Freshwater exchanges and surface salinity in the Colombian basin, Caribbean Sea

Emilio Beier (2017, [Artículo])

Despite the heavy regional rainfall and considerable discharge of many rivers into the Colombian Basin, there have been few detailed studies about the dilution of Caribbean Surface Water and the variability of salinity in the southwestern Caribbean. An analysis of the precipitation, evaporation and runoff in relation to the climate variability demonstrates that although the salt balance in the Colombian Basin overall is in equilibrium, the area south of 12N is an important dilution sub-basin. In the southwest of the basin, in the region of the Panama-Colombia Gyre, Caribbean Sea Water is diluted by precipitation and runoff year round, while in the northeast, off La Guajira, its salinity increases from December to May by upwelling. At the interannual scale, continental runoff is related to El Niño Southern Oscillation, and precipitation and evaporation south of 12°N are related to the Caribbean Low Level Jet. During El Niño years the maximum salinification occurs in the dry season (December-February) while in La Niña years the maximum dilution (or freshening), reaching La Guajira Coastal Zone, occurs in the wet season (September-November). © 2017 Beier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

sea water, fresh water, Article, Caribbean, dilution, dry season, El Nino, environmental parameters, evaporation, freshwater exchange, geographic distribution, molecular weight, oscillation, precipitation, river basin, salinity, seasonal variation, s CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Dipole-wind interactions under gap wind jet conditions in the Gulf of Tehuantepec, Mexico: A surface drifter and satellite database analysis

MAURO WILFRIDO SANTIAGO GARCIA (2019, [Artículo])

Gap wind jets (Tehuano winds) trigger supersquirts of colder water and mesoscale asymmetric dipoles in the Gulf of Tehuantepec (GT). However, the effects of successive gap wind jets on dipoles and their effects inside eddies have not yet been studied. Based on the wind fields, geostrophic currents, and surface drifter dispersion, this research documented three dipoles triggered and modified by Tehuano winds. Once a dipole develops, successive gap wind jets strengthen the vortices, and the anticyclonic eddy migrates southwestward while the cyclonic eddy is maintained on the east side of the GT. During the wind relaxation stage, the cyclonic eddy may propagate westward, but due to the subsequent re-intensification of the Tehuano winds, the vortex could break down, as was suggested by surface drifter dispersion pattern and geostrophic field data. The effect of the Tehuano winds was evaluating via eddy-Ekman pumping. Under Tehuano wind conditions, Ekman downwelling (upwelling) inside the anticyclonic (cyclonic) eddies may reach ~ -2.0 (0.5) m d-1 and decrease as the wind weakens. In the absence of Tehuano winds, Ekman downwelling inside the anticyclonic eddy was ~ 0.1 (-0.1) m d-1. The asymmetry of downwelling and upwelling inside eddies during Tehuano wind events may be associated with Tehuano wind forcing. © 2019 Santiago-García et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

article, dipole, leisure, Mexico, cold, ecosystem, factual database, geographic mapping, hurricane, Mexico, satellite imagery, season, water flow, wind, sea water, Cold Temperature, Cyclonic Storms, Databases, Factual, Ecosystem, Geographic Mapping, CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Agricultura, agua y cambio climático en zonas áridas de México

SALVADOR EMILIO LLUCH COTA JUAN ALBERTO VELAZQUEZ ZAPATA César Nieto Delgado (2022, [Artículo])

"En este artículo se expone cómo a pesar de que la ciencia y la tecnología han permitido aumentar históricamente la productividad agrícola, hoy día existen grandes retos derivados del cambio climático y la crisis global de abastecimiento de agua. Se comentan algunas medidas de adaptación y manejo del recurso agua, con algunas referencias a nuestra realidad nacional, y se argumenta cómo el enfoque de Nexo, que implica la toma de decisiones sobre el uso del recurso agua de forma transectorial, representa una alternativa de adaptación al cambio climático."

Cambio climático, agricultura, agua, Nexo, adaptación Climate change, agriculture, water, nexus, adaptation CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CLIMATOLOGÍA CLIMATOLOGÍA REGIONAL CLIMATOLOGÍA REGIONAL

Corales vivos: diseño editorial como medio de divulgación científica en San Miguel, Cozumel

VÍCTOR IVÁN MORENO RODRÍGUEZ (2023, [Otro, Trabajo terminal, especialidad])

La Isla de Cozumel ha sido un lugar de cambios. De ser una isla ritual y de relajación –culto a la

diosa Ixchel– a ser un atractivo turístico. Sin embargo, Cozumel no sólo es objeto de diversión y

relajación, también de una abundante vida científica que ha logrado desarrollarse y coexistir con

la comunidad, formando parte tanto de sus pobladores como de sus visitantes, atrayendo a mucha

gente, no solo por su belleza, sino por su biodiversidad y su quehacer científico.

Hasta mediados de los años cincuenta (1950), la Isla de Cozumel pudiera considerarse poco

explorada y explotada; si bien hay indicios de culturas como la maya que la habían poblado tiempo

atrás (900 D.C.), así como de la intervención española, incluso antes de la llegada de Cortés a

América (1518), solo unos cuántos nativos, descendientes de mestizos escapando de la guerra de

castas la habitaban y explotaban sus recursos con base en la pesca y comercialización del cedro

(Sánchez, 2020).

Se cree que sus playas comenzaron a popularizarse a raíz de las declaraciones del buzo y

oceanógrafo francés Jacques-Yves Cousteau, quien consideraba a Cozumel como uno de los

mejores lugares para ejercer el buceo, ya que sus aguas turquesas otorgaban las condiciones ideales

para la exploración marina, tanto profesional como recreativa. Particularmente, una de las cosas

que más destacaba de Cozumel eran los arrecifes de coral.

Desde principios de los años ochenta, los arrecifes de coral en todo el mundo se encuentran

en una carrera contra reloj por su supervivencia. En particular, la barrera de corales

mesoamericana, de la cual forma parte Cozumel, sufrió episodios importantes del denominado

blanqueamiento o bleaching en 1983, 1998 y 2005, ya que sufrió una pérdida de alrededor del

cincuenta por ciento de corales vivos (Wilkinson, 2008).

A grandes rasgos, esta afección provoca que el pólipo del coral, que es el tejido vivo de la

colonia, se estrese y se vuelva transparente, dejando ver la estructura blanca calcificada (de ahí el nombre). Sin embargo, si las condiciones óptimas se restablecen relativamente rápido, los pólipos,

que conforman la parte superficial y viva del coral, pueden sobrevivir.

Por otro lado, una afección más reciente es la Enfermedad de Pérdida de Tejido de Coral

Duro (Stony Coral Tissue Loss Disease o SCTLD por sus siglas en inglés), documentada

inicialmente en las costas de Florida en 2014 y que se confirmó en las costas de México en 2018.

Dicha enfermedad es similar al blanqueamiento y se puede confundir. No obstante, el SCTLD es

mortal para determinadas especies, algunas de gran importancia ecológica por ser constructoras de

arrecifes, como los corales cerebro (Pseudodiploria strigosa), el coral cuerno de alce (Acropora

Palmata) entre otros, pudiendo matar una colonia entera en cuestión de semanas. Desde 2018 a la

actualidad, esta enfermedad se ha logrado extender por toda la región sur de México, la cual forma

parte del Sistema Arrecifal Mesoamericano (SAM), que se extiende desde la Península de Yucatán

hasta Honduras.

CIENCIAS SOCIALES DEMOGRAFÍA

Movements of scalloped hammerhead sharks (Sphyrna lewini) at Cocos Island, Costa Rica and between oceanic islands in the Eastern Tropical Pacific

Elena Nalesso (2019, [Artículo])

Many species of sharks form aggregations around oceanic islands, yet their levels of residency and their site specificity around these islands may vary. In some cases, the waters around oceanic islands have been designated as marine protected areas, yet the conservation value for threatened shark species will depend greatly on how much time they spend within these protected waters. Eighty-four scalloped hammerhead sharks (Sphyrna lewini Griffith & Smith), were tagged with acoustic transmitters at Cocos Island between 2005–2013. The average residence index, expressed as a proportion of days present in our receiver array at the island over the entire monitoring period, was 0.52±0.31, implying that overall the sharks are strongly associated with the island. Residency was significantly greater at Alcyone, a shallow seamount located 3.6 km offshore from the main island, than at the other sites. Timing of presence at the receiver locations was mostly during daytime hours. Although only a single individual from Cocos was detected on a region-wide array, nine hammerheads tagged at Galapagos and Malpelo travelled to Cocos. The hammerheads tagged at Cocos were more resident than those visiting from elsewhere, suggesting that the Galapagos and Malpelo populations may use Cocos as a navigational waypoint or stopover during seasonal migrations to the coastal Central and South America. Our study demonstrates the importance of oceanic islands for this species, and shows that they may form a network of hotspots in the Eastern Tropical Pacific. © 2019 Nalesso et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

article, Cocos Island, human, monitoring, nonhuman, resident, shark, South America, animal, Costa Rica, environmental protection, island (geological), movement (physiology), physiology, season, shark, Animals, Conservation of Natural Resources, Costa CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Distribución y riesgo ecológico por la contaminación de metales en el acuífero de la ruta de los cenotes de Puerto Morelos, Q. Roo

GABRIELA PINEDA GARCIA (2023, [Tesis de maestría])

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO HIDROLOGÍA AGUAS SUBTERRÁNEAS AGUAS SUBTERRÁNEAS

Assessing the Response of Nematode Communities to Climate Change-Driven Warming: A Microcosm Experiment

RUTH GINGOLD WERMUTH (2013, [Artículo])

Biodiversity has diminished over the past decades with climate change being among the main responsible factors. One consequence of climate change is the increase in sea surface temperature, which, together with long exposure periods in intertidal areas, may exceed the tolerance level of benthic organisms. Benthic communities may suffer structural changes due to the loss of species or functional groups, putting ecological services at risk. In sandy beaches, free-living marine nematodes usually are the most abundant and diverse group of intertidal meiofauna, playing an important role in the benthic food web. While apparently many functionally similar nematode species co-exist temporally and spatially, experimental results on selected bacterivore species suggest no functional overlap, but rather an idiosyncratic contribution to ecosystem functioning. However, we hypothesize that functional redundancy is more likely to observe when taking into account the entire diversity of natural assemblages. We conducted a microcosm experiment with two natural communities to assess their stress response to elevated temperature. The two communities differed in diversity (high [HD] vs. low [LD]) and environmental origin (harsh vs. moderate conditions). We assessed their stress resistance to the experimental treatment in terms of species and diversity changes, and their function in terms of abundance, biomass, and trophic diversity. According to the Insurance Hypothesis, we hypothesized that the HD community would cope better with the stressful treatment due to species functional overlap, whereas the LD community functioning would benefit from species better adapted to harsh conditions. Our results indicate no evidence of functional redundancy in the studied nematofaunal communities. The species loss was more prominent and size specific in the HD; large predators and omnivores were lost, which may have important consequences for the benthic food web. Yet, we found evidence for alternative diversity-ecosystem functioning relationships, such as the Rivets and the Idiosyncrasy Model. © 2013 Gingold et al.

aquaculture, article, bacterivore, benthos, biodiversity, biomass, climate, community dynamics, controlled study, ecosystem, environmental temperature, microcosm, nematode, nonhuman, population abundance, species diversity, species richness, taxonomy CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Uso del cártamo (Carthamus tinctorius L.) como ingrediente en alimentos para juveniles del camarón Litopenaeus vannamei

ALFONSO GALICIA GONZALEZ (2009, [Tesis de doctorado])

Debido a los altos costos e incertidumbre en el abasto de la harina de pescado y pasta de soya, en los últimos años se han buscado alternativas que puedan sustituirlos sin tener un efecto negativo en el crecimiento de los camarones en el cultivo. En el presente trabajo se realizó un estudio para evaluar el valor nutricional del cártamo (Carthamus tinctorius) como fuente proteica en alimentos para juveniles de camarón blanco del Pacífico Litopenaeus vannamei. El primer capítulo comprende el estudio de la caracterización de tres productos de cártamo (HIC; Harina Integral de Cártamo, PCB; Pasta de cártamo baja en proteína y PCA; Pasta de cártamo alta en proteína) en base a su composición de nutrientes y algunos factores antinutricionales (hemaglutininas, saponinas, actividad uréasica, aflatoxinas e inhibidor de tripsina). Los productos de cártamo tuvieron un contenido de proteína entre 20.6 y 36.8%. La harina integral fue la que presentó el mayor nivel de extracto etéreo 31%, mientras que las pastas tuvieron un nivel bajo (1.8-1.0%). El contenido de fibra en el cártamo fue alto (17-23%). Los aminoácidos más abundantes en los productos de cártamo fueron el ácido aspártico y glutámico, en contraste los menos abundantes fueron lisina y metionina. Los ácidos grasos más abundantes fueron el ácido oleico, el linoleico, el palmítico y el estéarico. El contenido de calcio de los productos de cártamo varió de 0.25 a 0.42%, mientras que el contenido de fósforo varió del 0.23 a 0.25%. No se encontraron los factores antinutricionales buscados, a excepción del inhibidor de tripsina que tuvo valores bajos (7.56 UTI/mg de muestra). No se encontraron diferencias significativas en los coeficientes de utilización digestiva aparente (CUDA) de materia seca y carbohidratos de los productos de cártamo; sin embargo, sí se encontraron diferencias en los CUDA de proteína, lípidos (CUDAl) y de energía digestible (CUDAe). La actividad de las enzimas digestivas de camarones que fueron alimentados con productos de cártamo mostró un incremento en proteinasas generales y quimotripsina. La atractabilidad y el consumo de los alimentos con un 30% de inclusión de los productos de cártamo se vieron afectadas negativamente en los camarones [...]

In recent years, alternatives to fish and soybean meals in aquacultural feeds that do not have negative effects on growth of cultivated shrimp have been intensively studied in an effort to reduce the high costs and uncertainty in supplies. In this study, the nutritional value of safflower (Carthamus tinctorius) meal as a protein source in diets for juveniles Pacific whiteleg shrimp (Litopenaeus vannamei) was investigated. Initially, characterization of three safflower meals (i.e. WSM; whole safflower meal, LPSM; low-protein safflower meal and HPSM; high-protein safflower meal), focusing on chemical composition and antinutritional factors (hemaglutinine, saponine, ureasic activity, aflatoxin, and trypsin inhibitor) was conducted. Protein content ranged from 20.6 to 36.8%. Whole safflower meal contained the highest level of lipids (31%); lipids in the other safflower meals were as low as 1.0–1.8%. Fiber content was high (17–23%). The most abundant amino acids were aspartic and glutamic acids and lysine and methionine were less abundant. Oleic, linoleic, palmitic, and stearic fatty acids were present in greatest amounts. Calcium content ranged from 0.25–0.42% and phosphorus content ranged from 0.23–0.25%. Anti-nutritional factors were not found in the analyses, except for trypsin inhibitor, with values as low as 7.56 UTI mg–1 per sample. No significant differences between the apparent digestibility coefficients (ADC) for dry matter and carbohydrates in safflower meals were detected; however, protein ADC, lipid ADC, and energy ADC were different. Total proteinase and chymotrypsin increased significantly in diets where safflower meals were included. Atractability and consumption of feed with 30% safflower meals appeared to have negative effects on the juveniles [...]

atractabilidad; camarón; cártamo; Carthamus tinctorius; digestibilidad; enzimas digestivas; factores antinutricionales; Litopenaeus vannamei CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA ACUICULTURA MARINA OCEANOGRAFÍA ACUICULTURA MARINA

Spatial Effects of Urban Transport on Air Pollution in Metropolitan Municipalities of Mexico

GERZAIN AVILES POLANCO Marco Antonio Almendárez Hernández Luis Felipe Beltrán Morales Alfredo Ortega Rubio (2022, [Artículo])

"The objective of this work was to estimate the local effects and spatial spillover effects of the number of vehicles, use of urban public transport, and population density on nitrogen oxide emissions for 405 metropolitan municipalities in Mexico in 2016. To this end, a Spatial Durbin Model was estimated. We found positive direct effects of the number of vehicles and population density and negative direct effects of the use of urban public transport. The number of vehicles in circulation had negative spillover effects on the nitrogen oxide emissions of neighboring municipalities. These results indicate that the design of public policy programs aimed at reducing air pollution in Mexico should be based on coordination across metropolitan municipalities."

private car transportation, air pollution, nitrogen oxide emissions, spatial spillover effects, metropolitan municipalities CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO METEOROLOGÍA CONTAMINACIÓN ATMOSFÉRICA CONTAMINACIÓN ATMOSFÉRICA

Hot Extremes and Climatological Drought Indicators in the Transitional Semiarid-Subtropical Region of Sinaloa, Northwest Mexico

OMAR LLANES CARDENAS OSCAR GERARDO GUTIERREZ RUACHO Iván Hernández Romano ENRIQUE TROYO DIEGUEZ (2022, [Artículo])

"The main goal of this study was to explore the historical and recent spatial concurrence between the frequency (F), duration (D) and intensity (I) of hot extremes (HEs) and the frequency and evolution of meteorological drought in the region of Sinaloa. Based on the values of daily maximum temperatura (Tmax) and precipitation obtained from CLImate COMputing for the interval April–October of a historical period (1963–2000) and a recent period (1982–2014), the HE and the standardized precipitation index (SPI) were calculated on one-month (SPI-1) and four-month (SPI-4) timescales. Spearman rank correlation coefficients (Sr) were used to obtain the significant concurrences (SCs) between HEs and SPI-1, and HEs and SPI-4. El Quelite weather station showed the highest historical SCs between HEs and SPI-1 (−0.66≤Sr≤−0.57). Jaina is the only station that showed SCs with all four indicators of HEs and SPI-4 (−0.47≤Sr≤−0.34). In this study, the concurrence between HEs and SPI-1, and HEs and SPI-4 was determined for the first time. These are phenomena that can decrease the crop yield, particularly for rainfed crops such as maize, sesame and sorghum in the region commonly known as “the breadbasket of Mexico."

frequency and evolution of meteorological droughts, the breadbasket of Mexico, Sinaloa CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CLIMATOLOGÍA CLIMATOLOGÍA REGIONAL CLIMATOLOGÍA REGIONAL