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Datación de sedimentos recientes utilizando isótopos radioactivos en el río Verde, en el estado de Oaxaca, México

Dating of recent sediments using radioactive isotopes in the Rio Verde, Oaxaca state, Mexico

José Alfredo González Verdugo EDITH ROSALBA SALCEDO SANCHEZ MARIA JOSELINA CLEMENCIA ESPINOZA AYALA MANUEL MARTINEZ MORALES (2013, [Artículo])

Con objeto de conocer la evolución de los procesos sedimentarios en la parte baja del río Verde, Oaxaca, se realizaron mediciones en dos núcleos de sedimentos. El fechado y determinación de la tasa de sedimentación, se realizó utilizando los isótopos radioactivos Plomo-210 y Cesio-137, que sirven como indicadores de períodos de deposición de los últimos 100 años. La velocidad de sedimentación en el Río Verde obtenida por medio del isótopo Pb -210 es 0.69 a 0.89 cm/año. Por otro lado, la velocidad de sedimentación en la zona de estudio mediante el isótopo Cs-137 es del orden de 0.61 cm/año y 0.87 cm/año. El método de Cesio-137 proporciona marcadores distintivos de eventos, mientras que el método de Plomo-210 proporciona pendientes de concentración, que al aplicarse de manera conjunta proporcionan una validación de ambos métodos. En este estudio, los dos métodos coinciden en los valores de sedimentación para la zona del Río Verde. Los resultados de este trabajo permiten conocer la dinámica de los procesos de transporte de sedimentos en la zona, información que resulta útil para la planeación de obras hidráulicas y estimación de los impactos ambientales, así como la implementación de las medidas de mitigación correspondientes.

Sedimentación Datación Isótopos radiactivos Marcadores Morfología de ríos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Appraisal of complementarity of subsurface drip fertigation and conservation agriculture for physiological performance and water economy of maize

C.M. Parihar Hari Sankar Nayak Dipaka Ranjan Sena Renu Pandey Mahesh Gathala ML JAT (2023, [Artículo])

The Indo-Gangetic Plains (IGP) in north-west (NW) India are facing a severe decline in ground water due to prevalent rice-based cropping systems. To combat this issue, conservation agriculture (CA) with an alternative crop/s, such as maize, is being promoted. Recently, surface drip fertigation has also been evaluated as a viable option to address low-nutrient use efficiency and water scarcity problems for cereals. While the individual benefits of CA and sub-surface drip (SSD) irrigation on water economy are well-established, information regarding their combined effect in cereal-based systems is lacking. Therefore, we conducted a two-year field experiment in maize, under an ongoing CA-based maize-wheat system, to evaluate the complementarity of CA with SSD irrigation through two technological interventions–– CA+ (residue retained CA + SSD), PCA+ (partial CA without residue + SSD) – at different N rates (0, 120 and 150 kg N ha-1) in comparison to traditional furrow irrigated (FI) CA and conventional tillage (CT) at 120 kg N ha-1. Our results showed that CA+ had the highest grain yield (8.2 t ha-1), followed by PCA+ (8.1 t ha-1). The grain yield under CA+ at 150 kg N ha-1 was 27% and 30% higher than CA and CT, respectively. Even at the same N level (120 kg N ha-1), CA+ outperformed CA and CT by 16% and 18%, respectively. The physiological performance of maize also revealed that CA+ based plots with 120 kg N ha-1 had 12% and 3% higher photosynthesis rate at knee-high and silking, respectively compared to FI-CA and CT. Overall, compared to the FI-CA and CT, SSD-based CA+ and PCA+ saved 54% irrigation water and increased water productivity (WP) by more than twice. Similarly, a greater number of split N application through fertigation in PCA+ and CA+ increased agronomic nitrogen use efficiency (NUE) and recover efficiency by 8–19% and 14–25%, respectively. Net returns from PCA+ and CA+ at 150 kg N ha-1 were significantly higher by US$ 491 and 456, respectively than the FI-CA and CT treatments. Therefore, CA coupled with SSD provided tangible benefits in terms of yield, irrigation water saving, WP, NUE and profitability. Efforts should be directed towards increasing farmers’ awareness of the benefits of such promising technology for the cultivating food grains and commercial crops such as maize. Concurrently, government support and strict policies are required to enhance the system adaptability.

Net Returns Subsurface Drip Irrigation Subsurface Drip Fertigation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA EFFICIENCY GRAIN NITROGEN PHOTOSYNTHESIS PHYSIOLOGY WATER SUPPLY CONSERVATION AGRICULTURE CONVENTIONAL TILLAGE FERTIGATION GROUNDWATER NITROGEN-USE EFFICIENCY WATER PRODUCTIVITY

Disruptive approach to integrate data in a digital environment: progress report CIMMYT-Bluenumber 2023

Andrea Gardeazabal (2023, [Documento de trabajo])

This report describes the process carried out a pilot project to evaluate a scalable disruptive approach to integrating data for agronomy research that also incentivizes sustainable production and enables traceability using open data sharing protocol with self-sovereign identity (SSI).

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA DIGITAL TECHNOLOGY DATA AGRICULTURAL RESEARCH