Acidic Soil (acidic + soil)

Distribution by Scientific Domains
Life Sciences50%
Earth and Environmental Science50%

Selected Abstracts

Adaptation to nickel spiking of bacterial communities in neocaledonian soils

ENVIRONMENTAL MICROBIOLOGY, Issue 1 2003
Marina Héry
Summary Adaptation to nickel of bacterial communities of two extreme neocaledonian soils (an ultramafic soil and an acidic soil) was investigated by nickel spiking and compared with adaptation in a non-neocaledonian soil used as reference. Soil microcosms were amended with nickel chloride (NiCl2), and bacterial community structure was analysed with the ribosomal intergenic spacer analysis (RISA) technique. Then, bacterial populations that respond to nickel stress were identified by cloning and sequencing. In the ultramafic soil, a shift occurred on day zero on the assay profiles and consisted of the emergence of a bacterial group closely related to the Ralstonia/Oxalobacter/Burkholderia group. It is hypothesized that NiCl2 had a physico-chemical impact on soil structure. Fourteen days after nickel spiking, another shift occurred in the two soils that concerned a bacterial group belonging to the Actinomycete group. Only a few changes occurred in the bacterial community structure of the neocaledonian soils compared with those of the reference soil, which is more affected by nickel spiking. These results suggest that neocaledonian soil bacteria are particularly well adapted to nickel. [source]

Effects of the herbicide hexazinone on nutrient cycling in a low-pH blueberry soil

ENVIRONMENTAL TOXICOLOGY, Issue 2 2004
D. M. Vienneau
Abstract The herbicide hexazinone was applied as the commercial formulation Velpar® L at field-rate (FR) concentrations of FR (14.77 ,g ai g,1), FR×5 (73.85 ,g ai g,1), FR×10 (147.70 ,g ai g,1), FR×50 (738.50 ,g ai g,1), and FR×100 (1477.00 ,g ai g,1) to acidic soil, pH 4.12, taken from a lowbush blueberry field. Hexazinone was tested for inhibitory effects on various transformations of the nitrogen cycle and soil respiration. Nitrogen fixation was unaffected by hexazinone levels up to FR×100 following a 4-week incubation period. Ammonification was initially inhibited by all levels of hexazinone, but after 4 weeks, ammonification in all treatment systems was equal to or greater than the control. Nitrification was more sensitive to hexazinone; however, application at a field-rate level caused no inhibition. Inhibitory effects were noted above FR after a 2-month endpoint analysis and above FR×5 after a 6-month endpoint analysis. Hexazinone concentrations up to and including FR×100 stimulated denitrification. Soil respiration was also stimulated over a 3-week period when applied at a level up to 100 times the recommended field rate. In general, it was found that when applied at the recommended field application rate, hexazinone does not adversely affect the nitrogen cycle or soil respiration in acidic lowbush blueberry soils. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 115,122, 2004 [source]

Growth response of the bacterial community to pH in soils differing in pH

FEMS MICROBIOLOGY ECOLOGY, Issue 1 2010
David Fernández-Calviño
Abstract The effect of pH on the instantaneous growth of soil bacterial communities was studied in five soils with different pH (4.5,7.8) using leucine (Leu) and thymidine (TdR) incorporation. The pH dependency of bacterial growth was modelled using three different unimodal functions, and the pHopt for growth and the pH range in which growth was >50% of the optimal growth were compared. Leu and TdR incorporation yielded very similar results. The best fits were obtained using a third-degree polynomial function and the cardinal pH model. However, a simple second-degree function was adequate in most cases, yielding very similar pHopt values to the other two models. Bacterial growth was highly influenced by pH, showing optimum growth at a pH related to the soil pH. The lowest pHopt was found in the most acidic soil and the highest pHopt in the soil with the highest pH. The pHopt for bacterial growth was close to the soil pH measured in water, but higher (0.7,2.1 units) than the pH measured with 0.1 M KCl. The pH range in which bacterial growth was >50% of that at optimum was, on average, 1.7 units below and above the optimum pH. [source]

The effect of nitrogen fertilization on fungistatic phenolic compounds in roots of beech (Fagus sylvatica) and Norway spruce (Picea abies)

FOREST PATHOLOGY, Issue 4 2005
L. Tomova
Summary The effect of nitrogen fertilization on fungistatic phenolic compounds in fine roots of beech and Norway spruce growing in afforestation plots was analysed. The plots were situated at two sites in Switzerland on acidic soil with low base saturation. For 9 years, the trees have been treated with dry ammonium nitrate to give 0, 10, 20, 40, 80, 160 kg N ha,1 year,1, respectively. The phenolic compounds responded differently to fertilization. Fine roots of beech showed a significant decrease of (,)-epicatechin and piceatannol with increasing nitrogen fertilization. The concentration of protocatechuic acid was increased with fertilization. Roots of fertilized Norway spruce showed significantly decreased concentrations of 4-hydroxyacetophenone and piceatannol. The mycelial growth of three isolates each of Heterobasidion annosum s.l. and Cylindrocarpon destructans was tested on agar media containing various phenolic compounds in concentrations found in fine roots of Norway spruce (Picea abies) and beech (Fagus sylvatica). All three H. annosum isolates were inhibited by p-coumaric acid and (,)-epicatechin. Two isolates were inhibited by another four phenolic compounds (p-hydroxybenzoic acid, 4-hydroxyacetophenone, piceatannol and protocatechuic acid), one by (+)-catechin. Two of three C. destructans isolates were inhibited by all phenolic compounds except for (+)-catechin which affected only one isolate, one isolate did not respond at all. Résumé L'effet d'une fertilisation azotée sur les composés phénoliques fongistatiques des racines fines de Hêtre (Fagus sylvatica) et d'Epicea (Picea abies) a été analysé dans des parcelles de reboisement. Ces parcelles sont situées dans deux localités de Suisse sur sol acide, avec un faible taux de saturation en bases. Pendant neuf ans, les arbres ont été traités par apports secs de nitrate d'ammonium à raison de 0, 10, 20, 40, 80, 160 kg N par hectare et par an, respectivement. La réponse des composés phénoliques à la fertilisation est variable. Les racines fines de hêtres ont montré une baisse significative d'épicatèchine (,) et de piceatannol avec l'augmentation de la fertilisation azotée. Les concentrations d'acide protocatéchique ont augmenté avec la fertilisation. Les racines d'épicèas fertilisés ont montré une baisse significative des concentrations de 4-hydroxyacétophénone et de piceatannol. La croissance mycélienne de trois isolats de chacune des espèces H .annosum s.l. et Cylindrocarpon destructans a été testée sur milieu agar contenant les différents composés phénoliques aux concentrations trouvées dans les racines fines d'épicèas (Picea abies) et de hêtres (Fagus sylvatica). Les trois isolats d'Heterobasidion annosum s.l. ont été inhibés par l'acide p-coumarique et l'épicatèchine (,). Deux isolats ont été inhibés par quatre autres composés phénoliques (acide p-hydroxybenzoïque, 4-hydroxyacétophénone, piceatannol et acide protocatéchique) et un par la catéchine (+). Deux des trois isolats de Cylindrocarpon destructans ont été inhibés par tous les composés phénoliques à l'exception de la catéchine (+) pour l'un des deux, le dernier isolat ne répondant à aucun composé. Zusammenfassung In einer Aufforstungs-Versuchsfläche wurde der Einfluss einer Stickstoffdüngung auf die fungistatischen phenolischen Verbindungen in Feinwurzeln von jungen Buchen und Fichten untersucht. Die Versuchsflächen befanden sich an zwei Standorten in der Schweiz mit sauren, basenarmen Bodenverhältnissen. Die Bäume wurden über neun Jahre mit 0, 10, 20, 40, 80 und 160 kg N ha,1 a,1 in Form von Ammoniumnitrat gedüngt. Die phenolischen Verbindungen reagierten unterschiedlich auf die Düngung. Die Feinwurzeln von Buchen zeigten mit zunehmender Stickstoffdüngung eine signifikante Abnahme von (,) Epicatechin und Piceatannol, während die Konzentration von Protocatechinsäure durch die Düngung erhöht wurde. Die Feinwurzeln gedüngter Fichten wiesen ebenfalls signifikant tiefere Konzentrationen von 4-Hydroyacetophenon und Piceatannol auf. In in-vitro-Tests wurde das Myzelwachstum von allen drei geprüften Isolaten von Heterobasidion annosum s. l. durch die in den Wurzeln gefundenen Konzentrationen von p-Coumarinsäure und (,)Epicatechin gehemmt. Zwei Pilzisolate zeigten zudem eine Hemmung durch vier weitere in den Wurzeln gefundene phenolische Verbindungen, nämlich p-Hydroxybenzoesäure, 4-Hydroxyacetophenon, Piceatannol und Protocatechinsäure, und eines wurde auch durch (+)-Catechin gehemmt. Bei zwei von drei geprüften Isolaten von Cylindrocarpon destructans wurde das Myzelwachstum durch alle untersuchten phenolischen Verbindungen gehemmt, mit Ausnahme von (+)-Catechin, welches sich nur auf ein Isolat negativ auswirkte. Ein Isolat von C. destructans reagierte auf keine der genannten Substanzen. [source]

Influence of Tithonia diversifolia and triple superphosphate on dissolution and effectiveness of phosphate rock in acidic soil

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 5 2006
Isaac Savini
Abstract An incubation and a pot experiment were conducted to evaluate the dissolution and agronomic effectiveness of a less reactive phosphate rock, Busumbu soft ore (BPR), in an Oxisol in Kenya. Resin (anion and anion + cation)-extractable P and sequentially extracted P with 0.5 M NaHCO3, 0.1 M NaOH, and 1 M HCl were analyzed. Dissolution was determined from the increase in anion resin (AER),, NaHCO3 -, and NaOH-extractable P in soil amended with PR compared with the control soil. Where P was applied, resin P significantly increased above the no-P treatment. Busumbu-PR solubility was low and did not increase significantly in 16 weeks. Anion + cation (ACER)-extractable P was generally greater than AER-P. The difference was greater for PR than for triple superphosphate (TSP). The ACER extraction may be a better estimate of plant P availability, particularly when poorly soluble P sources are used. Addition of P fertilizers alone or in combination with Tithonia diversifolia (TSP, BPR, TSP + Tithonia, and BPR + Tithonia) increased the concentration of labile inorganic P pools (NaHCO3 - and NaOH-Pi). Cumulative evolved CO2 was significantly correlated with cumulative N mineralized from Tithonia (r, 0.51, p < 0.05). Decrease in pH caused NH -N accumulation while NO -N remained low where Tithonia was incorporated at all sampling times. However, when pH was increased, NH -N declined with a corresponding rise in NO -N. Tithonia significantly depressed soil exchangeable acidity relative to control with time. A significant increase (p < 0.05) was observed for P uptake but not dry-mass production in maize where BPR was applied. The variations in yield and P uptake due to source and rates of application were statistically significant. At any given P rate, highest yields were obtained with Tithonia alone. Combination of Busumbu PR with TSP or Tithonia did not enhance the effectiveness of the PR. The poor dissolution and plant P uptake of BPR may be related to the high Fe content in the PR material. [source]

Total and soluble fluorine concentrations in relation to properties of soils in New Zealand

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2006
P. Loganathan
Summary Soil fluorine (F) concentrations continue to increase in agricultural soils receiving regular applications of phosphatic fertilizer. Continued accumulation of soil F poses a risk to grazing ruminants and may pose a future risk to groundwater quality. This paper examines the range of total F (Ft) concentrations and forms of soluble F species and their relationship to selected soil properties in New Zealand agricultural soils. The Ft and soluble F (soil F extracted with water (Fwater) and 0.01 m KCl (FKCl)) concentrations in 27 soil samples (0,75 mm depth) taken from predominantly pasture sites in the North and South Islands of New Zealand were much less than those reported in the literature for sites contaminated with F from industry. The Ft concentrations ranged from 212 to 617 µg F g,1 soil. The F-toxicity risk to grazing animals in farms at these sites through soil ingestion is small at present, but farms with very large Ft concentrations (i.e. > 500 µg F g,1) need to adopt suitable grazing and fertilizer management practices to avoid future F-toxicity risk. The Ft concentration had very strong positive correlations with both total soil P and total soil Cd concentrations, reflecting the link between P fertilizer use and F accumulation in the soils. It also had significant positive correlations with organic matter and amorphous Al oxides contents, indicating that F is strongly bound to Al polymers adsorbed to organic matter and amorphous Al oxides. The Fwater and FKCl concentrations and free F, ion concentrations in water (F,water) and 0.01 m KCl (F,KCl) extracts were generally two and three orders of magnitude, respectively, less than the Ft concentrations and were much less than the concentrations considered phytotoxic. The Fwater and FKCl concentrations were positively related to soil organic matter content and negatively related to soil pH. Regression models relating Fwater and FKCl concentrations to soil organic matter content and soil pH suggest that F can be very soluble in extremely acidic soils (pH(water) < 4.9) with large organic matter contents and therefore F potentially may contaminate groundwater if these soils are also coarse-textured and the water table is shallow. [source]

Estimation of the phosphorus sorption capacity of acidic soils in Ireland

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2001
R. O. Maguire
Summary The test for the degree of phosphorus (P) saturation (DPS) of soils is used in northwest Europe to estimate the potential of P loss from soil to water. It expresses the historic sorption of P by soil as a percentage of the soil's P sorption capacity (PSC), which is taken to be , (Alox + Feox), where Alox and Feox are the amounts of aluminium and iron extracted by a single extraction of oxalate. All quantities are measured as mmol kg soil,1, and a value of 0.5 is commonly used for the scaling factor , in this equation. Historic or previously sorbed P is taken to be the quantity of P extracted by oxalate (Pox) so that DPS = Pox/PSC. The relation between PSC and Alox, Feox and Pox was determined for 37 soil samples from Northern Ireland with relatively large clay and organic matter contents. Sorption of P, measured over 252 days, was strongly correlated with the amounts of Alox and Feox extracted, but there was also a negative correlation with Pox. When PSC was calculated as the sum of the measured sorption after 252 days and Pox, the multiple regression of PSC on Alox and Feox gave the equation PSC = 36.6 + 0.61 Alox+,0.31 Feox with a coefficient of determination (R2) of 0.92. The regression intercept of 36.6 was significantly greater than zero. The 95% confidence limits for the regression coefficients of Alox and Feox did not overlap, indicating a significantly larger regression coefficient of P sorption on Alox than on Feox. When loss on ignition was employed as an additional variable in the multiple regression of PSC on Alox and Feox, it was positively correlated with PSC. Although the regression coefficient for loss on ignition was statistically significant (P <,0.001), the impact of this variable was small as its inclusion in the multiple regression increased R2 by only 0.028. Values of P sorption measured over 252 days were on average 2.75 (range 2.0,3.8) times greater than an overnight index of P sorption. Measures of DPS were less well correlated with water-soluble P than either the Olsen or Morgan tests for P in soil. [source]

Piceoxylon pseudotsugae GOTHAN emend.

FEDDES REPERTORIUM, Issue 1 2001
Deutschland, VAN DER BURGH aus dem Obermiozän von Ottendorf-Okrilla bei Dresden
1987 konnte im Westteil der Kiesgrube Ottendorf-Okrilla (höheres Obermiozän) aus Tonen mit kohligen Schmitzen ein 1,14 m langer Stammrest geborgen werden. Er wird als Piceoxylon pseudotsugae Gothan 1906 emend, van der Burgh (1973) bestimmt. Das fossile Holz zeigt große Ähnlichkeit mit der heute noch im pazifischen Nordamerika beheimateten Pseudotsuga menziesii (Mirb.) Franco. Xylotomische Nachweise dieser Art sind bis heute nur wenige bekannt. Sie stammen aus Nordamerika, Deutschland (Rheinland), Österreich und Slask (Schlesien/Polen). Zu der anatomischen Beschreibung des Holzes wird die Ökologie der rezenten und die Paläookologie der fossilen Pseudotsuga diskutiert. Piceoxylon pseudotsugae Gothan emend. Van der Burgh from the Upper Miocene from Ottendorf-Okrilla near Dresden, Germany. A fossil wood, collected in Ottendorf-Okrilla by H. Kubasch, Kamenz, is described in this paper. It is identified by the first author as Piceoxylon pseudotsugae Gothan 1906 emend, van der Burgh 1973 because of its clear spiral thickenings in the tracheids (early and late wood) together with vertical and horizontal resin ducts. Tertiary wood assigned to this species is up till now only known from a few localities in North America and Europe (Rheinland/Germany, Austria, Silesia/Poland). The recent comparable species, Pseudotsuga menziesii (Mirb.) Franco, is known from a wide variety of localities in North America, with a very variable range concerning temperature. It is a tree of well drained, slightly acidic soils, preferably on sedimentary rocks with a volcanic or glacial origin. In the Tertiary of Europe this tree is also known from brown coal deposits. Therefore, for the Tertiary species a habitat in swamp environment must be added. [source]

PCR profiling of ammonia-oxidizer communities in acidic soils subjected to nitrogen and sulphur deposition

FEMS MICROBIOLOGY ECOLOGY, Issue 2 2007
Christoph Stephan Schmidt
Abstract Communities of ammonia-oxidizing bacteria (AOB) were characterized in two acidic soil sites experimentally subjected to varying levels of nitrogen and sulphur deposition. The sites were an acidic spruce forest soil in Deepsyke, Southern Scotland, with low background deposition, and a nitrogen-saturated upland grass heath in Pwllpeiran, North Wales. Betaproteobacterial ammonia-oxidizer 16S rRNA and ammonia monooxygenase (amoA) genes were analysed by cloning, sequencing and denaturing gradient gel electrophoresis (DGGE). DGGE profiles of amoA and 16S rRNA gene fragments from Deepsyke soil in 2002 indicated no effect of nitrogen deposition on AOB communities, which contained both Nitrosomonas europaea and Nitrosospira. In 2003, only Nitrosospira could be detected, and no amoA sequences could be retrieved. These results indicate a decrease in the relative abundance of AOB from the year 2002 to 2003 in Deepsyke soil, which may be the result of the exceptionally low rainfall in spring 2003. Nitrosospira -related sequences from Deepsyke soil grouped in all clusters, including cluster 1, which typically contains only sequences from marine environments. In Pwllpeiran soil, 16S rRNA gene libraries were dominated by nonammonia oxidizers and no amoA sequences were detectable. This indicates that autotrophic AOB play only a minor role in these soils even at high nitrogen deposition. [source]

Costing yield loss from acidity, sodicity and dryland salinity to Australian agriculture

LAND DEGRADATION AND DEVELOPMENT, Issue 5 2005
S. Hajkowicz
Abstract Salinity, sodicity and acidity are three major soil constraints that limit crop and pasture yields in Australia. In this paper estimates are made of the potential benefits arising from their treatment by measuring and mapping their impact on agricultural profit. This is achieved by estimating the increase in profit for Australia's main commodities that would occur if the three soil constraints were costlessly ameliorated. These estimates reveal the upper achievable limit on investment returns. They are also indicative of each soil constraint's economic significance to Australian agriculture. It was found that costless removal of salinity would increase annual profits by A$187 million, sodicity by A$1034·6 million and acidity by A$1584·5 million. This equates to 2·9,per,cent, 15·8,per,cent and 24·2,per,cent of total net economic return. It was also found that worsening salinity extent and severity over 2000,2020 has a present value of A$496,A$712 million. Although soil salinity is currently the focus of much public attention, this analysis suggests that from a production viewpoint the correction of sodic and acidic soils may create greater private economic benefit. Opportunities vary considerably among industries. In particular, there is considerable opportunity for the horticultural and viticultural sector to address acidity issues. Whether gross benefits translate into net benefits is a complex question requiring access to context and location-specific information. Copyright © 2005 John Wiley & Sons, Ltd. [source]