Climate and ocean variability during the middle and late Holocene recorded in laminated sediments from Alfonso Basin, Gulf of California, Mexico

AbstractA laminated sequence (core BAP96-CP 24°38.12′N, 110°33.24′W; 390 m depth) from the Alfonso Basin in Bay of La Paz, southern Gulf of California, contains a record of paleoceanographic and paleoclimatic changes of the past 7900 yr. Radiolarian assemblages and magnetic susceptibility are used as proxies of oceanographic and climatic variability. The records provide a regional scenario of the middle and late Holocene, suggesting two major climatic regimes and several millennial-scale events. Conditions relatively warmer and drier than today occurred from ∼7700 to 2500 cal yr BP, promoting the intensification of evaporation processes and the prevalence of the Gulf of California water in the Basin. These conditions correlate with strong droughts in the middle Holocene of North America and with minimal incursion of tropical waters into the Gulf of California. Proxies indicate a warm scenario and the dominance of the Equatorial Surface Water in the Alfonso Basin from ∼2400 to 700 cal yr BP, suggesting the intensification of ENSO cycles. A climatic signal between ∼1038 and 963 cal yr BP may be correlated with global signal of the “Medieval Warm Period.” Several cooling events are recognized at 5730, 3360, 2700, 1280 and 820 cal yr BP and are associated with intensification of northwest winds leading to upwellings and enhanced productivity in the Basin.

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Late Holocene Lacustrine Chronology and Archaeology of Ancient Lake Cahuilla, California

Quaternary Research ◽

10.1016/0033-5894(83)90042-x ◽

1983 ◽

Vol 19 (3) ◽

pp. 373-387 ◽

Cited By ~ 64

Author(s):

Michael R. Waters

Keyword(s):

Gulf Of California ◽

Late Holocene ◽

Colorado River ◽

Archaeological Sites ◽

Ancient Lake ◽

Freshwater Lakes ◽

Radiocarbon Dates ◽

California Water ◽

Salton Trough ◽

Lake Cahuilla

AbstractFreshwater lakes existed intermittently in the Salton Trough of southern California during the late Holocene. The lakes formed north of the subaerial Colorado River Delta whenever the Colorado River flowed west into the trough instead of south to the Gulf of California. Water filled the trough to a maximum altitude of 12 m. Stratigraphy, radiocarbon dates, and supplementary evidence document four lacustral intervals of Lake Cahuilla between A.D. 700 and 1580. Archaeological sites are associated with the 12-m shoreline and their occupation correlates with these lacustral intervals.

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Hydrological changes and paleoproductivity in the Gulf of California during middle and late Holocene and their relationship with ITCZ and North American Monsoon variability

Quaternary Research ◽

10.1016/j.yqres.2012.11.007 ◽

2013 ◽

Vol 79 (2) ◽

pp. 138-151 ◽

Cited By ~ 20

Author(s):

Ligia Pérez-Cruz

Keyword(s):

North American ◽

Gulf Of California ◽

Late Holocene ◽

Tropical Pacific ◽

North American Monsoon ◽

The North ◽

Monsoon Variability ◽

Monsoonal Precipitation ◽

Central Atlantic ◽

Middle And Late Holocene

AbstractThis study investigates changes in precipitation patterns and variations in paleoproductivity in the tropical Pacific region associated with the North American Monsoon, Intertropical Convergence Zone (ITCZ) latitudinal migration, and changes in insolation during the middle and late Holocene. Major and trace element records (Al, Ba, C, K, Si and Ti) and Zr/Al and Ba/Al ratios in a core from Alfonso Basin, southern Gulf of California, are used as proxies of terrigenous input and bio-productivity. Records reveal an increase in precipitation and low bio-productivity ca. 6200 to 2400 cal yr BP, associated with the strengthening of monsoonal precipitation and northward shift of the ITCZ mean position in the eastern tropical Pacific. A multi-centennial drought from ca. 2400 to 1900 cal yr BP, and a dry and cold interval ca. 700 and 500 cal yr BP, are characterized by strong aeolian input and enhanced productivity, associated with diminution of the summer monsoonal precipitation and reduced insolation in the Northern Hemisphere and more southerly ITCZ position. Correlation of Alfonso Basin records with other records in the Gulf of California and the Pigmy and Cariaco basins in the Gulf of Mexico and central Atlantic provides constraints on NAM, ITCZ migration, and insolation-driven changes.

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Laminated sediments in the Bay of La Paz, Gulf of California: a depositional cycle regulated by pluvial flux

Sedimentology ◽

10.1046/j.1365-3091.2002.00505.x ◽

2002 ◽

Vol 49 (6) ◽

pp. 1401-1410 ◽

Cited By ~ 21

Author(s):

A. Molina-Cruz ◽

L. Perez-Cruz ◽

M. A. Monreal-Gomez

Keyword(s):

Gulf Of California ◽

Laminated Sediments ◽

La Paz ◽

Depositional Cycle

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Linking Habitat and Associated Abiotic Conditions to Predict Fish Hotspots Distribution Areas within La Paz Bay: Evaluating Marine Conservation Areas

Diversity ◽

10.3390/d13050212 ◽

2021 ◽

Vol 13 (5) ◽

pp. 212

Author(s):

Francisco Javier Urcádiz-Cázares ◽

Víctor Hugo Cruz-Escalona ◽

Mark S. Peterson ◽

Rosalía Aguilar-Medrano ◽

Emigdio Marín-Enríquez ◽

...

Keyword(s):

Gulf Of California ◽

Management Plan ◽

Marine Conservation ◽

Fish Diversity ◽

Rocky Shores ◽

Conservation Areas ◽

Niche Modelling ◽

La Paz ◽

Abiotic Conditions ◽

Presence Data

Hotspots are priority marine or terrestrial areas with high biodiversity where delineation is essential for conservation, but equally important is their linkage to the environmental policies of the overall region. In this study, fish diversity presences were linked to abiotic conditions and different habitat types to reveal multi-species and hotspots models predicted by ecological niche modelling methods within the Bay of La Paz, Mexico (south of Gulf of California). The abiotically suitable areas for 217 fish species were identified based on historical (1975–2020) presence data sets and a set of environmental layers related to distances from mangroves and rocky shores habitats, marine substrate, and bottom geomorphology conditions. Hotspot model distribution was delineated from a multi-species model identifying areas with ≥60 species per hectare and was compared to the marine conservation areas such Balandra Protected Natural Area (BPNA), illustrating how these models can be applied to improve the local regulatory framework. The results indicate that (1) there is a need for the BPNA to be enlarged to capture more of the delineated hotspot areas, and thus an update to the management plan will be required, (2) new conservation areas either adjacent or outside of the established BPNA should be established, or (3) Ramsar sites or other priority areas should be subject to legal recognition and a management plan decreed so that these vital habitats and fish diversity can be better protected.

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Human occupation strategies and related environmental-climate during the middle and late Holocene in central Pampas of Argentina

The Holocene ◽

10.1177/0959683618810407 ◽

2018 ◽

Vol 29 (2) ◽

pp. 244-261 ◽

Cited By ~ 4

Author(s):

Pablo G Messineo ◽

Marcela S Tonello ◽

Silvina Stutz ◽

Alfonsina Tripaldi ◽

Nahuel Scheifler ◽

...

Keyword(s):

Late Holocene ◽

Specific Activity ◽

Climatic Conditions ◽

Hard Material ◽

Human Occupation ◽

Climate Conditions ◽

Lithic Assemblage ◽

Depositional Rate ◽

Archeological Site ◽

Middle And Late Holocene

The main objective of this work is to generate and integrate interpretations of human occupation strategies and inferences of the environmental-climatic conditions in the central Pampas during the middle and late Holocene. We present a novel archeological–geological–paleoecological analysis in the area of the Cabeza de Buey lake, placed in an aeolian landscape. During the middle Holocene, two events of human occupations were recognized at Laguna Cabeza de Buey 2 archeological site. Both events present a small amount of lithic materials, a low diversity of tools and activities developed with them (principally hard material), and the hunting and primary processing of artiodactyls. These evidences suggest a locus of specific activity associated with an ephemeral human settlement under climate conditions drier than present and the presence of small, brackish, and shallow water bodies. For the late late Holocene, the hunter-gatherer occupation has a higher depositional rate of lithic assemblage, stones with diverse origins, presence of pottery fragments, a great lithic tool diversity, knapping techniques, and activities developed with these tools (processing wood, bone, hide, non-woody plant, and soft material). These evidences reveal an occupation with a higher degree of recurrence represented by a locus of multiple activities associated with a more stable landscape, such as an environment of dunes fixed by grass vegetation, and the establishment of a permanent water body. The different environmental characteristics for the middle and late Holocene in this area promoted that human groups develop two different patterns of mobility, settlement and use of space.

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A MULTI-SPECIES MICROALGAE BLOOM IN BAHIA DE LA PAZ, GULF OF CALIFORNIA, MEXICO (JUNE 2008)

CICIMAR Oceánides ◽

10.37543/oceanides.v24i1.50 ◽

2009 ◽

Vol 24 (1) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

I. Gárate-Lizárraga ◽

C. J. Band-Schmidt ◽

F. Aguirre-Bahena ◽

T. Grayeb del Alamo

Keyword(s):

Phytoplankton Biomass ◽

Gulf Of California ◽

Phytoplankton Community ◽

Red Tide ◽

Total Density ◽

La Paz ◽

Gyrodinium Instriatum ◽

High Species Richness ◽

Myrionecta Rubra ◽

Ecological Importance

Red tide patches were observed in Bahía de La Paz in June 17 and 18 of 2008. According to temperature and wind data this bloom occurred under upwelling-like conditions. Examination of the red tide samples showed the ciliate Myrionecta rubra and the naked dinoflagellates Gyrodinium instriatum and Katodinium glaucum as the main species responsible for this bloom. Total density (microalgae and ciliate) at the sampling stations was similar on both days, varying from 4607 × 103 cells L-1 to 4976 × 103 cells L-1 on the first day, and from 4172 × 103 cells L-1 to 5024 × 103 cells L-1 on the second day. Phytoplankton biomass (chlorophyll a) observed during the first day of the bloom was 1.5 mg m-3. Dinoflagellates and diatoms were the most numerically important phytoplankton groups. The phytoplankton community showed a high species richness, particularly heterotrophic dinoflagellates and ebridians. The ecological importance of the heterotrophic component of naked dinoflagellates and the ebriids for this bay is discussed. Florecimiento multiespecífico de microalgas en la Bahía de La Paz, Golfo de California, México (Junio, 2008) Durante los días 17 y 18 de junio de 2008, se observó una marea roja en la Bahía de La Paz. De acuerdo con los datos de temperatura y de vientos, este florecimiento ocurrió bajo condiciones muy similares a las de una surgencia. El examen de las muestras de marea roja revelaron que el ciliado Myrionecta rubra y los dinoflagelados desnudos Gyrodinium instriatum y Katodinium glaucum fueron las principales especies responsables de esta proliferación. La densidad total (microalgas y ciliado) fue similar en ambos días, variando de 4607 × 103 céls L-1 a 4976 × 103 céls L-1 durante el primero y entre 4172 × 103 céls L-1 y 5024 × 103 céls L-1 el segundo día, respectivamente. La biomasa fitoplanctónica (clorofila a) medida durante el primer día del florecimiento fue de 1.5 mg m3. Los dinoflagelados y las diatomeas fueron los dos grupos del fitoplancton numéricamente más importantes. Se observó una comunidad fitoplanctónica con una alta riqueza de especies, particularmente de dinoflagelados y ebriidos heterotróficos. Se discute la importancia del componente heterotrófico de los dinoflagelados desnudos y ebriidos.

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Bio-optical characterization of the waters of the Bay of La Paz, southern Gulf of California, during late spring 2004

Revista de biología marina y oceanografía ◽

10.22370/rbmo.2019.54.3.2031 ◽

2020 ◽

Vol 54 (3) ◽

pp. 343

Author(s):

Erik Coria-Monter ◽

María Adela Monreal-Gómez ◽

David Alberto Salas de León ◽

Elizabeth Durán-Campos

Keyword(s):

Primary Production ◽

Gulf Of California ◽

Net Primary Production ◽

Light Extinction ◽

La Paz ◽

Light Extinction Coefficient ◽

Production Values ◽

Subsequent Calculation ◽

Natural Fluorescence ◽

Community Growth

Information on selected bio-optical properties and primary production values of the waters of the Bay of La Paz, southern Gulf of California, is reported during June 2004, a region characterized to have very rich biodiversity, including endemic and endangered species, with high ecological relevance. In-situ measurements of natural fluorescence and photosynthetically available radiation (PAR) enabled the subsequent calculation of the incident irradiance (E0), the light extinction coefficient (k), compensation depth (Zc) and critical depth (Zcr). The results suggest the presence of light propitious conditions for phytoplankton community growth and net primary production, which are highly significant for the potential development of models of light penetration, ocean color, primary productivity, and analyses of organic carbon energy flow.

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