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Research about Yucatan Peninsula

Source-linked reports with geographic coverage including Yucatan Peninsula.

7 recordsLinked to original sources
USGS2021

First documentation of long-distance travel by a Florida manatee to the Mexican Caribbean

West Indian manatees ( Trichechus manatus ) are separated into two allopatric subspecies: the Florida manatee ( T. m. latirostris ) and the Antillean manatee ( T. m. manatus ). In the winter of 2020–2021, an adult manatee was sighted off the coast of Cancun, Quintana Roo, Mexico, in areas where Antillean manatees are not typically seen. The individual had distinct watercraft scars on its body, which were matched using photo-identification to a known male Florida manatee (PE424) that had been repeatedly photographed in Florida since 1998. This is the first record of a Florida manatee visiting the Mexican Caribbean. Previous reports of individuals from this subspecies in Cuba, combined with genetic evidence, suggest some level of connectivity among geographically separated manatee populations. We present the first evidence of along-distance movement by amanatee from Florida to the Yucatan Peninsula (Quintana Roo, Mexican Caribbean). This case, previous reports of Florida manatees in Cuba, and genetic evidence, suggest acertain degree of genetic mixture among the two subspecies.

Yucatan Peninsula↗
USGS2021

Local fruit availability and en route wind conditions are poor predictors of bird abundance and composition during fall migration in coastal Yucatán Peninsula

In migratory stopover habitats, bird abundance and composition change on a near daily basis. On any given day, the local bird community should reflect local environmental conditions but also the environments that birds encountered previously along their migratory route. For example, during fall migration, the coast of the Yucatán Peninsula in Mexico receives birds that have just crossed the Gulf of Mexico and their abundance and composition may be associated with regional factors such as wind conditions experienced on previous dates. Other factors, such as local fruit availability, may also influence daily variation in bird abundance and composition. Using mist net data from 2 coastal national parks in the Yucatán Peninsula during fall migration in 2016 and 2017, we did not find a strong association between daily changes in bird abundance or community composition with wind conditions and ripe fruit availability. Thus, despite wind and fruit being known to be important to individual birds (influencing stopover duration and departure decisions), their effects might not scale up to be drivers of population and community level variation. On the other hand, we found that the 2 sites shared only about half of their species and those shared species had different temporal abundance patterns at each site. Site and year differences in temporal patterns of migration might arise because populations of the same species are on different migration routes and schedules. While bird arrival is not timed to hit peaks in fruit production in our study sites, whether bird–resource mismatch is a general characteristic of tropical coastal stopover habitats requires further research. If birds on migration have adapted to seasonal variation in food availability, they might be equipped to deal with the additional variability in food supply that is expected to occur with climate change.

Yucatan Peninsula↗
USGS2017

Methane- and dissolved organic carbon-fueled microbial loop supports a tropical subterranean estuary ecosystem

Subterranean estuaries extend inland into density-stratified coastal carbonate aquifers containing a surprising diversity of endemic animals (mostly crustaceans) within a highly oligotrophic habitat. How complex ecosystems (termed anchialine) thrive in this globally distributed, cryptic environment is poorly understood. Here, we demonstrate that a microbial loop shuttles methane and dissolved organic carbon (DOC) to higher trophic levels of the anchialine food web in the Yucatan Peninsula (Mexico). Methane and DOC production and consumption within the coastal groundwater correspond with a microbial community capable of methanotrophy, heterotrophy, and chemoautotrophy, based on characterization by 16S rRNA gene amplicon sequencing and respiratory quinone composition. Fatty acid and bulk stable carbon isotope values of cave-adapted shrimp suggest that carbon from methanotrophic bacteria comprises 21% of their diet, on average. These findings reveal a heretofore unrecognized subterranean methane sink and contribute to our understanding of the carbon cycle and ecosystem function of karst subterranean estuaries.

Yucatan Peninsula↗
USGS1995

Water management by early people in the Yucatan, Mexico

The Yucatan Peninsula is a coastal plain underlain by permeable limestone and receives abundant rainfall. Such hydrogeologic conditions should provide major supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that limits the amount of fresh water available. Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed on extensive use of groundwater. The religion was water oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management, primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supply by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution. A historical perspective of a paper such as this provides insight into the attitudes concerning water of early people and perhaps provides insight into current attitudes concerning water. Hydrogeologists possess the expertise to generate relevant information required by water managers to arrive at management programs to achieve sustainable development. ?? 1995 Springer-Verlag.

Yucatan Peninsula↗
USGS1985

Dolomitization in a mixing zone of near-seawater composition, Late Pleistocene, northeastern Yucatan Peninsula

Patches of dolomite occur in cores of reefal limestone from the shallow subsurface on the northeastern coast of the Yucatan Peninsula. This limestone accumulated during an interglacial high stand of sea level about 200,000 years ago. Dolomitization was preceded by freshwater diagenesis, including precipitation of sparry calcite cement, stabilization of Mg-calcitic skeletal fragments, and partial dissolution of aragonitic components. This suggests a predolomitization lowering of sea level with the consequent freshening of pore water. The subsequent precipitation of dolomite indicates a return to high sea level with the consequent increase in Mg/Ca ratio of pore water. Dolomitization took place during a brief high stand of sea level, either shortly after deposition about 200,000 yr BP, or, more likely, about 125,000 yr BP. Dolomite occurs both as microcrystalline replacement dolomite and as cement. The cement is part of the following diagenetic sequence: 1) limpid euhedral-subhedral calcian dolomite crystals, 2) zoned dolomite crystals with zones formed by variations of the calcium/magnesium ratio in dolomite, 3) layers of alternating calcian dolomite and magnesian calcite or calcite, and 4) calcite. This sequence represents the progressive freshening of ground water during the initial stage of a fall in sea level. Average cation composition of the limpid dolomite cement is Ca 57 Mg 43 (electron microprobe analysis). Zoned cement crystals are composed of Ca (sub 57-59) Mg (sub 43-41) layers and Ca 62 Mg 38 layers. Most of the higher-calcium dolomite layers are dissolved, forming hollow-zone crystals. In cement with alternating dolomite and calcite zones, the calcite is Ca (sub 99-97) Mg (sub 1-3) (low-Mg calcite) and Ca (sub 96-93) Mg (sub 4-7) (Mg calcite). The dolomite and Mg calcite zones are partially to totally leached. delta 18 O compositions of Yucatecan dolomite and of modern ground water suggest dolomite precipitation from mixed water ranging from about 75% seawater, 25% freshwater to nearly all seawater. (Isotope analyses are for the most stable calcian dolomites; more soluble, calcium-rich dolomite presumably is analyzed with calcite and thought to be isotopically lighter than the less soluble dolomite.) In the cement sequence, the most stable dolomite is followed by more soluble dolomite as ground water becomes less saline. Isotope analyses, together with position of dolomite in the cement sequence, suggest the most stable calcian dolomite (including limpid dolomite) precipitated from mixed water with large proportions of seawater, and the less stable, more calcian dolomite precipitated from fresher mixed water.

Yucatan Peninsula↗
USGS1980

Chemical mass-wasting of the northern Yucatan Peninsula by groundwater dissolution

The northern part of the Yucatan Peninsula is a relatively flat, low-lying carbonate terrane with no geomorphic expressions of stream channels. It is estimated that mean annual recharge to the groundwater system is 150 mm. For the 65,500 km 2 study area, mean annual discharge (equivalent to recharge) is 9.8 × 10 9 m 3 , or 8.6 × 10 6 m 3 for each 1 km of the 1,100-km-long coastline. In the interior of the peninsula, the recharging water annually dissolves about 37.5 t (metric tons) of calcite per 1 km 2 . When the groundwater has become saturated with calcite, little additional water-rock interaction occurs until the active mixing (dispersion) zone is reached near the coastline. Theoretical calculations and laboratory experiments have shown that when two waters, each calcite saturated and with different salinities, are mixed, the resulting solution generally becomes undersaturated with calcite and, therefore, is capable of dissolving additional calcite. On the basis of our study of the Xel Ha lagoon on the east coast of Yucatan, we calculate that as much as 1.2 mmol/L additional calcite can be dissolved in the brackish groundwater zone of dispersion. This indicates that if the total solution potential of the amount of water discharging at Xel Ha has focused within the lagoon area, the lagoon could be chemically incised in less than 3,000 yr. We postulate that chemical mass wasting by dissolution in the zone of groundwater mixing is an important geomorphic process in coastal areas of limestone terranes.

Yucatan Peninsula↗