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Odonata (Insecta) de tres cuencas en la costa de Chiapas: lista de especies y registro nuevo

Perla Alonso_EguíaLis (2015, [Artículo])

Se recolectaron 512 adultos del orden Odonata, que corresponden a 41 especies. Estas se agrupan en 24 géneros que pertenecen a las familias Calopterygidae, Coenagrionidae y Libellulidae. El porcentaje de individuos recolectados fue del 58.54% para el suborden Zygoptera y 41.46% para el suborden Anisoptera. La representatividad del muestreo de las especies esperadas a lo largo de todo el estudio varió de 75.6% para septiembre hasta 95.2% para enero. Se registra por primera vez a la especie Brachymesia herbida para Chiapas. La especie dominante fue Argia pulla, la cual se recolectó en todos los sitios. Mediante el índice de similitud de Morisita-Horn, se agruparon las especies y se relacionaron con las características del ambiente en las subregiones: alta, media y baja.

Libélulas Chiapas BIOLOGÍA Y QUÍMICA

Propiedades fisicoquímicas del aceite de semillas de Jatropha curcas de poblaciones silvestres en México

NIDIA ARAIZA LIZARDE MIGUEL ANGEL ANGULO ESCALANTE TEODORO REYNOSO GRANADOS MARIA MAGDALENA ORTEGA NIEBLAS Lilia Alcaráz Meléndez Pedro Cruz Hernández (2015, [Artículo])

"Existe la necesidad de estudiar fuentes renovables de energía a partir de plantas oleaginosas con este potencial. La semilla de Jatropha curca se caracteriza por su alto contenido de aceite. En México solo existen estudios enfocados en evaluar las propie-dades fisicoquímicas del aceite de J. curcas silvestre y cultivada en la región sur. El objetivo de este trabajo, fue evaluar las propiedades fisicoquímicas del aceite de J. curcas silvestre en tres ecotipos del estado de Sinaloa (noroeste de México) y su aplicación en la elaboración de biodiesel. Los resultados obtenidos fueron que el contenido de aceite del germen fue de 52 a 56%. La viscosidad, densidad específica, índice de acidez, peróxido, yodo y refracción no mostraron diferencias significativas en las semillas colectadas en los tres ecotipos en estudio. Los ácidos grasos saturados más abundantes fueron el palmítico (4 a 6%) y esteárico (3 a 4%). Los ácidos grasos insaturados más abundantes fueron el oleico (44 a 46%) y linoleico (42 a 44%). Las características fisicoquímicas del aceite de J. curcas de Sinaloa son similares a las del sur de México y otros países, esto sugiere que el germoplasma del noroeste del país podría ser considerado para su conservación, aprovechamiento racional y producción de biodiesel."

"The need for studying sources of renewable energy is important starting from potential oleaginous plants. Jatropha curcas seed is characterized by its high oil content. In Mexico studies are focused on evaluating the physicochemical properties of J. curcas oil in wild plants cultivated in the southern region. The objective of this study was to evaluate these properties in three ecotypes of wild J. curcas of Sinaloa and their oil application in biodiesel production. The oil content of the germ was found to be 52 to 56%. Viscosity, density, acidity index, peroxide, iodine, and refraction showed no signif-icant differences in the seeds collected from the three ecotypes in our study. The most abundant saturated fatty acids were palmitic (4 to 6%) and stearic (3 to 4%). The most abundant unsaturated fatty acids were oleic (44 to 46%) and linoleic (42 to 44%). Physi-cochemical characteristics of J. curcas oil of Sinaloa specimens are similar to those of southern Mexico and other countries, which suggest that the germplasm of the north-western part of the country could be considered for conservation, rational utilization, and biodiesel production."

Fatty acid, ecotype, fatty acid, physicochemical analysis Ácidos grasos, biodiesel, ecotipos, análisis fisicoquímicos, Jatropha BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOQUÍMICA LÍPIDOS LÍPIDOS

Near-real-time welfare and livelihood impacts of an active war: Evidence from Ethiopia

Kibrom  Abay Guush Berhane Jordan Chamberlin Mehari Hiluf Abay (2023, [Artículo])

Ethiopia recently experienced a large-scale war that lasted for more than two years. Using unique High-Frequency Phone Survey (HFPS) data, which span several months before and after the outbreak of the war, this paper provides evidence on the immediate impacts of the conflict on households’ food security. We also assess potential mechanisms and evaluate impacts on proximate outcomes, including on livelihood activities and access to food markets. We use difference-in-differences and two-way fixed effects estimation to compare trends across affected and unaffected regions (households) and before and after the outbreak of the war. Seven months into the conflict, we find that the war was associated with a 37 percentage points increase in the probability of moderate to severe food insecurity. Using the Armed Conflict Location and Event Data (ACLED), we show that exposure to an additional battle leads to a 1 percentage point increase in the probability of moderate or severe food insecurity. The conflict was associated with significant reduction in access to food through supply chain disruptions and by curtailing non-farm livelihood activities. Non-farm and wage related activities were affected the most, whereas farming activities were relatively more resilient. Our estimates, which likely underestimate the true average effects on the population, constitute novel evidence on the near-real-time impacts of large-scale conflict. Our work highlights the potential of HFPS to monitor active and large-scale conflicts, especially in contexts where conventional data sources are not immediately available.

Phone Surveys CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA WAR CONFLICTS FOOD SECURITY LIVELIHOODS

Calidad del agua de un lago urbano en la Ciudad de México (2015-abril 2017)

Ana Cecilia Tomasini Ortiz MERCEDES ESPERANZA RAMIREZ CAMPEROS Lina Cardoso (2017, [Memoria de congreso])

El lago urbano estudiado, está situado al oeste de la Ciudad de México. La problemática de la eutrofización del lago se agudizó y el lago presentó algunas características del estado de hipertrofía por su someridad y circulación limitada, falta de estratificación, regímenes de nutrientes y oxígeno no balanceado y productividad muy alta, tomando como parámetro concentraciones de Clorofila a. Por tal motivo, después de haber monitoreado el lago durante 2015 y hasta marzo de 2015, se adaptó una planta piloto de coagulación-floculación alimentada con agua del mismo lago para el retiro de algas.

Lagos Zonas urbanas Eutroficación Calidad del agua INGENIERÍA Y TECNOLOGÍA

Economic valuation of climate induced losses to aquaculture for evaluating climate information services in Bangladesh

Peerzadi Rumana Hossain T.S Amjath-Babu Timothy Joseph Krupnik (2023, [Artículo])

Very little research has focused on climate impacts on aquaculture and the potential of climate information services (CIS) for aquaculture to support sustainable development goals 2030 (SDGs)1. This study represents an effort to bridge this gap by conducting a first ex-ante economic evaluation of CIS for aquaculture in Bangladesh by semi-automating the extraction of data on climate-induced fish losses during 2011 to 2021 from popular online newspaper articles and corroborating them with available government and satellite datasets. During this period, Bangladesh faced an estimated loss of around 140 million USD for hatcheries, open water fish and shrimp. When validated with a year of country-wide official data on climate-induced economic losses to aquaculture, the damage reported from these media sources is approximately 10 percent of actual losses. Given this rule of thumb, the potential economic value of aquacultural CIS could be up to USD14 million a year, if 10 percent of the damage can be offset by appropriate services through a range of multi-sector efforts to establish and extend these services to farmers at scale.

Climate Information Services Newspaper Scraping CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA LOSSES AQUACULTURE CLIMATE SERVICES SUSTAINABLE DEVELOPMENT GOALS

Mapping crop and livestock value chain actors in Mbire and Murehwa districts in Zimbabwe

Hambulo Ngoma Moti Jaleta Frédéric Baudron (2023, [Documento de trabajo])

We conducted a preliminary value chain actors mapping for major crops grown and livestock kept by smallholder farmers in Mbire and Murehwa districts of Zimbabwe. Accordingly, in this report we mapped value chain actors for 11 crops and livestock commodities: namely, sorghum, cotton, sesame, maize, groundnut, sweet-potato, vegetables (tomato and onion), cattle, goats, poultry, and honey/beekeeping. Except sesame from Mbire, most of the crop and livestock commodities are channeled to the main markets in Harare and Marondera for Murehwa. Sesame is smuggled to Mozambique and the market is mainly dependent on middlemen. The Grain Market Board (GMB) is the major actor in sorghum and maize marketing in both districts. Groundnut is sold to both rural and urban consumers after processing it to peanut butter locally within the production zones. Goats and cattle are mostly supplied to the Harare market by middlemen collecting these livestock from village markets and moving door-to-door to buy enough quantity to transport to Harare. Honey production and marketing is still at its initial stage through the support of HELP from Germany and the Zimbabwe Apiculture Trust projects. Long dry season is a challenge in honey production. The Pfumvudza program supported by the Presidential free input scheme helped in introducing and scaling conservation agriculture practices in Zimbabwe. Though there is strong integration of crop-livestock systems at both districts, the level of manure use is gradually decreasing because farmers receive chemical fertilizer support from the Pfumvudza program and applying manure to crop fields is labor-intensive. The input supply system is more competitive in Murehwa district where there are quite several input suppliers in town. The possible interventions that favor agroecological transitions are: (1) honey processing plants and supply of beehives to potential areas, (2) encouraging manure use in crop production, possibly linking it to the basins preparation requirement to be eligible for the presidential input subsidy scheme, (3) support the organic vegetable production initiatives and explore market segments in Harare paying premium prices for certified organic products, (4) Expedite payment systems in sorghum and maize marketing with GMB, and (5) sesame production with agroecologically friendly agronomy and improve markets.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA VALUE CHAINS CROPS LIVESTOCK SMALLHOLDERS SUPPLY CHAINS