For the first time,three closely related international conference series on environment and health,International Symposium on Environment and Health(ISEH),International Conference on Environmental Pollution and Health...For the first time,three closely related international conference series on environment and health,International Symposium on Environment and Health(ISEH),International Conference on Environmental Pollution and Health(ICEPH)and Environmental Symposium on Environmental Geochemis-try(ISEG),came together as a joint conference(https://www.universityofgalway.ie/iseh-iceph),which was successfully held on campus of University of Galway,Ireland during August 11−18,2024(Figure 1).展开更多
Organic phosphorus （nonreactive E NRP） is a major component of P in sediments, but information about its chemical forms and dynamic transformation is limited. The chemical forms and dynamic behaviors of NRP in a sed...Organic phosphorus （nonreactive E NRP） is a major component of P in sediments, but information about its chemical forms and dynamic transformation is limited. The chemical forms and dynamic behaviors of NRP in a sediment profile from Lake Talhu, a freshwater and eutrophic lake in China, were investigated. Five forms of NRP in the sediments were extracted based on a chemical fractionation technique, including easily labile NRP （NaHCO3-NRP）, reactive metal oxide-bound NRP （HCl-NRP）, humic acid-associated NRP （NaOH-NRPnA）, fulvic acid-associated NRP （NaOH-NRPFA） and residual NRP （Res-TP）. There were notable transformations with increasing sediment depth from the labile NaHCOa-NRP and NaOH-NRP pools to the recalcitrant HCl-NRP and Res-TP pools, which caused the NRP to become increasingly recalcitrant as the early diagenetic processes proceeded. Further analyses showed that the relative changes in contents of organic matter and reactive Fe oxides in the sediment profile triggered a competition for binding NRP fractions and led to the transformation of NRP. The results highlighted the importance of abiotic processes in regulating the diagenesis of organic P and its stability in sediments.展开更多
The understanding of organic phosphorus（P） dynamics in sediments requires information on their species at the molecular level,but such information in sediment profiles is scarce.A sediment profile was selected from ...The understanding of organic phosphorus（P） dynamics in sediments requires information on their species at the molecular level,but such information in sediment profiles is scarce.A sediment profile was selected from a large eutrophic lake,Lake Taihu（China）,and organic P species in the sediments were detected using solution phosphorus-31 nuclear magnetic resonance spectroscopy（31 P NMR） following extraction of the sediments with a mixture of 0.25 mol/L NaOH and 50 mmol/L EDTA（NaOH-EDTA） solution.The results showed that P in the NaOH-EDTA extracts was mainly composed of orthophosphate,orthophosphate monoesters,phospholipids,DNA,and pyrophosphate.Concentrations of the major organic P compound groups and pyrophosphate showed a decreasing trend with the increase of depth.Their half-life times varied from 3 to 27 years,following the order of orthophosphate monoesters 〉 phospholipids DNA 〉 pyrophosphate.Principal component analysis revealed that the detected organic P species had binding phases similar to those of humic acid-associated organic P（NaOH-NRP HA）,a labile organic P pool that tends to transform to recalcitrant organic P pools as the early diagenetic processes proceed.This demonstrated that the depth attenuation of the organic P species could be partly attributed to their increasing immobilization by the sediment solids,while their degradation rates should be significantly lower than what were suggested in previous studies.展开更多
Sampling plays an important role in acquiring precise soil information required in modern agricultural production worldwide, which determines both the cost and quality of final soil mapping products. For sampling desi...Sampling plays an important role in acquiring precise soil information required in modern agricultural production worldwide, which determines both the cost and quality of final soil mapping products. For sampling design, it has been proposed possibile to transfer the relationships between kriging variance and sampling grid spacing from an area with existing information to other areas with similar soil-forming environments. However, this approach is challenged in practice because of two problems: i) different population vaxiograms among similar areas and ii) sampling errors in estimated variograms. This study evaluated the effects of these two problems on the transferability of the relationships between kriging variance and sampling grid spacing, by using spatial data simulated with three variograms and soil samples collected from four grasslands in Ireland with similar soil-forming environments. Results showed that the variograms suggested by different samples collected with the same grid spacing in the same or similar areas were different, leading to a range of mean kriging variance (MKV) for each grid spacing. With increasing grid spacing, the variation of MKV for a specific grid spacing increased and deviated more from the MKV generated using the population variograms. As a result, the spatial transferability of the relationships between kriging variance and grid spacing for sampling design was limited.展开更多
文摘For the first time,three closely related international conference series on environment and health,International Symposium on Environment and Health(ISEH),International Conference on Environmental Pollution and Health(ICEPH)and Environmental Symposium on Environmental Geochemis-try(ISEG),came together as a joint conference(https://www.universityofgalway.ie/iseh-iceph),which was successfully held on campus of University of Galway,Ireland during August 11−18,2024(Figure 1).
基金supported by the National Natural Scientific Foundation of China (No. 40871220,40730528)the Natural Scientific Foundation of Jiangsu Province,China (No. BK2010606)the Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences(No. NIGLAS2010KXJ01)
文摘Organic phosphorus （nonreactive E NRP） is a major component of P in sediments, but information about its chemical forms and dynamic transformation is limited. The chemical forms and dynamic behaviors of NRP in a sediment profile from Lake Talhu, a freshwater and eutrophic lake in China, were investigated. Five forms of NRP in the sediments were extracted based on a chemical fractionation technique, including easily labile NRP （NaHCO3-NRP）, reactive metal oxide-bound NRP （HCl-NRP）, humic acid-associated NRP （NaOH-NRPnA）, fulvic acid-associated NRP （NaOH-NRPFA） and residual NRP （Res-TP）. There were notable transformations with increasing sediment depth from the labile NaHCOa-NRP and NaOH-NRP pools to the recalcitrant HCl-NRP and Res-TP pools, which caused the NRP to become increasingly recalcitrant as the early diagenetic processes proceeded. Further analyses showed that the relative changes in contents of organic matter and reactive Fe oxides in the sediment profile triggered a competition for binding NRP fractions and led to the transformation of NRP. The results highlighted the importance of abiotic processes in regulating the diagenesis of organic P and its stability in sediments.
基金supported by the National Scientific Foundation of China (No. 40871220,40730528)the Natural Scientific Foundation of Jiangsu Province,China (No.BK2010606)the Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences (No. NIGLAS2010KXJ01)
文摘The understanding of organic phosphorus（P） dynamics in sediments requires information on their species at the molecular level,but such information in sediment profiles is scarce.A sediment profile was selected from a large eutrophic lake,Lake Taihu（China）,and organic P species in the sediments were detected using solution phosphorus-31 nuclear magnetic resonance spectroscopy（31 P NMR） following extraction of the sediments with a mixture of 0.25 mol/L NaOH and 50 mmol/L EDTA（NaOH-EDTA） solution.The results showed that P in the NaOH-EDTA extracts was mainly composed of orthophosphate,orthophosphate monoesters,phospholipids,DNA,and pyrophosphate.Concentrations of the major organic P compound groups and pyrophosphate showed a decreasing trend with the increase of depth.Their half-life times varied from 3 to 27 years,following the order of orthophosphate monoesters 〉 phospholipids DNA 〉 pyrophosphate.Principal component analysis revealed that the detected organic P species had binding phases similar to those of humic acid-associated organic P（NaOH-NRP HA）,a labile organic P pool that tends to transform to recalcitrant organic P pools as the early diagenetic processes proceed.This demonstrated that the depth attenuation of the organic P species could be partly attributed to their increasing immobilization by the sediment solids,while their degradation rates should be significantly lower than what were suggested in previous studies.
基金?nancially supported by the National Natural Science Foundation of China (Nos. 41541006 and 41771246)co-funded by Enterprise Ireland and the European Regional Development Fund (ERDF) under the National Strategic Reference Framework (NSRF) 2007–2013
文摘Sampling plays an important role in acquiring precise soil information required in modern agricultural production worldwide, which determines both the cost and quality of final soil mapping products. For sampling design, it has been proposed possibile to transfer the relationships between kriging variance and sampling grid spacing from an area with existing information to other areas with similar soil-forming environments. However, this approach is challenged in practice because of two problems: i) different population vaxiograms among similar areas and ii) sampling errors in estimated variograms. This study evaluated the effects of these two problems on the transferability of the relationships between kriging variance and sampling grid spacing, by using spatial data simulated with three variograms and soil samples collected from four grasslands in Ireland with similar soil-forming environments. Results showed that the variograms suggested by different samples collected with the same grid spacing in the same or similar areas were different, leading to a range of mean kriging variance (MKV) for each grid spacing. With increasing grid spacing, the variation of MKV for a specific grid spacing increased and deviated more from the MKV generated using the population variograms. As a result, the spatial transferability of the relationships between kriging variance and grid spacing for sampling design was limited.
