Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores 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, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL

Gamma-diversity partitioning of gobiid fishes (Teleostei: Gobiidae) ensemble along of Eastern Tropical Pacific: Biological inventory, latitudinal variation and species turnover

OMAR VALENCIA MENDEZ (2018, [Artículo])

Gobies are the most diverse marine fish family. Here, we analysed the gamma-diversity (γ-diversity) partitioning of gobiid fishes to evaluate the additive and multiplicative components of α and β-diversity, species replacement and species loss and gain, at four spatial scales: sample units, ecoregions, provinces and realms. The richness of gobies from the realm Eastern Tropical Pacific (ETP) is represented by 87 species. Along latitudinal and longitudinal gradients, we found that the γ-diversity is explained by the β-diversity at both spatial scales, ecoregions and provinces. At the ecoregion scale, species are diverse in the north (Cortezian ecoregion) and south (Panama Bight ecoregion) and between insular and coastal ecoregions. At the province scale, we found that the species turnover between the warm temperate Northeast Pacific (WTNP), Tropical East Pacific (TEaP) and the Galapagos Islands (Gala) was high, and the species nestedness was low. At the ecoregion scale, historical factors, and phylogenetic factors have influenced the hotspots of gobiid fish biodiversity, particularly in the Cortezian, Panama Bight and Cocos Island ecoregions, where species turnover is high across both latitudinal and longitudinal gradients. At the provincial level, we found that the contributions of the β-diversity from north to south, in the WTNP, TEaP and Gala were high, as result of the high number of unique species. Species turnover was also high at this scale, with a low contribution from species nestedness that was probably due to the low species/gene flow within the provinces. These results highlight the importance and successful inclusion of a cryptobenthic fish component in ecological and biogeographical studies. © 2018 Valencia-Méndez 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, biodiversity, biogeographic region, biogeography, gene flow, goby fish, nonhuman, phylogeny, species distribution, species diversity, taxonomic identification, teleost, animal, animal dispersal, fish, Pacific Ocean, phylogeography, Animal Di CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE PECES Y FAUNA SILVESTRE

Evaluación de la intrusión salina utilizando el método electromagnético transitorio (TEM) y análisis de iones mayores e isótopos estables del agua en el acuífero La Misión, B.C., México

Saline intrusion assessment using transient electromagnetic method (TEM) and analysis of major ions and stable isotopes of water in La Mision aquifer, B.C., Mexico

Yesica Guadalupe Cabrera Sillas (2023, [Tesis de maestría])

El acuífero La Misión constituye una fuente importante de abastecimiento de agua en la zona semiárida de Ensenada, Baja California, México. La explotación intensiva del acuífero puede haber desarrollado el deterioro de la calidad del agua subterránea, y con ello el avance del agua de mar. El presente estudio se centra en la evaluación de la posible intrusión salina en el acuífero costero La Misión a partir de técnicas geofísicas e hidrogeoquímicas. De acuerdo con investigaciones anteriores, se plantea la hipótesis de que el acuífero está afectado por procesos de mezcla de agua de mar principalmente en la franja costera. El estudio geofísico comprende 11 sondeos Transitorios Electromagnéticos (TEM). Además, se recolectaron 18 muestras de agua subterránea en temporada de secas y lluvias, donde se analizaron isótopos estables (δ18O y δ2H) y los principales iones mayores (Na+, K+, Ca2+, Mg2+, Cl-, HCO3, CO32- y SO42-). La inversión de datos geofísicos en 1D revela dos acuíferos en la zona de estudio; 1) el acuífero de depósitos de arena aluvial saturado superficial con un rango de resistividad de 2.1-5.5 Ωm y un espesor <80 m (UH2); 2) el segundo pertenece a un acuífero semiconfinado compuesto por limolitas y areniscas con resistividades de 13.8 a 21.4 Ωm (UH4). Los resultados hidroquímicos muestran que los principales tipos de aguas subterráneas son Ca-Cl, mixtas y Na-Cl. Además, las diversas relaciones iónicas confirmaron el proceso de intercambio iónico inverso donde el Ca2+ y el Mg2+ en la matriz del acuífero se han reemplazado por Na+ en sitios favorables. El cálculo del índice de saturación de minerales indica que las muestras de agua subterránea están saturadas con respecto a los minerales de carbonato. Por lo tanto, estos resultados sugieren que el acuífero costero La Misión está sujeto a la influencia continua de la mezcla de agua de mar, disolución de minerales carbonatados ayudado por la interacción agua-roca, y los procesos de intercambio iónico. Considerando que éstos son los factores determinantes que están controlando la evolución del agua subterránea en esta zona.

The Misión aquifer is an important source of water supply in the semi-arid zone of Ensenada, Baja California, Mexico. Intensive exploitation of the aquifer may have developed groundwater quality deterioration, and the advance of seawater. The present study focuses on the evaluation of possible saline intrusion in the coastal aquifer of La Misión, using geophysical and hydrogeochemical techniques. Based on previous research, it is hypothesized that the aquifer is affected by seawater mixing processes mainly in the coastal strip. The geophysical survey comprises 11 Transient Electromagnetic soundings (TEM). In addition, a total of 18 groundwater samples were collected in dry and post rainy season, where stable isotopes (δ18O and δ2H) and the main major ions (Na+, K+, Ca2+, Mg2+, and Cl-, HCO3-, CO32- and SO42-) were analyzed. One-dimensional inversion geophysical data reveals two aquifers in the study area. 1) the shallow saturated alluvial sand deposit aquifer with a resistivity range of 2.1-5.5 Ωm and a thickness <80 m (UH2). 2) the second belongs to a semi-confined aquifer composed of siltstones and sandstones with resistivities of 13.8 to 21.4 Ωm (UH4). Hydrochemical results show that the main groundwater types are Ca-Cl, mixed and Na-Cl. In addition, the various ionic ratios confirmed the reverse ion exchange process where Ca2+ and Mg2+ in the aquifer matrix have been replaced by Na+ at favorable sites. Calculation of the mineral saturation index indicates that the groundwater samples are saturated with respect to carbonate minerals. Therefore, these results suggest that the coastal Mission aquifer is subject to the continuous influence of seawater mix, dissolution of carbonate minerals aided by water-rock interaction, and ion exchange processes. Considering these processes, the important determining factors that are controlling the evolution of groundwater in this zone.

Agua subterránea, resistividad, interacción agua-roca, índice de saturación, salinidad. Groundwater, resistivity, water-rock interaction, saturation index, salinity. CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOFÍSICA GEOMAGNETISMO Y PROSPECCIÓN MAGNÉTICA GEOMAGNETISMO Y PROSPECCIÓN MAGNÉTICA

Utilización de aguajes por el borrego cimarrón (Ovis canadensis cremnobates) y análisis de calidad del agua en Sierra Santa Isabel, Baja California, México

Watering sites use by bighorn sheep (Ovis canadensis cremnobates) and water quality analysis in Sierra Santa Isabel, Baja California, Mexico

Jonathan Gabriel Escobar Flores SERGIO ALVAREZ CARDENAS Sara Cecilia Díaz Castro Aradit Castellanos Vera Jorge Torres Rodriguez MARIANA DELGADO FERNANDEZ (2016, [Artículo])

"Se analizó la utilización de aguajes por el borrego cimarrón en la Sierra Santa Isabel, Baja California, México durante la temporada de sequía de 2011 y 2013 y el periodo de lluvias e inicio de la temporada de sequía del 2015. Asimismo, se estudió la calidad del agua, con base en siete parámetros fisicoquímicos. Se obtuvieron 260 registros fotográficos de borregos cimarrones, donde hembras, añeros y corderos representaron el 73%. En el periodo de lluvias, en dos de los aguajes se obtuvieron valores de conductividad de 1.31 µS/cm2 y 1.92 µS/cm2, y de sólidos disueltos totales de l0.65 ppt y 0.95 ppt, indicando un bajo contenido de sales en el agua. Los valores de oxígeno disuelto mayores a 6.4 ppm, dureza del agua menor a 100 ppm y PH entre 6.5 y 8.5, sugieren que el agua tiene condiciones óptimas para ser bebida por los borregos cimarrones. Los aguajes con mayor utilización por los borregos fueron El Zamora (n = 120) y El Cordero (n = 67), donde se registraron las mejores condiciones de calidad de agua en este estudio. El mayor registro de hembras y añeros, asociado a condiciones óptimas de calidad del agua, confirman la importancia de los aguajes para la crianza y reclutamiento del borrego cimarrón."

"Water used by bighorn sheep during the 2011 and 2013 dry seasons and the rainy season and drought of 2015 in the Sierra Santa Isabel of the State of Baja California, Mexico was analyzed for seven physicochemical parameters. At four watering sites, 260 photographs of sheep were obtained. Females, yearlings, and lambs accounted for 73% of the photographs. In the rainy season at two watering sites, conductivity was 1.31 µS/cm2 and 1.92 µS/cm2 and total dissolved solids was 0.65 and 0.95 ppt, indicating low salt content and safe for bighorn sheep. The watering sites with greater use by bighorn sheep were El Zamora (n = 120) and El Cordero (n = 67), which also had the best water quality. The frequent use by females and yearlings of the two sites with optimal water quality support the belief that watering sites for lambing and recruitment of bighorn sheep is important."

Baja California, borrego cimarrón, calidad del agua, cámaras trampa. Baja California, bighorn sheep, water quality, camera traps. BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) MAMÍFEROS MAMÍFEROS

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

Rapid effects of marine reserves via larval dispersal

Richard Cudney Bueno (2009, [Artículo])

Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs), with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest. © 2009 Cudney-Bueno et al.

article, environmental monitoring, fishery, larva, marine environment, marine species, Mexico, mollusc, nonhuman, oceanography, prediction, animal, biology, environmental protection, food industry, geography, growth, development and aging, larva, met CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Multiple approaches to understanding the taxonomic status of an enigmatic new scorpion species of the genus Tityus (Buthidae) from the biogeographic island of Paraje Tres Cerros (Argentina)

Andres Alejandro Ojanguren Affilastro (2017, [Artículo])

Tityus curupi n. sp., belonging to the bolivianus complex, is described from the biogeographically distinct area of Paraje Tres Cerros in north-eastern Argentina. We also present a molecular species delimitation analysis between Tityus curupi n. sp. and its sister species Tityus uruguayensis Borelli 1901 to confirm species integrity. Furthermore, a cytogenetic analysis is presented for these two species which contain different multivalent associations in meiosis, as a consequence of chromosome rearrangements, and the highest chromosome numbers in the genus. © 2017 Ojanguren-Affilastro 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.

Argentina, chromosome analysis, chromosome rearrangement, genus, human, meiosis, sister, species, anatomy and histology, animal, Argentina, chemistry, chromosome, classification, ecosystem, fluorescence in situ hybridization, genetics, geography, isl BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA DE INSECTOS (ENTOMOLOGÍA) BIOLOGÍA DE INSECTOS (ENTOMOLOGÍA)

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

Maintenance of Coastal Surface Blooms by Surface Temperature Stratification and Wind Drift

MARY CARMEN RUIZ DE LA TORRE (2013, [Artículo])

Algae blooms are an increasingly recurrent phenomenon of potentially socio-economic impact in coastal waters globally and in the coastal upwelling region off northern Baja California, Mexico. In coastal upwelling areas the diurnal wind pattern is directed towards the coast during the day. We regularly found positive Near Surface Temperature Stratification (NSTS), the resulting density stratification is expected to reduce the frictional coupling of the surface layer from deeper waters and allow for its more efficient wind transport. We propose that the net transport of the top layer of approximately 2.7 kilometers per day towards the coast helps maintain surface blooms of slow growing dinoflagellate such as Lingulodinium polyedrum. We measured: near surface stratification with a free-rising CTD profiler, trajectories of drifter buoys with attached thermographs, wind speed and direction, velocity profiles via an Acoustic Doppler Current Profiler, Chlorophyll and cell concentration from water samples and vertical migration using sediment traps. The ADCP and drifter data agree and show noticeable current shear within the first meters of the surface where temperature stratification and high cell densities of L. polyedrum were found during the day. Drifters with 1m depth drogue moved towards the shore, whereas drifters at 3 and 5 m depth showed trajectories parallel or away from shore. A small part of the surface population migrated down to the sea floor during night thus reducing horizontal dispersion. The persistent transport of the surface bloom population towards shore should help maintain the bloom in favorable environmental conditions with high nutrients, but also increasing the potential socioeconomic impact of the blooms. The coast wise transport is not limited to blooms but includes all dissolved and particulate constituents in surface waters. © 2013 Ruiz-de la Torre et al.

chlorophyll, algal bloom, article, cell count, cell density, coastal waters, controlled study, dinoflagellate, Lingulodinium polyedrum, meteorological phenomena, Mexico, near surface temperature stratification, nonhuman, nutrient concentration, popul CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA