A SWIR based algorithm to retrieve total suspended matter in extremely turbid waters

In ocean colour remote sensing, the use of Near Infra Red (NIR) spectral bands for the retrieval of Total Suspended Matter (TSM) concentration in turbid and highly turbid waters has proven to be successful. In extremely turbid waters (TSMN 100 mgL−1) however, these bands are less sensitive to increases in TSM. Here it is proposed to use Short Wave Infra Red (SWIR) spectral bands between 1000 and 1300 nm for these extreme cases. This SWIR spectral region is subdivided into two regions, SWIR-I (1000 nm to 1200 nm) and SWIR-II (1200 nm to 1300 nm) which correspond to local minima in the pure water absorption spectrum. For both spectral regions the water reflectance signal was measured in situ with an ASD spectrometer in three different extremely turbid estuarine sites: Scheldt (Belgium), Gironde (France), and Río de la Plata (Argentina), along with the TSMconcentration.A measurable water reflectance was observed for all sites in SWIR-I, while in the SWIR-II region the signal was not significant compared to the Signal-to-Noise Ratio (SNR) of current Ocean Colour (OC) sensors. For the spectral band at 1020 nm (present in Ocean and Land Colour Instrument ? OLCI, onboard Sentinel-3) and at 1071 nm, an empirical single band TSM algorithm is defined which is valid for both the Gironde and Scheldt estuarine sites. This means that a single algorithm can be applied for both sites without expensive recalibration.The relationship between TSM and SWIR reflectance at 1020 and 1071 nm is linear and did not show any saturation for the concentrations measured here (up to 1400 mg L−1), while saturation was observed for the NIR wavelengths, as expected. Hence, for extremely turbid waters it is advised to switch from NIR to SWIR-I wavelengths to estimate TSM concentration. This was demonstrated for an airborne hyperspectral dataset (Airborne Prism Experiment, APEX) from the Gironde estuary having several spectral bands in the SWIR-I. The empirical single band SWIR TSM algorithm was applied to the atmospherically corrected scene providing a TSM concentration map of the Gironde from mouth to more upstream with concentrations expected in this region ranging from a few to several hundreds mg L−1. These results, i.e. the existence of a single relationship for the Scheldt and Gironde, not showing any decrease of sensitivity, highlights the importance of having SWIR bands in future ocean colour sensors for studying extremely turbid rivers, coastal areas and estuaries in the world. A further implication of these results is that there is a TSMlimit for application of atmospheric correction algorithms which assume zero SWIR marine reflectance. That limit is defined here as function of wavelength and sensor noise level.Fil: Knaeps, E.. Flemish Institute for Technological Research (VITO); BélgicaFil: Ruddick, K. G.. Flemish Institute for Technological Research ; BélgicaFil: Doxaran, D.. Laboratoire d; FranciaFil: Dogliotti, Ana Inés. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Nechad, B.. Royal Belgian Institute for Natural Sciences (RBINS); BélgicaFil: Raymaekers, D.. Flemish Institute for Technological Research; BélgicaFil: Sterckx, S.. Flemish Institute for Technological Research; Bélgic

Exploración de alternativas para el desarrollo sostenible de sistemas de producción hortícola-ganaderos familiares en el sur de Uruguay

La sostenibilidad de la mayoría de los predios hortícolas familiares en el sur de Uruguay está amenazada por ingresosinsuficientes y por el deterioro de los recursos naturales. En este estudio se cuantificó el efecto de la inclusión de diferentesactividades de producción ganadera en la estructura y en los resultados económico-productivos y ambientales de diferentestipos de sistemas de producción (predios) hortícolas. Se realizó un estudio exploratorio a escala predial con modelos desimulación utilizando dos predios como estudio de caso. Los resultados sugieren que la inclusión de actividades de producciónganadera en los sistemas de producción hortícolas es un factor determinante para reducir la erosión promedio del áreacultivada. Para reducir la erosión el modelo diseñó predios que reducen el área de hortalizas al tiempo que expanden larotación forrajera. Como consecuencia de esto, también se redujo el ingreso familiar (IF) entre 12 % y 31 % según el casoestudiado. Sin embargo, pudimos diseñar sistemas de producción con erosión menor a la tolerable para el tipo de suelo e IFmayor al objetivo, en los dos predios. De las actividades ganaderas evaluadas las más apropiadas para incluir en predios hortícolasson el engorde de novillos o vaquillonas en ciclos de 14 a 18 meses, debido al menor costo para reposición de animales y al menoruso de concentrados, lo que disminuye las necesidades de capital y la dependencia de insumos externos

The application of ecologically intensive principles to the systemic redesign of livestock farms on native grasslands: A case of co-innovation in Rocha, Uruguay

CONTEXT: Family-run cow-calf farms based on native grasslands exhibit low economic and social sustainability, as reflected in low family incomes and high workloads. Experimental results have shown that pasture–herd interaction management could improve native grasslands and animal productivity OBJECTIVE: This paper analyzes the extent to which the sustainability of family-run livestock farms based on native grasslands could be enhanced by a systemic redesign informed by ecological intensification practices. The research questions address the initial state of farm sustainability, key bottlenecks to improving farm sustainability, and changes in sustainability criteria achieved over three years of farm redesign. METHODS: The study was executed as part of a multi-level co-innovation project in Uruguay in which a team of scientist-practitioners and seven farm families participated in farm characterization, diagnosis, and redesign. The farm characterization took the form of indicators to describe the farms’ management and bio-physical subsystems. Redesign plans were negotiated between the research team and the farmers. Frequent monitoring and evaluation cycles enabled finetuning across the years of implementation. RESULTS AND CONCLUSION: Improvements were observed in the economic indicators gross margin (+55%), return to labor (+71%), and family income (+53%) and in the social indicator workload ( 22%), and the environmental indicators bird diversity and ecosystem integrity index were maintained or increased slightly. These changes were explained by the uptake of coherent sets of ecological intensification practices causing changes in forage height (+30%), forage allowance (+69%), pregnancy (+22), weight of weaning calf per mating cow (+32%), and presence of tussocks (+65%). Ecological intensification principles resulted in synergistic positive effects between productivity–biodiversity tradeoffs and the scope for enhanced farm resilience and stability. SIGNIFICANCE: Cow-calf family-run farms can be transformed to produce positive environmental and social effects and viable economic results. The implementation of projects in a co-innovation context may be taken as a guide to scaling up and scaling out the ecological intensification of livestock production on native grasslands, contributing to an extension system at the national level with the aim of improving cow-calf systems sustainability.Estación Experimental Agropecuaria BarilocheFil: Ruggia, Andrea. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Dogliotti, Santiago. Universidad de la República. Facultad de Agronomía. Departamento de Produccion Vegetal; UruguayFil: Aguerre, Maria Veronica. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Albicette, Maria Marta. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Blumetto, Oscar. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Cardozo, Geronimo. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Pasturas y Forrajes. Estacion Experimental INIA Treinta y Tres; UruguayFil: Leoni, Carolina. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Quintans, Graciela. Instituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Carne y Lana. Estacion Experimental INIA Treinta y Tres; UruguayFil: Scarlato, Santiago. nstituto Nacional de Investigacion Agropecuaria (INIA). Programa Nacional de Investigacion en Produccion Familiar. Estacion Experimental INIA Las Brujas; UruguayFil: Tittonell, Pablo Adrian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Tittonell, Pablo Adrian. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Rossing, Walter A.H. Wageningen University and Research. Farming Systems Ecology, Plant Sciences Group; Holand