhibition (SRI) and soil enzymatic activities, were employed to monitor or assess hydrocarbon mixture removal in thermal treated soil. The results showed that residual hydrocarbon mixture content correlated strongly negatively with SGI for sesamum (Sesamum indicum L.), plant height, and biomass for ryegrass (Lolium perenne L.) in the concentration ranges of 0-3990, 0-3170 and 0-2910 mg kg(-1), respectively. In contrast, REI for sesamum was positively correlated with residual hydrocarbon mixture content from 0 to 1860 mg kg(-1). In addition, both CDE and SRI demonstrated that 600 mg kg(-1) of residual hydrocarbon mixture content caused the highest amount of soil carbon dioxide emission and inhabitation of soil respiration. The results of soil enzymes indicated that 1000 mg kg(-1) of residual hydrocarbon mixture content was the threshold value of stimulating or inhibiting the activities of phosphatase and catalase, or completely destroying the activities of dehydrogenase, invertase, and urease. In conclusion, these biological indicators can be used as a meaningful complementation for traditional chemical content measurement in evaluating the environmental risk of the contaminated sites before and after thermal treatment. PMID:20598340

  17. Environmental implications of herbicide resistance: soil biology and ecology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil microbial community structure and activity are clearly linked to plant communities established in natural and agricultural ecosystems. A limited number of studies confirm that weeds alter their soil environment and select for specific microbial communities in the rhizosphere. Such rhizosphere m...

  18. Heavy metal pollution and soil enzymatic activity

    Microsoft Academic Search

    Germund Tyler

    1974-01-01

    The activity of hydrolytic soil enzymes was studied on spruce mor, polluted with Cu and Zn from a brass foundry in Sweden. Approximately straight regression lines were obtained between enzymatic activity or respiration rate and log Cu+Zn concentration, with highly significant negative regression coefficients for urease and acid phosphatase activity as well as respiration rate, whereas ß-glucosidase activity was not

  19. Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil is a diverse natural material characterized by solid, liquid, and gas phases that impart unique chemical, physical, and biological properties. Soil provides many key functions, including supporting plant growth and providing environmental remediation. Monitoring key soil properties and processe...

  20. Microbiological activity of soils populated by Lasius niger ants

    NASA Astrophysics Data System (ADS)

    Golichenkov, M. V.; Neimatov, A. L.; Kiryushin, A. V.

    2009-07-01

    Ants are the most widespread colonial insects assigned to the Hymenoptera order. They actively use soil as a habitat; being numerous, they create a specific microrelief. It is shown that ants affect microbiological processes of the carbon and nitrogen cycles. The carbon content in anthills remains stable throughout the growing season, and the respiration intensity is about three times higher as compared with that in the control soil. The highest methane production (0.08 nmol of CH4/g per day) in the anthill is observed at the beginning of the growing season and exceeds that in the control soil by four times. The most active nitrogen fixation (about 4 nmol of C2H4/g per h) in the anthill takes place in the early growing season, whereas, in the control soil, it is observed in the middle of the growing season. At the same time, the diazotrophic activity is higher in the control soil. The lowest denitrification in the anthill is observed at the beginning and end of the growing season. The dynamics of the denitrification in the anthill are opposite to the dynamics of the diazotrophic activity. We suppose that these regularities of the biological activity in the anthill are related to the ecology of the ants and the changes in their food preferences during the growing season.

  1. A review exploring biological activities of hydrazones

    PubMed Central

    Verma, Garima; Marella, Akranth; Shaquiquzzaman, Mohammad; Akhtar, Mymoona; Ali, Mohammad Rahmat; Alam, Mohammad Mumtaz

    2014-01-01

    The development of novel compounds, hydrazones has shown that they possess a wide variety of biological activities viz. antimicrobial, anticonvulsant, antidepressant, anti-inflammatory, analgesic, antiplatelet, antimalarial, anticancer, antifungal, antitubercular, antiviral, cardio protective etc., Hydrazones/azomethines/imines possess-NHN = CH- and constitute an important class of compounds for new drug development. A number of researchers have synthesized and evaluated the biological activities of hydrazones. This review aims at highlighting the diverse biological activities of hydrazones. PMID:24741273

  2. Restoring the biological crust cover of soils across biomes in arid North America

    NASA Astrophysics Data System (ADS)

    Garcia-Pichel, Ferran; Antoninka, Anita; Bowker, Matthew; Giraldo Silva, Ana; Nelson, Corey; Velasco Ayuso, Sergio; Barger, Nichole; Belnap, Jayne; Reed, Sasha; Duniway, Michael

    2015-04-01

    Biological soil crust communities provide important ecosystem services to arid lands, particularly regarding soil fertility and stability against erosion. In North America, and in many other areas of the globe, increasingly intense human activities, ranging from cattle grazing to military training, have resulted in the significant deterioration of biological soil surface cover of soils. With the intent of attaining sustainable land use practices, we are conducting a 5-year, multi-institutional research effort to develop feasible soil crusts restoration strategies for US military lands. We are including field sites of varying climatic regions (warm and cold deserts, in the Chihuahuan Desert and in the Great Basin, respectively) and varying edaphic characteristics (sandy and silty soils in each). We have multiple aims. First, we aim to establishing effective "biocrust nurseries" that produce viable and pedigreed inoculum, as a supply center for biocrust restoration and for research and development. Second, we aim to develop optimal field application methods of biocrust inoculum in a series of field trials. Currently in our second year of research, we will be reporting on significant advances made on optimizing methodologies for the large-scale supply of inoculum based on a) pedigreed laboratory cultures that match the microbial community structure of the original sites, and b) "in soil" biomass enhancement, whereby small amounts of local crusts are nursed under greenhouse conditions to yield hundred-fold increases in biomass without altering significantly community structure. We will also report on field trials for methodologies in field application, which included shading, watering, application of chemical polymers, and soil surface roughening. In a soon-to-be-initiated effort we also aim to evaluate soil and plant responses to biocrust restoration with respect to plant community structure, soil fertility, and soil stability, in multi-factorial field experiments. An important part of the plan will be to construct effective channels for sharing challenges and solutions in biocrust restoration with military and federal land managers.

  3. Spatial Pattern of Biological Soil Crust with Fractal Geometry

    NASA Astrophysics Data System (ADS)

    Ospina, Abelardo; Florentino, Adriana; Tarquis, Ana M.

    2015-04-01

    Soil surface characteristics are subjected to changes driven by several interactions between water, air, biotic and abiotic components. One of the examples of such interactions is provided through biological soil crusts (BSC) in arid and semi-arid environments. BSC are communities composed of cyanobacteria, fungi, mosses, lichens, algae and liverworts covering the soil surface and play an important role in ecosystem functioning. The characteristics and formation of these BSC influence the soil hydrological balance, control the mass of eroded sediment, increase stability of soil surface, and influence plant productivity through the modification of nitrogen and carbon cycle. This study focus on characterize the spatial arrangements of the BSC based on image analysis and fractal concepts. To this end, RGB images of different types of biological soil crust where taken, each image corresponding to an area of 3.6 cm2 with a resolution of 1024x1024 pixels. For each image and channel, mass dimension and entropy were calculated. Preliminary results indicate that fractal methods are useful to describe changes associated to different types of BSC. Further research is necessary to apply these methodologies to several situations.

  4. Assessing soil biological characteristics: a comparison of bulk soil community DNA, PLFA-, and Biolog™analyses

    Microsoft Academic Search

    F. Widmer; A. Fließbach; E. Laczkó; J. Schulze-Aurich; J. Zeyer

    2001-01-01

    Soil microbiological analyses may serve as a means for assessing soil characteristics. Standard microbiological culture-techniques, however, leave over 90% of the microorganisms in the environment unaccounted for. Several more recently developed analytical techniques such as DNA, phospholipid fatty acid (PLFA), and community level substrate utilization (CLSU) fingerprints allow for more detailed analyses of soil microbial communities. We applied analyses of

  5. Microbial activity in soils following steam treatment.

    PubMed

    Richardson, Ruth E; James, C Andrew; Bhupathiraju, Vishvesh K; Alvarez-Cohen, Lisa

    2002-01-01

    Steam enhanced extraction (SEE) is an aquifer remediation technique that can be effective at removing the bulk of non-aqueous phase liquid (NAPL) contamination from the subsurface, particularly highly volatile contaminants. However, low volatility compounds such as polynuclear aromatic hydrocarbons (PAHs) are less efficiently removed by this process. This research evaluated the effects of steam injection on soil microbial activity, community structure, and the potential for biodegradation of contaminants following steam treatment. Three different soils were evaluated: a laboratory-prepared microbially-enriched soil, soil from a creosote contaminated field site, and soil from a chlorinated solvent and waste oil contaminated field site. Results from field-scale steaming are also presented. Microbial activity before and after steam treatment was evaluated using direct epifluorescent microscopy (DEM) using the respiratory activity dye 5-cyano-2,3, ditolyl tetrazolium chloride (CTC) in conjunction with the fluorochrome 5-(4,6-dichlorotriazinyl) aminofluorescein (DTAF) to yield a quantitative assessment of active and total microbial numbers. DEM results indicate that steamed soils that were analyzed while still hot exhibited microbial activity levels that were below detection. However, soil samples that were slowly cooled, more closely reflecting the conditions of applied SEE, exhibited microbial activity levels that were comparable to presteamed soils. Samples from a field-site where steam was applied continuously for 6 weeks also showed high levels of microbial activity following cooling. The metabolic capabilities of the steamed communities were investigated by measuring cell growth in enrichment cultures on various substrates. These studies provided evidence that organisms capable of biodegradation were among the mesophilic populations that survived steam treatment. Fluorescent in situ hybridization (FISH) analysis of the soils with domain-level rRNA probes suggest that both Archaea and Bacteria survived steam exposure. PMID:12521292

  6. The Soil Moisture Active Passive (SMAP) Mission

    E-print Network

    Entekhabi, Dara

    The Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey. SMAP will make global measurements of ...

  7. Biological Soil Crusts: Webs of Life in the Desert

    USGS Publications Warehouse

    Belnap, Jayne

    2001-01-01

    Although the soil surface may look like dirt to you, it is full of living organisms that are a vital part of desert ecosystems. This veneer of life is called a biological soil crust. These crusts are found throughout the world, from hot deserts to polar regions. Crusts generally cover all soil spaces not occupied by green plants. In many areas, they comprise over 70% of the living ground cover and are key in reducing erosion, increasing water retention, and increasing soil fertility. In most dry regions, these crusts are dominated by cyanobacteria (previously called blue-green algae), which are one of the oldest known life forms. Communities of soil crusts also include lichens, mosses, microfungi, bacteria, and green algae. These living organisms and their by-products create a continuous crust on the soil surface. The general color, surface appearance, and amount of coverage of these crusts vary depending on climate and disturbance patterns. Immature crusts are generally flat and the color of the soil, which makes them difficult to distinguish from bare ground. Mature crusts, in contrast, are usually bumpy and dark-colored due to the presence of lichens, mosses, and high densities of cyanobacteria and other organisms.

  8. Biological spectra analysis: Linking biological activity profiles to molecular structure

    PubMed Central

    Fliri, Anton F.; Loging, William T.; Thadeio, Peter F.; Volkmann, Robert A.

    2005-01-01

    Establishing quantitative relationships between molecular structure and broad biological effects has been a longstanding challenge in science. Currently, no method exists for forecasting broad biological activity profiles of medicinal agents even within narrow boundaries of structurally similar molecules. Starting from the premise that biological activity results from the capacity of small organic molecules to modulate the activity of the proteome, we set out to investigate whether descriptor sets could be developed for measuring and quantifying this molecular property. Using a 1,567-compound database, we show that percent inhibition values, determined at single high drug concentration in a battery of in vitro assays representing a cross section of the proteome, provide precise molecular property descriptors that identify the structure of molecules. When broad biological activity of molecules is represented in spectra form, organic molecules can be sorted by quantifying differences between biological spectra. Unlike traditional structure–activity relationship methods, sorting of molecules by using biospectra comparisons does not require knowledge of a molecule's putative drug targets. To illustrate this finding, we selected as starting point the biological activity spectra of clotrimazole and tioconazole because their putative target, lanosterol demethylase (CYP51), was not included in the bioassay array. Spectra similarity obtained through profile similarity measurements and hierarchical clustering provided an unbiased means for establishing quantitative relationships between chemical structures and biological activity spectra. This methodology, which we have termed biological spectra analysis, provides the capability not only of sorting molecules on the basis of biospectra similarity but also of predicting simultaneous interactions of new molecules with multiple proteins. PMID:15625110

  9. Hands-on Activities for Teaching Biology

    NSDL National Science Digital Library

    Ingrid Waldron

    These hands-on, minds-on activities engage students in experiments or simulation activities and incorporate multiple questions designed to foster student understanding of important concepts in the life sciences. Topics covered include biological molecules, diffusion, metabolism, cell division, genetics, molecular biology, evolution, diversity, human physiology and design and interpretation of experiments. These activities were designed for teaching high school or middle school students, but many of these activities can also be used in non-major introductory college biology classes. To accommodate limited budgets, most of these activities can be carried out with minimum equipment and expense for supplies. Additional minds-on activities for teaching biology, including discussion activities, are available at http://serendip.brynmawr.edu/exchange/bioactivities. Most of the activities are described in student handouts and teacher notes; the student handouts are available as Word files for teachers to customize for their students.

  10. Concepts for Biologically Active Peptides

    PubMed Central

    Kastin, Abba J.; Pan, Weihong

    2012-01-01

    Here we review a unique aspect of CNS research on biologically active peptides that started against a background of prevalent dogmas but ended by exerting considerable influence on the field. During the course of refuting some doctrines, we introduced several concepts that were unconventional and paradigm-shifting at the time. We showed that (1) hypothalamic peptides can act ‘up’ on the brain as well as ‘down’ on the pituitary, (2) peripheral peptides can affect the brain, (3) peptides can cross the blood-brain barrier, (4) the actions of peptides can persist longer than their half-lives in blood, (5) perinatal administration of peptides can exert actions persisting into adulthood, (6) a single peptide can have more than one action, (7) dose-response relationships of peptides need not be linear, (8) the brain produces antiopiate as well as opiate peptides, (9) there is a selective high affinity endogenous peptide ligand for the mu-opiate receptor, (10) a peptide’s name does not restrict its effects, and (11) astrocytes assume an active role in response to metabolic disturbance and hyperleptinemia. The evolving questions in our laboratories reflect the diligent effort of the neuropeptide community to identify the roles of peptides in the CNS. The next decade is expected to see greater progress in the following areas: (a) interactions of peptides with other molecules in the CNS; (b) peptide involvement in cell-cell interactions; and (c) peptides in neuropsychiatric, autoimmune, and neurodegenerative diseases. The development of peptidomics and gene silencing approaches will expedite the formation of many new concepts in a new era. PMID:20726835

  11. Spatial variation of soil enzyme activities and microbial functional diversity in temperate alley cropping systems

    Microsoft Academic Search

    Nancy W. Mungai; Peter P. Motavalli; Robert J. Kremer; Kelly A. Nelson

    2005-01-01

    Spatially dependent patterns in microbial properties may exist in temperate alley cropping systems due to differences in litter quality and microclimate in areas under trees compared to those in the alleys. The effect of tree row location was evaluated for its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at

  12. ORIGINAL PAPER Soil enzyme activities as potential indicators

    E-print Network

    Paris-Sud XI, Université de

    with the activities of soil enzymes in natural secondary forest stands and adjacent larch plantation stands. & Methods a mountainous area, and the top 15 cm of the mineral soils were sampled from each field. & Results The soil on sampling time, and that the soil enzyme activities can be used as potential indicators of soil soluble

  13. Lichen-moss interactions within biological soil crusts

    NASA Astrophysics Data System (ADS)

    Ruckteschler, Nina; Williams, Laura; Büdel, Burkhard; Weber, Bettina

    2015-04-01

    Biological soil crusts (biocrusts) create well-known hotspots of microbial activity, being important components of hot and cold arid terrestrial regions. They colonize the uppermost millimeters of the soil, being composed of fungi, (cyano-) bacteria, algae, lichens, bryophytes and archaea in varying proportions. Biocrusts protect the (semi-) arid landscape from wind and water erosion, and also increase water holding capacity and nutrient content. Depending on location and developmental stage, composition and species abundance vary within biocrusts. As species live in close contact, they are expected to influence each other, but only a few interactions between different organisms have so far been explored. In the present study, we investigated the effects of the lichen Fulgensia fulgens whilst growing on the moss Trichostomum crispulum. While 77% of Fulgensia fulgens thalli were found growing associated with mosses in a German biocrust, up to 95% of Fulgensia bracteata thalli were moss-associated in a Swedish biocrust. In 49% (Germany) and in 78% (Sweden) of cases, thalli were observed on the moss T. crispulum and less frequently on four and three different moss species. Beneath F. fulgens and F. bracteata thalli, the mosses were dead and in close vicinity to the lichens the mosses appeared frail, bringing us to the assumption that the lichens may release substances harming the moss. We prepared a water extract from the lichen F. fulgens and used this to water the moss thalli (n = 6) on a daily basis over a time-span of three weeks. In a control setup, artificial rainwater was applied to the moss thalli (n = 6). Once a week, maximum CO2 gas exchange rates of the thalli were measured under constant conditions and at the end of the experiment the chlorophyll content of the moss samples was determined. In the course of the experiment net photosynthesis (NP) of the treatment samples decreased concurrently with an increase in dark respiration (DR). The control samples remained at the same stable level for both NP and DR over time. The chlorophyll content of the treatment samples was significantly lower than that of the controls. This supports our assumption that water extracts of F. fulgens may indeed cause a dieback of the host moss. In a next step of the project, the substances responsible for this detrimental effect on the moss will be identified. The accelerated dieback of the moss probably causes increased CO2 concentrations below the lichen thalli, improving their overall photosynthetic performance. Thus, both dead and living biomass in biocrusts increase upon this association, promoting microbial activity and the growth of vascular plant vegetation.

  14. Ice nucleation activity in the widespread soil fungus Mortierella alpina

    NASA Astrophysics Data System (ADS)

    Fröhlich-Nowoisky, Janine; Hill, Thomas C. J.; Pummer, Bernhard G.; Yordanova, Petya; Franc, Gary D.; Pöschl, Ulrich

    2015-04-01

    Biological residues in soil dust are a potentially strong source of atmospheric ice nucleators (IN). However, the sources and characteristics of biological - in particular, fungal - IN in soil dust have not been characterized. By analysis of the culturable fungi in topsoils, from a range of different land use and ecosystem types in south-east Wyoming, we found ice nucleation active (INA, i.e., inducing ice formation in the probed range of temperature and concentration) fungi to be both widespread and abundant, particularly in soils with recent inputs of decomposable organic matter. For example, in harvested and ploughed sugar beet and potato fields, and in the organic horizon beneath Lodgepole pine forest, their relative abundances and concentrations among the cultivable fungi were 25% (8 x 103 CFU g-1), 17% (4.8 x 103 CFU g-1) and 17% (4 x 103 CFU g-1), respectively. Across all investigated soils, 8% (2.9 x 103 CFU g-1) of fungal isolates were INA. All INA isolates initiated freezing at -5° C to -6° C and all belonged to a single zygomycotic species, Mortierella alpina (Mortierellales, Mortierellomycotina). By contrast, the handful of fungal species so far reported as INA all belong within the Ascomycota or Basidiomycota phyla. Mortierella alpina is known to be saprobic (utilizing non-living organic matter), widespread in soil and present in air and rain. Sequencing of the ITS region and the gene for ?-linolenic elongase revealed four distinct clades, affiliated to different soil types. The IN produced by M. alpina seem to be extracellular proteins of 100-300 kDa in size which are not anchored in the fungal cell wall. Ice nucleating fungal mycelium will ramify topsoils and probably also release cell-free IN into it. If these IN survive decomposition or are adsorbed onto mineral surfaces, these small cell-free IN might contribute to the as yet uncharacterized pool of atmospheric IN released by soils as dusts.

  15. Phenol oxidase activity in secondary transformed peat-moorsh soils

    NASA Astrophysics Data System (ADS)

    Sty?a, K.; Szajdak, L.

    2009-04-01

    The chemical composition of peat depends on the geobotanical conditions of its formation and on the depth of sampling. The evolution of hydrogenic peat soils is closely related to the genesis of peat and to the changes in water conditions. Due to a number of factors including oscillation of ground water level, different redox potential, changes of aerobic conditions, different plant communities, and root exudes, and products of the degradation of plant remains, peat-moorsh soils may undergo a process of secondary transformation conditions (Sokolowska et al. 2005; Szajdak et al. 2007). Phenol oxidase is one of the few enzymes able to degrade recalcitrant phenolic materials as lignin (Freeman et al. 2004). Phenol oxidase enzymes catalyze polyphenol oxidation in the presence of oxygen (O2) by removing phenolic hydrogen or hydrogenes to from radicals or quinines. These products undergo nucleophilic addition reactions in the presence or absence of free - NH2 group with the eventual production of humic acid-like polymers. The presence of phenol oxidase in soil environments is important in the formation of humic substances a desirable process because the carbon is stored in a stable form (Matocha et al. 2004). The investigations were carried out on the transect of peatland 4.5 km long, located in the Agroecological Landscape Park host D. Chlapowski in Turew (40 km South-West of Pozna?, West Polish Lowland). The sites of investigation were located along Wysko? ditch. The following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo in two layers: cartel (0-50cm) and cattle (50-100cm). The object of this study was to characterize the biochemical properties by the determination of the phenol oxidize activity in two layers of the four different peat-moors soils used as meadow. The phenol oxidase activity was determined spectrophotometrically by measuring quinone formation at ?max=525 nm with catechol as substrate by method of Perucci et al. (2000). In peat the highest activities of phenol oxidase was observed in the combinations marked as Shelterbelt and whereas the lowest - in Zbechy, Bridge and Hirudo. Activities of this enzyme in peat ranged from 15.35 to 38.33 ?mol h-1g d.m soil. Increased activities of phenol oxidase have been recorded on the depth 50-100cm - catotelm (21.74-38.33 ?mol h-1g d.m soil) in comparison with the depth 0-50cm - acrotelm (15.35-28.32 ?mol h-1g d.m soil). References Freeman, C., Ostle N.J., Fener, N., Kang H. 2004. A regulatory role for phenol oxidase during decomposition in peatlands. Soil Biology and Biochemistry, 36, 1663-1667. Matocha Ch.J., Haszler G.R., Grove J.H. 2004. Nitrogen fertilization suppresses soil phenol oxidase enzyme activity in no-tillage systems. Soil Science, 169/10, 708-714. Perucci P., Casucci C., Dumontet S. 2000. An improved method to evaluate the o-diphenol oxidase activity of soil. Soil Biology and Biochemistry, 32, 1927-1933. Sokolowska Z., Szajdak L., Matyka-Sarzy?ska D. 2005. Impact of the degree of secondary transformation on amid-base properties of organic compounds in mucks. Geoderma, 127, 80-90. Szajdak L., Szczepa?ski M., Bogacz A. 2007. Impact of secondary transformation of peat-moorsh soils on the decrease of nitrogen and carbon compounds in ground water. Agronomy Research, 5/2, 189-200.

  16. Organic matter components, aggregate stability and biological activity in a horticultural soil fertilized with different rates of two sewage sludges during ten years

    Microsoft Academic Search

    R Albiach; R Canet; F Pomares; F Ingelmo

    2001-01-01

    The effects of the application as fertilizer during ten years of two sewage sludges (aerobically and anaerobically digested, at rates of 400, 800, and 1200 kg of N\\/ha yr), on the aggregate stability and contents of related organic matter components, microbial biomass and levels of five enzymatic activities (alkaline phosphomonoesterase, phosphodiesterase, urease, arylsulphatase and dehydrogenase) were investigated. The application of

  17. The biological factors influence on the conversion of mineral components of Extremely Arid Desert Soils (Kazakhstan)

    NASA Astrophysics Data System (ADS)

    Kutovaya, Olga; Vasilenko, Elena; Lebedeva, Marina; Tkhakakhova, Azida

    2013-04-01

    Extremely arid soils of stony deserts (hamadas) along the southern periphery of the Ili Depression are considered to be analogous to extremely arid soils of Mongolia, also named as "ultra-arid primitive gray-brown soils." In general, the morphology of extremely arid soils of hamadas in the Ili Depression is similar to that of the soils of stony deserts in other parts of the world, including the Gobi, Atacama, and Tarim deserts. The diagnostics of the active communities of microorganisms were performed according to the method of Rybalkina-Kononenko. The exact identification of the living forms of microorganisms to the species level is not always possible with the use of this method. However, it allows us to study the physiological role of the microorganisms and their ecological functions, including the relationships with the soil matrix and other organisms. In particular, it is possible to estimate the contribution of the microorganisms to the transformation of mineral soil components. The obtained materials allow us to conclude that the extremely arid desert soils are characterized by the very high biological activity during short periods of the increased soil moistening after rare and strong rains. The diversity of living forms is very considerable; both prokaryotes (cyanobacteria, actinomycetes, and iron bacteria) and protists (green algae, diatoms, and dinoflagellates) are developed in the soil. Thus, during a short period after the rains, these microorganisms pass from the stage of anabiosis to the stage of active growth and reproduction. Then, upon drying of the soil, the biotic activity of the soil slows down and, finally, terminates. The organisms remain in the state of anabiosis until the next rain. During the period of active growth, the microorganisms compose a specific consortium of different species and exert a profound impact on the soil properties. They participate in the transformation of the soil minerals with the formation of amorphous substances that are clearly seen in biofilms on the surface of gravels of the desert pavement and on the walls of vesicular pores in the crust and subcrust (AKL) horizons of the soil. The organomineral compounds are accumulated in the vesicular pores due to the synthesis and mineralization of the microbial biomass. This is a specific feature of the humus-accumulative process in the extremely arid desert soils. The biogenic transformation of iron-containing minerals, the mobility of iron, and its accumulation in films and coagulated microforms is largely due to the living activity of iron bacteria. These iron pedofeatures are specific of the extremely arid desert soils. We suppose that some part of vesicular pores in the AKL horizon has a microbiological origin, because separate bacterial cells may form intracellular gas vacuoles and extracellular gas bulbs, as well as membrane sacs and cell dilatations that can shape the vesicular pores. In general, our data indicate that soils, including extremely arid desert soils, serve as reservoirs of the microbial diversity and ensure the development and preservation of diverse microorganisms with specific mechanisms of adaptation to the sharp changes in the environmental conditions. This biota-protecting role of soils is particularly well pronounced during the climatic pessimum. This study was supported by the Russian Foundation for Basic Research, project no. 12-04-00990a.

  18. Long-term effects of fertilizer on soil enzymatic activity of wheat field soil in Loess Plateau, China.

    PubMed

    Hu, Weigang; Jiao, Zhifang; Wu, Fasi; Liu, Yongjun; Dong, Maoxing; Ma, Xiaojun; Fan, Tinglu; An, Lizhe; Feng, Huyuan

    2014-12-01

    The effects of long-term (29 years) fertilization on local agro-ecosystems in the Loess Plateau of northwest China, containing a single or combinations of inorganic (Nitrogen, N; Phosphate, P) and organic (Mature, M Straw, S) fertilizer, including N, NP, SNP, M, MNP, and a control. The soil enzymes, including dehydrogenase, urease, alkaline phosphatase, invertase and glomalin, were investigated in three physiological stages (Jointing, Dough, and Maturity) of wheat growth at three depths of the soil profile (0-15, 16-30, 31-45 cm). We found that the application of farmyard manure and straw produced the highest values of soil enzymatic activity, especially a balanced applied treatment of MNP. Enzymatic activity was lowest in the control. Values were generally highest at dough, followed by the jointing and maturity stages, and declined with soil profile depth. The activities of the enzymes investigated here are significantly correlated with each other and are correlated with soil nutrients, in particular with soil organic carbon. Our results suggest that a balanced application of fertilizer nutrients and organic manure (especially those containing P) has positive effects on multiple soil chemical parameters, which in turn enhances enzyme activity. We emphasize the role of organic manure in maintaining soil organic matter and promoting biological activity, as its application can result in a substantial increase in agricultural production and can be sustainable for many years. PMID:25134679

  19. Minds-On Activities for Teaching Biology

    NSDL National Science Digital Library

    Ingrid Waldron

    These minds-on activities include analysis and discussion activities, experiments, and simulation activities to foster student understanding of important concepts in the life sciences. Topics covered include biological molecules, membranes and osmosis, cellular respiration and photosynthesis, cell structure and function, cell division, genetics, molecular biology, evolution, diversity, human physiology and health, and design and interpretation of experiments. These activities were designed for teaching high school and middle school students, but many of them can also be used in non-major introductory college biology classes. Most of the activities are described in student handouts and teacher notes; the student handouts are available as Word files for teachers to customize for their students. The hands-on experiments and simulation activities are available at http://serendip.brynmawr.edu/sci_edu/waldron/. To accommodate limited budgets, most of the hands-on activities can be carried out with minimum equipment and expense for supplies.

  20. Biological activities and distribution of plant saponins

    Microsoft Academic Search

    S. G. Sparg; M. E. Light; J. van Staden

    2004-01-01

    Plant saponins are widely distributed amongst plants and have a wide range of biological properties. The more recent investigations and findings into their biological activities were summarized. Isolation studies of saponins were examined to determine which are the more commonly studied plant families and in which families saponins have been identified.

  1. Changes in the biological diversity and concentration of total DNA under the influence of mineral fertilizers in agrochernozemic soils

    NASA Astrophysics Data System (ADS)

    Tkhakakhova, Azida; Kutovaya, Olga; Ivanova, Ekaterina; Pavlyuchenko, Anatoly

    2014-05-01

    Chernozems represent the most valuable soil resource for Russian agriculture. Their sustainable use in intensive farming systems with preservation of the biological diversity and biological activity of these soils is of crucial importance for the agri-environmental security of Russia. We studied the influence of different rates of mineral fertilizers on the biological activity of chernozems on experimental fields of the Dokuchaev Research Institute of Agriculture in Kamennaya Steppe (Voronezh oblast). Soil samples were taken at the end of April 2013 from the plow horizon on trials with different rates of fertilization: NPK-0, NPK-60, and NPK-120 (kg/ha); a long-term fallow plot was used as an absolute control. The biological activity was analyzed by routine inoculation methods and by the molecular biology techniques based on DNA isolation from the soil samples. Quantitative parameters of the isolated and purified DNA were determined by measuring the fluorescence of the DNA preparations with added intercalating dyes; GelDoc XR system and Image Lab and TotalLab Quant. software were used. Microbiological studies showed the high biological activity of the chernozems soil in all the trials. No significant differences were found between the trials for the microbiological processes of the carbon cycle. There was a weakly expressed tendency for an increase in the activity of actinomycetes from the soil with zero fertilization (5.11 log10CFU/g) to the soil with maximum (NPK-120) fertilization (5.69 log10CFU/g) and the fallow soil (5.73 log10CFU/g); the number of cultivated micromycetes decreased from the soil with zero fertilization (4.76 log10CFU/g) to the soil with maximum fertilization (4.14 log10CFU/g) and to the fallow soil (4.1 log10CFU/g). A less equilibrium state is typical of the microorganisms participating in the nitrogen cycle. The number of cultivated aerobic and anaerobic nitrogen-fixing bacteria somewhat increased in the fertilized trials (NPK-60, NPK-120). The most active development of denitrifiers was in the fallow soil. It is known that cultivated forms comprise only about 1 to 10% of the total number of soil microorganisms. Quantitative analysis by the methods of molecular biology makes it possible to consider the full range of microorganisms. The concentration of extracted DNA can serve as an indicator of the total "biogenity" of the soil, as we isolated the genetic material of all organisms living in the soil. The highest concentration of DNA found in the samples from the fallow soil. Much lower values were found in the soils treated with mineral fertilizers: 38.9% in trial NPK-60 and 53.3% in trials NPK-120 and NPK-0. Thus, to sustain biota in cultivated chernozems and to improve the ecological state of the fields, the rates of mineral fertilizers have to be properly controlled. Moderate rates can be recommended. Features of the soil microbiome can serve as universal and sensitive indicators of the state of the soils under different farming systems. The quantitative analysis of isolated total DNA is an efficient tool to control the ecological state of the soils, especially those involved in agriculture.

  2. Assessment of soil biological quality index (QBS-ar) in different crop rotation systems in paddy soils

    NASA Astrophysics Data System (ADS)

    Nadimi-Goki, Mandana; Bini, Claudio; haefele, Stephan

    2013-04-01

    New methods, based on soil microarthropods for soil quality evaluation have been proposed by some Authors. Soil microarthropods demonstrated to respond sensitively to land management practices and to be correlated with beneficial soil functions. QBS Index (QBS-ar) is calculated on the basis of microarthropod groups present in a soil sample. Each biological form found in the sample receives a score from 1 to 20 (eco-morphological index, EMI), according to its adaptation to soil environment. The objective of this study was to evaluate the effect of various rotation systems and sampling periods on soil biological quality index, in paddy soils. For the purpose of this study surface soil samples (0-15 cm depth) were collected from different rotation systems (rice-rice-rice, soya-rice-rice, fallow-rice and pea-soya-rice) with three replications, and four sampling times in April (after field preparation), June (after seedling), August (after tillering stage) and October (after rice harvesting). The study area is located in paddy soils of Verona area, Northern Italy. Soil microarthropods from a total of 48 samples were extracted and classified according to the Biological Quality of Soil Index (QBS-ar) method. In addition soil moisture, Cumulative Soil Respiration and pH were measured in each site. More diversity of microarthropod groups was found in June and August sampling times. T-test results between different rotations did not show significant differences while the mean difference between rotation and different sampling times is statistically different. The highest QBS-ar value was found in the fallow-rice rotation in the forth soil sampling time. Similar value was found in soya-rice-rice rotation. Result of linear regression analysis indicated that there is significant correlation between QBS-ar values and Cumulative Soil Respiration. Keywords: soil biological quality index (QBS-ar), Crop Rotation System, paddy soils, Italy

  3. ORIGINAL PAPER Physicochemical properties and biological activities

    E-print Network

    Boyer, Edmond

    and antimicrobial activities, as well as the physicochemical features, of ovine sodium caseinate (NaCAS) subjectedORIGINAL PAPER Physicochemical properties and biological activities of ovine caseinate hydrolysates, Cory- nebacterium fimi, and Listeria monocytogenes, showing antifungal activity of the hydrolysates

  4. Soil Biology & Biochemistry 39 (2007) 232238 Identification of in situ 2,4-dichlorophenoxyacetic acid-degrading soil

    E-print Network

    Sims, Gerald K.

    2007-01-01

    of the herbicide, 2,4- dichlorophenoxyacetic acid (2,4-D) in soil samples. Soils were unamended or amendedSoil Biology & Biochemistry 39 (2007) 232­238 Identification of in situ 2,4-dichlorophenoxyacetic possible with the molecular-based methods alone. Published by Elsevier Ltd. Keywords: 2,4

  5. Emerging Patterns In The Isotopic Composition Of Soil CO2 Concentrations, Soil CO2 Production, And Soil-Atmosphere CO2 Exchange At The Watershed Scale: On The Intersection Between Hydrology And Biology In The Critical Zone

    NASA Astrophysics Data System (ADS)

    Riveros-Iregui, D. A.; Liang, L.; Lorenzo, T. M.

    2014-12-01

    Stable isotopes are commonly used to understand how physical and biological processes mediate the exchange of carbon between terrestrial ecosystems and the atmosphere. Numerous studies have described fundamental relationships between environmental variables, the carbon isotopic composition (?13C) of recently assimilated sugars in plants, litter, soil carbon, or recently respired CO2. However, studies that examine the spatial variability of the 13C content of forest soils at the landscape scale are lacking. We report on measurements of the carbon isotopic composition of soil CO2 concentrations (?13CC), soil CO2 production (?13CP), and soil-atmosphere CO2 exchange (?13CD) across a subalpine forest of the northern Rocky Mountains of Montana over two growing seasons. We evaluate the variability of these measurements across different landscape positions. Our analysis demonstrates that soil moisture and the lateral redistribution of soil water are strong predictors of the spatial variability of ?13CC, ?13CP, and ?13CD at the watershed scale. We suggest that there are concomitant yet independent effects of soil water on physical (i.e., soil gas diffusivity) and biological (i.e., photosynthetic activity) processes that mediate the 13C composition of forest soils. We show systematic spatial variability in the ?13C of forest soils at the landscape scale that can be useful to accurately predict and model land-atmosphere CO2 exchange over complex terrain.

  6. Physical and biological soil attributes due to soil management on sugarcane

    NASA Astrophysics Data System (ADS)

    Fernandes, Carolina; Viviane Truber, Priscila; Corá, José Eduardo

    2013-04-01

    The use of different crops can improve the physical and biological soil attributes, reducing soil and environmental degradation. The objective of this study was to evaluate the effect of different land uses on the glomalin fractions, total external mycelium and soil aggregation. The experiment was carried out in Brazil (21°14'05'' S and 48°17'09'' W) in eutroferric Red Oxisol (clay content = 700 g kg-1) and acric Oxisol (clay content = 450 g kg-1). The soil was submitted to two soybean growing seasons, with different crops (millet and sunnhemp) between them, during two sugarcane growth interval periods. The experimental design was a randomized block with five replications and four treatments, characterized by different land uses during the interval between two sugarcane growth periods. The land uses were the crops of: soybean, soybean/millet/soybean, soybean/sunnhemp/soybean and soybean/fallow/soybean. Soil samples were taken at the 0 - 0.10 m depth after the first sugarcane harvest. On both soils the glomalin fractions were not influenced by the different land uses. On the eutroferric Red Oxisol, the use soybean/millet/soybean promoted the higher amount of total external mycelium and on the acric Oxisol soybean/fallow/soybean promoted the lower amount. The aggregate stability indexes on both soils types were not affected by the land uses. On the eutroferric Red Oxisol, the aggregate mean weight diameter was not influenced by the different land uses, but on the acric Oxisol, the uses soybean and soybean/millet/soybean promoted the higher values. The results indicated that the effects of plants on amount of total external mycelium and aggregate mean weight diameter of Oxisol are different depend upon the soil texture and soil fertility.

  7. Effects of organic versus conventional management on chemical and biological parameters in agricultural soils

    Microsoft Academic Search

    Anne D. van Diepeningen; Oscar J. de Vos; Gerard W. Korthals; Ariena H. C. van Bruggen

    2006-01-01

    A comparative study of organic and conventional arable farming systems was conducted in The Netherlands to determine the effect of management practices on chemical and biological soil properties and soil health. Soils from thirteen accredited organic farms and conventionally managed neighboring farms were analyzed using a polyphasic approach combining traditional soil analysis, culture-dependent and independent microbiological analyses, a nematode community

  8. Soil Moisture Active Passive Validation Experiment 2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil Moisture Active Passive Validation Experiment 2008 (SMAPVEX08) was conducted to address specific issues identified by the SMAP satellite mission (launch 2013). SMAP is currently addressing issues related to the development and selection of retrieval algorithms as well as refining the mission de...

  9. The effect of model soil contamination with Cr, Cu, Ni, and Pb on the biological properties of soils in the dry steppe and semidesert regions of southern Russia

    NASA Astrophysics Data System (ADS)

    Kolesnikov, S. I.; Spivakova, N. A.; Kazeev, K. Sh.

    2011-09-01

    Model soil contamination with Cr, Cu, Ni, and Pb in the dry steppes and semideserts of southern Russia has worsened the biological soil properties. With respect to the degree of deterioration of the biological properties, the soils can be arranged in the following sequence: dark chestnut soils > chestnut soils > light chestnut soils > brown semidesert soils > sandy brown semidesert soils. The sequence of metal oxides according to the adverse effect on the biological soil properties is as follows: CrO3 > CuO ? PbO ? NiO.

  10. Soil organic carbon buffers heavy metal contamination on semiarid soils: Effects of different metal threshold levels on soil microbial activity

    Microsoft Academic Search

    J. L. Moreno; F. Bastida; M. Ros; T. Hernández; C. García

    2009-01-01

    Traditionally, three threshold levels have been accepted for heavy metal concentrations in agricultural soils, depending on soil pH. The aim of this work was to ascertain how the three threshold values proposed for Cd (3, 6.5, and 12.5 mg kg?1) and Zn (300, 650, and 1300 mg kg?1) really affect soil microbial activity. Two soils, a scrubland soil and a forest soil, differing widely

  11. Interactions Between Xenobiotics and Microbial and Enzymatic Soil Activity

    Microsoft Academic Search

    Liliana Gianfreda; Maria A. Rao

    2008-01-01

    In the second half of the twentieth century, the indiscriminate release of xenobiotic chemicals of different chemical and structural complexity into the environment provoked serious and most often irreversible alterations of the natural environmental balance. Indeed, soil contamination by highly toxic compounds has greatly increased, with negative, irreversible effects on soil quality and health. Several chemical, biological, and biochemical soil

  12. Nitrogen Fixation and Leaching of Biological Soil Crust Communities in Mesic Temperate Soils

    Microsoft Academic Search

    Roberta M. Veluci; Deborah A. Neher; Thomas R. Weicht

    2006-01-01

    Biological soil crust is composed of lichens, cyanobacteria, green algae, mosses, and fungi. Although crusts are a dominant\\u000a source of nitrogen (N) in arid ecosystems, this study is among the first to demonstrate their contribution to N availability\\u000a in xeric temperate habitats. The study site is located in Lucas County of Northwest Ohio. Using an acetylene reduction technique,\\u000a we demonstrated

  13. Biological activity of earthworm casts: An assessment of plant growth promotor levels in the casts

    Microsoft Academic Search

    R V Krishnamoorthy; S N Vajranabhaiah

    1986-01-01

    Biochemical analyses and auxin and cytokinin bioassays were performed to test the biological activity of wormcasts. Both cellulose\\u000a paper pulp and soil casts ofLampito mauritii were rich in ammonia, urea, organic carbon content, organic matter, soluble phosphorus and ionic potassium levels. The total\\u000a nitrogen content of the soil remained unaffected by worm activations. The casts ofLampito mauritii, Pheretima elongata, Pontoscolex

  14. Impacts of off-road vehicles on nitrogen cycles in biological soil crusts: Resistance in different U.S. deserts

    USGS Publications Warehouse

    Belnap, J.

    2002-01-01

    Biological soil crusts are an important component of desert ecosystems, as they influence soil stability and fertility. This study examined and compared the short-term vehicular impacts on lichen cover and nitrogenase activity (NA) of biological soil crusts. Experimental disturbance was applied to different types of soil in regions throughout the western U.S. (Great Basin, Colorado Plateau, Sonoran, Chihuahuan, and Mojave deserts). Results show that pre-disturbance cover of soil lichens is significantly correlated with the silt content of soils, and negatively correlated with sand and clay. While disturbance appeared to reduce NA at all sites, differences were statistically significant at only 12 of the 26 sites. Cool desert sites showed a greater decline than hot desert sites, which may indicate non-heterocystic cyanobacterial species are more susceptible to disturbance than non-heterocystic species. Sandy soils showed greater reduction of NA as sand content increased, while fine-textured soils showed a greater decline as sand content increased. At all sites, higher NA before the disturbance resulted in less impact to NA post-disturbance. These results may be useful in predicting the impacts of off-road vehicles in different regions and different soils. ?? 2002 Published by Elsevier Science Ltd.

  15. Effects of the halophytes Tecticornia indica and Suaeda fruticosa on soil enzyme activities in a Mediterranean sabkha

    Microsoft Academic Search

    Youssef Ouni; Abdelbasset Lakhdar; Mokded Rabhi; Abderrazak Smaoui; Maria A. Rao; Chedly Abdelly

    2012-01-01

    In the present work, we studied the effectiveness of the predominant halophytes of Soliman sabkha (Tecticornia indica and Suaeda fruticosa) to promote soil biological activities and ecosystem productivity. Soil Arylsulphatese ARY, ?-glucosidase ?-GLU, phosphatase PHO, invertase INV, urease URE and dehydogenase DES activities in Extra- and Intra-tuft halophytes and plant productivity were assessed. Results revealed a high increase of microbial

  16. Arylsulfatase activity in soil and soil extracts using natural and artificial substrates

    Microsoft Academic Search

    J. K. Whalen; P. R. Warman

    1996-01-01

    The arylsulfatase activity of soil and humic arylsulfatase complexes extracted from soil were measured using the substrates p-nitrophenyl sulfate and low molecular weight (500–10000) soil ester sulfate compounds. Soil samples from the Aphorizon of a Podzol from S-amended wheat plots and a Regosol from dykeland hayfield plots were investigated. Soil arylsulfatase activity (assayed with p-nitrophenyl sulfate) in the fall was

  17. The plasminogen activator system: biology and regulation

    Microsoft Academic Search

    J. P. Irigoyen; P. Muńoz-Cánoves; L. Montero; M. Koziczak; Y. Nagamine

    1999-01-01

    .   The regulation of plasminogen activation involves genes for two plasminogen activators (tissue type and urokinase type),\\u000a two specific inhibitors (type 1 and type 2), and a membrane-anchored urokinase-type plasminogen-activator-specific receptor.\\u000a This system plays an important role in various biological processes involving extracellular proteolysis. Recent studies have\\u000a revealed that the system, through interplay with integrins and the extracellular matrix protein

  18. Biological activity of liposomal vanillin.

    PubMed

    Castan, Leniher; Del Toro, Grisel; Fernández, Adolfo A; González, Manuel; Ortíz, Emilia; Lobo, Daliana

    2013-06-01

    This article presents a study of vanillin encapsulation inside multilamellar liposomes, with emphasis on the evaluation of antioxidant activity, the hemolytic effect, and the antisickling properties of these products. Egg phosphatidylcholine-cholesterol and egg phosphatidylcholine-cholesterol-1-O-decylglycerol liposomes were prepared by mechanical dispersion, all with vanillin included. Vesicles were characterized by determination of encapsulation efficiency and vanillin retention capacity. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. The hemolytic effect of liposomes was also evaluated by spectrophotometry, as well as the antisickling activity by the Huck test using optical microscopy. Results showed that the lipid composition of liposomes did not significantly affect the encapsulation efficiency. Stable vesicles were obtained with a high retention percentage of vanillin. Liposomes exhibited a high capture of the DPPH radical compared to free vanillin and 1-O-decylglycerol (C10) in solution. Vesicles caused no significant hemolisys in normal erythrocytes, nor in those coming from patients with sickle cell anemia. Vanillin encapsulated in liposomes retained its antisickling activity, with a greater effect for C10-containing vesicles. Our results show that vanillin encapsulation in liposomes is a way to enhance the pharmacologic properties of this molecule using a suitable vehicle. PMID:23767864

  19. Effect of activated carbon on microbial bioavailability of phenanthrene in soils

    SciTech Connect

    Yang, Y.; Hunter, W.; Tao, S.; Crowley, D.; Gan, J. [University of California Riverside, Riverside, CA (United States). Dept. of Environmental Science

    2009-11-15

    Bioavailability is a governing factor that controls the rate of biological degradation of hydrophobic organic contaminants in soil. Among the solid phases that can adsorb hydrophobic organic contaminants in soil, black carbon (BC) exerts a particularly significant effect on phase distribution. However, knowledge on the effect of BC on the microbial availability of polycyclic aromatic hydrocarbons in soil is still limited. In the present study, the effect of a coal-derived activated carbon on the bioavailability of phenanthrene (PHE) during its degradation by Mycobacterium vanbaalenii PYR-1 was measured in three soils. The freely dissolved concentration of PHE was concurrently determined in soil solutions using disposable polydimethylsiloxane fibers. The results showed that PHE mineralization was significantly inhibited after addition of activated carbon in all test soils. After 216 h, only 5.20, 5.83, and 6.85% of PHE was degraded in the 0.5% BC-amended soils initially containing organic carbon at 0.23, 2.1, and 7.1%, respectively. Significant correlation was found between PHE degradability and freely dissolved concentration, suggesting that BC affected PHE bioavailability by decreasing chemical activity. The effect of activated carbon in the amended soils was attributed to its enhancement of soil surface areas and pore volumes. Results from the present study clearly highlighted the importance of BC for influencing the microbial availability of polycyclic aromatic hydrocarbons in soils.

  20. Microbial activity and soil organic matter decay in roadside soils polluted with petroleum hydrocarbons

    NASA Astrophysics Data System (ADS)

    Mykhailova, Larysa; Fischer, Thomas; Iurchenko, Valentina

    2015-04-01

    It has been demonstrated previously that hydrocarbon addition to soil provokes soil organic matter priming (Zyakun et al., 2011). It has further been shown that petroleum hydrocarbons deposit to roadside soils bound to fine mineral particles and together with vehicle spray (Mykhailova et al., 2014), and that hydrocarbon concentrations decrease to safe levels within the first 15 m from the road, reaching background concentrations at 60-100 m distance (Mykhailova et al., 2013). It was the aim of this study to (I) identify the bioavailability of different petroleum hydrocarbon fractions to degradation and to (II) identify the native (i.e. pedogenic) C fraction affected by hydrocarbon-mediated soil organic matter priming during decay. To address this aim, we collected soil samples at distances from 1 to 100 m (sampling depth 15 cm) near the Traktorostroiteley avenue and the Pushkinskaya street in Kharkov, as well as near the country road M18 near Kharkov, Ukraine. The roads have been under exploitation for several decades, so microbial adaptation to enhanced hydrocarbon levels and full expression of effects could be assumed. The following C fractions were quantified using 13C-CP/MAS-NMR: Carbohydrates, Proteins, Lignin, Aliphates, Carbonyl/Carboxyl as well as black carbon according to Nelson and Baldock (2005). Petroleum hydrocarbons were determind after hexane extraction using GC-MS and divided into a light fraction (chain-length C27, Mykhailova et al., 2013). Potential soil respiration was determined every 48 h by trapping of CO2 evolving from 20 g soil in NaOH at 20 ° C and at 60% of the maximum water holding capacity and titration after a total incubation period of 4 weeks in the lab. It was found that soil respiration positively correlated with the ratio of the light fraction to the sum of medium and heavy fractions of petroleum hydrocarbons, which indicates higher biodegradation primarily of the light petroleum hydrocarbon fraction. Further, soil respiration was positively correlated with the carbohydrate fraction and negatively correlated with the aliphatic fraction of the soil C, while carbohydrate-C and alkyl-C increased and decreased with distance from the road, respectively. It is proposed that petroleum hydrocarbons supress soil biological activity at concentrations above 1500 mg kg-1, and that soil organic matter priming primarily affects the carbohydrate fraction of soil organic matter. It can be concluded that the abundance of solid carbohydrates (O-alkyl C) is of paramount importance for the hydrocarbon mineralization under natural conditions, compared to more recalcitrant SOM fractions (mainly aromatic and alkyl C). References Mykhailova, L., Fischer, T., Iurchenko, V. (2013) Distribution and fractional composition of petroleum hydrocarbons in roadside soils. Applied and Environmental Soil Science, vol. 2013, Article ID 938703, 6 pages, DOI 10.1155/2013/938703 Mykhailova, L., Fischer, T., Iurchenko, V. (2014) Deposition of petroleum hydrocarbons with sediment trapped in snow in roadside areas. Journal of Environmental Engineering and Landscape Management 22(3):237-244, DOI 10.3846/16486897.2014.889698 Nelson P.N. and Baldock J.A. (2005) Estimating the molecular composition of a diverse range of natural organic materials from solid-state 13C NMR and elemental analyses, 2005, Biogeochemistry (2005) 72: 1-34, DOI 10.1007/s10533-004-0076-3 Zyakun, A., Nii-Annang, S., Franke, G., Fischer, T., Buegger, F., Dilly, O. (2011) Microbial Actvity and 13C/12C Ratio as Evidence of N-Hexadecane and N-Hexadecanoic Acid Biodegradation in Agricultural and Forest Soils. Geomicrobiology Journal 28:632-647, DOI 10.1080/01490451.2010.489922

  1. Obtaining edaphic biostimulants/biofertilizers from different sewage sludges. Effects on soil biological properties.

    PubMed

    Rodríguez-Morgado, Bruno; Gómez, Isidoro; Parrado, Juan; García-Martínez, Ana M; Aragón, Carlos; Tejada, Manuel

    2015-09-01

    We studied the influence of six edaphic biostimulants/biofertilizers (BSs) manufactured by the pH-stat method from different sewage sludge (SS): SS1 (an anaerobic mature sludge, one year old), SS2 (an aerobic young sludge, without maturation) and SS3 (an aerobic mature sludge, four months old), not previously autoclaved (A) and autoclaved (B), by analysing their effects on soil biological properties. Soil enzymatic activities were measured at 1, 3, 5, 7, 15, 30 and 60 days of the incubation period, whereas the 16S rDNA-DGGE profiles were determined at 0, 5 and 60 days. The enzymatic activities were significantly stimulated. The highest stimulation was found in the B2 treatment followed by B3, A2, A3, B1 and A1 treatments. Increasing the number of lower molecular weight proteins in the BS enhances the stimulation of soil enzymatic activities. The application of BS caused at 5 days of the incubation period temporal variations in the soil bacterial community structure. PMID:25732482

  2. Marine Biology Activities. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  3. In Search of a Better Bean: A Simple Activity to Introduce Plant Biology

    ERIC Educational Resources Information Center

    Spaccarotella, Kim; James, Roxie

    2014-01-01

    Measuring plant stem growth over time is a simple activity commonly used to introduce concepts in growth and development in plant biology (Reid & Pu, 2007). This Quick Fix updates the activity and incorporates a real-world application: students consider possible effects of soil substrate and sunlight conditions on plant growth without needing…

  4. Biological activity of vanadium compounds

    Microsoft Academic Search

    Anna Goc

    2006-01-01

    Vanadium compounds are characterised by a broad spectrum of action in vivo and in vitro. Their insulin-mimetic activity is manifested in their ability to normalize changes observed in both clinical and experimental\\u000a diabetes (i.e. hyperglycaemia, hyperlipidaemia, lowered cell sensitivity to insulin) through the regulation of carbohydrate\\u000a and lipid metabolism and the removal of secondary symptoms of this disease (as e.g.

  5. Isoxanthohumol - Biologically active hop flavonoid.

    PubMed

    ?o?nierczyk, Anna Katarzyna; M?czka, Wanda Krystyna; Grabarczyk, Ma?gorzata; Wi?ska, Katarzyna; Wo?niak, Edyta; Anio?, Miros?aw

    2015-06-01

    Isoxanthohumol (IXN), apart from xanthohumol (XN) and 8-prenylnaringenin (8PN), is one of the most important prenylflavonoids found in hops. Another natural source of this compound is a shrub Sophora flavescens, used in traditional Chinese medicine. Main dietary source of IXN is beer, and the compound is produced from XN during wort boiling. In the human body, the compound is O-demethylated to 8PN, the strongest known phytoestrogen. This process takes place in the liver and in the intestine, where it is mediated by local microflora. It has been reported in some studies that even though beer contains small amounts of hops and its preparations, these compounds may affect the functioning of the human body. IXN exhibits an antiproliferative activity against human cell lines typical for breast cancer (MCF-7), ovarian cancer (A-2780), prostate cancer (DU145 and PC-3), and colon cancer (HT-29 and SW620) cells. It strongly inhibits the activation of the following carcinogens: 2-amino-3-methylimidazol-[4,5-f]quinoline and aflatoxin B1 (AFB1) via human cytochrome P450 (CYP1A2). It also inhibits the production of prostate specific antigen (PSA). IXN significantly reduces the expression of transforming growth factor-? (TGF-?) in the case of invasive breast cancer MDA-MB-231. It interferes with JAK/STAT signaling pathway and inhibits the expression of pro1inflammatory genes in the monoblastic leukemia cell line (MonoMac6). It activates apoptosis in human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMCs). In addition, IXN shows an antiviral activity towards herpes viruses (HSV1 and HSV2) and bovine viral diarrhea virus (BVDV). PMID:25771121

  6. Soil moisture pre-treatment effects on enzyme activities as indicators of heavy metal-contaminated and reclaimed soils

    Microsoft Academic Search

    M. Belén Hinojosa; José A. Carreira; Roberto García-Ruíz; Richard P. Dick

    2004-01-01

    Heavy metal contamination can inhibit soil functions but it is often difficult to determine the degree of pollution or when soil reclamation is complete. Enzyme assays offer potential as indicators of biological functioning of soils. However, antecedent water content of soil samples may affect the outcome of biological measurements. In Mediterranean regions, for much of the year ‘field moist’ surface

  7. Soil drainage as an active agent of recent soil evolution: a David Montagnea,b

    E-print Network

    Boyer, Edmond

    1 Soil drainage as an active agent of recent soil evolution: a review* David Montagnea,b , Sophie Cornua , Lydie Le Forestierc , Isabelle Cousina a INRA-UR 0272, Unité de Science du Sol, centre de on pedogenesis mainly focuses on the long-term soil formation and most often neglects recent soil evolution

  8. Applied Soil Ecology 24 (2003) 263271 Soil microbial activity in a Liquidambar plantation unresponsive

    E-print Network

    Neher, Deborah A.

    2003-01-01

    Applied Soil Ecology 24 (2003) 263­271 Soil microbial activity in a Liquidambar plantation. / Applied Soil Ecology 24 (2003) 263­271 These carbon inputs have been shown to stimulate microbial the potential to alter nutrient availability and soil carbon storage. We measured fine root density, microbial

  9. Seed, soil, and beyond: The basic biology of brain metastasis

    PubMed Central

    Ramakrishna, Rohan; Rostomily, Robert

    2013-01-01

    First invoked by Paget, the seed and soil hypothesis suggests that the successful growth of metastatic cells depends on the interactions and properties of cancer cells (seeds) and their potential target organs (soil). In the context of the seed and soil hypothesis this review examines recent advances in the understanding of molecular and cellular features that permit transformed epithelial cells to gain access to the blood stream (intravasation), survive their journey through the blood stream, and ultimately traverse through the microvasculature of target organs (extravsation) to deposit, survive, and grow in a foreign tissue environment. In addition to a review of the clinical and experimental evidence supporting the seed and soil theory to cancer metastasis, additional concepts highlighted include: (i) The role of cancer stem-like cells as putative cells of metastatic origin (the “seeds”); (ii) the mechanism of epithelial to mesenchymal transition (EMT) in driving epithelial cell conthose molecules do no blood stream to avoid anoikis, or anchorage independent cell death; and (iv) the reverse process of EMT, or mesenchymal to epithelial transition (MET), which promotes conversion back to the parent cell morphology and growth of macrometastsis in the target organ. The unique biology of metastases once established in the brain, and in particular the “sanctuary” role that the brain microenvironment plays in promoting metastatic growth and treatment resistance, will also be examined. These issues are of more than academic interest since as systemic therapies gradually improve local tumor control, the relative impact of brain metastasis will inexorably play a proportionally greater role in determining patient morbidity and mortality. PMID:23717797

  10. Elsholtzia: phytochemistry and biological activities

    PubMed Central

    2012-01-01

    Plants of the genus Elsholtzia (Lamiaceae) have a long history of medicinal use in folk. The phytochemical investigations revealed the presence of flavonoids, phenylpropanoids, terpenoids, and other compounds. Abundant volatile components are also identified. Pure compounds, volatile constituents and crude extracts from the genus exhibited a wide spectrum of in vitro and in vivo pharmacological activities. The aims of this review hopefully provide comprehensive information on the distribution, phytochemistry, volatile components, and pharmacological research of Elsholtzia for exploring the potential and advance researches. PMID:23216850

  11. Cyanobacterial Diversity in Biological Soil Crusts along a Precipitation Gradient, Northwest Negev Desert, Israel.

    PubMed

    Hagemann, Martin; Henneberg, Manja; Felde, Vincent J M N L; Drahorad, Sylvie L; Berkowicz, Simon M; Felix-Henningsen, Peter; Kaplan, Aaron

    2015-07-01

    Cyanobacteria occur worldwide but play an important role in the formation and primary activity of biological soil crusts (BSCs) in arid and semi-arid ecosystems. The cyanobacterial diversity in BSCs of the northwest Negev desert of Israel was surveyed at three fixed sampling stations situated along a precipitation gradient in the years 2010 to 2012. The three stations also are characterized by marked differences in soil features such as soil carbon, nitrogen, or electrical conductivity. The cyanobacterial biodiversity was analyzed by sequencing inserts of clone libraries harboring partial 16S rRNA gene sequences obtained with cyanobacteria-specific primers. Filamentous, non-diazotrophic strains (subsection III), particularly Microcoleus-like, dominated the cyanobacterial community (30 % proportion) in all years. Specific cyanobacterial groups showed increased (e.g., Chroococcidiopsis, Leptolyngbya, and Nostoc strains) or decreased (e.g., unicellular strains belonging to the subsection I and Scytonema strains) abundances with declining water availability at the most arid, southern station, whereas many cyanobacterial strains were frequently found in the soils of all three stations. The cyanobacterial diversity at the three sampling stations appears dependent on the available precipitation, whereas the differences in soil chemistry were of lower importance. PMID:25408227

  12. Field management effects on soil enzyme activities

    Microsoft Academic Search

    Anna K. Bandick; Richard P. Dick

    1999-01-01

    There is growing recognition for the need to develop sensitive indicators of soil quality that reflect the effects of land management on soil and assist land managers in promoting long-term sustainability of terrestrial ecosystems. Eleven soil enzymes assays were investigated relative to soil management and soil quality at two study sites. Soils were sampled from the Vegetable Crop Rotation Plots

  13. Short term recovery of soil biological functions in a new vineyard cultivated in organic farming

    NASA Astrophysics Data System (ADS)

    Costantini, Edoardo; Agnelli, Alessandro; Fabiani, Arturo; Gagnarli, Elena; Mocali, Stefano; Priori, Simone; Simoni, Sauro; Valboa, Giuseppe

    2014-05-01

    Deep earthwork activities carried out before vineyard plantation completely upset soil profile and characteristics. The resulting soil features are often much more similar to the underlying substratum than original soil profile. The time needed to recover soil functions is ecologically relevant and affects vine phenology and grape yield, particularly in organic viticulture. The general aim of this research work was to investigate the time needed to recover soil functions after the earthworks made before vine plantation. This study compared for a four years period physical and chemical properties, microbial and mesofauna communities, in new and old vineyards, cultivated on the same soil type. The experiment was conducted in a farm of the Chianti Classico district (Central Italy), on hills of high altitude (400-500 m a.s.l.) on clayey-calcareous flysches, with stony and calcareous soils (Haplic Cambisol (Calcaric, Skeletic)). The reference vine cultivar was Sangiovese. The older vineyard was planted in 2000, after slope reshaping by bulldozing and back hoe ploughing down to about 0.8-1.0 m. The new vineyard was planted in 2011 after an equivalent earthwork carried out in the summer of 2009. Both vineyards were organically managed and only compost at the rate of 1,000 kg ha-1 -a was added every year. The new vineyard was periodically cultivated by mechanical tillage, while the older only at alternate rows. Soil samples from the first 15 cm depth were collected in 4 replicates in the younger as well as in the older vineyard during the springtime of 2010-2013; in the older vineyard, two samples were from the periodically cultivated swaths and two under permanent grass cover. Samples were analysed for physical (particle size, field capacity, wilting point), chemical (pH, electrical conductivity, lime, active lime, organic carbon, total nitrogen), microbiological (soil respiration, microbial biomass, DGGE), and mesofauna features (abundance, taxa richness, BSQ index and soil biological classes). Physical soil characteristics remained unchanged after the first year from the earthworks and did not change under grass cover. Chemical analysis only indicated a significant effect of earthworks. Over the 2010-2013 period, the new vineyard showed a slight increase of TOC and total N contents; as compared to the old vineyard, it averaged lower TOC and total N, and higher CaCO3 contents, suggesting still evolving equilibrium conditions. Microarthropod analysis showed significant different abundances and communities' structures both by management system and by year, increasing where the land use pressure was reduced by permanent grass cover and along with the aging of vineyard. Though the euedaphic forms, well adapted to soil life, were always rare. Microbiological analysis showed a different structure of eubacterial communities and a lower microbial activity in the new vineyard, especially during 2010-2012. In contrast, significant differences were not observed between the two vineyards in 2013, and grass cover effect was controversial. To sum up, the consequence of deep earthworks on chemical and biological properties were still evident after four years from planting and more time was needed to recover soil functions. Permanent grass cover did not always show a consistent positive effect.

  14. Specific biological activities of Chinese lacquer polysaccharides

    Microsoft Academic Search

    R Lu; T Yoshida; H Nakashima; M Premanathan; R Aragaki; T Mimura; Y Kaneko; N Yamamoto; T Miyakoshi; T Uryu

    2000-01-01

    The specific biological activities such as blood coagulant, anti-tumor, anti-HIV, and anticoagulant activities of a Chinese lacquer polysaccharide, a branched acidic polysaccharide, before and after sulfonation were investigated. The lacquer polysaccharide at a concentration of 0.016mg\\/ml was found to shorten the coagulation time of bovine plasma more than 1min by comparison with that of a blank, 5min and 25s, suggesting

  15. Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles

    PubMed Central

    Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

    2012-01-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

  16. Biological soil crust succession impact on soil moisture and temperature in the sub-surface along a rainfall gradient

    NASA Astrophysics Data System (ADS)

    Zaady, E.; Yizhaq, H.; Ashkenazy, Y.

    2012-04-01

    Biological soil crusts produce mucilage sheets of polysaccharides that cover the soil surface. This hydrophobic coating can seal the soil micro-pores and thus cause reduction of water permeability and may influence soil temperature. This study evaluates the impact of crust composition on sub-surface water and temperature over time. We hypothesized that the successional stages of biological soil crusts, affect soil moisture and temperature differently along a rainfall gradient throughout the year. Four experimental sites were established along a rainfall gradient in the western Negev Desert. At each site three treatments; crust removal, pure sand (moving dune) and natural crusted were monitored. Crust successional stage was measured by biophysiological and physical measurements, soil water permeability by field mini-Infiltrometer, soil moisture by neutron scattering probe and temperature by sensors, at different depths. Our main interim conclusions from the ongoing study along the rainfall gradient are: 1. the biogenic crust controls water infiltration into the soil in sand dunes, 2. infiltration was dependent on the composition of the biogenic crust. It was low for higher successional stage crusts composed of lichens and mosses and high with cyanobacterial crust. Thus, infiltration rate controlled by the crust is inverse to the rainfall gradient. Continuous disturbances to the crust increase infiltration rates, 3. despite the different rainfall amounts at the sites, soil moisture content below 50 cm is almost the same. We therefore predict that climate change in areas that are becoming dryer (desertification) will have a positive effect on soil water content and vice versa.

  17. Vulnerability of desert biological soil crusts to wind erosion: the influences of crust development, soil texture, and disturbance

    Microsoft Academic Search

    Jayne Belnap; Dale A. Gillette

    1998-01-01

    Biological soil crusts, consisting of cyanobacteria, green algae, lichens, and mosses, are important in stabilizing soils in semi-arid and arid lands. Integrity of these crusts is compromised by compressional disturbances such as foot, vehicle, or livestock traffic. Using a portable wind tunnel, we found threshold friction velocities (TFVs) of undisturbed crusts well above wind forces experienced at these sites; consequently,

  18. Effects of electrokinetic treatment of a heavy metal contaminated soil on soil enzyme activities

    Microsoft Academic Search

    Long Cang; Dong-Mei Zhou; Quan-Ying Wang; Dan-Ya Wu

    2009-01-01

    There is a growing concern on the potential application of a direct current (DC) electric field to soil for removing contaminants, but little is known about its impact on soil enzyme activities. This study investigated the change of enzyme activities of a heavy metal contaminated soil before and after electrokinetic (EK) treatments at lab-scale and the mechanisms of EK treatment

  19. The effect on methane emission by different soil enzyme activity in paddy soil

    Microsoft Academic Search

    Jing Ling; Liangji Deng; Xiaolin Huang; Yan Li; Gan Jiang

    2011-01-01

    In this study, with the paddy soil by different fertilized in Chengdu Plain, we have researched the correlation between soil cataloes, phosphates and unease activity and CH4 emission. The results showed that: (1) in the rice growth period, the Soil cataloes, phosphates and unease activity for each treatment got the trend that decreasing first and then increasing, decreasing finally. The

  20. Remote sensing of biological soil crust under simulated climate change manipulations in the Mojave Desert

    Microsoft Academic Search

    Susan L. Ustin; Phillip G. Valko; Shawn C. Kefauver; Maria J. Santos; Jeff F. Zimpfer; Stanley D. Smith

    2009-01-01

    Earth's arid and semiarid ecosystems are subject to novel combinations of disruptive factors and unprecedented rates of change. Biotic soil crust is believed to be sensitive to impacts caused by land use and climate changes. This study examined the potential for spectral detection of different biological soil crusts (BSC: cyanobacteria, moss and lichen) and bare soil components at a long-term

  1. Soil Biology & Biochemistry 38 (2006) 16081614 Endogeic earthworms differentially influence bacterial communities

    E-print Network

    Rilli, Matthias C.

    2006-01-01

    C. Rilliga , Johan Sixb a Division of Biological Sciences, Microbial Ecology Program, The University-facilitated aggregate formation, how and where within the soil matrix earthworm-facilitated influences on soil microbial, the extent to which microbial communities associated with different soil microhabitats are affected is

  2. Effects of cadium, zinc and lead on soil enzyme activities

    Microsoft Academic Search

    Zhi-xin YANG; Shu-qing LIU; Da-wei ZHENG; Sheng-dong FENG

    2006-01-01

    Heavy metal (HM) is a major hazard to the soil-plant system. This study investigated the combined effects of cadium (Cd), zinc (Zn) and lead (Pb) on activities of four enzymes in soil, including calatase, urease, invertase and alkalin phosphatase. HM content in tops of canola and four enzymes activities in soil were analyzed at two months after the metal additions

  3. Activity of soil bacteria on petroleum waste adjacent to an active oil well

    Microsoft Academic Search

    R. E. Cooper; H. G. Hedrick

    1976-01-01

    Activity of four soil bacterial isolates from soils adjacent to an active oil well located in north central Louisiana was determined. Viable cell counts, shake-culture growths, gaseous evolution in soil samples impregnated with petroleum waste, and manometric experiments on oxygen uptake with selected hydrocarbons were used as measurements of activity of the soil bacteria on the petroleum waste. Of ten

  4. Soil nutrient and soil enzyme activity at various types of slopes in disturbed area of Xiangjiaba hydropower construction

    Microsoft Academic Search

    Dong Xia; Wen-nian Xu; Juan Zhao; Shun-Bo Zhu

    2011-01-01

    Taking seven types of slopes in the disturbed area of Xiangjiaba construction as test objects this paper measured their soil pH, soil nutrient and soil enzyme activity. The results showed that the soil at natural forests (NF) was acidic, while the others were weakly alkaline at different degree. Variation of soil nutrients in different slopes is obvious; soil enzyme activity

  5. Development, calibration, and performance of a novel biocrust wetness probe (BWP) measuring the water content of biological soil crusts and surface soils

    NASA Astrophysics Data System (ADS)

    Weber, Bettina; Berkemeier, Thomas; Ruckteschler, Nina; Caesar, Jennifer; Ritter, Holger; Heintz, Henno; Brass, Henning

    2015-04-01

    The surface layer of soils as transition zone between pedosphere and atmosphere plays a crucial role in exchange processes of nutrients, atmospheric gases and water. In arid and semiarid regions, this uppermost soil layer is commonly colonized by biological soil crusts (biocrusts), which cover about 46 million km2 worldwide being highly relevant in the global terrestrial carbon and nitrogen cycles. Their water status is of major concern, as activity of these poikilohydric organisms is directly controlled by their water content. On-site analyses of both bare and crusted soils thus are urgently needed to correctly model exchange processes of water, nutrients and trace gases at the soil surface. In this study we present the biocrust wetness probe (BWP), which is the first low-cost sensor to reliably measure the water content within biocrusts or the uppermost 5 mm of the substrate. Using a weak alternating current, the electrical conductivity is assessed and an automatic calibration routine allows calculating the water content and precipitation equivalent of the surface layer over time. During one year of continuous field measurements, 60 BWPs were installed in different types of biocrusts and bare soil to measure at 5-minute intervals in the Succulent Karroo, South Africa. All sensors worked reliably and responded immediately and individually upon precipitation events. Upon completion of field measurements, soil and biocrust samples were collected from all measurement spots to compile calibration curves in the lab. In most soil and biocrust samples the water content rose linearly with increasing electrical conductivity values and only for few samples an exponential relationship was observed. Measurements revealed characteristic differences in biocrust and soil wetness patterns, which affect both the water regime and physiological processes in desert regions. Thus BWPs turned out to be well suited sensors for spatio-temporal monitoring of soil water content, allowing for modeling of soil water fluxes, nutrient allocation and growth.

  6. Carbon and nitrogen fixation differ between successional stages of biological soil crusts in the Colorado Plateau and Chihuahuan Desert

    USGS Publications Warehouse

    Housman, D.C.; Powers, H.H.; Collins, A.D.; Belnap, J.

    2006-01-01

    Biological soil crusts (cyanobacteria, mosses and lichens collectively) perform essential ecosystem services, including carbon (C) and nitrogen (N) fixation. Climate and land-use change are converting later successional soil crusts to early successional soil crusts with lower C and N fixation rates. To quantify the effect of such conversions on C and N dynamics in desert ecosystems we seasonally measured diurnal fixation rates in different biological soil crusts. We classified plots on the Colorado Plateau (Canyonlands) and Chihuahuan Desert (Jornada) as early (Microcoleus) or later successional (Nostoc/Scytonema or Placidium/Collema) and measured photosynthesis (Pn), nitrogenase activity (NA), and chlorophyll fluorescence (Fv/Fm) on metabolically active (moist) soil crusts. Later successional crusts typically had greater Pn, averaging 1.2-1.3-fold higher daily C fixation in Canyonlands and 2.4-2.8-fold higher in the Jornada. Later successional crusts also had greater NA, averaging 1.3-7.5-fold higher daily N fixation in Canyonlands and 1.3-25.0-fold higher in the Jornada. Mean daily Fv/Fm was also greater in later successional Canyonlands crusts during winter, and Jornada crusts during all seasons except summer. Together these findings indicate conversion of soil crusts back to early successional stages results in large reductions of C and N inputs into these ecosystems.

  7. Biologically active compounds from Aphyllophorales (polypore) fungi.

    PubMed

    Zjawiony, Jordan K

    2004-02-01

    This review describes biologically active natural products isolated from Aphyllophorales, many of which are known as polypores. Polypores are a large group of terrestrial fungi of the phylum Basdiomycota (basidiomycetes), and they along with certain Ascomycota are a major source of pharmacologically active substances. There are about 25 000 species of basidiomycetes, of which about 500 are members of the Aphyllophorales, a polyphyletic group that contains the polypores. Many of these fungi have circumboreal distributions in North America, Europe, and Asia and broad distributions on all inhabited continents and Africa; only a small number of the most common species with the most obvious fruiting bodies (basidiocarps) have been evaluated for biological activity. An estimated 75% of polypore fungi that have been tested show strong antimicrobial activity, and these may constitute a good source for developing new antibiotics. Numerous compounds from these fungi also display antiviral, cytotoxic, and/or antineoplastic activities. Additional important components of this vast arsenal of compounds are polysaccharides derived from the fungal cell walls. These compounds have attracted significant attention in recent years because of their immunomodulatory activities, resulting in antitumor effects. These high molecular weight compounds, often called biological response modifiers (BRM), or immunopotentiators, prevent carcinogenesis, show direct anticancer effects, and prevent tumor metastasis. Some of the protein-bound polysaccharides from polypores and other basidiomycetes have found their way to the market in Japan as anticancer drugs. Finally, numerous compounds with cardiovascular, phytotoxic, immunomodulatory, analgesic, antidiabetic, antioxidant, insecticidal, and nematocidal activities, isolated from polypores, are also presented. In fact many of the fungi mentioned in this paper have long been used in herbal medicine, including polypores such as Ganoderma lucidum (Reishi or Ling Zhi), Laetiporus sulphureus (Chicken-of-the-Woods), Trametes versicolor (Yun Zhi), Grifola umbellata (Zhu Lin), Inonotus obliquus (Chaga), and Wolfiporia cocos (Hoelen). PMID:14987072

  8. Effect of soil type and soil management on soil physical, chemical and biological properties in commercial organic olive orchards in Southern Spain

    NASA Astrophysics Data System (ADS)

    Gomez, Jose Alfonso; Auxiliadora Soriano, Maria; Montes-Borrego, Miguel; Navas, Juan Antonio; Landa, Blanca B.

    2014-05-01

    One of the objectives of organic agriculture is to maintain and improve soil quality, while simultaneously producing an adequate yield. A key element in organic olive production is soil management, which properly implemented can optimize the use of rainfall water enhancing infiltration rates and controlling competition for soil water by weeds. There are different soil management strategies: eg. weed mowing (M), green manure with surface tillage in spring (T), or combination with animal grazing among the trees (G). That variability in soil management combined with the large variability in soil types on which organic olive trees are grown in Southern Spain, difficult the evaluation of the impact of different soil management on soil properties, and yield as well as its interpretation in terms of improvement of soil quality. This communications presents the results and analysis of soil physical, chemical and biological properties on 58 soils in Southern Spain during 2005 and 2006, and analyzed and evaluated in different studies since them. Those 58 soils were sampled in 46 certified commercial organic olive orchards with four soil types as well as 12 undisturbed areas with natural vegetation near the olive orchards. The four soil types considered were Eutric Regosol (RGeu, n= 16), Eutric Cambisol (CMeu, n=16), Calcaric Regosol (RGca, n=13 soils sampled) and Calcic Cambisol (CMcc), and the soil management systems (SMS) include were 10 light tillage (LT), 16 sheep grazing (G), 10 tillage (T), 10 mechanical mowing (M), and 12 undisturbed areas covered by natural vegetation (NV-C and NV-S). Our results indicate that soil management had a significant effect on olive yield as well as on key soil properties. Among these soil properties are physical ones, such as infiltration rate or bulk density, chemical ones, especially organic carbon concentration, and biological ones such as soil microbial respiration and bacterial community composition. Superimpose to that soil management induced variability, there was a strong interaction with soil type and climate conditions. There was also a relatively high variability within the same soil management and soil type class, indicating farm to farm variability in conditions and history of soil management. Based on this dataset two different approaches were taken to: A) evaluate the risk of soil degradation based on a limited set of soil properties, B) assess the effect of changes in SMS on soil biodiversity by using terminal restriction profiles (TRFs) derived from T-RFLP analysis of amplified 16S rDNA as. The results indicates the potential of both approaches to assess the risk of soil degradation (A) and the impact on soil biodiversity (B) upon appropriate benchmarking to characterize the interaction between soil management and soil type References Álvarez, S., Soriano, M.A., Landa, B.B., and Gómez, J.A. 2007. Soil properties in organic olive orchards compared with that in natural areas in a mountainous landscape in southern Spain. Soil Use Manage 23:404-416. Gómez, J.A., Álvarez, S., and Soriano, M.A. 2009. Development of a soil degradation assessment tool for organic olive groves in southern Spain. Catena 79:9-17. Landa, B.B., Montes-Borrego, M., Aranda, S., Soriano, M.A., Gómez, J.A., and Navas-Cortés, J.A. 2013. Soil factors involved in the diversity and structure of soil bacterial communities in commercial organic olive orchards in Southern Spain. Environmental Microbiology Reports (accepted) Soriano, M.A., Álvarez, S., Landa, B.B., and Gómez, J.A. 2013. Soil properties in organic olive orchards following different weed management in a rolling landscape of Andalusia, Spain. Renew Agr Food Syst (in press), doi:10.1017/S1742170512000361.

  9. Soil enzyme activities as affected by anthropogenic alterations: intensive agricultural practices and organic pollution

    Microsoft Academic Search

    Liliana Gianfreda; Maria Antonietta Rao; Anna Piotrowska; Giuseppe Palumbo; Claudio Colombo

    2005-01-01

    The activity of a range of enzymes related to the cycling of the main biologically important nutrients C, N, P and S was investigated in cultivated and non-cultivated soils from various parts of Europe. Two agricultural sites from North Italy under continuous corn (Zea mays L.) with and without organic fertilization were compared. Two other agricultural sites from South Italy

  10. Monitoring Biological Activity at Geothermal Power Plants

    SciTech Connect

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  11. Perspectives on Biologically Active Camptothecin Derivatives.

    PubMed

    Liu, Ying-Qian; Li, Wen-Qun; Morris-Natschke, Susan L; Qian, Keduo; Yang, Liu; Zhu, Gao-Xiang; Wu, Xiao-Bing; Chen, An-Liang; Zhang, Shao-Yong; Nan, Xiang; Lee, Kuo-Hsiung

    2015-07-01

    Camptothecins (CPTs) are cytotoxic natural alkaloids that specifically target DNA topoisomerase I. Research on CPTs has undergone a significant evolution from the initial discovery of CPT in the late 1960s through the study of synthetic small-molecule derivatives to investigation of macromolecular constructs and formulations. Over the past years, intensive medicinal chemistry efforts have generated numerous CPT derivatives. Three derivatives, topotecan, irinotecan, and belotecan, are currently prescribed as anticancer drugs, and several related compounds are now in clinical trials. Interest in other biological effects, besides anticancer activity, of CPTs is also growing exponentially, as indicated by the large number of publications on the subject during the last decades. Therefore, the main focus of the present review is to provide an ample but condensed overview on various biological activities of CPT derivatives, in addition to continued up-to-date coverage of anticancer effects. PMID:25808858

  12. Simultaneous analysis of biologically active aminoalkanephosphonic acids

    Microsoft Academic Search

    Zbigniew H Kudzin; Dorota K Gralak; Grzegorz Andrijewski; Józef Drabowicz; Jerzy ?uczak

    2003-01-01

    A new approach for simultaneous analysis of biologically active aminoalkanephosphonic acids, namely glyphosate, phosphonoglycine, phosphonosarcosine, phosphonoalanine, phosphono-?-alanine, phosphonohomoalanine, phosphono-?-homoalanine and glufosinate, is presented. This includes a preliminary 31P NMR analysis of these amino acids, their further derivatization to volatile phosphonates (phosphinates) by means of trifluoroacetic acid–trifluoroacetic anhydride–trimethyl orthoacetate reagent and subsequent analysis of derivatization products using MS and\\/or GC–MS (chemical

  13. Generation and Biological Activities of Oxidized Phospholipids

    PubMed Central

    Oskolkova, Olga V.; Birukov, Konstantin G.; Levonen, Anna-Liisa; Binder, Christoph J.; Stöckl, Johannes

    2010-01-01

    Abstract Glycerophospholipids represent a common class of lipids critically important for integrity of cellular membranes. Oxidation of esterified unsaturated fatty acids dramatically changes biological activities of phospholipids. Apart from impairment of their structural function, oxidation makes oxidized phospholipids (OxPLs) markers of “modified-self” type that are recognized by soluble and cell-associated receptors of innate immunity, including scavenger receptors, natural (germ line-encoded) antibodies, and C-reactive protein, thus directing removal of senescent and apoptotic cells or oxidized lipoproteins. In addition, OxPLs acquire novel biological activities not characteristic of their unoxidized precursors, including the ability to regulate innate and adaptive immune responses. Effects of OxPLs described in vitro and in vivo suggest their potential relevance in different pathologies, including atherosclerosis, acute inflammation, lung injury, and many other conditions. This review summarizes current knowledge on the mechanisms of formation, structures, and biological activities of OxPLs. Furthermore, potential applications of OxPLs as disease biomarkers, as well as experimental therapies targeting OxPLs, are described, providing a broad overview of an emerging class of lipid mediators. Antioxid. Redox Signal. 12, 1009–1059. PMID:19686040

  14. Effects of biological weathering on mine soil genesis and fertility

    Microsoft Academic Search

    1981-01-01

    Strip mine spoils derived from overburden rocks of the Pennsylvanian Wise Formation in Buchanan County, Virginia, commonly contain 40% less than 2 mm sized soil material. The physical and chemical properties of these soil materials are related to their rock origin. The soil materials are alkaline due to the presence of carbonates. The principal source of P in the soil

  15. Smectite clays in Mars soil - Evidence for their presence and role in Viking biology experimental results

    NASA Technical Reports Server (NTRS)

    Banin, A.; Rishpon, J.

    1979-01-01

    Evidence for the presence of smectite clays in Martian soils is reviewed and results of experiments with certain active clays simulating the Viking biology experiments are reported. Analyses of Martian soil composition by means of X-ray fluorescence spectrometry and dust storm spectroscopy and Martian geological history strongly suggest the presence of a mixture of weathered ferro-silicate minerals, mainly nontronite and montmorillonite, accompanied by soluble sulphate salts, as major constituents. Samples of montmorillonite and nontronite incubated with (C-14)-formate or the radioactive nutrient medium solution used in the Viking Labeled Release experiment, were found to produce patterns of release of radioactive gas very similar to those observed in the Viking experiments, indicating the iron-catalyzed decomposition of formate as the reaction responsible for the Viking results. The experimental results of Hubbard (1979) simulating the results of the Viking Pyrolytic Release experiment using iron montmorillonites are pointed out, and it is concluded that many of the results of the Viking biology experiments can be explained in terms of the surface activity of smectite clays in catalysis and adsorption.

  16. Increased temperature and altered summer precipitation have differential effects on biological soil crusts in a dryland ecosystem

    USGS Publications Warehouse

    Johnson, Shannon L.; Kuske, Cheryl R.; Carney, Travis D.; Housman, David C.; Gallegos-Graves, La Verne; Belnap, Jayne

    2012-01-01

    Biological soil crusts (biocrusts) are common and ecologically important members of dryland ecosystems worldwide, where they stabilize soil surfaces and contribute newly fixed C and N to soils. To test the impacts of predicted climate change scenarios on biocrusts in a dryland ecosystem, the effects of a 2–3 °C increase in soil temperature and an increased frequency of smaller summer precipitation events were examined in a large, replicated field study conducted in the cold desert of the Colorado Plateau, USA. Surface soil biomass (DNA concentration), photosynthetically active cyanobacterial biomass (chlorophyll a concentration), cyanobacterial abundance (quantitative PCR assay), and bacterial community composition (16S rRNA gene sequencing) were monitored seasonally over 2 years. Soil microbial biomass and bacterial community composition were highly stratified between the 0–2 cm depth biocrusts and 5–10 cm depth soil beneath the biocrusts. The increase in temperature did not have a detectable effect on any of the measured parameters over 2 years. However, after the second summer of altered summer precipitation pattern, significant declines occurred in the surface soil biomass (avg. DNA concentration declined 38%), photosynthetic cyanobacterial biomass (avg. chlorophyll a concentration declined 78%), cyanobacterial abundance (avg. gene copies g?1 soil declined 95%), and proportion of Cyanobacteria in the biocrust bacterial community (avg. representation in sequence libraries declined 85%). Biocrusts are important contributors to soil stability, soil C and N stores, and plant performance, and the loss or reduction of biocrusts under an altered precipitation pattern associated with climate change could contribute significantly to lower soil fertility and increased erosion and dust production in dryland ecosystems at a regional scale.

  17. Biological activity and tentative identification of flavonoid components in velvetleaf ( Abutilon theophrasti Medik.) seed coats

    Microsoft Academic Search

    Wojciech L. Paszkowski; Robert J. Kremer

    1988-01-01

    The biological activity of aqueous extracts of velvetleaf (Abutilontheophrasti Medik.) seed coats and their flavonoid components against three plant species and five soil fungi was investigated. Aqueous extracts slightly inhibited germination and significantly inhibited radicle growth of all plant species tested. Fungal growth was inhibited or not affected, depending on species, by aqueous extracts. The aqueous extracts were extracted into

  18. The soil moisture active passive experiments (SMAPEx): Towards soil moisture retrieval from the SMAP mission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NASA’s Soil Moisture Active Passive (SMAP) mission, scheduled for launch in 2014, will carry the first combined L-band radar and radiometer system with the objective of mapping near surface soil moisture and freeze/thaw state globally at near-daily time step (2-3 days). SMAP will provide three soil ...

  19. Accommodating Students with Disabilities in Soil Science Activities

    ERIC Educational Resources Information Center

    Langley-Turnbaugh, S. J.; Murphy, Kate; Levin, E.

    2004-01-01

    Soil science education is lacking in terms of accommodations for persons with disabilities. Individuals with disabilities are often excluded from soil science activities in school, and from soil science careers. GLOBE (Global Learning Observations to Benefit the Environment) is a worldwide, hands-on primary and secondary school-based education and…

  20. Variation in Soil Enzyme Activities in a Temperate Agroforestry Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Integration of agroforestry and grass buffers into row crop watersheds improves overall environmental quality, including soil quality. The objective of this study was to examine management and landscape effects on soil carbon, soil nitrogen, microbial diversity, enzyme activity, and DNA concentrati...

  1. Vulnerability of desert biological soil crusts to wind erosion: The influences of crust development, soil texture, and disturbance

    USGS Publications Warehouse

    Belnap, J.; Gillette, Dale A.

    1998-01-01

    Biological soil crusts, consisting of cyanobacteria, green algae, lichens, and mosses, are important in stabilizing soils in semi-arid and arid lands. Integrity of these crusts is compromised by compressional disturbances such as foot, vehicle, or livestock traffic. Using a portable wind tunnel, we found threshold friction velocities (TFVs) of undisturbed crusts well above wind forces experienced at these sites; consequently, these soils are not vulnerable to wind erosion. However, recently disturbed soils or soils with less well-developed crusts frequently experience wind speeds that exceed the stability thresholds of the crusts. Crustal biomass is concentrated in the top 3 mm of soils. Sandblasting by wind can quickly remove this material, thereby reducing N and C inputs from these organisms. This loss can result in reduced site productivity, as well as exposure of unprotected subsurface sediments to wind and water erosion. Actions to reduce impacts to these crusts can include adjustments in type, intensity, and timing of use.

  2. Rehabilitation of European Biological Soil Crusts - The SCIN project

    NASA Astrophysics Data System (ADS)

    Williams, Laura; Zheng, Lingjuan; Maier, Stefanie; Weber, Bettina; Büdel, Burkhard

    2015-04-01

    The ''Soil Crust INternational'' (SCIN) Project aims to improve the appreciation and understanding of European Biological Soil Crusts (BSC) with the goal of developing biodiversity conservation and sustainable management strategies. Our objective is to study the uniqueness of European BSC on a local scale and investigate how these communities thrive in areas with such great macroclimatic differences. In order to cover a wide diversity of European BSC a latitudinal transect was established, extending from the Great Alvar of Öland, Sweden in the north, down to Gössenheim, Central Germany and Hochtor in the Hohe Tauern National Park, Austria, continuing to the Badlands of Tabernas, in southern Spain. The transect stretches over 20° latitude and 2,300 m in altitude and includes natural and also semi-natural sites that require maintenance, for instance, by grazing. Within the SCIN project a rehabilitation study was initiated in order to investigate the recovery potential of BSC under different environmental conditions. This entailed the construction of 10 times 1m2 plots, alongside control plots, at each of the 4 sites, where the BSC was completely removed. Over the course of 2 years (2012-2014) the plots were sampled regularly to assess recovery in the form of returning organisms (cyanobacteria, algae, lichens, bryophytes, higher plants), soil stability, chlorophyll and carbon content and nutrient composition. Cyanobacteria are considered as the pioneering functional group of BSC establishment in many regions, especially arid, and may be critical for the successful formation of any of the further BSC successional stages. Therefore, the cyanobacterial assemblages of recovering plots are being investigated to shed light on the importance of cyanobacteria in the rehabilitation of BSC and whether individual species or specific communities can be ascribed to a local or wide geographical range. It also has to be considered the proximity of recovering BSC to established crust; in our case a major contributing factor to successful recovery has to be the mature BSC surrounding the plots. Our results so far show however, that this may not be as simple as it seems due to the physical properties of the treated plot, the erosion caused by the lack of BSC may severely affect the ability of returning communities to establish themselves, and therefore the geographical and climatic aspects of the rehabilitation sites play a crucial factor in the sense of minimising erosion as much as possible. Two years is clearly not a significant amount of time in the rehabilitation of BSC, but this study throws light on the initial stages of recovery and can suggest management practices for future rehabilitation projects.

  3. Community level physiological profiles (CLPP), characterization and microbial activity of soil amended with dairy sewage sludge.

    PubMed

    Fr?c, Magdalena; Oszust, Karolina; Lipiec, Jerzy

    2012-01-01

    The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha(-1) and 26 Mg·ha(-1)) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon-Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments. PMID:22737006

  4. Community Level Physiological Profiles (CLPP), Characterization and Microbial Activity of Soil Amended with Dairy Sewage Sludge

    PubMed Central

    Fr?c, Magdalena; Oszust, Karolina; Lipiec, Jerzy

    2012-01-01

    The aim of the present work was to assess the influence of organic amendment applications compared to mineral fertilization on soil microbial activity and functional diversity. The field experiment was set up on a soil classified as an Eutric Cambisol developed from loess (South-East Poland). Two doses of both dairy sewage sludge (20 Mg·ha?1 and 26 Mg·ha?1) and of mineral fertilizers containing the same amount of nutrients were applied. The same soil without any amendment was used as a control. The soil under undisturbed native vegetation was also included in the study as a representative background sample. The functional diversity (catabolic potential) was assessed using such indices as Average Well Color Development (AWCD), Richness (R) and Shannon–Weaver index (H). These indices were calculated, following the community level physiological profiling (CLPP) using Biolog Eco Plates. Soil dehydrogenase and respiratory activity were also evaluated. The indices were sensitive enough to reveal changes in community level physiological profiles due to treatment effects. It was shown that dairy sewage amended soil was characterized by greater AWCD, R, H and dehydrogenase and respiratory activity as compared to control or mineral fertilized soil. Analysis of variance (ANOVA) and principal component analysis (PCA) were used to depict the differences of the soil bacterial functional diversity between the treatments. PMID:22737006

  5. Seasonal Variation in Soil Microbial Biomass, Bacterial Community Composition and Extracellular Enzyme Activity in Relation to Soil Respiration in a Northern Great Plains Grassland

    NASA Astrophysics Data System (ADS)

    Wilton, E.; Flanagan, L. B.

    2014-12-01

    Soil respiration rate is affected by seasonal changes in temperature and moisture, but is this a direct effect on soil metabolism or an indirect effect caused by changes in microbial biomass, bacterial community composition and substrate availability? In order to address this question, we compared continuous measurements of soil and plant CO2 exchange made with an automatic chamber system to analyses conducted on replicate soil samples collected on four dates during June-August. Microbial biomass was estimated from substrate-induced respiration rate, bacterial community composition was determined by 16S rRNA amplicon pyrosequencing, and ?-1,4-N-acetylglucosaminidase (NAGase) and phenol oxidase enzyme activities were assayed fluorometrically or by absorbance measurements, respectively. Soil microbial biomass declined from June to August in strong correlation with a progressive decline in soil moisture during this time period. Soil bacterial species richness and alpha diversity showed no significant seasonal change. However, bacterial community composition showed a progressive shift over time as measured by Bray-Curtis dissimilarity. In particular, the change in community composition was associated with increasing relative abundance in the alpha and delta classes, and declining abundance of the beta and gamma classes of the Proteobacteria phylum during June-August. NAGase showed a progressive seasonal decline in potential activity that was correlated with microbial biomass and seasonal changes in soil moisture. In contrast, phenol oxidase showed highest potential activity in mid-July near the time of peak soil respiration and ecosystem photosynthesis, which may represent a time of high input of carbon exudates into the soil from plant roots. This input of exudates may stimulate the activity of phenol oxidase, a lignolytic enzyme involved in the breakdown of soil organic matter. These analyses indicated that seasonal change in soil respiration is a complex interaction between temporal changes in soil environmental factors and biological changes in the plant and microbial community that affect soil respiratory metabolism.

  6. Evidence for biological mediation of K and P weathering inferred from a new process-based soil evolution model and soil chronosequences from Hawaii

    NASA Astrophysics Data System (ADS)

    Johnson, M.; Gloor, E.

    2012-12-01

    The productivity of many tropical forests is limited by the availability of nutrients such as phosphorus (P). Nutrient limitation thus has consequences for the global climate because it alters the response of vegetation productivity to changing CO2 concentrations. The amount of mineral derived nutrients available to vegetation depends upon a number of factors such as the age of the soil, the weatherability of rock minerals, the mechanism of nutrient uptake by the vegetation and the leaching intensity of the soils. An understanding of the interactions between pedogenetic processes and nutrient cycling can therefore enhance our understanding of ecosystem dynamics. Studies examining the interactions between soil processes and nutrient availability are limited, mainly because of the long timescales over which many of these processes operate and of the difficulty in isolating individual soil processes. Data from soil climate-sequences and chronosequences can potentially shed light on these interactions when combined with a model which includes soil forming processes over pedogenic timescales. We have developed a process-based soil evolution model which can be evaluated with measurements of soil properties in order to understand such biogeochemical cycles. The mechanistic, soil evolution model presented includes the major processes of soil formation including i) mineral weathering, ii) percolation of rainfall, iii) leaching of solutes, iv) surface erosion, v) bioturbation and vi) vegetation-soil interactions. The specific properties the model simulates over timescales of tens to hundreds of thousand years are, soil depth, vertical profiles of elemental composition, soil solution pH and organic carbon distribution. Modelled soil properties are compared with measured soil properties from basaltic soil chronosequences in Hawaii. The model generally agrees well with the soil chronosequences. Here we focus on one particularly interesting result regarding the role of the biosphere on weathering. Model results demonstrate that the biosphere greatly influences modelled soil properties. A good agreement is observed between measured and modelled Na, which is not a plant nutrient and Mg and Ca which are less strongly cycled, across both an age and rainfall gradient, suggesting a good understanding of modelled soil processes. However, the model underestimates the relative depletion of K and P from the soil profiles. Nutrient uptake in the model is controlled by the rate of evapotranspiration and the concentration of the nutrient in the soil solution. Independently, there is experimental evidence for roots actively inducing the release of non-exchangeable nutrients from minerals. The differences between measured and modelled K and P profiles therefore indirectly provides evidence for this mechanism of nutrient acquisition and highlights the important role vegetation and mycorrhiza play in accelerating the release of specific nutrients from minerals. This result suggests that biologically enhanced mineral weathering should be recognized when interpreting soil properties in order to understand soil-vegetation interactions.

  7. EFFECTS OF BIOLOGICAL AMENDMENTS ON SOIL MICROBIOLOGY AND SOILBORNE POTATO DISEASES IN DIFFERENT CROPPING SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various biological amendments, including commercial and research biocontrol agents, microbial inoculants, mycorrhizae, aerobic compost tea (ACT), and a biostimulant were evaluated for their effects on soil microbial community characteristics (SMCC) and soilborne diseases of potato in greenhouse and ...

  8. ADSORPTION, MOVEMENT, AND BIOLOGICAL DEGRADATION OF LARGE CONCENTRATIONS OF SELECTED PESTICIDES IN SOILS

    EPA Science Inventory

    Because of the importance of soil in biologically reducing the quantity and retarding the rate of pollutant movement into groundwater, this laboratory study was initiated to evaluate the adsorption, mobility, and degradation of large concentrations of the pesticide atrazine, meth...

  9. Recombinant glucagon: a differential biological activity.

    PubMed

    Basso, Angelina M M; Pelegrini, Patrícia B; Mulinari, Fernanda; Costa, Michelle C; Viana, Antonio B; Silva, Luciano P; Grossi-de-Sa, Maria Fatima

    2015-01-01

    In Brazil, there is a growing demand for specialised pharmaceuticals, and the high cost of their importation results in increasing costs, reaching US$ 1.34 billion in 2012 and US$ 1.61 billion in 2013. Worldwide expenses related to drugs could reach US$ 1.3 trillion in 2018, especially due to new treatments for hepatitis C and cancer. Specialised or high-cost pharmaceutical drugs used for the treatment of viral hepatitis, multiple sclerosis, HIV and diabetes are distributed free of charge by the Brazilian government. The glucagon peptide was included in this group of high-cost biopharmaceuticals in 2008. Although its main application is the treatment of hypoglycaemia in diabetic patients, it can also be used with patients in an alcoholic coma, for those patients with biliary tract pain, and as a bronchodilator. Therefore, in order to reduce biopharmaceutical production costs, the Brazilian government passed laws focusing on the development and increase of a National Pharmaceutical Industrial Centre, including the demand for the national production of glucagon. For that reason and given the importance and high cost of recombinant glucagon, the purpose of this study was to develop methods to improve production, purification and performance of the biological activity of recombinant glucagon. Glucagon was recombined into a plasmid vector containing a Glutathione S-transferase tag, and the peptide was expressed in a heterologous Escherichia coli system. After purification procedures and molecular analyses, the biological activity of this recombinant glucagon was examined using in vivo assays and showed a highly significant (p?biological activity. PMID:25852997

  10. Activity, adsorption, mobility and field persistence of sulfosulfuron in soil

    Microsoft Academic Search

    I. Eleftherohorinos; K. Dhima; I. Vasilakoglou

    2004-01-01

    Petri dish bioassays, based on root response of corn grown in soil or in perlite, were used to study the activity, adsorption,\\u000a mobility and field persistence of sulfosulfuron in a silty clay loam and a sandy loam soil. Both bioassays indicated that\\u000a activity of sulfosulfuron increased with increasing herbicide concentration, and to a slightly greater degree in sandy loam\\u000a soil

  11. Soil enzyme activities under agroforestry systems in northern Jiangsu Province

    Microsoft Academic Search

    Fuxu Wan; Ping Chen

    2004-01-01

    The authors presented the enzyme characteristics of catalase, sucrase, urease and alkaline phosphatase under agroforestry\\u000a systems in northern Jiangsu Province. The results show that soil enzyme activities reduce gradually from top to bottom layer\\u000a of the soil profile, and the fluctuations of catalase and urease are smaller than those of sucrase and alkaline phosphatase.\\u000a Soil enzyme activities differe significantly in

  12. The Soil Moisture Active Passive (SMAP) Applications Activity

    NASA Technical Reports Server (NTRS)

    Brown, Molly E.; Moran, Susan; Escobar, Vanessa; Entekhabi, Dara; O'Neill, Peggy; Njoku, Eni

    2011-01-01

    The Soil Moisture Active Passive (SMAP) mission is one of the first-tier satellite missions recommended by the U.S. National Research Council Committee on Earth Science and Applications from Space. The SMAP mission 1 is under development by NASA and is scheduled for launch late in 2014. The SMAP measurements will allow global and high-resolution mapping of soil moisture and its freeze/thaw state at resolutions from 3-40 km. These measurements will have high value for a wide range of environmental applications that underpin many weather-related decisions including drought and flood guidance, agricultural productivity estimation, weather forecasting, climate predictions, and human health risk. In 2007, NASA was tasked by The National Academies to ensure that emerging scientific knowledge is actively applied to obtain societal benefits by broadening community participation and improving means for use of information. SMAP is one of the first missions to come out of this new charge, and its Applications Plan forms the basis for ensuring its commitment to its users. The purpose of this paper is to outline the methods and approaches of the SMAP applications activity, which is designed to increase and sustain the interaction between users and scientists involved in mission development.

  13. Influence of metal oxide particles on soil enzyme activity and bioaccumulation of two plants.

    PubMed

    Kim, Sunghyun; Sin, Hyunjoo; Lee, Sooyeon; Lee, Insook

    2013-09-28

    Particle size and metal species are important to both soil microbial toxicity and phytotoxicity in the soil ecosystem. The effects of CuO and ZnO nanoparticles (NPs) and microparticles (MPs) on soil microbial toxicity, phytotoxicity, and bioaccumulation in two crops (Cucumis sativus and Zea mays) were estimated in a soil microcosm. In the microcosm system, soil was artificially contaminated with 1,000 mg/kg CuO and ZnO NPs and MPs. After 15 days, we compared the microbial toxicity and phytotoxicity by particle size. In addition, C. sativus and Z. mays were cultivated in soils treated with CuO NPs and ZnO NPs, after which the treatment effects on bioaccumulation were evaluated. NPs were more toxic than MPs to microbes and plants in the soil ecosystem. We found that the soil enzyme activity and plant biomass were inhibited to the greatest extent by CuO NPs. However, in a Biolog test, substrate utilization patterns were more dependent upon metal type than particle size. Another finding indicated that the metal NP uptake amounts of plants depend on the plant species. In the comparison between C. sativus and Z. mays, the accumulation of Cu and Zn by C. sativus was noticeably higher. These findings show that metal oxide NPs may negatively impact soil bacteria and plants. In addition, the accumulation patterns of NPs depend on the plant species. PMID:23751560

  14. Metal Toxicity Affects Fungal and Bacterial Activities in Soil Differently

    Microsoft Academic Search

    R. M. C. P. Rajapaksha; M. A Tobor-Kaplon; E. Baath

    2004-01-01

    Although the toxic effect of heavy metals on soil microorganism activity is well known, little is known about the effects on different organism groups. The influence of heavy metal addition on total, bacterial, and fungal activities was therefore studied for up to 60 days in a laboratory experiment using forest soil contaminated with different concentrations of Zn or Cu. The

  15. The Production of Active Nitrogen in the Soil

    E-print Network

    Fraps, G. S. (George Stronach)

    1908-01-01

    :AS AGRICULTURAL EXPERIMENT STAT1 'ON. BULLETIN NO. 106 JULY, 1908 oduction of Active Nitrogen in the Soil. By G. S. FRAPS, Ph. D., Chemist. Post Office COLLEGE STATION, BRAZOS COUNTY, TEX-,. CULTUF IAL EXF 'ERIMENT STATIONS. OFFICERS... of Introduction .......................................................... 4 Methods of Work ..................................................... 5 ............... I Nature of Soil on Production of Active Nitrogen 6...

  16. Concentration-dependent effect of photoluminescent carbon dots on the microbial activity of the soil studied by combination methods.

    PubMed

    Liu, Wenjuan; Yao, Jun; Chai, Hankuai; Zhao, Zhibo; Zhang, Chi; Jin, Jingnan; Choi, Martin M F

    2015-03-01

    Carbon dots (Cdots) have a great potential for their widespread biological applications. However, there are a few studies on the biosafety of Cdots. In this work, the biological effect of Cdots on soil microorganism was analyzed by microcalorimetry, soil enzymatic activities, and denaturing gradient gel electrophoresis (DGGE). The addition of Cdots causes a gradual increase of the maximum heat power (P peak) and the growth rate (k) at low concentration of Cdots (0.0-50.00 ?g/g). But there is no significant effect of Cdots on the total heat output (Q total). The urease and fluorescein diacetate esterase activities demonstrate that introduction of Cdots to soil has almost no impact on the structure and function of the soil microbial community and microbial processes. The DGGE results exhibit that the control and the Cdots-treated soils display similar patterns, indicating that Cdots have little effect on the microbial community structure. PMID:25769105

  17. Effects of Fertilization on Tomato Growth and Soil Enzyme Activity

    NASA Astrophysics Data System (ADS)

    Mu, Zhen; Hu, Xue-Feng; Cheng, Chang; Luo, Zhi-qing

    2015-04-01

    To study the effects of different fertilizer applications on soil enzyme activity, tomato plant growth and tomato yield and quality, a field experiment on tomato cultivation was carried out in the suburb of Shanghai. Three fertilizer treatments, chemical fertilizer (CF) (N, 260 g/kg; P, 25.71g/kg; K, 83.00g/kg), rapeseed cake manure (CM) (N, 37.4 g/kg; P, 9.0 g/kg; K, 8.46 g/kg), crop-leaf fermenting manure (FM) (N, 23.67 g/kg; P, 6.39 g/kg; K 44.32 g/kg), and a control without using any fertilizers (CK), were designed. The total amounts of fertilizer application to each plot for the CF, CM, FM and CK were 0.6 kg, 1.35 kg, 3.75 kg and 0 kg, respectively, 50% of which were applied as base fertilizer, and another 50% were applied after the first fruit picking as top dressing. Each experimental plot was 9 m2 (1 m × 9 m) in area. Each treatment was replicated for three times. No any pesticides and herbicides were applied during the entire period of tomato growth to prevent their disturbance to soil microbial activities. Soil enzyme activities at each plot were constantly tested during the growing period; the tomato fruit quality was also constantly analyzed and the tomato yield was calculated after the final harvesting. The results were as follows: (1) Urease activity in the soils treated with the CF, CM and FM increased quickly after applying base fertilizer. That with the CF reached the highest level. Sucrase activity was inhibited by the CF and CM to some extent, which was 32.4% and 11.2% lower than that with the CK, respectively; while that with the FM was 15.7% higher than that with the CK. Likewise, catalase activity with the CF increased by 12.3% - 28.6%; that with the CM increased by 87.8% - 95.1%; that with the FM increased by 86.4% - 93.0%. Phosphatase activity with the CF increased rapidly and reached a maximum 44 days after base fertilizer application, and then declined quickly. In comparison, that with the CM and FM increased slowly and reached a maximum 66 days after base fertilizer application, but maintained the high level for a long time. In short, the application of organic manure, especially the fermenting manure, is more beneficial to maintain high levels of soil enzyme activities and biodiversity. (2) The tomato yield treated with the CF, CM, FM and CK was 50055 kg/ha, 37814 kg/ha, 36965 kg/ha and 29937 kg/ha, respectively. The yield increasing rates of the CF, CM and FM were 67.2%, 26.3% and 23.5%, respectively. The application of chemical fertilizer could raise the tomato yield more effectively. The use of organic manure, especially the fermenting manure, however, could improve the fruit quality more effectively, especially increase soluble sugar and vitamin C contents and reduce nitrate content in tomato fruit significantly. The application of biological fermenting manure is beneficial to promote the recycling agriculture in China. It could also be used in the organic farming promisingly.

  18. Impact of Long-Term Forest Enrichment Planting on the Biological Status of Soil in a Deforested Dipterocarp Forest in Perak, Malaysia

    PubMed Central

    Karam, D. S.; Arifin, A.; Radziah, O.; Shamshuddin, J.; Majid, N. M.; Hazandy, A. H.; Zahari, I.; Nor Halizah, A. H.; Rui, T. X.

    2012-01-01

    Deforestation leads to the deterioration of soil fertility which occurs rapidly under tropical climates. Forest rehabilitation is one of the approaches to restore soil fertility and increase the productivity of degraded areas. The objective of this study was to evaluate and compare soil biological properties under enrichment planting and secondary forests at Tapah Hill Forest Reserve, Perak after 42 years of planting. Both areas were excessively logged in the 1950s and left idle without any appropriate forest management until 1968 when rehabilitation program was initiated. Six subplots (20?m × 20?m) were established within each enrichment planting (F1) and secondary forest (F2) plots, after which soil was sampled at depths of 0–15?cm (topsoil) and 15–30?cm (subsoil). Results showed that total mean microbial enzymatic activity, as well as biomass C and N content, was significantly higher in F1 compared to F2. The results, despite sample variability, suggest that the rehabilitation program improves the soil biological activities where high rate of soil organic matter, organic C, N, suitable soil acidity range, and abundance of forest litter is believed to be the predisposing factor promoting higher population of microbial in F1 as compared to F2. In conclusion total microbial enzymatic activity, biomass C and biomass N evaluation were higher in enrichment planting plot compared to secondary forest. After 42 years of planting, rehabilitation or enrichment planting helps to restore the productivity of planted forest in terms of biological parameters. PMID:22606055

  19. Biological activities of Brucella abortus lipopolysaccharides.

    PubMed Central

    Moreno, E; Berman, D T; Boettcher, L A

    1981-01-01

    Purified lipopolysaccharide (LPS) from smooth (s) and rough (R) strains of Brucella abortus and lipid A isolated from S-LPS by mild acid hydrolysis were examined in several assays of biological activity. Brucella S- and R-LPSs and Brucella lipid A activated the complement cascade. Previously reported mitogenic activation by Brucella LPSs of spleen cells from endotoxin-resistant C3H/HeJ mice was confirmed and also produced by isolated Brucella lipid A. Mitogenicity was not inhibited by polymyxin B, and amino acid analysis showed no binding of polymyxin B to Brucella LPS under conditions in which mitogenicity of phenol-water-extracted Escherichia coli LPS was inhibited. S and R Brucella LPSs and lipid A all produced equivalent polyclonal stimulation of C3H/HeJ and C3H/HeAU spleen cells. Crude and purified LPS from S but not from R B. abortus was toxic for outbred mice, with 50% lethal doses approximately six times greater than that for E. coli LPS. S- and R-LPSs were abortifacient in pregnant outbred mice. S Brucella LPS was lethal for carrageenen-pretreated C3H/HeJ and C3H/HeAU mice, whereas only C3H/HeAU mice were killed by E. coli LPS. The data are consistent with the hypothesis that the unique fatty acid composition of Brucella lipid A is responsible for its biological activity in endotoxin-resistant C3H/HeJ mice. The participation of the protein strongly bound to the lipid A cannot be excluded, but its mode of action, if any, is different from that of the lipid A-associated protein of enterobacterial LPS. PMID:6783538

  20. Efficiency of soil organic and inorganic amendments on the remediation of a contaminated mine soil: II. Biological and ecotoxicological evaluation.

    PubMed

    Pardo, T; Clemente, R; Alvarenga, P; Bernal, M P

    2014-07-01

    The feasibility of two organic materials (pig slurry and compost) in combination with hydrated lime for the remediation of a highly acidic trace elements (TEs) contaminated mine soil was assessed in a mesocosm experiment. The effects of the amendments on soil biochemical and ecotoxicological properties were evaluated and related with the main physicochemical characteristics of soil and soil solution. The original soil showed impaired basic ecological functions due to the high availability of TEs, its acidic pH and high salinity. The three amendments slightly reduced the direct and indirect soil toxicity to plants, invertebrates and microorganisms as a consequence of the TEs' mobility decrease in topsoil, reducing therefore the soil associated risks. The organic amendments, especially compost, thanks to the supply of essential nutrients, were able to improve soil health, as they stimulated plant growth and significantly increased enzyme activities related with the key nutrients in soil. Therefore, the use of compost or pig slurry, in combination with hydrated lime, decreased soil ecotoxicity and seems to be a suitable management strategy for the remediation of highly acidic TEs contaminated soils. PMID:24875876

  1. Microbial Community Structure and Enzyme Activities in Semiarid Agricultural Soils

    NASA Astrophysics Data System (ADS)

    Acosta-Martinez, V. A.; Zobeck, T. M.; Gill, T. E.; Kennedy, A. C.

    2002-12-01

    The effect of agricultural management practices on the microbial community structure and enzyme activities of semiarid soils of different textures in the Southern High Plains of Texas were investigated. The soils (sandy clay loam, fine sandy loam and loam) were under continuous cotton (Gossypium hirsutum L.) or in rotations with peanut (Arachis hypogaea L.), sorghum (Sorghum bicolor L.) or wheat (Triticum aestivum L.), and had different water management (irrigated or dryland) and tillage (conservation or conventional). Microbial community structure was investigated using fatty acid methyl ester (FAME) analysis by gas chromatography and enzyme activities, involved in C, N, P and S cycling of soils, were measured (mg product released per kg soil per h). The activities of b-glucosidase, b-glucosaminidase, alkaline phosphatase, and arylsulfatase were significantly (P<0.05) increased in soils under cotton rotated with sorghum or wheat, and due to conservation tillage in comparison to continuous cotton under conventional tillage. Principal component analysis showed FAME profiles of these soils separated distinctly along PC1 (20 %) and PC2 (13 %) due to their differences in soil texture and management. No significant differences were detected in FAME profiles due to management practices for the same soils in this sampling period. Enzyme activities provide early indications of the benefits in microbial populations and activities and soil organic matter under crop rotations and conservation tillage in comparison to the typical practices in semiarid regions of continuous cotton and conventional tillage.

  2. Soil Physicochemical and Biological Properties of Paddy-Upland Rotation: A Review

    PubMed Central

    Lv, Teng-Fei; Chen, Yong; Westby, Anthony P.; Ren, Wan-Jun

    2014-01-01

    Paddy-upland rotation is an unavoidable cropping system for Asia to meet the increasing demand for food. The reduction in grain yields has increased the research interest on the soil properties of rice-based cropping systems. Paddy-upland rotation fields are unique from other wetland or upland soils, because they are associated with frequent cycling between wetting and drying under anaerobic and aerobic conditions; such rotations affect the soil C and N cycles, make the chemical speciation and biological effectiveness of soil nutrient elements varied with seasons, increase the diversity of soil organisms, and make the soil physical properties more difficult to analyze. Consequently, maintaining or improving soil quality at a desirable level has become a complicated issue. Therefore, fully understanding the soil characteristics of paddy-upland rotation is necessary for the sustainable development of the system. In this paper, we offer helpful insight into the effect of rice-upland combinations on the soil chemical, physical, and biological properties, which could provide guidance for reasonable cultivation management measures and contribute to the improvement of soil quality and crop yield. PMID:24995366

  3. Soil surface disturbances in cold deserts: Effects on nitrogenase activity in cyanobacterial-lichen soil crusts

    USGS Publications Warehouse

    Belnap, Jayne

    1996-01-01

    CyanobacteriaMichen soil crusts can be a dominant source of nitrogen for cold-desert ecosystems. Effects of surface disturbance from footprints, bike and vehicle tracks on the nitrogenase activity in these crusts was investigated. Surface disturbances reduced nitrogenase activity by 30-100%. Crusts dominated by the cyanobacterium Microcoleus vaginatus on sandy soils were the most susceptible to disruption; crusts on gypsiferous soils were the least susceptible. Crusts where the soil lichen Collema tenax was present showed less immediate effects; however, nitrogenase activity still declined over time. Levels of nitrogenase activity reduction were affected by the degree of soil disruption and whether sites were dominated by cyanobacteria with or without heterocysts. Consequently, anthropogenic surface disturbances may have serious implications for nitrogen budgets in these ecosystems.

  4. Effects of Zero Tillage (No-Till) Conservation Agriculture on soil physical and biological properties and their contributions to sustainability

    NASA Astrophysics Data System (ADS)

    Landers, John N.; Rass, Gerard; de Freitas, Pedro L.; Basch, Gottlieb; González Sanchez, Emilio J.; Tabaglio, Vincenzo; Kassan, Amir; Derpsch, Rolf; Friedrich, Theodor; Giupponi, Luca

    2013-04-01

    Not cultivating soil, rotating crops over the years, and leaving crop residues on the surface in the practice of zero tillage/conservation agriculture (ZT/CA) reverses the historically accelerating degradation of soil organic matter (SOM) and soil structure, while increasing soil biological activity by a factor of 2 to 4. The results of this are many: (a) not cultivating reduces soil compaction, leaving old root holes to facilitate internal drainage, averts the pulverization of soil aggregates and formation of pans, reduces draft power for planting and gives shelter, winter food and nesting sites for fauna, (b) crop residues on the surface practically eliminate wind and water erosion, reduce soil moisture loss through the mulch effect, slow spring warm-up (possibly offset by a lower specific heat demand with less water retention in surface soil) and act as a reserve of organically-compounded nutrients (as they decompose to humus), (c) more SOM means higher available water and nutrient retention, higher biological activity year round (enhancing biological controls), higher levels of water-stable aggregates and a positive carbon sink in incremental SOM. The positive impacts for society are: (i) more and cheaper food, (ii) reduced flood and drought-induced famine risks, (iii) a positive carbon sink in SOM and possible reductions in NO2 emissions, (iv) cleaner water and greater aquifer recharge due to reduced runoff, (v) cleaner air through effective elimination of dust as a product of cultivation (vi) less water pollution and greater aquifer recharge from reduced rainfall runoff, (vii) farm diesel consumption halved, (viii) reduced demand for (tropical) de-forestation, by permitting crop expansion on steeper lands, (ix) increased wildlife populations (skylarks, plovers, partridge and peccaries) and (x) an improved conservation mindset in farmers. It is notable that, in spite of successful practitioners in all European countries, mainstream adoption is still to come: Europés ZT/CA area is 1.35 million hectares, while the world area is now some 125 million and growing at a rate of 7 million hectares per year. More scientific measurements of the benefits of this system are required, both to assist adoption and to trigger policy measures. In the EEC, CAP reform (greening) needs to consider making environmental services payments for these social benefits since a reduction in single farm payments is ineluctable and carbon footprint reduction is of the essence, in the face of constantly-rising fuel prices and the need to cut GHG emissions. Therefore, as the principal farm tool which offers an effective and immediate solution towards positive changes in soil quality, productivity and sustainability, ZT/CA adoption needs financial incentives, which have high economic and environmental returns to society.

  5. Natural physical and biological processes compromise the long-term performance of compacted soil caps

    SciTech Connect

    Smith, E.D.

    1995-12-01

    Compacted soil barriers are components of essentially all caps placed on closed waste disposal sites. The intended functions of soil barriers in waste facility caps include restricting infiltration of water and release of gases and vapors, either independently or in combination with synthetic membrane barriers, and protecting other manmade or natural barrier components. Review of the performance of installed soil barriers and of natural processes affecting their performance indicates that compacted soil caps may function effectively for relatively short periods (years to decades), but natural physical and biological processes can be expected to cause them to fail in the long term (decades to centuries). This paper addresses natural physical and biological processes that compromise the performance of compacted soil caps and suggests measures that may reduce the adverse consequences of these natural failure mechanisms.

  6. Winter biotic activity and production of CO2 in Siberian soils: A factor in the greenhouse effect

    Microsoft Academic Search

    S. A. Zimov; G. M. Zimova; S. P. Daviodov; A. I. Daviodova; Y. V. Voropaev; Z. V. Voropaeva; S. F. Prosiannikov; O. V. Prosiannikova; I. V. Semiletova; I. P. Semiletov

    1993-01-01

    Soil CO2 emissions at latitudes near 70°N in northeastern Siberia have been measured and occur at levels high enough to account for the observed winter maximum in atmospheric CO2 concentrations in this latitude. This CO2 is produced by biological activity at the bottom of the active layer above the permafrost. Ecological and anthropological factors may play a role in stimulating

  7. Soil Biological Parameters Influenced By Cocoa Management Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cropping systems have a profound influence on the soil micro-fauna and they are responsible for nutrient cycling, and add stability to the soil. At Tarapoto, Peru, two field experiments were established on acidic medium fertility Alfisol to assess the influence of management systems on cacao rhizosp...

  8. Soil Biology & Biochemistry 38 (2006) 29672970 Short communication

    E-print Network

    Rilli, Matthias C.

    2006-01-01

    of arbuscular mycorrhizal fungi to DOC leaching in grassland through losses of glomalin-related soil protein March 2006 Available online 11 May 2006 Abstract Arbuscular mycorrhizal fungi (AMF) have multiple. Keywords: Dissolved organic carbon; Grassland; Carbon cycling; Soil fungi; Leachate Arbuscular mycorrhizal

  9. Soil Biological Engineering to Enhance your Bottom Line

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the importance of soil to all life on Earth, soil is the not-well-understood ‘big black box’. Therefore, the next revolution in agriculture needs not to be a green revolution or an iron (i.e. equipment) revolution; it needs to be a brown revolution. In this brown revolution, the root of th...

  10. Soil enzyme activities and organic matter composition in a turfgrass chronosequence

    Microsoft Academic Search

    Wei Shi; Emily Dell; Daniel Bowman; Kannan Iyyemperumal

    2006-01-01

    Highly managed turfgrass systems accumulate considerable soil organic C, which supports a diverse and robust soil microbial community. Degradation of this soil organic C is mediated by a suite of soil enzymes. The relationship between these enzyme activities and the quality of soil organic C is central to understanding the dynamics of soil organic matter. We examined the activities of

  11. Biological activities of Synanceja horrida (stonefish) venom.

    PubMed

    Khoo, H E; Yuen, R; Poh, C H; Tan, C H

    1992-01-01

    Some biological and neurochemical properties of the venom of stonefish (Syanceja horrida) were investigated. The venom exhibited oedema-inducing, haemolytic, hyaluronidase, thrombin-like, alkaline phosphomonoesterase, 5' nucleotidase, acetylcholinesterase, phosphodiesterase, arginine esterase, and arginine amidase activities. Recalcification clotting time, prothrombin, and kaolin-cephalin clotting times were increased 1.7-2.3- and 2.4-fold respectively. The LD50 (i.v. mouse) was 300 micrograms/Kg. Its effects on uptake and stimulation of neurotransmitter synthesis and release were observed in rat brain synaptosomes. In the presence of 100 micrograms venom, uptake of [methyl-3H] choline in rat brain synaptosomes was inhibited 70%, while that of 4-amino-n-[U-14C] butyric acid was inhibited 20%. The toxin also stimulated the release of [3H]-acetylcholine from the synaptosomes. PMID:1364268

  12. Biologically Active and Antimicrobial Peptides from Plants

    PubMed Central

    Salas, Carlos E.; Badillo-Corona, Jesus A.; Ramírez-Sotelo, Guadalupe; Oliver-Salvador, Carmen

    2015-01-01

    Bioactive peptides are part of an innate response elicited by most living forms. In plants, they are produced ubiquitously in roots, seeds, flowers, stems, and leaves, highlighting their physiological importance. While most of the bioactive peptides produced in plants possess microbicide properties, there is evidence that they are also involved in cellular signaling. Structurally, there is an overall similarity when comparing them with those derived from animal or insect sources. The biological action of bioactive peptides initiates with the binding to the target membrane followed in most cases by membrane permeabilization and rupture. Here we present an overview of what is currently known about bioactive peptides from plants, focusing on their antimicrobial activity and their role in the plant signaling network and offering perspectives on their potential application. PMID:25815307

  13. Stoichiometry of soil enzyme activity at global scale

    Microsoft Academic Search

    Robert L. Sinsabaugh; Christian L. Lauber; Michael N. Weintraub; Bony Ahmed; Steven D. Allison; Chelsea Crenshaw; Alexandra R. Contosta; Daniela Cusack; Serita Frey; Marcy E. Gallo; Tracy B. Gartner; Sarah E. Hobbie; Keri Holland; Bonnie L. Keeler; Jennifer S. Powers; Martina Stursova; Cristina Takacs-Vesbach; Mark P. Waldrop; Matthew D. Wallenstein; Donald R. Zak; Lydia H. Zeglin

    2008-01-01

    Extracellular enzymes are the proximate agents of organic matter decomposition and measures of these activities can be used as indicators of microbial nutrient demand. We conducted a global-scale meta-analysis of the seven-most widely measured soil enzyme activities, using data from 40 ecosystems. The activities of b-1,4-glucosidase, cellobiohydrolase, b-1,4-N-acetylglucosaminidase and phosphatase g )1 soil increased with organic matter concentration; leucine aminopeptidase,

  14. Biological activity of mammalian transcriptional repressors.

    PubMed

    Thiel, G; Lietz, M; Bach, K; Guethlein, L; Cibelli, G

    2001-06-01

    Research on the regulation of transcription in mammals has focused in recent years mainly on the mechanism of transcriptional activation. However, transcriptional repression mediated by repressor proteins is a common regulatory mechanism in mammals and might play an important role in many biological processes. To understand the molecular mechanism of transcriptional repression, the activity of eight mammalian repressors or repressor domains was investigated using a set of model promoters in combination with two different transcriptional detection methods. The repressors studied were: REST, the thyroid hormone receptors alpha and beta, the zinc finger protein NK10 containing a 'krüppel-associated box' (KRAB), repressor domains derived from the proteins Egr-1, Oct2A and Dr1 and the repressor/activator protein YY1. Here we show that the repressor domains of REST, Egr-1, the thyroid hormone receptors alpha< and beta and NK10 were transferable to a heterologous DNA-binding domain and repressed transcription from proximal and distal positions. Moreover, these repressor domains also blocked the activity of a strong viral enhancer in a 'remote position'. Thus, these domains are 'general' transcriptional repressor domains. The 'krüppel-associated box' was the most powerful repressor domain tested. In contrast, the repressor domains derived from Oct2A and Dr1 were inactive when fused to a heterologous DNA-binding domain. The repressor domain of YY1 exhibited transcriptional repression activity only in one of the transcriptional assay systems. The recruitment of histone deacetylases to the proximity of the basal transcriptional apparatus was recently discussed as a mechanism for some mammalian transcriptional repressor proteins. Here we show here that histone deacetylase 2, targeted to the reporter gene via DNA-protein interaction, functions as a transcriptional repressor protein regardless of the location of its binding site within the transcription unit. PMID:11501753

  15. Biogeosystem technique as a method to overcome the Biological and Environmental Hazards of modern Agricultural, Irrigational and Technological Activities

    NASA Astrophysics Data System (ADS)

    Kalinitchenko, Valery; Batukaev, Abdulmalik; Zinchenko, Vladimir; Zarmaev, Ali; Magomadov, Ali; Chernenko, Vladimir; Startsev, Viktor; Bakoev, Serojdin; Dikaev, Zaurbek

    2014-05-01

    Modern challenge for humanity is to replace the paradigm of nature use and overcome environmental hazards of agronomy, irrigation, industry, and other human activities in biosphere. It is utterly reasonable to stop dividing biosphere on shares - the human habitat and the environment. In the 21st century it is an outdated anthropocentrism. Contradicting himself to biosphere Humankind has the problems. The new paradigm of biosphere control by methods of Biogeosystem technique is on agenda of Humankind. Key directions of Biogeosystem technique. Tillage. Single rotary milling 20…30-50…60 sm soil layer optimizes the evolution and environment of soil, creates a favorable conditions for the rhizosphere, increases the biological productivity of biosphere by 30-50% compared to the standard agricultural practices for the period up to 40 years. Recycle material. Recycling of mineral and organic substances in soil layer of 20…30-50…60 sm in rotary milling soil processing provides wastes clean return to biosphere. Direct intrasoil substances synthesis. Environmentally friendly robot wasteless nanotechnology provides direct substances synthesis, including fertilizers, inside the soil. It eliminates the prerequisites of the wastes formation under standard industrial technologies. Selective substance's extraction from soil. Electrochemical robotic nanotechnology provides selective substances extraction from soil. The technology provides recovery, collection and subsequent safe industrial use of extracted substances out of landscape. Saving fresh water. An important task is to save fresh water in biosphere. Irrigation spends water 4-5 times more of biological requirements of plants, leads to degradation of soil and landscape. The intrasoil pulse continuous-discrete paradigm of irrigation is proposed. It provides the soil and landscape conservation, increases the biological productivity, save the fresh water up to 10-20 times. The subsurface soil rotary processing and intrasoil pulsed continuous-discrete irrigation provide environmentally safe disposal of municipal, industrial, biological and agricultural wastes. Hazardous chemical and biological agents are under the soil surface. It provided a medical and veterinary safety of environment. Biogeosystem technic controls the equilibria in the soil and soil solution, prevents excessive mineralization of organic matter in the surface layers of soil. Simultaneously a soil chemical reduction excluded, biological substance do not degrade to gases. Products of organic matter decomposition are directed to the food chain, 100% waste recycling is obtained. Biogeosystems technique allows producing more biological products hence to recycle excessive amount of man-made CO2 and other substances. Biogeosystems technique increases the rate of photosynthesis of the biosphere, the degree of air ionization. This enhances the formation of rains over land, ensures stability of the ionosphere, magnetosphere and atmosphere of Earth. The nowadays technologies allow applying technical solutions based on Biogeosystem technique, there is unique opportunity to accelerate the noosphere new technological platform.

  16. Suppression of annual Bromus tectorum by perennial Agropyron cristatum: roles of soil nitrogen availability and biological soil space

    PubMed Central

    Blank, Robert R.; Morgan, Tye; Allen, Fay

    2015-01-01

    Worldwide, exotic invasive grasses have caused numerous ecosystem perturbations. Rangelands of the western USA have experienced increases in the size and frequency of wildfires largely due to invasion by the annual grass Bromus tectorum. Rehabilitation of invaded rangelands is difficult; but long-term success is predicated on establishing healthy and dense perennial grass communities, which suppress B. tectorum. This paper reports on two experiments to increase our understanding of soil factors involved in suppression. Water was not limiting in this study. Growth of B. tectorum in soil conditioned by and competing with the exotic perennial Agropyron cristatum was far less relative to its growth without competition. When competing with A. cristatum, replacing a portion of conditioned soil with fresh soil before sowing of B. tectorum did not significantly increase its growth. The ability of conditioned soil to suppress B. tectorum was lost when it was separated from growing A. cristatum. Soil that suppressed B. tectorum growth was characterized by low mineral nitrogen (N) availability and a high molar ratio of NO2? in the solution-phase pool of NO2?+NO3?. Moreover, resin availability of NO2?+NO3? explained 66 % of the variability in B. tectorum above-ground mass, attesting to the importance of A. cristatum growth in reducing N availability to B. tectorum. Trials in which B. tectorum was suppressed the most were characterized by very high shoot/root mass ratios and roots that have less root hair growth relative to non-suppressed counterparts, suggesting co-opting of biological soil space by the perennial grass as another suppressive mechanism. Greater understanding of the role of biological soil space could be used to breed and select plant materials with traits that are more suppressive to invasive annual grasses. PMID:25603967

  17. Suppression of annual Bromus tectorum by perennial Agropyron cristatum: roles of soil nitrogen availability and biological soil space.

    PubMed

    Blank, Robert R; Morgan, Tye; Allen, Fay

    2015-01-01

    Worldwide, exotic invasive grasses have caused numerous ecosystem perturbations. Rangelands of the western USA have experienced increases in the size and frequency of wildfires largely due to invasion by the annual grass Bromus tectorum. Rehabilitation of invaded rangelands is difficult; but long-term success is predicated on establishing healthy and dense perennial grass communities, which suppress B. tectorum. This paper reports on two experiments to increase our understanding of soil factors involved in suppression. Water was not limiting in this study. Growth of B. tectorum in soil conditioned by and competing with the exotic perennial Agropyron cristatum was far less relative to its growth without competition. When competing with A. cristatum, replacing a portion of conditioned soil with fresh soil before sowing of B. tectorum did not significantly increase its growth. The ability of conditioned soil to suppress B. tectorum was lost when it was separated from growing A. cristatum. Soil that suppressed B. tectorum growth was characterized by low mineral nitrogen (N) availability and a high molar ratio of [Formula: see text] in the solution-phase pool of [Formula: see text] Moreover, resin availability of [Formula: see text] explained 66 % of the variability in B. tectorum above-ground mass, attesting to the importance of A. cristatum growth in reducing N availability to B. tectorum. Trials in which B. tectorum was suppressed the most were characterized by very high shoot/root mass ratios and roots that have less root hair growth relative to non-suppressed counterparts, suggesting co-opting of biological soil space by the perennial grass as another suppressive mechanism. Greater understanding of the role of biological soil space could be used to breed and select plant materials with traits that are more suppressive to invasive annual grasses. PMID:25603967

  18. Arid soil microbial enzymatic activity profile as affected by geographical location and soil degradation status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evaluating soil health is critical for any successful remediation effort. Arid lands, with their minimal carbon and water contents, low nutritional status and restricted, seasonal microbial activity pose specific challenges to soil health restoration and by extension, restoration of ecosystem repr...

  19. Evaluation of the Soil Moisture Active Passive Mission (SMAP) merged radar-radiometer soil moisture algorithm

    Microsoft Academic Search

    N. Das; D. Entekhabi; E. G. Njoku

    2010-01-01

    The Soil Moisture Active Passive (SMAP) mission is recommended by the U.S. National Research Council Committee on Earth Science and Applications from Space. The SMAP mission is under development with a target launch date in late 2014. The SMAP mission will provide high resolution (~9 km) soil moisture product at a global extent. The SMAP instrument architecture incorporates an L-band

  20. Soil Moisture Active Passive Validation Experiment 2008 (SMAPVEX08)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Soil Moisture Active Passive Mission (SMAP) is currently addressing issues related to the development and selection of soil moisture retrieval algorithms. Several forums have identified a number of specific questions that require supporting field experiments. Addressing these issues as soon as p...

  1. Measurements of microbial community activities in individual soil macroaggregates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The functional potential of single soil aggregates may provide insights into the localized distribution of microbial activities better than traditional assays conducted on bulk quantities of soil. Thus, we scaled down enzyme assays for ß-glucosidase, N-acetyl-ß-D-glucosaminidase, lipase, and leucine...

  2. MICROBIAL COMMUNITY STRUCTURE AND ENZYME ACTIVITIES IN SEMIARID AGRICULTURAL SOILS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of agricultural management practices on the microbial community structure and enzyme activities of semiarid soils of different textures in the Southern High Plains of Texas were investigated. The soils (sandy clay loam, fine sandy loam and loam) were under continuous cotton (Gossypium hir...

  3. ACID RAIN AND SOIL MICROBIAL ACTIVITY: EFFECTS AND THEIR MECHANISMS

    EPA Science Inventory

    In the investigation, our aim was to determine if acid rain affects soil microbial activity and to identify possible mechanisms of observed effects. A Sierran forest soil (pH 6.4) planted with Ponderosa pine seedlings was exposed to simulated rain (pH 2.0, 3.0, 4.0 and 5.6) with ...

  4. Diversity and Activity of Methanotrophic Bacteria in Different Upland Soils

    Microsoft Academic Search

    Claudia Knief; A. Lipski; P. F. Dunfield

    2003-01-01

    Samples from diverse upland soils that oxidize atmospheric methane were characterized with regard to methane oxidation activity and the community composition of methanotrophic bacteria (MB). MB were identified on the basis of the detection and comparative sequence analysis of the pmoA gene, which encodes a subunit of particulate methane monooxygenase. MB commonly detected in soils were closely related to Methylocaldum

  5. Smart Sensing Strategies: Insights from a Biological Active Sensing System

    E-print Network

    Nelson, Mark E.

    Smart Sensing Strategies: Insights from a Biological Active Sensing System Mark E. Nelson-Champaign, Urbana, IL 61801, USA m-nelson@illinois.edu ABSTRACT Biological sensory systems efficiently and reliably and goals. Understanding the sensory mechanisms and information processing principles that biological

  6. Effect of elevated CO2 on degradation of azoxystrobin and soil microbial activity in rice soil.

    PubMed

    Manna, Suman; Singh, Neera; Singh, V P

    2013-04-01

    An experiment was conducted in open-top chambers (OTC) to study the effect of elevated CO2 (580?±?20 ?mol mol(-1)) on azoxystrobin degradation and soil microbial activities. Results indicated that elevated CO2 did not have any significant effect on the persistence of azoxystrobin in rice-planted soil. The half-life values for the azoxystrobin in rice soils were 20.3 days in control (rice grown at ambient CO2 outdoors), 19.3 days in rice grown under ambient CO2 atmosphere in OTC, and 17.5 days in rice grown under elevated CO2 atmosphere in OTC. Azoxystrobin acid was recovered as the only metabolite of azoxystrobin, but it did not accumulate in the soil/water and was further metabolized. Elevated CO2 enhanced soil microbial biomass (MBC) and alkaline phosphatase activity of soil. Compared with rice grown at ambient CO2 (both outdoors and in OTC), the soil MBC at elevated CO2 increased by twofold. Elevated CO2 did not affect dehydrogenase, fluorescein diacetate, and acid phosphatase activity. Azoxystrobin application to soils, both ambient and elevated CO2, inhibited alkaline phosphates activity, while no effect was observed on other enzymes. Slight increase (1.8-2 °C) in temperature inside OTC did not affect microbial parameters, as similar activities were recorded in rice grown outdoors and in OTC at ambient CO2. Higher MBC in soil at elevated CO2 could be attributed to increased carbon availability in the rhizosphere via plant metabolism and root secretion; however, it did not significantly increase azoxystrobin degradation, suggesting that pesticide degradation was not the result of soil MBC alone. Study suggested that increased CO2 levels following global warming might not adversely affect azoxystrobin degradation. However, global warming is a continuous and cumulative process, therefore, long-term studies are necessary to get more realistic assessment of global warming on fate of pesticide. PMID:22773147

  7. Changes in the cellulolytic activity of urban soils induced by the removal of plant litter (using Moscow as an example)

    NASA Astrophysics Data System (ADS)

    Ivanova, A. E.; Nikolaeva, V. V.; Marfenina, O. E.

    2015-05-01

    The parameters of the biological activity in the upper horizons of an urban soil in Tushino (the northwestern administrative district of Moscow) without the litter horizon because of the regular removal of the plant litter and an undisturbed background Albic Retisol with the litter horizon were compared. In the studied soils, the levels and dynamics of the cellulolytic activity were comparable and generally increased from the spring to the fall seasons. This increase was more pronounced in the urban soil during the leaf fall. The seasonal dynamic of the CO2 emission in the urban soil (upon its moistening) was similar to that in the background soil, though the absolute values were significantly lower in the summer and fall seasons. The method of substrate-induced respiration (SIR) showed that the rise in the CO2 emission in response to the addition of cellulose in the urban soil was 1.5-2.0 times lower than that in the background soil. The increase in the cellulolytic activity upon the application of lime leaves ( Tilia cordata Mill.) in the uppermost 5 mm of the urban soil (immediately under the leaves) was also less pronounced than that in the natural background soil. At the same time, the increase in the CO2 emission upon the addition of cellulose into this layer was more pronounced and continued for a longer time in the urban soil.

  8. Biological soil crusts from arctic environments: characterization of the prokaryotic community and exopolysaccharidic matrix analysis.

    NASA Astrophysics Data System (ADS)

    Mugnai, Gianmarco; Ventura, Stefano; Mascalchi, Cristina; Rossi, Federico; Adessi, Alessandra; De Philippis, Roberto

    2015-04-01

    Biological soil crusts (BSCs) are highly specialized topsoil microbial communities widespread in many ecosystems, from deserts to polar regions. BSCs play an active role in promoting soil fertility and plant growth. In Arctic environments BSCs are involved in promoting primary succession after deglaciation, increasing moisture availability and nutrient immission at the topsoil. The organisms residing on BSCs produce extracellular polymeric substances (EPS) in response to the environmental characteristics, thus contributing to the increase of constraint tolerance. The aim of this study was to investigate the taxonomic diversity of microbial communities, together with the analysis of the chemical features of EPS, from BSC samples collected in several sites near Ny-?lesund, Norway. The phylogenetic composition of the prokaryotic community was assessed through a metagenomic approach. Exopolysaccharidic fractions were quantified using ion-exchange chromatography to determine the monosaccharidic composition. Size exclusion chromatography was used to determine the distribution of the EPS fractions. Abundance of phototrophic microorganisms, which are known to contribute to EPS excretion, was also evaluated. Results underlined the complexity of the microbial communities, showing a high level of diversity within the BSC sampled analyzed. The analysis of the polysaccharide composition displayed a high number of constituent sugars; the matrix was found to be constituted by two main fractions, a higher molecular weight (2 10 exp(6) Da) and a lower molecular weight fraction (< 100 10 exp(3) Da). This study presents novel data concerning EPS of BSCs matrix in relationship with the microbial communities in cold environments.

  9. NASA's Soil Moisture Active Passive (SMAP) Observatory

    NASA Technical Reports Server (NTRS)

    Kellogg, Kent; Thurman, Sam; Edelstein, Wendy; Spencer, Michael; Chen, Gun-Shing; Underwood, Mark; Njoku, Eni; Goodman, Shawn; Jai, Benhan

    2013-01-01

    The SMAP mission will produce high-resolution and accurate global maps of soil moisture and its freeze/thaw state using data from a non-imaging synthetic aperture radar and a radiometer, both operating at L-band.

  10. Dynamics of soil organic carbon and microbial activity in treated wastewater irrigated agricultural soils along soil profiles

    NASA Astrophysics Data System (ADS)

    Jüschke, Elisabeth; Marschner, Bernd; Chen, Yona; Tarchitzky, Jorge

    2010-05-01

    Treated wastewater (TWW) is an important source for irrigation water in arid and semiarid regions and already serves as an important water source in Jordan, the Palestinian Territories and Israel. Reclaimed water still contains organic matter (OM) and various compounds that may effect microbial activity and soil quality (Feigin et al. 1991). Natural soil organic carbon (SOC) may be altered by interactions between these compounds and the soil microorganisms. This study evaluates the effects of TWW irrigation on the quality, dynamics and microbial transformations of natural SOC. Priming effects (PE) and SOC mineralization were determined to estimate the influence of TWW irrigation on SOC along soil profiles of agricultural soils in Israel and the Westbank. The used soil material derived from three different sampling sites allocated in Israel and The Palestinian Authority. Soil samples were taken always from TWW irrigated sites and control fields from 6 different depths (0-10, 10-20, 20-30, 30-50, 50-70, 70-100 cm). Soil carbon content and microbiological parameters (microbial biomass, microbial activities and enzyme activities) were investigated. In several sites, subsoils (50-160 cm) from TWW irrigated plots were depleted in soil organic matter with the largest differences occurring in sites with the longest TWW irrigation history. Laboratory incubation experiments with additions of 14C-labelled compounds to the soils showed that microbial activity in freshwater irrigated soils was much more stimulated by sugars or amino acids than in TWW irrigated soils. The lack of such "priming effects" (Hamer & Marschner 2005) in the TWW irrigated soils indicates that here the microorganisms are already operating at their optimal metabolic activity due to the continuous substrate inputs with soluble organic compounds from the TWW. The fact that PE are triggered continuously due to TWW irrigation may result in a decrease of SOC over long term irrigation. Already now this could be detected at some agricultural fields by SOC measurements (Jüschke 2009). Therefore attention has to be drawn especially on the carbon content and quality of the used TWW for irrigation purposes.

  11. SMOS Soil moisture Cal val activities

    NASA Astrophysics Data System (ADS)

    Kerr, Y.; Mialon, A.; Bitar, A. Al; Leroux, D.; Richaume, P.; Gruhier, C.; Berthon, L.; Novello, N.; Rudiger, C.; Bircher, S.; Wigneron, J. P.; Ferrazzoli, P.; Rahmoune, R.

    2012-04-01

    SMOS, successfully launched on November 2, 2009, uses an L Band radiometer with aperture synthesis to achieve a good spatial resolution.. It was developed and made under the leadership of the European Space Agency (ESA) as an Earth Explorer Opportunity mission. It is a joint program with the Centre National d'Etudes Spatiales (CNES) in France and the Centro para el Desarrollo Tecnologico Industrial (CDTI) in Spain. SMOS carries a single payload, an L band 2D interferometric,radiometer in the 1400-1427 MHz protected band. This wavelength penetrates well through the vegetation and with the atmosphere being almost transparent, it enables us to infer both soil moisture and vegetation water content. SMOS achieves an unprecedented spatial resolution of 50 km at L-band maximum (43 km on average) with multi angular-dual polarized (or fully polarized) brightness temperatures over the globe and with a revisit time smaller than 3 days. SMOS is now acquiring data and has undergone the commissioning phase. The data quality exceeds what was expected, showing very good sensitivity and stability. The data is however very much impaired by man made emission in the protected band, leading to degraded measurements in several areas including parts of Europe and China. Many different international teams are now performing cal val activities in various parts of the world, with notably large field campaigns either on the long time scale or over specific targets to address the specific issues. These campaigns take place in various parts of the world and in different environments, from the Antarctic plateau to the deserts, from rain forests to deep oceans. SMOS is a new sensor, making new measurements and paving the way for new applications. It requires a detailed analysis of the data so as to validate both the approach and the quality of the retrievals, and allow for monitoring and the evolution of the sensor. To achieve such goals it is very important to link efficiently ground measurement to satellite measurements through field campaigns and related airborne acquisitions. Comparison with models and other satellite products are necessary. It is in this framework that CESBIO has been involved with many groups to assess the data over many areas in close collaboration. This paper aims at summarising briefly the results (presented in detail in other presentations) to give a general overview and a general first taste of SMOS' performance, together with the identified gaps and next steps to be taken. This presentation could be the general introduction to Cal Val activities.

  12. Accommodating Students with Disabilities in Soil Science Activities

    NSDL National Science Digital Library

    S. Langley-Turnbaugh

    Soil science education is lacking in terms of accommodations for persons with disabilities to the extent that these individuals are often excluded from soil science activities in school, and from careers in the discipline. This article describes a study whose goal was to develop accommodations to the soils protocols currently being used in the GLOBE (Global Learning Observations to Benefit the Environment) program. These new materials are based on the principles of universal design in education (UDE), so that GLOBE activities and materials can be accessible to a broad range of students, including students with disabilities.

  13. Fate and activity of microorganisms introduced into soil.

    PubMed Central

    van Veen, J A; van Overbeek, L S; van Elsas, J D

    1997-01-01

    Introduced microorganisms are potentially powerful agents for manipulation of processes and/or components in soil. Fields of application include enhancement of crop growth, protection of crops against plant-pathogenic organisms, stimulation of biodegradation of xenobiotic compounds (bioaugmentation), and improvement of soil structure. Inoculation of soils has already been applied for decades, but it has often yielded inconsistent or disappointing results. This is caused mainly by a commonly observed rapid decline in inoculant population activity following introduction into soil, i.e., a decline of the numbers of inoculant cells and/or a decline of the (average) activity per cell. In this review, we discuss the available information on the effects of key factors that determine the fate and activity of microorganisms introduced into soil, with emphasis on bacteria. The factors addressed include the physiological status of the inoculant cells, the biotic and abiotic interactions in soil, soil properties, and substrate availability. Finally, we address the possibilities available to effectively manipulate the fate and activity of introduced microorganisms in relation to the main areas of their application. PMID:9184007

  14. Soil microbial activities beneath Stipa tenacissima L. and in surrounding bare soil

    NASA Astrophysics Data System (ADS)

    Novosadová, I.; Ruiz Sinoga, J. D.; Záhora, J.; Fišerová, H.

    2010-05-01

    Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa). These steppes show a higher degree of variability in composition and structure. Ecosystem functioning is strongly related to the spatial pattern of grass tussocks. Soils beneath S. tenacissima grass show higher fertility and improved microclimatic conditions, favouring the formation of "resource islands" (Maestre et al., 2007). On the other hand in "resource islands" and in surrounding bare soil exists the belowground zone of influence. The competition for water and resources between plants and microorganisms is strong and mediated trough an enormous variety of exudates and resource depletion intended to regulate soil microbial communities in the rhizosphere, control herbivory, encourage beneficial symbioses, and change chemical and physical properties in soil (Pugnaire et Armas, 2008). Secondary compounds and allelopathy restrict other species growth and contribute to patchy plant distribution. Active root segregation affects not only neighbour? growth but also soil microbial activities. The objective of this study was to assess the effect of Stipa tenacissima on the key soil microbial activities under controlled incubation conditions (basal and potential respiration; net nitrogen mineralization). The experimental plots were located in the province Almería in Sierra de los Filabres Mountains near the village Gérgal (southeast Spain) in the small catchment which is situated between 1090 - 1165 m a.s.l. The area with extent of 82 000 m2 is affected by soil degradation. The climate is semiarid Mediterranean. The mean annual rainfall is of about 240 mm mostly concentrated in autumn and spring. The mean annual temperature is 13.9° C. The studied soil has a loam to sandy clay texture and is classified as Lithosol (FAO-ISRIC and ISSS, 1998). The vegetation of these areas is an open steppe dominated by Stipa tenacissima. In February 2009 representative soil samples from the top 10 cm were taken beneath grass tussock and from bare soil. Soil samples in three replicates were incubated after rewetting with distilled water (basal microbial activities) and after rewetting with the glucose solution and with the mixture of glucose and peptone solution (potential microbial activities). The CO2, C2H4 evolved under controlled conditions (60% WHC, 24°C) during a 37-day aerobic incubation were determined. Ammonia and nitrate nitrogen were estimated in percolates after simulated rainfall (on the 16th day of incubation) and in the incubated soil samples at the end of incubation. Net ammonification and net nitrification rates were determined by subtracting initial soil mineral N from both mineral N in percolates plus final mineral N contents at 37th day. Basal, potential microbial respiration and net nitrification in the soils beneath S. tenacissima were, in general, not significantly different from the bare soils. The differences between plant-covered soil and bare soil in cumulative values of CO2 production and in amounts of accumulated NO3--N (net nitrification) were less than ± 10%. Greater differences were found in the net ammonification, which were higher beneath S. tenacissima, mainly in the control (basal activities) variant (about 38 %). Significantly less ethylene produced by microbial activity in soils beneath S. tenacissima after the addition of glucose indicates the dependence of rhizospheric microbial communities on available carbon compounds mainly from root exudates. It can be concluded, similarly as published Goberna et al., (2007), that the distribution of soil microbial properties in semi-arid Mediterranean ecosystems is not necessarily associated with the patchy plant distribution and that some microbial activities characteristics can be unexpectedly homogenous.

  15. Misidentification of soil bacteria by fatty acid methyl ester (FAME) and BIOLOG analyses

    Microsoft Academic Search

    N. Oka; P. G. Hartel; O. Finlay-Moore; J. Gagliardi; D. A. Zuberer; J. J. Fuhrmann; J. S. Angle; H. D. Skipper

    2000-01-01

    Fatty acid methyl ester (FAME) analysis is commonly used by soil scientists as a sole method for identifying soil bacteria.\\u000a We observed discrepancies with this method for identifying certain species of bacteria. Therefore, we used carbon substrate\\u000a oxidation patterns (BIOLOG) and some simple physical and chemical tests to determine the extent of these discrepancies. Identification\\u000a with FAME profiles gave false

  16. Biological soil crusts exhibit a dynamic response to seasonal rain and release from grazing with implications for soil stability

    USGS Publications Warehouse

    Jimenez, Aguilar A.; Huber-Sannwald, E.; Belnap, J.; Smart, D.R.; Arredondo, Moreno J.T.

    2009-01-01

    In Northern Mexico, long-term grazing has substantially degraded semiarid landscapes. In semiarid systems, ecological and hydrological processes are strongly coupled by patchy plant distribution and biological soil crust (BSC) cover in plant-free interspaces. In this study, we asked: 1) how responsive are BSC cover/composition to a drying/wetting cycle and two-year grazing removal, and 2) what are the implications for soil erosion? We characterized BSC morphotypes and their influence on soil stability under grazed/non-grazed conditions during a dry and wet season. Light- and dark-colored cyanobacteria were dominant at the plant tussock and community level. Cover changes in these two groups differed after a rainy season and in response to grazing removal. Lichens with continuous thalli were more vulnerable to grazing than those with semi-continuous/discontinuous thalli after the dry season. Microsites around tussocks facilitated BSC colonization compared to interspaces. Lichen and cyanobacteria morphotypes differentially enhanced resistance to soil erosion; consequently, surface soil stability depends on the spatial distribution of BSC morphotypes, suggesting soil stability may be as dynamic as changes in the type of BSC cover. Longer-term spatially detailed studies are necessary to elicit spatiotemporal dynamics of BSC communities and their functional role in biotically and abiotically variable environments. ?? 2009 Elsevier Ltd.

  17. Phosphatase activity in Antarctica soil samples as a biosignature of extant life

    NASA Astrophysics Data System (ADS)

    Sato, Shuji; Itoh, Yuki; Takano, Yoshinori; Fukui, Manabu; Kaneko, Takeo; Kobayashi, Kensei

    Microbial activities have been detected in such extreme terrestrial environments as deep lithosphere, a submarine hydrothermal systems, stratosphere, and Antarctica. Microorganisms have adapted to such harsh environments by evolving their biomolecules. Some of these biomolecules such as enzymes might have different characteristics from those of organisms in ordinary environments. Many biosignatures (or biomarkers) have been proposed to detect microbial activities in such extreme environments. A number of techniques are proposed to evaluate biological activities in extreme environments including cultivation methods, assay of metabolism, and analysis of bioorganic compounds like amino acids and DNA. Enzyme activities are useful signature of extant life in extreme environments. Among many enzymes, phosphatase could be a good indicator of biological activities, since phosphate esters are essential for all the living terrestrial organisms. In addition, alkaline phosphatase is known as a typical zinc-containing metalloenzyme and quite stable in environments. We analyzed phosphatase activities in Antarctica soil samples to see whether they can be used as biosignatures for extant life. In addition, we characterized phosphatases extracted from the Antarctica soil samples, and compared with those obtained from other types of environments. Antarctica surface environments are quite severe environments for life since it is extremely cold and dry and exposed to strong UV and cosmic rays. We tried to evaluate biological activities in Antarctica by measuring phosphatase activities. Surface soil samples are obtained at the Sites 1-8 near Showa Base in Antarctica during the 47th Japan Antarctic exploration mission in 2005-6. Activities of acid phosphatase (ACP) and alkaline phosphatase (ALP) are measured spectrophotometrically after mixing the powdered sample and p-nitrophenyl phosphate solution (pH 6.5 for ACP, pH 8.0 for ALP). ALP was characterized after extraction from soils with Tris-HCl buffer (pH 9.0), where the activity was measured fluorometrically with 4-methylumbelliferyl phosphate (pH 8.0) as a substance. The soil of Site 8 (near a penguin rookery) showed almost the same level of ACP and ALP activities as usual surface soil sampled in YNU campus, while the soil of Sites 1-7 showed much less activities. ALP in the extract from the soil of Site 8 was characterized. It showed the maximal at 338 K, while ALP from the campus soil showed the maximal at 358 K. Gel filtration chromatography showed that the ALP activity was found only in the fraction whose molecular weights were over 60000. The ALP activity was diminished with EDTA and was recovered with addition of zinc ion. The present results showed that zinc-containing metalloenzymes, which had lower optimum temperature than those in usual environments, are present in Antarctica soil. It was suggested that phosphatases are good bio-signatures for extant life in extreme environments.

  18. Teaching Organic Farming and Gardening: Resources for Instructors, 3rd Edition. Part 2 - Applied Soil Science

    E-print Network

    2015-01-01

    biological diversity and activity, increased pest and disease incidence Assessment Questions Key ResourcesBiological Communities www.blm.gov/nstc/soil/index.html Part 2 – 120 | Unit 2.3 Soil Biology & Ecology Resources

  19. Ferromagnetic nanoparticles containing biologically active alkanolamines: preparation and properties

    Microsoft Academic Search

    I. Segal; A. Zablotskaya; E. Lukevics; M. Maiorov; D. Zablotsky

    2005-01-01

    The objective of the present study is to investigate the possibility of sorption on ultrafine magnetic particles of some model biologically active organosilicon alkanolamines, structural analogs of natural biologically active substances, choline and colamine, with increased lipophilicity. Double-coated ferromagnetic samples containing oleic acid, as a first layer, and organosilicon alcanolamines, as a second layer, were obtained and characterized by their

  20. ASSESSMENT OF GENOTOXIC ACTIVITY OF PETROLEUM HYDROCARBON-BIOREMEDIATED SOIL

    SciTech Connect

    BRIGMON, ROBIN

    2004-10-20

    The relationship between toxicity and soil contamination must be understood to develop reliable indicators of environmental restoration for bioremediation. Two bacterial rapid bioassays: SOS chromotest and umu-test with and without metabolic activation (S-9 mixture) were used to evaluate genotoxicity of petroleum hydrocarbon-contaminated soil following bioremediation treatment. The soil was taken from an engineered biopile at the Czor Polish oil refinery. The bioremediation process in the biopile lasted 4 years, and the toxicity measurements were done after this treatment. Carcinogens detected in the soil, polyaromatic hydrocarbons (PAHs), were reduced to low concentrations (2 mg/kg dry wt) by the bioremediation process. Genotoxicity was not observed for soils tested with and without metabolic activation by a liver homogenate (S-9 mixture). However, umu-test was more sensitive than SOS-chromotest in the analysis of petroleum hydrocarbon-bioremediated soil. Analytical results of soil used in the bioassays confirmed that the bioremediation process reduced 81 percent of the petroleum hydrocarbons including PAHs. We conclude that the combined test systems employed in this study are useful tools for the genotoxic examination of remediated petroleum hydrocarbon-contaminated soil.

  1. [Effects of understory removal and nitrogen addition on the soil chemical and biological properties of Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land].

    PubMed

    Lin, Gui-Gang; Zhao, Qiong; Zhao, Lei; Li, Hui-Chao; Zeng, De-Hui

    2012-05-01

    A full factorial experiment was conducted to study the effects of understory removal and nitrogen addition (8 g x m(-2)) on the soil NO(3-)-N and NH(4+)-N concentrations, potential net nitrogen mineralization rate (PNM) and nitrification rate (PNN), microbial biomass C (MBC) and N (MBN), MBC/MBN, urease and acid phosphomonoesterase activities, and Olsen-P concentration in a Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land during a growth season. Understory removal decreased the soil NH(4+)-N concentration, PNM, MBC, and MBN/MBN significantly, increased the soil Olsen-P concentration, but had little effects on the soil NO(3-)-N concentration, PNN, and urease and acid phosphomonoesterase activities. Nitrogen addition increased the soil NO(3-)-N concentration, PNM and PNN significantly, but had little effects on the other test properties. The interaction between understory removal and nitrogen addition had significant effects on the soil NH(4+)-N concentration, but little effects on the soil NO(3-)-N concentration. However, the soil NO(3-)-N concentration in the plots of understory removal with nitrogen addition was increased by 27%, compared with the plots of nitrogen addition alone, which might lead to the leaching of NO3-. It was suggested that understory vegetation could play an important role in affecting the soil chemical and biological properties in Mongolian pine plantations, and hence, the importance of understory vegetation should not be neglected when the forest management and restoration were implemented. PMID:22919826

  2. Comparison of Soil Properties and Microbial Activities between Air-Dried and Rewetted Desert and Oasis Soils in Northwest China

    Microsoft Academic Search

    Chen-Hua Li; Yan Li; Li-Song Tang

    2011-01-01

    An air-drying and rewetting (AW) experiment was used to examine the responses of soil properties and microbial activities to abrupt alteration of water availability between desert and oasis soils in northwest China. The results revealed that AW increased soil pH and available nitrogen and phosphorus but decreased soil organic matter in the desert, while available phosphorus increased and available nitrogen

  3. Soil microbial activity and functional diversity changed by compaction, poultry litter and cropping in a claypan soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changes in soil physical characteristics induced by soil compaction may alter soil microhabitats and, therefore, play a significant role in governing soil microorganisms and their activities. Laboratory incubation and field experiments were conducted in 2001 and 2002 to investigate the effects of so...

  4. Short-term parasite-infection alters already the biomass, activity and functional diversity of soil microbial communities

    NASA Astrophysics Data System (ADS)

    Li, Jun-Min; Jin, Ze-Xin; Hagedorn, Frank; Li, Mai-He

    2014-11-01

    Native parasitic plants may be used to infect and control invasive plants. We established microcosms with invasive Mikania micrantha and native Coix lacryma-jobi growing in mixture on native soils, with M. micrantha being infected by parasitic Cuscuta campestris at four intensity levels for seven weeks to estimate the top-down effects of plant parasitism on the biomass and functional diversity of soil microbial communities. Parasitism significantly decreased root biomass and altered soil microbial communities. Soil microbial biomass decreased, but soil respiration increased at the two higher infection levels, indicating a strong stimulation of soil microbial metabolic activity (+180%). Moreover, a Biolog assay showed that the infection resulted in a significant change in the functional diversity indices of soil microbial communities. Pearson correlation analysis indicated that microbial biomass declined significantly with decreasing root biomass, particularly of the invasive M. micrantha. Also, the functional diversity indices of soil microbial communities were positively correlated with soil microbial biomass. Therefore, the negative effects on the biomass, activity and functional diversity of soil microbial community by the seven week long plant parasitism was very likely caused by decreased root biomass and root exudation of the invasive M. micrantha.

  5. Dehydrogenase activity of forest soils depends on the assay used

    NASA Astrophysics Data System (ADS)

    Januszek, Kazimierz; D?uga, Joanna; Socha, Jaros?aw

    2015-01-01

    Dehydrogenases are exclusively intracellular enzymes, which play an important role in the initial stages of oxidation of soil organic matter. One of the most frequently used methods to estimate dehydrogenase activity in soil is based on the use of triphenyltetrazolium chloride as an artificial electron acceptor. The purpose of this study was to compare the activity of dehydrogenases of forest soils with varied physicochemical properties using different triphenyltetrazolium chloride assays. The determination was carried out using the original procedure by Casida et al., a modification of the procedure which involves the use of Ca(OH)2 instead of CaCO3, the Thalmann method, and the assay by Casida et al. without addition of buffer or any salt. Soil dehydrogenase activity depended on the assay used. Dehydrogenase determined by the Casida et al. method without addition of buffer or any salt correlated with the pH values of soils. The autoclaved strongly acidic samples of control soils showed high concentrations of triphenylformazan, probably due to chemical reduction of triphenyltetrazolium chloride. There is, therefore, a need for a sterilization method other than autoclaving, ie a process that results in significant changes in soil properties, thus helping to increase the chemical reduction of triphenyltetrazolium chloride.

  6. Using thermal and spectroscopic (XANES) indices to understand the biological stability of soil organic matter.

    NASA Astrophysics Data System (ADS)

    Gillespie, A. W.; Sanei, H.; Diochon, A.; Tarnocai, C.; Janzen, H.; Regier, T. Z.; Gregorich, E.

    2014-12-01

    Soil organic matter (SOM) composition is a key property that underpins ecosystem productivity. Understanding its physical, chemical and biological properties is important for evaluating its role in carbon (C) and nutrient cycling in terrestrial ecosystems. In particular, the stability of SOM (i.e., resistance to microbial degradation) has important implications in ecosystem processes, including nutrient cycling, emission of greenhouse gases from soil, and C sequestration. Thus there is interest in developing new ways to measure and quantify the labile and stable forms of soil organic carbon. In this presentation, we describe the combined use of thermal decomposition methods based on pyrolysis, and chemical properties using X-ray absorption spectroscopy (XAS), to describe the stability of soil organic matter. Soils (n=81) for this study were obtained from a wide geographical range and management practices. Controlled respiration studies were conducted on the soils to determine the biodegradability of organic C after 98 days. In the thermal analysis, the sample is subjected to a temperature ramp and pyrolyzed/volatilized organic C was recorded as a function of temperature. Analysis by XAS provided information on the types of C functional groups present in a soil sample. We show that biological stability is well described using a two component model which included thermal stability and C composition chemistry.

  7. Bacterial communities and enzyme activities of PAHs polluted soils.

    PubMed

    Andreoni, V; Cavalca, L; Rao, M A; Nocerino, G; Bernasconi, S; Dell'Amico, E; Colombo, M; Gianfreda, L

    2004-11-01

    Three soils (i.e. a Belgian soil, B-BT, a German soil, G, and an Italian agricultural soil, I-BT) with different properties and hydrocarbon-pollution history with regard to their potential to degrade phenanthrene were investigated. A chemical and microbiological evaluation of soils was done using measurements of routine chemical properties, bacterial counts and several enzyme activities. The three soils showed different levels of polycyclic aromatic hydrocarbons (PAHs), being their contamination strictly associated to their pollution history. High values of enzyme activities and culturable heterotrophic bacteria were detected in the soil with no or negligible presence of organic pollutants. Genetic diversity of soil samples and enrichment cultures was measured as bands on denaturing gradient gel electrophoresis (DGGE) of amplified 16S rDNA sequences from the soil and enrichment community DNAs. When analysed by Shannon index (H'), the highest genetic biodiversity (H'=2.87) was found in the Belgian soil B-BT with a medium-term exposition to PAHs and the poorest biodiversity (H'=0.85) in the German soil with a long-term exposition to alkanes and PAHs and where absence, or lower levels of enzyme activities were measured. For the Italian agricultural soil I-BT, containing negligible amounts of organic pollutants but the highest Cu content, a Shannon index=2.13 was found. The enrichment of four mixed cultures capable of degrading solid phenanthrene in batch liquid systems was also studied. Phenanthrene degradation rates in batch systems were culture-dependent, and simple (one-slope) and complex (two-slope) kinetic behaviours were observed. The presence of common bands of microbial species in the cultures and in the native soil DNA indicated that those strains could be potential in situ phenanthrene degraders. Consistent with this assumption are the decrease of PAH and phenanthrene contents of Belgian soil B-BT and the isolation of phenanthrene-degrading bacteria. From the fastest phenanthrene-degrading culture C(B-BT), representative strains were identified as Achromobacter xylosoxidans (100%), Methylobacterium sp. (99%), Rhizobium galegae (99%), Rhodococcus aetherovorans (100%), Stenotrophomonas acidaminiphila (100%), Alcaligenes sp. (99%) and Aquamicrobium defluvium (100%). DGGE-profiles of culture C(B-BT) showed bands attributable to Rhodococcus, Achromobacter, Methylobacterium rhizobium, Alcaligenes and Aquamicrobium. The isolation of Rhodococcus aetherovorans and Methylobacterium sp. can be consistent with the hypothesis that different phenanthrene-degrading strategies, cell surface properties, or the presence of xenobiotic-specific membrane carriers could play a role in the uptake/degradation of solid phenanthrene. PMID:15331267

  8. Metal Toxicity Affects Fungal and Bacterial Activities in Soil Differently

    PubMed Central

    Rajapaksha, R. M. C. P.; Tobor-Kap?on, M. A; Bĺĺth, E.

    2004-01-01

    Although the toxic effect of heavy metals on soil microorganism activity is well known, little is known about the effects on different organism groups. The influence of heavy metal addition on total, bacterial, and fungal activities was therefore studied for up to 60 days in a laboratory experiment using forest soil contaminated with different concentrations of Zn or Cu. The effects of the metals differed between the different activity measurements. During the first week after metal addition, the total activity (respiration rate) decreased by 30% at the highest level of contamination and then remained stable during the 60 days of incubation. The bacterial activity (thymidine incorporation rate) decreased during the first days with the level of metal contamination, resulting in a 90% decrease at the highest level of contamination. Bacterial activity then slowly recovered to values similar to those of the control soil. The recovery was faster when soil pH, which had decreased due to metal addition, was restored to control values by liming. Fungal activity (acetate-in-ergosterol incorporation rate) initially increased with the level of metal contamination, being up to 3 and 7 times higher than that in the control samples during the first week at the highest levels of Zn and Cu addition, respectively. The positive effect of metal addition on fungal activity then decreased, but fungal activity was still higher in contaminated than in control soil after 35 days. This is the first direct evidence that fungal and bacterial activities in soil are differently affected by heavy metals. The different responses of bacteria and fungi to heavy metals were reflected in an increase in the relative fungal/bacterial ratio (estimated using phospholipid fatty acid analysis) with increased metal load. PMID:15128558

  9. Leaching of radionuclides from activated soil into groundwater.

    PubMed

    La Torre, F P; Silari, M

    2015-05-01

    Soil samples collected from the CERN site were irradiated by secondary radiation from the 400 GeV/c SPS proton beam at the H4IRRAD test area. Water samples were also irradiated at the same time. Detailed gamma spectrometry measurements and water scintillation analysis were performed to measure the radioactivity induced in the samples. FLUKA Monte Carlo simulations were performed to benchmark the induced radioactivity in the samples and to estimate the amount of tritium produced in the soil. Two leaching procedures were used and compared to quantify the radioactivity leached by water from the activated soil. The amount of tritium coming from both the soil moisture and the soil bulk was estimated. The present results are compared with literature data for the leaching of (3)H and (22)Na. PMID:25703432

  10. DYNAMICS OF SOIL FLORA AND FAUNA IN BIOLOGICAL CONTROL OF SOIL INHABITING PLANT PATHOGENS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cropland soil, which is comprised of spermosphere, rhizosphere and bulk soil, is populated by a wide array of microbial inhabitants. These microbial inhabitants include the microflora, represented by bacteria, actinomyces, archaea, fungi and algae and the micro- and mesofauna, such as protozoa, ...

  11. Activation Energy of Extracellular Enzymes in Soils from Different Biomes

    PubMed Central

    Steinweg, J. Megan; Jagadamma, Sindhu; Frerichs, Joshua; Mayes, Melanie A.

    2013-01-01

    Enzyme dynamics are being incorporated into soil carbon cycling models and accurate representation of enzyme kinetics is an important step in predicting belowground nutrient dynamics. A scarce number of studies have measured activation energy (Ea) in soils and fewer studies have measured Ea in arctic and tropical soils, or in subsurface soils. We determined the Ea for four typical lignocellulose degrading enzymes in the A and B horizons of seven soils covering six different soil orders. We also elucidated which soil properties predicted any measurable differences in Ea. ?-glucosidase, cellobiohydrolase, phenol oxidase and peroxidase activities were measured at five temperatures, 4, 21, 30, 40, and 60°C. Ea was calculated using the Arrhenius equation. ?-glucosidase and cellobiohydrolase Ea values for both A and B horizons in this study were similar to previously reported values, however we could not make a direct comparison for B horizon soils because of the lack of data. There was no consistent relationship between hydrolase enzyme Ea and the environmental variables we measured. Phenol oxidase was the only enzyme that had a consistent positive relationship between Ea and pH in both horizons. The Ea in the arctic and subarctic zones for peroxidase was lower than the hydrolases and phenol oxidase values, indicating peroxidase may be a rate limited enzyme in environments under warming conditions. By including these six soil types we have increased the number of soil oxidative enzyme Ea values reported in the literature by 50%. This study is a step towards better quantifying enzyme kinetics in different climate zones. PMID:23536898

  12. Activated Sludge. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Boe, Owen K.; Klopping, Paul H.

    This student manual contains the textual material for a seven-lesson unit on activated sludge. Topic areas addressed in the lessons include: (1) activated sludge concepts and components (including aeration tanks, aeration systems, clarifiers, and sludge pumping systems); (2) activated sludge variations and modes; (3) biological nature of activated

  13. Phorbol Esters: Structure, Biological Activity, and Toxicity in Animals

    Microsoft Academic Search

    Gunjan Goel; Harinder P. S. Makkar; George Francis; Klaus Becker

    2007-01-01

    Phorbol esters are the tetracyclic diterpenoids generally known for their tumor promoting activity. The phorbol esters mimic the action of diacyl glycerol (DAG), activator of protein kinase C, which regulates different signal transduction pathways and other cellular metabolic activities. They occur naturally in many plants of the family Euphorbiacaeae and Thymelaeaceae. The biological activities of the phorbol esters are highly

  14. Biological suppressiveness against sugarcane poor root syndrome in Queensland soils

    Microsoft Academic Search

    R. G. Birch

    1986-01-01

    Poor root syndrome (PRS) is a recently recognised disease of sugarcane causing serious yield reductions and harvesting problems\\u000a in high rainfall regions of North Queensland. The primary pathogens are Pythium graminicola causing destruction of fine roots and an unnamed Oomycete causing flaccid rot of primary roots. Physical and chemical soil\\u000a treatments have not provided economic control. So a search was

  15. Effects of Cd and Pb pollution on soil enzymatic activities and soil microbiota

    Microsoft Academic Search

    Shuqing Liu; Zhixin Yang; Xiaomin Wang; Xiaogui Zhang; Rutai Gao; Xia Liu

    2007-01-01

    Based on a representative sampling method and pot experiment with different concentrations of Cd and Pd, the enzymatic activities\\u000a (urease, phosphatase, catalase, invertase), population of bacteria, fungus and actinomycete in the soil, the Cd and Pd pollution\\u000a status of soil samples (from the wastewater-irrigated area of Baoding suburb) were appraised. Unitary linear and nonlinear\\u000a curve-fitting optimization models were applied in

  16. Land Data Assimilation Activities in Preparation of the NASA Soil Moisture Active Passive (SMAP) Mission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Slated for launch in 2013, the NASA Soil Moisture Active/Passive mission represents a generational advance in our ability to globally observe time and space variations in surface soil moisture fields. The SMAP mission concept is based on the integrated use of L-band active radar and passive radiome...

  17. Biological and Molecular Structure Analyses of the Controls on Soil Organic Matter Dynamics.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A combination of biological analysis, such as incubation and microbial biomass determination, 13C and 14C tracers, soil fractionation, and matrix analysis (LF, POM, silt, and clay) with molecular structure analysis (py-MBMS) on long-term sites with a C3 ' C4 crop switch provided the tools for determ...

  18. HYDROGEN PEROXIDE DECAY IN WATERS WITH SUSPENDED SOILS: EVIDENCE FOR BIOLOGICALLY MEDIATED PROCESSES

    EPA Science Inventory

    Hydrogen peroxide decay studies have been conducted in suspensions of several well-characterized soils and in natural water samples. inetic and product studies indicated that the decay was biologically mediated and could be described by psuedo first-order rate expressions. t an i...

  19. METHODS FOR EVALUATING THE BIOLOGICAL IMPACT OF POTENTIALLY TOXIC WASTE APPLIED TO SOILS

    EPA Science Inventory

    The study was designed to evaluate two methods that can be used to estimate the biological impact of organics and inorganics that may be in wastes applied to land for treatment and disposal. The two methods were the contact test and the artificial soil test. The contact test is a...

  20. Soil Biology & Biochemistry 38 (2006) 30353040 Biotic interactions in Antarctic terrestrial ecosystems: Are they a factor?

    E-print Network

    Wall, Diana

    2006-01-01

    interactions; Antarctica; Soil ecology; Terrestrial ecosystems; Invertebrates; Microbiology; Lichens; Abiotic; Cowan and Ah Tow, 2004; Bergstrom et al., 2006). Biological knowledge of eastern Antarctica (e the Southern Cross British Antarctic Expedition (1898­1900) (e.g. Carpenter, 1902), and cover- age now extends

  1. Soil Biological and Chemical Properties in Restored Perennial Grassland in California

    Microsoft Academic Search

    M. Potthoff; L. E. Jackson; K. L. Steenwerth; I. Ramirez; M. R. Stromberg; D. E. Rolston

    2005-01-01

    Restoration of California native perennial grassland is often initiated with cultivation to reduce the density and cover of non-native annual grasses before seeding with native perennials. Tillage is known to adversely impact agriculturally cultivated land; thus changes in soil biological functions, as indicated by carbon (C) turnover and C reten- tion, may also be negatively affected by these restoration techniques.

  2. Effects of Altered Temperature and Precipitation on Desert Protozoa Associated with Biological Soil Crusts

    E-print Network

    Neher, Deborah A.

    -third of the earth's land surface area. Global circulation models predict overall temperatures in the southwestEffects of Altered Temperature and Precipitation on Desert Protozoa Associated with Biological Soil and test the response of protozoa to increased temperature and precipitation as is predicted by some global

  3. Determination of mercury in soils and biological matrices by the vanadium pentoxide digestion procedure

    Microsoft Academic Search

    M. Malaiyandi; J. P. Barrette

    1974-01-01

    The wet digestion procedure using catalytic amounts of vanadium pentoxide with sulfuric-nitric acid mixture developed in this laboratory for the analysis of mercury in cereals is extended to other biological substrates and soils. Investigations of the different parameters, such as temperature and concentration of vanadium pentoxide on the oxidation process indicate that 0.20 g of vanadium pentoxide was adequate to

  4. Non-biological fractionation of stable Ca isotopes in soils of the Atacama Desert, Chile

    E-print Network

    Amundson, Ronald

    Non-biological fractionation of stable Ca isotopes in soils of the Atacama Desert, Chile Stephanie elements over time, or (b) isotopic fractionation of all three elements during downward transport. We.4 in CaSO4. The overall depth trend in Ca isotopes is reproduced by a model of isotopic fractionation

  5. Modelling and interpreting biologically crusted dryland soil sub-surface structure using automated micropenetrometry

    NASA Astrophysics Data System (ADS)

    Hoon, Stephen R.; Felde, Vincent J. M. N. L.; Drahorad, Sylvie L.; Felix-Henningsen, Peter

    2015-04-01

    Soil penetrometers are used routinely to determine the shear strength of soils and deformable sediments both at the surface and throughout a depth profile in disciplines as diverse as soil science, agriculture, geoengineering and alpine avalanche-safety (e.g. Grunwald et al. 2001, Van Herwijnen et al. 2009). Generically, penetrometers comprise two principal components: An advancing probe, and a transducer; the latter to measure the pressure or force required to cause the probe to penetrate or advance through the soil or sediment. The force transducer employed to determine the pressure can range, for example, from a simple mechanical spring gauge to an automatically data-logged electronic transducer. Automated computer control of the penetrometer step size and probe advance rate enables precise measurements to be made down to a resolution of 10's of microns, (e.g. the automated electronic micropenetrometer (EMP) described by Drahorad 2012). Here we discuss the determination, modelling and interpretation of biologically crusted dryland soil sub-surface structures using automated micropenetrometry. We outline a model enabling the interpretation of depth dependent penetration resistance (PR) profiles and their spatial differentials using the model equations, ? {}(z) ={}? c0{}+? 1n[? n{}(z){}+anz + bnz2] and d? /dz = ? 1n[d? n(z) /dz{} {}+{}Frn(z)] where ? c0 and ? n are the plastic deformation stresses for the surface and nth soil structure (e.g. soil crust, layer, horizon or void) respectively, and Frn(z)dz is the frictional work done per unit volume by sliding the penetrometer rod an incremental distance, dz, through the nth layer. Both ? n(z) and Frn(z) are related to soil structure. They determine the form of ? {}(z){} measured by the EMP transducer. The model enables pores (regions of zero deformation stress) to be distinguished from changes in layer structure or probe friction. We have applied this method to both artificial calibration soils in the laboratory, and in-situ field studies. In particular, we discuss the nature and detection of surface and buried (fossil) subsurface Biological Soil Crusts (BSCs), voids, macroscopic particles and compositional layers. The strength of surface BSCs and the occurrence of buried BSCs and layers has been detected at sub millimetre scales to depths of 40mm. Our measurements and field observations of PR show the importance of morphological layering to overall BSC functions (Felde et al. 2015). We also discuss the effect of penetrometer shaft and probe-tip profiles upon the theoretical and experimental curves, EMP resolution and reproducibility, demonstrating how the model enables voids, buried biological soil crusts, exotic particles, soil horizons and layers to be distinguished one from another. This represents a potentially important contribution to advancing understanding of the relationship between BSCs and dryland soil structure. References: Drahorad SL, Felix-Henningsen P. (2012) An electronic micropenetrometer (EMP) for field measurements of biological soil crust stability, J. Plant Nutr. Soil Sci., 175, 519-520 Felde V.J.M.N.L., Drahorad S.L., Felix-Henningsen P., Hoon S.R. (2015) Ongoing oversanding induces biological soil crust layering - a new approach for BSC structure elucidation determined from high resolution penetration resistance data (submitted) Grunwald, S., Rooney D.J., McSweeney K., Lowery B. (2001) Development of pedotransfer functions for a profile cone penetrometer, Geoderma, 100, 25-47 Van Herwijnen A., Bellaire S., Schweizer J. (2009) Comparison of micro-structural snowpack parameters derived from penetration resistance measurements with fracture character observations from compression tests, Cold Regions Sci. {& Technol.}, 59, 193-201

  6. The NASA Soil Moisture Active Passive (SMAP) mission: Overview

    Microsoft Academic Search

    Peggy O'Neill; Dara Entekhabi; Eni G. Njoku; Kent H. Kellogg

    2010-01-01

    The Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey. Its mission design consists of L-band radiometer and radar instruments sharing a rotating 6-m mesh reflector antenna to provide high-resolution and high-accuracy global maps of soil moisture and freeze\\/thaw state every 2-3

  7. Study of seleniferous soils using instrumental neutron activation analysis.

    PubMed

    Srivastava, Alok; Bains, G S; Acharya, R; Reddy, A V R

    2011-05-01

    Soil samples from the seleniferous region of Punjab State in India were analyzed by instrumental neutron activation analysis (INAA) using reactor neutrons and high resolution ?-ray spectrometry. Samples were collected from three different depths namely surface, root and geological bed zones. Concentrations of 15 elements including selenium and arsenic were determined by relative method. For comparison purposes, soil samples collected from a non-seleniferous region were also analyzed. PMID:21334213

  8. Summary Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and

    E-print Network

    Cohen, Ronald C.

    in the soil carbon pool may significantly affect the global carbon cycle and climate system. Soil respiration may accelerate global warming by acting as a positive feed- back in the global carbon cycle (Jenkinson

  9. Combined Passive Active Soil Moisture Observations During CLASIC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important issue in advancing higher spatial resolution and better accuracy in soil moisture remote sensing is the integration of active and passive observations. In an effort to address these questions an airborne passive/active L-band system (PALS) was flown as part of CLASIC in Oklahoma over th...

  10. Comparative Resistance and Resilience of Soil Microbial Communities and Enzyme Activities in Adjacent Native Forest and Agricultural Soils

    Microsoft Academic Search

    Guilherme Chaer; Marcelo Fernandes; David Myrold; Peter Bottomley

    2009-01-01

    Degradation of soil properties following deforestation and long-term soil cultivation may lead to decreases in soil microbial\\u000a diversity and functional stability. In this study, we investigated the differences in the stability (resistance and resilience)\\u000a of microbial community composition and enzyme activities in adjacent soils under either native tropical forest (FST) or in\\u000a agricultural cropping use for 14 years (AGR). Mineral soil

  11. Ficus carica L. (Moraceae): Phytochemistry, Traditional Uses and Biological Activities

    PubMed Central

    Mawa, Shukranul; Husain, Khairana; Jantan, Ibrahim

    2013-01-01

    This paper describes the botanical features of Ficus carica L. (Moraceae), its wide variety of chemical constituents, its use in traditional medicine as remedies for many health problems, and its biological activities. The plant has been used traditionally to treat various ailments such as gastric problems, inflammation, and cancer. Phytochemical studies on the leaves and fruits of the plant have shown that they are rich in phenolics, organic acids, and volatile compounds. However, there is little information on the phytochemicals present in the stem and root. Reports on the biological activities of the plant are mainly on its crude extracts which have been proven to possess many biological activities. Some of the most interesting therapeutic effects include anticancer, hepatoprotective, hypoglycemic, hypolipidemic, and antimicrobial activities. Thus, studies related to identification of the bioactive compounds and correlating them to their biological activities are very useful for further research to explore the potential of F. carica as a source of therapeutic agents. PMID:24159359

  12. Proceedings of the California Forest Soils Council Conference on Forest Soils Biology

    E-print Network

    Standiford, Richard B.

    ..............................................................43 William L. Bigg Influence of Forest Harvesting on Soil Organisms and Decomposition in Western. Sparks Northern Flying Squirrels Mycophagy and Truffle Production in Fir Forests of Northern California

  13. Soil organic matter dynamics and microbial activity in a cropland and soil treated with wood ash containing charcoal

    NASA Astrophysics Data System (ADS)

    Omil, B.; Fonturbel, M. T.; Vega, J. A.; Balboa, M. A.; Merino, A.

    2012-04-01

    Wood ash is generated as a by-product of biomass combustion in power plants, and can be applied to soil to improve nutritional status and crop production. The application of mixed wood ash, a mixture of ash and charcoal, may also improve the SOM content and quality. The charcoal contained in mixed wood ash is a pyrogenic organic material, a heterogeneous mixture of thermally altered polymers with aromatic domains. This structure may favour oxidation, facilitating further microbial attack and generation of new SOM compounds. In addition, accelerated C mineralization of this material may also be due to the priming effect of the rhizosphere, which may even enhance the decomposition of more recalcitrant SOM. The study was carried out in a field devoted to cereal crops during the last few decades. The soil was acidic (pH 4.5) with a low SOC content (3 %). The experiment was based on a randomised block design with four replicates. Each block included the following four treatments: Control, 16 Mg fly wood ash, 16 Mg mixed wood ash and 32 Mg mixed wood ash ha-1. The ash used in the study was obtained from a thermal power plant and was mainly derived from the combustion of Pinus radiata bark. The changes in SOM were monitored over two years by solid state 13C CPMAS NMR and Differential Scanning Calorimetry (DSC). The changes in microbial activity were studied by analysis of microbial biomass C and basal respiration. The soil bacterial community was studied by the Biolog method. Both 13 C-CPMAS NMR spectra and DSC curves revealed that the SOM in the treated soils displayed a higher degree of aromaticity than in the untreated soils, indicating a gain in more stable SOM compounds. However, both methods also revealed increases in other labile C compounds. Microbial biomass and soil respiration increased significantly as a result of these effects and possibly also due to a priming effect. The treatments also led to increases in the functional diversity indices. The amended soils showed greater utilization of substrate and a faster response. The ability of soil bacteria to utilize different C resources was also greatly altered. Greater utilization of carbohydrates, carboxylic acids, amino acid and amines was observed.

  14. Stratification of soil organic matter and its importance on soil and water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic matter is a key component of soil quality that sustains many important soil functions by providing the energy, substrates, and biological diversity to support biological activity, which affects aggregation (important for habitat space, oxygen supply, and preventing soil erosion), infilt...

  15. Biological Remediation of Soil: An Overview of Global Market and Available Technologies

    Microsoft Academic Search

    Ajay Singh; Ramesh C. Kuhad; Owen P. Ward

    \\u000a Due to a wide range of industrial and agricultural activities, a high number of chemical contaminants is released into the\\u000a environment, causing a significant concern regarding potential toxicity, carcinogenicity, and potential for bioaccumulation\\u000a in living systems of various chemicals in soil. Although microbial activity in soil accounts for most of the degradation of\\u000a organic contaminants, chemical and physical mechanisms can

  16. Simulation of Viking biology experiments suggests smectites not palagonites, as martian soil analogues

    NASA Technical Reports Server (NTRS)

    Banin, A.; Margulies, L.

    1983-01-01

    An experimental comparison of palagonites and a smectite (montmorillonite) was performed in a simulation of the Viking Biology Labelled Release (LR) experiment in order to judge which mineral is a better Mars soil analog material (MarSAM). Samples of palagonite were obtained from cold weathering environments and volcanic soil, and the smectite was extracted from Wyoming Bentonite and converted to H or Fe types. Decomposition reaction kinetics were examined in the LR simulation, which on the Lander involved interaction of the martian soil with organic compounds. Reflectance spectroscopy indicated that smectites bearing Fe(III) in well-crystallized sites are not good MarSAMS. The palagonites did not cause the formate decomposition and C-14 emission detected in the LR, indicating that palagonites are also not good MarSAMS. Smectites, however, may be responsible for ion exchange, molecular adsorption, and catalysis in martian soil.

  17. Sensitive bioassay for detection of biologically active ricin in food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential use of ricin as an agent of biological warfare highlights the need to develop fast and effective methods to detect biologically active ricin. The current “gold standard” for ricin detection is an in vivo mouse bioassay; however, this method is not practical to test on a large number of...

  18. Effects of a soil conditioner on some physical and biological features of soils: results from a greenhouse study.

    PubMed

    Oztürk, H S; Türkmen, C; Erdogan, E; Baskan, O; Dengiz, O; Parlak, M

    2005-11-01

    A soil amendment substance-organic bio-stimulator, Terralyt Plus (TP), was used to observe its impact on the properties of clay loam (CL), sandy clay loam (SCL) and sandy loam (SL) soils and the growth of corn (Zea mays indentata L.) and wheat (Triticum aestivum ssp./vulgare Vill. v. lutescens) under greenhouse conditions. The diluted TP solutions (1:500, 1:1000 and 1:2000) were sprayed onto the soil surfaces. The wheat growth increased for CL and SCL with the application of TP at 1:1000. The highest dry weights were detected with 1:500 TP and corn in all the soils. Penetration resistance of CL containing corn increased with increasing TP concentration. TP was also effective in improving the aggregate stability for CL but not for the other soils. Catalase enzyme activity (CEA), soil evolution (SE) and the total aerobic bacterial population (TABP) were significantly increased (P<0.05) by spraying TP at 1:1000 onto CL. PMID:16084376

  19. The effect of burning on soil enzyme activities in natural grasslands in southern India

    Microsoft Academic Search

    Kurunthachalam Senthilkumar; Sellamuthu Manian; Karuthamuthu Udaiyan

    1997-01-01

    Soil amylase, cellulase, invertase and phosphatase activities were determined following wildfire in a savanna type grassland\\u000a in southern India. Activities of these enzymes increased substanially in burned soils compared to those in adjacent unburned\\u000a soils. Surface soil (0–10 cm) exhibited a greater increase in enzyme activities than subsurface soil (10–20 cm). Amylase activity\\u000a was more pronounced following fire than the

  20. Carbon exchange in biological soil crust communities under differential temperatures and soil water contents: implications for global change

    USGS Publications Warehouse

    Grote, Edmund E.; Belnap, Jayne; Housman, David C.; Sparks, Jed P.

    2010-01-01

    Biological soil crusts (biocrusts) are an integral part of the soil system in arid regions worldwide, stabilizing soil surfaces, aiding vascular plant establishment, and are significant sources of ecosystem nitrogen and carbon. Hydration and temperature primarily control ecosystem CO2 flux in these systems. Using constructed mesocosms for incubations under controlled laboratory conditions, we examined the effect of temperature (5-35 1C) and water content (WC, 20-100%) on CO2 exchange in light cyanobacterially dominated) and dark cyanobacteria/lichen and moss dominated) biocrusts of the cool Colorado Plateau Desert in Utah and the hot Chihuahuan Desert in New Mexico. In light crusts from both Utah and New Mexico, net photosynthesis was highest at temperatures 430 1C. Net photosynthesis in light crusts from Utah was relatively insensitive to changes in soil moisture. In contrast, light crusts from New Mexico tended to exhibit higher rates of net photosynthesis at higher soil moisture. Dark crusts originating from both sites exhibited the greatest net photosynthesis at intermediate soil water content (40-60%). Declines in net photosynthesis were observed in dark crusts with crusts from Utah showing declines at temperatures 425 1C and those originating from New Mexico showing declines at temperatures 435 1C. Maximum net photosynthesis in all crust types from all locations were strongly influenced by offsets in the optimal temperature and water content for gross photosynthesis compared with dark respiration. Gross photosynthesis tended to be maximized at some intermediate value of temperature and water content and dark respiration tended to increase linearly. The results of this study suggest biocrusts are capable of CO2 exchange under a wide range of conditions. However, significant changes in the magnitude of this exchange should be expected for the temperature and precipitation changes suggested by current climate models.

  1. Effects of de-icing salt on soil enzyme activity

    Microsoft Academic Search

    M. Güntner; B.-M. Wilke

    1983-01-01

    Effects of de-icing salt on dehydrogenase, urease, alkalihephosphatase and arylsulfatase activity ofOL andAh-horizons of a moder and a mull soil were investigated using a field experiment. Additions of 2.5 kg m-2 and 5.0 kg m-2 of de-icing salt reduced activities of most enzymes within four weeks. Eleven months after salt addition there was nearly no reduction of enzyme activity to

  2. Biofilm processes in biologically active carbon water purification

    Microsoft Academic Search

    David R. Simpson

    2008-01-01

    This review paper serves to describe the composition and activity of a biologically active carbon (BAC) biofilm used in water purification. An analysis of several physical–chemical, biochemical and microbiological methods (indicators) used to characterize the BAC biofilm's composition and activity is provided. As well, the ability of the biofilm to remove and biodegrade waterborne organic substances and pollutants will be

  3. Influence of Soil Moisture on Microbial Activity in a Primary Acidification of Pyritic Soils

    NASA Astrophysics Data System (ADS)

    Ueno, K.; Adachi, T.

    2004-12-01

    Soil moisture had a grate influence on soil acidification in pyritic soils. The acidification was occurred by chemical and bacterial processes of pyrite oxidation. It was reported that the bacterial oxidation was accelerated by soil moisture at near the condition of plastic limited. We investigated the accelerated soil moisture condition by matric potential and changes of bacterial activity using a soil taken from polder land of the Lake Nakaumi. Six levels of soil moisture conditions were prepared by drying. The samples were incubated at 30oC with keeping these moistures, and populations of Gram-positive and -negative bacteria (GPB and GNB) and Thiobacillus ferrooxidans (total, adsorbed and free forms) were determined. Soil acidification was accelerated at the moisture range from -6.0kPa to -35kPa while drying at 5.4g/h of evaporation rate. Samples drying at 12.0g/h ceased acidifying over -35kPa. On the other hand, a drop of pH value was accelerated at -35kPa when the samples was kept under their moisture conditions. The moisture condition seemed to be suitable for bacterial oxidation. The major bacteria under most of the moisture conditions were GPB, but T. ferrooxidans, one of GNB, was predominated at -35kPa. Under this moisture condition, the growth rate of T. ferrooxidans was highest and the population of GPB decreased during the exponential growth stage of T. ferrooxidans. Acidification of the soil seemed to be depending on proliferation of T. ferrooxidans not on the cell number of T. ferrooxidans. The growth rate of both absorbed and free forms of T. ferrooxidans was highest at -35kPa of all soil moisture conditions. The survival rate of T. ferrooxidans was highest at -3.5kPa and that of the free forms decreased at -35kPa. At -3,000kPa the absorbed forms of T. ferrooxidans had very small population and then decreased. The free forms were not detected. These data indicated that growth habitat of T. ferrooxidans were influenced by soil moisture. The accelerated moisture condition of -35kPa had a uniqueness on the bacterial populations and was suitable for proliferation of T. ferrooxidans. These results showed that high growth rate of T. ferrooxidans had a great influence on high rate of acidification in pyritic soils. The mechanism supposed to be that motility of the bacteria was influenced by shrinkage level of soil matrix and also that the environment was suitable for getting their energy to keep them alive.

  4. THE BIOLOGICAL ACTIVITY OF CAROTENOID METABOLITES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review deals with biologically formed metabolites of carotenoids, other than the retinoids such as retinol (vitamin A), retinal and retinoic acid. These latter compounds are formed by central cleavage of beta-carotene. However, there is increasing evidence that other, non-central cleavage mecha...

  5. Systematically biological prioritizing remediation sites based on datasets of biological investigations and heavy metals in soil

    NASA Astrophysics Data System (ADS)

    Lin, Wei-Chih; Lin, Yu-Pin; Anthony, Johnathen

    2015-04-01

    Heavy metal pollution has adverse effects on not only the focal invertebrate species of this study, such as reduction in pupa weight and increased larval mortality, but also on the higher trophic level organisms which feed on them, either directly or indirectly, through the process of biomagnification. Despite this, few studies regarding remediation prioritization take species distribution or biological conservation priorities into consideration. This study develops a novel approach for delineating sites which are both contaminated by any of 5 readily bioaccumulated heavy metal soil contaminants and are of high ecological importance for the highly mobile, low trophic level focal species. The conservation priority of each site was based on the projected distributions of 6 moth species simulated via the presence-only maximum entropy species distribution model followed by the subsequent application of a systematic conservation tool. In order to increase the number of available samples, we also integrated crowd-sourced data with professionally-collected data via a novel optimization procedure based on a simulated annealing algorithm. This integration procedure was important since while crowd-sourced data can drastically increase the number of data samples available to ecologists, still the quality or reliability of crowd-sourced data can be called into question, adding yet another source of uncertainty in projecting species distributions. The optimization method screens crowd-sourced data in terms of the environmental variables which correspond to professionally-collected data. The sample distribution data was derived from two different sources, including the EnjoyMoths project in Taiwan (crowd-sourced data) and the Global Biodiversity Information Facility (GBIF) ?eld data (professional data). The distributions of heavy metal concentrations were generated via 1000 iterations of a geostatistical co-simulation approach. The uncertainties in distributions of the heavy metals were then quantified based on the overall consistency between realizations. Finally, Information-Gap Decision Theory (IGDT) was applied to rank the remediation priorities of contaminated sites in terms of both spatial consensus of multiple heavy metal realizations and the priority of specific conservation areas. Our results show that the crowd-sourced optimization algorithm developed in this study is effective at selecting suitable data from crowd-sourced data. By using this technique the available sample data increased to a total number of 96, 162, 72, 62, 69 and 62 or, that is, 2.6, 1.6, 2.5, 1.6, 1.2 and 1.8 times that originally available through the GBIF professionally-assembled database. Additionally, for all species considered the performance of models, in terms of test-AUC values, based on the combination of both data sources exceeded those models which were based on a single data source. Furthermore, the additional optimization-selected data lowered the overall variability, and therefore uncertainty, of model outputs. Based on the projected species distributions, our results revealed that around 30% of high species hotspot areas were also identified as contaminated. The decision-making tool, IGDT, successfully yielded remediation plans in terms of specific ecological value requirements, false positive tolerance rates of contaminated areas, and expected decision robustness. The proposed approach can be applied both to identify high conservation priority sites contaminated by heavy metals, based on the combination of screened crowd-sourced and professionally-collected data, and in making robust remediation decisions.

  6. Biology Research Activities: Teacher's Edition (with Answers).

    ERIC Educational Resources Information Center

    Newman, Barbara

    This book is part of the series "Explorations in Science" which contains enrichment activities for the general science curriculum. Each book in the series contains innovative and traditional projects for both the bright and average, the self-motivated, and those who find activity motivating. Each activity is self-contained and provides everything…

  7. Soil hydrological and soil property changes resulting from termite activity on agricultural fields in Burkina Faso

    NASA Astrophysics Data System (ADS)

    Mettrop, I.; Cammeraat, L. H.; Verbeeten, E.

    2009-04-01

    Termites are important ecosystem-engineers in subtropical and tropical regions. The effect of termite activity affecting soil infiltration is well documented in the Sahelian region. Most studies find increased infiltration rates on surfaces that are affected by termite activity in comparison to crusted areas showing non-termite presence. Crusted agricultural fields in the Sanmatenga region in Burkina Faso with clear termite activity were compared to control fields without visual ground dwelling termite activity. Fine scale rainfall simulations were carried out on crusted termite affected and control sites. Furthermore soil moisture change, bulk density, soil organic matter as well as general soil characteristics were studied. The top soils in the study area were strongly crusted (structural crust) after the summer rainfall and harvest of millet. They have a loamy sand texture underlain by a shallow sandy loam Bt horizon. The initial soil moisture conditions were significantly higher on the termite plots when compared to control sites. It was found that the amount of runoff produced on the termite plots was significantly higher, and also the volumetric soil moisture content after the experiments was significantly lower if compared to the control plots. Bulk density showed no difference whereas soil organic matter was significantly higher under termite affected areas, in comparison to the control plots. Lab tests showed no significant difference in hydrophobic behavior of the topsoil and crust material. Micro and macro-structural properties of the topsoil did not differ significantly between the termite sites and the control sites. The texture of the top 5 cm of the soil was also found to be not significantly different. The infiltration results are contradictory to the general literature, which reports increased infiltration rates after prolonged termite activity although mostly under different initial conditions. The number of nest entrances was clearly higher in the termite areas, but apparently did not significantly affect infiltration. The increased soil organic matter contents in the termite affected areas however, are as expected from literature, but did not improve soil aggregation which would be expected given the importance of organic matter in soil aggregation in this type of soils. One of the explanations for the reduced infiltration rates might be that termites bring clay from the finer textured subsoil to the surface to build casts over the organic material on the surface (mainly millet stems). It is speculated that the excavated clay material could be involved in crust formation, only present is in the upper 0.5 cm of the soil crust, which is enough to block pores in the crust surface, hampering infiltration. The topsoil aggregates are slaking under the summer rainfall and the increase in fine textured material, excavated by the termites, could be incorporated into the crust and reduce infiltration. Furthermore this specific effect might also be related to the type of termite involved, as impacts from ecosystem engineers on their environment is highly dependent on the specific species involved.

  8. Measurement of dinitrogen fixation by Biological soil crust (BSC) from the Sahelian zone: an isotopic method.

    NASA Astrophysics Data System (ADS)

    Ehrhardt, F.; Alavoine, G.; Bertrand, I.

    2012-04-01

    Amongst the described ecological roles of Biological Soil Crust, N fixation is of importance for soil fertility, especially in arid and semi-arid ecosystems with low inputs. In BSC, the quantification of N fixation fluxes using an indirect method is widespread, usually with the Acetylene Reduction Assay (ARA) which consists in measuring the nitrogenase activity through the process of acetylene reduction into ethylene. A converting factor, still discussed in the literature and greatly depending of the constitutive organisms of the BSC, is the tool used to convert the amount of reduced ethylene into quantitative fixed Nitrogen. The aim of this poster is to describe an isotopic direct method to quantify the atmospheric dinitrogen fixation fluxes in BSC, while minimizing the variability due to manipulations. Nine different BSC from the Sahelian zone were selected and placed in an incubation room at 28° C in dark and light conditions during three days, while moisture equivalent to pF=2 was regularly adjusted using the gravimetric method with needles and deionized water, in order to activate and reach a dynamic stability of their metabolisms. Subsequently, each crust was placed into a gas-tight glass vial for incubation with a reconstituted 15N2 enriched atmosphere (31.61 % atom 15N, while the proportion of each main gas present in the air was conserved, i.e. 78% N2, 21% O2 and 0.04% CO2). Principal difficulties are to guarantee the airtighness of the system, to avoid crust desiccation and to keep the crust metabolically active under stable conditions for six hours. Several tests were performed to determine the optimum time for 15N2 incubation. Three replicated control samples per crust were also stabilized for three days and then dried at 105° C, without any incubation with 15N2 enriched atmosphere. Total N and 15N were then measured in the grounded (80?m) and dried (105° C) crust, using a Flash EA elemental analyzer (Eurovector, Milan, Italy) coupled to a DeltaPlus Advantage mass spectrometer (Finnigan Thermo Fisher Scientific, Bremen, Germany). N2fixation fluxes were calculated from the difference between the amount of 15N in incubated and in control samples. Mean values ranged from 1.32.10-3 ± 1.02.10-4 to 8.47.10-2 ± 2.63.10-3 mgN.m-2.h-1. Concerning the variability, differences observed between crusts and between replicates are probably related to the characteristic of each crust as well as to field sampling which integrates the important heterogeneity and sensitivity of the material.

  9. Chemical Combination of Biologically Active Derivatives ofN-Acetylmuramoyl Dipeptide and Lipid-A, and Their Biological Activities

    Microsoft Academic Search

    Akira Hasegawa; Eiji Seki; Yushun Fujishima; Koji Kigawa; Makoto Kiso; Hideharu Ishida; Ichiro Azuma

    1986-01-01

    Chemical coupling of biologically active derivatives of N-acetyl-muramoyl dipeptide with a derivative related to the nonreducing sub-unit of lipid A was carried out using acyl groups as a spacer. The products exhibited efficient antitumor activity, as well as strong, immunoadjuvant activity.

  10. Combined use of GIS and environmental indicators for assessment of chemical, physical and biological soil degradation in a Spanish Mediterranean region.

    PubMed

    de Paz, José-Miguel; Sánchez, Juan; Visconti, Fernando

    2006-04-01

    Soil is one of the main non-renewable natural resources in the world. In the Valencian Community (Mediterranean coast of Spain), it is especially important because agriculture and forest biomass exploitation are two of the main economic activities in the region. More than 44% of the total area is under agriculture and 52% is forested. The frequently arid or semi-arid climate with rainfall concentrated in few events, usually in the autumn and spring, scarcity of vegetation cover, and eroded and shallow soils in several areas lead to soil degradation processes. These processes, mainly water erosion and salinization, can be intense in many locations within the Valencian Community. Evaluation of soil degradation on a regional scale is important because degradation is incompatible with sustainable development. Policy makers involved in land use planning require tools to evaluate soil degradation so they can go on to develop measures aimed at protecting and conserving soils. In this study, a methodology to evaluate physical, chemical and biological soil degradation in a GIS-based approach was developed for the Valencian Community on a 1/200,000 scale. The information used in this study was obtained from two different sources: (i) a soil survey with more than 850 soil profiles sampled within the Valencian Community, and (ii) the environmental information implemented in the Geo-scientific map of the Valencian Community digitised on an Arc/Info GIS. Maps of physical, chemical and biological soil degradation in the Valencian Community on a 1/200,000 scale were obtained using the methodology devised. These maps can be used to make a cost-effective evaluation of soil degradation on a regional scale. Around 29% of the area corresponding to the Valencian Community is affected by high to very high physical soil degradation, 36% by high to very high biological degradation, and 6% by high to very high chemical degradation. It is, therefore, necessary to draw up legislation and to establish the policy framework for actions focused on preventing soil degradation and conserving its productive potential. PMID:16171939

  11. Winter biotic activity and production of CO[sub 2] in Siberian soils: A factor in the greenhouse effect

    SciTech Connect

    Zimov, S.A.; Zimova, G.M.; Daviodov, S.P.; Daviodova, A.I.; Voropaev, Y.V.; Voropaeva, Z.V.; Prosiannikov, S.F.; Prosiannikova, O.V. (Pacific Inst. for Geography, Vladivostok (Russian Federation)); Semiletova, I.V. (Inst. of Chemistry, Vladivostok (Russian Federation)); Semiletov, I.P. (Pacific Oceanological Inst. Vladivostok (Russian Federation))

    1993-03-20

    Soil CO[sub 2] emissions at latitudes near 70[degrees]N in northeastern Siberia have been measured and occur at levels high enough to account for the observed winter maximum in atmospheric CO[sub 2] concentrations in this latitude. This CO[sub 2] is produced by biological activity at the bottom of the active layer above the permafrost. Ecological and anthropological factors may play a role in stimulating this CO[sub 2] emission. 35 refs., 3 figs.

  12. Combined effects of cadmium and butachlor on soil enzyme activities and microbial community structure

    Microsoft Academic Search

    Jinhua Wang; Yitong Lu; Guoqing Shen

    2007-01-01

    The combined effects of cadmium (Cd, 10 mg\\/kg of soil) and butachlor (5, 10 and 50 mg\\/kg of soil) on enzyme activities and\\u000a microbial community structure were assessed in phaeozem soil. The result showed that phosphatase activities were decreased\\u000a in soils with Cd (10 mg\\/kg of soil) alone whereas urease acitivities were unaffected by Cd. Urease and phosphatase activities\\u000a were significantly reduced by

  13. Effect of food waste compost on microbial population, soil enzyme activity and lettuce growth

    Microsoft Academic Search

    Jae-Jung Lee; Ro-Dong Park; Yong-Woong Kim; Jae-Han Shim; Dong-Hyun Chae; Yo-Sup Rim; Bo-Kyoon Sohn; Tae-Hwan Kim; Kil-Yong Kim

    2004-01-01

    The effect of food waste (FW) composted with MS® (Miraculous Soil Microorganisms) was compared with commercial compost (CC) and mineral fertilizer (MF) on bacterial and fungal populations, soil enzyme activities and growth of lettuce in a greenhouse. Populations of fungi and bacteria, soil biomass, and soil enzyme activities in the rhizosphere of FW treatments significantly increased compared to control (CON),

  14. Seasonal Dynamics of Enzymatic Activities and Functional Diversity in Soils under Different Organic Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil microbial activity and diversity fluctuate seasonally under annual organic amendment for improving soil quality. We investigated the effects of municipal compost (MC), poultry litter (PL), and cover crops of spring oats and red clover (RC) on soil enzyme activities, and soil bacterial community...

  15. The Soil Moisture Active and Passive (SMAP) Mission

    NASA Technical Reports Server (NTRS)

    Entekhabi, Dara; Nijoku, Eni G.; ONeill, Peggy E.; Kellogg, Kent H.; Crow, Wade T.; Edelstein, Wendy N.; Entin, Jared K.; Goodman, Shawn D.; Jackson, Thomas J.; Johnson, Joel; Kimball, John; Piepmeier, Jeffrey R.; Koster, Randal D.; McDonald, Kyle C.; Moghaddam, Mahta; Moran, Susan; Reichle, Rolf; Shi, J. C.; Spencer, Michael W.; Thurman, Samuel W.; Tsang, Leung; VanZyl, Jakob

    2009-01-01

    The Soil Moisture Active and Passive (SMAP) Mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council s Decadal Survey. SMAP will make global measurements of the moisture present at Earth's land surface and will distinguish frozen from thawed land surfaces. Direct observations of soil moisture and freeze/thaw state from space will allow significantly improved estimates of water, energy and carbon transfers between land and atmosphere. Soil moisture measurements are also of great importance in assessing flooding and monitoring drought. SMAP observations can help mitigate these natural hazards, resulting in potentially great economic and social benefits. SMAP soil moisture and freeze/thaw timing observations will also reduce a major uncertainty in quantifying the global carbon balance by helping to resolve an apparent missing carbon sink on land over the boreal latitudes. The SMAP mission concept would utilize an L-band radar and radiometer. These instruments will share a rotating 6-meter mesh reflector antenna to provide high-resolution and high-accuracy global maps of soil moisture and freeze/thaw state every two to three days. The SMAP instruments provide direct measurements of surface conditions. In addition, the SMAP project will use these observations with advanced modeling and data assimilation to provide deeper root-zone soil moisture and estimates of land surface-atmosphere exchanges of water, energy and carbon. SMAP is scheduled for a 2014 launch date

  16. Amazing Soil Stories: Adventure and Activity Book [and] Teacher's Guide to the Activity Book.

    ERIC Educational Resources Information Center

    California Association of Resource Conservation Districts, Sacramento.

    The student activity book offers a variety of written exercises and "hands on" experiments and demonstrations for students at the fourth grade level. The book begins with a cartoon story that follows the adventures of a student investigating a soil erosion crisis and what her community can do to prevent soil erosion. Interspersed within the story…

  17. The influence of soil heavy metals pollution on soil microbial biomass, enzyme activity, and community composition near a copper smelter

    Microsoft Academic Search

    YuanPeng Wang; JiYan Shi; Hui Wang; Qi Lin; XinCai Chen; YingXu Chen

    2007-01-01

    The environmental risk of heavy metal pollution is pronounced in soils adjacent to large industrial complexes. It is important to investigate the functioning of soil microorganisms in ecosystems exposed to long-term contamination by heavy metals. We studied the potential effects of heavy metals on microbial biomass, activity, and community composition in soil near a copper smelter in China. The results

  18. Effects of Single Chinese Fir and Mixed Leaf Litters on Soil Chemical, Microbial Properties and Soil Enzyme Activities

    Microsoft Academic Search

    Y. L. Hu; S. L. Wang; D. H. Zeng

    2006-01-01

    The quality of leaf litter can control decomposition processes and affect the nutrient availability for plant uptake. In this\\u000a study, we investigated the effect of single leaf litter (Chinese fir – Cunninghamia lamcealata (Lamb.) Hook) and mixed leaf litters (C. lamcealata, Liquidamba formosana Hance and Alnus cremastogyne Burk) on soil chemical properties, soil microbial properties and soil enzyme activities during

  19. Effects of plant species coexistence on soil enzyme activities and soil microbial community structure under Cd and Pb combined pollution

    Microsoft Academic Search

    Yang Gao; Pei Zhou; Liang Mao; Yueer Zhi; Chunhua Zhang; Wanjun Shi

    2010-01-01

    The relationship between plant species coexistence and soil microbial communities under heavy metal pollution has attracted much attention in ecology. However, whether plant species coexistence could offset the impacts of heavy metal combined pollution on soil microbial community structure and soil enzymes activities is not well studied. The modified ecological dose model and PCR-RAPD method were used to assess the

  20. Development of biological soil crusts and their influence on soil hydrology in the recultivation area of lignite open-cast mining district in Lower Lusatia (Germany)

    NASA Astrophysics Data System (ADS)

    Spröte, R.; Veste, M.; Fischer, T.; Raab, T.; Bens, O.; Hüttl, R. F.

    2012-04-01

    Cyanobacteria, green algae, mosses and lichens are often the first colonizers of substrate and initial soil surfaces. They are an important factor of initial soil formation as they stabilize the substrate and decrease erosion processes. Biological soil crusts accumulate the initial soil organic matter and provide nitrogen fixation. Once settled, the crusts influence the soil water regime by delaying or limiting infiltration through enhanced water repellency. Aim of this study was to compare the influence of biological soil crusts on soil hydrology under conditions on various substrates and of different ages in recultivated areas of the open-cast mining district of Lower Lusatia (Brandenburg, NE Germany) with various recultivation aims. In Brandenburg (NE Germany), where the climate is transitional between oceanic and continental and the summers are characterized by generally low of precipitation (mean annual rainfall 559 mm, mean annual temperature 9.3° C) open landscapes provide ideal conditions for biological soil crusts, e. g. on mobile sand dunes in former military training areas and in recultivation areas related to open-cast mining with initial soil development. Here biological soil crusts are commonly found (Spröte et al., 2010). At five study sites in recultivation areas with different reclamation approaches (natural development, pine reforestation, birch reforestation) we defined four types of biological soil crusts: i) cyanobacterial and green algae crusts on the soil surface with no vegetation where dominating sand grains were physically stabilized in their contact zones by this crust type (type 1), ii) cyanobacteria and green algae partially filled in the matrix pores and enmeshed sand grains between sparse vegetation cover (type 2), iii) biological soil crusts with mosses which covered most of the surface between the vegetation (type 3) and (iv) with soil lichens (type 4). We investigated the development of the amount of chlorophyll a which is an indicator for biomass productivity and depends from the species composition and crust type, and the water repellency index which shows the influence of biological soil crusts on hydrological parameters. Additionally, organic matter content (dry combustion) as well as soil pH (soil: H2O = 1:2.5) were determined. Texture was analysed by wet sieving and fractionation pipette method. At all study sites and for all crust types soil pH ranged between 7.2 to 4.7 and decreased from type 1 to type 4. Soil organic matter and chlorophyll a concentrations ranged from 0.3 and 1.7% and from 0.95 to 16.44 mg m-2, respectively, and increased from type 1 to type 4. With few exceptions, water repellency indices ranging between 1.0 and 1.85, followed this trend. Constrarily, infiltration rates decreased from type 1 to type 4. The cause for limited infiltration is the swelling of extracellular polysaccharides in the biological soil crusts (Fischer et al., 2010) and the influence of the particle size distribution and porosity of the substrate with a relatively high content of silt and clay at some study sites. Fischer, T., Veste, M., Wiehe, W. & Lange, P. (2010): Water repellency and pore clogging at early succesional stages of microbiotic crusts on inland dunes, Brandenburg, NE Germany. - Catena, 80, 47-52. Spröte, R.,Fischer, T., Veste, M., Raab, T., Wiehe, W., Lange, P., Bens, O., Hüttl, R.F. (2010): Biological topsoil crusts at early successional stages on Quaternary substrates dumped by mining in Brandenburg, NE Germany. Géomorphologie: relief, processus, environnement 4/2010: 359-370.

  1. Synthesis and biological activities of new halophenols.

    PubMed

    Zheng, FeiLang; Ban, ShuRong; Feng, XiuE; Zhao, ChengXiao; Du, GuanHua; Li, QingShan

    2013-03-01

    A series of new halophenols were synthesized, and their structures were established on the basis of 1H, 13C NMR and mass spectral data. All of the prepared compounds were screened for their in vitro protein tyrosine kinase (PTK) and vascular smooth muscle cell (VSMC) proliferation inhibitory activity. Twelve halophenols showed significant PTK inhibitory activity, most of them exhibited stronger activities than that of genistein, a positive reference compound. Several halophenols also displayed moderate VSMC proliferation inhibitory activity, compound 8c showed higher activity than that of tetrandrine, a positive reference compound. The preliminary structure-activity relationships of these compounds were investigated and discussed. The results provided a foundation for the action mechanism study and further structure optimization of the halophenols. PMID:22946534

  2. ASSAY FOR FLUORESCEIN DIACETATE HYDROLYTIC ACTIVITY: OPTIMIZATION FOR SOIL SAMPLES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the increased interest in integrated soil bioecosystem studies, there has been a need to have a method of measuring overall microbial activity potential. Hydrolysis of fluorescein diacetate (3',6'-diacetylfluorescein [FDA]) has been suggested as a possible method because the ubiquitous lipase, ...

  3. Preparing for NASA's Soil Moisture Active Passive (SMAP) mission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil Moisture Active/Passive (SMAP) Mission is one of the first satellites being developed by NASA in response to the National Research Council’s Decadal Survey. SMAP will make global measurements of the moisture present at Earth's land surface and will distinguish frozen from thawed land surfaces. ...

  4. Aminocyclopyrachlor sorption in biochar and activated charcoal amended soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aminocyclopyrachlor is a new herbicide active ingredient, classified as a member of the new chemical class “pyrimidine carboxylic acids”. It is used for control of broadleaf weeds and brush on non-cropland. Due to its potential mobility in some soils, there is interest in whether aminocyclopyrachlor...

  5. The soil moisture active passive (SMAP) mission and validation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Soil Moisture Active Passive (SMAP) satellite will be launched by the National Aeronautics and Space Administration in October 2014. This satellite is the culmination of basic research and applications development over the past thirty years. During most of this period, research and development o...

  6. Plant Leaf Residue Decomposition, Nutrient Release and Soil Enzyme Activity

    Microsoft Academic Search

    Julia Dux; Lindsey Norgrove; Stefan Hauser; Barbara Wick; Ronald Kühne

    We studied the impact of plant leaf residue decompo sition and nutrient release of nitrogen and phosphorus of two weed species - Imperata cylindrica and Chromolaena odorata - and one native forest species - Phyllanthus discoideus - on soil enzyme activities in a pot experiment in the humid tropics of central Cameroon. We tested th e impact of plant leaf

  7. Overview of the NASA soil moisture active/passive mission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The NASA Soil Moisture Active Passive (SMAP) Mission is currently in design Phase C and scheduled for launch in October 2014. Its mission concept is based on combined L-band radar and radiometry measurements obtained from a shared, rotating 6-meter antennae. These measurements will be used to retrie...

  8. Effects of heat-activated persulfate oxidation on soil microorganisms.

    PubMed

    Tsitonaki, Aikaterini; Smets, Barth F; Bjerg, Poul L

    2008-02-01

    The effects of heat-activated persulfate on indigenous microorganisms and microcosms augmented with Pseudomonas putida KT2440 were studied in laboratory batch reactors with aquifer material. Microscopic enumeration was used to measure the changes in cell density, and acetate consumption was used to evaluate metabolic activity after exposure to activated persulfate. The cell enumerations showed that persulfate concentrations up to 10 g/L did not affect the indigenous microorganisms but were detrimental to P. putida survival. Acetate consumption was inhibited at the highest persulfate dose (10 g/L). The results emphasize the necessity of using multiple toxicity assays and indigenous cultures in order to realistically assess the potential effects of in situ chemical oxidation on soil microorganisms. A comparison to other studies suggests that the effects of activated persulfate on soil microorganisms are less damaging than those of Fenton's reagent and hydrogen peroxide. PMID:17942135

  9. Microbial activity during composting of anthracene-contaminated soil

    Microsoft Academic Search

    Y Ma; J. Y Zhang; M. H Wong

    2003-01-01

    Microbial activity of an anthracene-spiked soil mixed with kitchen waste during laboratory composting at 56–59 °C was studied using an in-vessel technology. The effect of old compost containing acclimated microorganisms on the composting efficiency was also investigated. Microbial succession, microbial enzyme activity, microbial diversity and anthracene removal rate were analyzed during 42 days of composting. The results demonstrated that inoculating

  10. Feeding activity of the earthworm Eisenia andrei in artificial soil

    Microsoft Academic Search

    Tjalling Jager; Roel H. L. J. Fleuren; Willem Roelofs; Arthur C. de Groot

    2003-01-01

    Quantitative information on the feeding activity of earthworms is scarce but this information is valuable in many eco(toxico)logical studies. In this study, the feeding activity of the compost worm Eisenia andrei is examined in artificial soil (OECD medium), with and without a high-quality food source (cow manure), and at two temperatures (10 and 20°C). Methods are provided to estimate the

  11. Actively Heated Fiber Optic Method for Distributed Soil Moisture Monitoring

    NASA Astrophysics Data System (ADS)

    Sayde, C.; Selker, J. S.; Rodriguez-Sinobas, L.; Gil-Rodriguez, M.; Cuenca, R. H.; Tyler, S. W.; English, M.

    2010-12-01

    The temporal and spatial distribution of soil water at scales from 1 to 10,000m is both poorly understood and critical to terrestrial processes. Areas of great uncertainty include the spatio-temporal patterns of: soil water; evapo-transpiration; recharge during and following rainfalls. Observation of dynamics at these scales requires an innovative measurement approach. A novel in-situ distributed measurement of soil water content using temperature measured with Raman scattering in fiber optic cables is presented. This technology, called “Actively Heated Fiber Optic Method,” demonstrated in the lab setting by Sayde et al. 2010 in Water Resources Research involves use of a heat pulse method with fiber optic temperature sensing to obtain precise, distributed measurements of soil water content, with high temporal resolution and sub-meter scale spatial resolution, along a fiber optic cable that can exceed several km in length. The method is based on the influence of water content on soil thermal properties as observed with a buried fiber optical cable monitored by a laser Raman backscatter DTS system. The buried fiber optic is actively heated via electrical resistance, using the steel elements that surround the fiber, and the optical fiber is used as a sub-meter scale thermal sensor to monitor the changes in soil thermal responses every meter along the fiber optic cable. A response metric that has not been previously employed “the time integral of temperature deviation” is used as a simple interpretation of heat data that takes advantage of the characteristics of fiber optic measurements. Validation of the method based on large-column laboratory tests, and field testing results using and 750 m of fiber optic cable buried at 30, 60, and 90 cm depth in the field are presented. The results indicate the feasibility of using the actively heated fiber optic method to monitor soil water content at temporal resolution well under one hour and spatial resolution of 1 m. In principle, this DTS method could monitor soil moisture along cables exceeding 10,000 m in extent. Such measurements could be transformative in our understanding of soil hydrology in natural and managed systems at field and watershed scales.

  12. Degradation kinetics of forchlorfenuron in typical grapevine soils of India and its influence on specific soil enzyme activities

    Microsoft Academic Search

    Kaushik Banerjee; Soma Dasgupta; Dasharath P. Oulkar; Sangram H. Patil; Pandurang G. Adsule

    2008-01-01

    The rate of degradation of forchlorfenuron, a cytokinin-based plant growth regulator (PGR) was explored in typical grapevine soils of India with simultaneous evaluation of its effect on biochemical attributes of the test soils in terms of the activities of specific soil microbial enzymes. In all the test soils, namely clay, sandy-loam and silty-clay, the dissipation rate was faster at the

  13. Studies on Speciation of Antimony in Soil Contaminated by Industrial Activity

    Microsoft Academic Search

    Joseph Lintschinger; Bernhard Michalke; Sigurd Schulte-hostede; Peter Schramel

    1998-01-01

    Antimony is a toxic trace element of growing environmental interest due to its increased anthropogenic input into the environment. Very little is known about the chemical and biological behavior of antimony compounds in soils and sediments. Three soil samples with substantially elevated Sb concentrations (area contaminated by extensive industrial use of Sb compounds), and a soil standard reference material have

  14. Biological permeable reactive barriers coupled with electrokinetic soil flushing for the treatment of diesel-polluted clay soil.

    PubMed

    Mena, Esperanza; Ruiz, Clara; Villaseńor, José; Rodrigo, Manuel A; Cańizares, Pablo

    2015-02-11

    Removal of diesel from spiked kaolin has been studied in the laboratory using coupled electrokinetic soil flushing (EKSF) and bioremediation through an innovative biological permeable reactive barriers (Bio-PRBs) positioned between electrode wells. The results show that this technology is efficient in the removal of pollutants and allows the soil to maintain the appropriate conditions for microorganism growth in terms of pH, temperature, and nutrients. At the same time, EKSF was demonstrated to be a very interesting technology for transporting pollutants, microorganisms and nutrients, although results indicate that careful management is necessary to avoid the depletion of nutrients, which are effectively transported by electro-migration. After two weeks of operation, 30% of pollutants are removed and energy consumption is under 70 kWh m(-3). Main fluxes (electroosmosis and evaporation) and changes in the most relevant parameters (nutrients, diesel, microorganisms, surfactants, moisture conductivity and pH) during treatment and in a complete post-study analysis are studied to give a comprehensive description of the most relevant processes occurring in the soil (pollutant transport and biodegradation). PMID:25262485

  15. Demographic, Biologic, and Other Variables Affecting Monoamine Oxidase Activity

    Microsoft Academic Search

    Donald S. Robinson; Alexander Nies

    1980-01-01

    Monoamine oxidase (MAO) activity has been shown to be influenced by a variety of demographic, biologic, and other variables. Human platelet, plasma, and brain enzyme activities correlate with age and are higher in women. Brain catecholamines tend to decrease with age. The acute effects of ethanol on platelet MAO do not appear to be significant, but chronic ethanol ingestion could

  16. Models Role within Active Learning in Biology. A Case Study

    ERIC Educational Resources Information Center

    Pop-Pacurar, Irina; Tirla, Felicia-Doina

    2009-01-01

    In order to integrate ideas and information creatively, to motivate students and activate their thinking, we have used in Biology classes a series of active methods, among which the methods of critical thinking, which had very good results. Still, in the case of some intuitive, abstract, more difficult topics, such as the cell structure,…

  17. Study the Biological Activities of Tribulus Terrestris Extracts

    Microsoft Academic Search

    Ahmed A. Hussain; Abbas A. Mohammed; H. Ibrahim; Amir H. Abbas

    2009-01-01

    In this study the extracts of the Iraqi herb Tribulus terrestris (Al-Hassage or Al-Kutub) was done by using of polar and non polar solvents, then the biological activity of these extractants was studied in three fields, First, the antibacterial activity (in vitro) on gram positive bacteria (Staphylococcus aureus), and gram negative bacteria (E. coli, Proteus vulgaris, Pseudomonas aerugiuosa, and Klebsiella),

  18. Biologically active traditional medicinal herbs from Balochistan, Pakistan

    Microsoft Academic Search

    Mudassir A. Zaidi; Sidney A. Crow

    2005-01-01

    The biological activities of the following four important medicinal plants of Balochistan, Pakistan were checked; Grewia erythraea Schwein f. (Tiliaceae), Hymenocrater sessilifolius Fisch. and C.A. Mey (Lamiaceae), Vincetoxicum stocksii Ali and Khatoon (Asclepiadaceae) and Zygophyllum fabago L. (Zygophyllaceae). The methanolic extracts were fractionated into hexane, ethyl acetate, chloroform, butanol and water. The antifungal and antibacterial activities of these plants were

  19. Smectites versus palagonites in Mars soil: Evidence from simulations of Viking biology labeled release experiments

    NASA Technical Reports Server (NTRS)

    Banin, A.; Margulies, L.

    1983-01-01

    The results of an experimental comparison between palagonites and a smectite (montmorillonite) in the simulation of the Viking Biology Labeled Release (LR) experiment and conclusions regarding their suitability as MarSAMs are reproved. It was found that palagonites do not cause formate decomposition and C-14 release in their natural form or after acidification and thus cannot be a completely satisfactory analog to the Mars soil studied by Viking.

  20. Biotoxicity assessment of pyrene in soil using a battery of biological assays.

    PubMed

    Khan, Muhammad Imran; Cheema, Sardar Alam; Tang, Xianjin; Shen, Chaofeng; Sahi, Shahbaz Talib; Jabbar, Abdul; Park, Joonhong; Chen, Yingxu

    2012-11-01

    A test battery, composed of a range of biological assays, was applied to evaluate the ecological health of soil aged for 69 days and spiked with a range of pyrene levels (1.04, 8.99, 41.5, 72.6, 136, and 399 ?g g(-1) dry soil; Soxhlet-extracted concentrations after 69 days of aging). Chinese cabbage (Brassica rapa), earthworm (Eisenia fetida), and bacteria (Vibrio fischeri) were used as test organisms to represent different trophic levels. Among the acute ecotoxicity bioassays used, the V. fischeri luminescence inhibition assay was the most sensitive indicator of pyrene toxicity. We observed >8 % light inhibition at the lowest concentration (1.04 ?g g(-1)) pyrene, and this inhibition increased to 60 % at 72.6 ?g g(-1). The sensitivity ranking for toxicity of the pyrene-contaminated soil in the present study was in the following decreasing order: root elongation of Chinese cabbage < earthworm mortality (14 days) < earthworm mortality (28 days) < luminescence inhibition (15 min) < luminescence inhibition (5 min). In addition, genotoxic effects of pyrene were also evaluated by using comet assay in E. fetida. The strong relationship between DNA damage and soil pyrene levels showed that comet assay is suitable for testing the genotoxicity of pyrene-polluted soil. In addition, tail moment was well correlated with soil pyrene levels (r (2) = 0.99). Thus, tail moment may be the most informative DNA-damage parameter representing the results of comet assay. Based on these results, the earthworm DNA damage assay and Microtox test are rapid and sensitive bioassays and can be used to assess the risk of soil with low to high levels of hydrocarbon pollution. Furthermore, an analysis of the toxic effects at several trophic levels is essential for a more comprehensive understanding of the damage caused by highly contaminated soil. PMID:22941450

  1. The validation of forensic DNA extraction systems to utilize soil contaminated biological evidence.

    PubMed

    Kasu, Mohaimin; Shires, Karen

    2015-07-01

    The production of full DNA profiles from biological evidence found in soil has a high failure rate due largely to the inhibitory substance humic acid (HA). Abundant in various natural soils, HA co-extracts with DNA during extraction and inhibits DNA profiling by binding to the molecular components of the genotyping assay. To successfully utilize traces of soil contaminated evidence, such as that found at many murder and rape crime scenes in South Africa, a reliable HA removal extraction system would often be selected based on previous validation studies. However, for many standard forensic DNA extraction systems, peer-reviewed publications detailing the efficacy on soil evidence is either lacking or is incomplete. Consequently, these sample types are often not collected or fail to yield suitable DNA material due to the use of unsuitable methodology. The aim of this study was to validate the common forensic DNA collection and extraction systems used in South Africa, namely DNA IQ, FTA elute and Nucleosave for processing blood and saliva contaminated with HA. A forensic appropriate volume of biological evidence was spiked with HA (0, 0.5, 1.5 and 2.5mg/ml) and processed through each extraction protocol for the evaluation of HA removal using QPCR and STR-genotyping. The DNA IQ magnetic bead system effectively removed HA from highly contaminated blood and saliva, and generated consistently acceptable STR profiles from both artificially spiked samples and crude soil samples. This system is highly recommended for use on soil-contaminated evidence over the cellulose card-based systems currently being preferentially used for DNA sample collection. PMID:25690910

  2. Local knowledge and perception of biological soil crusts by land users in the Sahel (Niger)

    NASA Astrophysics Data System (ADS)

    J-M Ambouta, K.; Hassan Souley, B.; Malam Issa, O.; Rajot, J. L.; Mohamadou, A.

    2012-04-01

    Local knowledge, i.e. knowledge based on accumulation of observations is of great interest for many scientific fields as it can help for identification, evaluation and selection of relevant indicators and furthermore for progress through conservation goals. This study aimed at gathering and understanding the local knowledge and perception of biological soil crusts (BSC) by users of land, pastoralists that cross the Sahel and sedentary farmers. The methodological approach is based on a semi-direct surveys conducted on a north-south rainfall gradient (350 to 650 mm/year) including agricultural- and pastoral-dominated areas in western Niger. Denomination, formation processes, occurrence, distribution and role of biological soil crusts are among the major issues of the inquiry. The results of the surveys showed that BSC are mainly identified by the names of "Bankwado" and "Korobanda", respectively in hausa and zarma langages, what means "toad back". Other denominations varying according to region, ethnic groups and users are used. They are all related to the aspects, colors and behaviour of BSC with regard wetting and drying cycle. From the point of view of users depressed areas and land lied fallow are favourable places for the occurrence of BSC, while cultivation and observed changes in rainfall regimes represent negative factors. The formation processes of BSC are mainly related to the occurrence and the impact of rain and wind on soil surface. Their roles in protecting soil against degradation or as an indicator of soil fertility were recognised by at least 83% of farmers and breeders. This study reveals significant aspects of BSC already validated by scientific knowledge. Integrating the two forms of knowledge will help to define relevant indicators of soil surface dynamics and to perform practices to minimize farming and grazing impacts on BSCs.

  3. New azidometalkojates and their biological activity

    Microsoft Academic Search

    D. Hudecová; S. Jantová; M. Melník; M. Uher

    1996-01-01

    Azidometalkojates of the general formula MX2 (M=Cu, Mn, Mg, Zn or Ni and X=5-hydroxy-2-azidomethyl-4H-pyran-4-one) were prepared and tested for antibacterial, antifungal and cytotoxic effects. The mangan and zinc derivatives\\u000a are not active against any the tested microorganisms. A weak antibacterial activity was found with the copper derivative.\\u000a The strongest antifungal effects were shown by the nickel derivative while the highest

  4. Novel oxindole derivatives and their biological activity.

    PubMed

    Strigácová, J; Hudecová, D; Mikulásová, M; Varecka, L; Lásiková, A; Végh, D

    2001-01-01

    The antifungal activity of fourteen novel derivatives of oxindole with side chain was studied using representatives of toxinogenic, phytopathogenic and dermatophytic filamentous fungi. Derivatives with exocyclic C=C bond in position C-3 exhibited a higher antifungal activity compared with derivatives with an exocyclic C-C bond in the same position. The strongest antifungal effects were shown by 3-(-2-thienoylmethylidene)-indol-2(3H)-ones. PMID:11702401

  5. Synthesis and biological activities of 8-arylflavones

    Microsoft Academic Search

    Tran Thanh Dao; Soo Bae Kim; Kwan-Seog Sin; Sanghee Kim; Hyun Pyo Kim

    2004-01-01

    A number of 8-arylflavones have been synthesized as congeners of wogonin and evaluated for their inhibitory activities of\\u000a PGE2 production. 8-Arylflavones were obtained from commercially available chrysin via two different synthetic pathways. Most 8-arylflavones\\u000a exhibited much reduced inhibitory activities against COX-2 catalyzed PGE2 production compared to that of wogonin. Functional group replacement at the 8-position of wogonin from methoxy to

  6. [Galanin: a new biologically active gastrointestinal neuropeptide].

    PubMed

    Bauer, F E

    1990-03-01

    The 29 amino acid containing neuropeptide galanin is localized in the intrinsic nervous system of the entire gastrointestinal tract and the pancreas. It was found in man and several animal species. Molecular biology studies revealed different molecular forms of galanin in several mammalian species including man. The galanin precursor was also found. Galanin shows several potent pharmacological actions: it inhibits gastrointestinal motility in man. It also has an inhibitory effect on intestinal smooth muscle contractility of several animal species. These actions are mediated directly by opening of potassium channels and indirectly by inhibition of acetylcholine release. In addition galanin inhibits pancreatic hormone secretion (i.e. hypoinsulinemia, hyperglycemia) and partly the release of hormones localized in the gastrointestinal tract. On exocrine glands in man (salivary glands) galanin has hydrokinetic actions. The physiological role of galanin might be regulation of gastrointestinal motility, control of secretory function of intestine and a regulatory role in endocrine and exocrine gland secretion. PMID:1693024

  7. Microbial metabolic activity in soil as measured by dehydrogenase determinations

    NASA Technical Reports Server (NTRS)

    Casida, L. E., Jr.

    1977-01-01

    The dehydrogenase technique for measuring the metabolic activity of microorganisms in soil was modified to use a 6-h, 37 C incubation with either glucose or yeast extract as the electron-donating substrate. The rate of formazan production remained constant during this time interval, and cellular multiplication apparently did not occur. The technique was used to follow changes in the overall metabolic activities of microorganisms in soil undergoing incubation with a limiting concentration of added nutrient. The sequence of events was similar to that obtained by using the Warburg respirometer to measure O2 consumption. However, the major peaks of activity occurred earlier with the respirometer. This possibly is due to the lack of atmospheric CO2 during the O2 consumption measurements.

  8. Photo-activated biological processes as quantum measurements

    E-print Network

    Atac Imamoglu; K. Birgitta Whaley

    2014-08-21

    We outline a framework for describing photo-activated biological reactions as generalized quantum measurements of external fields, for which the biological system takes on the role of a quantum meter. By using general arguments regarding the Hamiltonian that describes the measurement interaction, we identify the cases where it is essential for a complex chemical or biological system to exhibit non-equilibrium quantum coherent dynamics in order to achieve the requisite functionality. We illustrate the analysis by considering measurement of the solar radiation field in photosynthesis and measurement of the earth's magnetic field in avian magnetoreception.

  9. Soils Activity Mobility Study: Methodology and Application

    SciTech Connect

    Silvas, Alissa; Yucel, Vefa

    2014-09-29

    This report presents a three-level approach for estimation of sediment transport to provide an assessment of potential erosion risk for sites at the Nevada National Security Site (NNSS) that are posted for radiological purposes and where migration is suspected or known to occur due to storm runoff. Based on the assessed risk, the appropriate level of effort can be determined for analysis of radiological surveys, field experiments to quantify erosion and transport rates, and long-term monitoring. The method is demonstrated at contaminated sites, including Plutonium Valley, Shasta, Smoky, and T-1. The Pacific Southwest Interagency Committee (PSIAC) procedure is selected as the Level 1 analysis tool. The PSIAC method provides an estimation of the total annual sediment yield based on factors derived from the climatic and physical characteristics of a watershed. If the results indicate low risk, then further analysis is not warranted. If the Level 1 analysis indicates high risk or is deemed uncertain, a Level 2 analysis using the Modified Universal Soil Loss Equation (MUSLE) is proposed. In addition, if a sediment yield for a storm event rather than an annual sediment yield is needed, then the proposed Level 2 analysis should be performed. MUSLE only provides sheet and rill erosion estimates. The U.S. Army Corps of Engineers Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) provides storm peak runoff rate and storm volumes, the inputs necessary for MUSLE. Channel Sediment Transport (CHAN-SED) I and II models are proposed for estimating sediment deposition or erosion in a channel reach from a storm event. These models require storm hydrograph associated sediment concentration and bed load particle size distribution data. When the Level 2 analysis indicates high risk for sediment yield and associated contaminant migration or when there is high uncertainty in the Level 2 results, the sites can be further evaluated with a Level 3 analysis using more complex and labor- and data-intensive methods. For the watersheds analyzed in this report using the Level 1 PSIAC method, the risk of erosion is low. The field reconnaissance surveys of these watersheds confirm the conclusion that the sediment yield of undisturbed areas at the NNSS would be low. The climate, geology, soils, ground cover, land use, and runoff potential are similar among these watersheds. There are no well-defined ephemeral channels except at the Smoky and Plutonium Valley sites. Topography seems to have the strongest influence on sediment yields, as sediment yields are higher on the steeper hill slopes. Lack of measured sediment yield data at the NNSS does not allow for a direct evaluation of the yield estimates by the PSIAC method. Level 2 MUSLE estimates in all the analyzed watersheds except Shasta are a small percentage of the estimates from PSIAC because MUSLE is not inclusive of channel erosion. This indicates that channel erosion dominates the total sediment yield in these watersheds. Annual sediment yields for these watersheds are estimated using the CHAN-SEDI and CHAN-SEDII channel sediment transport models. Both transport models give similar results and exceed the estimates obtained from PSIAC and MUSLE. It is recommended that the total watershed sediment yield of watersheds at the NNSS with flow channels be obtained by adding the washload estimate (rill and inter-rill erosion) from MUSLE to that obtained from channel transport models (bed load and suspended sediment). PSIAC will give comparable results if factor scores for channel erosion are revised towards the high erosion level. Application of the Level 3 process-based models to estimate sediment yields at the NNSS cannot be recommended at this time. Increased model complexity alone will not improve the certainty of the sediment yield estimates. Models must be calibrated against measured data before model results are accepted as certain. Because no measurements of sediment yields at the NNSS are available, model validation cannot be performed. This is also true for the models used in the L

  10. Formation of biologically active substances by rhizosphere bacteria and their effect on plant growth

    Microsoft Academic Search

    A. Hussain; V. Van?ura

    1970-01-01

    Nine out of seventeen strains of bacteria with a pronounced effect on seed germination and on seedling growth, isolated from\\u000a root surfaces and rhizosphere soil of maize, were selected for a study on the formation of biologically active substances.\\u000a ?-Indole acetic acid (45–72 ?g\\/1.000 ml) was produced by four strains, gibberelline-like substances (1.0–60.0 ?g\\/1.000ml)\\u000a by all strains, biotin and pantothenic

  11. Novel oxindole derivatives and their biological activity

    Microsoft Academic Search

    J. Strigácová; D. Hudecová; M. Mikulášová; L'. Vare?ka; A. Lásiková; D. Végh

    2001-01-01

    The antifungal activity of fourteen novel derivatives of oxindole with side chain was studied using representatives of toxinogenic,\\u000a phytopathogenic and dermatophytic filamentous fungi. Derivatives with exocyclic C=C bond in position C-3 exhibited a higher\\u000a antifungal activity compared with derivatives with an exocyclic C?C bond in the same position. The strongest antifungal effects\\u000a were shown by 3-(-2-thienoylmethylidene)-indol-2(3H)-ones.

  12. New azidometalkojates and their biological activity.

    PubMed

    Hudecová, D; Jantová, S; Melník, M; Uher, M

    1996-01-01

    Azidometalkojates of the general formula MX2 (M = Cu, Mn, Mg, Zn or Ni and X = 5-hydroxy-2-azidomethyl-4H-pyran-4-one) were prepared and tested for antibacterial, antifungal and cytotoxic effects. The mangan and zinc derivatives are not active against any the tested microorganisms. A weak antibacterial activity was found with the copper derivative. The strongest antifungal effects were shown by the nickel derivative while the highest cytotoxic effect on HeLa cells was manifested by the zinc derivative. PMID:9131802

  13. Synthesis and Biological Activity on Some Organoantimony (III) Compounds

    Microsoft Academic Search

    Ravi Kant; Amresh K. Chandrashekar; Anil K. S. Kumar

    2008-01-01

    Organoantimony (III) amides of the type Ar2SbL; (Ar = C6H5, C6F5, C6H4F; L = succinimide and phthallimide) were synthesized and assayed for their biological activities. These compounds exhibited significant in-vitro antitumor activity against human breast adenocarcinoma cell line (MCF-7), mammary cancer cell line (EVSA-7), and antibacterial activity against human pathogenic bacteria viz. Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiela pneumoniae. These

  14. Biological Activity of a Growth Factor for Ovarian Cells

    PubMed Central

    Jones, Kenneth L.; Gospodarowicz, Denis

    1974-01-01

    The biological activity of a protein growth factor is described. This factor was isolated from bovine pituitary tissue, and its activity was tested on cells of rat ovarian origin. Activity was assayed as growth-promoting potential measured by cell counts and is concentrationdependent. Similar growth stimulation was not produced by several cyclic nucleotides tested, neither was there crossreactivity between this growth factor and a chemically similar one produced by rat liver cells. Images PMID:4372617

  15. TECHNOLOGY EVALUATION REPORT: PILOT-SCALE DEMONSTRATION OF A SLURRY-PHASE BIOLOGICAL REACTOR FOR CREOSOTE-CONTAMINATED SOIL

    EPA Science Inventory

    This report documents a pilot-scale test of a slurry-phase biological reactor for treatment of creosote-contaminated soil. he technology used was a reactor system in which an aqueous slurry of soil was mixed with appropriate nutrients and seeded with microorganisms to enhance the...

  16. Correlates of biological soil crust abundance across a continuum of spatial scales: support for a hierarchical conceptual model

    Microsoft Academic Search

    MATTHEW A. BOWKER; JAYNE BELNAP; DIANE W. DAVIDSON; HARLAND GOLDSTEIN

    2006-01-01

    Summary 1. Desertification negatively impacts a large proportion of the global human popula- tion and > 30% of the terrestrial land surface. Better methods are needed to detect areas that are at risk of desertification and to ameliorate desertified areas. Biological soil crusts are an important soil lichen-moss-microbial community that can be used toward these goals, as (i) bioindicators of

  17. Field Trial Assessment of Biological, Chemical, and Physical Responses of Soil to Tillage Intensity, Fertilization, and Grazing

    Microsoft Academic Search

    Silvina Vargas Gil; Analia Becker; Claudio Oddino; Mónica Zuza; Adriana Marinelli; Guillermo March

    2009-01-01

    Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological\\u000a indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in\\u000a response to different management strategies. A long-term field trial was conducted to study the effects of different tillage\\u000a systems (NT: no tillage, DH:

  18. Changes of Soil Enzyme Activities By Simulated Acid and Nitrogen Deposition

    Microsoft Academic Search

    H. Kang; D. Lee

    1998-01-01

    Effects of acid and nitrogen depositions on soil microbial activities were studied in a laboratory-based experiment. Five treatments were added to forest soil for five weeks, and soil enzyme activities were determined along with chemical properties. There was little change in pH and nitrogen availability. Dehydrogenase, phosphatase and arylsulphatase activities were decreased by all the acidic treatments compared to the

  19. Biologically active compounds of semi-metals.

    PubMed

    Rezanka, Tomás; Sigler, Karel

    2008-02-01

    Semi-metals (boron, silicon, arsenic and selenium) form organo-metal compounds, some of which are found in nature and affect the physiology of living organisms. They include, e.g., the boron-containing antibiotics aplasmomycin, borophycin, boromycin, and tartrolon or the silicon compounds present in "silicate" bacteria, relatives of the genus Bacillus, which release silicon from aluminosilicates through the secretion of organic acids. Arsenic is incorporated into arsenosugars and arsenobetaines by marine algae and invertebrates, and fungi and bacteria can produce volatile methylated arsenic compounds. Some prokaryotes can use arsenate as a terminal electron acceptor while others can utilize arsenite as an electron donor to generate energy. Selenium is incorporated into selenocysteine that is found in some proteins. Biomethylation of selenide produces methylselenide and dimethylselenide. Selenium analogues of amino acids, antitumor, antibacterial, antifungal, antiviral, anti-infective drugs are often used as analogues of important pharmacological sulfur compounds. Other metalloids, i.e. the rare and toxic tellurium and the radioactive short-lived astatine, have no biological significance. PMID:17991498

  20. Sensitive bioassay for detection of biologically active ricin in food.

    PubMed

    Rasooly, Reuven; He, Xiaohua

    2012-05-01

    The potential use of ricin as an agent of biological warfare highlights the need to develop fast and effective methods to detect biologically active ricin. The current "gold standard" for ricin detection is an in vivo mouse bioassay; however, this method is not practical to test on a large number of samples and raises ethical concerns with regard to the use of experimental animals. In this work, we generated adenoviral vectors that express the green fluorescent protein gene and used the relative fluorescence units intensity inhibition by transduced cells for quantitative measurement of biologically active ricin. The detection limit of the assay was 200 pg/ml, which is over 500,000 times greater than the adult human lethal oral dose. The inhibition of fluorescence intensity between ricin treatment and control was higher in 72-h posttransduction Vero cells than 24-h human embryonic kidney cells. Therefore, to detect biologically active ricin in food matrices that might influence the assay, we used 72-h posttransduction Vero cells. This simple assay could be used for large-scale screening to detect biologically active ricin in food without added substrates or use of cell fixation methods. PMID:22564946

  1. Changes in soil respiration after thinning activities in dense Aleppo pine forests

    NASA Astrophysics Data System (ADS)

    Llovet, Joan; Alonso, Maciŕ; Cerdŕ, Artemi

    2015-04-01

    Forest fires are a widespread perturbation in Mediterranean areas, and they have tended to increase during the last decades (Pausas, 2004; Moreno et al, 1998). Aleppo pine (Pinus halepensis Mill) is dominant specie in some forest landscapes of western Mediterranean Basin, due to its capacity to colonize abandoned fields, and also due to afforestation practices mainly performed during the 20th century (Ruiz Navarro et al., 2009). Aleppo pine tends to die as consequence of forest fires, although it is able to disperse a high quantity of seeds which easily germinates. These dispersion and germination can result in dense forests with high inter and intra-specific competition, low diversity, low growth, and high fuel accumulation, increasing the risk of new forest fires. These forests of high density present ecological problems and management difficulties that require preventive treatments. Thinning treatments are common in these types of communities, but the management has to be oriented towards strengthening their functions. In the context of global change, better understandings of the implications of forest management practices in the carbon cycle are necessary. The objective of this study was to examine the evolution of seasonal soil respiration after treatment of selective thinning in dense Aleppo pine forests. The study area covers three localities placed in the Valencian Community (E Spain) affected by a forest fire in 1994. Thinning activities were done 16 years after the fire, reducing pine density from around 100,000 individuals per hectare to around 900 individuals per hectare. Soil respiration was measured in situ with a portable soil respiration instrument (LI-6400, LiCor, Lincoln, NB, USA) fitted with a soil respiration chamber (6400-09, LiCor, Lincoln, NB, USA). We installed 12 plots per treatment (control and thinned) and locality, being a total of 72 plots. We carried out 13 measurements covering a period of one year. We also estimated other related variables (i.e. soil characteristics, potential soil heterotrophic respiration, plant biomass surrounding each plot, soil temperature, and soil moisture). Main results showed a seasonal variation of soil respiration as related by other authors (i.e. Almagro et al., 2009), being soil respiration restricted by drying during summer, and by low temperatures during winter. On the other hand, thinning significantly diminished soil respiration, its decrease was around 33% (from 5.3 micromole CO2 m-2 second-1, to 3.6 micromole CO2 m-2 second-1). Our results suggest that autotrophic respiration could be highly responsible of this decrease: we found significant and positive relationships between soil respiration and vegetation surrounding plots, and we did not find differences in potential soil heterotrophic respiration between treatments. Acknowledgements We thanks the financial support of the RESILIEN project funded by the Spanish Government, Ministerio de Ciencia e Innovación CGL2011-30515-C02-02. The RECARE project is funded by the European Commission FP7 program, ENV.2013.6.2-4 "Sustainable land care in Europe". References Almagro, M., López, J., Querejeta, J. I., Martínez Mena, M. 2009. Temperature dependence of soil CO2 efflux is strongly modulated by seasonal patterns of moisture availability in a Meditarranean ecosystem. Soil Biology and Biochemistry, 41. 594-605 Moreno, J.M., Vázquez, A., Vélez, R. 1998. Recent history of forest fires in Spain. In: Moreno, J. M. (ed). Large Fires. Backhuys Publishers, Leiden, The Netherlands, pp. 159-185. Pausas, J. G., Ribeiro, E., Vallejo, V. R. 2004. Post-fire regeneration variability of Pinus halepensis in the eastern Iberian Peninsula. Forest Ecology and Management, 203. 251-259. Ruiz Navarro, A., Barberá, G. G., Navarro Cano, J. A., Albaladejo, J., Castillo, V. M. 2009. Soil dynamics in Pinus halepensis reforestation: Effect of microenvironment and previous land use. Geoderma, 153. 353-361.

  2. Synthesis and biological activity of 8-arylergolines.

    PubMed

    Bach, N J; Kornfeld, E C; Dorman, D E

    1977-08-01

    9,10-Didehydro-6-methyl-8beta-arylergolines 2, in which the carboxyl group of lysergic acid and isolysergic acid is replaced by various aryl groups, were prepared in two steps by alkylation of aromatic substrates with the tetracyclic allylic alcohol 3, followed by aromatization with MnO2. The new ergolines 2 have modest prolactin-inhibiting and rat antimuricidal activities and possess significant alpha-blocking and antiserotonin properties. PMID:561190

  3. Glucosinolates – biochemistry, genetics and biological activity

    Microsoft Academic Search

    Richard Mithen

    2001-01-01

    This paper provides a brief overview of the biochemistry, genetics andbiological activity of glucosinolates and their degradation products.These compounds are found in vegetative and reproductive tissues of16 plant families, but are most well known as the major secondarymetabolites in the Brassicaceae. Following tissue disruption, theyare hydrolysed to a variety of products of which isothiocyanates(`mustard oils') are the most prominent. The

  4. Biologically active withanolides from Withania coagulans.

    PubMed

    Ihsan-ul-Haq; Youn, Ui Joung; Chai, Xingyun; Park, Eun-Jung; Kondratyuk, Tamara P; Simmons, Charles J; Borris, Robert P; Mirza, Bushra; Pezzuto, John M; Chang, Leng Chee

    2013-01-25

    Bioassay-directed isolation and purification of the crude extract of Withania coagulans, using two assays for cancer chemopreventive mechanisms, led to the isolation of three new steroidal lactones, withacoagulin G (1), withacoagulin H (2), and withacoagulin I (3), along with six known derivatives (4-9). The structures and absolute stereochemistry of these compounds were determined on the basis of spectroscopic analyses, including 1D and 2D NMR, mass spectrometry, and CD analyses. The structure of 1 was confirmed using X-ray diffraction methods. Compounds 1-9 inhibited nitric oxide production in lipopolysaccharide-activated murine macrophage RAW 264.7 cells with IC(50) values in the range of 1.9-38.2 ?M. Compounds 1 and 2 were the most active (IC(50) 3.1 and 1.9 ?M, respectively). Withanolides 1-9 exhibited inhibition of tumor necrosis factor-? (TNF-?)-induced nuclear factor-kappa B (NF-?B) activation with IC(50) values in the range of 1.60-12.4 ?M. PMID:23316950

  5. Biologically active constituents of Aglaia erythrosperma.

    PubMed

    Phongmaykin, Jarinporn; Kumamoto, Takuya; Ishikawa, Tsutomu; Saifah, Ekarin; Suttisri, Rutt

    2011-10-01

    From the fruits and leaves of Aglaia erythrosperma (Meliaceae), 10 chemical constituents were isolated and identified, i.e. the dammarane triterpenoids cabraleadiol (1), cabraleahydroxylactone (2), ethyl eichlerianoate (3), eichlerialactone (4), aglinin A (5), cabralealactone (6), the aglaialactone 5,6-desmethylenedioxy-5-methoxy-aglalactone (7), the flavagline 4'-demethoxy-3',4'-methylenedioxy-methyl rocaglate (8) and two coumarins: scoparone and scopoletin. Flavagline 8 exhibited antimalarial activity with an IC(50) value of 7.30 µg mL(-1) and was strongly cytotoxic against small cell lung cancer (NCI-H187), epidermoid carcinoma (KB) and breast cancer (BC) cell lines, with IC(50) values of 2.17, 2.10 and 0.11 µg mL(-1), respectively. Aglinin A (5) displayed moderate cytotoxicity against all the three cancer cell lines, whereas ethyl eichlerianoate (3), cabralealactone (6) and the aglaialactone 7 were exclusively cytotoxic to NCI-H187 cell line. Cabraleahydroxylactone (2) showed antiviral activity against herpes simplex virus type-1 with an IC(50) value of 3.20 µg mL(-1), in comparison with the standard acyclovir (IC(50)?= 1.90 µg mL(-1)). When tested for antimycobacterial activity against Mycobacterium tuberculosis H(37)Ra, compounds 1-4 and 6-8 displayed minimum inhibitory concentration in the range of 25-50 µg mL(-1). PMID:22011221

  6. Biological Activity of Aminophosphonic Acids and Their Short Peptides

    NASA Astrophysics Data System (ADS)

    Lejczak, Barbara; Kafarski, Pawel

    The biological activity and natural occurrence of the aminophosphonic acids were described half a century ago. Since then the chemistry and biology of this class of compounds have developed into the separate field of phosphorus chemistry. Today it is well acknowledged that these compounds possess a wide variety of promising, and in some cases commercially useful, physiological activities. Thus, they have found applications ranging from agrochemical (with the herbicides glyphosate and bialaphos being the most prominent examples) to medicinal (with the potent antihypertensive fosinopril and antiosteoporetic bisphosphonates being examples).

  7. [Biological activity of Penicillium sp. 10-51 exometabolites].

    PubMed

    Savchuk, Ia I; Za?chenko, A M; Tsyganenko, E S

    2012-01-01

    Silica gel column chromatography (silica gel "L" II kind of activity 100/160 mkm) of the chloroform extract from the cultural filtrate of Penicillium sp. 10-51 gave two fractions (chloroform and chloroform-acetone, 5:1) having biological activity. Recrystallization yielded two compounds. On the basis of physico-chemical and spectral data these compounds were identified as curvularin and hydroxycurvularin, which have a large spectrum of biological action as to bacteria, yeast, blue-green algae and phytopathogenic micromycetes. PMID:23088100

  8. The biological activity of structurally defined inositol glycans

    PubMed Central

    Goel, Meenakshi; Azev, Viatcheslav N; d’Alarcao, Marc

    2009-01-01

    Background The inositol glycans (IGs) are glycolipid-derived carbohydrates produced by insulin-sensitive cells in response to insulin treatment. IGs exhibit an array of insulin-like activities including stimulation of lipogenesis, glucose transport and glycogen synthesis, suggesting that they may be involved in insulin signal transduction. However, because the natural IGs are structurally heterogeneous and difficult to purify to homogeneity, an understanding of the relationship between structure and biological activity has relied principally on synthetic IGs of defined structure. Discussion This article briefly describes what is known about the role of IGs in signal transduction and reviews the specific biological activities of the structurally defined IGs synthesized and tested to date. Conclusion A pharmacophore for IG activity begins to emerge from the reviewed data and the structural elements necessary for activity are summarized. PMID:20390053

  9. An Inquiry Laboratory Activity for Biology

    NSDL National Science Digital Library

    Nancy Contolini (Brookfield High School REV)

    1994-07-30

    The "cookbook " style approach to studying biochemical reactions mediated by enzymes is changed to an inquiry approach. Cooperative teams are each given two questions about the types of living materials that contain the enzymes that break down hydrogen peroxide, and under what conditions the enzyme works best. They write hypotheses and design and conduct experiments to test these hypotheses. The activity provides students the opportunity to engage in meaningful scientific inquiry because they must truly understand the problem in order to attempt to solve it, to construct meaning in performing experiments, to practice observational skills, and to communicate in writing and in reporting orally to the class on their group results.

  10. Biologically-Active Gold(III) Complexes

    PubMed Central

    Parish, R. V.

    1999-01-01

    A review is given of the background to and results of the succesful pharmacological testing of [AuX2(damp)] (X = Cl, OAc; damp = 2?Me2 NCH2C6 H4) against a range of microbes, fungi and tumouts, culminating in in vivo xenografts of ZR-1-75. These are the first fully evaluated gold(III) complexes. The activity and reactions of the diacetato-complex bear a resemblance to cisplatin, and some of the relevant chemistry is discussed. Preliminary screening data for C,P-chelated tertiary phosphine derivatives of gold(III) are presented. PMID:18475902

  11. Examination of the Active Fraction of Soil Bacterial Community and Rain Pulses

    E-print Network

    Vallino, Joseph J.

    often results in a pulse of soil respiration, known as a rain pulse. Soil microbial communities, measuring respiration rates and subsampling the soil for microbial analysis 4 times during a 24-hour period abundance and the active portion of the bacterial community, respectively. A pulse in soil respiration

  12. Impact of sulfadiazine and chlorotetracycline on soil bacterial community structure and respiratory activity

    Microsoft Academic Search

    Yvonne Zielezny; Joost Groeneweg; Harry Vereecken; Wolfgang Tappe

    2006-01-01

    Veterinary medicines enter agricultural soils by the use of animal excrements as fertilizers. To study their impact on soil bacterial communities, microcosms containing orthic luvisol soil were spiked with the antimicrobial agents sulfadiazine (SDZ) and chlorotetracycline (CTC) at three different concentrations (1, 10, 50mgkg?1 soil) and incubated for 48 days at 20°C. The impact on the microbial respiratory activity was

  13. Ageing effects of casts of Aporrectodea caliginosa on soil microbial community structure and activity

    Microsoft Academic Search

    Manuel Aira; Cristina Lazcano; María Gómez-Brandón; Jorge Domínguez

    2010-01-01

    We studied the ageing of casts of the earthworm species Aporrectodea caliginosa in the field and their effects on soil microbial community structure and activity in a grassland soil. For this purpose, we sampled casts and the bulk soil (below and surrounding casts), 1 and 2 months after deposition of the casts. Discriminant and cluster analyses separated casts from soil

  14. Effects of long term irrigation with polluted water and sludge amendment on some soil enzyme activities

    Microsoft Academic Search

    F. O. Topac; H. S. Baskaya; U. Alkan; A. V. Katkat

    2008-01-01

    The objective of this study was to determine the effects of wastewater sludge-fly ash mixtures on urease, dehydrogenase, alkaline phosphatase and beta-glucosidase activities in soils. In order to evaluate the probable effects of previous soil management practices (irrigation with polluted water) on soil enzymes, two different soil samples which were similar in physical properties, but different in irrigation practice were

  15. Teaching Systems Biology: An Active-learning Approach

    PubMed Central

    2005-01-01

    With genomics well established in modern molecular biology, recent studies have sought to further the discipline by integrating complementary methodologies into a holistic depiction of the molecular mechanisms underpinning cell function. This genomic subdiscipline, loosely termed “systems biology,” presents the biology educator with both opportunities and obstacles: The benefit of exposing students to this cutting-edge scientific methodology is manifest, yet how does one convey the breadth and advantage of systems biology while still engaging the student? Here, I describe an active-learning approach to the presentation of systems biology. In graduate classes at the University of Michigan, Ann Arbor, I divided students into small groups and asked each group to interpret a sample data set (e.g., microarray data, two-hybrid data, homology-search results) describing a hypothetical signaling pathway. Mimicking realistic experimental results, each data set revealed a portion of this pathway; however, students were only able to reconstruct the full pathway by integrating all data sets, thereby exemplifying the utility in a systems biology approach. Student response to this cooperative exercise was extremely positive. In total, this approach provides an effective introduction to systems biology appropriate for students at both the undergraduate and graduate levels. PMID:16341259

  16. Heterotrophic Microbes, Microbial and Enzymatic Activity in Antarctic Soils

    Microsoft Academic Search

    M. Bölter; E. Kandeler; S. J. Pietr; R. D. Seppelt

    \\u000a Defining the soil microbial community or its activity is often like a fight against Servante's windmills. Despite the many\\u000a methods which are available for describing individual figures of this 'black box', many uncertainties remain in this important\\u000a ecological compartment. Today's methodologies still do not allow us to obtain the full picture of the microbial world. The\\u000a approach to understanding the

  17. Gemini ester quat surfactants and their biological activity.

    PubMed

    ?uczy?ski, Jacek; Fr?ckowiak, Renata; W?och, Aleksandra; Kleszczy?ska, Halina; Witek, Stanis?aw

    2013-03-01

    Cationic gemini surfactants are an important class of surface-active compounds that exhibit much higher surface activity than their monomeric counterparts. This type of compound architecture lends itself to the compound being easily adsorbed at interfaces and interacting with the cellular membranes of microorganisms. Conventional cationic surfactants have high chemical stability but poor chemical and biological degradability. One of the main approaches to the design of readily biodegradable and environmentally friendly surfactants involves inserting a bond with limited stability into the surfactant molecule to give a cleavable surfactant. The best-known example of such a compound is the family of ester quats, which are cationic surfactants with a labile ester bond inserted into the molecule. As part of this study, a series of gemini ester quat surfactants were synthesized and assayed for their biological activity. Their hemolytic activity and changes in the fluidity and packing order of the lipid polar heads were used as the measures of their biological activity. A clear correlation between the hemolytic activity of the tested compounds and their alkyl chain length was established. It was found that the compounds with a long hydrocarbon chain showed higher activity. Moreover, the compounds with greater spacing between their alkyl chains were more active. This proves that they incorporate more easily into the lipid bilayer of the erythrocyte membrane and affect its properties to a greater extent. A better understanding of the process of cell lysis by surfactants and of their biological activity may assist in developing surfactants with enhanced selectivity and in widening their range of application. PMID:23271433

  18. Mineral exploration and soil analysis using in situ neutron activation

    USGS Publications Warehouse

    Senftle, F.E.; Hoyte, A.F.

    1966-01-01

    A feasibility study has been made to operate by remote control an unshielded portable positive-ion accelerator type neutron source to induce activities in the ground or rock by "in situ" neutron irradiation. Selective activation techniques make it possible to detect some thirty or more elements by irradiating the ground for periods of a few minutes with either 3-MeV or 14-MeV neutrons. The depth of penetration of neutrons, the effect of water content of the soil on neutron moderation, gamma ray attenuation in the soil and other problems are considered. The analysis shows that, when exploring for most elements of economic interest, the reaction 2H(d,n)3He yielding ??? 3-MeV neutrons is most practical to produce a relatively uniform flux of neutrons of less than 1 keV to a depth of 19???-20???. Irradiation with high energy neutrons (??? 14 MeV) can also be used and may be better suited for certain problems. However, due to higher background and lower sensitivity for the heavy minerals, it is not a recommended neutron source for general exploration use. Preliminary experiments have been made which indicate that neutron activation in situ is feasible for a mineral exploration or qualititative soil analysis. ?? 1976.

  19. Effects of altered temperature and precipitation on desert protozoa associated with biological soil crusts

    USGS Publications Warehouse

    Darby, B.J.; Housman, D.C.; Zaki, A.M.; Shamout, Y.; Adl, S.M.; Belnap, J.; Neher, D.A.

    2006-01-01

    Biological soil crusts are diverse assemblages of bacteria, cyanobacteria, algae, fungi, lichens, and mosses that cover much of arid land soils. The objective of this study was to quantify protozoa associated with biological soil crusts and test the response of protozoa to increased temperature and precipitation as is predicted by some global climate models. Protozoa were more abundant when associated with cyanobacteria/lichen crusts than with cyanobacteria crusts alone. Amoebae, flagellates, and ciliates originating from the Colorado Plateau desert (cool desert, primarily winter precipitation) declined 50-, 10-, and 100-fold, respectively, when moved in field mesocosms to the Chihuahuan Desert (hot desert, primarily summer rain). However, this was not observed in protozoa collected from the Chihuahuan Desert and moved to the Sonoran desert (hot desert, also summer rain, but warmer than Chihuahuan Desert). Protozoa in culture began to encyst at 37??C. Cysts survived the upper end of daily temperatures (37-55??C), and could be stimulated to excyst if temperatures were reduced to 15??C or lower. Results from this study suggest that cool desert protozoa are influenced negatively by increased summer precipitation during excessive summer temperatures, and that desert protozoa may be adapted to a specific desert's temperature and precipitation regime. ?? 2006 by the International Society of Protistologists.

  20. Common and distinguishing features of the bacterial and fungal communities in biological soil crusts and shrub root zone soils

    USGS Publications Warehouse

    Steven, Blaire; Gallegos-Graves, La Verne; Yeager, Chris; Belnap, Jayne; Kuske, Cheryl R.

    2013-01-01

    Soil microbial communities in dryland ecosystems play important roles as root associates of the widely spaced plants and as the dominant members of biological soil crusts (biocrusts) colonizing the plant interspaces. We employed rRNA gene sequencing (bacterial 16S/fungal large subunit) and shotgun metagenomic sequencing to compare the microbial communities inhabiting the root zones of the dominant shrub, Larrea tridentata (creosote bush), and the interspace biocrusts in a Mojave desert shrubland within the Nevada Free Air CO2 Enrichment (FACE) experiment. Most of the numerically abundant bacteria and fungi were present in both the biocrusts and root zones, although the proportional abundance of those members differed significantly between habitats. Biocrust bacteria were predominantly Cyanobacteria while root zones harbored significantly more Actinobacteria and Proteobacteria. Pezizomycetes fungi dominated the biocrusts while Dothideomycetes were highest in root zones. Functional gene abundances in metagenome sequence datasets reflected the taxonomic differences noted in the 16S rRNA datasets. For example, functional categories related to photosynthesis, circadian clock proteins, and heterocyst-associated genes were enriched in the biocrusts, where populations of Cyanobacteria were larger. Genes related to potassium metabolism were also more abundant in the biocrusts, suggesting differences in nutrient cycling between biocrusts and root zones. Finally, ten years of elevated atmospheric CO2 did not result in large shifts in taxonomic composition of the bacterial or fungal communities or the functional gene inventories in the shotgun metagenomes.

  1. Diazotrophic Community Structure and Function in Two Successional Stages of Biological Soil Crusts from the Colorado Plateau and Chihuahuan Desert

    USGS Publications Warehouse

    Yeager, C.M.; Kornosky, J.L.; Housman, D.C.; Grote, E.E.; Belnap, J.; Kuske, C.R.

    2004-01-01

    The objective of this study was to characterize the community structure and activity of N2-fixing microorganisms in mature and poorly developed biological soil crusts from both the Colorado Plateau and Chihuahuan Desert. Nitrogenase activity was approximately 10 and 2.5 times higher in mature crusts than in poorly developed crusts at the Colorado Plateau site and Chihuahuan Desert site, respectively. Analysis of nifH sequences by clone sequencing and the terminal restriction fragment length polymorphism technique indicated that the crust diazotrophic community was 80 to 90% heterocystous cyanobacteria most closely related to Nostoc spp. and that the composition of N2-fixing species did not vary significantly between the poorly developed and mature crusts at either site. In contrast, the abundance of nifH sequences was approximately 7.5 times greater (per microgram of total DNA) in mature crusts than in poorly developed crusts at a given site as measured by quantitative PCR. 16S rRNA gene clone sequencing and microscopic analysis of the cyanobacterial community within both crust types demonstrated a transition from a Microcoleus vaginatus-dominated, poorly developed crust to mature crusts harboring a greater percentage of Nostoc and Scytonema spp. We hypothesize that ecological factors, such as soil instability and water stress, may constrain the growth of N2-fixing microorganisms at our study sites and that the transition to a mature, nitrogen-producing crust initially requires bioengineering of the surface microenvironment by Microcoleus vaginatus.

  2. Diazotrophic Community Structure and Function in Two Successional Stages of Biological Soil Crusts from the Colorado Plateau and Chihuahuan Desert

    PubMed Central

    Yeager, Chris M.; Kornosky, Jennifer L.; Housman, David C.; Grote, Edmund E.; Belnap, Jayne; Kuske, Cheryl R.

    2004-01-01

    The objective of this study was to characterize the community structure and activity of N2-fixing microorganisms in mature and poorly developed biological soil crusts from both the Colorado Plateau and Chihuahuan Desert. Nitrogenase activity was approximately 10 and 2.5 times higher in mature crusts than in poorly developed crusts at the Colorado Plateau site and Chihuahuan Desert site, respectively. Analysis of nifH sequences by clone sequencing and the terminal restriction fragment length polymorphism technique indicated that the crust diazotrophic community was 80 to 90% heterocystous cyanobacteria most closely related to Nostoc spp. and that the composition of N2-fixing species did not vary significantly between the poorly developed and mature crusts at either site. In contrast, the abundance of nifH sequences was approximately 7.5 times greater (per microgram of total DNA) in mature crusts than in poorly developed crusts at a given site as measured by quantitative PCR. 16S rRNA gene clone sequencing and microscopic analysis of the cyanobacterial community within both crust types demonstrated a transition from a Microcoleus vaginatus-dominated, poorly developed crust to mature crusts harboring a greater percentage of Nostoc and Scytonema spp. We hypothesize that ecological factors, such as soil instability and water stress, may constrain the growth of N2-fixing microorganisms at our study sites and that the transition to a mature, nitrogen-producing crust initially requires bioengineering of the surface microenvironment by Microcoleus vaginatus. PMID:14766579

  3. Biological soil crust effects must be included to accurately model infiltration and erosion in drylands: An example from Tabernas Badlands

    NASA Astrophysics Data System (ADS)

    Rodríguez-Caballero, Emilio; Cantón, Yolanda; Jetten, Victor

    2015-07-01

    In dryland ecosystems, runoff is mainly generated in bare areas, which are also more susceptible to water erosion than vegetated areas. These bare areas are often covered and protected by biological soil crusts (BSCs), which modify numerous physicochemical surface properties involved in runoff and erosion processes. BSCs are considered as one of the most important stabilizing factors in the soil surface, but most previous research has concentrated only on patch or hillslope-scale effects of BSCs, and their effect at coarser scales has rarely been studied. In this article, we present a new approach based on previous surface cover quantification for including the effects of BSCs in physically-based runoff and erosion modeling. The Limburg Soil Erosion Model (LISEM) was used to parameterize and simulate the effects of BSCs on runoff and erosion in a small semiarid catchment characterized by fine-textured soils and predominantly covered by BSCs. Paired model simulations under two scenarios, with and without including the effects of BSCs, were run under different rainfall intensities to evaluate the effect of BSCs on runoff and erosion under different rainfall conditions. Runoff and erosion rates recorded in the field at the catchment outlet were predicted much more accurately when BSCs were included because there was less overestimation of runoff rate, maximum runoff peaks and erosion rates in the areas dominated by BSCs. The proposed approach enables BSCs to be included in spatially distributed runoff and erosion models, improving their predictions, and may be used for evaluating how the effect of human activity on BSCs affects catchment-scale water erosion.

  4. Spatial distribution and physiology of biological soil crusts from semi-arid central Spain are related to soil chemistry and shrub cover

    Microsoft Academic Search

    Raúl Ochoa-Hueso; Rebecca R. Hernandez; José J. Pueyo; Esteban Manrique

    2011-01-01

    Despite the critical role of biological soil crusts (BSCs) in arid and semi-arid ecosystem function, few studies are found concerning the most important environmental variables affecting their distribution and physiology. This study seeks to determine soil and microenvironmental factors affecting the spatial distribution and pigment production of BSC-forming lichens and mosses in open patches of a semi-arid Mediterranean kermes oak

  5. Features of soil enzyme activities and the number of microorganisms in plantations and their relationships with soil nutrients in the Qinling Mountains, China

    Microsoft Academic Search

    Gang Fu; Zengwen Liu; Fangfang Cui

    2009-01-01

    We studied the distribution of soil nutrients, the number of soil microorganisms, soil enzyme activities, and their relationships\\u000a in pure and mixed plantations. Soil enzyme activities, the number of soil microorganisms, and soil nutrients were measured\\u000a in plantations of Chinese pine (Pinustabulaeformis), larch (Larix kaempferi), sharp tooth oak (Quercus aliena var. acuteserrata), Manchurian catalpa (Catalpa fargesii), and mixed plantations in

  6. Isolation of a significant fraction of non-phototroph diversity from a desert Biological Soil Crust

    PubMed Central

    Nunes da Rocha, Ulisses; Cadillo-Quiroz, Hinsby; Karaoz, Ulas; Rajeev, Lara; Klitgord, Niels; Dunn, Sean; Truong, Viet; Buenrostro, Mayra; Bowen, Benjamin P.; Garcia-Pichel, Ferran; Mukhopadhyay, Aindrila; Northen, Trent R.; Brodie, Eoin L.

    2015-01-01

    Biological Soil Crusts (BSCs) are organosedimentary assemblages comprised of microbes and minerals in topsoil of terrestrial environments. BSCs strongly impact soil quality in dryland ecosystems (e.g., soil structure and nutrient yields) due to pioneer species such as Microcoleus vaginatus; phototrophs that produce filaments that bind the soil together, and support an array of heterotrophic microorganisms. These microorganisms in turn contribute to soil stability and biogeochemistry of BSCs. Non-cyanobacterial populations of BSCs are less well known than cyanobacterial populations. Therefore, we attempted to isolate a broad range of numerically significant and phylogenetically representative BSC aerobic heterotrophs. Combining simple pre-treatments (hydration of BSCs under dark and light) and isolation strategies (media with varying nutrient availability and protection from oxidative stress) we recovered 402 bacterial and one fungal isolate in axenic culture, which comprised 116 phylotypes (at 97% 16S rRNA gene sequence homology), 115 bacterial and one fungal. Each medium enriched a mostly distinct subset of phylotypes, and cultivated phylotypes varied due to the BSC pre-treatment. The fraction of the total phylotype diversity isolated, weighted by relative abundance in the community, was determined by the overlap between isolate sequences and OTUs reconstructed from metagenome or metatranscriptome reads. Together, more than 8% of relative abundance of OTUs in the metagenome was represented by our isolates, a cultivation efficiency much larger than typically expected from most soils. We conclude that simple cultivation procedures combined with specific pre-treatment of samples afford a significant reduction in the culturability gap, enabling physiological and metabolic assays that rely on ecologically relevant axenic cultures. PMID:25926821

  7. Soil microbial activity, nitrogen cycling, and long-term changes in organic carbon pools as related to fallow tillage management

    Microsoft Academic Search

    J. W Doran; E. T Elliott; K Paustian

    1998-01-01

    Two experiments were established in 1969 and 1970 near Sidney, NE, to determine the effect of moldboard plow (plow), sub-tillage (sub-till), and no-tillage (no-till) fallow management on soil properties, biological activities, and carbon and nitrogen cycling. One experiment was on land which had been broken from sod in 1920, seeded to crested wheatgrass [Agropyron cristatum (L.) Gaertn.] from 1957 to

  8. Application of soil enzyme activity test kit in a field experiment

    Microsoft Academic Search

    Milja Vepsäläinen; Sanna Kukkonen; Mauritz Vestberg; Hannu Sirviö; R Maarit Niemi

    2001-01-01

    We developed a test kit utilizing fluorogenic substrate analogues for the measurement of several enzyme activities in soil samples. Our hypothesis was that the pattern of different enzyme activities reflects changes in microbial structure and activity in a more sensitive way than total microbial biomass or activities of individual enzymes. In the test kit activities of 11 soil enzymes were

  9. Azaglycomimetics: Natural Occurrence, Biological Activity, and Application

    NASA Astrophysics Data System (ADS)

    Asano, Naoki

    A large number of alkaloids mimicking the structures of monosaccharides or oligosaccharides have been isolated from plants and microorganisms. The sugar mimicking alkaloids with a nitrogen in the ring are called azasugars or iminosugars. Naturally occurring azasugars are classified into five structural classes: polyhydroxylated piperidines, pyrrolidines, indolizidines, pyrrolizidines, and nortropanes. They are easily soluble in water because of their polyhydroxylated structures and inhibit glycosidases because of a structural resemblance to the sugar moiety of the natural substrate. Glycosidases are involved in a wide range of anabolic and catabolic processes, such as digestion, lysosomal catabolism of glycoconjugates, biosynthesis of glycoproteins, and the endoplasmic reticulum (ER) quality control and ER-associated degradation of glycoproteins. Hence, modifying or blocking these processes in vivo by inhibitors is of great interest from a therapeutic point of view. Azasugars are an important class of glycosidase inhibitors and are arousing great interest for instance as antidiabetics, antiobesity drugs, antivirals, and therapeutic agents for some genetic disorders. This review describes the recent studies on isolation, characterization, glycosidase inhibitory activity, and therapeutic application of azaglycomimetics.

  10. Point-Light Biological Motion Perception Activates Human Premotor Cortex

    Microsoft Academic Search

    Ayse Pinar Saygin; Stephen M. Wilson; Donald J. Hagler Jr; Elizabeth Bates; Martin I. Sereno

    2004-01-01

    Motion cues can be surprisingly powerful in defining objects and events. Specifically, a handful of point-lights attached to the joints of a human actor will evoke a vivid percept of action when the body is in motion. The perception of point-light biological motion activates posterior cortical areas of the brain. On the other hand, observation of others' actions is known

  11. Modeling Radial Holoblastic Cleavage: A Laboratory Activity for Developmental Biology.

    ERIC Educational Resources Information Center

    Ellis, Linda K.

    2000-01-01

    Introduces a laboratory activity designed for an undergraduate developmental biology course. Uses Play-Doh (plastic modeling clay) to build a multicellular embryo in order to provide a 3-D demonstration of cleavage. Includes notes for the instructor and student directions. (YDS)

  12. Biological activity of common mullein, a medicinal plant

    Microsoft Academic Search

    Arzu Ucar Turker; N. D Camper

    2002-01-01

    Common Mullein (Verbascum thapsus L., Scrophulariaceae) is a medicinal plant that has been used for the treatment of inflammatory diseases, asthma, spasmodic coughs, diarrhea and other pulmonary problems. The objective of this study was to assess the biological activity of Common Mullein extracts and commercial Mullein products using selected bench top bioassays, including antibacterial, antitumor, and two toxicity assays—brine shrimp

  13. Water-soluble magnetic nanoparticles with biologically active stabilizers

    Microsoft Academic Search

    Alla Zablotskaya; Izolda Segal; Edmunds Lukevics; Mikhail Maiorov; Dmitry Zablotsky; Elmars Blums; Irina Shestakova; Ilona Domracheva

    2009-01-01

    We present the results of the interaction of iron oxide nanoparticles with some biologically active surfactants, namely, oleic acid and cytotoxic alkanolamine derivatives. Physico-chemical properties, as magnetization, magnetite concentration and particle diameter, of the prepared magnetic samples were studied. The nanoparticle size of 11nm for toluene magnetic fluid determined by TEM is in good agreement with the data obtained by

  14. The microbiology of biological phosphorus removal in activated sludge systems

    Microsoft Academic Search

    Robert J Seviour; Takashi Mino; Motoharu Onuki

    2003-01-01

    Activated sludge systems are designed and operated globally to remove phosphorus microbiologically, a process called enhanced biological phosphorus removal (EBPR). Yet little is still known about the ecology of EBPR processes, the microbes involved, their functions there and the possible reasons why they often perform unreliably. The application of rRNA-based methods to analyze EBPR community structure has changed dramatically our

  15. Comparison between geochemical and biological estimates of subsurface microbial activities

    Microsoft Academic Search

    T. J. Phelps; E. M. Murphy; S. M. Pfiffner; D. C. White

    1994-01-01

    Geochemical and biological estimates of in situ microbial activities were compared from the aerobic and microaerophilic sediments of the Atlantic Coastal Plain. Radioisotope time-course experiments suggested oxidation rates greater than millimolar quantities per year for acetate and glucose. Geochemical analyses assessing oxygen consumption, soluble organic carbon utilization, sulfate reduction, and carbon dioxide production suggested organic oxidation rates of nano- to

  16. Modelling biological nutrient removal activated sludge systems—a review

    Microsoft Academic Search

    Zhi-rong Hu; M. C Wentzel; G. A Ekama

    2003-01-01

    The external nitrification (EN) biological nutrient removal (BNR) activated sludge (ENBNRAS) system shows considerable promise for full-scale implementation. As an aid for this implementation, a mathematical simulation model would be an invaluable tool. To develop such a model, a study was conducted to select the most suitable simulation model to serve as a starting point for further development. For this,

  17. EXTERNAL NITRIFICATION IN BIOLOGICAL NUTRIENT REMOVAL ACTIVATED SLUDGE SYSTEMS

    Microsoft Academic Search

    Z Hu; M C Wentzel; G A Ekama

    SUMMARY A biological nutrient removal (BNR) activated sludge (AS) scheme incorporating external nitrification in a fixed media system is evaluated. A laboratory scale investigation of the scheme indicates that it holds considerable potential for BNRAS system intensification through major reduction in sludge age and oxygen demand and significant improvement in sludge settleability. Because the BNRAS system is not required to

  18. Biological activities and medicinal properties of neem (Azadirachta indica)

    Microsoft Academic Search

    Kausik Biswas; Ishita Chattopadhyay; Ranajit K. Banerjee; Uday Bandyopadhyay

    Neem (Azadirachta indica A. Juss) is perhaps the most useful traditional medicinal plant in India. Each part of the neem tree has some medicinal property and is thus commercially exploitable. During the last five decades, apart from the chemistry of the neem com- pounds, considerable progress has been achieved regarding the biological activity and medicinal appli - cations of neem.

  19. Learning to See Biological Motion: Brain Activity Parallels Behavior

    Microsoft Academic Search

    Emily D. Grossman; Randolph Blake; Chai-Youn Kim

    2004-01-01

    Individuals improve with practice on a variety of perceptual tasks, presumably reflecting plasticity in underlying neural mechanisms. We trained observers to discriminate biological motion from scrambled (nonbiological) motion and examined whether the resulting improvement in perceptual performance was accompanied by changes in activation within the posterior superior temporal sulcus and the fusiform face area, brain areas involved in perception of

  20. Effects of long term irrigation with polluted water and sludge amendment on some soil enzyme activities

    SciTech Connect

    Topac, F.O.; Baskaya, H.S.; Alkan, U.; Katkat, A.V. [Uludag University, Bursa (Turkey)

    2008-01-15

    The objective of this study was to determine the effects of wastewater sludge-fly ash mixtures on urease, dehydrogenase, alkaline phosphatase and beta-glucosidase activities in soils. In order to evaluate the probable effects of previous soil management practices (irrigation with polluted water) on soil enzymes, two different soil samples which were similar in physical properties, but different in irrigation practice were used. The application of wastewater sludges supplemented with varying doses of fly ash increased potential enzyme activities for a short period of time (3 months) in comparison to unamended soils. However, the activity levels generally showed a decreasing trend with increasing ash ratios indicating the inhibitory effect of fly ash. The urease and dehydrogenase activities were particularly lower in soils irrigated from a polluted stream, indicating the negative effects of the previous soil management on soil microbial activity.

  1. Root-Parasitic Nematodes Enhance Soil Microbial Activities and Nitrogen Mineralization

    Microsoft Academic Search

    C. Tu; S. R. Koenning; S. Hu

    2003-01-01

    Obligate root-parasitic nematodes can affect soil microbes positively by enhancing C and nutrient leakage from roots but negatively by restricting total root growth. However, it is unclear how the resulting changes in C availability affect soil microbial activities and N cycling. In a microplot experiment, effects of root-parasitic reniform nematodes (Rotylenchulus reniformis) on soil microbial biomass and activities were examined

  2. ENZYME ACTIVITIES AS AFFECTED BY SOIL PROPERTIES AND LAND USE IN A TROPICAL WATERSHED

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enzyme activities play key roles in the biochemical functioning of soils, including soil organic matter formation and degradation, nutrient cycling, and decomposition of xenobiotics. Knowledge of enzyme activities can be used to describe changes in soil quality due to land use management and for un...

  3. Comparative studies on the soil enzymic activities of two plant communities in the Yellow River delta

    Microsoft Academic Search

    Di Cao; Fuchen Shi; Zhaohua Lu; Zhigang Yao; Jingtao Liu

    2011-01-01

    Soil enzyme plays an active role in the material recycling and energy flow of soil biochemical process. This article dealed with the month changes of catalase?? dehydrogenase?? phosphatase?? urease?? protease in Suaeda salsa and Aeluropus sinensis in the Yellow River Delta. Meanwhile, the relationship between the soil enzyme activities and physical-chemical factors was discussed by correlation analysis. The results showed:

  4. Soil Biology & Biochemistry 38 (2006) 30573064 Fungal diversity in soils and historic wood from

    E-print Network

    Blanchette, Robert A.

    2006-01-01

    the Ross Sea Region of Antarctica Brett E. Arenza,Ă, Benjamin W. Helda , Joel A. Jurgensa , Roberta L human activity as compared to those that are remote and relatively pristine. Ross Island, Antarctica is the site of three historic expedition huts left by early explorers to the South Pole, Robert F. Scott

  5. Soil organic carbon and biological fertility in a Mediterranean forest area (Italy)

    NASA Astrophysics Data System (ADS)

    Francaviglia, Rosa; Benedetti, Anna

    2015-04-01

    The study was performed at Castelporziano Estate, a natural ecosystem with high environmental value, and not concerned with any direct sources of pollution. However, it is situated near the city of Rome, some industrial plants, the international airport of Fiumicino, and some highways that can represent an external source of pollutants. Castelporziano lies in Central Italy at the western outskirts of Rome, about 20 km from the city centre and in front of the Tyrrhenian Sea. Soil morphology is mainly plain (30 m mean elevation) with sandy materials of alluvial nature, and only the inner part is formed of volcanic and alluvial materials with a slight elevation above the sea level (85 m). The total area is about 6000 ha, the climate is Mediterranean, total rainfall is 700 mm, and mean temperatures range from 4 ° C in winter and 30 ° C in summer. The vegetation is typically Mediterranean, mainly oaks, mixed broadleaf groves, and Mediterranean maquis along the seacoast. Areas with reforestation of pines, as well as corkwoods, pastures, and small agricultural fields are also present. Soils were sampled at five different sites: QI, forest of Quercus ilex L.; MM, Mediterranean maquis; PP, Pinus pinea L. reforestation (60 years old); MF, mixed hygrophilous back-dune forest; AR, arable land. Five soil samples from each site were collected (0-20 cm of depth), about 2 m far from each other. Soil organic carbon (SOC), total N (Ntot), microbial biomass carbon (Cmic), basal and cumulative respiration (Cbas and Ccum), the metabolic quotient (qCO2), and the mineralisation quotient (qM) were determined. The index of biological fertility (IBF), a comprehensive indicator considering SOM, Cbas, Ccum, Cmic, qCO2 and qM was also calculated for the different land uses. Five intervals of values have been set for each parameter, and a score increasing from 1 to 5 has been assigned to each interval; the algebraic sum of the score for each parameter gives the classes of biological fertility.

  6. Soil persistence of Bacillus thuringiensis (Bt) toxin from transgenic Bt cotton tissues and its effect on soil enzyme activities

    Microsoft Academic Search

    C. X. Sun; L. J. Chen; Z. J. Wu; L. K. Zhou; H. Shimizu

    2007-01-01

    A silty loam soil was incubated with the leaves and stems of two transgenic Bacillus thuringiensis (Bt) cotton varieties and nontransgenic Bt cotton to study the soil persistence of the Bt toxin from the decomposing transgenic\\u000a Bt cotton tissues and its effect on soil enzyme activities. The results showed that after Bt cotton tissue amendment, Bt toxin\\u000a was introduced into

  7. Global change and biological soil crusts: Effects of ultraviolet augmentation under altered precipitation regimes and nitrogen additions

    USGS Publications Warehouse

    Belnap, J.; Phillips, S.L.; Flint, S.; Money, J.; Caldwell, M.

    2008-01-01

    Biological soil crusts (BSCs), a consortium of cyanobacteria, lichens, and mosses, are essential in most dryland ecosystems. As these organisms are relatively immobile and occur on the soil surface, they are exposed to high levels of ultraviolet (UV) radiation and atmospheric nitrogen (N) deposition, rising temperatures, and alterations in precipitation patterns. In this study, we applied treatments to three types of BSCs (early, medium, and late successional) over three time periods (spring, summer, and spring-fall). In the first year, we augmented UV and altered precipitation patterns, and in the second year, we augmented UV and N. In the first year, with average air temperatures, we saw little response to our treatments except quantum yield, which was reduced in dark BSCs during one of three sample times and in Collema BSCs two of three sample times. There was more response to UV augmentation the second year when air temperatures were above average. Declines were seen in 21% of the measured variables, including quantum yield, chlorophyll a, UV-protective pigments, nitrogenase activity, and extracellular polysaccharides. N additions had some negative effects on light and dark BSCs, including the reduction of quantum yield, ??-carotene, nitrogenase activity, scytonemin, and xanthophylls. N addition had no effects on the Collema BSCs. When N was added to samples that had received augmented UV, there were only limited effects relative to samples that received UV without N. These results indicate that the negative effect of UV and altered precipitation on BSCs will be heightened as global temperatures increase, and that as their ability to produce UV-protective pigments is compromised, physiological functioning will be impaired. N deposition will only ameliorate UV impacts in a limited number of cases. Overall, increases in UV will likely lead to lowered productivity and increased mortality in BSCs through time, which, in turn, will reduce their ability to contribute to the stability and fertility of soils in dryland regions. ?? 2008 The Authors Journal compilation ?? 2008 Blackwell Publishing Ltd.

  8. Temporal and soil depth-related variation in soil enzyme activities and in root growth of red clover ( Trifolium pratense) and timothy ( Phleum pratense) in the field

    Microsoft Academic Search

    R. M. Niemi; M. Vepsäläinen; K. Wallenius; S. Simpanen; L. Alakukku; L. Pietola

    2005-01-01

    Activities of 12 different enzymes in soil and growth of timothy (Phleum pratense) and red clover (Trifolium pratense) roots were monitored on fine sand soil (Aquic Haplocryoll) throughout the third growing season of the plants. Both root biomass and enzyme activities decreased with increasing soil depth. The root biomass depended on the plant, the soil depth and the date within

  9. The influence of time, storage temperature, and substrate age on potential soil enzyme activity in acidic forest soils using MUB-linked substrates and l-DOPA

    Microsoft Academic Search

    Jared L. DeForest

    2009-01-01

    The purpose of this experiment was to evaluate whether soil storage and processing methods significantly influence measurements of potential in situ enzyme activity in acidic forest soils. More specifically, the objectives were to determine if: (1) duration and temperature of soil storage; (2) duration of soil slurry in buffer; and (3) age of model substrates significantly influence the activity of

  10. Chemical properties and toxicity of soils contaminated by mining activity.

    PubMed

    Agnieszka, Baran; Tomasz, Czech; Jerzy, Wieczorek

    2014-09-01

    This research is aimed at assessing the total content and soluble forms of metals (zinc, lead and cadmium) and toxicity of soils subjected to strong human pressure associated with mining of zinc and lead ores. The research area lay in the neighbourhood of the Boles?aw Mine and Metallurgical Plant in Bukowno (Poland). The study obtained total cadmium concentration between 0.29 and 51.91 mg, zinc between 7.90 and 3,614 mg, and that of lead between 28.4 and 6844 mg kg(-1) of soil d.m. The solubility of the heavy metals in 1 mol dm(-3) NH4NO3 was 1-49% for zinc, 5-45% for cadmium, and <1-10% for lead. In 1 mol HCl dm(-3), the solubility of the studied metals was much higher and obtained values depending on the collection site, from 45 to 92% for zinc, from 74 to 99%, and from 79 to 99% for lead. The lower solubility of the heavy metals in 1 mol dm(-3) NH4NO3 than 1 mol HCl dm(-3) is connected with that, the ammonium nitrate has low extraction power, and it is used in determining the bioavailable (active) form of heavy metals. Toxicity assessment of the soil samples was performed using two tests, Phytotoxkit and Microtox(®). Germination index values were between 22 and 75% for Sinapis alba, between 28 and 100% for Lepidium sativum, and between 10 and 28% for Sorghum saccharatum. Depending on the studied soil sample, Vibrio fischeri luminescence inhibition was 20-96%. The sensitivity of the test organisms formed the following series: S. saccharatum > S. alba = V. fischeri > L. sativum. Significant positive correlations (p ? 0.05) of the total and soluble contents of the metals with luminescence inhibition in V. fischeri and root growth inhibition in S. saccharatum were found. The general trend observed was an increase in metal toxicity measured by the biotest with increasing available metal contents in soils. All the soil samples were classified into toxicity class III, which means that they are toxic and present severe danger. Biotest are a good complement to chemical analyses in the assessment of quality of soils as well as in properly managing them. PMID:24903806

  11. Methanogens at the top of the world: occurrence and potential activity of methanogens in newly deglaciated soils in high-altitude cold deserts in the Western Himalayas

    PubMed Central

    Aschenbach, Katrin; Conrad, Ralf; ?eháková, Klára; Doležal, Ji?í; Janatková, Kate?ina; Angel, Roey

    2013-01-01

    Methanogens typically occur in reduced anoxic environments. However, in recent studies it has been shown that many aerated upland soils, including desert soils also host active methanogens. Here we show that soil samples from high-altitude cold deserts in the western Himalayas (Ladakh, India) produce CH4 after incubation as slurry under anoxic conditions at rates comparable to those of hot desert soils. Samples of matured soil from three different vegetation belts (arid, steppe, and subnival) were compared with younger soils originating from frontal and lateral moraines of receding glaciers. While methanogenic rates were higher in the samples from matured soils, CH4 was also produced in the samples from the recently deglaciated moraines. In both young and matured soils, those covered by a biological soil crust (biocrust) were more active than their bare counterparts. Isotopic analysis showed that in both cases CH4 was initially produced from H2/CO2 but later mostly from acetate. Analysis of the archaeal community in the in situ soil samples revealed a clear dominance of sequences related to Thaumarchaeota, while the methanogenic community comprised only a minor fraction of the archaeal community. Similar to other aerated soils, the methanogenic community was comprised almost solely of the genera Methanosarcina and Methanocella, and possibly also Methanobacterium in some cases. Nevertheless, ~103 gdw?1 soil methanogens were already present in the young moraine soil together with cyanobacteria. Our results demonstrate that Methanosarcina and Methanocella not only tolerate atmospheric oxygen but are also able to survive in these harsh cold environments. Their occurrence in newly deglaciated soils shows that they are early colonizers of desert soils, similar to cyanobacteria, and may play a role in the development of desert biocrusts. PMID:24348469

  12. From molecular activities and processes to biological function.

    PubMed

    van Helden, J; Naim, A; Lemer, C; Mancuso, R; Eldridge, M; Wodak, S J

    2001-03-01

    This paper describes how biological function can be represented in terms of molecular activities and processes. It presents several key features of a data model that is based on a conceptual description of the network of interactions between molecular entities within the cell and between cells. This model is implemented in the aMAZE database that presently deals with information on metabolic pathways, gene regulation, sub- or supracellular locations, and transport. It is shown that this model constitutes a useful generalisation of data representations currently implemented in metabolic pathway databases, and that it can furthermore include multiple schemes for categorising and classifying molecular entities, activities, processes and localisations. In particular, we highlight the flexibility offered by our system in representing multiple molecular activities and their control, in viewing biological function at different levels of resolution and in updating this view as our knowledge evolves. PMID:11465065

  13. Biological Activities of Phenolic Compounds Present in Virgin Olive Oil

    PubMed Central

    Cicerale, Sara; Lucas, Lisa; Keast, Russell

    2010-01-01

    The Mediterranean diet is associated with a lower incidence of atherosclerosis, cardiovascular disease, neurodegenerative diseases and certain types of cancer. The apparent health benefits have been partially ascribed to the dietary consumption of virgin olive oil by Mediterranean populations. Much research has focused on the biologically active phenolic compounds naturally present in virgin olive oils to aid in explaining reduced mortality and morbidity experienced by people consuming a traditional Mediterranean diet. Studies (human, animal, in vivo and in vitro) have demonstrated that olive oil phenolic compounds have positive effects on certain physiological parameters, such as plasma lipoproteins, oxidative damage, inflammatory markers, platelet and cellular function, antimicrobial activity and bone health. This paper summarizes current knowledge on the bioavailability and biological activities of olive oil phenolic compounds. PMID:20386648

  14. Similar Biological Activities of Two Isostructural Ruthenium and Osmium Complexes

    SciTech Connect

    Maksimoska,J.; Williams, D.; Atilla-Gokcumen, G.; Smalley, K.; Carroll, P.; Webster, R.; Filippakopoulos, P.; Knapp, S.; Herlyn, M.; Meggers, E.

    2008-01-01

    In this study, we probe and verify the concept of designing unreactive bioactive metal complexes, in which the metal possesses a purely structural function, by investigating the consequences of replacing ruthenium in a bioactive half-sandwich kinase inhibitor scaffold by its heavier congener osmium. The two isostructural complexes are compared with respect to their anticancer properties in 1205?Lu melanoma cells, activation of the Wnt signaling pathway, IC50 values against the protein kinases GSK-3? and Pim-1, and binding modes to the protein kinase Pim-1 by protein crystallography. It was found that the two congeners display almost indistinguishable biological activities, which can be explained by their nearly identical three-dimensional structures and their identical mode of action as protein kinase inhibitors. This is a unique example in which the replacement of a metal in an anticancer scaffold by its heavier homologue does not alter its biological activity.

  15. 78 FR 56153 - National Environmental Policy Act: Categorical Exclusions for Soil and Water Restoration Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-12

    ...Act: Categorical Exclusions for Soil and Water Restoration Activities AGENCY: Forest...that restore lands negatively impacted by water control structures, disturbance events...potential environmental effects of soil and water restoration projects that are...

  16. Changes in physical and biological soil quality indicators in a tropical crop system (Havana, Cuba) in response to different agroecological management practices.

    PubMed

    Izquierdo, I; Caravaca, F; Alguacil, M M; Roldán, A

    2003-11-01

    The objective of our study was to assess the response of physical (aggregate stability and bulk density) and biological (enzyme activities and microbial biomass) soil quality indicators to the adoption of agroecological management practices, such as the planting of forage species (forage area) and the rotation of local crops (polycrop area), carried out in a representative tropical pasture on an integrated livestock-crop farm. The pasture system was used as control (pasture area). In all three areas, the values of water-soluble C were higher in the rainy season compared to the dry season. Pasture and forage areas had the highest percentage of stable aggregates in the rainy season, while polycrops developed soils with less stable aggregates. Soil bulk density was lower in the pasture and forage areas than in the polycrop area. In the pasture area, the microbial biomass C values, dehydrogenase, urease, protease-BAA, acid phosphatase, and beta-glucosidase activities were higher than in the forage and polycrop areas, particularly in the dry season. The highest increase in the microbial biomass C in the rainy season, with respect to the dry season, was recorded in the pasture area (about 1.2-fold). In conclusion, the planting of forage species can be considered an effective practice for carrying out sustainable, integrated livestock-crop systems, due to its general maintenance of soil quality, while the adoption of polycrop rotations appears to be less favorable because it decreases soil quality. PMID:15015701

  17. Isothiocyanate synthetic analogs: biological activities, structure-activity relationships and synthetic strategies.

    PubMed

    Milelli, Andrea; Fimognari, Carmela; Ticchi, Nicole; Neviani, Paolo; Minarini, Anna; Tumiatti, Vincenzo

    2014-01-01

    Sulforaphane is a natural product that is constantly under biological investigation for its unique biological properties. This naturally occurring isothiocyanate (ITC) and its analogs are the main components of cruciferous vegetables, such as cauliflower, watercress, broccoli, cabbage, Brussels sprouts, widely used as chemopreventive agents. Due to their interesting biological profiles, natural ITCs have been exploited as starting point to develop new synthetic analogs. The present mini-review briefly highlights the most important biological actions of selected new synthetic ITCs focusing on their structure-activity relationships and related synthetic strategies. PMID:25373847

  18. Amendment application in a multi-contaminated mine soil: effects on soil enzymatic activities and ecotoxicological characteristics.

    PubMed

    Manzano, Rebeca; Esteban, Elvira; Peńalosa, Jesús M; Alvarenga, Paula

    2014-03-01

    Several amendments were tested on soils obtained from an arsenopyrite mine, further planted with Arrhenatherum elatius and Festuca curvifolia, in order to assess their ability to improve soil's ecotoxicological characteristics. The properties used to assess the effects were: soil enzymatic activities (dehydrogenase, ?-glucosidase, acid phosphatase, urease, protease and cellulase), terrestrial bioassays (Eisenia fetida mortality and avoidance behaviour), and aquatic bioassays using a soil leachate (Daphnia magna immobilisation and Vibrio fischeri bioluminescence inhibition). The treatment with FeSO4 1 % w/w was able to reduce extractable As in soil, but increased the extractable Cu, Mn and Zn concentrations, as a consequence of the decrease in soil pH, in relation to the unamended soil, from 5.0 to 3.4, respectively. As a consequence, this treatment had a detrimental effect in some of the soil enzymatic activities (e.g. dehydrogenase, acid phosphatase, urease and cellulase), did not allow plant growth, induced E. fetida mortality in the highest concentration tested (100 % w/w), and its soil leachate was very toxic towards D. magna and V. fischeri. The combined application of FeSO4 1 % w/w with other treatments (e.g. CaCO3 1 % w/w and paper mill 1 % w/w) allowed a decrease in extractable As and metals, and a soil pH value closer to neutrality. As a consequence, dehydrogenase activity, plant growth and some of the bioassays identified those as better soil treatments to this type of multi-contaminated soil. PMID:24337998

  19. The effect of fertilisation on soil nitrifier activity in experimental grassland plots

    Microsoft Academic Search

    D. W. Hopkins; A. G. O'Donnell; R. S. Shiel

    1988-01-01

    Soil nitrification was compared in soils from 89-year-old grassland experimental plots with diverse chemical characteristics. Measurements of NaClO3-inhibited short-term nitrifier activity (SNA) and deamination of 1,2-diamino-4-nitrobenzene were used to study nitrification and deamination activities, respectively, in soil from each of 12 plots. Using multiple regression analysis, an expression for the relationship between SNA, soil pH and fertiliser N additions was

  20. Regulation of soil enzyme activities in constructed wetlands under a short-term drying period

    Microsoft Academic Search

    Nguyen Xuan Que Vo; Hojeong Kang

    2012-01-01

    The activities of extracellular enzymes are important in understanding decomposition of soil organic matter in wetlands subjecting to drying. The activity of soil extracellular enzymes (?-glucosidase, N-acetylglucosaminidase, and phosphatase), and related physicochemical parameters were monitored in constructed freshwater wetlands during a one-month drying manipulation. Drying increased redox potential and decreased soil water content significantly (P<0.05). Higher content of soil organic

  1. Soil Microbial Biomass, Basal Respiration and Enzyme Activity of Main Forest Types in the Qinling Mountains

    PubMed Central

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  2. Models to support active sensing of biological aerosol clouds

    NASA Astrophysics Data System (ADS)

    Brown, Andrea M.; Kalter, Jeffrey M.; Corson, Elizabeth C.; Chaudhry, Zahra; Boggs, Nathan T.; Brown, David M.; Thomas, Michael E.; Carter, Christopher C.

    2013-05-01

    Elastic backscatter LIght Detection And Ranging (LIDAR) is a promising approach for stand-off detection of biological aerosol clouds. Comprehensive models that explain the scattering behavior from the aerosol cloud are needed to understand and predict the scattering signatures of biological aerosols under varying atmospheric conditions and against different aerosol backgrounds. Elastic signatures are dependent on many parameters of the aerosol cloud, with two major components being the size distribution and refractive index of the aerosols. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) has been in a unique position to measure the size distributions of released biological simulant clouds using a wide assortment of aerosol characterization systems that are available on the commercial market. In conjunction with the size distribution measurements, JHU/APL has also been making a dedicated effort to properly measure the refractive indices of the released materials using a thin-film absorption technique and laboratory characterization of the released materials. Intimate knowledge of the size distributions and refractive indices of the biological aerosols provides JHU/APL with powerful tools to build elastic scattering models, with the purpose of understanding, and ultimately, predicting the active signatures of biological clouds.

  3. Combined effects of bacterial-feeding nematodes and prometryne on the soil microbial activity.

    PubMed

    Zhou, Jihai; Li, Xuechao; Jiang, Ying; Wu, Yue; Chen, Jiandong; Hu, Feng; Li, Huixin

    2011-09-15

    Microcosm experiments were carried out to study the effects of bacterial-feeding nematodes and indigenous microbes and their interactions on the degradation of prometryne and soil microbial activity in contaminated soil. The results showed that soil indigenous microbes could degrade prometryne up to 59.6-67.9%; bacterial-feeding nematodes accelerated the degradation of prometryne in contaminated soil, and prometryne degradation was raised by 8.36-10.69%. Soil microbial biomass C (C(mic)), basal soil respiration (BSR), and respiratory quotient (qCO(2)) increased in the beginning of the experiment and decreased in the later stage of the experiment. Nematodes grew and reproduced quite fast, and did increase the growth of soil microbes and enhance soil microbial activity in prometryne contaminated soil during the incubation period. PMID:21752543

  4. Summer drought decreases soil fungal diversity and associated phenol oxidase activity in upland Calluna heathland soil.

    PubMed

    Toberman, Hannah; Freeman, Chris; Evans, Chris; Fenner, Nathalie; Artz, Rebekka R E

    2008-11-01

    Natural moisture limitation during summer drought can constitute a stress for microbial communities in soil. Given globally predicted increases in drought frequency, there is an urgent need for a greater understanding of the effects of drought events on soil microbial processes. Using a long-term field-scale drought manipulation experiment at Clocaenog, Wales, UK, we analysed fungal community dynamics, using internal transcribed spacer-denaturing gradient gel electrophoresis (DGGE), over a 1-year period in the 6th year of drought manipulation. Ambient seasonality was found to be the dominant factor driving variation in fungal community dynamics. The summer drought manipulation resulted in a significant decline in the abundance of dominant fungal species, both independently of, and in interaction with, this seasonal variation. Furthermore, soil moisture was significantly correlated with the changes in fungal diversity over the drought manipulation period. While the relationship between species diversity and functional diversity remains equivocal, phenol oxidase activity was decreased by the summer drought conditions and there was a significant correlation with the decline of DGGE band richness among the most dominant fungal species during the drought season. Climatically driven events such as droughts may have significant implications for fungal community diversity and therefore, have the potential to interfere with crucial ecosystem processes, such as organic matter decomposition. PMID:18662311

  5. Microbial biomass, activity, and organic matter accumulation in soils contaminated with heavy metals

    Microsoft Academic Search

    Giovanni Valsecchi; Carmen Gigliotti; Anna Farini

    1995-01-01

    Chemical characteristics and some parameters related to biological components were determined in 16 soils from a fairly homogeneous area in the north of Italy, contaminated with different levels of heavy metals. Correlation analysis of the parameters studied showed close positive relationships among the metals and with the organic C content in the soils studied. Negative relationships were observed among the

  6. The biological activity of Zeise's salt and its derivatives.

    PubMed

    Meieranz, Sandra; Stefanopoulou, Maria; Rubner, Gerhard; Bensdorf, Kerstin; Kubutat, Dominic; Sheldrick, William S; Gust, Ronald

    2015-02-23

    With the aim to design new biologically active bioinorganic drugs of aspirin, whose mode of action is based on the inhibition of the cyclooxygenase(COX) enzymes, derivatives of Zeise's salt were synthesized in this structure-activity relationship study. Surprisingly, not only these Zeise-aspirin compounds but also Zeise's salt itself showed high inhibitory potency against COX enzymes in in?vitro assays. In contrast, potassium tetrachloroplatinate and cisplatin did not influence the enzyme activity at equimolar concentrations. It was demonstrated by LC-ESI tandem-mass spectrometry that Zeise's salt platinates the essential amino acids Tyr385 (active site of the enzyme) and Ser516 (will be acetylated by aspirin) of COX-1, thereby strongly impairing the function of the enzyme. This finding demonstrates for the first time that Zeise's salt is pharmacologically active and is a potent enzyme inhibitor. PMID:25604474

  7. Impact of soil characteristics on piping activity in a mountainous area under a temperate climate (Polish Bieszczady Mts., Eastern Carpathians)

    NASA Astrophysics Data System (ADS)

    Bernatek, Anita; Kacprzak, Andrzej; Stolarczyk, Mateusz

    2015-04-01

    Piping leads to the formation of subsurface channels (pipes) by concentrated flowing water, which may result in the collapse of soil surface and formation of discontinuous gullies. The significance of piping in gully erosion with the recognition of favourable soil properties is widely described in badlands with dispersive materials and in loess-covered hilly regions. Piping conditions in other regions - without dispersive materials or without loess - draw hardly any attention. Therefore, this research aims at a better understanding of the role of soil characteristics in piping activity in a mountainous area with Flysch-derived soils under a temperate climate. The survey was carried out in the Tyskowa catchment, in the Polish Bieszczady Mts. (Eastern Carpathians), where pipes develop at a depth ranging from 0.70 to 1.30 m. We focused on soil characteristics that can impact erodibility, including particle size distribution, structure, consistency, and bulk density. These characteristics as well as selected chemical properties (pH, exchangeable cations, sodium absorption ratio - SAR) were studied in detail for 4 soil profiles with a different position in relation to collapsed pipes (CPs): on a slope with abundant CPs and on one lacking CPs, in the axis of a pipe (above it) and in a piping sinkhole. We tested a hypothesis that soil properties control the occurrence of pipes and we checked if there is any difference in soil properties on slopes with and without CPs. Moreover, we compared soil profiles within the slope with CPs. As to the hypothesis, no clear difference in soils characteristics was observed between the slope with high piping activity and the one without it. At both sites typical Cambisols profiles were developed with high clay-silt content (% silt: mean A=60, standard deviation SD=6.55; % clay: A=27, SD=8.07), which potentially enhances piping. However, the profiles at the site above CPs (in the axis of a pipe, where potentially a pipe will develop) and in a sinkhole are characterised by intense biological activity and development of soil structure in deeper horizons (angular and subangular blocky down to 90-105 cm). Comparing the sites without CPs, this activity is lower and aggregate soil structure is developed down to 50-60 cm. The chemical properties do not differ. The analysed soils are not dispersive (e.g. SAR <0.1). To summarize, intense biological activity favours the development of pipes in the study area. The development of soil structure allows water infiltration down the profile, which is necessary to pipe development. Combining all results from the soil profiles and the depth of pipes indicate that pipes develop between solum (A and B horizon) and subsoil (C horizon). This study is supported by the National Centre of Science, Poland (DEC-2012/05/N/ST10/03926).

  8. Removal of Biologically Active Organic Contaminants using Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Banks, Michael A. (Inventor); Banks, Eric B. (Inventor)

    2003-01-01

    Biomedical devices that are to come into contact with living tissue, such as prosthetic and other implants for the human body and the containers used to store and transport them, are together cleaned of non-living, but biologically active organic materials, including endotoxins such as lipopolysaccharides, and assembled into a hermetically sealed package without recontamination. This is achieved by cleaning both the device and package components together in an apparatus, which includes a hermetically sealed chamber, in which they are contacted with atomic oxygen which biocleans them, by oxidizing the biologically active organic materials. The apparatus also includes means for manipulating the device and container and hermetically sealing the cleaned device into the cleaned container to form the package. A calibrated witness coupon visually indicates whether or not the device and container have received enough exposure to the atomic oxygen to have removed the organic materials from their surfaces. Gamma radiation is then used to sterilize the device in the sealed container.

  9. Biological activities and medicinal properties of Cajanus cajan (L) Millsp.

    PubMed

    Pal, Dilipkumar; Mishra, Pragya; Sachan, Neetu; Ghosh, Ashoke K

    2011-10-01

    Cajanus cajan (L) Millsp. (Sanskrit: Adhaki, Hindi: Arhar, English: Pigeon pea, Bengali: Tur) (family: Fabaceae) is the most important grain legume crop of rain-fed agriculture in semi-arid tropics. It is both a food crop and a cover/forage crop with high levels of proteins and important amino acids like methionine, lysine and tryptophan. During the last few decades extensive studies have been carried out regarding the chemistry of C. cajan and considerable progress has been achieved regarding its biological activities and medicinal applications. This review article gives an overview on the biological activities of the compounds isolated, pharmacological actions and clinical studies of C. cajan extracts apart from its general details. PMID:22247887

  10. Microbial life in frozen boreal soils-environmental constraints on catabolic and anabolic activity

    NASA Astrophysics Data System (ADS)

    Oquist, M. G.; Sparrman, T.; Haei, M.; Segura, J.; Schleucher, J.; Nilsson, M. B.

    2013-12-01

    Microbial activity in frozen soils has recently gained increasing attention and the fact that soil microorganisms can perform significant metabolic activity at temperatures below freezing is apparent. However, to what extent microbial activity is constrained by the environmental conditions prevailing in a frozen soil matrix is still very uncertain. This presentation will address how the fundamental environmental factors of temperature, liquid water availability and substrate availability combine to regulate rates of catabolic and anabolic microbial processes in frozen soils. The presented results are gained from investigations of the surface layers of boreal forest soils with seasonal freezing. We show that the amount and availability of liquid water is an integral factor regulating rates of microbial activity in the frozen soil matrix and can also explain frequently observed deviations in the temperature responses of biogenic CO2 production in frozen soils, as compared to unfrozen soils. In turn, the capacity for a specific soil to retain liquid water at sub-zero temperatures is controlled by the structural composition of the soil, and especially the soil organic matter is of integral importance. We also show that the partitioning of substrate carbon, in the form of monomeric sugar (glucose), for catabolic and anabolic metabolism remain constant in the temperature range of -4C to 9C. This confirms that microbial growth may proceed even when soils are frozen. In addition we present corresponding data for organisms metabolizing polymeric substrates (cellulose) requiring exoenzymatic activity. We conclude that the metabolic response of soil microorganism to controlling factors may change substantially across the freezing point of soil water, and also the patterns of interaction among controlling factors are affected. Thus, it is evident that metabolic response functions derived from investigations of unfrozen soils cannot be superimposed on frozen soils. Nonetheless, the soil microbial population appear very adapted to seasonal freezing with respect to their metabolic performance.

  11. Soil and rhizosphere as habitats for Pseudomonas inoculants: new knowledge on distribution, activity and physiological state derived from micro-scale and single-cell studies

    Microsoft Academic Search

    Jan Sřrensen; Linda Elise Jensen; Ole Nybroe

    2001-01-01

    Pseudomonas spp. comprise an important group of bacteria used for biological control of microfungi in the plant rhizosphere. Successful performance of microbial inoculants requires both establishment, proliferation and activity under in situ conditions. To identify the factors controlling fate and performance of the inoculants, small-scale analyses are needed due to the heterogeneity characterizing the complex soil and rhizosphere environments. Direct

  12. Biological activities caused by far-infrared radiation

    Microsoft Academic Search

    Shojiro Inoué; Morihiro Kabaya

    1989-01-01

    Contrary to previous presumption, accumulated evidence indicates that far-infrared rays are biologically active. A small ceramic disk that emist far-infrared rays (4–16 µm) has commonly been applied to a local spot or a whole part of the body for exposure. Pioneering attempts to experimentally analyze an effect of acute and chronic radiation of far-infrared rays on living organisms have detected

  13. Biological activities of an extract from Cleome viscosa L. (Capparaceae)

    Microsoft Academic Search

    L. A. D. Williams; E. Vasques; W. Reid; R. Porter; W. Kraus

    2003-01-01

    Electron micrograph examination of the leaf and stem surfaces of Cleome viscosa L (Family Capparaceae) revealed the presence of secretory glandular trichomes with club-cylinder and cylinder morphologies. In the present study, the leaves and stems of C. viscosa were extracted with hexane and the extract was evaluated for the following biological activities: anti-bacterial, anti-fungal, contact insecticidal and nematicidal. The extract

  14. Indonesian propolis: chemical composition, biological activity and botanical origin

    Microsoft Academic Search

    Boryana Trusheva; Milena Popova; Eko Budi Koendhori; Iva Tsvetkova; Christo Naydenski; Vassya Bankova

    2011-01-01

    From a biologically active extract of Indonesian propolis from East Java, 11 compounds were isolated and identified: four alk(en)ylresorcinols (obtained as an inseparable mixture) (1–4) were isolated for the first time from propolis, along with four prenylflavanones (6–9) and three cycloartane-type triterpenes (5, 10 and 11). The structures of the components were elucidated based on their spectral properties. All prenylflavanones

  15. Quantitative NMR spectroscopy of biologically active substances and excipients

    Microsoft Academic Search

    Tanja Beyer; Bernd Diehl; Ulrike Holzgrabe

    2010-01-01

    Biologically active ingredients and excipients are the essentials of a drug formulation, such as a tablet, dragee, solution,\\u000a etc. Quality control of such substances thus plays a pivotal role in the production process of pharmaceutical drugs. Since\\u000a these agents often exhibit complex structures, consist of multiple components, or lack of a chromophore, traditional means\\u000a of characterization are often not feasible.

  16. Plants with antitumor properties: from biologically active molecules to drugs

    Microsoft Academic Search

    Ilaria Lampronti; Mahmud Tareq Hassan Khan; Nicoletta Bianchi; Elisabetta Lambertini; Roberta Piva; Monica Borgatti; Roberto Gambari

    2006-01-01

    Medicinal plants are of great interest as starting material for identification of new biologically active compounds. A large number of low-molecular-weight compounds isolated from plants or microorganisms have already been identified as effective in diseases as diverse as HIV infection, herpes simplex, neuroblastoma, and breast cancer. Some drugs that emerged from this process are already in the late-phase clinical trials.

  17. Isolation of specific cranberry flavonoids for biological activity assessment

    Microsoft Academic Search

    Ajay P. Singh; Ted Wilson; Amanda J. Kalk; James Cheong; Nicholi Vorsa

    2009-01-01

    Characterisation of cranberry compound biological activity is constrained by limitations in isolation methodology. A single rapid procedure for polyphenolic isolation was developed using semi-preparative-HPLC. Non-flavonoid compounds were removed by pre-purification procedures prior to semi-preparative-HPLC. Fractions were analysed to ascertain purity (99%) with HPLC and ESI mass spectrometric detection in negative ion mode and on-line diode array ultraviolet–visible spectroscopy. Isolated cranberry

  18. Biological soil crusts: a microenvironment characterized by complex microbial interrelations affected by the presence of the exopolysaccharidic matrix.

    NASA Astrophysics Data System (ADS)

    De Philippis, Roberto

    2015-04-01

    Biological Soil Crusts (BSCs) are complex microbial communities, commonly found in arid and semiarid areas of the world. The capability of the microorganisms residing in BSCs to withstand the harsh environmental conditions typical of these habitats, namely drought and high solar irradiation, is related with the presence of a matrix constituted by microbial-produced extracellular polysaccharides (EPSs), which also accomplish for a wide array of key ecological roles. EPSs represent a huge carbon source directly available to heterotrophic organisms, affect soil characteristics, water regimes, and establish complex interactions with plants. The induction of BSCs on degraded soils is considered a feasible approach to amend and maintain land fertility, as it was reported in a number of recent studies. It was recently shown that BSC induction is beneficial in enhancing SOC (Soil Organic Carbon) and in increasing the abundance of phototrophic organisms and vegetation cover. This lecture will describe the results of a study showing that cyanobacterial-EPS resulted advantageous to the growth and metabolism of seedlings of Caragana korshinskii, a desert sub-shrub widely diffused in the area under study, also contributing a defensive effect against the damaging effects of reactive oxygen species (ROS), generated under UV-irradiation, salt stress and desiccation. A study aimed at investigating the possible correlation between the chemical composition and the macromolecular features of the EPS matrix of induced BSCs of different age, collected in the hyper-arid plateau of Hobq desert, Inner Mongolia, China, will be also presented. The results of this study showed that the characteristics of the EPS of the matrix of the investigated IBSCs cannot be put only in relation with the age of the crusts and the activity of phototrophic microorganisms but, more properly, it has to be taken into account the biotic interactions ongoing between EPS producers (cyanobacteria, green microalgae, and microfungi as major) and consumers (e.g. microfungi, heterotrophic bacteria). Moreover, it has to be stressed that the presence of environmental stressors (i.e. soil moisture, crust coverage, and species diversity) seems to be capable of differentiating the developmental level of induced BSCs more than the biotic factors with a consequent differentiation in the characteristics of the EPS-matrix of the crusts hardly correlable with the age.

  19. Why Control Activity? Evolutionary Selection Pressures Affecting the Development of Physical Activity Genetic and Biological Regulation

    PubMed Central

    2013-01-01

    The literature strongly suggests that daily physical activity is genetically and biologically regulated. Potential identities of the responsible mechanisms are unclear, but little has been written concerning the possible evolutionary selection pressures leading to the development of genetic/biological controls of physical activity. Given the weak relationship between exercise endurance and activity levels and the differential genomic locations associated with the regulation of endurance and activity, it is probable that regulation of endurance and activity evolved separately. This hypothesis paper considers energy expenditures and duration of activity in hunter/gatherers, pretechnology farmers, and modern Western societies and considers the potential of each to selectively influence the development of activity regulation. Food availability is also considered given the known linkage of caloric restriction on physical activity as well as early data relating food oversupply to physical inactivity. Elucidating the selection pressures responsible for the genetic/biological control of activity will allow further consideration of these pressures on activity in today's society, especially the linkages between food and activity. Further, current food abundance is removing the cues for activity that were present for the first 40,000 years of human evolution, and thus future research should investigate the effects of this abundance upon the mechanisms regulating activity. PMID:24455728

  20. Effects of graphene oxides on soil enzyme activity and microbial biomass.

    PubMed

    Chung, Haegeun; Kim, Min Ji; Ko, Kwanyoung; Kim, Jae Hyeuk; Kwon, Hyun-Ah; Hong, Inpyo; Park, Nari; Lee, Seung-Wook; Kim, Woong

    2015-05-01

    Due to recent developments in nanotechnology, nanomaterials (NMs) such as graphene oxide (GO) may enter the soil environment with mostly unknown consequences. We investigated the effects of GO on soil microbial activity in a 59-day soil incubation study. For this, high-purity GO was prepared and characterized. Soils were treated with up to 1 mg GO g(-1) soil, and the changes in the activities of 1,4-?-glucosidase, cellobiohydrolase, xylosidase, 1,4-?-N-acetyl glucosaminidase, and phosphatase and microbial biomass were determined. 0.5-1 mg GO g(-1) soil lowered the activity of xylosidase, 1,4-?-N-acetyl glucosaminidase, and phosphatase by up to 50% when compared to that in the control soils up to 21 days of incubation. Microbial biomass in soils treated with GO was not significantly different from that in control soils throughout the incubation period, and the soil enzyme activity and microbial biomass were not significantly correlated in this study. Our results indicate that soil enzyme activity can be lowered by the entry of GO into soils in short term but it can be recovered afterwards. PMID:25668283

  1. Biological Soil Disinfestation (BSD), a new control method for potato brown rot, caused by Ralstonia solanacearum race 3 biovar 2

    Microsoft Academic Search

    Nevein A. S. Messiha; Anne D. van Diepeningen; Marcel Wenneker; Alexander R. van Beuningen; Jaap D. Janse; Trudie G. C. Coenen; Aad J. Termorshuizen; Ariena H. C. van Bruggen; Wim J. Blok

    2007-01-01

    The potential of Biological Soil Disinfestation (BSD) to control potato brown rot, caused by Ralstonia solanacearum race 3 biovar 2, was investigated. BSD involves the induction of anaerobic soil conditions by increasing microbial respiration\\u000a through incorporation of fresh organic amendments (here: grass or potato haulms) and by reducing re-supply of oxygen by covering\\u000a with airtight plastic sheets. Control treatments were

  2. Non-biological fixation of atmospheric nitrogen to nitrate on titanium dioxide and desert soil surfaces

    NASA Astrophysics Data System (ADS)

    Al-Taani, Ahmed A.

    Elevated nitrate levels have frequently been observed in soils and the associated groundwater in arid regions of the U.S, many of which are distant from anthropogenic sources. Although these elevated nitrate concentrations have generally been linked to atmospheric precipitation, the current study indicates that at least a portion of these nitrates may have been formed through photochemical and thermal transformation reactions on soil surfaces. Photochemical nitrogen fixation to nitrate was observed on pure TiO 2 (both anatase and rutile) and desert soil surfaces when exposed to sunlight from 2 to 80 days. The yields of nitrate were generally proportional to irradiation time and increased substantially when sodium hydroxide was added. Larger surface films of soils or TiO2 generated higher yields of nitrate. Soils with higher content of both titanium and calcium exhibit higher photoactivities, and the production rate varied slightly with particle size. Traces of nitrite and ammonia detected on irradiated TiO2 surface were similar to background levels, and are probably not intermediates in the formation of nitrate. TiO2 and soils obtained from Atacama Desert in northern Chile and Pyramid Lake, NV were irradiated with sunlight for 32 days in either 15N labeled or unlabeled nitrogen and produced nitrates enriched in 15N and that nearly all isotopic values were higher than that of atmospheric 15N. Nitrate produced photochemically on Atacama Desert soils have isotopic values that are similar to those of the subsoil nitrates of the Atacama Desert. During our experimental investigation and while preparing thin films of TiO2 by thermal evaporation of an aqueous suspension in Petri dishes, we consistently observed an increase in nitrate concentrations in all samples (even the controls) whenever TiO2 slurries came in contact with heat and air. An expanded series of experiments was carried out in a conventional oven in the absence of light; photocatalytic reactions are not involved. Nitrate was produced over the temperature range of 50-200°C following 2 hours of heating and gave yields that were linear with increases in temperature. Nitrate formation was also observed on certain arid land soils thermally treated in the normal atmosphere at 200°C for 2-50 hours or at 70°C for 15 hours or one week, although the rate of nitrate formation varied with different soils. Under the conditions employed, the yield of nitrate was a function of the area of the TiO2 or soils on the Petri dish. Formation of minor amounts of nitrite was also observed. Nitrate yields were produced in approximately equal amounts following a series of successive cycles of heating and extraction of the same soil fractions or TiO2 material indicating that the measured nitrate concentrations are not a result of soil nitrate release. Soils from Atacama Desert and Pyramid Lake have shown higher thermal activities and produced larger yields of nitrate than that measured for other soils tested. Additions of stoichiometric amounts of sodium, potassium or calcium hydroxide increased the amount of nitrate observed on both TiO 2 and on soils. Nitrates generated thermally on TiO2 or on soils from Pyramid Lake and from Atacama Desert have been enriched in 15N when heated in 5ml of 15N labeled nitrogen. The majority of d15N values of nitrate produced on TiO2 or on soil surfaces heated in air have d 15N ratios larger than that of atmospheric N. The isotopic composition of nitrate formed on heated soil surface has values similar to those observed for desert subsoil nitrates and linked to atmospheric processes. Nitrate was also detected on soils heated at 70°C suggesting that this process is likely occurring naturally on desert soils by the influence of sunlight heating. Consideration of these processes will likely raise the question on the origin of subsoil nitrate in arid and semiarid land and potentially help to explain the elevated nitrate levels observed in desert soils and groundwater which have been largely attributed to long-term atmospheric nitrate precipitation.

  3. A new biologically active flavonol glycoside from Psoralea corylifolia (Linn.).

    PubMed

    Yadava, R N; Verma, Vikash

    2005-08-01

    A new biologically active flavonol glycoside (1) mp 264-265 degrees C, C32H38O20, [M]+ 742 (EIMS) has been isolated from the methanol-soluble fraction of the defatted seeds of Psoralea corylifolia (Linn.). It was characterised as the new flavonol glycoside 3,5,3',4'-tetrahydroxy-7-methoxyflavone-3'-O-alpha-L-xylopyranosyl(1-->3)-O-alpha-L-arabinopyranosyl(1-->4)-O-beta-D-galactopyranoside by several colour reactions, spectral analysis and chemical degradations. Compound 1 showed anti-microbial activity against various bacteria and fungi. PMID:16087643

  4. Processed Vietnamese ginseng: Preliminary results in chemistry and biological activity

    PubMed Central

    Le, Thi Hong Van; Lee, Seo Young; Kim, Tae Ryong; Kim, Jae Young; Kwon, Sung Won; Nguyen, Ngoc Khoi; Park, Jeong Hill; Nguyen, Minh Duc

    2013-01-01

    Background This study was carried out to investigate the effect of the steaming process on chemical constituents, free radical scavenging activity, and antiproliferative effect of Vietnamese ginseng. Methods Samples of powdered Vietnamese ginseng were steamed at 120°C for various times and their extracts were subjected to chemical and biological studies. Results Upon steaming, contents of polar ginsenosides, such as Rb1, Rc, Rd, Re, and Rg1, were rapidly decreased, whereas less polar ginsenosides such as Rg3, Rg5, Rk1, Rk3, and Rh4 were increased as reported previously. However, ocotillol type saponins, which have no glycosyl moiety at the C-20 position, were relatively stable on steaming. The radical scavenging activity was increased continuously up to 20 h of steaming. Similarly, the antiproliferative activity against A549 lung cancer cells was also increased. Conclusion It seems that the antiproliferative activity is closely related to the contents of ginsenoside Rg3, Rg5, and Rk1. PMID:24748840

  5. Biological activities of oligoketide pigments of Monascus purpureus.

    PubMed

    Martínková, L; Patáková-J?zlová, P; Krent, V; Kucerová, Z; Havlícek, V; Olsovský, P; Hovorka, O; Ríhová, B; Veselý, D; Veselá, D; Ulrichová, J; Prikrylová, V

    1999-01-01

    Rubropunctatin (1), monascorubrin (2), monascin (3) and ankaflavin (4) were purified from the mycelium of Monascus purpureus by flash chromatography on silica gel or reversed phase. Their embryotoxicity towards chicken embryos decreased in the order 2 > 1 > 3 > 4. The lower homologues 1 and 3 exhibited teratogenic effects on these organisms. Significant antibiotic activities against Bacillus subtilis and Candida pseudotropicalis were found with compounds 1 and 2. Immunosuppressive activity on mouse T-splenocytes was most pronounced with compounds 3 and 4. None of the compounds showed significant cytotoxic activity towards rat hepatocytes in vitro. Incubation of resting cells of M. purpureus with glycine afforded the dark-red compounds 5 and 6 where the pyran moiety of 1 and 2 changed into the N-substituted dihydropyridine moiety by replacement of the O-atom by the amino group of glycine. Compounds 5 and 6 were less biologically active than the major pigments 1-4. PMID:11565571

  6. New Strategy for the Search of Natural Biologically Active Substances

    PubMed Central

    Dushenkov, V.; Raskin, I.

    2008-01-01

    The modern pharmaceutics actively screens an immense diversity of substances occurring in plants and other natural resources in the search for new effective medicinal agents. The Global Institute for Bioexploration (GIBEX) established by joint efforts of Rutgers University and the University of Illinois (United States) represents the organizational core of international scientific community whose activity is directed towards the search and development of new medicinal preparations from natural raw materials. The basis of GIBEX activity is the transfer of modern screening technologies to countries and geographical regions characterized by remarkable biodiversity. The GIBEX goals are to encourage the search for new natural biologically active substances, to maintain biodiversity, and to monitor the natural resources conservation. PMID:19578478

  7. Biologically active traditional medicinal herbs from Balochistan, Pakistan.

    PubMed

    Zaidi, Mudassir A; Crow, Sidney A

    2005-01-01

    The biological activities of the following four important medicinal plants of Balochistan, Pakistan were checked; Grewia erythraea Schwein f. (Tiliaceae), Hymenocrater sessilifolius Fisch. and C.A. Mey (Lamiaceae), Vincetoxicum stocksii Ali and Khatoon (Asclepiadaceae) and Zygophyllum fabago L. (Zygophyllaceae). The methanolic extracts were fractionated into hexane, ethyl acetate, chloroform, butanol and water. The antifungal and antibacterial activities of these plants were determined against 12 fungal and 12 bacterial strains by agar well diffusion and disk diffusion assays. The extract of Zygophyllum fabago was found to be highly effective against Candida albicans and Escherichia coli. The extract of Vincetoxicum stocksii was also found to be significantly active against Candida albicans, Bacillus subtilis and Bacillus cereus. Extracts of Hymenocrater sessilifolius and Grewia erythraea showed good activity only against Pseudomonas aeruginosa. PMID:15588685

  8. Controlled Release of Biologically Active Silver from Nanosilver Surfaces

    PubMed Central

    Liu, Jingyu; Sonshine, David A.; Shervani, Saira; Hurt, Robert H.

    2010-01-01

    Major pathways in the antibacterial activity and eukaryotic toxicity of nano-silver involve the silver cation and its soluble complexes, which are well established thiol toxicants. Through these pathways, nano-silver behaves in analogy to a drug delivery system, in which the particle contains a concentrated inventory of an active species, the ion, which is transported to and released near biological target sites. Although the importance of silver ion in the biological response to nano-silver is widely recognized, the drug delivery paradigm has not been well developed for this system, and there is significant potential to improve nano-silver technologies through controlled release formulations. This article applies elements of the drug delivery paradigm to nano-silver dissolution and presents a systematic study of chemical concepts for controlled release. After presenting thermodynamic calculations of silver species partitioning in biological media, the rates of oxidative silver dissolution are measured for nanoparticles and macroscopic foils and used to derive unified area-based release kinetics. A variety of competing chemical approaches are demonstrated for controlling the ion release rate over four orders of magnitude. Release can be systematically slowed by thiol and citrate ligand binding, formation of sulfidic coatings, or the scavenging of peroxy-intermediates. Release can be accelerated by pre-oxidation or particle size reduction, while polymer coatings with complexation sites alter the release profile by storing and release inventories of surface-bound silver. Finally, the ability to tune biological activity is demonstrated through bacterial inhibition zone assay carried out on selected formulations of controlled release nano-silver. PMID:20968290

  9. Lupine influence on soil carbon, nitrogen and microbial activity in developing ecosystems at Mount St. Helens

    Microsoft Academic Search

    J. J. Halvorson; J. L. Smith; E. H. Franz

    1991-01-01

    Lupine influence on soil C, N, and microbial activity was estimated by comparing root-zone soil (LR) to nonroot-zone soil (NR) collected at Mount St. Helens. Samples were collected from 5 sites forming a gradient of C and N levels as a reflection of different locations and varying volcanic disturbance by the 1980 eruption. In volcanic substrates undergoing primary ecosystem development,

  10. Soil microbial communities and activities in sand dunes of subtropical coastal forests

    Microsoft Academic Search

    Ed-Haun Chang; Chien-Teh Chen; Tsai-Huei Chen; Chih-Yu Chiu

    2011-01-01

    To understand the soil microbial activities and community structures in different forests in a sand-dune ecosystem, we conducted a study of 2 topographic conditions, upland and lowland, under a Casuarina forest. As well, in the lowland site, we compared forest soil microbial properties under 3 coastal forests (Casuarina, Hibiscus and mixed stand). The soil microbial biomass did not significantly differ

  11. Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities

    Microsoft Academic Search

    Feng Liu; Guang-Guo Ying; Ran Tao; Jian-Liang Zhao; Ji-Feng Yang; Lan-Feng Zhao

    2009-01-01

    The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was

  12. ECOSYSTEM ECOLOGY The effects of tree rhizodeposition on soil exoenzyme activity,

    E-print Network

    Schmidt, Steven K.

    ECOSYSTEM ECOLOGY The effects of tree rhizodeposition on soil exoenzyme activity, dissolved organic), and microbial biomass C and N. We found that rhi- zodeposition is high in the spring, when the soils are still, and organic phosphorus are not affected by springtime increases in soil microbial biomass associated

  13. Identification of Bacterial Micropredators Distinctively Active in a Soil Microbial Food Web

    Microsoft Academic Search

    Tillmann Lueders; Reimo Kindler; Anja Miltner; Michael W. Friedrich; Matthias Kaestner

    2006-01-01

    The understanding of microbial interactions and trophic networks is a prerequisite for the elucidation of the turnover and transformation of organic materials in soils. To elucidate the incorporation of biomass carbon into a soil microbial food web, we added 13C-labeled Escherichia coli biomass to an agricultural soil and identified those indigenous microbes that were specifically active in its mineralization and

  14. Effects of pyrite sludge pollution on soil enzyme activities: Ecological dose–response model

    Microsoft Academic Search

    M. Belén Hinojosa; José A. Carreira; José M. Rodríguez-Maroto; Roberto García-Ruíz

    2008-01-01

    A laboratory study was conducted to evaluate the response of soil enzyme activities (acid and alkaline phosphatase, ?-glucosidase, arylsulfatase, urease and dehydrogenase) to different levels of trace elements pollution in soils representative of the area affected by the pyrite sludge mining spill of Aznalcóllar (Guadiamar basin, SW Spain). Three uncontaminated soils from the study area were mixed with different loads

  15. SOIL AND WATER CONSERVATION PROJECTS AND ACTIVITIES, A GUIDE FOR 4-H CLUB LEADERS.

    ERIC Educational Resources Information Center

    FOSTER, ALBERT B.; FOX, ADRIAN C.

    THIS PUBLICATION WAS PREPARED BY THE SOIL CONSERVATION SERVICE FOR USE WITH YOUTH GROUPS. VARIOUS ACTIVITIES AND PROJECTS ARE PRESENTED WHICH CAN BE USED TO DEVELOP CONCEPTS ABOUT SOIL AND WATER CONSERVATION. IN ORDER TO SIMPLIFY THE PROCESS OF DEMONSTRATING THESE ACTIVITIES, MANY OF THE CONCEPTS ARE PICTORIALLY ILLUSTRATED. THE ACTIVITIES

  16. Estimating soil resilience to a toxic organic waste by measuring enzyme activities

    Microsoft Academic Search

    Emilio Benitez; Raquel Melgar; Rogelio Nogales

    2004-01-01

    The ability of a degraded soil to respond to successive additions of a toxic organic waste (olive-mill solid waste) and its vermicompost was studied in a controlled incubation experiment for 32 weeks. Hydrolytic enzyme activities (phosphatase, ?-glucosidase), oxidoreductase activities (dehydrogenase, o-diphenol oxidase) and indole acetic acid production, were used as measures of soil perturbation. No microbial activity, indicated by the

  17. The multiple nutrition properties of some exotic fruits: Biological activity and active metabolites

    Microsoft Academic Search

    Valery M. Dembitsky; Sumitra Poovarodom; Hanna Leontowicz; Maria Leontowicz; Suchada Vearasilp; Simon Trakhtenberg; Shela Gorinstein

    2011-01-01

    The main objective of this review was to describe the physicochemical and nutritional characteristics of twenty selected exotic fruits and the influence of their physiologically active compounds on human health, through scientifically proven information. The review presents the biologically active metabolites derived from exotic fruits (polyphenols, flavonoids, flavanols, tannins, ascorbic acid, anthocyanins, volatile compounds, minerals, and organic acids) and various

  18. Depth stratification of soil organic matter as an indicator of multiple ecosystem services

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic matter is a key component of soil quality that sustains many key soil functions by providing the energy, substrates, and biological diversity to support biological activity, which affects aggregation (important for habitat space, oxygen supply, and preventing soil erosion), infiltration...

  19. STRATIFICATION OF SOIL ORGANIC MATTER AND POTENTIAL IMPACT ON WATER RUNOFF QUALITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic matter is a key component of soil quality that sustains many key soil functions by providing the energy, substrates, and biological diversity to support biological activity, which affects (1) aggregation (important for habitat space, oxygen supply, and preventing soil erosion), infiltra...

  20. Effect of pyrene and cadmium on microbial activity and community structure in soil.

    PubMed

    Lu, Mang; Xu, Kui; Chen, Jun

    2013-04-01

    In this study, a greenhouse experiment was conducted to investigate interactive effects of cadmium (Cd) × pyrene × plant treatments on soil microbial activity and community structure. The results demonstrated that the basal respiration, microbial biomass carbon and metabolic quotient in both unplanted and rhizosphere soil were significantly influenced by interaction of Cd and pyrene. The combined application of Cd and pyrene caused a significantly greater biocidal influence on the soil microorganisms than the single spiking of Cd or pyrene. The soil basal respiration increased with the spiking of 2.5 mg kg(-1) Cd in both unplanted and rhizosphere soil. The eco-physiological index of Cd-tolerant populations was significantly different among the unplanted soil, rhizoplane and rhizosphere soil of tall fescue, indicating a slightly uneven distribution of fast- and slow-growing tolerant bacteria. Obvious differences in microbial activity were observed among treatments due to different physicochemical characteristics of the rhizosphere soils depending on the plant species. PMID:23290945

  1. Does powder and granular activated carbon perform equally in immobilizing chlorobenzenes in soil?

    PubMed

    Song, Yang; Wang, Fang; Kengara, Fredrick Orori; Bian, Yongrong; Yang, Xinglun; Gu, Chenggang; Ye, Mao; Jiang, Xin

    2015-01-01

    The objective of this study is to compare the efficacies of powder activated carbon (PAC) and granular activated carbon (GAC) as amendments for the immobilization of volatile compounds in soil. Soil artificially-spiked with chlorobenzenes (CBs) was amended with either PAC or GAC to obtain an application rate of 1%. The results showed that the dissipation and volatilization of CBs from the amended soil significantly decreased compared to the unamended soil. The bioavailabilities of CBs, which is expressed as butanol extraction and earthworm accumulation, were significantly reduced in PAC and GAC amended soils. The lower chlorinated and hence more volatile CBs experienced higher reductions in both dissipation and bioavailability in the amended soils. The GAC and PAC equally immobilized more volatile CBs in soil. Therefore, it could be concluded that along with environmental implication, applying GAC was the more promising approach for the effective immobilization of volatile compounds in soil. PMID:25406989

  2. Degradation of biochemical activity in soil sterilized by dry heat and gamma radiation

    NASA Technical Reports Server (NTRS)

    Shih, K. L.; Souza, K. A.

    1978-01-01

    The effect of soil sterilization by dry heat (0.08% relative humidity), gamma radiation, or both on soil phosphatase, urease, and decarboxylase activity was studied. Soil sterilized by a long exposure to dry heat at relatively low temperatures (eight weeks at 100.5 C) retained higher activities than did soil exposed to a higher temperature (two weeks at 124.5 C), while all activity was destroyed by four days at 148.5 C. Sterilization with 7.5 Mrads destroyed less activity than did heat sterilization. The effect of several individually nonsterizing doses of heat radiation is described.

  3. Biological soil crusts are the main contributor to winter soil respiration in a temperate desert ecosystem of China

    NASA Astrophysics Data System (ADS)

    He, M. Z.

    2012-04-01

    Aims Biological soil crusts (BSCs) are a key biotic component of desert ecosystems worldwide. However, most studies carried out to date on carbon (fluxes) in these ecosystems, such as soil respiration (RS), have neglected them. Also, winter RS is reported to be a significant component of annual carbon budget in other ecosystems, however, we have less knowledge about winter RS of BSCs in winter and its contribution to carbon cycle in desert regions. Therefore, the specific objectives of this study were to: (i) quantify the effects of different BSCs types (moss crust, algae crust, physical crust) on the winter RS; (ii) explore relationships of RS against soil temperature and water content for different BSCs, and (iii) assess the relative contribution of BSCs to the annual amount of C released by RS at desert ecosystem level. Methods Site Description The study sites are located at the southeast fringe of the Tengger Desert in the Shapotou region of the Ningxia Hui Autonomous Region [37°32'N and 105°02'E, at 1340 m above mean sea level (a.m.s.l.)], western China. The mean daily temperature in January is -6.9°C , while it is 24.3°C in July. The mean annual precipitation is 186 mm, approximately 80% of which falls between May and September. The annual potential evaporation is 2800 mm. The landscape of the Shapotou region is characterized by large and dense reticulate barchans chains of sand dunes that migrate south-eastward at a velocity of 3-6 m per year. The soil is loose, infertile and mobile and can thus be classified as orthic sierozem and Aeolian sandy soil. Additionally, the soil has a consistent gravimetric water content that ranges from 3 to 4%. The groundwater in the study area is too deep (>60 m) to support large areas of the native vegetation cover; therefore, precipitation is usually the only source of freshwater. The predominant native plants are Hedysarum scoparium Fisch. and Agriophyllum squarrosum Moq., Psammochloa cillosa Bor, which scattered distribute with cover about 1% of the entire study area. Prior to revegetation, straw-checkerboards approximately 1×1 m2 in area were constructed using wheat or rice straw to stabilize the dune surface and allow time for the planted xerophytic shrubs to adapt to the new environment. In 1956, the following 2-year-old xerophytic shrub seedlings were planted within the checkerboard at a density of 16 individuals per 100 m2 and grown without irrigation: Artemisia ordosica Krasch, H. scoparium Fisch, Calligonum mongolicum Turc'z, Caragana microphylla Lam., Caragana korshinskii Kom, Salix gordejevii and Atraphaxis bracteata A.Los. The stabilized area was then expanded to parallel areas in 1964 and 1982 using the same method and species. As a result, the initial stages of change that have occurred at these sites were similar. After more than fifties years succession, the predominant plants are semi-shrubs, shrubs, forbs, and grasses at present and BSCs formed. The common BSCs in the region may be dominated by cyanobacteria, algae, lichens and mosses, or any combination of these organisms. Cyanobacteria species include Microcolous vaginatus Gom., Hydrocoleus violacens Gom., Lyngbya crytoraginatus Schk., Phormidium amblgum Gom., P. autumnale (Ag.) Gom., P. foveolarum (Mont.) Gom. and Phormidium luridum (Kutz) Gom. etc; algal species mainly include Anabaena azotica Ley, Euglena sp., Hantzschia amphioxys var capitata Grum, Oscillatoria obscura Gom., O. pseudogeminate G. Schm. And Scytonema javanicum (Kutz) Bornet Flash etc; lichen species include Collema tenax (Sw.) Ach., Endocarpon pusillum Hedw.; and moss species are dominated by Bryum argenteum Hedw., Didymodon constrictus (Mitt.) Saito., Tortula bidentata Bai Xue Liang and T. desertorum Broth.. Experimental Design and Rs measurements On October 2010, We selected the moss-dominated BSCs at four revegetation sites and natural vegetation sites, in which 3 replicated plots were selected randomly. In each plot, olyvinyl chloride (PVC) collar (lenth 10 cm, internal diameter 10cm ) were inserted 7 cm into the soil. During the

  4. Soil microbial biomass nitrogen and Beta-Glucosaminidase activity response to compaction, poultry litter application and cropping in a claypan soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Compaction-induced changes in soil physical properties may significantly affect soil microbial activity, especially nitrogen-cycling processes, in many agroecosystems. The objective of this study was to determine the effect of soil compaction on soil microbiological properties related to N in a clay...

  5. Impacts of chemical amendment and plant growth on lead speciation and enzyme activities in a shooting range soil: an x-ray absorption fine structure investigation.

    PubMed

    Hashimoto, Yohey; Matsufuru, Hiroki; Takaoka, Masaki; Tanida, Hajime; Sato, Takeshi

    2009-01-01

    In situ chemical immobilization is a practical remediation technology for metal-contaminated soils because of its capability to reduce cost and environmental impacts. We assessed the immobilization effects of poultry waste amendment and plant growth (Panicum maximum Jacq.) on Pb speciation and enzyme activities in shooting range soils. Soil contaminated with Pb was obtained from the top 20 cm of a shooting range. To evaluate Pb mobility in the soil profile treated with plants and immobilizing amendment, we used large columns filled with Pb-contaminated soil (0-20 cm, surface soils) and non-contaminated soil (20-75 cm, subsurface soils). The column study demonstrated that the amendment reduced the toxicity characteristic leaching procedure-extractable Pb in the surface soil by 90% of the Control soil. Lead mobility from the surface to subsurface profiles was significantly attenuated by plant growth but was promoted by the amendment without plant application. The extended X-ray absorption fine structure analysis revealed that the amendment reduced the proportion of PbCO(3) and Pb-organic complexes and transformed them into a more geochemically stable species of Pb(5)(PO(4))(3)Cl with 30 to 35% of the total Pb species. Applications of plant and amendment increased activities of dehydrogenase and phosphatase in the surface soil with 2.7- and 1.1-fold greater than those in Control, respectively. The use of amendments in combination with plant growth may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils. PMID:19465717

  6. Soil Biology & Biochemistry 40 (2008) 986994 Potential fluxes of N2O and CH4 from soils of three forest

    E-print Network

    Moore, Tim

    2008-01-01

    types in Eastern Canada. Soil samples collected from deciduous, black spruce and white pine forests were-response to mineral N additions. Soils in deciduous, boreal and white pine forests consumed CH4 when incubated under an elevated headspace CH4 concentration, except the poorly drained soils in the deciduous forest, which

  7. Nonanolides of natural origin: structure, synthesis, and biological activity.

    PubMed

    Sun, P; Lu, S; Ree, T V; Krohn, K; Li, L; Zhang, W

    2012-01-01

    Naturally occurring nonanolides (synonym decanolides) are a large family of secondary metabolites with an interesting 10- membered macrolide subunit. Metabolites of the nonanolide family have been found to have various biological activities, including cytotoxic, phytotoxic, antimalarial, antifungal, antibacterial, and antimicrofilament activities. An early review of the chemistry and bioactivity of nonanolides was presented in 1996, covering the literature published between 1975 and 1995. During the past decades, the broad spectrum of bioactivity and the intriguing structure of the medium-sized ring in nonanolide analogues have continuously drawn the attention of biologists and natural product and synthetic chemists, resulting in a great number of publications. This review summarizes in whole the recent progress in the field of the nonanolides of natural origin, aiming to give the readers a brief view of the compounds, concerning their natural occurrence, structural elucidation, biological activities, total synthesis, and structure-activity relationships. The article covers the literature published in the period from the beginning of 1996 to July 2011. PMID:22612710

  8. Application of activation techniques to biological analysis. [813 references

    SciTech Connect

    Bowen, H.J.M.

    1981-12-01

    Applications of activation analysis in the biological sciences are reviewed for the period of 1970 to 1979. The stages and characteristics of activation analysis are described, and its advantages and disadvantages enumerated. Most applications involve activation by thermal neutrons followed by either radiochemical or instrumental determination. Relatively little use has been made of activation by fast neutrons, photons, or charged particles. In vivo analyses are included, but those based on prompt gamma or x-ray emission are not. Major applications include studies of reference materials, and the elemental analysis of plants, marine biota, animal and human tissues, diets, and excreta. Relatively little use of it has been made in biochemistry, microbiology, and entomology, but it has become important in toxicology and environmental science. The elements most often determined are Ag, As, Au, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, Mn, Mo, Na, Rb, Sb, Sc, Se, and Zn, while few or no determinations of B, Be, Bi, Ga, Gd, Ge, H, In, Ir, Li, Nd, Os, Pd, Pr, Pt, Re, Rh, Ru, Te, Tl, or Y have been made in biological materials.

  9. Biologically Active Metabolites Produced by the Basidiomycete Quambalaria cyanescens

    PubMed Central

    Stod?lková, Eva; Císa?ová, Ivana; Kola?ík, Miroslav; Chudí?ková, Milada; Novák, Petr; Man, Petr; Kuzma, Marek; Pavl?, Barbora; ?erný, Jan; Flieger, Miroslav

    2015-01-01

    Four strains of the fungus Quambalaria cyanescens (Basidiomycota: Microstromatales), were used for the determination of secondary metabolites production and their antimicrobial and biological activities. A new naphthoquinone named quambalarine A, (S)-(+)-3-(5-ethyl-tetrahydrofuran-2-yliden)-5,7,8-trihydroxy-2-oxo-1,4-naphthoquinone (1), together with two known naphthoquinones, 3-hexanoyl-2,5,7,8-tetrahydroxy-1,4-naphthoquinone (named here as quambalarine B, 2) and mompain, 2,5,7,8-tetrahydroxy-1,4-naphthoquinone (3) were isolated. Their structures were determined by single-crystal X-ray diffraction crystallography, NMR and MS spectrometry. Quambalarine A (1) had a broad antifungal and antibacterial activity and is able inhibit growth of human pathogenic fungus Aspergillus fumigatus and fungi co-occurring with Q. cyanescens in bark beetle galleries including insect pathogenic species Beauveria bassiana. Quambalarine B (2) was active against several fungi and mompain mainly against bacteria. The biological activity against human-derived cell lines was selective towards mitochondria (2 and 3); after long-term incubation with 2, mitochondria were undetectable using a mitochondrial probe. A similar effect on mitochondria was observed also for environmental competitors of Q. cyanescens from the genus Geosmithia. PMID:25723150

  10. Biologically active metabolites produced by the basidiomycete Quambalaria cyanescens.

    PubMed

    Stod?lková, Eva; Císa?ová, Ivana; Kola?ík, Miroslav; Chudí?ková, Milada; Novák, Petr; Man, Petr; Kuzma, Marek; Pavl?, Barbora; ?erný, Jan; Flieger, Miroslav

    2015-01-01

    Four strains of the fungus Quambalaria cyanescens (Basidiomycota: Microstromatales), were used for the determination of secondary metabolites production and their antimicrobial and biological activities. A new naphthoquinone named quambalarine A, (S)-(+)-3-(5-ethyl-tetrahydrofuran-2-yliden)-5,7,8-trihydroxy-2-oxo-1,4-naphthoquinone (1), together with two known naphthoquinones, 3-hexanoyl-2,5,7,8-tetrahydroxy-1,4-naphthoquinone (named here as quambalarine B, 2) and mompain, 2,5,7,8-tetrahydroxy-1,4-naphthoquinone (3) were isolated. Their structures were determined by single-crystal X-ray diffraction crystallography, NMR and MS spectrometry. Quambalarine A (1) had a broad antifungal and antibacterial activity and is able inhibit growth of human pathogenic fungus Aspergillus fumigatus and fungi co-occurring with Q. cyanescens in bark beetle galleries including insect pathogenic species Beauveria bassiana. Quambalarine B (2) was active against several fungi and mompain mainly against bacteria. The biological activity against human-derived cell lines was selective towards mitochondria (2 and 3); after long-term incubation with 2, mitochondria were undetectable using a mitochondrial probe. A similar effect on mitochondria was observed also for environmental competitors of Q. cyanescens from the genus Geosmithia. PMID:25723150

  11. Combined effects of bacterial-feeding nematodes and prometryne on the soil microbial activity

    Microsoft Academic Search

    Jihai Zhou; Xuechao Li; Ying Jiang; Yue Wu; Jiandong Chen; Feng Hu; Huixin Li

    2011-01-01

    Microcosm experiments were carried out to study the effects of bacterial-feeding nematodes and indigenous microbes and their interactions on the degradation of prometryne and soil microbial activity in contaminated soil. The results showed that soil indigenous microbes could degrade prometryne up to 59.6–67.9%; bacterial-feeding nematodes accelerated the degradation of prometryne in contaminated soil, and prometryne degradation was raised by 8.36–10.69%.

  12. Active microwave remote sensing for soil moisture measurement: a field evaluation using ERS-2

    Microsoft Academic Search

    Jeffrey P. Walker; Paul R. Houser; Garry R. Willgoose

    2003-01-01

    Active microwave remote sensing observations of backscattering, such as C-band vertically polarized synthetic aperture radar (SAR) observations from the second European remote sensing (ERS-2) satellite, have the potential to measure moisture content in a near-surface layer of soil. However, SAR backscattering observations are highly dependent on topography, soil texture, surface roughness and soil moisture, meaning that soil moisture inversion from

  13. Secondary successions of biota in oil-polluted peat soil upon different biological remediation methods

    NASA Astrophysics Data System (ADS)

    Melekhina, E. N.; Markarova, M. Yu.; Shchemelinina, T. N.; Anchugova, E. M.; Kanev, V. A.

    2015-06-01

    The effects of different bioremediation methods on restoration of the oil-polluted peat soil (Histosol) in the northernmost taiga subzone of European Russia was studied. The population dynamics of microorganisms belonging to different trophic groups (hydrocarbon-oxidizing, ammonifying, nitrifying, and oligonitrophilic) were analyzed together with data on the soil enzyme (catalase and dehydrogenase) activities, population densities of soil microfauna groups, their structures, and states of phytocenoses during a sevenyear-long succession. The remediation with biopreparations Roder composed of oil-oxidizing microorganisms-Roder with Rhodococcus rubber and R. erythropolis and Universal with Rhodotorula glutinis and Rhodococcus sp.-was more efficient than the agrochemical and technical remediation. It was concluded that the biopreparations activate microbiological oil destruction, thereby accelerating restoration succession of phytocenosis and zoocenosis. The succession of dominant microfauna groups was observed: the dipteran larvae and Mesostigmata mites predominant at the early stages were replaced by collembolans at later stages. The pioneer oribatid mite species were Tectocepheus velatus, Oppiella nova, Liochthonius sellnicki, Oribatula tibialis, and Eupelops sp.

  14. Enzyme activity in terrestrial soil in relation to exploration of the Martian surface

    NASA Technical Reports Server (NTRS)

    Ardakani, M. S.; Mclaren, A. D.; Pukite, A. H.

    1972-01-01

    An exploration was made of enzyme activities in soil, including abundance, persistence and localization of these activities. An attempt was made to develop procedures for the detection and assaying of enzymes in soils suitable for presumptive tests for life in planetary soils. A suitable extraction procedure for soil enzymes was developed and measurements were made of activities in extracts in order to study how urease is complexed in soil organic matter. Mathematical models were developed, based on enzyme action and microbial growth in soil, for rates of oxidation of nitrogen as nitrogen compounds are moved downward in soil by water flow. These biogeochemical models should be applicable to any percolating system, with suitable modification for special features, such as oxygen concetrations, and types of hydrodynamic flow.

  15. Soil

    NSDL National Science Digital Library

    Scott Bauer (USDA-ARS; )

    2006-05-23

    Soil is an example of a non-living thing. Soil contains nutrients and living organisms, but the soil itself is not alive. Soil is important in plant growth because soil gives plants a place to anchor their roots and it also provides the plant with essential nutrients.

  16. [Changes of microbial biomass carbon and enzyme activities in rice-barnyard grass coexisted soils].

    PubMed

    Li, Hai-Bo; Kong, Chui-Hua

    2008-10-01

    Taking barnyard grass (Echinochloa crus-galli), allelopathic rice (Oryza sativa) PI312777, and non-allelopathic rice Liaojing-9 as test materials, this paper studied the changes of microbial biomass C and of dehydrogenase, urease and invertase activities in soils under 1 : 1 rice-barnyard grass coexistence. The results showed that with the coexistence of barnyard grass, the microbial biomass C in rhizosphere soil of PI312777 was decreased by 50.52% (P < 0.01), while that in inter-row soil was increased. The microbial biomass C in rhizosphere soil of Liaojing-9 was also decreased by 38.99% (P < 0.01), but no significant difference was observed in inter-row soil. The dehydrogenase activity in rhizosphere soils of the two rice varieties were decreased by 20% or more (P < 0.05), but the urease and invertase activities in rhizosphere soil of PI312777 were significantly stimulated (P < 0.01). The invertase activity in rhizosphere soil of Liaojing-9 was inhibited by coexisting barnyard grass, but urease activity had less change. As a result, the allelopathic traits of rice variety led to a significant decrease of microbial biomass C and an increase of urease and invertase activities in rhizosphere soil under barnyard grass coexistence, implying that soil microbial biomass and enzymes might play essential roles in species interactions between rice and barnyard grass, and allelopathic rice had its advantage in resistance to barnyard grass. PMID:19123361

  17. Bacterial community dynamics over successional stages of Australian biological soil crusts

    NASA Astrophysics Data System (ADS)

    Chilton, Angela; Woodhouse, Jason; Neilan, Brett

    2015-04-01

    A key aspect for successful ecological rehabilitation is understanding the naturally occurring ecosystem and landscape function which is to be restored. This allows for recovery indicators to be identified and criteria to be developed to assess progress and outcomes. In arid rangelands, environmental stresses result in characteristically heterogeneous landscapes where biological soil crusts (BSCs) cover large expanses of inter-plant areas. Here, BSCs perform crucial roles in nutrient cycling and re-distribution, affect hydrological patterns and stabilise the soil surface. They also serve as a large reservoir of microbial and avascular plant biodiversity. The recognition of these important roles has resulted in increased global arid rehabilitation efforts employing BSCs. Within Australia, research has focused on the macro components of BSCs including lichens and mosses, however, there have been insufficient studies examining the BSC bacterial communities and their dynamics over different successional stages. This project surveyed the bacterial community of crust-free soil and three successional stages of undisturbed BSCs from New South Wales (NSW), Australia, in order to provide reference standards of naturally occurring Australian BSCs. Visual assessments were conducted and BSCs were categorised as Early, Mid or Late stage depending on colour, thickness, topography and presence of lichens and mosses. The crust-free soil and different stages were sampled within three 50 m2 plots of the same edaphic conditions near the town of Cobar, NSW. High throughput sequencing using the Illumina MiSeq platform was performed targeting the V2 region of the 16S rRNA gene. Preliminary analysis has revealed a clear distinction between the crust-free and crusted soil while Canonical Analysis of Principal Co-ordinates (CAP) suggests the presence of two distinct BSC microbial communities despite three stages being sampled. Across all sample types, the dominant phyla were Actinobacteria, Cyanobacteria and Proteobacteria. Further analysis will determine indicator species which may be used to track the recovery of Australian BSCs in disturbed lands as well as identify pioneer genera as candidate organisms for inoculum based rehabilitation trials. It is important for BSC research to continue in order to adequately direct rehabilitation efforts and for disturbed arid lands to return to self-sustaining ecosystems.

  18. Biological activities of aqueous extract from Cinnamomum porrectum

    NASA Astrophysics Data System (ADS)

    Farah, H. Siti; Nazlina, I.; Yaacob, W. A.

    2013-11-01

    A study was carried out to evaluate biological activities of an extract obtained from Cinnamomum porrectum under reflux using water. Aqueous extract of Cinnamomum porrectum was tested for antibacterial activity against six Gram-positive and eight Gram-negative bacteria as well as MRSA. The results confirmed that the aqueous extract of Cinnamomum porrectum was bactericidal. Cytotoxic tests on Vero cell culture revealed that Cinnamomum porrectum was non-toxic which IC50 value higher than 0.02 mg/mL. Antiviral activity was tested based on the above IC50 values together with the measured EC50 values to obtain Therapeutic Index. The result showed that Cinnamomum porrectum has the ability to inhibit viral replication of HSV-1 in Vero cells.

  19. Biological degradation of triclocarban and triclosan in a soil under aerobic and anaerobic conditions and comparison with environmental fate modelling

    Microsoft Academic Search

    Guang-Guo Ying; Xiang-Yang Yu; Rai S. Kookana

    2007-01-01

    Triclocarban and triclosan are two antimicrobial agents widely used in many personal care products. Their biodegradation behaviour in soil was investigated by laboratory degradation experiments and environmental fate modelling. Quantitative structure–activity relationship (QSAR) analyses showed that triclocarban and triclosan had a tendency to partition into soil or sediment in the environment. Fate modelling suggests that either triclocarban or triclosan “does

  20. The role of macrosymbiont genotypes and earthworms in the enrichment of soil with biological nitrogen

    NASA Astrophysics Data System (ADS)

    Nazaryuk, V. M.; Kalimullina, F. R.; Klenova, M. I.

    2010-06-01

    The specific features of the symbiotic apparatus and the accumulation of the plant biomass under the influence of different genotypes of peas ( Pisum sativum L.) on gray forest soils were studied in field conditions. With the alternation of legume and grass cultures, the genotypes of plants with supernodulation were found to affect the microbial nitrogen content in the soil to a greater extent than the concentration of ammonium and nitrate nitrogen. For the growing period, the N content in the microbial biomass increased, on the average, by 1.3 to 1.5 times. The consumption of nitrogen by the plants of the supernodular mutant K-301a was found to be 2.6 and 3.0 times greater than that by the pea plants of the Ramonskii-77 variety and of the K-562a line, respectively. During the after effect of the symbiotically bound air nitrogen, a significant uptake of this element was observed only by the oat plants grown after the K-56 2a. The nitrogen fixation by these plants was 1.3 times more active than that by the peas of the Ramonskii-77 variety. The importance of earthworms (Lumbricidae) and plant residues of different genotypes for the processes of mineralization of organic compounds and accumulation of ammonium, nitrate, and microbial nitrogen in the soils under optimal hydrothermal conditions was revealed. In the experiment, two maximums of the CO2 emission were recorded; they may be related to the periodic production of organic mass by the earthworms and the creation of favorable conditions for microbial activity by them. The accumulation of nitrate nitrogen (up to 150 mg/kg) in the soil was the greatest owing to the interaction between the earthworms and the residues of the supernodular K-301a mutant.

  1. Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes.

    PubMed

    González, Aileen; Díaz, Raúl; Díaz, Manuel; Borrero, Yainais; Bruzón, Rosa Y; Carreras, Bertha; Gato, René

    2011-09-01

    Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis). All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec's isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba. PMID:22017108

  2. A Stepwise Procedure for Assessment of the Microbial Respiratory Activity of Soil Samples Contaminated with Organic Compounds

    Microsoft Academic Search

    Adolf Eisentraeger; Gudrun Maxam; Jean-Paul Rila; Wolfgang Dott

    2000-01-01

    Soil respiration measurements are used frequently for the characterization of soil samples. Identical methods are used for the ecotoxicological characterization of contaminated soil samples as well as for quantification of the active microbial biomass in agriculturally used soils. In this study four soil samples contaminated with large amounts of volatile organic compounds, polyaromatic hydrocarbons, or nitroaromatic compounds are characterized after

  3. Draft Genome Sequence of Microvirga sp. Strain BSC39, Isolated from Biological Soil Crust of Moab, Utah.

    PubMed

    Bailey, Alexis C; Kellom, Matthew; Poret-Peterson, Amisha T; Noonan, Kathryn; Hartnett, Hilairy E; Raymond, Jason

    2014-01-01

    Microvirga sp. BSC39 was isolated from a biological soil crust near Moab, Utah. The strain appears to be capable of chemotaxis and exopolysaccharide synthesis for biofilm adhesion. The BSC39 genome contains iron siderophore uptake and hydrolysis enzymes; however, it lacks siderophore synthesis pathways, suggesting the uptake of siderophores produced by neighboring microbes. PMID:25395650

  4. Draft Genome Sequence of Massilia sp. Strain BSC265, Isolated from Biological Soil Crust of Moab, Utah.

    PubMed

    Bailey, Alexis C; Kellom, Matthew; Poret-Peterson, Amisha T; Noonan, Kathryn; Hartnett, Hilairy E; Raymond, Jason

    2014-01-01

    Massilia sp. BSC265 was isolated from a biological soil crust near Moab, Utah. The strain appears to be capable of chemotaxis and exopolysaccharide synthesis for biofilm adhesion. The BSC265 genome contains a complete dissimilatory nitrate reduction pathway as well as a TCA cycle, making it a facultative anaerobe. PMID:25395652

  5. Draft Genome Sequence of Bacillus sp. Strain BSC154, Isolated from Biological Soil Crust of Moab, Utah.

    PubMed

    Bailey, Alexis C; Kellom, Matthew; Poret-Peterson, Amisha T; Noonan, Kathryn; Hartnett, Hilairy E; Raymond, Jason

    2014-01-01

    Bacillus sp. BSC154 was isolated from a biological soil crust near Moab, Utah. The strain appears to be capable of chemotaxis and biofilm production. The BSC154 genome contains iron siderophore production, nitrate reduction, mixed acid-butanediol fermentation, and assimilatory and dissimilatory sulfate metabolism pathways. PMID:25395651

  6. Impacts of insect biological control on soil N transformations in Tamarix-invaded ecosystems in the Great Basin, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the impacts of insect biological control of Tamarix spp. on soil nitrogen (N) transformations is important because changes to N supply could alter plant community succession. We investigated short-term and longer-term impacts of herbivory by the northern tamarisk beetle (Diorhabda cari...

  7. Impacts of insect biological control on soil N transformations in Tamarix-invaded ecosystems in the Great Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the impacts of insect biological control of Tamarix spp. on soil nitrogen (N) transformations is important because changes to N supply could alter plant community succession. We investigated short-term and longer-term impacts of herbivory by the northern tamarisk beetle (Diorhabda cari...

  8. Propolis volatile compounds: chemical diversity and biological activity: a review

    PubMed Central

    2014-01-01

    Propolis is a sticky material collected by bees from plants, and used in the hive as building material and defensive substance. It has been popular as a remedy in Europe since ancient times. Nowadays, propolis use in over-the-counter preparations, “bio”-cosmetics and functional foods, etc., increases. Volatile compounds are found in low concentrations in propolis, but their aroma and significant biological activity make them important for propolis characterisation. Propolis is a plant-derived product: its chemical composition depends on the local flora at the site of collection, thus it offers a significant chemical diversity. The role of propolis volatiles in identification of its plant origin is discussed. The available data about chemical composition of propolis volatiles from different geographic regions are reviewed, demonstrating significant chemical variability. The contribution of volatiles and their constituents to the biological activities of propolis is considered. Future perspectives in research on propolis volatiles are outlined, especially in studying activities other than antimicrobial. PMID:24812573

  9. Biological monitoring for mercury within a community with soil and fish contamination.

    PubMed Central

    Harnly, M; Seidel, S; Rojas, P; Fornes, R; Flessel, P; Smith, D; Kreutzer, R; Goldman, L

    1997-01-01

    To assess the impact of elevated levels of inorganic mercury in soil and dust and organic mercury in fish, biological monitoring was conducted among Native Americans living next to an inactive mercury mine in Clear Lake, California. Of resident tribal members, 46% (n = 56) participated in biomonitoring. Urine mercury levels are equivalent to background, indicating that soil and dust exposures among study participants are not substantial. The average blood organic mercury level among study participants is 15.6 +/- 8.8 micrograms/l (n = 44), which is higher than levels reported by others among those who do not consume fish (2 micrograms/l). Consistent with results from other studies, a correlation between fish consumption and blood organic mercury is observed (p = 0.03). The margin between observed and established adverse effect levels for adults is examined for blood organic mercury and found to be less than 10-fold for 20% of the study population. Protective public health efforts for the study population and other similarly exposed populations, notably those who consume commercial fish products, are considered. Images Figure 1. PMID:9189708

  10. Inclusion of soil arsenic bioaccessibility in ecological risk assessment and comparison with biological effects.

    PubMed

    Saunders, Jared R; Knopper, Loren D; Koch, Iris; Reimer, Kenneth J

    2011-12-15

    The purpose of this study was to conduct an ecological risk assessment (ERA) for meadow voles (Microtus pennslvanicus) found at three arsenic contaminated sites in Nova Scotia, Canada (as well as two background locations) and to compare the numeric results to measured biomarkers of exposure and effect. The daily intake of arsenic by meadow voles was determined by three separate calculations: estimated daily intake (EDI), bioaccessible estimated daily intake (BEDI, with bioaccessibility of soil included), and actual daily intake (ADI, which is calculated with arsenic concentrations in the stomach contents). The median bioaccessibility of arsenic in soils from the contaminated locations was significantly greater than at background locations. The bioaccessible arsenic concentration in soil from all samples (both contaminated and background) was significantly less than the total concentration. Use of site-specific bioaccessibility (hazard quotients=38 at Upper Seal Harbour (USH); 60 at Lower Seal Harbour (LSH); and 120 at Montague tailings (MONT)) and stomach arsenic contents (hazard quotients=2.1 at USH; 7.9 at LSH; and 6.7 at MONT) in the ERA resulted in lower numeric risk than compared to risk calculated with 100% bioavailability (hazard quotient=180 at USH; 75 at LSH; and 680 at MONT). Further, the use of bioaccessibility on the calculation of risk was aligned with biomarker results (changes in glutathione and micronucleated erythrocytes) in voles captured at the sites. This study provides evidence that using site-specific bioaccessibility in ERAs may provide a more realistic level of conservatism, thereby enhancing the accuracy of predicting risk to wildlife receptors. Furthermore, when numeric risk assessments are combined with site-specific biological data (i.e., biomarkers of exposure and effect), both lines of evidence can be used to make informed decisions about ecological risk and site management. PMID:22078367

  11. Molecular biological access to the chemistry of unknown soil microbes: a new frontier for natural products

    Microsoft Academic Search

    Jo Handelsman; Michelle R. Rondon; Sean F. Brady; Jon Clardy; Robert M. Goodman

    1998-01-01

    Cultured soil microorganisms have provided a rich source of natural-product chemistry. Because only a tiny fraction of soil microbes from soil are readily cultured, soil might be the greatest untapped resource for novel chemistry. The concept of cloning the metagenome to access the collective genomes and the biosynthetic machinery of soil microflora is explored here.

  12. Structural role of Fe in the soil active glasses

    NASA Astrophysics Data System (ADS)

    Wac?awska, I.; Szumera, M.; Stoch, P.; Sitarz, M.

    2011-08-01

    Glasses of the SiO 2-P 2O 5-K 2O-MgO-CaO-Fe 2O 3 system acting as slow release fertilizers were synthesized by the melt-quenching technique. The influence of iron addition on the structure of glasses was evaluated by FTIR spectroscopy (with spectra decomposition) and 57Fe Mössbauer spectroscopy. The chemical activity of glasses in the 2 mass% citric acid solutions was measured by the ICP-AES method. It has been found that the formation of domains with structure similar to phosphates with chemically stable P-O-Fe 3+ and P-O-Fe 2+ bonds decreases the glass solubility under conditions simulating the soil environment.

  13. Structural role of Fe in the soil active glasses.

    PubMed

    Wac?awska, I; Szumera, M; Stoch, P; Sitarz, M

    2011-08-15

    Glasses of the SiO(2)-P(2)O(5)-K(2)O-MgO-CaO-Fe(2)O(3) system acting as slow release fertilizers were synthesized by the melt-quenching technique. The influence of iron addition on the structure of glasses was evaluated by FTIR spectroscopy (with spectra decomposition) and (57)Fe Mössbauer spectroscopy. The chemical activity of glasses in the 2 mass% citric acid solutions was measured by the ICP-AES method. It has been found that the formation of domains with structure similar to phosphates with chemically stable P-O-Fe(3+) and P-O-Fe(2+) bonds decreases the glass solubility under conditions simulating the soil environment. PMID:20875769

  14. The practicalities and pitfalls of establishing a policy-relevant and cost-effective soil biological monitoring scheme.

    PubMed

    Faber, Jack H; Creamer, Rachel E; Mulder, Christian; Römbke, Jörg; Rutgers, Michiel; Sousa, J Paulo; Stone, Dorothy; Griffiths, Bryan S

    2013-04-01

    A large number of biological indicators have been proposed over the years for assessing soil quality. Although many of those have been applied in monitoring schemes across Europe, no consensus exists on the extent to which these indicators might perform best and how monitoring schemes can be further optimized in terms of scientific and policy relevance. Over the past decade, developments in environmental monitoring and risk assessment converged toward the use of indicators and endpoints that are related to soil functioning and ecosystem services. In view of the proposed European Union (EU) Soil Framework Directive, there is an urgent need to identify and evaluate indicators for soil biodiversity and ecosystem services. The recently started integrated project, Ecological Function and Biodiversity Indicators in European Soils (EcoFINDERS), aims to address this specific issue within the EU Framework Program FP7. Here, we 1) discuss how to use the concept of ecosystem services in soil monitoring, 2) review former and ongoing monitoring schemes, and 3) present an analysis of metadata on biological indicators in some EU member states. Finally, we discuss our experiences in establishing a logical sieve approach to devise a monitoring scheme for a standardized and harmonized application at European scale. PMID:23325463

  15. Lessons from Nature: Unraveling Biological C—H Bond Activation

    PubMed Central

    Stone, Kari L.; Borovik, A. S.

    2009-01-01

    The cleavage of unactivated C—H bonds is one of the most challenging reactions in chemical biology. Metalloenzymes have evolved that efficiently perform these transformations with exquisite control of selectivity; however, a proposed requirement is the generation of highly reactive intermediates that could be lethal. A thermodynamic argument involving the putative reactive species is outlined, whereby the interplay between two tunable parameters, redox potential and pKa, may be the key to sustainable function. In addition, factors that control these parameters are also described, including hydrogen-bonding networks found within protein active sites. Synthetic examples are used to corroborate these ideas. PMID:19297238

  16. Nanodiamonds as Carriers for Address Delivery of Biologically Active Substances

    NASA Astrophysics Data System (ADS)

    Purtov, K. V.; Petunin, A. I.; Burov, A. E.; Puzyr, A. P.; Bondar, V. S.

    2010-03-01

    Surface of detonation nanodiamonds was functionalized for the covalent attachment of immunoglobulin, and simultaneously bovine serum albumin and Rabbit Anti-Mouse Antibody. The nanodiamond-IgGI125 and RAM-nanodiamond-BSAI125 complexes are stable in blood serum and the immobilized proteins retain their biological activity. It was shown that the RAM-nanodiamond-BSAI125 complex is able to bind to the target antigen immobilized on the Sepharose 6B matrix through antibody-antigen interaction. The idea can be extended to use nanodiamonds as carriers for delivery of bioactive substances (i.e., drugs) to various targets in vivo.

  17. [Studies on the constituents and biological activities of simaroubaceous plants].

    PubMed

    Ohmoto, T

    1995-04-01

    In search of new compounds in simaroubaceous plants, we have been investigating naturally occurring substances [alkaloids, quassinoids, limonoids and picrotoxane-type terpenoids] on the following subjects: I. chemical studies on the constituents of Japanese simaroubaceous plants (I-1 and 2), II. chemical studies on the constituents of Indonesian and Chinese simaroubaceous plants (II-1-9), III. biological activities of the isolated natural compounds mainly and the chemical modification analogs (III-1-9). This article reviews the results obtained in our laboratory since 1976 on the subjects of I, II and III. PMID:7602495

  18. Effect of glyphosate on the microbial activity of two Brazilian soils

    Microsoft Academic Search

    A. S. F. Araújo; R. T. R. Monteiro; R. B. Abarkeli

    2003-01-01

    Glyphosate [N-(phosphonomethyl)-glycine] is a broad-spectrum, non-selective, post-emergence herbicide that is widely used in agricultural. We studied, in vitro, changes in the microbial activity of typical Hapludult and Hapludox Brazilian soils, with and without applied glyphosate. Glyphosate was applied at a rate of 2.16 mg glyphosate kg?1 of soil and microbial activity was measured by soil respiration (evolution of CO2) and

  19. Land-use influences the distribution and activity of high affinity CO-oxidizing bacteria associated to type I-coxL genotype in soil

    PubMed Central

    Quiza, Liliana; Lalonde, Isabelle; Guertin, Claude; Constant, Philippe

    2014-01-01

    Soil carboxydovore bacteria are the biological sink of atmospheric carbon monoxide (CO). The initial oxidation of CO is catalyzed by a CO-dehydrogenase (CODH), and the gene coxL encodes the large subunit of the enzyme. Only a few carboxydovore isolates were shown to oxidize atmospheric CO and little is known about the potential impact of global change on the ecophysiology of this functional group. The main objective of this study was to assess the impact of land-use and soil properties on coxL gene diversity and identify molecular indicators for the soil uptake of atmospheric CO. Soil samples were collected in three neighboring sites encompassing different land-use types, namely deciduous forest, larch plantation and maize field. CO uptake activity was related to total carbon and nitrogen content in soil, with the highest activity observed in deciduous forest. An extensive coxL database was assembled to optimize a PCR detection assay targeting sequences belonging to functional type I-CODH and hypothetical type II-CODH. Fully replicated coxL gene libraries unveiled a unique molecular signature in deciduous forest soil, with enrichment of type I sequences. Genetic profiles of larch and maize monocultures were not statistically different and showed higher level of coxL gene richness than deciduous forest. Soil water content and CO uptake activity explained 38% of the variation of coxL gene profiles in a canonical ordination analysis, leading to the identification of sequences belonging to the ?-Proteobacteria cluster as indicator for high affinity CO uptake activity. Enrichment of type I and ?-Proteobacteria coxL sequences in deciduous forest were confirmed by qPCR in an independent soil survey. CO uptake activity in model carboxydovore bacteria suggested that a significant fraction of detected putative high affinity CO oxidizers were active in soil. Land-use was a driving force separating coxL diversity in deciduous forest from monocultures. PMID:24971077

  20. Land-use influences the distribution and activity of high affinity CO-oxidizing bacteria associated to type I-coxL genotype in soil.

    PubMed

    Quiza, Liliana; Lalonde, Isabelle; Guertin, Claude; Constant, Philippe

    2014-01-01

    Soil carboxydovore bacteria are the biological sink of atmospheric carbon monoxide (CO). The initial oxidation of CO is catalyzed by a CO-dehydrogenase (CODH), and the gene coxL encodes the large subunit of the enzyme. Only a few carboxydovore isolates were shown to oxidize atmospheric CO and little is known about the potential impact of global change on the ecophysiology of this functional group. The main objective of this study was to assess the impact of land-use and soil properties on coxL gene diversity and identify molecular indicators for the soil uptake of atmospheric CO. Soil samples were collected in three neighboring sites encompassing different land-use types, namely deciduous forest, larch plantation and maize field. CO uptake activity was related to total carbon and nitrogen content in soil, with the highest activity observed in deciduous forest. An extensive coxL database was assembled to optimize a PCR detection assay targeting sequences belonging to functional type I-CODH and hypothetical type II-CODH. Fully replicated coxL gene libraries unveiled a unique molecular signature in deciduous forest soil, with enrichment of type I sequences. Genetic profiles of larch and maize monocultures were not statistically different and showed higher level of coxL gene richness than deciduous forest. Soil water content and CO uptake activity explained 38% of the variation of coxL gene profiles in a canonical ordination analysis, leading to the identification of sequences belonging to the ?-Proteobacteria cluster as indicator for high affinity CO uptake activity. Enrichment of type I and ?-Proteobacteria coxL sequences in deciduous forest were confirmed by qPCR in an independent soil survey. CO uptake activity in model carboxydovore bacteria suggested that a significant fraction of detected putative high affinity CO oxidizers were active in soil. Land-use was a driving force separating coxL diversity in deciduous forest from monocultures. PMID:24971077

  1. Impact of warming and drying on microbial activity in subarctic tundra soils: inferences from patterns in extracellular enzyme activity

    NASA Astrophysics Data System (ADS)

    Schade, J. D.; Natali, S.; Spawn, S.; Sistla, S.; Schuur, E. A. G.

    2014-12-01

    Permafrost contains a large pool of carbon that has accumulated for thousands of years, and remains frozen in organic form. As climate warms, permafrost thaw will increase rates of microbial breakdown of old soil organic matter (SOM), accelerating release of carbon to the atmosphere. Higher rates of microbial decomposition may also release reactive nitrogen, which may increase plant production and carbon fixation. The net effect on atmospheric carbon, and the strength of climate feedback, depends on the balance between direct and indirect effects of increased microbial activity, which depends on changes in soil conditions and microbial responses to them. In particular, soil moisture and availability of C and N for microbes strongly influence soil respiration and primary production. Current understanding of changes in these factors as climate warms is limited. We present results from analysis of soil extracellular enzyme activities (EEA) from a long-term warming and drying experiment in subarctic Alaskan tundra (the CiPEHR experiment) as an indicator of changes in soil microbial activity and relative availability of C and N for microbes. We collected soil samples from control (C), warming (W), and warming + drying (WD) treatments and used fluorometric methods to estimate EEA in shallow (0-5 cm) and deep (5-15) soils. We measured soil moisture, SOM, and C:N, and plant tissue C:N as an indicator of N availability. Activity of N-acquiring enzymes was higher in WD soils at both depths. Carbon EEA in W soils was lower in surface, but higher in deeper soils. We also found significantly lower soil C:N in both W and WD in deeper soils, where C:N was generally lower than surface. In general, EEA results suggest drying leads to increased C availability relative to N. This may be due to lower soil moisture leading to greater aeration of soils in WD plots relative to W plots, which may be saturated due to significant land subsidence. Greater aeration may increase efficiency of carbon use by microbes, effectively increasing carbon availability for microbes in WD soils relative to W soils. This suggests that drying may reduce N recycling by microbes, potentially reducing plant production and increasing soil respiration relative to carbon fixation, increasing the likelihood that permafrost thaw will be a positive feedback on climate change.

  2. Effect of biochar amendment on soil carbon balance and soil microbial activity

    Microsoft Academic Search

    S. Steinbeiss; G. Gleixner; M. Antonietti

    2009-01-01

    We investigated the behavior of biochars in arable and forest soil in a greenhouse experiment in order to prove that these amendments can increase carbon storage in soils. Two qualities of biochar were produced by hydrothermal pyrolysis from 13C labeled glucose (0% N) and yeast (5% N), respectively. We quantified respiratory losses of soil and biochar carbon and calculated mean

  3. Influence of heavy metals on soil microbial activities

    Microsoft Academic Search

    Hiroyuki Hattori

    1992-01-01

    Studies were carried out to evaluate the influence of Cd, Cr, Cu, Ni, Pb, or Zn on the decomposition of organic matter in soils and on their microflora. The heavy metals were added to samples of Gley soil and Light-colored Andosol at the level of 10 ?mol\\/g soil, respectively. Three days after the addition, sewage sludge was mixed with the

  4. Sensitivity to soil moisture by active and passive microwave sensors

    Microsoft Academic Search

    Yang Du; Fawwaz T. Ulaby; M. Craig Dobson

    1999-01-01

    The backscatter measured by a radar and the emission measured by a radiometer are both very sensitive to the moisture content m, of bare-soil surfaces. Vegetation cover complicates the scattering and emission processes, presumably masking the soil surface and reducing soil-moisture sensitivity. Although researchers generally agree with the preceding statement, numerous claims and counterclaims have been voiced, espousing the superiority

  5. Soil enzyme activities in two forage systems following application of different rates of swine lagoon effluent or ammonium nitrate

    Microsoft Academic Search

    Kannan Iyyemperumal; Wei Shi

    2008-01-01

    Land application of swine lagoon effluent (SLE) to forage production systems is widespread in the southeastern USA and often leads to change in soil properties. Although soil enzymes are crucial to the degradation of soil organic matter and cycling of nutrients, the impacts of SLE application on soil enzyme activities have not been well characterized. We assessed the activities of

  6. Organic matter inputs shift soil enzyme activity and allocation patterns in a wet tropical forest

    E-print Network

    Cleveland, Cory

    Organic matter inputs shift soil enzyme activity and allocation patterns in a wet tropical forest enzymes mediate organic matter turnover and nutrient cycling yet remain little studied in one of Earth properties and enzyme activities in a lowland tropical forest. We assayed six hydrolytic soil enzymes

  7. The Soil Moisture Active Passive Experiments (SMAPEx) for SMAP Algorithm Development (Invited)

    Microsoft Academic Search

    R. Panciera; J. P. Walker; D. Ryu; D. Gray; T. J. Jackson; H. Yardley

    2010-01-01

    The availability of global L-band observations from passive (the recently launched SMOS), and active (such as the PALSAR) microwave sensors has boosted the interest in making joint use of the two techniques to improve the retrieval of global near-surface soil moisture at unprecedented resolutions. The Soil Moisture Active Passive (SMAP) mission (scheduled launch, 2014) will fully exploit this synergy by

  8. Phosphatase activity in the rhizosphere and its relation to the depletion of soil organic phosphorus

    Microsoft Academic Search

    J. C. Tarafdar; A. Jungk

    1987-01-01

    The distribution of phosphatase activity and of phosphate fractions of the soil in the proximity of roots was studied in order to evaluate the significance of phosphatases in P nutrition of various plants (Brassica oleracea, Allium cepa, Triticum aestivum, Trifolium alexandrinum). A considerable increase in both acid and alkaline phosphatase activity in all the four soil-root interfaces was observed. Maximum

  9. Enhancing Potato System Sustainability: Crop Rotation Impacts on Soil Phosphatase Activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato is a species with a low efficiency of acquiring soil P. Rotation crops may potentially influence P uptake by potato by increasing soil organic acids, phosphatase activity, and microbial biomass. However, this kind of information is very limited. We measured the activities of acid phosphatase,...

  10. Shifts of soil enzyme activities in wetlands exposed to elevated CO 2

    Microsoft Academic Search

    Hojeong Kang; Seon-Young Kim; Nathalie Fenner; Chris Freeman

    2005-01-01

    Wetlands play a key role in global biogeochemical cycles, and as such, the effects of global climatic changes on these systems are of great importance. In this study, we assessed impacts of elevated CO2 on soil enzyme activities in different types of wetlands. We hypothesised that elevated CO2, by increasing DOC supply into the soil, would modify enzyme activities. Intact

  11. Syntheses and biological activities of renin inhibitors containing statine analogues.

    PubMed

    Nishi, T; Saito, F; Nagahori, H; Kataoka, M; Morisawa, Y; Yabe, Y; Sakurai, M; Higashida, S; Shoji, M; Matsushita, Y

    1990-01-01

    Syntheses and biological activities of dipeptide renin inhibitors that contain statine analogues are described. The key steps of the synthetic approach to dipeptide renin inhibitors are the asymmetric synthesis of 2(R)-substituted-3-aminocarbonylpropionic acids and the diastereoselective syntheses of (3S,4S)-statine analogues. These inhibitors (2,14-40) inhibited human renin in the 3-140 nM range. Inhibitor ES 6864 (2) was found to be a highly potent inhibitor of human renin (IC50: 4.6 x 10(-9) M) and showed high enzyme specificity. Oral administration of ES 6864 at 3 mg/kg to conscious, sodium-depleted marmosets inhibited plasma renin activity (PRA) more than 80% after 1 h. PMID:2110866

  12. Biological activity of lactoferrin-functionalized biomimetic hydroxyapatite nanocrystals

    PubMed Central

    Nocerino, Nunzia; Fulgione, Andrea; Iannaccone, Marco; Tomasetta, Laura; Ianniello, Flora; Martora, Francesca; Lelli, Marco; Roveri, Norberto; Capuano, Federico; Capparelli, Rosanna

    2014-01-01

    The emergence of bacterial strains resistant to antibiotics is a general public health problem. Progress in developing new molecules with antimicrobial properties has been made. In this study, we evaluated the biological activity of a hybrid nanocomposite composed of synthetic biomimetic hydroxyapatite surface-functionalized by lactoferrin (LF-HA). We evaluated the antimicrobial, anti-inflammatory, and antioxidant properties of LF-HA and found that the composite was active against both Gram-positive and Gram-negative bacteria, and that it modulated proinflammatory and anti-inflammatory responses and enhanced antioxidant properties as compared with LF alone. These results indicate the possibility of using LF-HA as an antimicrobial system and biomimetic hydroxyapatite as a candidate for innovative biomedical applications. PMID:24623976

  13. Creating Common Ground: Activities of the Soil Health Dialog Workgroup

    NASA Astrophysics Data System (ADS)

    Lindbo, David L.; Moebius-Clune, Bianca; Hatfield, Jerry; Buckner, William; Conklin, Neil; McMahon, Sean; Haney, Richard; Muller, Paul; Martin, Larkin; Shaw, Richard; Eyrich, Ted; Martens, Klaas; Archuleta, Ray; Thompson, Mary

    2014-05-01

    The concept of Soil Health has come to forefront as a soil management concept for soil scientists, agronomists, producers, land-use planners, and environmental advocates. Although many see this simply as a way to increase organic matter in the soil it is much more than that and has implications to a broader management decisions. A diverse group of stake holders ranging from scientists to consultants, conventional to organic farmers, governmental to NGOs met to start a dialog about soil health with an overarching goal to adopt practices that will improve soil health across a wide area and for a wide variety of land uses. The group recognized the critical need for using soil health as a cornerstone of sustainable soil management. The group also realized that a consistent and coherent message about soil health needed to be developed that would be inclusive to all stake holders. Furthermore the group recognized that if soil health is to be promoted we all need to know and agree on how to measure it and interpret the results. The first outcome from the meeting was the creation of several teams comprised of individuals with the diverse interests as list above. The first was tasked to review and develop a definition of soil health. The first group, after much debate, decided on the adoption of the USDA-NRCS definition of Soil Health as the most effective way to begin. This definition was presented as a press release from the Farm Foundation in early December 2013 in conjunction with World Soil Day. The second group was tasked to review, develop or recommend standard measurement techniques to assess soil health. The methods group is in the process of reviewing methods and hopes to have a preliminary list out for broader review by mid-year. This presentation reviews current progress and asks for input from the Soil Science community at large.

  14. Soil microbial activities in Mediterranean environment as desertification indicators along a pluviometric gradient.

    NASA Astrophysics Data System (ADS)

    Novosadova, I.; Zahora, J.; Ruiz Sinoga, J. D.

    2009-04-01

    In the Mediterranean areas of Southern Spain, unsuitable agricultural practices with adverse environmental conditions (López Bermúdez and Albaladejo, 1990), have led to a permanent degradation and loss of soil fertility. This includes deterioration of the natural plant cover, which protects against erosion by contributing organic matter, the main prerequisite of ecosystem sustainability (Grace et al., 1994). Physico-chemical, microbiological and biochemical soil properties are very responsive and provide immediate and precise information on small changes occurring in soil (Dick and Tabatabai, 1993). There is increasing evidence that such parameters are also sensitive indicators of ecology stress suffered by a soil and its recovery, since microbial activity has a direct influence on the stability and fertility of ecosystems (Smith and Papendick, 1993). One method for recovering degraded soils of such semiarid regions, with their low organic matter content, is to enhance primary productivity and carbon sequestration without any additional nitrogen fertilization and preferably without incorporation of leguminous plants (Martinez Mena et al., 2008). Carbon rich materials can sustain microbial activity and growth, thus enhancing biogeochemical nutrient cycles (Pascual et al., 1997). The present study is focused in the role of physico-chemical and microbial soil properties in Mediterranean environment, in terms of in situ and ex situ microbial transformation of soil carbon and nitrogen, in order to characterise the key soil microbial activities which could strongly affect carbon and nitrogen turnover in soil and hereby soil fertility and soil organic matter "quality". These microbial activities could at unsuitable agricultural practices with adverse environmental conditions induce unfavourable hydrologycal tempo-spatial response. The final results shown modifications in the soil properties studied with the increasing of the aridity. Such changes suppose the soil degradation what make us the existence of soil degradational processes. Physico-chemical properties and soil microbiological activities analysed shown a higher relationship tend to the soil degradation along a pluviometric gradient selected. Biothic and abiothic factors are going to be more degraded conditions according with a reduction of pluviometric conditions. The soil degradation observed across the analysis of the more stable soil properties, that we can denominate from the slow cycle, bring as a consequence an important reduction of the vegetation cover, and therefore in the soil protection, decreasing their soil moisture content and their soil permeability and the cationic exchange capacity, as good key factor to determine the soil health. When these processes take place, an increase of runoff, high pedregosity and crusting may occur in the soil surface. Concerning the regional scale spatial variability, results of experimental field work conducted along a climatic transect, from the Mediterranean climate to the arid zone in the south of Spain, show that: (1) organic matter content, and aggregate size and stability decrease with aridity; (2) the rate of change of these variables along the climatic transect is non-linear and (3) the analysis of the soil properties shown a higher and inverse correlation between soil degradation levels and organic carbon sequestration capacity; (4) the soil respiration were tightly coupled with the carbon compounds available in soil (5) the in situ ammonification was nearly the same along a pluviometric gradient; (6) the nitrification was increasing with aridity identically in control soils, and after the addition of cellulose and raw silk; (7) the contact time of the water with the soil matrix was sufficient to retain NH4+, but insufficient for a retention of NO3-. (8) the key factor influencing the movement of nitrate and thereby promoting the losses of base cations was the frequency and intensity of precipitation not only a soil-internal N surplus. A steplike threshold exists at the semiarid area, which sharply sepa

  15. BIOLOGICALLY ACTIVE NATURAL PRODUCTS OF THE GENUS CALLICARPA?

    PubMed Central

    JONES, WILLIAM P.; KINGHORN, A. DOUGLAS

    2009-01-01

    About 20 species from Callicarpa have reported ethnobotanical and ethnomedical uses, and several members of this genus are well known in the traditional medical systems of China and South Asia. Ethnomedical reports indicate their use in the treatment of hepatitis, rheumatism, fever, headache, indigestion, and other ailments. Several species of Callicarpa have been reported to be used against cancer (e.g., Callicarpa americana root to treat skin cancer and Callicarpa rubella bark to treat tumors of the large intestine). Extracts from about 14 species in this genus have been evaluated for biological activity, including antibacterial, antifungal, anti-insect growth, cytotoxic, and phytotoxic activities. In addition to amino acids, benzenoids, simple carbohydrates, and lipids, numerous diterpenes, flavonoids, phenylpropanoids, phytosterols, sesquiterpenes, and triterpenes have been detected in or isolated from the genus Callicarpa. The essential oils of Callicarpa americana have recently been reported to have antialgal and phytotoxic activities, and several isolates from this species (and C. japonica) were identified as contributing to the mosquito bite-deterrent activity that was first indicated by folkloric usage. Recent bioassay-guided investigations of C. americana extracts have resulted in the isolation of several active compounds, mainly of the clerodane diterpene structural type. PMID:19830264

  16. A biologically active surface enzyme assembly that attenuates thrombus formation.

    PubMed

    Qu, Zheng; Muthukrishnan, Sharmila; Urlam, Murali K; Haller, Carolyn A; Jordan, Sumanas W; Kumar, Vivek A; Marzec, Ulla M; Elkasabi, Yaseen; Lahann, Joerg; Hanson, Stephen R; Chaikof, Elliot L

    2011-12-20

    Activation of hemostatic pathways by blood-contacting materials remains a major hurdle in the development of clinically durable artificial organs and implantable devices. We postulate that surface-induced thrombosis may be attenuated by the reconstitution onto blood contacting surfaces of bioactive enzymes that regulate the production of thrombin, a central mediator of both clotting and platelet activation cascades. Thrombomodulin (TM), a transmembrane protein expressed by endothelial cells, is an established negative regulator of thrombin generation in the circulatory system. Traditional techniques to covalently immobilize enzymes on solid supports may modify residues contained within or near the catalytic site, thus reducing the bioactivity of surface enzyme assemblies. In this report, we present a molecular engineering and bioorthogonal chemistry approach to site-specifically immobilize a biologically active recombinant human TM fragment onto the luminal surface of small diameter prosthetic vascular grafts. Bioactivity and biostability of TM modified grafts is confirmed in vitro and the capacity of modified grafts to reduce platelet activation is demonstrated using a non-human primate model. These studies indicate that molecularly engineered interfaces that display TM actively limit surface-induced thrombus formation. PMID:23532366

  17. A biologically active surface enzyme assembly that attenuates thrombus formation

    PubMed Central

    Qu, Zheng; Muthukrishnan, Sharmila; Urlam, Murali K.; Haller, Carolyn A.; Jordan, Sumanas W.; Kumar, Vivek A.; Marzec, Ulla M.; Elkasabi, Yaseen; Lahann, Joerg; Hanson, Stephen R.

    2013-01-01

    Activation of hemostatic pathways by blood-contacting materials remains a major hurdle in the development of clinically durable artificial organs and implantable devices. We postulate that surface-induced thrombosis may be attenuated by the reconstitution onto blood contacting surfaces of bioactive enzymes that regulate the production of thrombin, a central mediator of both clotting and platelet activation cascades. Thrombomodulin (TM), a transmembrane protein expressed by endothelial cells, is an established negative regulator of thrombin generation in the circulatory system. Traditional techniques to covalently immobilize enzymes on solid supports may modify residues contained within or near the catalytic site, thus reducing the bioactivity of surface enzyme assemblies. In this report, we present a molecular engineering and bioorthogonal chemistry approach to site-specifically immobilize a biologically active recombinant human TM fragment onto the luminal surface of small diameter prosthetic vascular grafts. Bioactivity and biostability of TM modified grafts is confirmed in vitro and the capacity of modified grafts to reduce platelet activation is demonstrated using a non-human primate model. These studies indicate that molecularly engineered interfaces that display TM actively limit surface-induced thrombus formation. PMID:23532366

  18. The Pediocin AcH Precursor Is Biologically Active

    PubMed Central

    Ray, Bibek; Schamber, Robin; Miller, Kurt W.

    1999-01-01

    The properties of the pediocin AcH precursor, prepediocin AcH, have been studied to gain insight into how producer cells may protect themselves from the activity of intracellular prebacteriocins. The native 62-amino-acid precursor and the 44-amino-acid mature species were expressed in Escherichia coli host strains that lack the leader peptide processing enzyme, PapD. Both forms inhibited the growth of the test bacterium Listeria innocua Lin11, indicating that the native precursor is biologically active. The two species also were synthesized in the context of maltose-binding protein chimeric proteins to facilitate the measurement of their relative specific activities. The chimeric form of the precursor was ?80% as active as the chimeric mature species. Of relevance to cell protection and pediocin AcH production, it was determined that the precursor is strongly susceptible to inactivation by reducing agents and to degradation by chymotrypsin and endogenous E. coli proteases. Taken together, the results indicate that the activity of prepediocin AcH may have to be controlled prior to secretion to prevent toxicity to the host. Perhaps producer cells avoid membrane damage by maintaining the precursor in a reduced inactive state or by degrading molecules whose secretion is delayed. PMID:10347002

  19. Protease resistant variants of FGF1 with prolonged biological activity.

    PubMed

    Kobielak, Agnieszka; Zakrzewska, Ma?gorzata; Kostas, Micha?; Jakimowicz, Piotr; Otlewski, Jacek; Krowarsch, Daniel

    2014-05-01

    Therapeutic potential of human acidic fibroblast growth factor (FGF1) resulting from its undeniable role in angiogenesis and wound healing processes is questioned due to its low stability and short half-life in vivo. Our previous studies showed that prolonged biological activity of FGF1 can be achieved by increasing its proteolytic resistance directly linked to improved global thermostability. In this study, we applied an alternative method of generation of long-lasting FGF1 variants by rigidification of the growth factor's segment highly sensitive to proteases action. In order to determine regions the most prone to enzymatic degradation, we used limited proteolysis by trypsin combined with mass spectrometry analysis. We found that the initial proteolytic cleavages occurred mainly within the C-terminal region of the wild-type protein, pointing on its significant role in growth factor degradation. Based on bioinformatic analysis, we introduced two single mutations (C117P, K118V) within ?-strand XI and combined them in a double mutant. We determined resistance to proteolysis, biophysical properties and biological activities of obtained variants. All of them occurred to be significantly less susceptible to trypsin (up to 100-fold) and also to chymotrypsin degradation comparing to the wild-type protein. Interestingly, all variants were not more thermostable than the wild-type FGF1. We attributed this dramatic increase in resistance to proteolysis to entropic stabilization of C-terminal region. PMID:24304385

  20. A biologically active peptide mimetic of N-acetylgalactosamine/galactose

    PubMed Central

    Eggink, Laura L; Hoober, J Kenneth

    2009-01-01

    Background Glycosylated proteins and lipids are important regulatory factors whose functions can be altered by addition or removal of sugars to the glycan structure. The glycans are recognized by sugar-binding lectins that serve as receptors on the surface of many cells and facilitate initiation of an intracellular signal that changes the properties of the cells. We identified a peptide that mimics the ligand of an N-acetylgalactosamine (GalNAc)-specific lectin and asked whether the peptide would express specific biological activity. Findings A 12-mer phage display library was screened with a GalNAc-specific lectin to identify an amino acid sequence that binds to the lectin. Phage particles that were eluted from the lectin with free GalNAc were considered to have been bound to a GalNAc-binding site. Peptides were synthesized with the selected sequence as a quadravalent structure to facilitate receptor crosslinking. Treatment of human peripheral blood mononuclear cells for 24 h with the peptide stimulated secretion of interleukin-8 (IL-8) but not of IL-1?, IL-6, IL-10, or tumor necrosis factor-? (TNF-?). The secretion of IL-21 was stimulated as strongly with the peptide as with interferon-?. Conclusion The data indicate that the quadravalent peptide has biological activity with a degree of specificity. These effects occurred at concentrations in the nanomolar range, in contrast to free sugars that generally bind to proteins in the micro- to millimolar range. PMID:19284521