Measurement of Acid Volatile Sulphide and Simultaneously Extracted Metals in Sediment from Lake Albufera (Valencia, Spain)

Lake Albufera (Valencia, Spain) is part of a legally protected wetland of international importance. However, it has deteriorated as a result of urban, industrial, and farming pollution. It is highly eutrophic, and its sediment contains persistent pollutants, such as heavy metals. In anoxic sediments, sulphides represent an important binding phase for heavy metals. In this study, acid volatile sulphide (AVS) and simultaneously extracted metals (SEM) were analyzed in surface sediment extracted from Lake Albufera; organic matter and total metals were also analyzed. Twelve sites were sampled in each of three sampling campaigns conducted in March and September 2007 and September 2008. The results revealed elevated organic matter contents varying between 6.9 and 16.7%. The concentrations of AVS in the lake were high, ranging from 8.5 to 48.5 ¿mol/g; the lowest concentrations were found in the central sites. The AVS results displayed significant differences between the samples from the winter and summer of 2007 (p < 0.05) but not between the two summer samples. The results obtained for SEM varied from 1.4 to 4.8 ¿mol/g. The difference SEM-AVS was less than zero for all sampling locations and campaigns, indicating the existence of a sulphide pool able to bind metals. © 2012 Copyright Taylor and Francis Group, LLC.Hernández Crespo, C.; Martín Monerris, M.; Ferris Juan, M.; Oñate Ema, M. (2012). Measurement of Acid Volatile Sulphide and Simultaneously Extracted Metals in Sediment from Lake Albufera (Valencia, Spain). Soil and Sediment Contamination. 21(2):176-191. doi:10.1080/15320383.2012.649374S176191212Allen, H. E., Fu, G., & Deng, B. (1993). Analysis of acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) for the estimation of potential toxicity in aquatic sediments. Environmental Toxicology and Chemistry, 12(8), 1441-1453. doi:10.1002/etc.5620120812Besser, J. M., Brumbaugh, W. G., Ivey, C. D., Ingersoll, C. G., & Moran, P. W. (2007). Biological and Chemical Characterization of Metal Bioavailability in Sediments from Lake Roosevelt, Columbia River, Washington, USA. Archives of Environmental Contamination and Toxicology, 54(4), 557-570. doi:10.1007/s00244-007-9074-5Burton, G. A., Green, A., Baudo, R., Forbes, V., Nguyen, L. T. H., Janssen, C. R., … Dunning, J. (2007). CHARACTERIZING SEDIMENT ACID VOLATILE SULFIDE CONCENTRATIONS IN EUROPEAN STREAMS. Environmental Toxicology and Chemistry, 26(1), 1. doi:10.1897/05-708r.1Casado-Martínez, M. C., Buceta, J. L., Belzunce, M. J., & DelValls, T. A. (2006). Using sediment quality guidelines for dredged material management in commercial ports from Spain. Environment International, 32(3), 388-396. doi:10.1016/j.envint.2005.09.003Choi, J. H., Park, S. S., & Jaffé, P. R. (2006). Simulating the dynamics of sulfur species and zinc in wetland sediments. Ecological Modelling, 199(3), 315-323. doi:10.1016/j.ecolmodel.2006.05.009De Jonge, M., Blust, R., & Bervoets, L. (2010). The relation between Acid Volatile Sulfides (AVS) and metal accumulation in aquatic invertebrates: Implications of feeding behavior and ecology. Environmental Pollution, 158(5), 1381-1391. doi:10.1016/j.envpol.2010.01.001De Lange, H. J., Van Griethuysen, C., & Koelmans, A. A. (2008). Sampling method, storage and pretreatment of sediment affect AVS concentrations with consequences for bioassay responses. Environmental Pollution, 151(1), 243-251. doi:10.1016/j.envpol.2007.01.052Di Toro, D. M., Mahony, J. D., Hansen, D. J., Scott, K. J., Carlson, A. R., & Ankley, G. T. (1992). Acid volatile sulfide predicts the acute toxicity of cadmium and nickel in sediments. Environmental Science & Technology, 26(1), 96-101. doi:10.1021/es00025a009Du Laing, G., Rinklebe, J., Vandecasteele, B., Meers, E., & Tack, F. M. G. (2009). Trace metal behaviour in estuarine and riverine floodplain soils and sediments: A review. Science of The Total Environment, 407(13), 3972-3985. doi:10.1016/j.scitotenv.2008.07.025European Union. 2000. “Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy”. EU Water Framework Directive. OJ L 327 on 22 December 2000Fang, T., Li, X., & Zhang, G. (2005). Acid volatile sulfide and simultaneously extracted metals in the sediment cores of the Pearl River Estuary, South China. Ecotoxicology and Environmental Safety, 61(3), 420-431. doi:10.1016/j.ecoenv.2004.10.004Grabowski, L. A., Houpis, J. L. J., Woods, W. I., & Johnson, K. A. (2001). Seasonal bioavailability of sediment-associated heavy metals along the Mississippi river floodplain. Chemosphere, 45(4-5), 643-651. doi:10.1016/s0045-6535(01)00037-6Hernández-Crespo, C., Martín, M., Ferrís, M., Oñate, M. and Torán, M. 2010. “Spatial variation of Acid Volatile Sulfide (AVS) and Simultaneously Extracted Metals (SEM) in sediments from Beniarrés, Amadorio and Guadalest reservoirs (Alicante, Spain)”. Seville, Spain: 20th SETAC Europe Annual Meeting. Science and Technology for Environmental Protection.Jingchun, L., Chongling, Y., Spencer, K. L., Ruifeng, Z., & Haoliang, L. (2010). The distribution of acid-volatile sulfide and simultaneously extracted metals in sediments from a mangrove forest and adjacent mudflat in Zhangjiang Estuary, China. Marine Pollution Bulletin, 60(8), 1209-1216. doi:10.1016/j.marpolbul.2010.03.029Lee, J., Lee, B., Yoo, H., Koh, C., & Luoma, S. (2001). Influence of reactive sulfide (AVS) and supplementary food on Ag, Cd and Zn bioaccumulation in the marine polychaete Neanthes arenaceodentata. Marine Ecology Progress Series, 216, 129-140. doi:10.3354/meps216129Lee, J.-S., Lee, B.-G., Luoma, S. N., & Yoo, H. (2004). IMPORTANCE OF EQUILIBRATION TIME IN THE PARTITIONING AND TOXICITY OF ZINC IN SPIKED SEDIMENT BIOASSAYS. Environmental Toxicology and Chemistry, 23(1), 65. doi:10.1897/03-176Leonard, E. N., Mattson, V. R., Benoit, D. A., Hoke, R. A., & Ankley, G. T. (1993). Seasonal variation of acid volatile sulfide concentration in sediment cores from three northeastern Minnesota lakes. Hydrobiologia, 271(2), 87-95. doi:10.1007/bf00007545Longhi, D., Bartoli, M., & Viaroli, P. (2008). Decomposition of four macrophytes in wetland sediments: Organic matter and nutrient decay and associated benthic processes. Aquatic Botany, 89(3), 303-310. doi:10.1016/j.aquabot.2008.03.004Peng, S.-H., Wang, W.-X., Li, X., & Yen, Y.-F. (2004). Metal partitioning in river sediments measured by sequential extraction and biomimetic approaches. Chemosphere, 57(8), 839-851. doi:10.1016/j.chemosphere.2004.07.015Peris, E. 1999. “Caracterización de los materiales de fondo del lago de la Albufera evaluación del nivel de aterramiento y caracterización mineralógica de los materiales así como de la carga contaminante persistente residente en el lago”. Departamento de Ingeniería de la Construcción, Universidad Politécnica de Valencia.Public database of Condederación Hidrográfica del Júcar. 2011. Available at:http://www.chj.gob.es/Redesdecalidad/red_ica.aspxSpeelmans, M., Lock, K., Vanthuyne, D. R. J., Hendrickx, F., Du Laing, G., Tack, F. M. G., & Janssen, C. R. (2010). Hydrological regime and salinity alter the bioavailability of Cu and Zn in wetlands. Environmental Pollution, 158(5), 1870-1875. doi:10.1016/j.envpol.2009.10.040Técnica y and Proyectos S. A. (TYPSA). 2004. “Estudio para el desarrollo sostenible de l’ Albufera de Valencia”. Confederación Hidrográfica del Júcar, Ministerio de Medio Ambiente.UNE. 77322:2003—Calidad del suelo. Extracción de elementos traza solubles en agua regia (ISO 11466:1995) AENOR, Madrid, Spain. 2003U.S. EPA. 2005. “Procedures for the derivation of Equilibrium Partitioning Sediment Benchmarks (ESBs) for the protection of benthic organisms: Metal mixtures (Cadmium, Copper, Lead, Nickel, Silver and Zinc). EPA-600-R-02-011”. Washington, DC, USA: Office of Research and Development.Van Griethuysen, C., de Lange, H. J., van den Heuij, M., de Bies, S. C., Gillissen, F., & Koelmans, A. A. (2006). Temporal dynamics of AVS and SEM in sediment of shallow freshwater floodplain lakes. Applied Geochemistry, 21(4), 632-642. doi:10.1016/j.apgeochem.2005.12.010Zheng, L., Xu, X. Q., & Xie, P. (2004). Seasonal and Vertical Distributions of Acid Volatile Sulfide and Metal Bioavailability in a Shallow, Subtropical Lake in China. Bulletin of Environmental Contamination and Toxicology, 72(2), 326-334. doi:10.1007/s00128-003-9000-

Praderas de fanerógamas marinas en la bahía de Cádiz: conservación y gestión

Comunicación técnicaLa bahía de Cádiz es un humedal costero protegido por figuras de protección nacionales (Parque Natural) e internacionales (LIC, Convención Ramsar) dada su importancia ecológica. La biodiversidad biológica incluye numerosas especies de macroalgas, invertebrados, peces y aves. Un hecho de singular importancia, y poco conocido por las administraciones públicas, es que en este humedal conviven 3 de las 4 especies de fanerógamas marinas, o más estrictamente angiospermas marinas, de Europa. Las praderas de Cymodocea nodosa y Zostera noltii junto con escasos rodales de Zostera marina, proporcionan numerosos servicios ecológicos que están siendo estudiados por el grupo de Estructura y Dinámica de Ecosistemas Acuáticos de la Universidad de Cádiz. Desde hace 15 años hemos desarrollado proyectos tanto nacionales como internacionales en la bahía con el fin de poner en práctica bases ecológicas para la gestión de estas praderas como parte integrante del ecosistema. Estas herramientas abarcan desde un nivel ecofisiológico muy reduccionista (tasas fotosintéticas, incorporación de nutrientes), hasta un nivel más holista (mapas de cobertura, efecto a gran escala de variables ambientales, utilización de información para la estimación de la calidad ecológica de la masa de agua). Las actuaciones desarrolladas incluyen la consolidación de una red de voluntariado (FAMAR) para la recogida y análisis de la información. El trabajo que se presenta resume la información disponible, con series de datos recogidos y analizados durante la última década, para la gestión de las praderas y el estado de conservación de las mismas. Se incluyen además algunas perspectivas para la gestión.Proyecto ECOLAGUNES del programa europeo Interreg del espacio SUDOE (SOE1/P2/F153), proyecto IMACHYDRO, del Ministerio de Ciencia e Innovación (CTM2008-00012/MAR), proyectos de excelencia de la Junta de Andalucía FUNDIV (P07-RNM-02516), PAMBIO (P08-RNM-03783) y BAHÍA (P06-RNM0163713 página

The First Signal to Initiate Fruit Ripening is Generated in the Cuticle: An Hypothesis

The paradigm that has prevailed for a long time sustains that ethylene is the first signal that initiates fruit ripening. However, in this manuscript, we present the hypothesis that a signal generated from the cuticle induces the synthesis of ethylene, and therefore, it is the initial signal that triggers the fruit-ripening phenomena. Among the experimental evidence supporting the hypothesis, we can mention that cuticle components released during the plant pathogenic attack can induce the synthesis of ethylene in plants. Also, it has been found that in fungi, a cuticle component can activate a transcription factor by phosphorylation, which induces the transcription of a gene encoding a cutinase. Besides, studies with plant tissues experiencing a high rate of cell expansion have shown that there is a careful synchronization between the demand of cuticle components and biosynthesis, which suggests that the plant cell can sense the moment in which the fruit would stop growing by cell expansion, and initiate the ripening phenomena. In this chapter, experimental evidences supporting the physiological role of the fruit cuticle in the fruit ripening phenomena will be presented and reviewed with the goal to show a possible role of the fruit cuticle in the onset of fruit ripening

Preparation and characterization of a monocyclopentadienyl osmium−allenylcarbene complex

5 pages, 3 schemes, 1 table, 1 figure.-- Supporting Information Available: http: //pubs.acs.org.The dihydride−dihydrogen complex [OsH2(η5-C5H5)(η2-H2)(PiPr3)]BF4 (1) reacts with phenylacetylene to give the allenylcarbene derivative [Os(η5-C5H5){CPh(η2-CHCCHPh)}(PiPr3)]BF4 (2) via the π-phenylacetylene intermediate [Os(η5-C5H5)(η2-PhCCH)(PiPr3)]BF4 (3). The reactions of 2 with NaOMe and LiCCPh afford 3:1 mixtures of two hydride−osmaindene isomers of formula OsH(n5-C5H5)(C(C=CPh)=CHC6H4)(piPr3)(4 and 5) instead of the expected osmabenzyne complex.Financial support from the MEC of Spain (Projects CTQ2005-00656 and Consolider Ingenio 2010 CSD2007-00006)) and Diputación General de Aragón (E35) is acknowledged. Y.A.H. thanks the Spanish MEC for his grant.Peer reviewe

Reduction and C(sp2)-H bond activation of ketones promoted by a cyclopentadienyl-osmium-dihydride-dihydrogen complex

The dihydride-dihydrogen complex [OsH2(η5-C 5H5)(η2-H2)(PiPr 3)]BF4 (2) has been prepared by addition of HBF 4·OEt2 to OsH3H3(η 5-C5H5)(PiPr3) (1), and its reactions with benzylideneacetone, methyl vinyl ketone, acetophenone, and benzylideneacetophenone have been studied. The reaction with benzylideneacetone leads initially to [OsH2(η5-C5H 5){κ1-OC(CH3)CH=CHPh}-(P iPr3)]BF4 (3), which in dichloromethane is converted to the hydroxyallyl derivative [OsH-(η5-C 5H5){η3-CH2C(OH)CHCH 2Ph}(PiPr3)]BF4 (4). Complex 4 releases 4-phenylbutan-2-one, and the resulting metallic fragment activates a Cβ(sp2)-H bond of a new molecule of benzylideneacetone to give [OsH(η5-C5H 5){C(Ph)CHC(O)CH3}(PiPr3)]BF 4 (5), which affords Os(η5-C5H 5){C(Ph)CHC(O)CH3}(PiPr3) (6) by deprotonation with NaOCH3. The reaction of 2 with methyl vinyl ketone gives ethyl methyl ketone and [OsH(η5-C5H 5){CHCHC(O)-CH3}(PiPr3)]BF 4 (9). The latter can also be obtained from Os(η5- C5H5)Cl{η2-CH2=CHC(O)-CH 3(PiPr3) (7) via the intermediate [Os(η5-C5H5){CH2CHC(O)CH 3}(PiPr3)]BF4 (8). Treatment of 9 with NaOCH3 leads to an equilibrium mixture of Os(η5- C5H5){CHCHC(O)CH3}-(PiPr 3) (10) and the hydride-vinylidene OsH(η5-C 5H5){=C=CHC(O)CH3}(PiPr3) (11). The reaction of 2 with acetophenone gives 1-phenylethanol and the orthometalated derivative [OsH(η5-C5H5){C 6H4C(O)CH3}(PiPr3)] BF4 (13), which is deprotonated with NaOCH3 to give Os(η5-C5H5){C6H 4C(O)CH3 (14), while the reaction of 2 with benzylideneacetophenone leads to [OsH(η5-C5H 5){C(Ph)CHC(O)Ph}(PiPr3)]BF4 (15), which yields Os(η5-C5H5){C(Ph)CHC(O)Ph} (PiPr3) (16) by deprotonation. Complexes 3, 10, and 13 have been characterized by X-ray diffraction analysis. © 2005 American Chemical Society.Financial support from the MCYT of Spain (Proyect BQU2002-00606) is acknowledged. Y.A.H. thanks the Spanish MCYT for his grant.Peer Reviewe

One-pot dehydrogenative addition of isopropyl to alkynes promoted by osmium: Formation of γ-(η3-allyl)-α-alkenylphosphine derivatives starting from a dihydride−dihydrogen−triisopropylphosphine complex

10 pages, 1 table, 4 schemes, 1 figure.-- Supporting Information Available: http://pubs.acs.org.The dihydride−dihydrogen complex [OsH2(η5-C5H5)(η2-H2)(PiPr3)]BF4 (1) reacts in acetone with 1-phenyl-1-propyne and 2-butyne to give the γ-(η3-allyl)-α-alkenylphosphine derivatives [OsH(η5-C5H5){κ4-(P,C,C,C)-CH2C[CH2C(CH2)PiPr2]CHR}]BF4 (R = Ph (2), CH3 (3)), by means of one-pot tandem processes of four reactions. The stable intermediates have been isolated and characterized. In acetone, complex 1 dissociates H2 and coordinates the solvent to afford [OsH2(η5-C5H5)(κ1-OCMe2)(PiPr3)]BF4 (4), which reacts with a molecule of 1-phenyl-1-propyne or 2-butyne to form [OsH(η5-C5H5)(η3-CH2CHCHR)(PiPr3)]BF4 (R = Ph (5), CH3 (6)), containing the CHR group cisoid disposed to the phosphine and the R substituent anti to Cmeso. In dichloromethane, complexes 5 and 6 evolve to the thermodynamic isomers 7 and 8, containing the CHR group cisoid disposed to the hydride and the R substituent syn to Cmeso. The reactions of 5 and 6 with a second molecule of the respective alkyne lead to the corresponding Z-olefin and [Os(η5-C5H5){η2-(Z)-CH(CH3)CHR}{κ3-(P,C,C)-[CH2C(CH3)]PiPr2}]BF4 (R = Ph (9), CH3 (10)). The isopropenyl group of the phosphine of 9 and 10 undergoes coupling with a third alkyne molecule to give 2 and 3.Financial support from the MEC of Spain (Project CTQ2005-00656) and Diputación General de Aragón (E35) is acknowledged. Y.A.H. thanks the Spanish MEC for his grant.Peer reviewe

Chitosan-only nanoparticles against phytopathogenic fungi in the past decade (2013–2023)

Chitosan is a biocompatible, biodegradable, and antimicrobial polymer. Researchers have recently explored using chitosan nanoparticles to fight phytopathogenic fungi. This review aims to provide a comprehensive overview of studies conducted between 2013 and 2023 using the most popular databases for academic research on this topic. A systematic review was conducted using Software Rayyan to support the process. The search was conducted using the Web of Science, Scopus, and ScienceDirect databases. Out of the 752 records found from 2013–2023, only 83 articles were considered eligible for inclusion in the review after screening with inclusion and exclusion criteria. Most studies showed that chitosan nanoparticles are produced using sodium tripolyphosphate (TPP) through ionotropic gelation. However, using TPP has potential drawbacks and may have a synergistic effect with chitosan, which requires further investigation. TPP can affect the biological activity of the nanoparticle matrix. Furthermore, less than 10 out of the 83 articles reviewed in the time frame explored chitosan-only nanoparticles (nanochitosan) against phytopathogenic fungi. This shows the need for more research to determine the potential benefits of chitosan-only nanoparticles in control phytopathogenic fungi

La cadena productiva de guanábana: una opción para el desarrollo económico en Compostela, Nayarit

Objective: Characterize Compostela’s Soursop Production Chain, describe the risks that represent areas of opportunity, and propose an Intervention Order that settled the critical control points that must be implemented to promote Mexican soursop on international markets. Methodology: The approach to calculate the optimal intervention order for the Soursop Production Chain was designed based on direct and indirect information sources and consisted of five phases. Results: Compostela’s SPC is made up of three primary links: production, processing, and marketing, involving actors for each specific task. High-risk weak points and Critical Control Points were identified. Implementing these Critical Control Points would significantly improve the Soursop Production Chain’s revenue. An intervention order designed to configure the Soursop Production Chain as a successful regional development option was built based on the relevance analysis of each Critical Control Point. Limitations: Available information regarding soursop production and post-harvest is relatively scarce. Gathering this type of information represents an area of opportunity that requires consulting the actors that make up the chain. Conclusions: Compostela’s soursop presence in international high value markets is limited by risks in the Soursop Production Chain. This fruit’s perishable nature stands out as the main risk, which is aggravated by phytosanitary risks, poor interlink coordination, outdated handling techniques, and poor storage and transportation infrastructure. A conservative estimate suggests that by implementing this Intervention Order, Soursop Production Chains’s profits would increase at least 175% in a short to medium term.Objetivo: caracterizar la cadena productiva de guanábana en el municipio de Compostela, Nayarit, México, y describir las áreas de oportunidad y sus riesgos para proponer un orden de intervención de esa cadena productiva que establezca los puntos críticos de control que deben implementarse para impulsar la comercialización de guanábana mexicana en el mercado internacional. Metodología: partiendo de fuentes de información directas e indirectas, se construyó una base metodológica que consta de cinco fases diseñadas para calcular el OI óptimo. Resultados: La Cadena Productiva de Guanábana de Compostela se compone de tres eslabones primarios: producción, procesamiento y comercialización, compuestos por actores que cumplen labores específicas. Se identificaron puntos débiles de alto riesgo, así como los Puntos de Control Críticos en la Cadena Productiva de la Guanábana. En base al análisis de relevancia de cada Punto Crítico de Control se construyó un Orden de Intervención diseñado para configurar a la Cadena Productiva de la Guanábana como una opción de desarrollo regional exitosa. Limitaciones: La información disponible del sistema productivo y poscosecha de la guanábana es relativamente escaza. Generar este tipo de información representa un área de oportunidad que requiere el acercamiento con los actores que conforman la cadena. Conclusiones: La presencia de guanábana de Compostela en mercados internacionales de alto valor se ve limitada por riesgos presentes en su cadena productiva. La naturaleza perecedera del fruto destaca como el riesgo principal, y se agrava por riesgos fitosanitarios, mala coordinación entre eslabones, técnicas de manejo desactualizadas e infraestructura de almacenamiento y transporte deficiente. Se estima que implementar el Orden de Intervención incrementaría las ganancias de la Cadena Productiva de la Guanábana al menos 175% en un corto a mediano plazo