Northwest Yucatan Research Articles

Wind energy potential assessment for Mexico's Yucatecan Shelf

The objective of significantly decreasing the use of fossil fuels due to their environmental impact has led to rethinking strategies to satisfy the global energy demand. Thus, the study and understanding of renewable energy resources is of great importance. Due to the maturity of the technology, wind is currently one of the most competitive sources of renewable energy, and development has focused on making wind power production more efficient, particularly in regions with great potential. The Yucatan Peninsula, Mexico, is one of these regions where inland commercial wind farms are already operating. However, these projects have caused environmental and social problems. Therefore, here we propose the development of offshore wind as an alternative. This study aims to calculate the offshore wind potential on the northern Yucatan Peninsula and its continental shelf, to outline/study a design of an offshore wind farm on a selected location at/on the northwest Yucatan coast. WRF atmospheric model data from 2005 to 2016 were used. The numerical simulations were validated with measured data from meteorological stations in the region, both inland and offshore. Characterization of the wind field at different temporal scales was performed, and subsequently, the wind potential was analyzed. The offshore zone with the highest potential was delimited, and a wind farm outline was proposed. The offshore wind farm potential was estimated, showing to be within an ideal range to reach a maximum power level. Besides having a significant wind potential, this zone provides additional advantages, such as mild wave conditions and a shallow depth far from the coast.

MIDDLE PRECLASSIC POTTERY PRODUCTION AND EXCHANGE IN THE NORTHERN MAYA LOWLANDS: AN ICP-MS ANALYSIS

AbstractEvidence of complex and widespread occupations during the Middle Preclassic (1000–350 b.c.) have been identified throughout the Northern Maya Lowlands and are associated with both Mamom and pre-Mamom ceramics. Beyond typological information based on the visual examination of paste, slip, and surface treatment, archaeologists know little about the technology or economics of pottery production and exchange of this period. In this study, we analyze Middle Preclassic ceramics from four sites in northwest Yucatan, using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to determine the chemical variation that exists between and within different ceramic production areas. The analysis indicates that production occurred locally by the late Middle Preclassic (700–350 b.c.), and that the earliest pottery produced in the Northern Maya Lowlands, at the sites of Komchen and Kiuic, was compositionally linked to later phases of production. This means that the first ceramic complexes of the Northern Lowlands were locally produced and not the result of migrants bringing pottery from elsewhere. The study reveals it is possible to identify the origin of Middle Preclassic ceramics by their chemical signature and that compositional variation existed at the site level over time.

Late Holocene environmental change in Celestun Lagoon, Yucatan, Mexico

Epikarst estuary response to hydroclimate change remains poorly understood, despite the well-studied link between climate and karst groundwater aquifers. The influence of sea-level rise and coastal geomorphic change on these estuaries obscures climate signals, thus requiring careful development of paleoenvironmental histories to interpret the paleoclimate archives. We used foraminifera assemblages, carbon stable isotope ratios (δ13C) and carbon:nitrogen (C:N) mass ratios of organic matter in sediment cores to infer environmental changes over the past 5300 years in Celestun Lagoon, Yucatan, Mexico. Specimens (> 125 µm) from modern core top sediments revealed three assemblages: (1) a brackish mangrove assemblage of agglutinated Miliammina and Ammotium taxa and hyaline Haynesina (2) an inner-shelf marine assemblage of Bolivina, Hanzawaia, and Rosalina, and (3) a brackish assemblage dominated by Ammonia and Elphidium. Assemblages changed along the lagoon channel in response to changes in salinity and vegetation, i.e. seagrass and mangrove. In addition to these three foraminifera assemblages, lagoon sediments deposited since 5300 cal yr BP are comprised of two more assemblages, defined by Archaias and Laevipeneroplis, which indicate marine Thalassia seagrasses, and Trichohyalus, which indicates restricted inland mangrove ponds. Our data suggest that Celestun Lagoon displayed four phases of development: (1) an inland mangrove pond (5300 BP) (2) a shallow unprotected coastline with marine seagrass and barrier island initiation (4900 BP) (3) a protected brackish lagoon (3000 BP), and (4) a protected lagoon surrounded by mangroves (1700 BP). Stratigraphic (temporal) changes in core assemblages resemble spatial differences in communities across the modern lagoon, from the southern marine sector to the northern brackish region. Similar temporal patterns have been reported from other Yucatan Peninsula lagoons and from cenotes (Nichupte, Aktun Ha), suggesting a regional coastal response to sea level rise and climate change, including geomorphic controls (longshore drift) on lagoon salinity, as observed today. Holocene barrier island development progressively protected the northwest Yucatan Peninsula coastline, reducing mixing between seawater and rain-fed submarine groundwater discharge. Superimposed on this geomorphic signal, assemblage changes that are observed reflect the most severe regional wet and dry climate episodes, which coincide with paleoclimate records from lowland lake archives (Chichancanab, Salpeten). Our results emphasize the need to consider coastal geomorphic evolution when using epikarst estuary and lagoon sediment archives for paleoclimate reconstruction and provide evidence of hydroclimate changes on the Yucatan Peninsula.

Human-Dog Bond in the Contemporary Mayab: Social Perceptions and Benefits Associated with the Hunter-Milpa Dog in Maya Peasant-Hunter Life Strategies in Yucatan, Mexico

Human-dog interaction has been examined in various sociocultural contexts, but such relationships have not been well explored for contemporary subsistence practices in Neotropical areas. In this study, we document human-dog bonds in terms of their relevance for Maya peasant-hunters' life strategies in a rural community of the Northwest Yucatan Peninsula. To better understand social perceptions of dogs, we gathered ethnographic data through semi-structured and in-depth interviews with Maya peasant-hunters and participant observation in a Maya community. We paid particular attention to the sociocultural dimensions of subsistence hunting, agriculture, and the everyday activities of peasant-hunters and their families. We found that most peasant-hunters recognized the versatility of dogs in hunting and as sentinels for agricultural and home-gardening practices. We also found that dogs transcend their utilitarian value by granting prestige to their owners through hunting and by protecting them from harmful non-human entities of Maya cosmovision. Based on our results, we propose the “hunter-milpa dog” as a category encompassing the unique bond forged between Maya peasant-hunters and their dogs. Our definition contributes to a more substantive understanding of these canines as social actors linked to the subsistence life strategies in rural settings of Mesoamerica.

Early Detection of Conflicts for the Management of Protected Areas: The Case of Charcoal Production in the Los Petenes Biosphere Reserve, Mexico

Management of conservation conflicts is a challenge of growing relevance for the effectiveness of protected areas worldwide, particularly in the case of socially inclusive areas such as biosphere reserves. For a successful management of the protected area, is critical to consider the social use of natural resources carried out by local populations linked to reserves, especially in socio-ecological contexts facing potential conservation conflicts (i.e., conflicts that have not yet arisen). We addressed the importance of an early detection of potential conflicts through the study of artisanal charcoal production by Yucatec Mayan communities located in the zone of influence of a biosphere reserve in Northwest Yucatan Peninsula, Mexico. Through semi-structured interviews with charcoal producers and in-depth interviews with environmental authorities linked to the reserve, we discuss the advantages associated to early detection of potential conservation conflicts for biosphere reserves' management.

Marine sponges (Porifera: Demospongiae) from the Gulf of México, new records and redescription of Erylus trisphaerus (de Laubenfels, 1953).

Marine sponges usually constitute the most diverse group of the benthic community in coral reefs. Although they are reasonably well studied at the northern Gulf of Mexico (GMx), the southern GMx is poorly known and lacks records from many major reef systems that lie off the Mexican coast. The present taxonomic study is the first sponge account from Alacranes reef, the largest coral reef system in the GMx, and from the shallow reef banks of Sisal, both in the northwest Yucatan Peninsula. The 19 species herein described represent the first sponge fauna records from these reefs. Among these, seven species represent new record for GMx: Erylus formosus, Cliona flavifodina, Spirastrella aff. mollis, Strongylacidon bermuda, Topsentia bahamensis, Agelas tubulata and Chelonaplysilla aff. erecta. Twelve species are new records for the Southern GMx: Erylus trisphaerus, Cliona amplicavata, Chondrilla caribensis, Halichondria lutea, Hymeniacidon caerulea, Axinella corrugata, Dragmacidon reticulatum, Chalinula molitba, Amphimedon caribica, A. complanata, Hyatella cavernosa and Dysidea variabilis. Additionally, a redescription of Erylus trisphaerus is presented which had not been reviewed since its original description in 1953 off Western Florida, except that it was listed for north La Habana, Cuba.

Bioarchaeological investigation of ancient Maya violence and warfare in inland northwest Yucatan, Mexico

This study investigates evidence of changes and continuities in ancient Maya violence and warfare in inland northwest Yucatan, Mexico from the Middle Preclassic (600-300 BC) to the Postclassic (AD 1050-1542) through bioarchaeological analysis of cranial and projectile trauma. It is hypothesized that the frequency of violence increases before the Classic Maya collapse and remains high during the Postclassic period. It is also hypothesized that the flat, open terrain was conducive to warfare and resulted in higher trauma frequencies than in other parts of the Maya area. Results show that the frequency of cranial trauma decreases before the Classic collapse and increases in the Postclassic, partially matching the expected chronological trends. The frequency of cranial trauma does not differ significantly from other Maya regions but the pattern does: for all periods, males have more healed injuries than females and they are concentrated on the left side of the anterior of the skull. Some injuries appear to be from small points hafted in wooden clubs. In addition, projectile trauma is evident in a scapula with an embedded arrowhead tip, the first such case reported in a Maya skeleton. Overall, these results suggest greater reliance on open combat and less on raids in this region compared with other parts of the Maya area, possibly due to the flat, open terrain, though the identification of perimortem trauma in both women and men indicates surprise raids on settlements were also practiced.

SACRED LANDSCAPES AND BUILDING PRACTICES AT UCI, KANCAB, AND UCANHA, YUCATAN, MEXICO

AbstractDuring the emergence of regional hierarchy around the site of Uci in northwest Yucatan, Mexico, ordinary people affected power relations in at least two ways. First, in the Late Preclassic and Early Classic periods, Uci had the largest ceremonial center and the largest population within a 20 km radius. Uci also physically linked itself to smaller settlements, such as Kancab and Ucanha, by means of a broad stone causeway. Yet Kancab and Ucanha's quadripartite placement of causeways and central plaza suggests that its households created a sacred landscape that gave them a degree of ritual autonomy. Ordinary people impacted power relations a second way by participating in the development of the megalithic architectural style, which was used in the region's most authoritative buildings. The use of this style in domestic platforms illustrates the ability of modest households to make their own decisions and to act in ways that constituted society at large.

3800 Years of Quantitative Precipitation Reconstruction from the Northwest Yucatan Peninsula

Precipitation over the last 3800 years has been reconstructed using modern pollen calibration and precipitation data. A transfer function was then performed via the linear method of partial least squares. By calculating precipitation anomalies, it is estimated that precipitation deficits were greater than surpluses, reaching 21% and <9%, respectively. The period from 50 BC to 800 AD was the driest of the record. The drought related to the abandonment of the Maya Preclassic period featured a 21% reduction in precipitation, while the drought of the Maya collapse (800 to 860 AD) featured a reduction of 18%. The Medieval Climatic Anomaly was a period of positive phases (3.8–7.6%). The Little Ice Age was a period of climatic variability, with reductions in precipitation but without deficits.

SOIL GEOCHEMICAL ANALYSES AT THE PRECLASSIC SITE OF XTOBO, YUCATAN, MEXICO

AbstractThe geochemical analysis of soil samples collected in association with archaeological remains has proven to be an effective tool in the identification of past human behaviors. These methodologies are here applied to the study of notable features from the site of Xtobo, Yucatan, Mexico. Xtobo is a Preclassic Maya regional center in northwest Yucatan exhibiting a complex settlement pattern, including a well-defined plaza, multiple raised causeways, and a ballcourt. In addition, the site includes a large defined open area, which was initially thought to be a potential marketplace. The results of the geochemical soil analyses identified several areas of food production and consumption throughout the site, along with potential craft production zones. The results in association with the potential marketplace were intriguing, but inconclusive.

XTOBO, YUCATAN, MEXICO, AND THE EMERGENT PRECLASSIC OF THE NORTHERN MAYA LOWLANDS

AbstractTraditionally, research on the Preclassic Maya has focused on settlements found in the Southern Maya Lowlands. Apart from work at a few well-known archaeological sites in the Northern Lowlands, such as Komchen, Dzibilchaltun, and Yaxuna, the Preclassic Northern Maya had received relatively little attention from scholars. In recent years, however, many previously unreported archaeological sites with Preclassic materials have come to light. In northwest Yucatan, Mexico, a survey carried out by Proyecto Costa Maya encountered 140 sites with Preclassic components, including the site of Xtobo. Xtobo stood out from its neighboring Preclassic sites due to its extent and the size and complexity of its architecture. In addition, initial surveys of the site suggested that it was never reoccupied after the Preclassic period, thereby making it a valuable site for studying the Preclassic period in the Northern Maya Lowlands. After three seasons of fieldwork, the Proyecto Arqueologico de Xtobo was able to build substantially on the initial findings of the Proyecto Costa Maya, mapping 67 ha of settlement, including 387 structures, and carrying out a stratified sample of test pit excavations throughout the site. The project documented a dense and well-organized settlement, which included complex architectural features, such as pyramids, triadic groups, elite residences, and a ballcourt. The settlement at Xtobo shows many signs of a complex sociopolitical organization and interaction with other areas of the Maya region and Mesoamerica. The results of the Proyecto Arqueologico de Xtobo indicate that the Northern Maya Lowlands were an important and integral part of Preclassic Mesoamerica and should be considered in larger cultural reconstructions of the time period.

Temporal trends in benthic macrofauna composition in response to seasonal variation in a tropical coastal lagoon, Celestun, Gulf of Mexico

Aquatic habitats in some tropical coastal environments can change seasonally, causing changes in the community structure of the benthic macrofauna. A tropical coastal lagoon, the Celestun lagoon, on the north-west Yucatan peninsula, was sampled seasonally and faunal, water and sediment data were compared with conditions during the 1994–1995 weather cycle across a grid of 12 sites distributed along the lagoon’s salinity gradient. Habitat variation was expressed as physical factors associated with the water column (e.g. salinity) and bottom sediments (e.g. interstitial salinity, texture), whereas the benthic community response was assessed through changes in species composition, diversity and dominance. Taxonomic dominance varied according to changes in seasonal habitat characteristics. During the season of strong northerly winds (‘nortes’), molluscs dominated and polychaetes almost disappeared. Polychaetes then recovered during the dry season, becoming as common as crustaceans and molluscs. Finally, during the rainy season, polychaetes became the dominant group and molluscs declined. A conceptual model summarising the community structure changes associated with key physical and biotic factors is proposed. The results indicate that the benthic community of the Celestun lagoon is a resilient one, largely driven by natural weather variability in this tropical ecosystem to a greater extent than previously suggested.

Benthic community response to habitat variation: A case of study from a natural protected area, the Celestun coastal lagoon

Little information currently exists on spatial and temporal benthic community variations in tropical coastal lagoons. Here, the benthic community response to habitat variation in the Celestun coastal lagoon, northwest Yucatan peninsula, was seasonally examined during the 1994–1995 climatic cycle into a grid of 12 sampling sites distributed along the salinity gradient of the lagoon. Habitat variation was assessed through physical factors associated both to the water column (e.g. salinity) and the bottom sediment (e.g. sand, silt and clay fractions). The benthic community response was assessed through species diversity measures and abundance. Under the influence of climatic seasonality, variations in habitat conditions followed by changes in the benthic community characteristics were expected. Results from two-way ANOVAs showed that for the period of study, Celestun lagoon was more heterogeneous along the spatial axis of variability than along the temporal one. Multiple regression analysis showed that salinity was spatially the main factor influencing the benthic community characteristics. Temporally, the sediment characteristics were observed to exert significant effects on the species diversity characteristics but not on abundance. Other variables assessed (dissolved oxygen, pH, temperature and water column transparency) exhibited no significant covariance with species diversity and abundance. Since generated from historical data, these results have the potential to be useful as a benchmark to the establishment of monitoring programs in the light of the increasing anthropogenic pressure on the natural resources of the lagoon and surrounding coastal area.

Bat assemblages in a naturally fragmented ecosystem in the Yucatan Peninsula, Mexico: species richness, diversity and spatio-temporal dynamics

Investigations of bats in naturally fragmented ecosystems may help refine assumptions about bat responses to fragmentation of their habitats by human activity. Bat species assemblages were studied for a 3.5-y period in a naturally fragmented landscape in the north-west Yucatan Peninsula, Mexico. Bats were systematically sampled using mist nets in a total of 16 forest islands of four categories (four sites each): large (> 20 ha), small ( 10 km or < 1 km away from the nearest forest island, respectively). We captured a total of 1134 bats representing 17 species. Bat diversity and species richness were similar among categories of forest island. Fruit-eating bats (78-93% of captures) were significantly more abundant in large and in small than in forest islands in the far or near categories. Differences in density of Manilkara zapota trees in the forest islands might underlie the observed variations in the abundance of frugivorous bats. Distances traversed by bats (0.65-38 km) between forest islands (typically 100-300 m away), facilitates the mobility of bats across the landscape. However, the moderately rich bat species assemblage detected, suggests that other species may not be able to persist in such naturally fragmented ecosystems.

Climate change on the Yucatan Peninsula during the Little Ice Age

We studied a 5.1-m sediment core from Aguada X'caamal (20° 36.6′N, 89° 42.9′W), a small sinkhole lake in northwest Yucatan, Mexico. Between 1400 and 1500 A.D., oxygen isotope ratios of ostracod and gastropod carbonate increased by an average of 2.2‰ and the benthic foraminifer Ammonia beccarii parkinsoniana appeared in the sediment profile, indicating a hydrologic change that included increased lake water salinity. Pollen from a core in nearby Cenote San José Chulchacá showed a decrease in mesic forest taxa during the same period. Oxygen isotopes of shell carbonate in sediment cores from Lakes Chichancanab (19° 53.0′N, 88° 46.0′W) and Salpeten (16° 58.6′N, 89° 40.5′W) to the south also increased in the mid-15th century, but less so than in Aguada X'caamal. Climate change in the 15th century is also supported by historical accounts of cold and famine described in Maya and Aztec chronicles. We conclude that climate became drier on the Yucatan Peninsula in the 15th century A.D. near the onset of the Little Ice Age (LIA). Comparison of results from the Yucatan Peninsula with other circum-Caribbean paleoclimate records indicates a coherent climate response for this region at the beginning of the LIA. At that time, sea surface temperatures cooled and aridity in the circum-Caribbean region increased.

Ring of Cenotes (sinkholes), northwest Yucatan, Mexico: Its hydrogeologic characteristics and possible association with the Chicxulub impact crater

A 180-km-diameter semicircular band of abundant karst sinkholes (Ring of Cenotes) in northwest Yucatan, Mexico, coincides approximately with a concentric ring of the buried Chicxulub structure, a circular feature manifested in Cretaceous and older rocks, that has been identified as the product of the impact of a bolide. The ring, expressed in Tertiary rocks, marks a zone of high permeability as shown by (1) the sinkholes themselves, (2) breaks in the coastal dune system and high density of springs where the ring intersects the coast, and (3) water-level transects characterized by a decline in water level toward the ring. Any direct relation that exists between the Ring of Cenotes and the Chicxulub structure bears on regional hydrogeology. If the layer or zone responsible for the ring is deeply buried, it may act as a barrier to the movement of ground water across the main flow direction. Shallower zones of horizontal permeability could result in less complete diversion of ground water. Through its influence on Yucatan aquifer characteristics, the ring may provide a link between modern environmental problems and astrogeology. Possible origins for the Ring of Cenotes are (1) faulting, perhaps reactivated by post-Eocene–mid-Miocene basin loading, (2) permeability in a buried reef complex developed in the shallow Paleocene sea around the crater rim, or (3) breccia collapse occasioned by consolidation or by solution of evaporite components. If the ring developed on ancient faults, it may outline hydrothermal systems and mineral deposits produced during Paleocene cooling of the Chicxulub melt sheet.

Early Boundary Maintenance in Northwest Yucatan, Mexico

Walls surrounding three sites in northwest Yucatan, Mexico, were observed in aerial photography. The walls are thought to have been constructed during the Pure Florescent (Terminal Classic) period and to postdate the architectural complexes at the sites they surround. The photographs also show causeways connecting satellite communities with major centers; these are interpreted as Classic period attempts at boundary maintenance. The apparent trend toward increased severity of such activity through time is considered the result of demographic, social, and ecological factors.