RECONSTRUCTING THE ECOLOGICAL HISTORY AND PAST ENVIRONMENTS OF NATIVE OLYMPIA OYSTERS TO INFORM THEIR CONSERVATION AND RESTORATION IN THE SALISH SEA

Historical baselines inform restoration efforts, allowing us to interpret long-term changes in marine ecosystems prior to anthropogenic activities. In Washington State, restoration of native oysters (Ostrea lurida) is limited by shifting baselines and the lack of information on Olympia oyster populations before they collapsed in the late 1800s. Our project seeks to answer three main questions: (i) What was the water temperature and salinity in environments where historical native oysters thrived in the past? To answer this question we will use oxygen isotopes, Ba/Ca ratios and radiocarbon dating. (ii) How does the abundance of trace metals found in past Olympia oysters compare to the abundance of trace metals found in this species today? To answer this question, we will carry out mass spectrometry (ICP-MS) analyses to measure trace metal content in shells. (iii) Can we reconstruct past biotic interactions, such as parasitism and predation, from historical oyster shells and compare the prevalence of these interactions with what we see today? To answer this question, we will observe and record traces of past biotic interaction such as those left by shell-boring polychaete worms, and traces of predation by drilling gastropods. Assessing the past prevalence of these interactions together with radiocarbon dating of shells will allow us to generate a timeline for the abundance of pests and predators that may be threatening the success of contemporary restoration projects. Historical and fossil shells are proven to be informative, quantitative tools to reconstruct past environments and biotic interactions. The insights gained from the integration of these past baselines with modern environments will help advise the planning and management of conservation and restoration efforts for Olympia oysters in the Salish Sea

PREVALENCE, DISTRIBUTION, AND CONTROL OF SHELL-BORING POLYCHAETES ON OYSTER FARMS FROM CALIFORNIA TO ALASKA

Marine polychaetes in the genus Polydora (and other related genera) burrow into the shells of commercially important bivalves, creating unsightly blisters and burrows. Because they are unappealing to consumers, these blisters are an economic burden on producers whose stock goes to the half-shell market. The US west coast is the leading producer of aquaculture oysters in the country, making it important to understand the prevalence of these pests in Pacific oysters. We obtained over 3,000 oysters from 35 farms in four states (CA, OR, WA and AK) to determine infestation prevalence. Prevalence per state ranged from 13 to 37%. Polychaetes were extracted from infested shells for molecular analyses. We used mitochondrial (CO1) and nuclear (18S) genes for species-level identification, and these genetic markers confirmed the presence of P. websteri and P. hoplura, as well as other polychaete species. Given the difficulties faced by growers in controlling this pest, we consulted shellfish farmers from Washington State to create treatments that are both effective and easy to apply on farms. We tested three treatments in experiments carried out with Pacific oysters infested with shell-boring polychaetes collected from Washington State. Our experimental design consisted of three stages: (1) the main experiment to test treatments, (2) a growth assessment, (3) and respirometry trials. We subjected 675 oysters to three treatments: ‘Dry’, ‘Fresh-Dry’, ‘Refrigeration’ and a Control. The ‘Dry’ treatment was 100% effective at killing worms and the other two treatments were nearly as effective. The growth assessment indicated that none of the treatments negatively affected oyster growth, and the respirometry trials showed no differences in oxygen consumption between treatments. Findings from this study will allow us to advise the US west coast shellfish industry on the progress of the spread of shell-boring polychaetes and strategies for reducing the economic impacts of these globally-distributed pests

Importancia del bosque nativo en la dinámica del agua : influencia de las especies Prosopis Flexuosa, Bulnesia Retama y suelo desnudo sobre la infiltración en la zona sur de la cuenca de Bermejo San Juan

Se estudió el efecto de las especies Prosopis Flexuosa y Bulnesia Retama sobre la tasa de infiltración en el bosque nativo presente en la zona sur de la cuenca de Bermejo (San Juan, Argentina). Para la toma de datos de campo, se definieron las unidades homogéneas sobre la base de mapeo participativo y procesamiento de un modelo digital de elevación. Se identificaron las comunidades vegetales y a través del método de línea intersección se registró cobertura de las especies seleccionadas y de suelo desnudo. Además se cuantifico la infiltración debajo de la canopia con un infiltrómero de anillo simple de 21 cm de diámetro y con carga variable. Se obtuvieron las microcuencas correspondientes a una escala de 50000 celdas y la red hídrica. La cobertura promedio de Prosopis Flexuosa alcanzó el valor de 44 % mientras que la de Bulnesia Retama fue de 48 %. Respecto de la velocidad de infiltración, ésta fue mayor debajo dela canopia de las especies en comparación con suelo desnudo. El análisis de la capacidad de infiltración mostró que la misma se alcanzó con 450 milímetros de agua para ambas especies estudiadas y 300 milímetros para suelo desnudo Finalmente el presente estudio pretende aportar información de base para el manejo integrado de los recursos naturales en general y en particular del recurso hídrico en las zonas áridas.Was studied the effect of the species Prosopis flexuosa and Bulnesia retama on the rate of infiltration in the native forest in the southern zone of the Bermejo basin (San Juan, Argentina). For the field data collection, homogeneous units were defined based on participatory mapping and processing of a digital elevation model. Was identified plant communities and through the method intersection line was recorded coverage of species selected and bare soil. In addition, the infiltration under canopy was quantified with a single ring infiltramer of 21 cm diameter and with variable load. were obtained the corresponding micro-basins on a scale of 50000 cells and the water network. The average coverage of Prosopis flexuosa reached 44% while that of Bulnesia retama was 48%. Regarding infiltration speed, this was higher under canopy species compared to bare soil. The analysis of infiltration capacity showed that the same was achieved with 450 millimeters of water for both species studied and 300 millimeters for bare soil. Finally The present study aims to provide basic information for integrated management of natural resources in general and in particular of water resources in arid zones.Fil: Tapia, Raúl. Consejo Nacional de Investigaciones Científicas y TécnicasFil: Carmona, Julieta. Consejo Nacional de Investigaciones Científicas y TécnicasFil: Heredia, Belén.Fil: Martinelli, Mariana. Instituto Nacional de Tecnología Agropecuaria (Argentina). Centro Regional Mendoza-San Juan

Use of indicators as a tool to measure sustainability in agroecosystems of arid land, San Juan, Argentina

The main objective of this study was to determine the sustainability status of three agroecosystems in arid areas, and to identify the critical aspects that limit it, through the use of economic, ecological and socio-cultural indicators. Three agroecosystems (AE) were selected from the Department of 25 de Mayo, San Juan. Its main economic activity is goat farming and, to a lesser extent, cultivation of orchards, as well as subsistence economic activities. To determine the state of sustainability, the indicators were selected and subse-quently standardized and weighted according to their relative importance with respect to sustainability. The results indicated that none of the dryland AE achieves sustainability simultaneously in its three dimensions. The systemic analysis through indicators showed that the critical variables are food self-sufficiency, water access, livestock survival, and technical assistance, among others. The methodology used is simple, allowing to detect the sustainability status of the three EAs, and to identify the critical variables that jeopardize the permanence of the AE over time. Highlights Agroecosystems in arid zones do not achieve sustainability in all three dimensions simultaneously. The farm area of "‹"‹the agroecosystems was determined through participatory mapping. According to the sustainability analysis, the critical variables that stood out were food self-sufficiency, access to quality water, the survival of livestock and the satisfaction of basic needs. The use of indicators to measure sustainability is easy to use and low-cost tools.The main objective of this study was to determine the sustainability status of three agroecosystems in arid areas, and to identify the critical aspects that limit it, through the use of economic, ecological and socio-cultural indicators. Three agroecosystems (AE) were selected from the Department of 25 de Mayo, San Juan. Its main economic activity is goat farming and, to a lesser extent, cultivation of orchards, as well as subsistence economic activities. To determine the state of sustainability, the indicators were selected and subse-quently standardized and weighted according to their relative importance with respect to sustainability. The results indicated that none of the dryland AE achieves sustainability simultaneously in its three dimensions. The systemic analysis through indicators showed that the critical variables are food self-sufficiency, water access, livestock survival, and technical assistance, among others. The methodology used is simple, allowing to detect the sustainability status of the three EAs, and to identify the critical variables that jeopardize the permanence of the AE over time. Highlights Agroecosystems in arid zones do not achieve sustainability in all three dimensions simultaneously. The farm area of "‹"‹the agroecosystems was determined through participatory mapping. According to the sustainability analysis, the critical variables that stood out were food self-sufficiency, access to quality water, the survival of livestock and the satisfaction of basic needs. The use of indicators to measure sustainability is easy to use and low-cost tools

Use of indicators as a tool to measure sustainability in agroecosystems of arid land, San Juan, Argentina = Uso de indicadores como herramienta para medir la sustentabilidad en agroecosistemas de tierras áridas, San Juan, Argentina

The main objective of this study was to determine the sustainability status of three agroecosystems in arid areas, and to identify the critical aspects that limit it, through the use of economic, ecological and socio-cultural indicators. Three agroecosystems (AE) were selected from the Department of 25 de Mayo, San Juan. Its main economic activity is goat farming and, to a lesser extent, cultivation of orchards, as well as subsistence economic activities. To determine the state of sustainability, the indicators were selected and subse-quently standardized and weighted according to their relative importance with respect to sustainability. The results indicated that none of the dryland AE achieves sustainability simultaneously in its three dimensions. The systemic analysis through indicators showed that the critical variables are food self-sufficiency, water access, livestock survival, and technical assistance, among others. The methodology used is simple, allowing to detect the sustainability status of the three EAs, and to identify the critical variables that jeopardize the permanence of the AE over time.El objetivo principal de este estudio fue determinar el estado de sustentabilidad de tres agroecosistemas en tierras áridas, e identificar los aspectos críticos que la limitan, mediante el uso de indicadores económicos, ecológicos y socioculturales. Se seleccionaron tres agroecosistemas (AE) del departamento de 25 de Mayo, San Juan. Su principal actividad productiva es la producción caprina y en menor medida la producción de huerta, ambas orientadas a una economía de subsistencia. Los indicadores seleccionados se estandarizaron y ponderaron de acuerdo a su importancia relativa con respecto a la sustentabilidad. Los resultados indican que ninguno de los AE alcanza la sustentabilidad en sus tres dimensiones simultáneamente. El análisis sistémico a través de indicadores mostró que las variables críticas son la autosuficiencia alimentaria, el acceso al recurso hídrico, la supervivencia del ganado y la asistencia técnica, entre otras. La metodología utilizada fue fácil de usar, permitió detectar el estado de la sustentabi-lidad de los tres AE e identificar las variables críticas que ponen en peligro la perma-nencia de los AE en el tiempo.EEA San JuanFil: Carmona Crocco, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnologías Agropecuarias (INTA). Estación Experimental Agropecuaria San Juan; ArgentinaFil: Greco, Silvina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Tapia, Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnologías Agropecuarias (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ingenieria; ArgentinaFil: Martinelli, Mariana. Instituto Nacional de Tecnologías Agropecuarias (INTA). Estación Experimental Agropecuaria San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencia Exactas, Físicas y Naturales; Argentin

Remote sensing techniques to identify and characterize forage communities in a livestock system in the hyper-arid desert of San Juan (Argentina)

Introducción y Objetivos: Los pastizales naturales de zonas áridas cubren el 40% de la superficie terrestre y son una valiosa fuente de forraje para el ganado. El manejo inapropiado y las altas cargas ganaderas figuran entre factores responsables de su degradación. En ese sentido una rápida evaluación es fundamental para corregir su uso y promover la conservación. El objetivo del estudio fue identificar y caracterizar, mediante el procesamiento de imágenes satelitales y trabajo de campo, comunidades forrajeras en un sistema ganadero del secano de San Juan. M&M: A partir de una imagen Landsat 8 OLI se generaron variables indicadoras de suelo y vegetación. Posteriormente se realizó la clasificación no supervisada kmeans. En campo se registró, a partir de transectas lineales, cobertura vegetal, de mantillo y porcentaje de suelo desnudo. Finalmente se estimó la receptividad ganadera de las comunidades forrajeras. Resultados: Se identificaron 3 clases de coberturas: cobertura superior al 50%; superior al 20 % e inferior al 50 % e inferior al 20 % y dos comunidades forrajeras, Lamaral y Zampal. En Lamaral, Prosopis alpataco var. lamaro obtuvo un 35% cobertura y una receptividad de 2.21 hectárea/Equivalente cabra. En Zampal, se registró un 42 % de cobertura de Atriplex undulata y la receptividad fue de1.80 hectárea/Equivalente cabra. Conclusiones: El procesamiento digital realizado fue adecuado para el objetivo del estudio y permitió reconocer, caracterizar y mapear dos comunidades forrajeras. La riqueza de especies fue baja existiendo un predominio de plantas arbustivas y leñosas, esto limita la ganadería de la zona.Background and aims: The natural grasslands of arid zones cover 40% of the earth’s surface and are a valuable source of forage for livestock. Inappropriate management and high livestock loads are among the factors responsible for their degradation. In this sense, a fast evaluation is essential to correct its use and promote conservation. The objective of the study was to identify and characterize, through satellite image processing and fieldwork, forage plant communities in a rainfed livestock system of San Juan.M&M: Indicator variables of soil and vegetation were generated from a Landsat 8 OLI image. Subsequently, unsupervised kmeans classification was performed. On field, plant cover, mulch and percentage of bare soil were registered from linear transects. Finally, the livestock receptivity of the plant communities was estimated.Results: 3 types of coverage were identified: coverage higher than 50%; higher than 20% and less than 50% and less than 20%. Also, two forage communities were identified, Lamaral and Zampal. In Lamaral, Prosopis alpataco var. lamaro obtained a coverage of 48%, a receptivity of 2.21 hectare/goat equivalent. In Zampal, a 35% coverage of Atriplex undulata was registered and the receptivity was 1.80 hectare/goat equivalent.Conclusions: The digital processing carried out was adequate for the purpose of the study and allowed recognizing, characterizing and mapping two forage communities. The richness of the species was low, with a predominance of shrubs and woody plants, limiting livestock in the area.EEA San JuanFil: Tapia, Raúl Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina.Fil: Tapia, Raúl Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carmona Crocco, Julieta. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina.Fil: Carmona Crocco, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Martinelli, Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina.Fil: Martinelli, Mariana. Universidad Nacional de San Juan; Argentina

Regional-scale compositional and size fidelity of rocky interdidal comminities from the patagonian atlantic coast

Fil: Archuby, Fernando M.. Instituto de Investigación en Paleobiología y Geología. Universidad Nacional de Río Negro. General Roca; ArgentinaFil: Adami, Mariana Laura. División Zoología Invertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Martinelli, Julieta C.. Department of Biological Sciences. Macquarie University; AustraliaFil: Gordillo, Sandra. CICTERRA. Universidad Nacional de Córdoba; ArgentinaFil: Boretto, Gabriela M.. CICTERRA. Universidad Nacional de Córdoba; ArgentinaFil: Malve, Mariano E.. Facultad de Ciencias Exactas, Físicas y Naturales. Universidad Nacional de Córdoba; Argentin

Uso de indicadores para evaluar la sustentabilidad ecológica en agroecosistemas de secano, San Juan, Argentina

El objetivo de este trabajo fue evaluar la sustentabilidad ecológica de agroecosistemas de secano de pequeños productores rurales mediante la construcción de indicadores a escala predial. El estudio se realizó en 5 (AE) ubicados en el departamento de 25 de Mayo, provincia de San Juan y corresponde con el sitio Ramsar Lagunas de Guanacache. Para la construcción de indicadores se hicieron entrevistas semi estructuradas, recorridas conjuntas con el productor de cada AE, se tomaron muestras de agua por cada fuente relevada y se realizaron transectas fisinómico estructurales para conocer el estado del recurso forrajero. Los resultados indican que AE 4 y 5 son sistemas que alcanzan la sustentabilidad ecológica mientras que los demás, se encuentran en una situación crítica. La metodología utilizada es fácil de aplicar, es de bajo costo y permite detectar las variables que ponen en riesgo la sustentabilidad ecológica de los agroecosistemas.Fil: Carmona Crocco, Julieta. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza - San Juan. Estación Experimental Agropecuaria San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Tapia Balmaceda, Raúl Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza - San Juan. Estación Experimental Agropecuaria San Juan; ArgentinaFil: Martinelli, Mariana. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza - San Juan. Estación Experimental Agropecuaria San Juan; Argentina. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina1º Congreso Argentino de AgroecologìaMendozaArgentinaSociedad Científica Latinoamericana de Agroecologí

Infiltration rate and base infiltration in two shrub communities of the hyper arid desert of San Juan (Argentina)

En las regiones áridas y semiáridas, el agua representa el principal factor limitante para la productividad primaria neta y en consecuencia determina el funcionamiento del ecosistema. La fracción de precipitación que ingresa al suelo y queda disponible para las plantas, depende de la interacción entre la precipitación, la vegetación y el suelo. Las comunidades arbustivas de zonas áridas son de gran importancia no sólo por su capacidad de mantener la estructura física del paisaje, sino también por su contribución a la dinámica hídrica del ecosistema. El objetivo del trabajo fue evaluar la velocidad de infiltración e infiltración base en dos comunidades arbustivas del desierto híper árido de San Juan, Argentina. Se identificaron y caracterizaron, con técnicas de teledetección y trabajo de campo, las comunidades arbustivas presentes en el área de estudio. Las mediciones de velocidad de infiltración e infiltración básica se efectuaron mediante el método del anillo simple. Con los valores obtenidos, se construyeron las curvas de infiltración para las comunidades vegetales arbustivas y también para suelo libre de vegetación. Se reconocieron dos comunidades arbustivas, Lamaral y Zampal. Respecto de la infiltración, se encontró que la velocidad de infiltración media fue 1.98 veces mayor en los arbustales en comparación con suelo desnudo. Para la infiltración básica no se encontraron diferencias estadísticamente significativas entre las comunidades, pero si entre estas y el suelo desnudo. Los resultados aquí reportados pueden ser empleados como insumos para la elaboración o ajuste de modelos hidrológicos y para el manejo de los matorrales de San Juan.In arid and semi-arid regions, water represents the main limiting factor for net primary productivity and, consequently, determines the functioning of the ecosystem. The fraction of precipitation that enters the soil and remains available to plants depends on the interaction between precipitation, vegetation and soil. The shrub communities of arid zones are of great importance not only for their ability to maintain the physical structure of the landscape, but also for their contribution to the hydric dynamics of the ecosystem. The objective of the work was to evaluate the infiltration rate and base infiltration in two shrub communities of the hyper-arid desert of San Juan, Argentina. The shrub communities present in the study area were identified and characterized with remote sensing techniques and field work. Infiltration rate and basic infiltration measurements were made by the simple ring method. With the values obtained, the infiltration curves were constructed for the shrubby plant communities and also for soil free of vegetation. Two bush communities, Lamaral and Zampal, were recognized. Regarding infiltration, it was found that the mean infiltration speed was 1.98 times higher in the shrubs compared to bare soil. For basic infiltration, no statistically significant differences were found between the communities, but there were differences between them and the bare soil. The results reported here can be used as inputs for the elaboration or adjustment of hydrological models and for the management of the San Juan scrubs.Fil: Tapia Balmaceda, Raúl Esteban. Universidad Nacional de San Juan; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Carmona Crocco, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; ArgentinaFil: Martinelli, M.. Universidad Nacional de San Juan; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentin

Impact of circulating tumor DNA mutant allele fraction on prognosis in RAS‐mutant metastatic colorectal cancer

Metastatic colorectal cancer; RAS analysis; Prognostic biomarkerCáncer colorrectal en metástasis; Análisis RAS; Biomarcador como pronósticoCàncer colorectal en metàstasi; Anàlisi RAS; Biomarcador com a pronòsticDespite major advances in the treatment of metastatic colorectal cancer (mCRC), the survival rate remains very poor. This study aims at exploring the prognostic value of RAS‐mutant allele fraction (MAF) in plasma in mCRC. Forty‐seven plasma samples from 37 RAS‐mutated patients with nonresectable metastases were tested for RAS in circulating tumor DNA using BEAMing before first‐ and/or second‐line treatment. RAS MAF was correlated with several clinical parameters (number of metastatic sites, hepatic volume, carcinoembryonic antigen, CA19‐9 levels, primary site location, and treatment line) and clinical outcome [progression‐free survival (PFS) and overall survival (OS)]. An independent cohort of 32 patients from the CAPRI‐GOIM trial was assessed for clinical outcome based on plasma baseline MAF. RAS MAF analysis at baseline revealed a significant correlation with longer OS [Hazard ratios (HR) = 3.514; P = 0.00066]. Patients with lower MAF also showed a tendency to longer PFS, although not statistically significant. Multivariate analysis showed RAS MAFs as an independent prognostic factor in both OS (HR = 2.73; P = 0.006) and first‐line PFS (HR = 3.74; P = 0.049). Tumor response to treatment in patients with higher MAF was progression disease (P = 0.007). Patients with low MAFs at baseline in the CAPRI‐GOIM group also showed better OS [HR = 3.84; 95% confidence intervals (CI) 1.5–9.6; P = 0.004] and better PFS (HR = 2.5; 95% CI: 1.07–5.62; P = 0.033). This minimally invasive test may help in adding an independent factor to better estimate outcomes before initiating treatment. Further prospective studies using MAF as a stratification factor could further validate its utility in clinical practice.This work was supported partially by the Instituto de Salud Carlos III (Ministerio de Economia y Competitividad) and `Fondo Europeo de Desarrollo Regional (FEDER), una manera de hacer Europa' grants [FIS PI12-01589 to RS] and RETICC Cancer