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Interannual correlation between satellite-derived sea surface temperature (SST) and surface chlorophyll a (Chl a) are examined in the coastal upwelling zone off Punta Eugenia on the west coast of the Baja California Peninsula, area identified as intense biological productivity and oceanographic transition between mid-latitude and tropical ocean conditions. We used empirical orthogonal functions (EOF) analysis separately and jointly on the two fields from 1997 through 2007, a time period dominated by different remote forcing; ENSO conditions (weak, moderate and strong) and the largest intrusion of subarctic water reported in the last 50 yr. Coastal Upwelling Index anomalies (CUI) and the Multivariate ENSO Index (MEI) were used to identify the influence of local (wind stress) and remote (ENSO) forcing over the interannual variability of both variables. The individual EOF1 analysis showed the greater variability of SST and Chl a offshore, their corresponding amplitude time series presented the highest peaks during the intrusion of subartic water (2002?2004) and were significantly correlated with the MEI (RSST ≈ 0.68, RChl a ≈ -0.30, P < 0.001) and moderately correlated with the CUI (RSST ≈ -0.4, RChl a ≈ 0.25, P < 0.001), showing similar trends. The joint EOF1 and the SST-Chl a correlations pattern show the area where both variables covary tightly; a band near to the coast with the largest correlations (R > 0.4) mainly regulated by ENSO cycles. This was revealed when we calculate the homogeneous correlations for the periods El Niño-La Niña and the intrusion of subartic water. Both, SST and Chl a showed higher coupling and two distinct physical-biological responses; on average ENSO influence were clearly along the coast mostly in SST while the subarctic water influence, were observed offshore mostly in Chl a. We found a coastal chlorophyll bloom correlated strongly with high wind stress anomalies that reach the coast off Punta Eugenia during spring and summer 2002 and continued its presence during 2003 which showed an enrichment pattern similar to that observed at high latitudes (∼ 40° N). This observation may provide an explanation of why Punta Eugenia is one of the most important biological action centers. [ABSTRACT FROM AUTHOR]

The Gulf of Ulloa, a highly productive area off the western coast of Baja California Peninsula, is examined for five successive years (2003-2007) by using satellite data and seasonal net primary productivity estimates obtained by a vertical generalized production model. The results clearly identify a seasonal signal of coastal upwelling in productivity estimates. Highest values occur from May to June and sometimes July. We also find influence of an equatorward coastal current able of transporting water from neighboring north upwelling areas to the Gulf of Ulloa in winter-spring. This flow contributes to increase the seasonal net primary productivity. The opposite occurs in summer, when a warm poleward current of tropical characteristics arrives to the region. Our findings reveal that such warm coastal current suppressed the productivity in the whole. [ABSTRACT FROM AUTHOR]

Purpose: This paper presents a university service-learning program as an innovative model of assistance to deliver business development services to Mexican microenterprises. Design/methodology/approach: The main objectives were to deliver business development services in situ at no cost to unprivileged enterprises, conduct research on microenterprises development and build up a service-learning model of teaching and learning for students in the field of economics and surrounding disciplines. It was implemented by the Autonomous University of Baja California. It plays an important role in providing real cases and concepts on business, economics, markets and fiscal regulations. The service-learning approach prepare to students to be generous, selfless, problem solvers and job creators. Findings: The experience demonstrates that program can play a key role, both in supporting disadvantaged microenterprises and in providing meaningful learning experiences to students. The program has shown its ability to take advantage of institutional, human and financial resources already released to higher educations institutions (HEI) and government, to support social business extensively, as to make less critical the use of resources in the form of subsidies. Originality/value: This program was employed by the Mexican State Government of Baja California as a compensatory public policy against the unemployment burden created by the global crisis between 2009 and 2013. About ten thousand individuals pushed to necessity-driven entrepreneurship or informal social enterprises were assisted, trained and formalized in the tax authority by 700 university senior students. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this paper is to verify if the urban population of the municipalities of the northern border of Mexico has higher incomes than those of other municipalities in the country, while suffering worse living conditions; that is what some authors have called "border development paradox". To verify this issue, proportions were compared based on multidimensional poverty data from Coneval for the period 2008-2020, and more municipalities and population were considered than in any previous research. The results show that urban residents of the northern border have higher incomes, but also better access to services and less social deprivation. These results--which contradict some previous research, but confirm others--are maintained throughout the entire period analyzed and with different territorial groups. Therefore, it is concluded that there is no evidence of said paradox. [ABSTRACT FROM AUTHOR]

There is growing concern about the sustainability of groundwater supplies worldwide. In many regions, desalination—the conversion of saline water to freshwater— is viewed as a way to increase water supplies and reduce pressure on overdrawn aquifers. Using data from reports, articles, interviews, a survey, and a focus group, this paper examines if, and how, the adoption of desalination technology can lead to aquifer preservation in Baja California Sur (BCS), Mexico. The paper outlines existing institutional arrangements (i.e., laws, rules, norms, or organizations) surrounding desalination in BCS and concludes that there are currently no effective mechanisms to ensure aquifer preservation. Four mechanisms that could be implemented to improve groundwater management are identified, including: 1) integrated water-and land-use planning; 2) creation of an institute responsible for coordinated and consistent planning; 3) improved groundwater monitoring; and 4) implementation of water conservation measures prior to the adoption of desalination technology. This paper concludes that viewing water technologies, including desalination, as sociotechnical systems—i.e., a set of technological components that are embedded in complex social, political, and economic contexts—has the potential to create a more sustainable human–environment–technology relationship. By assessing desalination technology as a sociotechnical system, this study highlights the need to focus on institutional development and capacity building, especially within local water utilities and urban planning agencies. [ABSTRACT FROM AUTHOR]

Copyright of Western North American Naturalist is the property of Monte L. Bean Life Science Museum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Avances en Ciencias e Ingeniería is the property of Avances en Ciencias e Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Historia Mexicana is the property of El Colegio de Mexico AC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Western North American Naturalist is the property of Monte L. Bean Life Science Museum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extended Library for Visual Interactive Applications (ELVIA) is a programming tool developed and used by the two most important public universities in the Baja California peninsula in México. ELVIA provides a Java class framework that helps novice students of programming to automatically generate the graphical user interface of interactive applications, focusing in the classes and objects that compose the applications. This paper describes ELVIA, some application examples and experiences applying this programming tool in introductory programming courses. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 214-220, 2012 [ABSTRACT FROM AUTHOR]

Abstract Turtles are typically important members of Late Cretaceous vertebrate assemblages throughout North America, and are considered a useful tool to define biogeographic patterns. In Mexico, Cretaceous turtles have been recorded in the states of Baja California, Chiapas, Chihuahua, Coahuila, Nuevo León, Puebla, and Sonora; specifically the state of Coahuila shows so far, the highest diversity of turtles. In this paper, the diversity of Late Cretaceous turtles from the El Gallo Formation (Baja California) is reviewed. Previously, only Naomichelys speciosa was recognized in this Formation. Based on fragments with distinctive sculpture patterns four additional taxa are recognized, Compsemys victa , Basilemys sp., Trionychidae indet., and cf. Chelydridae. With the recognition of these new taxa, the knowledge of Cretaceous turtles diversity of the El Gallo Formation is increased. This assemblage is unusual compared to other North American turtle assemblages because it suggests the presence of previously unrecognized biogeographic patterns. Here we report the first record of Basilemys sp. from the Late Cretaceous of Mexico and the presence of cf. Chelydridae on the western side of Laramidia. Highlights • Assemblages of fossil turtles of the Late Cretaceous of El Gallo Formation. • New occurrences of turtles are reported from El Gallo Formation. • Turtles from El Gallo Formation provide information on the western side of Laramidia. • Mexico has the southern-most Cretaceous localities in North America. • Reported the first record of Basilemys sp. in the Late Cretaceous of Mexico. [ABSTRACT FROM AUTHOR]

Might a cosmopolitan identity emerge as the logical cultural response to mundialization and economic globalization? With this question in mind I conducted in-depth interviews with 20 young people between the ages of 16 and 29 in Tijuana during 2004. This paper is the result of an analysis of their discourse on the phenomenon generically described as globalization. I present here the varied reactions of young Tijuana residents to what it means to be young, a border dweller, Mexican, and tijuanense and the ways they characterize members of 'other' cultures with whom they share metropolitan Tijuana. [ABSTRACT FROM AUTHOR]

For the prestigious Mexican historian, Miguel León-Portilla, the Yumans of Baja California were not Indians of warfare, but rather Indians of peace. In the opinion of this researcher, it was because lived in the fossilized-paleolithic stage that these Indigenous groups did not present any kind of resistance against the European colonization, making possible their easy domination and posterior diminishment or assimilation. This paper questions these advancements not only because of their lack of technical precision, but also because they obscure the role of agency that these Indians played during the missionary period. On the contrary, this paper endorses Edward Spicer's (1962) assertion that resistance was present even among those groups that were not seriously engaged in significant fights against the Spanish conquerors. In the particular case of the Yuman people, this is a resistance challenging the Pueblo Indio project and its related implications in terms of sedentary lifestyle, agricultural economy and the adoption of a scheme of central authority. As we know, these patterns were opposed to those observed among the Yumans as nomads, hunters and gatherers, organized into a segmentary lineage system. Moreover, the kind of resistance described in this paper constitutes what James C. Scott (1990) refers to as the hidden and daily life transcripts, such as ingenuity, intelligence simulating ignorance, and irony, as well as, those economic and social practices studied by Jan Rus (1995), which include mobility and appropriation of the missionary site, all with the intention of perpetuating the presence of these Indigenous people and make possible their social reproduction. [ABSTRACT FROM AUTHOR]

For the prestigious Mexican historian, Miguel León-Portilla, the Yumans of Baja California were not Indians of warfare, but rather Indians of peace. In the opinion of this researcher, it was because of their living in a fossilized paleolithic state that these Indigenous groups did not present any kind of resistance against the European colonization, making possible their easy domination and afterwards diminishment or assimilation. This paper questions these assertions not only because of their lack of technical precision, but also because they obscure the role of agency that these Indians played during the missionary period. On the contrary, this paper endorses Edward Spicer (1962) in the sense that resistance took place even among those groups who were not seriously engaged in significant fights against the Spanish conquerors. In the particular case of the Yuman people, this resistance challenged the Pueblo Indio project and its related implications in terms of sedentary lifestyle, agricultural economy and the adoption of a scheme of central authority. As we know, these patterns were opposed to those observed among the Yumans as nomads, hunters and gatherers, organized into a segmentary lineage system. Moreover, the kind of resistance described in this paper constitutes what James C. Scott (1990) refers to as the hidden and daily life transcripts, such as ingenuity, intelligence simulating ignorance, and irony, as well as those economic and social practices studied by Jan Rus (1995), which include mobility and appropriation of the missionary site. All of these acts had the intention of perpetuating the presence of these indigenous people and make possible their social reproduction. [ABSTRACT FROM AUTHOR]

For many years, the Food and Agriculture Organization of the United Nations (FAO) has insisted on the importance of biodiversity conservation. Agriculture and livestock breeding were the first sectors to understand the importance of conservation. Although the fishing sector has fallen behind, several countries have developed programs to preserve aquatic genetic resources. In Mexico, the National Science and Technology Council (CONACyT) and Secretary of Environment and Natural Resources (SEMARNAT) are supporting a pilot project to help in the conservation of aquatic species. This project focuses on the development of the Germplasm Bank of Aquatic Species of Baja California (GBAS). One of the most crucial parts of any germplasm repository is the information system supporting the operation of the bank. The development of a management information system depends on the objectives of the repository. The process requires planning, taking into account the particular design needed for the bank and identification of functions. The goal of this work was to describe the development of the information system designed for the GBAS. The operational requirements characterized for the information system was called GBAS Information Management System (GBAS-IMS® and include requirements for managing the information of the bank and a set of requirements for the protocol definition such as the user management, the facility management, and the information publication over the Internet. Due to the complexity defined by the set of requirements, the use of information technologies was required to guarantee a functional and reliable system. This paper describes how the use of information technologies together with a set of software engineering practices allowed the construction of the information system. The items described on it includes the development process to build the system, the architecture defined for the system, a description of the most important components, the database schema defined for the system, the most relevant information about the implementation, and experiences and future work. [ABSTRACT FROM AUTHOR]

This paper explores resident attitudes to volunteer tourism in several small communities within Tijuana, Mexico. Social exchange theory has been used to argue that the degree of personal benefit from volunteer tourism would predict residents' perceptions of the impacts of volunteer tourism and support for volunteer tourism planning and for volunteer tourism activities. Survey research of a purposive sample targeted several neighborhoods within Tijuana that were extensively "voluntoured". Results indicate mixed support for social exchange theory. Implications are discussed concerning the need for volunteer tourism organizations to include a variety of community stakeholders in the volunteer tourism development process. [ABSTRACT FROM AUTHOR]

The production of culture in urban image-making has received much attention within geography. This paper intervenes in the culture-economy debates in a slightly different way - namely, through the lens of an understudied city of the global South. It examines the structure and discourses embedded in the Tijuana (Mexico) Municipal Plan 2005-07 to interrogate the work that culture performs with an eye to the impacts (both material and discursive) of official strategies across time and space. In so doing, two propositions are suggested. First, post-colonial spaces offer important sites from which to critique the conflation of cultural practice and policy. Secondly, the complex imbrication of culture and economy can be further distilled in grounding examples in ordinary cities. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to use the experience of pollution in the Imperial and Baja California Valleys under NAFTA, as a cautionary model to provide recommendations for deterrence of similar ecological degradation effects that could emerge under the newly-approved CAFTA. Design/methodology/approach - Analysis of the region using existing statistical data and content analysis of qualitative data from the Imperial and Baja California Valleys, and Costa Rica. Findings - Economics and ecology have thus far not proved to have a complementary relationship, based on the NAFTA experience in the Imperial and Baja California Valleys. Early data on environmental law suits in the CAFTA region against environmental regulations also point to a negative attitude by business to environmental protections of nation-states. CAFTA's investment rules puts corporate rights over ecosystems by limiting public regulation and granting legal avenues to corporations to sue governments for "barriers to trade", where national environmental laws are seen as these so-called "barriers to trade". Research limitations/implications - CAFTA was promulgated in 2005, but only put into effect, January 1, 2006. Thus, as more data emerges about its impacts, additional and more definitive studies can be undertaken. Practical implications - Looking at the possible environmental effects of CAFTA and NAFTA provides the international community a chance to consider early remediation and prevention measures for the environmental sustainability of the CAFTA region within the context of this large economic market. Originality/value - This is a fresh and early look at a newly-installed international trade policy, and its value to scholars and practitioners lies in its cautionary guidance for the future of CAFTA. These arguments are based on experience with other, more longer-lived, trade policies like NAFTA. [ABSTRACT FROM AUTHOR]

This paper presents an observational analysis of tropical cyclone landfall over the eastern Pacific Ocean. The tropical cyclone that developed during the 2001 season off the Mexican coast was named Juliette and made landfall in the Baja California peninsula. Juliette approached land over the southwestern peninsula, and the evolution of a localized region of cyclonic circulation occurred over the Gulf of California. The storm passage was associated with extensive property damage to the population in the southern peninsula, with most of the damage caused by heavy rainfall and strong winds. The intensity of the circulation associated with Juliette indicates that this was a strong system in the record of landfall during the period 1992–2002. All available sources of observations are collected to investigate characteristics of the circulation motion and structure. In situ observations, including surface and upper-air data, are applied to document the evolution of storm flow while the center was located near and over the southern peninsula. Imagery from a geostationary satellite is used to determine characteristics of convective patterns. The analysis indicates development of distinct bands of deep convection and a period of slow system motion, which are related to large precipitation. Low-level winds are used to identify characteristics of the incident circulation along the Pacific coast. However, the nocturnal nature of the event and the lack of observations at critical times limit the attempts to explain how the incident circulation is associated with that observed over the gulf the next morning. [ABSTRACT FROM AUTHOR]

We analysed the floristic turnover, or β-diversity patterns, of woody legumes in Baja California, the 1300 km long peninsula in NW Mexico. From the specimen labels of nine herbaria, we digitized 4205 records from 78 species and projected them onto a grid of 205 cartographic cells (20 longitude&tims; 15' latitude). We found that the E-W turnover from the Pacific coast to the Sea of Cortés was high (ca, 60% change from one cell to the next) and that it was significantly associated with topographic variation across the peninsula. An analysis of between-site similarities showed that floristic regions in the peninsula have well defined boundaries, and that floristic similarities tend to extend for long distances along the coastal corridor of the Sea of Cortés, Finally, a numerical classification of Baja California based on the floristic attributes of the cells separated the peninsula into five well defined regions that coincide very closely with regionalizations, previously proposed by various authors using descriptive methods, and with the areas of endemism described for the peninsula in a previous paper. We conclude that the ecological regions of woody legumes in the peninsula clearly reflect the two main environmental forces that act on it, namely, the 1300 km long temperate-tropical climatic gradient and the dramatic E-W gradient running from the Pacific Ocean ca, 100 km across the mountain range into the Sea of Cortés. [ABSTRACT FROM AUTHOR]

The San Antonio-El Triunfo mining district, located at a mountainous region 45 km south-east of La Paz, Baja California, has been worked since the late 1700s. Mine waste material produced during 200 years of mineral extraction area poses a risk of local groundwater pollution and eventually, regional pollution to the Carrizal (west basin) and the Los Planes (east basin) aquifers. There are different types of deposits in the mining area. These are dominated by epithermal veins, in which arsenopyrite is an important component. Carrillo and Drever (1998a) concluded that, even though the amount of mine waste is relatively small in comparison to the large scale area, significant As in groundwater derived from the mine waste piles is found locally in the groundwater. This paper shows the results of geochemical analyses of groundwater samples from the San Antonio-El Triunfo area and the Carrizal and Los Planes aquifers during several years of monitoring (1993–1997). The highest values of total dissolved solids (TDS) and As are in the mineralized area where the mining operations occurred (∼1500 ppm TDS and 0.41 ppm As). The lowest concentrations of TDS and As are, in general, away from the mineralized area (∼500 ppm TDS and 0.01 ppm As). Sulfate and bicarbonate (alkalinity) are, in general, high near the mineralized area and low away from it. The arsenic concentrations vary seasonally, especially after the heavy summer thunderstorms. Geochemical modeling (MINTEQA2 and NETPATH) and analysis of the regional geochemical evolution of the groundwater from the mining area towards the aquifer of Los Planes shows that the most likely hydrochemical processes include: dilution, precipitation of calcite, and adsorption of As onto surfaces of iron oxyhydroxides (ferrihydrite). These processes act as natural controls to the extent and amount of As pollution in the Carrizal and Los Planes aquifers. [ABSTRACT FROM AUTHOR]

Abstract The genus Nolina on the Baja California peninsula has not been critically studied. Most of the taxonomic literature dealing with this group is older or incomplete in nature. Taxonomic problems with this genus arise because it is not easy to make herbarium specimens from plants in the field and the taxa are not well represented in collections. Species in this genus are difficult because they are dioecious, generally have large rosettes with many leaves, leaf margins that often cut skin, and the plants have large inflorescences. On older herbarium specimens, it is common to find only a leaf and an inflorescence fragment, and labels often do not provide taxonomically important information such as the plant's growth habit type. Consequently, distinctive inflorescence characters are usually missing from the specimen or from the label data. It is rare to find a complete specimen collection that includes all of the needed species-relevant data. Decisions for delimiting species in this genus are not easy, and in this case, were based mostly upon their morphological character consistency, geographic distribution, and environmental factors. Five species of Nolina are now registered for the Baja California peninsula: N. beldingii, N. bigelovii, N. interrata, N. palmeri, and the new nomenclatural combination N. brandegeei (Trelease) L. Hern. This paper includes: a species identification key, species taxonomic descriptions, ecological and geographical information, common names, taxonomic discussions of species, and pictures for species recognition of all taxa in the Baja California region. [ABSTRACT FROM AUTHOR]

A succession of interannual warm events occurred in the Pacific during the 2013-2016 period, when positive thermal anomalies were detected. A broad region with abnormally warm waters in the northeastern Pacific Ocean was observed in 2013, which by 2015 had reached waters off Baja California (Mexico). In addition to the ongoing warming effect, early evidence of an El Niño event was detected in 2015. This paper analyzes hydrographic data measured at Todos Santos Bay and environs, as well as satellite-derived sea-level data, to characterize changes in the hydrographic conditions during the 2013-2016 period. The highest positive temperature anomalies (~5 °C) were observed in September 2015, with a steep decline to neutral conditions in spring 2016. Records for the bay showed slight variations in hydrographic conditions during spring, highlighting the importance of local over remote forcings during this time of year. In autumn, by contrast, interannual signals prevailed over local processes. Satellite-derived sea-level data revealed an alongshore propagation of remote signals, identified as shallow coastal poleward flows. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Sociedad Entomológica Argentina is the property of Sociedad Entomologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper examines the persistent histories and lasting effects of the Baja California peninsula's status as an "almost island". The peninsula is almost an island in so many ways. Its reputation as an island-like entity has also been strengthened by a longstanding myth that it was, in fact, an actual island. In many senses it was an island-- isolated, remote, difficult to envision, understand, and control. Geography and climate played a vital role in all of this, but so, too, did human imagination. The author uses the concept of shima, along with discussions about the dual meanings of the Spanish word aislamiento as a way to explore these issues. Aislamiento can refer more concretely to the effects of being on a landform surrounded by water, on the one hand, or the deep social and psychological effects of isolation. Ultimately, the author argues that it is this sense of isolation that works to produce, regardless of geographic and cartographic reality, a powerful sense of islandness. [ABSTRACT FROM AUTHOR]

Pisonia is a primarily American genus, distributed mainly in subtropical to tropical regions. In this paper a new species, Pisonia calafia, is described and documented. This species occurs as a small population on a coastal strand in the Cape Region of the Baja California Peninsula. The main characteristics that differentiate P. calafia from the rest of Pisonia is the lack of sulci and glands in the fruit. In addition to the new species description, we discuss the evolutionary affinities of this new taxon based on phylogenetic analysis of nrITS sequence data. The known population is limited to a few dozen individuals, now seriously endangered by the ongoing development of tourism projects. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Between July of 1891 and May 1892, the Mexican Land and Colonization Company, a British enterprise with a concession over the major part of Baja California's wastelands, laid 27 kilometers of rail of what was to be known as the Peninsular Railway with the expectation of opening up lands to cultivation and settlement, and attracting investment. But the train's starting point was San Quintin, a shallow bay ill-suited to becoming an important shipping port and, as far as the tracks had been built, led to nowhere. However, the objective of this paper is not to analyze the reasons for which the railway project did not come to a happy termination. Rather, it focuses on the controversies and conspiracies which surrounded its construction, arising from the struggle between the United States and Great Britain for predominance in Mexico's far northwest. [ABSTRACT FROM AUTHOR]

This article analyzes the importance of an approach on local environmental management regarding the quality of air in the Mexicali and Imperial Valley region. The paper discusses that the absence of a strategic approach in the environmental local policy will enhance the air pollution in the region. [ABSTRACT FROM AUTHOR]

The everyday lives of youth sex workers remain largely ignored in global debates about the impact of criminalization and policing on sex workers. Youth sex workers are often portrayed as victims of commercial child sexual exploitation, with little acknowledgement of their everyday worlds. Using data from a mixed method study with youth and adult sex workers in Tijuana, this paper will explore the occupational experiences of youth sex workers within a social context where many adult sex workers have obtained a quasi-legal status, as well as the consequences of age status with respect to occupational risks and hazards. [ABSTRACT FROM AUTHOR]

Abstract: Because of its long-lived (Late Miocene to Pleistocene) post-subduction volcanic activity and location, the San Borja volcanic field (SBVF) is a key area for understanding the physical mechanisms controlling the spatial distribution of post-subduction volcanism on the Peninsula of Baja California. In this paper, we study the distribution and general characteristics of individual eruptive centers in the SBVF, aiming to provide insight into the changing physical nature of post-subduction magmatism and the control on vent location in a very unique tectonic setting. Volcanic activity has built more than 227 high-magnesium andesites (HMA) monogenetic scoria cones and thick lava flows capping large mesas during the last 12.5Ma. The average (mean) eruptive center in the SBVF has a height of 85m, a basal diameter of 452m and a slope angle of 30°. Our volcanic alignment analysis of this field is based on field data, satellite images, and a quantitative method for detecting volcanic center alignments. The morphologic data, together with new 40Ar/39Ar geochronology data have been used to refine our alignment analysis and to better delineate the temporal evolution of post-subduction volcanic activity in this field. The available ages vary from 3.53±0.18 to 10±0.23Ma suggesting that the long-lived HMA volcanism occurred almost continuously (with some concentration of pulses) throughout Late Miocene and extending to the Pleistocene and even into the Quaternary, replacing the arc-related activity of the Comondú arc which vanished in this area around 12.5Ma. Alignment analysis confirms a NW–SE direction as the preferred orientation of volcanic alignments and shows that vent elongations do not display a strong parallelism in any particular direction, marking the absence of matches between lineaments defined by multiple vents and orientations of vent elongation. The results of the volcanic alignment analysis allowed us to infer the direction of the maximum instantaneous extension (S 1_local) at SBVF from Late Miocene to Quaternary. We compared this value to the direction of maximum instantaneous extension for the Baja California Peninsula at a regional scale (S 1_regional), which can be estimated from regional tectonic reconstruction. The comparison of S 1_regional and S 1_local allows us to quantify the influence of tectonic stresses in controlling the localization of monogenetic volcanism at the SBVF. [Copyright &y& Elsevier]

Constraining the origin of the adakite--high-Nb basalt (HNB) association in Baja California, Mexico, is critical to a better understanding of global arc magmatism. Currently the preferred explanation for the close spatial and temporal association of the two rock suites is through melting of the basaltic portion of the subducted Farallon-Cocos plate, thus providing support for the slab-melting origin of adakites elsewhere. Moreover, a tectono-magmatic model involving the production of both adakite and HNB from slab melts offers a comprehensive explanation for the origin of the atypical, arc-related, postsubduction magmatism in Baja California. This paper proposes alternative models for the origin of HNB and postsubduction magmatism in Baja California, wherein the unusual geologic setting of western Mexico and westward movement of North America permitted the influx of Pacific asthenosphere beneath the adjacent Gulf of California after the cessation of subduction. Unlike the previous tectono-magmatic model, the new models propose that the asthenosphere provided a direct source for postsubduction tholeiitic and rare alkali magmas that were erupted in Baja California as tholeiites and HNB, respectively. Fractional crystallization of some of the HNB magmas plus assimilation of tholeiitic materials produced Nb-enriched basalts (NEB). The influx of Pacific asthenosphere after the cessation of subduction also provided thermal energy to melt the mafic lower Baja California crust, producing adakite rocks, and the preexisting metasomatized mantle wedge, producing bajaites and calc-alkaline magmas. [ABSTRACT FROM AUTHOR]

Abstract: Data from distribution, ecology, and stomach contents of four desert shrews, Notiosorex crawfordi (Coues), collected from a large gap in their known distribution on the Baja California peninsula, in Mexico is presented in this paper. The contents in the stomach were specimens of the order Araneae, Hymenoptera, Coleoptera, Dictioptera, and Acari, and small quantities of plant material were also found. [Copyright &y& Elsevier]

This paper describes diversity patterns of the polychaete fauna in Bahía Todos Santos (Pacific Ocean, Baja California, Mexico). Thirty-nine stations were sampled in October 1994. Measurements of depth, temperature, salinity, dissolved oxygen, organic content and sediment particle size were made. Polychaetes constituted 64% of all invertebrate macrofauna, with 13,757 specimens in 44 families representing 203 species. The best represented families were Spionidae, Capitellidae, Paraonidae, Cirratulidae, Maldanidae, Ampharetidae and Nephtyidae. Bahía Todos Santos presented high species richness (species/station); values varied between 6 (near the harbor) and 67 species (next to Estero Punta Banda). Higher species richness values (48 species to 67/station) were located in the southern section of the bay. Abundances (individuals/station) were generally high (120–1434) except for some coastal stations. Nearly one-third of the stations presented H′ values higher than 4.00. Diversity (H′) values ranged from 2.06 to 4.80; higher diversity values were found in the southern section of the bay.The stress-predictability modeling characterized approximately 70% of stations as presenting favorable and stable conditions. Pearson and Bray–Curtis coefficients separated stations in relation to their sediment particle size, depth and location in the bay. Principal component analysis determined that organic matter content, percentage of silt-clay, and water depth accounted for 95% of the total variance for all environmental factors measured. Correspondence analysis distinguished three groups of species: Group A species with an extensive distribution throughout the bay and relatively high abundances, Group B species abundant in the shallow areas, especially near the harbor, and Group C species present in the area of the submarine canyon. Non-metric multidimensional scaling analysis separated five groups of stations, depending on depth, grain size and location in the bay. Our results show that Bahía Todos Santos is a favorable environment for polychaete development, their distribution being strongly related to sediment characteristics. The dominant trophic group corresponds to deposit-feeders (91 species). [Copyright &y& Elsevier]

The exceptional growth of whalewatching in Baja California Sur (BCS) and other parts of Mexico during the last 10 years motivated the design and implementation of a Mexican whalewatching law based on experiences in BCS. However, recent research in the Ensenada whalewatching area confirms that this law is insufficient in this area because whalewatching boats and other fishing, cruising, or drifting boats influence the behavior (swimming direction and velocity) of migrating gray whales. In the long term, the migration corridor might be displaced offshore, and whalewatching may become infeasible. This study proposes a management planning process to adapt regulations to this area, to promote adherence to regulations by encouraging selfregulation and strengthening law enforcement, and to enhance the tourist service on board. The actors involved were identified. [ABSTRACT FROM AUTHOR]

This paper examines the oceanic response off Baja California, Mexico, to the 1997–1998 El Nin˜o and the transition to La Nin˜a conditions. The data presented were gathered during seven cruises over a grid based on the CalCOFI station plan, from lines 100–130, out to station 80. T–S diagrams with data obtained during the peak phase of El Nin˜o, demonstrate that warmer and saltier (spicier) than normal conditions prevailed in the upper 600 m over this region. Temperature and salinity anomalies calculated for CalCOFI line 120 revealed waters near the coast at 50 m depth to be up to 8.7 °C warmer and S=0.8 saltier than the climatology during October 1997. These large anomalies persisted through January 1998, with some slight diminution in the magnitudes near the surface. This study suggests that anomalously warm and salty waters were fed from a source of spicy water to the southwest, identified as Subtropical Surface Water (StSW), and that low-salinity Tropical surface waters (TSW) were blocked to the southeast in the vicinity of the tip of the Peninsula. Subsurface waters associated with the California undercurrent (CU), fed from the Eastern Tropical Pacific (ETP), were also warmer and saltier than normal, and indicate a significant expansion in volume of the CU, presumably a result of intensification of poleward flow at depth. We postulate that the well defined near-surface and deep poleward flows in the study area reflect anomalous large-scale cyclonic circulation affecting the flow in the southeastern region of the North Pacific subtropical gyre east of 125°W. Following the El Nin˜o event, warm and salty upper waters retreated to latitudes south of Punta Eugenia. With the return to normal and cooler conditions, equatorward flow over the sampling grid predominated with an increased meandering and mesoscale activity. Transition to La Nin˜a conditions would have been associated with re-establishment of normal anticyclonic flow in the southeastern quadrant of the Pacific subtropical gyre. [Copyright &y& Elsevier]

Off-shore assembly plant operations have become an increasingly important source of jobs and foreign exchange for some developing countries. This paper, using cross-section data of individual assembly plants in Baja California, examines factor substitution and adaptation taking place in this labor-intensive type of operation. For contrast the technologically advanced electronic industry and the more traditional apparel assembly industry are compared. A two level CES production function which treats skilled labor as a separate factor of production is used to estimate elasticities of substitution. The study found evidence of factor adaptation occurring. Estimates of elasticities of substitution, while refuting the hypothesis of zero elasticity, are generally inelastic. This suggests that policies affecting wages of unskilled labor relative to skilled labor and capital can increase employment, but would decrease unskilled labor's total share of income. [ABSTRACT FROM AUTHOR]

In this work, we report new chemical and isotopic data (3He/4He, δ13CCO2, δ13CCH4, and δDCH4) from poorly or previously unstudied hydrothermal and magmatic gases that are emitted along the eastern coast of the Baja California Peninsula (BCP). High 3He/4He values (up to ~7 Ra) characterize the magmatic gases, while lower ratios (≤1.6 Ra) characterize hydrothermal springs. We infer that the mantle beneath the BCP could be Mid‐ocean‐ridge basalt (MORB)‐likes, as in the rift within the Gulf of California, or it may reflect contamination from C‐rich sediment during paleo‐subduction of the Farallon plate. During their ascent, through the crust, mantle/magmatic gases mix with CO2‐ and 4He‐rich fluids, thus forming CO2‐rich hydrothermal gases. These hydrothermal gases undergo partial dissolution of CO2 in shallow waters under different temperature and pH conditions, which further modifies their composition. Thermogenic and possibly abiogenic sources of methane are present only in magmatic gases from the BCP. Secondary methane oxidation (microbial/inorganic) processes are proposed for some hydrothermal gases, which are extremely enriched in heavy isotopes. Finally, we argue that the hydrothermal gases that are emitted from the BCP have variable percentages of mantle contribution, indicating the presence of lithospheric faults enhancing the rise of mantle fluids also in areas where volcanism is absent. Key Points: Based on 3He/4He, the gases emitted from the Baja California Peninsula have two origins: magmatic and hydrothermalThe hydrothermal gases contain variable mantle contributions that indicate the presence of active faultsThe mantle beneath the Baja California Peninsula could be contaminated from subducted C‐rich sediment [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mammalogy is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Six amphidromous species of Macrobrachium Spence Bate, 1868 have been recorded on the Pacific slope of Mexico, including the two morphologically related M. hobbsi Nates & Villalobos in Villalobos Hiriart & Nates Rodríguez, 1990 and the Atlantic species M. olfersii (Wiegmann, 1836). The hypothesis that the formation of the Isthmus of Panama in the Late Pliocene produced a vicariant event leading to the formation of two groups of Macrobrachium species, one on the Atlantic slope and the other on the Pacific slope, has raised doubts about the amphiamerican occurrence of M. hobbsi and M. olfersii. Recent molecular studies have supported that hypothesis that there are no amphiamerican species of Macrobrachium, but rather amphiamerican species groups. In a previous publication, we proposed that one of the groups occurring along the Mexican slopes is the olfersii group, comprising the digueti subgroup, and the olfersii subgroup represented by M. hobbsi in the Pacific and M. olfersii in the Atlantic. We reviewed the systematics of the olfersii subgroup from the Pacific slope by analyzing individuals obtained from 104 sites in 44 drainage basins in nine Mexican states. Morphological and molecular genetic analyses with newly generated fragments of the mitochondrial genes 16S (470 bp) and COI (542 bp) confirm that, in the olfersii subgroup, only one morphologically plastic species, M. hobbsi, occurs on the Mexican Pacific slope. It is the most common species of Macrobrachium on this slope and is genetically different from the M. olfersii Atlantic populations. The results also indicate that disjunct populations of the Baja California Peninsula and the mainland belong to the same genetic lineage. [ABSTRACT FROM AUTHOR]

Evaluating historical changes in the exploitation of marine organisms is a key challenge in fisheries ecology and marine conservation. In the Eastern Pacific, marine turtles were exploited for millennia before systematic monitoring began <50 years ago. Using ethnographic and historical data, we generated a detailed reconstruction of the East Pacific green sea turtle ( Chelonia mydas) fishery in Mexico's Baja California peninsula from 1700 to 1990. Sea turtles from the region's important feeding areas were a staple food source from the earliest phases of human occupation, dating back at least 12,000 years. In contrast with regions such as the Caribbean, small human populations and limited market access resulted in apparently sustainable turtle harvests until the second half of the 20th century. We found that the estimated annual catches between 1960 and 1980 exceeded the estimated annual catches of the previous 250 years by an order of magnitude, leading to the collapse of the fishery and the depletion of the green turtle population. A total ban on sea turtle captures in 1990, comprehensive nesting beach protection, and significant conservation efforts resulted in increases in breeding females on nesting beaches and catch rates in scientific monitoring on main feeding grounds since the early 2000s. This provides a positive outlook for this once-depleted population segment. Although further research is needed to evaluate current conservation status, we have identified a date, between 1950 and 1960, which can serve as a reliable temporal reference for future evaluations of historical baseline abundance in this region. [ABSTRACT FROM AUTHOR]

The complex geological and ecological processes that have generated high levels of biodiversity and endemism in the Baja California Peninsula have been the subject of intensive study. However, relatively little is known about phylogeography of the iconic endemic palm species of this region. We therefore analyzed a total of 2,294 bp of chloroplast and 738 bp of nuclear sequence data in 169 samples of five native palm species from Baja California, Sonora and Guadalupe Island. We found that Washingtonia and Brahea palms had low levels of genetic diversity and were highly structured, with the majority of species and major geographic regions being characterized by distinct haplotypes. We also found strong support for currently recognized species in Washingtonia, but our results were less clear cut for Brahea due to haplotype sharing. Furthermore, patterns of population structure were broadly consistent with historical vicariant events such as the inundation of the Isthmus of La Paz, the formation of the Sea of Cortez, and the more recent colonization and isolation of Guadalupe Island's palms. Our findings contribute toward a growing appreciation of the complexity of plant responses to past geological changes and also provide valuable baseline genetic data on relict American palm species. [ABSTRACT FROM AUTHOR]

The current distribution and genetic relationships among populations of jackrabbits of the genus Lepus in the Baja California Peninsula and adjacent islands resulted from climate warming and rising sea levels following the Last Glacial Maximum, ~21 000 years BP. The colour pattern of the pelage and the genetic, biogeographic, and taxonomic relationships among peninsular and insular jackrabbit populations were investigated using four mitochondrial DNA genes (Cyt b, DLoop, COI, and COIII) and one nuclear gene (β-fib I7). The phylogenetic analyses identified two clades, one of them with three well-supported subclades that corresponded to three geographical groups within the Baja California Peninsula (including insular populations), with a slight genetic differentiation between these subclades (average of 0.5%). The second clade corresponded to a group outside the Baja California Peninsula. Insular populations appear to have been isolated within the last 5000 years. We recommend dividing L. californicus in the Baja California Peninsula and adjacent islands into four groups at subspecific level. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coastal habitats are crucial to pinnipeds for resting, molting, and reproduction. We examined terrestrial habitat preferences of four pinniped species (California sea lion, Guadalupe fur seal, harbor seal, and northern elephant seal) on the islands off the western coast of the Baja California Peninsula, Mexico. Boat-based surveys were conducted while circumnavigating 10 islands or archipelagos during summer and winter in 2009 and 2010. Habitat selection was inferred based on generalized linear models using animal counts and four habitat descriptors (substrate type, tide pools, bathymetry, and surf protection). The interspecific overlapping was analyzed using the Morisita index. Sea lions, fur seals, and harbor seals used sheltered beaches and rocky platforms as breeding sites. Cobblestone and sandy beaches were the most important substrates for elephant seals. Cliffs were the least preferred habitat by all species. Although substrate preferences were similar among species, segregation was observed in most islands except at the San Benito Archipelago, where sea lions co-inhabit with elephant seals and fur seals. In the context of a recolonization process, these results could provide insights about the location of future colonies and information on habitat use, which can be used when designing conservation strategies for the islands. [ABSTRACT FROM AUTHOR]