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En el marco del ciclo “Pioneras: las cientificas del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (Buenos Aires, Argentina)” rendimos homenaje a mujeres que se han destacado en diversas actividades cientificas en la Institucion. En el ano 2019 distinguimos al primer grupo de mujeres cientificas argentinas que participaron de una campana de investigacion en la Antartida. Las cuatro biologas que trabajaron en la Base Melchior durante el verano 1968-1969 fueron Irene Maria Bernasconi, Maria Adela Caria, Elena Dolores Martinez Fontes y Carmen Pujals. Presentamos informacion sobre su viaje a bordo del buque carguero ARA Bahia Aguirre, la expedicion al continente blanco y una breve biografia de cada una de ellas.

The objective of this study was to evaluate the accumulation and uptake of Cr, Zn, Cu, Ni and Pb in Sagittaria montevidensis growing in highly contaminated riparian soils of Matanza Riachuelo Basin (MRB). It is a native and very abundant riparian plant exposed to heavy metal contamination. Samples of S. montevidensis, rhizosphere riparian soil and water were collected at three sites in the lower MR basin. The accumulation and the level of translocation of Cr, Zn, Cu, Ni and Pb in this species were determined. The soils were found to be the main reservoirs of metals (2225 mg Cr kg−1 d.w., 367 mg Cu kg−1 d.w., 61 mg Ni kg−1 d.w., 239 mg Pb kg−1 d.w., and 1495 mg Zn kg−1 d.w.). All studied metals were uptaken, but Zn and Cu were the most accumulated metals (426 ± 28 mg kg−1 d.w. and 129 ± 28 mg kg−1 d.w., respectively). S. montevidensis was an accumulator species for Cu and Ni (Translocation Factor (TF) > 1) and it showed an exclusionary behavior (TF < 1) for Cr, Pb, and Zn. Cu was mostly accumulated in the aerial biomass. The rest of the metals analyzed were mainly accumulated in the roots. The analyzed plant specimens did not show signs of stress, having completed their phenological states. This native species shows high tolerance of metals. Then the preservation and revegetation of this species in the riparian areas constitute a sustainable alternative for ecological restoration. Fil: Gomez, Barbara Marion. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina Fil: Reale, Marisol. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina Fil: El Kassisse, Yanina. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina Fil: Mujica, Carolina. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina Fil: Gómez, Carlos. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina Fil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Rodríguez Salemi, Valeria. Provincia de Mendoza. Ministerio de Infraestructura y Vivienda. Secretaria de Obras Publicas. Instituto Nacional del Agua; Argentina

The process of vermicomposting organic waste generates leachate, a by-product that can be used for irrigation. In the present research, different dilutions of vermicomposting leachate were used for the irrigation of Austroeupatorium inulifolium and Erythrina crista-galli seedlings, two ornamental, woody species native to South America. Leachate dilutions were 5% and 10% (L5% and L10%, E. crista-galli) or 10% (L10%, A. inulifolium). In addition, two commercial liquid fertilizers were tested in E. crista-galli bioassay. In both assays the plants were irrigated with deionized water for a control. The pH, electrical conductivity (EC), and organic matter content (OM%) of substrate seedlings were measured before and after irrigation with the different solutions. The growth of plants was assessed by means of height, stem diameter, aerial tissues, and root and total fresh weights. The phytotoxicity of the leachate and its dilutions were evaluated by means of the Allium cepa test. In both assays the plants were irrigated with deionized water for a control. The growth of plants of both species does not show statistically significant differences with respect to the control, but total biomass of A. inulifolium was higher in L10% treatment. On the other hand, there were no observable symptoms of phytotoxicity in any of the plants, although the test of A. cepa showed a lower germination percentage and a higher percentage of micronuclei in the dilutions of leachate.

Wetlands usually provide a natural mechanism that diminishes the transport of toxic compounds to other compartments of the ecosystem by immobilization and accumulation in belowground tissues and/or soil. This study was conducted to assess the ability of Schoenoplectus californicus growing in natural marsh sediments, with zinc and lead addition, to tolerate and accumulate these metals, taking account of the metal distribution in the sediment fractions. The Zn and Pb were mainly found in available (exchangeable) and potentially available (bound to organic matter) forms, respectively. The absorption of Zn and Pb by plants increased in sediments with added metals. Both metals were largely retained in roots (translocation factor

La vegetación ribereña desempeña un rol importante en el control de fuentes no puntuales de contaminación y contribuye a la consiguiente mejora de la calidad del agua de ríos y arroyos. El río Matanza-Riachuelo ha sido clasificado como uno de los más contaminados del mundo, registrándose concentraciones elevadas de metales y otros contaminantes en la columna de agua y en los sedimentos de sus riberas. El objetivo de este trabajo consistió en realizar una caracterización física, química y florística y poner a prueba una intervención para la rehabilitación ecológica en un área piloto de la ribera del río Matanza-Riachuelo. Se determinaron cromo, cadmio, níquel, zinc, cobre y plomo en muestras de sedimentos ribereños y en muestras de las herbáceas Sagittaria montevidensis y Tradescantia fluminensis. Los suelos presentaron muy alto grado de contaminación, fundamentalmente debido a los elevados valores de cromo, cobre y zinc. Ambas herbáceas toleraron la variación del nivel del agua y acumularon metales, principalmente en sus estructuras subterráneas. Estas características indicaron que S. montevidensis y T. fluminensis podían ser utilizadas en intervenciones para la rehabilitación de riberas. La rehabilitación consistió en la plantación directa de 45 ejemplares de árboles y arbustos nativos con tolerancia al estrés ambiental (Erythrina crista-galli, Senna corymbosa, Solanum granulosum-leprosum, Allophylus edulis, Syagrus romanzoffiana, Salix humboldtiana, Lantana camara, Cestrum parqui y Sesbania punicea); en la línea de costa se instalaron 66 biorrollos para la implantación de las helófitas nativas: Hydrocotyle bonariensis, Tripogandra diuretica, T. fluminensis, Schoenoplectus californicus, S. montevidensis y Echinodorus grandiflorus. El monitoreo posterior demostró que los árboles y arbustos toleraron tanto los niveles de contaminación de los suelos como el prolongado periodo de inundación. La implantación de macrófitas S. californicus, S. montevidensis y E. grandiflorus mediante la técnica de biorrollos fue una alternativa eficaz pero los helófitos rastreros: H. bonariensis, T. fluminensis y T. diuretica resultaron afectados fundamentalmente por el depósito de basura flotante., Riparian vegetation plays an important role in the control of non-point sources of pollution and the improvement of the water quality of rivers and streams. The Matanza-Riachuelo River has been classified as one of the most polluted in the world, according to high levels of metals and other pollutants in the water column and in the sediments of its banks. The objective of this work was to carry out a physical, chemical and floristic characterization and to test an intervention for ecological rehabilitation in a riparian pilot area of the Matanza-Riachuelo River. Chromium, cadmium, nickel, zinc, copper and lead were determined in sediment and samples of the herbaceous: Sagittaria montevidensis and Tradescantia fluminensis. Both herbaceous plants tolerate the variation of water level and accumulate metals, mainly in their underground structures. These characteristics indicate that S. montevidensis and T. fluminensis could be used in the rehabilitation of banks. The rehabilitation consisted in the direct planting of 45 specimens of native trees and shrubs tolerant to environmental stress (Erythrina crista-galli, Senna corymbosa, Solanum granulosum-leprosum, Allophylus edulis, Syagrus romanzoffiana, Salix humboldtiana, Lantana camara, Cestrum parqui y Sesbania punicea), in the coastal line were installed 66 prevegetated rolls for the implantation of the native helophytes: Hydrocotyle bonariensis, Tripogandra diuretica, T. fluminensis, Schoenoplectus californicus, S. montevidensis y Echinodorus grandiflorus. The subsequent monitoring showed that the trees and shrubs tolerated both the levels of soil contamination and the prolonged period of flooding. The implantation of macrophytes (S. californicus, S. montevidensis y E. grandiflorus) by the technique of prevegetated rolls proved to be a good alternative, but the helophytes: H. bonariensis, T. fluminensis y T. diuretica were affected mainly by depositing floating debris., Instituto de Limnología "Dr. Raúl A. Ringuelet"

Decomposition of plant debris is an important process in determining the structure and function of aquatic ecosystems. The aims were to find a mathematic model fitting the decomposition process of Schoenoplectus californicus shoots containing different Zn concentrations; compare the decomposition rates; and assess metal accumulation/mobilization during decomposition. A litterbag technique was applied with shoots containing three levels of Zn: collected from an unpolluted river (RIV) and from experimental populations at low (LoZn) and high (HiZn) Zn supply. The double exponential model explained S. californicus shoot decomposition, at first, higher initial proportion of refractory fraction in RIV detritus determined a lower decay rate and until 68 days, RIV and LoZn detritus behaved like a source of metal, releasing soluble/weakly bound zinc into the water; after 68 days, they became like a sink. However, HiZn detritus showed rapid release into the water during the first 8 days, changing to the sink condition up to 68 days, and then returning to the source condition up to 369 days. The knowledge of the role of detritus (sink/source) will allow defining a correct management of the vegetation used for zinc removal and providing a valuable tool for environmental remediation and rehabilitation planning. Fil: Arreghini, Silvana. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Química Analítica; Argentina Fil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Serafini, Roberto José María. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Química Analítica; Argentina Fil: Fabrizio de Iorio, Alicia Rosa. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Química Analítica; Argentina

Matanza-Riachuelo river is the most polluted river in Argentina and one of the most pollute drivers in the world. Among the pollutants in the riverbank sediments, metals can be found in toxic concentrations to biota. During 2015, a pilot-scale rehabilitation was carried out in a selected section of the riverbank located in the lower basin of the river, which consisted of the reintroduction of several native plant species, including Erythrina crista-galli and Senna corymbosa (Fabaceae). In order to evaluate the tolerance of these species to polluted sediments and quantify the bioaccumulation of Cr, Cu, and Pb in aerial tissues and roots, a 153-day trial was carried out using seedlings of both species cultivated from seeds. It was found that both species showed good growth in riverbank sediments polluted with metals. None of the species has accumulated significant amounts of Cr, Cu, or Pb, and the translocation of Pb from the roots to the aerial tissues has been observed only in the case of E. crista-galli after 5 months of planting. However, the concentration of this metal in the aerial biomass was low. Individuals of both species planted in the riverbank showed tolerance not only to the contaminants present in the sediments but also to the environmental stress of the riverbank.

This study assessed the contamination by heavy metals (Cr, Cu, Pb, Zn), and nutrients (N, P) in soils and native plants, and the effect of the concentration of those elements with the density of arbuscular-mycorrhizal (AM) spores in soil and colonization in roots from the riverside of the Matanza-Riachuelo River Basin (MRRB). The concentration of metals and nutrients in soils and plants (Eleocharis montana, Cyperus eragrostis, Hydrocotyle bonariensis) increased from the upper sites (8 km from headwaters) to the lower sites (6 km from the mouth of the Riachuelo River) of the basin. AM-colonization on the roots of H. bonariensis and spore density in soil decreased as the concentrations of metals in soil and plant tissues increased from the upper to lower sites of the basin within a consistent gradient of contamination associated with land use, soil disturbance, population, and chemicals discharged into the streams and rivers along the MRRB. The general trends for all metals in plant tissue were to have highest concentrations in roots, then in rhizomes and lowest in aerial biomass. The translocation (TF) and bioconcentration (BCF) factors decreased in plants which grow from the upper sites to the lower sites of the basin. The plants tolerated a wide range in type and quantity of contamination along the basin by concentrating more metals and nutrients in roots than in aboveground tissue. The AM spore density in soil and colonization in roots of H. bonariensis decreased with the increase of the degree of contamination (Dc) in soil.

Los ambientes acuaticos de la llanura pampeana (Argentina) estan sometidos a presiones humanas crecientes, tales como el vertido de aguas residuales domesticas e industriales. Se llevaron a cabo ocho campanas de muestreo en el periodo 2010-2013 tomandose muestras de agua superficial en varios sitios de los arroyos La Choza y Durazno (cuenca alta del Rio Reconquista, Buenos Aires) y en canales que reciben efluentes agroindustriales (industrias avicola y feedlot porcino). Se adaptaron y aplicaron dos nuevos indices: Indice de Calidad de Aguas Pampeanas (ICAP) e Indice de Calidad de Riberas Pampeanas (ICRP). Las variables utilizadas para el calculo del ICAP fueron solidos suspendidos totales (SST), nitrogeno amoniacal (N-NH 4 + ), fosforo total (Pt), DBO 5 y oxigeno disuelto (OD). Ademas se calculo el Indice de Calidad de Aguas (ICA). Para el desarrollo del ICRP se utilizo como base el Indice de Calidad del Bosque de Ribera (QBR). El vertido de aguas residuales de la industria avicola contribuyo al incremento de las concentraciones de SST, N-NH 4 + , Pt y DBO 5 . Los valores medios de ICA e ICAP fueron bajos y similares, aunque ICAP resulto mas efectivo en la diferenciacion de casos con calidades de agua extremas. Los principales factores que redujeron el valor del ICRP fueron la ausencia o escasa abundancia de hierbas palustres, la presencia de especies vegetales exoticas e invasoras y la existencia de estructuras transversales al cauce. Los resultados sugieren que el uso conjunto de los indices desarrollados consiste una alternativa util en la evaluacion ambiental de arroyos de la llanura pampeana.

The discharge of sewage effluents into low-order streams has negative effects on water quality. Macrophytes can be efficient in the treatment of this wastewater due to the removal of the main pollutants. The genotoxicity of sewage-polluted water discharging into La Choza stream was evaluated by testing with Allium cepa. Also, a phytoremediation assay with continuous recirculation of the residual water was conducted for 12 days. Three treatments were carried out. One treatment (Hr) was performed with a macrophyte (Hydrocotyle ranunculoides), and two treatments were conducted without macrophytes: with lighting (Ai) and without lighting (Ao). The wastewater was toxic according to all the evaluated indexes (mitotic index, frequency of chromosomal aberrations and micronucleus). High concentrations of ammonium, dissolved inorganic nitrogen (DIN), total (TP) and soluble reactive phosphorous (SRP) and indicators of faecal contamination were determined in the wastewater. The ammonium, DIN, SRP and TP loads at the end of the assay were significantly lower in the treatments with light (Hr and Ai). So, the nutrient removal was due to their absorption and adsorption by the periphyton and H. ranunculoides. Our results lead us to recommend the maintenance and planting of macrophytes in lowland streams subject to sewage pollution. Fil: Basílico, Gabriel Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina Fil: Magdaleno, Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Paz, Marta Laura. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Moretton, Juan Agustin. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Faggi, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina Fil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina

Industrial production of poultry meat is associated with indirect environmental impacts such as contributing to climate change and deforestation and otherdirect impacts such as the deterioration of the quality ofsurface waters. Poultry industry effluents are rich inorganic matter, nitrogen, and phosphorus; nutrients canbe removed from wastewater through the use of macrophytes and periphyton. An essay in mesocosms withpoultry industry wastewater recirculation was developed in the presence and absence of a native macrophyteSpirodela intermediaand periphyton from a lowlandstream (La Choza stream, Buenos Aires) where theeffluent is poured. The diffusion of O2,increasedbywater recirculation, had the effect of increasing theconcentration of dissolved oxygen in wastewater. Thepresence ofS. intermediaand algae periphyton significantly contributed to the removal rates (%) of solids(69.7 ± 3.9), ammonium nitrogen (84.0 ± 3.4), and totalphosphorus (38.1 ± 1.8) from residual water and favorednitrification. The dominance of Bacillariophyceae onother groups of algae of periphyton and the low representation of Euglenophyceae indicated an advancedstage of the effluent treatment process at the end of theassay. Fil: Basílico, Gabriel Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina Fil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina Fil: Magdaleno, Anahí. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina Fil: Faggi, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Flores; Argentina

The rehabilitation of degraded riparian environments seeks to recreate natural ecosystems by the reintroduction of native plant species, among other actions. This reintroduction could be conducted from seed, saplings, and planted rolls and blankets. The advantages of the planted rolls and blankets are the ease of field installation and a rapid establishment of vegetation due to a better protection of the roots. In addition, rolls and mats reduce erosion, stabilize slopes, and retain sediments. The creation of wetlands in the coastal zone and the use of artificial vegetated floating islands can contribute to improving water quality. The establishment of buffer areas adjacent to the shore zone acts as a biological filter retaining diffuse pollution associated with surface runoff. In this chapter are described some low-tech alternatives and strategies that can be used in the rehabilitation of riparian zones, including a case study in the Matanza-Riachuelo River (Argentina), one of the most polluted in the world.

There are a few studies about full scale and on-site treatments using macrophytes. In this contribution we compare the phytoremediation role of floating, submersed, and emergent macrophytes grown in natural and artificial wetlands. Metal uptake capacity of aquatic plants is low and this exclusion strategy seems to be more widespread among aquatic plants. Bioconcentration factors and translocation are lower than those calculated in bioassays conducted under laboratory conditions. There are not hyperaccumulators among the studied plants. However, regarding the capacity of accumulation of metals in the standing crop, the floating plants are most effective for phytoextraction, followed by submersed species and then emergent species. The emergent plants are more effective for phytostabilization. The metals released during the decomposition could be further retained by the new binding sites generated in bottom sediment. Use of native species in remediation projects, not always considered in scientific or technical papers is essential to preserve biological diversity and, requires more detailed studies for each natural ecosystem.