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
  • Soil Solution
Type of Medium
Language
Year
  • 1
    Language: English
    Description: Based on the differences of lupin and corn in Si requirement and their capacity to release organic acids for P mobilisation both plant species were compared in respect to As mobilisation and plant As uptake and release which is closely linked to P and Si nutrition. Plants were grown with and without P fertilization in an As contaminated floodplain soil in compartment systems which enabled temporally resolved sampling of soil solution with increasing distance from the root surface. Although no direct increase of P or AsV concentration in soil solution could be detected, lupins showed higher P and As uptake but lower root to shoot translocation of As compared to corn plants. Higher root As concentrations in lupins corresponded to higher AsIII concentration in soil solution which increased with time and corresponded to the recently demonstrated diffusion driven efflux of As in the form of AsIII via aquaglycerol channels. It is well established that AsV, the form of As initially present in the floodplain soil, is taken up via P transporters. Hence the higher As uptake of lupin is in line with previous results showing higher P uptake capacity per unit root length for lupin compared to corn. A lower capacity for As efflux in lupin as it was expected due to lower Si requirement of lupin compared to corn could not be demonstrated.
    Keywords: Element Toxicity and Remediation; arsenite efflux; arsenate; phosphorus; rhizosphere; soil solution; speciation
    Source: eScholarship
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Plant and Soil, 2013, Vol.371(1), pp.267-279
    Keywords: Exchangeable K ; Non-exchangeable K ; Subsoil ; Illite ; Soil solution ; Ca
    ISSN: 0032-079X
    E-ISSN: 1573-5036
    Source: Springer Science & Business Media B.V.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Plant and Soil, 2004, Vol.258(1), pp.307-327
    Description: Soil solution composition changes with time and distance from the root surface as a result of mass flow, diffusion, plant nutrient uptake and root exudation. A model system was designed, consisting of a root compartment separated from the bulk soil compartment by a nylon net (30 μm mesh size), which enabled independent measurements of the change of soil solution composition and soil water content with increasing distance from the root surface (nylon net). K + concentration in the rhizosphere soil solution decreased during the initial growth stage (12 days after planting, DAP). Thereafter K + accumulated with time, due to mass flow as the dominating process. The extend of K + accumulation depended on the initial fertiliser application. As K + concentrations in soil solution increase, not only as a result of transport exceeding uptake, but also as a result of decreasing soil water content, it is hypothesised that K concentration in soil solution is not the only trigger for the activity of K transporters in membranes, but ABA accumulation in roots induced by decreasing soil matric potentials may add to the regulation. A strong decrease of rhizosphere pH with time is observed as a result of H + efflux from the roots in order to maintain cation-anion balance. In addition the K + to Ca 2+ ratio was altered continuously during the growing period, which has an impact on Ca 2+ uptake and thus firmness of cell walls, apoplast pH, membrane integrity and activity of membrane transporters. The value of osmotic potential in the rhizosphere soil solution increased with time indicating decreasing soil water availability. Modelling approaches based on the data obtained with the system might help to fill in the time gaps caused by the low temporal resolution of soil solution sampling method.
    Keywords: K ; matric potential ; osmotic potential ; pH ; rhizosphere ; soil solution
    ISSN: 0032-079X
    E-ISSN: 1573-5036
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Plant and Soil, 1 October 2013, Vol.371(1/2), pp.267-279
    Description: Aims and background Release of 'non-exchangeable' potassium (K) from interlayers of illite is diffusioncontrolled and has been shown to depend on the solution concentration of Ê and other cations (Ca²⁺, Mg²⁺, NH₄⁺). Methods We analysed changes in soil solution concentrations of K and competing cations in situ at different distances from the root surface over time and related them to the transformation of illite, as revealed by X-ray diffraction, and chemical measures of differently bound K. Results and Conclusions Within 49 and 98 days, respectively, 6.4 and 14.4 % of the illite's total K was released upon contact with the root system. Mixed layered minerals increased from 33 (0 d) to 35 (49 d) to 40 % (98 d). Release of K from interlayers and the transformation of illite occurred at soil solution K concentrations close to the threshold of 80 µM suggested earlier. Concentrations of Ca and Mg increased with decreasing distance from the root surface, promoting the release of K. The NaBPh₄ method supposed to determine 'non-exchangeable' K extracted only 1/3 of the total K from illite.
    Keywords: Physical sciences -- Earth sciences -- Geology ; Biological sciences -- Agriculture -- Agricultural sciences ; Biological sciences -- Agriculture -- Agricultural sciences ; Biological sciences -- Agriculture -- Agricultural sciences ; Biological sciences -- Biology -- Botany ; Physical sciences -- Earth sciences -- Geology ; Physical sciences -- Chemistry -- Chemical elements ; Biological sciences -- Biology -- Botany ; Biological sciences -- Agriculture -- Agricultural sciences ; Physical sciences -- Earth sciences -- Geology
    ISSN: 0032079X
    E-ISSN: 15735036
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: Paddy and Water Environment, 2018, Vol.16(2), pp.243-252
    Description: Silicon (Si) mitigates abiotic and biotic stresses for rice plants ( Oryza sativa L.). Here, we test relationships between Si cycling, plant growth, and pest and fungal attacks in rice agroecosystems. We conducted a plot experiment on Si fertilization in a Southern Vietnamese paddy, where plant-available Si was inherently low. For two cropping seasons, we investigated the temporal dynamics of Si in soil solution, plant Si uptake, and the occurrence of leaf folders ( Cnaphalocrocis medinalis ) and rice blast caused by the fungus Magnaporthe oryzae . Silicon application increased Si concentrations in soil solutions collected in the field as expected from previous laboratory experiments. Soil solution Si concentrations were furthermore affected by Si uptake by plants and by recycling Si with rice straw ash. Silicon concentrations in rice leaves at tillering stage increased with increasing Si application. However, surprisingly, no relationship between Si in soil solution and Si concentration in straw at maturity stage was found. The occurrences of leaf folders and rice blast disease were mitigated by increased Si uptake. However, rice biomass production was not affected, probably because the biotic stress level was generally low. Our field data emphasize the importance of recycling crop residues in rice fields for the Si supply to plants, especially in regions with low Si availability. They furthermore show that under field conditions, the relationship between dissolved Si in soil solution and Si uptake by rice plants is not as straightforward as expected and thus needs to be further investigated.
    Keywords: Dissolved silicon ; Leaf folder ; Rice ; Rice blast ; Silicon fertilization
    ISSN: 1611-2490
    E-ISSN: 1611-2504
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Language: English
    In: Journal of Plant Nutrition and Soil Science, June 2004, Vol.167(3), pp.337-344
    Description: According to the biphasic model of growth response to salinity, growth is first reduced by a decrease in the soil osmotic potential (Ψ), , growth reduction is an effect of salt outside rather than inside the plant, and genotypes differing in salt resistance respond identically in this first phase. However, if genotypes differ in Na uptake as it has been described for the two maize cultivars Pioneer 3906 and Across 8023, this should result in differences in Na concentrations in the rhizosphere soil solution and thus in the concentration of salt outside the plant. It was the aim of the present investigation to test this hypothesis and to investigate the effect of such potential differences in soil Ψ caused by Na exclusion on plant water relations. Sodium exclusion at the root surface of intact plants growing in soil was investigated by sampling soil solution from the rhizosphere of two maize cultivars (Across 8023, Pioneer 3906). Plants were grown in a model system, consisting of a root compartment separated from the bulk soil compartment by a nylon net (30 μm mesh size), which enabled independent measurements of the change of soil solution composition and soil water content with increasing distance from the root surface (nylon net). Across 8023 accumulated higher amounts of sodium in the shoot compared to the excluder (Pioneer 3906). The lower Na uptake in the excluder was partly compensated by higher K uptake. Pioneer 3906 not only excluded sodium from the shoot but also restricted sodium uptake more efficiently from roots relative to Across 8023. This was reflected by higher Na concentrations in the rhizosphere soil solution of the excluder 34 days after planting (DAP). The difference in Na concentration in rhizosphere soil solution between cultivars was neither due to differences in transpiration and thus in mass flow, nor due to differences in actual soil water content. As the lower Na uptake of the excluder (Pioneer 3906) was only partly compensated by increased uptake of K, soil Ψ in the rhizosphere of the excluder was more negative compared to Across 8023. However, no significant negative effect of decreased soil Ψ on plant water relations (transpiration rate, leaf Ψ, leaf water potential, leaf area) could be detected. This may be explained by the fact that significant differences in soil Ψ between the two cultivars occurred only towards the end of the experiment (27 DAP, 34 DAP). Die Bedeutung der Fähigkeit, Natrium von der Aufnahme auszuschließen, für das osmotische Potential in der Rhizosphäre – Vergleich zweier Maissorten mit unterschiedlicher Na+‐Aufnahme Geht man beim Einfluss von Salz auf das Pflanzenwachstum vom Zweiphasen‐Modell aus, so wird das Wachstum zunächst durch das Absinken des osmotischen Potentials (Ψ) im Boden beeinträchtigt, d. h., durch Salz außerhalb der Pflanze. Genotypen mit unterschiedlicher Salzresistenz reagieren in dieser Phase identisch. Unterscheiden sich nun aber Genotypen in ihrer Na‐Aufnahme, wie dies für die beiden Maissorten Pioneer 3906 und Across 8023 beschrieben wurde, so sollte dies zu unterschiedlichen Na‐Konzentrationen in der Rhizosphärenbodenlösung führen und somit zu Unterschieden in der Konzentration von Salz außerhalb der Pflanze. Ziel der hier vorgestellten Untersuchungen war es, diese Hypothese zu prüfen sowie die Bedeutung solch potenzieller Unterschiede im Ψ der Bodenlösung, verursacht durch Na‐Ausschluss, für den Pflanzenwasserhaushalt zu untersuchen. Der Ausschluss von Natrium an der Wurzeloberfläche intakter Pflanzen wurde durch Gewinnung der Rizosphärenbodenlösung bei zwei verschiedenen Maissorten (Across 8023, Pioneer 3906) untersucht. Die Pflanzen wurden in einem Modellsystem, bestehend aus Wurzelkompartiment und Gesamtbodenkompartimenten, welche durch Nylonnetze (30 μm Maschengröße) voneinander getrennt waren, kultiviert. Die Veränderung der Bodenlösungszusammensetzung und die Änderung des Bodenwassergehaltes konnten unabhängig voneinander mit zunehmender Entfernung von der Wurzeloberfläche (= Nylonnetz) gemessen werden. Across 8023 akkumulierte größere Mengen an Natrium im Spross als der ,Excluder‘ Pioneer 3906. Die geringere Na‐Aufnahme beim ,Excluder‘ wurde partiell durch eine höhere K‐Aufnahme kompensiert. Pioneer 3906 schloss Natrium nicht nur vom Spross, sondern auch von der Wurzel effizienter aus als Across 8023. Dies spiegelte sich in einer höheren Na‐Konzentration in der Rhizosphärenbodenlösung beim ,Excluder‘ 34 Tage nach Pflanzung (DAP) wider. Die Unterschiede zwischen den beiden Maissorten in der Na‐Konzentration in der Rhizosphärenbodenlösung waren weder auf Unterschiede in der Transpiration und damit im Massenfluss, noch auf Unterschiede im aktuellen Bodenwassergehalt zurückzuführen. Da die geringere Na‐Aufnahme beim ,Excluder‘ nur teilweise durch eine höhere K‐Aufnahme kompensiert wurde, war Ψ der Rhizosphärenbodenlösung beim ,Excluder‘ negativer als bei Across 8023. Trotz dieser Unterschiede konnte kein Einfluss des negativeren Ψ auf Wasserhaushaltsparameter (Transpirationsrate, Ψ der Blätter, Blattwasserpotenzial, Blattfläche) festgestellt werden. Dies könnte darauf zurückzuführen sein, dass signifikante Unterschiede im Ψ der Rhizosphärenbodenlösung erst gegen Versuchsende auftraten (27 DAP, 34 DAP).
    Keywords: Excluder ; Potassium ; Sodium ; Maize ; Matric Potential ; Osmotic Potential ; Rhizosphere ; Salinity ; Soil Solution
    ISSN: 1436-8730
    E-ISSN: 1522-2624
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: Vadose Zone Journal, 2008, Vol.7(2), p.712
    Description: The transfer of nutrients and contaminants from bulk soil to roots and into plants depends on many plant and soil processes. The RhizoMath approach for modeling co-occurring processes in the rhizosphere, including speciation in the soil solution, is based on coupling the mathematical package MATLAB with the geochemical code PHREEQC. In addition to the built-in initialization module that performs calibration against experimental data, RhizoMath's greatest advantage is that different geochemical models (with and without charge balance) and geometries (planar and radial) are already included. Moreover, due to its graphical user interface, the tool can be applied without changing the source code or a complex input file. The model was verified using a benchmark and experimental data: (i) the initialization module was successfully applied to describe concentrations measured in soil solution samples; (ii) the theoretical problem "diffusion of K toward a single root" was used to demonstrate that the performance of applied numerical methods is comparable to other approaches; and (iii) for compartment system experiments involving more complex speciation, RhizoMath was able to describe the observed effects of citrate exudates on the simultaneous transport of arsenate and phosphate that compete for surface binding sites with each other and with other oxyanions such as citrate. ; In the special section: Vadose zone modeling. Includes references ; p. 712-720.
    Keywords: Soil Solution ; Arsenic ; Rhizosphere ; Mathematical Models ; Citric Acid ; Phosphorus ; Phosphates ; Simulation Models ; Root Exudates ; Soil Transport Processes ; Nutrients ; Potassium ; Chemical Speciation ; Geochemistry ; Rhizomath Model;
    ISSN: Vadose Zone Journal
    E-ISSN: 1539-1663
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: Journal of environmental quality, 2007, Vol.36(6), pp.1811-20
    Description: Arsenate (As V) is the predominant form of arsenic in soils under aerobic conditions and competes with the major plant nutrient phosphorus (P) in the form of phosphate (PV) not only for sorption sites on mineral surfaces in soil but also for root membrane transporters. Plants have evolved several mechanisms for the mobilization of PV in soils in response to P deficiency, such as the release of organic anions and protons. The aim of the present study was to test whether these mechanisms result in a simultaneous mobilization of arsenate and what would be the consequences for As transfer from soil to plant. The compartment system approach with Zea mays as model crop was chosen as an experimental setup. The system is equipped with micro suction cups and allowed us to investigate processes occurring in the vicinity of roots. As a case study, an artificial quartz substrate with well defined soil physical properties was fertilized, spiked with As V, and amended with increasing amounts of goethite (0, 1, and 4 g kg(-1) in treatments G-0, G-1, and G-4, respectively). The addition of goethite alleviated the As V-induced growth reduction and reduced As V transfer from the substrate to the plant but induced P deficiency at the same time. When low amounts of goethite (1 g kg(-1)) were added, plants mobilized PV but not As V, which might be related to differences in surface complexation reported for PV and As V. No mobilization of PV or As V was observed with the addition of higher amounts of goethite, probably because of decreasing competition between organic anions, PV, and As V for binding sites.
    Keywords: Arsenates -- Metabolism ; Iron Compounds -- Metabolism ; Phosphates -- Metabolism ; Plant Roots -- Metabolism
    ISSN: 0047-2425
    E-ISSN: 15372537
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Text Resource
    Text Resource
    Universitäts- und Landesbibliothek Sachsen-Anhalt
    Description: Kenntnisse der Eisen(Fe)dynamik sind wesentlich für das Verständnis von Redoxreaktionen und biogeochemischen Prozessen in Böden. Ziel der Arbeit war es, Langzeitauswirkungen von Redoxschwankungen auf Fe-Mineraltransformationen aufzuklären. Entlang einer Chronosequenz von 100, 700 und 2000 Jahre alten Nassreisböden und nicht-bewässerter Ackerböden wurden Veränderungen im Mineralbestanduntersucht. In-situ Verwitterungsversuche mit Testmineralen beleuchteten ergänzend die Kurzzeitauswirkungen von Nassreisanbau auf Mineraltransformationen. In Feldversuchen wurden die Redoxdynamik und die Zusammensetzung der Bodenlösung in Relation zur Nutzungsdauer und damit einhergehenden Mineraltransformationen untersucht. Nassreisanbau führte zur Ausbildung unterschiedlicher Transformationsmilieus in Ober- und Unterboden und deutlicher Tiefenprofilierung mit andauernder Nutzung und steigender Anzahl an Redoxzyklen. Redoxdynamik und Zusammensetzung der Bodenlösung spiegelten dies zum Teil wider.... ; Knowledge on iron (Fe) mineral dynamics in soils is essential for understanding redox reactions and biogeochemical processes. The main objective of the thesis was to elucidate Fe mineral transformations as evoked by long-term redox cycles. Changes in the mineral assemblage were studied along a chronosequence of paddy soils used for 100, 700 and 2000 years of irrigated rice cultivation and their non-irrigated counterparts. Short term transformations were tracked by in situ weathering experiments with test minerals. Field experiments addressed redox dynamics and subsequent changes in the composition of the soil solution as related to time of paddy cultivation and concomitant mineral transformations. Different Fe mineral transforming environments established in paddy top- and subsoils. Resulting profile differentiation became increasingly distinct with time under paddy management and increasing numbers of redox cycles. Redox dynamics and soil solutions partly mirrored these observations....
    Keywords: Nassreisanbau; Bodenprofildifferenzierung; Mineraltransformationen; Fe-Oxide; Fe-Haltige Tonminerale; Redoxprozesse; Bodenlösung; Mößbauer-Spektroskopie ; Paddy Management; Soil Profile Differentiation; Mineral Transformations; Fe Oxides; Fe-Bearing Silicates; Redox Processes; Soil Solution; Mössbauer Spectroscopy ; Ddc::600 Technik, Medizin, Angewandte Wissenschaften::630 Landwirtschaft::630 Landwirtschaft Und Verwandte Bereiche
    Source: DataCite
    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