Schwendenmann, Luitgard

[["dc.bibliographiccitation.firstpage","73"],["dc.bibliographiccitation.issue","1-3"],["dc.bibliographiccitation.journal","Biogeochemistry"],["dc.bibliographiccitation.lastpage","85"],["dc.bibliographiccitation.volume","96"],["dc.contributor.author","Oxmann, Julian F."],["dc.contributor.author","Schwendenmann, Luitgard"],["dc.contributor.author","Lara, Ruben Jose"],["dc.date.accessioned","2018-11-07T11:21:17Z"],["dc.date.available","2018-11-07T11:21:17Z"],["dc.date.issued","2009"],["dc.description.abstract","Sediment reduction is frequently proposed to increase available phosphorus (P) but several studies found also decreases. Another important factor for P liberation is the pH. We investigated the relative importance of Eh and pH on P cycling in reforested mangroves. Sediment P compounds, pH and Eh were analysed over depth along five transects of two areas in the Saigon River Delta and compared with leaf P levels. A three-dimensional spatial approach was used to investigate pH and Eh effects on P compound distribution at different sediment depth and locate layers of predominant P uptake. Along an inundation gradient, submergence durations of 254 to 2 days per year caused a large Eh gradient within the top 20 cm, whereas Eh response was small within 20-45 cm depth. At individual layers, a correlation between Eh and Al/Fe-P was only found in the upper depth interval (0-20 cm). No significant effect of Eh or Al/Fe-P on Morgan-P (available P) was detected. Minor effects on P composition changes by the Eh were caused through generally strongly reduced sediment at deeper layers (> 20 cm). In contrast, pH variations produced extreme differences in both, Ca-P and available P content at layers of apparently predominant P uptake (> 20 cm). As available P was correlated with Ca-P (p < 0.001), leaf P (p < 0.001) and pH (non linear correlation) it is likely that the pH sensitive Ca-P fraction is a more effective source for mangrove tree growth than Al/Fe-P. The predominant pH effect on P uptake within these reforested mangroves differs from a proposed reduction-governed P cycling in wetlands."],["dc.description.sponsorship","German Research Foundation"],["dc.identifier.doi","10.1007/s10533-009-9345-5"],["dc.identifier.isi","000270280500005"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?goescholar/3579"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/55739"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1573-515X"],["dc.relation.issn","0168-2563"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Interactions among phosphorus, pH and Eh in reforested mangroves, Vietnam: a three-dimensional spatial analysis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","225"],["dc.bibliographiccitation.issue","1-2"],["dc.bibliographiccitation.journal","Plant and Soil"],["dc.bibliographiccitation.lastpage","241"],["dc.bibliographiccitation.volume","326"],["dc.contributor.author","Oxmann, Julian F."],["dc.contributor.author","Pham, Q. H."],["dc.contributor.author","Schwendenmann, Luitgard"],["dc.contributor.author","Stellman, J. M."],["dc.contributor.author","Lara, Ruben Jose"],["dc.date.accessioned","2018-11-07T08:48:28Z"],["dc.date.available","2018-11-07T08:48:28Z"],["dc.date.issued","2010"],["dc.description.abstract","Sediment physicochemical properties most likely control the reforestation success on degraded mangrove sites. Our objectives were (1) to determine the nutritional status of reforested mangrove stands; (2) to investigate the effects of the redox potential (Eh) and pH on phosphorus (P) and nitrogen (N) cycling; and (3) to assess the effect of pH on P speciation. Five transects were studied in replanted stands of the Saigon River Delta, Vietnam. Spatial gradients of sediment Eh and pH were affected by the tidal regime and pyrite oxidation. Sediment Al/Fe-P correlated with Eh or pH, depending on the sediment layer, whereas Ca-P, Morgan-P (available P) and leaf P were influenced by the pH. The highest concentrations of Al/Fe-P were recorded at pH 6.5 probably due to adsorption effects. Sediment Ca-P increased strongly at pH below 4 and above 6, reflecting the different pH-dependent solubilities of individual Ca-P mineral species as shown by a newly developed method for P species quantification. A strong increase of available P and leaf P above pH 6, and positive correlations of available P vs Ca-P (P < 0.001) and leaf P (P = 0.004) suggest that the Morgan's reagent for available P determination solubilizes mainly thermodynamically less stable Ca-P compounds, which seem to fuel P plant uptake. Since foliar and sediment N:P ratios were influenced mainly by pH, shifts in pH likely cause limitation transitions. Overall, sediment pH rather than Eh was found to control the nutrient status."],["dc.description.sponsorship","German - Vietnamese collaboration; German Research Foundation"],["dc.identifier.doi","10.1007/s11104-009-0003-4"],["dc.identifier.isi","000272850200018"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/6812"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/21216"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1573-5036"],["dc.relation.issn","0032-079X"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Mangrove reforestation in Vietnam: the effect of sediment physicochemical properties on nutrient cycling"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]