Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • AGRIS (United Nations, Food and Agriculture Organization)  (9)
Type of Medium
Language
Year
  • 1
    Language: English
    In: Journal of Soil and Water Conservation, Nov-Dec, 2007, Vol.62(6), p.139A(5)
    Description: Role of soil in causing global warming is discussed. Soils are major players in the carbon cycle. Soils contain the equivalent of about 300 times the amount of carbon now released annually through the burning of fossil fuels. In many soils, carbon stocks contain large amounts of nitrogen, whose metabolism by microorganisms can also contribute to greenhouse gas emissions. It is shown that small changes of the amount of carbon contained in soils may lead to sources or sinks of greenhouse gases. Increased release of carbon by world soils can drastically exacerbate atmospheric carbon dioxide (CO sub(2)) levels, leading to accelerated global warming and to a positive feedback mechanism that may cause climate change to get completely out of hand.
    Keywords: Air Pollution -- Social Aspects ; Air Pollution -- Control ; Global Warming -- Influence ; Soil Ecology -- Research ; Soil Chemistry -- Research
    ISSN: 0022-4561
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Ecological Modelling, 2011, Vol.222(12), pp.1998-2010
    Description: ► The individual-based INDISIM-SOM model is far more sensitive to some parameters than to others. ► Key parameters for the evolution of C and N are microbial maintenance, energy, and death probability. ► The nitrification rate, in particular, appears highly affected by the death probability. ► The sensitivity analysis indicates what simplification of the model is possible. ► It also shows which parameters need to be evaluated with more accuracy than is currently achievable. The fate of soil carbon and nitrogen compounds in soils in response to climate change is currently the object of significant research. In particular, there is much interest in the development of a new generation of micro-scale models of soil ecosystems processes. Crucial to the elaboration of such models is the ability to describe the growth and metabolism of small numbers of individual microorganisms, distributed in a highly heterogeneous environment. In this context, the key objective of the research described in this article was to further develop an individual-based soil organic matter model, INDISIM-SOM, first proposed a few years ago, and to assess its performance with a broader experimental data set than previously considered. INDISIM-SOM models the dynamics and evolution of carbon and nitrogen associated with organic matter in soils. The model involves a number of state variables and parameters related to soil organic matter and microbial activity, including growth and decay of microbial biomass, temporal evolutions of easily hydrolysable N, mineral N in ammonium and nitrate, CO and O . The present article concentrates on the biotic components of the model. Simulation results demonstrate that the model can be calibrated to provide good fit to experimental data from laboratory incubation experiments performed on three different types of Mediterranean soils. In addition, analysis of the sensitivity toward its biotic parameters shows that the model is far more sensitive to some parameters, i.e., the microbial maintenance energy and the probability of random microbial death, than to others. These results suggest that, in the future, research should focus on securing better measurements of these parameters, on environmental determinants of the switch from active to dormant states, and on the causes of random cell death in soil ecosystems.
    Keywords: Individual-Based Model ; Soil Microbial Activity ; Soil Organic Matter ; C and N Mineralization ; Microbial Parameters ; Environmental Sciences ; Ecology
    ISSN: 0304-3800
    E-ISSN: 1872-7026
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Soil Science Society of America journal, 2011, Vol.75(6), pp.2037-2048
    Description: When the Soil Science Society of America was created, 75 yr ago, the USA was suffering from major dust storms, causing the loss of enormous amounts of topsoil as well as human lives. These catastrophic events reminded public officials that soils are essential to society's well-being. The Soil Conservation Service was founded and farmers were encouraged to implement erosion mitigation practices. Still, many questions about soil processes remained poorly understood and controversial. In this article, we argue that the current status of soils worldwide parallels that in the USA at the beginning of the 20th century. Dust bowls and large-scale soil degradation occur over vast regions in a number of countries. Perhaps more so even than in the past, soils currently have the potential to affect populations critically in several other ways as well, from their effect on global climate change, to the toxicity of brownfield soils in urban settings. Even though our collective understanding of soil processes has experienced significant advances since 1936, many basic questions still remain unanswered, for example whether or not a switch to no-till agriculture promotes C sequestration in soils, or how to account for microscale heterogeneity in the modeling of soil organic matter transformation. Given the enormity of the challenges raised by our (ab)uses of soils, one may consider that if we do not address them rapidly, and in the process heed the example of U.S. public officials in the 1930s who took swift action, humanity may not get a chance to explore other frontiers of science in the future. From this perspective, insistence on the fact that soils are critical to life on earth, and indeed to the survival of humans, may again stimulate interest in soils among the public, generate support for soil research, and attract new generations of students to study soils. ; p. 2037-2048.
    Keywords: Dust Storms ; Students ; Carbon Sequestration ; Topsoil ; Urban Soils ; Society ; No-Tillage ; Soil Organic Matter ; Humans ; Climate Change ; Models ; Farmers ; Soil Degradation ; Toxicity ; Soil Conservation
    ISSN: 0361-5995
    E-ISSN: 14350661
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Water, Air, & Soil Pollution, 2010, Vol.209(1), pp.377-390
    Description: Near-infrared diffuse reflectance sensing (NIRS) of soils has been the object of considerable interest and research in the last few years. This has been motivated by the prospect that this method seems to provide a cheap, convenient alternative to conventional, time-consuming methods for the measurement of a wide range of soil parameters. In particular, various authors have advocated that NIRS could be used to measure rapidly and non-destructively the concentration of trace metals in surface soils. Correlation analyses between NIRS spectra and trace metal concentration have yielded inconclusive results to date, suggesting that trace metal concentration may belong to a class of “tertiary” soil parameters, linked to NIRS spectra through “surrogate”, or indirect, correlations, involving some other primary or secondary parameter like clay or organic matter content, to which NIRS spectra are very sensitive. To assess the validity of this surrogate correlation hypothesis in the case of trace metals, experiments were carried out with soil samples varying only in the amount of trace metals they contain. Field-aged Hudson and Arkport soil pots spiked with Cu and Zn, freshly spiked samples of the same soils, and samples of a metalliferous peat soil from Western New York naturally rich in Cd and Zn were subjected to NIRS under laboratory conditions. Detailed analysis indicates that the NIR spectrum is sensitive to sample handling, including the orientation of the samples in the NIRS instrument, but that, at the same time, there is no discernable effect of the presence of trace metals on any part of the NIR spectrum. These results provide strong experimental support to the hypothesis of “surrogate” correlation for trace metals, and indicate that trace metals, even in severely contaminated soils, should not interfere with the NIR sensing of primary or secondary parameters, like organic matter content. Further work is needed to determine if this feature of NIR spectra extends to other soil chemical parameters.
    Keywords: Soil metal contamination ; Chemical analysis ; Near-infrared spectroscopy ; Remote sensing
    ISSN: 0049-6979
    E-ISSN: 1573-2932
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: 2015
    Keywords: Soil Water ; Near-Infrared Spectroscopy ; Soil Pollution ; Plant Growth ; Heavy Metals
    Source: AGRIS (Food and Agriculture Organization of the United Nations)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    In: Soil Science, 2010, Vol.175(8), pp.363-374
    Description: The need to predict with reasonable accuracy the fate of soil C and N compounds in soils in response to climate change is stimulating interest in a new generation of microscale models of soil ecosystem processes. Essential to the development of such models is the ability to describe the growth and metabolism of small numbers of individual microorganisms. In this context, the key objective of the research described in this article was to further develop an individual-based soil organic matter (SOM) model, INDISIM-SOM, first proposed a few years ago, and to assess its performance with a broader data set than previously considered. The INDISIM-SOM models the dynamics and evolution of C and N associated with organic matter in soils. The model involves a number of state variables and parameters related to SOM and microbial activity, including growth and decay of microbial biomass, temporal evolution of mineralized intermediate C and N, mineral N in ammonium and nitrate, carbon dioxide, and O2. Simulation results demonstrate good fit of the model to experimental data from laboratory incubation experiments performed on three different types of Mediterranean soils. A second objective was to determine the sensitivity of the model toward its various parameters. Sensitivity was small for several of the parameters, suggesting possible simplifications of the model for specific uses, but was significant particularly for the parameter associated with the fraction of the soil C present in the biomass. These results suggest that research should be focused on improving the measurement of this latter parameter.
    Keywords: Microorganisms ; Metabolism ; Climate Change ; Soil Microorganisms ; Soil Testing ; Evolution ; Simulation ; Biomass ; Carbon ; Nitrogen;
    ISSN: 0038-075X
    E-ISSN: 15389243
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: Revista Brasileira de Ciência do Solo, 2010
    Description: The present essay is meant to provide some background on the evolution of the soil science community in Brazil, since its inception, to describe its current situation, and to outline a number of opportunities and challenges facing the discipline in decades to come. The origin of Brazilian agronomy dates back to the beginning of the 19th century as a subdiscipline of botany, and its association with chemistry would later establish it as a science. In the middle of the 19th century, agricultural chemistry was born as a result of this association, leading to the establishment of edaphology, a branch of Soil Science. Another branch of Soil Science, known as pedology, was established as an applied and scientific knowledge in Brazil during the middle of the 20th century. During the same period, the Brazilian Soil Science Society (SBCS) was created, merging the knowledge of both branches and gathering all scientists involved. Twenty years after the SBCS foundation, the creation of Graduate Programs made Brazilian Soil Science enter the modern era, generating crucial knowledge to reach the current levels of agricultural productivity. Part of a community composed of 25 Soil Departments, 15 Graduate Programs and a great number of institutions that promote research and technology transfer, Brazilian soil scientists are responsible for developing solutions for sustainable development, by generating, adapting and transferring technology to the benefit of the country. The knowledge produced by SBCS members has been particularly significant for Brazil to achieve the status of most competitive tropical agriculture in the world. In the future decades, Soil Science will still remain topical in discussions regarding environment care and production of food and fibers, in addition, it will be essential and strategic for certain issues, such as water quality, reducing poverty and development of renewable sources of energy.
    Description: A presente revisão tem por objetivo apresentar a evolução da Ciência do Solo brasileira desde seu início, descrevendo sua situação atual e delineando oportunidades e desafios para as próximas décadas. A agronomia surgiu no País como uma subárea da botânica no início do século XIX e se aproximou da química, buscando o status de ciência. Dessa aproximação surgiu a química agrícola, ainda em meados desse século, dando origem a um dos ramos da Ciência do Solo: a edafologia. O outro ramo da Ciência do Solo (pedologia) consolidou-se como conhecimento científico e foi aplicado no País em meados do século XX. Nesse período foi criada a Sociedade Brasileira de Ciência do Solo, englobando todo o conhecimento dos dois ramos e aglutinando todos os cientistas que trabalhavam na área. Com a criação dos programas de pós-graduação, 20 anos depois de fundada a SBCS, a Ciência do Solo brasileira entrou na era da modernidade, e o conhecimento gerado foi fundamental para que o País atingisse o patamar atual de produtividade agrícola. Com uma comunidade de 25 departamentos de solos, 15 programas de pós-graduação e um grande número de instituições de pesquisa e de transferência de tecnologia, os cientistas de solo viabilizam soluções para o crescimento sustentável, gerando, adaptando e transferindo tecnologias em benefício do País. O solo e o conhecimento gerado pelos membros da SBCS contribuíram significativamente para que o Brasil chegasse à condição de agricultura tropical mais competitiva do planeta. Nas próximas décadas, a Ciência do Solo continuará no centro de discussão para a produção de alimentos, fibras e conservação ambiental, mas também será essencial e estratégica para assuntos como a qualidade da água, o combate à pobreza e a produção de fontes renováveis de energia.
    Keywords: Edaphology ; Pedology ; Brazilian Soil Science Society ; Retrospective And Perspective ; Edafologia ; Pedologia ; Sociedade Brasileira De Ciência Do Solo ; Retrospectivas E Perspectivas
    ISSN: 0100-0683
    Source: AGRIS (Food and Agriculture Organization of the United Nations)
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    In: Soil Science, 2009, Vol.174(8), pp.456-465
    Description: With rising ambient temperature and atmospheric carbon dioxide levels, there is an urgent need to monitor soil carbon stocks over large regions of the earth. Near-infrared diffuse reflectance sensing (NIRS) of soils, using satellite- or airplane-based instruments, is increasingly regarded as a potential method of choice for this purpose. Considerable research has been devoted to NIRS in the last few years, but this research has been generally restricted to sieved air-dried soils analyzed under laboratory conditions. For NIRS to be useful for the estimation of soil carbon stocks in the field, a technique must be developed to account, among other things, for the presence of moisture in the surface layer of soils. In this context, a first objective of the research described in this article was to determine whether, for three soils with contrasting characteristics, a simple constant proportionality factor relates NIR spectra obtained at different moisture contents, and whether there is relative constancy of this proportionality factor among soils, suggesting the possibility of a practical strategy to correct NIR spectra for soil moisture. A second objective of the research was to use ratio and derivative analysis to identify portions of NIR spectra that appear least affected by moisture content and on which a determination of other parameters such as organic matter content could be based. Because constant proportionality of the spectra at different moisture contents seems elusive, at best, the most significant result obtained is the identification of specific wavelength ranges in the NIR spectra, at 800 to 1400 nm, 1600 to 1700 nm, 2100 to 2200 nm, and 2300 to 2500 nm, where the first derivative of the spectra seems independent of the moisture content of the soil samples. This observation suggests that an operational method could be developed, focused on these wavelength intervals, to obtain moisture-independent estimates of a range of soil parameters under field conditions.
    Keywords: Temperature ; Carbon Dioxide ; Soil Sciences ; Effects ; Soils ; Moisture Content;
    ISSN: 0038-075X
    E-ISSN: 15389243
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: Vadose Zone Journal, 2004, Vol.3(1), p.262
    Description: As a result of Cryptosporidium parvum in drinking water, several outbreaks of cryptosporidiosis have occurred in the last 10 yr. Although it is generally believed that movement of pathogens through the soil is minimal, recent research has shown that appreciable numbers of C. parvum oocysts may be transported via preferential or fingered flow to groundwater. The objective of the present research was to further investigate and model the transport of oocysts through preferential flow paths in the vadose zone under a "worst-case" scenario. This was studied by adding calves feces containing C. parvum oocysts with a Cl- tracer to undisturbed silt loam columns and disturbed sand columns during a simulated steady-state rain. The sand columns exhibited preferential flow in the form of fingers whereas macropore flow occurred in the undisturbed cores. In the columns with fingered flow, oocysts and Cl were transported rapidly with the same velocity through the columns. Although only 14 to 86% of the amount applied, the number of oocysts transported across the columns was several orders of magnitude above an infective dose. The macropore columns had only a very limited breakthrough of oocysts, which appeared several pore volumes after the Cl broke through initially. A simulation model for the transport of oocysts via preferential flow was developed on the basis of an existing preferential flow model for nonadsorbing solutes, with addition of a first-order sink term for adsorbance of the C. parvum to the air-water-solid (AWS) interfaces, and with velocity and dispersivity parameters derived from Cl- transport. The breakthrough of C. parvum oocysts could be described realistically for the sand columns. However, the model could not describe oocyst transport in the columns with macropores. ; Includes references
    Keywords: Soil Transport Processes ; Sand ; Vadose Zone ; Soil Pollution ; Mathematical Models ; Simulation Models ; Silt Loam Soils ; Preferential Flow ; Oocysts ; Feces ; Calves ; Cryptosporidium Parvum;
    ISSN: Vadose Zone Journal
    E-ISSN: 1539-1663
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages