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East-central Florida pre-Columbian wood sculpture: Radiocarbon dating, wood identification and strontium isotope studies
Abstract
Highlights
•14C results for four east-central Florida carvings (Hontoon Island; Tomoka State Park) range ca. AD 1300-1600, spanning the proto-historic/historic periods
•87Sr/86Sr results for two of the three Hontoon carvings are consistent with the immediate locale, while the third suggests a different provenance
•Pinus sp. was used at Hontoon, while Peltophorum sp., currently not native to Florida, was used at Tomoka
... While a large number of studies have focussed on measuring Sr isotopes in archeological human and animal remains (e.g., Price et al., 2006;Bentley, 2013;Laffoon et al., 2014) or charred/carbonized grains (e.g., Benson et al., 2010; though not always successfullysee Styring et al., 2019), as well as on modern plants to establish a biologically available Sr baseline (e.g., Evans et al., 2010;Snoeck et al., 2016Snoeck et al., , 2020, less has been done with archeological wood remains. Exceptions include a study of the well-preserved desiccated structural timbers at Chaco Canyon (English et al., 2001), and of desiccated prehistoric willow and tule textiles in the Great Basin (Benson et al., 2006), as well as some more recent work on pre-Columbian wood sculptures from Florida (Ostapkowicz et al., 2017a) and Trinidad (Ostapkowicz et al., 2017b), waterlogged shipwrecks (Rich et al., 2016;Hajj et al., 2017;Van Ham-Meert et al., 2020), and South American/Lesser Antillean wooden clubs from museum collections (Ostapkowicz et al., 2018). Little targeted research has focused on pretreatments for archeological wood. ...
... Similarly, no pre-treatment was carried out by Hajj et al. (2017) prior to analysis of the Ribadeo, a sixteenth century Spanish shipwreck. The few studies that have so far investigated pretreatments for Sr isotope analysis of wood recovered from natural pitch (Ostapkowicz et al., 2017b) or on which consolidants have been applied (Ostapkowicz et al., 2017a(Ostapkowicz et al., , 2018 have used the pre-treatments commonly used in radiocarbon dating to remove carbon contamination (Brock et al., 2010(Brock et al., , 2017. These pre-treatments showed that such carbon contamination can be successfully removed adequately using different organic solvents and acid-base-acid (ABA) steps (Brock et al., 2010(Brock et al., , 2017Dee et al., 2011;Ostapkowicz et al., 2012Ostapkowicz et al., , 2013. ...
... To test the impact of pitch on the 87 Sr/ 86 Sr isotope composition of wood samples, three modern wood samples from Trinidad (T34, T71, and T81 - Ostapkowicz et al., 2017b) were selected and about 5 g of each were placed in 50 mL pitch obtained from southwest Trinidad's Pitch Lake for 3 months ( Table 1). Two aliquots of the pitch (ca. ...
Strontium isotope ratios (⁸⁷Sr/⁸⁶Sr) are commonly used in archeological and forensic studies to assess if humans and fauna are local to the place they were found or not. This approach is largely unexplored for wooden artifacts recovered in archeological contexts, as wood – in the rare instances it does survive – is often poorly preserved. One of the most common ways wood is preserved is through the anoxic conditions found in waterlogged contexts. A more unusual form of preservation is through submergence in natural pitch. These depositional media contribute their own strontium values to the in vivo ⁸⁷Sr/⁸⁶Sr wood values, which needs to be removed prior to analysis. Here we test several pre-treatment methods to remove potential strontium contamination from wood samples that were artificially immersed in seawater and pitch from Trinidad’s Pitch Lake. Water rinses and acid-leaching tests were carried out with hydrochloric acid and acetic acid to remove exogenous strontium from experimentally waterlogged wood. These tests removed large amounts of strontium from the samples and did not enable the recovery of the endogenous ⁸⁷Sr/⁸⁶Sr signal. For samples artificially immersed in pitch, the pre-treatments tested were based on radiocarbon dating procedures and carried out with and without the aqueous-based acid-base-acid (ABA) step. The use of organic solvents alone (methanol and toluene) removed exogenous strontium originating from the pitch. However, the ABA step eliminates large amounts of in vivo strontium from the samples. These tests show that ⁸⁷Sr/⁸⁶Sr values of wood are altered by the presence of pitch and water. With adequate pre-treatment using exclusively organic solvents, it may be possible to remove this contamination for samples immersed in pitch. However, the aqueous-based ABA pre-treatment should be avoided. The removal of contamination from waterlogged samples was unsuccessful with the current pre-treatment protocols and more research is needed. More importantly, and unexpectedly, ⁸⁷Sr/⁸⁶Sr values may extend outside of the mixing line between the wood’s endogenous strontium and the water. These results indicate the need for extreme caution when attempting to determine the provenance of waterlogged wood.
... wood; 5^^C = -27.6%o) and its probable origin has been investigated using strontium isotope analysis (see Ostapkowicz et al. 2017). Today the nearest Brazilwood is found in Cuba and the Bahamas, so it is possible that the wood arrived in Florida as driftwood. ...
... This information is known for only a few of the figurines. Confirmation of the wood type can be accomplished by a specialist in wood identification, strontium analysis can help identify the place of origin (e.g., Ostapkowicz et al. 2017), and an AMS radiocarbon date would require only a tiny sample from each object. With the exception of the Salt Springs object, most of the Florida wooden figurines are presumed to be from the late pre-contact or early contact period, but without direct dating, there is no assurance of this. ...
In 2013, the Padgett figurine, a pre-Columbian wooden statuette, was donated to the Florida Museum of Natural History. In this chapter, I describe the object and situate it among nine other known wooden statuettes from Florida. Finally, I discuss various interpretations of these objects and suggest avenues for further study.
... And, although we cannot excavate a "clan" system, we argue that such institutions were likely part and parcel of regularized councils. In fact, some of the larger posts erected on the mound at Cold Spring could be interpreted as clan markers, like those excavated elsewhere in the Southeast, such as the large owl effigy post recovered from Hontoon Island, Florida (Ostapkowicz et al. 2017). More broadly, the regional spread of some of the institutions associated with platform mound construction, and possibly council houses as well, may have been engendered by social institutions such as clans or subclans. ...
Democratic cooperation is a particularly complex type of arrangement that requires attendant institutions to ensure that the problems inherent in collective action do not subvert the public good. It is perhaps due to this complexity that historians, political scientists, and others generally associate the birth of democracy with the emergence of so-called states and center it geographically in the “West,” where it then diffused to the rest of the world. We argue that the archaeological record of the American Southeast provides a case to examine the emergence of democratic institutions and to highlight the distinctive ways in which such long-lived institutions were—and continue to be—expressed by Native Americans. Our research at the Cold Springs site in northern Georgia, USA, provides important insight into the earliest documented council houses in the American Southeast. We present new radiocarbon dating of these structures along with dates for the associated early platform mounds that place their use as early as cal AD 500. This new dating makes the institution of the Muskogean council, whose active participants have always included both men and women, at least 1,500 years old, and therefore one of the most enduring and inclusive democratic institutions in world history.
... Literature review of cleaning methods for isotopic analysis of waterlogged wood (Bird et al., 2014;Von Holstein et al., 2015;Ostapkowicz et al., 2017, Snoeck et al. submitted, Brinkkemper et al., 2018Rich et al. 2012Rich et al. , 2016aMillion et al., 2018;Andreu-Hayles et al., 2019;Büntgen et al., 2020 During immersion in seawater there usually is little bacterial degradation of the wood. Once the timbers are lifted out of the water and come in contact with oxygen, bacterial degradation occurs rapidly. ...
Sr isotopes represent a potential means to trace the provenance of archaeological timber. Such tracing allows us to examine the transport, by past people, of wooden objects and of wood and timber as a raw material. However, issues exist with the mobility of Sr and addition of exogenous Sr during waterlogging. This paper presents a systematic assessment of cleaning methods to remove exogeneous Sr from waterlogged wood. Neither a large number of Milli-Q washes, a combination of MQ and Hydrofluoric acid (HF) or alpha-cellulose extraction were able to retrieve the original signature. It was also shown that ashing leads to higher uncertainties due to the smaller amount of Sr available for analysis, this method will only be really useful when large samples are available, is not recommended for small archaeological samples. Our studies also highlight that the distribution of Sr in waterlogged wood is highly heterogeneous.
... Ohlídalová et al. 2006) and pyrolysis-GC/MS (e.g. Nishimoto 2011;Ostapkowicz et al. 2017). However, these techniques are not always infallible, depending on detection limits and the fact that some conservation treatments are not chemically distinguishable from the samples to which they have been applied (e.g. ...
To achieve a reliable radiocarbon ( ¹⁴ C) date for an object, any contamination that may be of a different age must be removed prior to dating. Samples that have been conserved with treatments such as adhesives, varnishes or consolidants can pose a particular challenge to ¹⁴ C dating. At the Oxford Radiocarbon Accelerator Unit (ORAU), common examples of such substances encountered include shellac, the acrylic polymers Paraloid B-67 and B-72, and vinyl acetate-derived polymers (e.g. PVA). Here, a non-carbon-containing absorbent substrate called Chromosorb ® was deliberately contaminated with a range of varieties or brands of these conservation treatments, as well as two cellulose nitrate lacquers. A selection of chemical pretreatments was tested for their efficiency at removing them. While the varieties of shellac and Paraloid tested were completely removed with some treatments (water/methanol and acetone/methanol/chloroform sequential washes, respectively), no method was found that was capable of completely removing any of the vinyl acetate-derived materials or the cellulose nitrate lacquers. While Chromosorb is not an exact analog of archaeological wood or bone, for example, this study suggests that it may be possible to remove aged shellac and Paraloid from archaeological specimens with standard organic solvent-acid-base-acid pretreatments, but it may be significantly more difficult to remove vinyl acetate-derived polymers and cellulose nitrate lacquers sufficiently to provide reliable ¹⁴ C dates. The four categories of conservation treatment studied demonstrate characteristic FTIR spectra, while highlighting subtle chemical and molecular differences between different varieties of shellac, Paraloid and cellulose nitrate lacquers, and significant differences between the vinyl acetate derivatives.
In this book, Lee A. Newsom offers an overview of wood in archaeology --how and where it is preserved and analyzed, its relevance to paleoecological and paleoenvironmental questions, as well as its role as an important source of information in modern archaeological science and related historical disciplines. Her book addresses a range of questions about wood reliance practices, sustainability, and the overall relevance of forest ecosystems to past cultures and cultural evolution. Newsom provides a step-by-step treatment of archaeological analysis with clear explanations and examples from various corners of the world. She also shows how the study of archaeological wood is relevant to modern restoration ecology and conservation biology that tracks long-term ancient ecosystems, including questions of global change. Demonstrating the vital role of wood and timber resources to past human societies, her book will interest scholars and students of archaeology, historical ecology, paleoecology, and wood science.
Museums hold millions of objects from all over the globe, offering a unique, unparalleled resource for researchers. They provide historical snapshots of data both geographically and through time, giving researchers rare access to huge amounts of information. Recent advances in analytical techniques have allowed for even more information to be obtained from collections, from radiocarbon dating to genetic sequencing. This entry provides some background on museums and their collections, along with key examples of research that has been undertaken using both nondestructive and destructive sampling methods. It also outlines details on how collections can be used, limitations in sampling, and how to search for objects in museums across Britain. The potential for collections to assist with research is enormous, and this applies not only to national museums but also to smaller regional museums.
This chapter explores the context of the three monumental animal and bird carvings found at the Hontoon/Thursby site on the St. Johns River: the owl, otter, and pelican. Archaeological and ethnographic information from Florida and surrounding areas is brought to play in interpreting the carvings and their placement at the site.
The Mill Cove Complex is an early Mississippi period settlement and mortuary center situated near the mouth of the St. Johns River, Florida. The complex consists of habitation and ritual middens, earthen causeways, and the Grant and Shields mounds. Although situated on the outskirts of the Mississippian world, residents of Mill Cove acquired exotic artifacts and raw materials from far-flung areas of eastern North America, including Cahokia. Focusing on a special event or ritual midden known as Kinzey’s Knoll, this chapter explores social memory and the use of pieces of the past in ritual at Mill Cove.
Inside Wood is an Internet-accessible wood anatomy reference, research, and teaching tool. The Inside Wood database has coded wood anatomical descriptions based on the IAWA List of Microscopic Features for Hardwood Identification and is accompanied by a collection of photomicrographs. As of November 2010 there were over 5,800 descriptions and 36,000 images of modern woods, and over 1,600 descriptions and 2,000 images of fossil woods. CITES-listed timber species and other endangered woody plants are included in this digital collection hosted by North Carolina State University's library. This web site has value in helping with wood identification because it has a multiple entry key that allows searching by presence or absence of IAWA features and it serves as a virtual reference collection whereby descriptions and images can be retrieved by searching by scientific or common name or other keywords.
We compared the accuracy of different combinations of natural markers, specifically otolith elemental (Sr:Ca and Ba:Ca) and isotopic ratios (87:86Sr) with and without genetic stock constraints to evaluate their ability to distinguish among anadromous river herring (i.e., alewife, Alosa pseudoharengus, and blueback herring, Alosaaestivalis) populations from their US ranges. Model accuracy increased when constrained to a regional level by genetic stocks. Both species were misclassified to sites up to 1000 km from their collection location when only otolith chemistry was used. The inclusion of genetic constraints improved reclassification rates, and the longer time scale of genetic variation makes this method less sensitive to interannual variation. We recommend the combined approach of otolith chemistry and genetics as a means to trace river herring in marine bycatch back to river of origin.
The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from 14C measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived from the data using the random walk model (RWM) used to generate IntCal09 and Marine09, which has been revised to account for additional uncertainties and error structures. The new curves were ratified at the 21st International Radiocarbon conference in July 2012 and are available as Supplemental Material at www.radiocarbon.org. The database can be accessed at http://intcal.qub.ac.uk/intcal13/. © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.
Variations in the strontium isotope ratio (87Sr/86Sr) of tooth enamel are used to examine the migration patterns of late Pleistocene mammoths and mastodons from Florida. An animal's 87Sr/86Sr ratio tracks the ratios of its environment, which vary with differences in bedrock and soil. Consequently, the environmentally controlled differences in 87Sr/86Sr ratio recorded in mineralized tissue, such as tooth enamel, may be used to reconstruct the movement patterns of an individual. We map variations in local 87Sr/86Sr ratios across modern Florida and Georgia through analysis of rodent teeth, plants, and surface water, then use this map to interpret the movement patterns of extinct mammals. Mastodons from northern and central Florida have higher 87Sr/86Sr ratios than both modern environmental samples from Florida and fossils from nonmigratory species, suggesting that mastodons migrated north into Georgia. Mammoths display ratios similar to those of environmental samples and resident species, suggesting that they did not migrate outside Florida.
A detailed record of the strontium-87 to strontium-86 ratio in seawater during the last 100 million years was determined by
measuring this ratio in 137 well-preserved and well-dated fossil foraminifera samples. Sample preservation was evaluated from
scanning electron microscopy studies, measured strontium-calcium ratios, and pore water strontium isotope ratios. The evolution
of the strontium isotopic ratio in seawater offers a means to evaluate long-term changes in the global strontium isotope mass
balance. Results show that the marine strontium isotope composition can be used for correlating and dating well-preserved
authigenic marine sediments throughout much of the Cenozoic to a precision of ±1 million years. The strontium-87 to strontium-86
ratio in seawater increased sharply across the Cretaceous/Tertiary boundary, but this feature is not readily explained as
strontium input from a bolide impact on land.
In this paper, we summarize the main chemical pretreatment protocols currently used for AMS radiocarbon dating at the Oxford Radiocarbon Accelerator Unit, updating the protocols last described by Hedges et al. (1989). © 2010 by the Arizona Board of Regents on behalf of the University of Arizona.
has undertaken a systematic analysis of the isotopic (Sr, Nd, and Pb) compositions and concentrations of a broad compositional range of U.S. Geological Survey (USGS) reference materials, including basalt (BCR-1, 2; BHVO-1, 2), andesite (AGV-1, 2), rhyolite (RGM-1, 2), syenite (STM-1, 2), granodiorite (GSP-2), and granite (G-2, 3). USGS rock reference materials are geochemically well characterized, but there is neither a systematic methodology nor a database for radiogenic isotopic compositions, even for the widely used BCR-1. This investigation represents the first comprehensive, systematic analysis of the isotopic composition and concentration of USGS reference materials and provides an important database for the isotopic community. In addition, the range of equipment at the PCIGR, including a Nu Instruments Plasma MC-ICP-MS, a Thermo Finnigan Triton TIMS, and a Thermo G 3 G 3 Geochemistry Geophysics Geosystems
A method for mapping strontium isotope ratio (Sr-87/(86) Sr) variations in bedrock and water has been recently developed for use in the interpretation of Sr-87/(86) Sr datasets for provenance studies. The mapping process adopted the simplifying assumption that strontium (Sr) comes exclusively from weathering of the underlying bedrock. The scope of this bedrock-only mapping method is thus limited to systems where the contributions of other sources of Sr are minimal. In this paper, we build on this Sr-87/(86) Sr mapping method by developing a mixing model of Sr fluxes from multiple sources to the bioavailable Sr pool. The new multiple source model includes: (1) quantitative calculations of Sr fluxes from bedrock weathering using an empirical rock weathering model; and (2) addition of sub-models calculating the contribution of Sr fluxes from atmospheric aerosols based on outputs from global climate model simulations. We compared the performance of the new multiple source model and the bedrock-only mapping method in predicting observed values from two datasets of bioavailable Sr-87/(86) Sr from the circum-Caribbean region (Antilles and Mesoamerica). Although the bedrock-only method performs relatively well in Mesoamerica (n=99, MAE=0.00011, RMSE=0.00073), its prediction accuracy is lower for the Antillean dataset (n=287, MAE=0.0021, RMSE=0.0027). In comparison, the new multiple source model, which accounts for the deposition of sea salt and mineral dust aerosols, performs comparably well in predicting the observed Sr-87/(86) Sr values in both datasets (MAE=0.00040, RMSE=0.00087 and MAE =0.00014, RMSE=0.0010). This study underscores the potential of using process-oriented spatial modeling to improve the predictive power of Sr isoscapes over large spatial scales and to refine sampling strategies and bioavailable Sr dataset interpretations for provenance studies.
1] We studied soils on high-purity limestones of Quaternary age on the western Atlantic Ocean islands of Barbados, the Florida Keys, and the Bahamas. Potential soil parent materials in this region, external to the carbonate substrate, include volcanic ash from the island of St. Vincent (near Barbados), volcanic ash from the islands of Dominica and St. Lucia (somewhat farther from Barbados), the fine-grained component of distal loess from the lower Mississippi River Valley, and wind-transported dust from Africa. These four parent materials can be differentiated using trace elements (Sc, Cr, Th, and Zr) and rare earth elements that have minimal mobility in the soil-forming environment. Barbados soils have compositions that indicate a complex derivation. Volcanic ash from the island of St. Vincent appears to have been the most important influence, but African dust is a significant contributor, and even Mississippi River valley loess may be a very minor contributor to Barbados soils. Soils on the Florida Keys and islands in the Bahamas appear to have developed mostly from African dust, but Mississippi River valley loess may be a significant contributor. Our results indicate that inputs of African dust are more important to the genesis of soils on islands in the western Atlantic Ocean than previously supposed. We hypothesize that African dust may also be a major contributor to soils on other islands of the Caribbean and to soils in northern South America, central America, Mexico, and the southeastern United States. Dust inputs to subtropical and tropical soils in this region increase both nutrient-holding capacity and nutrient status and thus may be critical in sustaining vegetation.
A spectacular submarine spring is located about 4 km east of Crescent Beach, FL, in the Atlantic Ocean. The single vent feature of Crescent Beach Spring provides a unique opportunity to examine onshore–offshore hydrogeologic processes, as well as point source submarine ground water discharge. The Floridan aquifer system in northeastern Florida consists of Tertiary interspersed limestone and dolomite strata. Impermeable beds confine the water-bearing zones under artesian pressure. Miocene and younger confining strata have been eroded away at the vent feature, enabling direct hydrologic communication of Eocene ground water with coastal bottom waters.
We explore diet and mobility in Middle Archaic Florida using human burials and faunal remains from the Harris Creek archaeological site (8Vo24) on Tick Island. We conducted stable carbon and oxygen isotopic (δ13C, δ18O) analyses of 50 human enamel samples and strontium isotopic (87Sr/86Sr) analysis of a subset of 10. Most individuals (46/50) subsisted on local freshwater and terrestrial resources, with relatively depleted δ13C values (C3) and δ18O values matching those of central and north Florida water resources within the St. Johns River valley. Eight of 10 burials have local, within valley 87Sr/86Sr values. Two human burials yield marine δ13C and 87Sr/86Sr values, which we interpret as evidence for across valley movement from the coast. Another two individuals show depleted δ18O values, likely obtained from northern rivers. We also identified potential food resources and non-local foods from the Harris Creek faunal assemblage. We found six species with estuarine and marine habitat preferences; two of which, whelk and quahog, indicate that people of Harris Creek traveled to or traded with coastal areas.
Waterlogged archaeological sites in Florida contain tools, art objects, dietary items, human skeletal remains, and glimpses of past environments that do not survive the ravages of time at typical terrestrial sites. Unfortunately, archaeological wet sites are invisible since their preservation depends upon their entombment in oxygen-free, organic deposits. As a result, they are often destroyed accidentally during draining, dredging, and development projects. These sites and the objects they contain are an important part of Florida's heritage. They provide an opportunity to learn how the state's earliest residents used available resources to make their lives more comfortable and how they expressed themselves artistically. Without the wood carvings from water-saturated sites, it would be easy to think of early Floridians as culturally impoverished because Florida does not have stone suitable for creating sculptures. This book compiles in one volume detailed accounts of such famous sites as Key Marco, Little Salt Spring, Windover, Ft. Center, and others. The book discusses wet site environments and explains the kinds of physical, chemical, and structural components required to ensure that the proper conditions for site formation are present and prevail through time. The book also talks about how to preserve artifacts that have been entombed in anaerobic deposits and the importance of classes of objects, such as wooden carvings, dietary items, human skeletal remains, to our better understanding of past cultures. Until now this information has been scattered in obscure documents and articles, thus diminishing its importance. Our ancestors may not have been Indians, but they contributed to the state's heritage for more than 10,000 years. Once disturbed by ambitious dredging and draining projects, their story is gone forever; it cannot be transplanted to another location.
The following is a list of radiocarbon dates obtained since the time of the preparation of Michigan list III.∗ The description of the essential features of our method of measurement as given in the introduction to list III applies to this list. The modern standards used were obtained from hardwood logs, and were of various ages from 75 to 150 years by ring count. These standards were sufficiently old so that no correction for the recent dilution of the atmospheric C 14 is believed to be necessary in the dates reported here. The ages of carbonate sample are also calculated from modern wood as a reference standard, without any correction for isotope fractionation.
RATIONALEStrontium isotopes (87Sr/86Sr) are used in archaeological and forensic science as markers of residence or mobility because they reflect the local geological substrate. Currently, tooth enamel is considered to be the most reliable tissue, but it rarely survives heating so that in cremations only calcined bone fragments survive. We set out to test the proposition that calcined bone might prove resistant to diagenesis, given its relatively high crystallinity, as the ability to measure in vivo 87Sr/86Sr from calcined bone would greatly extend application to places and periods in which cremation was the dominant mortuary practice, or where unburned bone and enamel do not survive.METHODS
Tooth enamel and calcined bone samples were exposed to a 87Sr-spiked solution for up to 1 year. Samples were removed after various intervals, and attempts were made to remove the contamination using acetic acid washes and ultrasonication. 87Sr/86Sr was measured before and after pre-treatment on a Nu Plasma multi-collector induced coupled plasma mass spectrometer using NBS987 as a standard.RESULTSThe strontium isotopic ratios of all samples immersed in the spiked solution were strongly modified showing that significant amounts of strontium had been adsorbed or incorporated. After pre-treatment the enamel samples still contained significant amounts of 87Sr-enriched contamination while the calcined bone fragments did not.CONCLUSIONS
The results of the artificial enrichment experiment demonstrate that calcined bone is more resistant to post-mortem exchange than tooth enamel, and that in vivo strontium isotopic ratios are retained in calcined bone. Copyright © 2014 John Wiley & Sons, Ltd.
The first part of the paper describes a multiple-entry card key to coniferous woods. The features employed, which were only selected after extensive investigation, are illustrated and described. Data on over one hundred of the more important tree species of forty genera are given in tabulated form suitable for ready reference and for transference to key cards.In the second part of the paper, the composition, distribution, and wood anatomy of the seven families of Coniferae are briefly dealt with, and under each genus the diagnostic features and methods of identifying the individual species are indicated with particular reference to timber-producing species.Some discrepancies in the existing botanical classification are apparent from this anatomical study.A select bibliography on coniferous wood anatomy is appended, and also a combined index and check-list.
This research addresses the potential contribution of strontium isotopes to the reconstruction of early hominid behavior at the Swartkrans site in the Sterkfontein Valley of Gauteng Provence (formally known as the Transvaal), South Africa. We report that, while there is considerable variability in the 87Sr/86Sr of whole soils within a 15 km radius of this site, available soil and grassland plant 87Sr/86Sr is much less variable and generally above 0.730. This value is higher (more radiogenic) than the 87Sr/86Sr of plants growing within the greenbelt surrounding the Blaaubank stream adjacent to Swartkrans and streamwater itself (0.721).The difference between grassland and riparian strontium isotope composition suggests a method for determining habitat utilization by early hominids. In this study, a geological explanation for a natural difference between Blaaubank stream and grassland Sr is suggested, based on relatively less radiogenic Sr (having lower 87Sr/86Sr values) in the carbonate component of the local dolomite when compared to other nearby geological formations. The explanation was tested initially using a top-down approach in which the 87Sr/86Sr ratios of water, soil, and plants from the entire Blaaubank catchment were measured. Next, a bottom-up approach was used to examine Swartkrans Member I faunal species known to have obtained their Sr from well-defined habitats.The results are that (1) pollution is not the explanation for the relatively low 87Sr/86Sr ratios of the Blaaubank stream, (2) Swartkrans Member I carbonate has a similar 87Sr/86Sr to that of modern Blaaubank water, indicating that relationships seen today existed in the Pleistocene, and (3) Pleistocene riparian fauna have relatively low 87Sr/86Sr ratios when compared to fauna adapted to drier habitats. Together these results make it possible to interpret the strontium isotope composition of Pleistocene early hominids from Swartkrans in terms of habitat utilization.
Perfect counterimages were created when Europeans and American Indians met for the first time in the late 15th century. Unfortunately, historic documents have preserved only one-half of the image. How did the survivors of epidemics, enslavements, and brutalities react to the disruptions in their lives brought about by trespassers from another continent? In this article I examine the historic and archeological evidence for migration into Florida as one of the strategies employed by the displaced people from the Caribbean Islands. The existing records are enhanced by archeological investigations at wet sites, such as Hontoon Island, where surviving biological materials offer information about environment, human skeletons, diet, technologies, and artistic creations in bone and wood that usually perish on dryland sites. At Hoonton Island, water-saturated strata that were not trampled or compressed after deposition revealed that the midden was composed of a prehistoric and an early historic component. The presence of a number of European artifacts led to the conclusion that the extensive changes documented in six of the seven categories of recovered material items resulted either from direct or indirect contact with Europeans or with Indians fleeing the Europeans. New designs on bone objects occur in the early historic period. I attempt to trace the source of one of these designs in an effort to determine the direction of flow for the changes. The use of trait lists to establish relationships is not popular but, in this instance, the investigation of a specific design is enlightening.
In the mantled karst terrane of northern Florida, the water quality of the Upper Floridan aquifer is influenced by the degree of connectivity between the aquifer and the surface. Chemical and isotopic analyses [18O/16O (δ18O), 2H/1H (δD), 13C/12C (δ13C), tritium (3H), and strontium-87/strontium-86 (87Sr/86Sr)] along with geochemical mass-balance modeling were used to identify the dominant hydrochemical processes that control the composition of ground water as it evolves downgradient in two systems. In one system, surface water enters the Upper Floridan aquifer through a sinkhole located in the Northern Highlands physiographic unit. In the other system, surface water enters the aquifer through a sinkhole lake (Lake Bradford) in the Woodville Karst Plain. Differences in the composition of water isotopes (δ18O and <δD) in rainfall, ground water, and surface water were used to develop mixing models of surface water (leakage of water to the Upper Floridan aquifer from a sinkhole lake and a sinkhole) and ground water. Using mass-balance calculations, based on differences in δ18O and δD, the proportion of lake water that mixed with meteoric water ranged from 7 to 86% in water from wells located in close proximity to Lake Bradford. In deeper parts of the Upper Floridan aquifer, water enriched in 18O and D from five of 12 sampled municipal wells indicated that recharge from a sinkhole (1 to 24%) and surface water with an evaporated isotopic signature (2 to 32%) was mixing with ground water.The solute isotopes, δ13C and 87Sr/86Sr, were used to test the sensitivity of binary and ternary mixing models, and to estimate the amount of mass transfer of carbon and other dissolved species in geochemical reactions. In ground water downgradient from Lake Bradford, the dominant processes controlling carbon cycling in ground water were dissolution of carbonate minerals, aerobic degradation of organic matter, and hydrolysis of silicate minerals. In the deeper parts of the Upper Floridan aquifer, the major processes controlling the concentrations of major dissolved species included dissolution of calcite and dolomite, and degradation of organic matter under oxic conditions. The Upper Floridan aquifer is highly susceptible to contamination from activities at the land surface in the Tallahassee area. The presence of post- 1950s concentrations of 3H in ground water from depths greater than 100 m below land surface indicates that water throughout much of the Upper Floridan aquifer has been recharged during the last 40 years. Even though mixing is likely between ground water and surface water in many parts of the study area, the Upper Floridan aquifer produces good quality water, which due to dilution effects shows little if any impact from trace elements or nutrients that are present in surface waters.
A curve describing the variation of the strontium isotopic composition of seawater for the late Neogene (9 to 2 Ma) was constructed from ⁸⁷Sr/⁸⁶Sr analyses of marine carbonate in five Deep Sea Drilling Project (DSDP) sites: 502, 519, 588, 590, and 593. The strontium isotopic composition of the oceans increased between 9 and 2 Ma with several changes in slope. From 9 to 5.5 Ma, ⁸⁷Sr/⁸⁶Sr values were nearly constant at ∼ 0.708925. Between 5.5 and 4.5 Ma, ⁸⁷Sr/⁸⁶Sr ratios increased monotonically at a rate of ∼ 1 × 10⁻⁴ per million years. The steep slope during this interval provides the potential for high resolution strontium isotope stratigraphy across the Miocene/Pliocene boundary. The rate of change of ⁸⁷Sr/⁸⁶Sr decreases to near zero again during the interval 4.5–2.5 Ma, and ratios average 0.709025.
The hydrochemical interaction between groundwater and lakewater influences the composition of water that percolates downward from the surficial aquifer system through the underlying intermediate confining unit and recharges the Upper Floridan aquifer along highlands in Florida. The ⁸⁷Sr/⁸⁶Sr ratio along with the stable isotopes, D, ¹⁸O, and ¹³C were used as tracers to study the interaction between groundwater, lakewater, and aquifer minerals near Lake Barco, a seepage lake in the mantled karst terrane of northern Florida. Upgradient from the lake, the ⁸⁷Sr/⁸⁶Sr ratio of groundwater decreases with depth (mean values of 0.71004, 0.70890, and 0.70852 for water from the surficial aquifer system, intermediate confining unit, and Upper Floridan aquifer, respectively), resulting from the interaction of dilute oxygenated recharge water with aquifer minerals that are less radiogenic with depth. The concentrations of Sr²⁺ generally increase with depth, and higher concentrations of Sr²⁺ in water from the Upper Floridan aquifer (20–35 μg/L), relative to water from the surficial aquifer system and the intermediate confining unit, result from the dissolution of Sr-bearing calcite and dolomite in the Eocene limestone. Dissolution of calcite [δ¹³C= −1.6permil(‰)] is also indicated by an enriched δ¹³CDIC(-8.8 to -11.4 ‰) in water from the Upper Floridan aquifer, relative to the overlying hydrogeologic units (δ¹³CDIC< -16‰).
Sr isotope data from soils, water, and atmospheric inputs in a small tropical granitoid watershed in the Luquillo Mountains of Puerto Rico constrain soil mineral development, weathering fluxes, and atmospheric deposition. This study provides new information on pedogenic processes and geochemical fluxes that is not apparent in watershed mass balances based on major elements alone. 87Sr/86Sr data reveal that Saharan mineral aerosol dust contributes significantly to atmospheric inputs. Watershed-scale Sr isotope mass balance calculations indicate that the dust deposition flux for the watershed is 2100 ± 700 mg cm−2 ka−1. Nd isotope analyses of soil and saprolite samples provide independent evidence for the presence of Saharan dust in the regolith. Watershed-scale Sr isotope mass balance calculations are used to calculate the overall short-term chemical denudation velocity for the watershed, which agrees well with previous denudation rate estimates based on major element chemistry and cosmogenic nuclides. The dissolved streamwater Sr flux is dominated by weathering of plagioclase and hornblende and partial weathering of biotite in the saprock zone. A steep gradient in regolith porewater 87Sr/86Sr ratio with depth, from 0.70635 to as high as 0.71395, reflects the transition from primary mineral-derived Sr to a combination of residual biotite-derived Sr and atmospherically-derived Sr near the surface, and allows multiple origins of kaolinite to be identified.
The cupric oxide oxidation products of 23 vascular and nonvascular plant tissues have been measured. Compositional data for vanillyl, syringyl, and cinnamyl phenols are presented in the form of five lignin parameters which are related to plant variety, lignin concentration, and tissue type. On the basis of these parameters, the 23 plant tissue samples are resolved into distinct compositional regions corresponding to: 1.(a) nonvascular plants,2.(b) gymnosperm woods,3.(c) non woody gymnosperm tissues,4.(d) angiosperm woods, and5.(e) nonwoody angiosperm tissues. The same five parameters also can be determined for organic materials in soils and sediments and used either to discriminate between compositionally different organic mixtures or to estimate the relative amounts of each of the above types of plant materials in the deposits.
The strontium (Sr) isotope method can be a powerful tool in studies of chemical weathering and soil genesis, cation provenance and mobility, and the chronostratigraphic correlation of marine sediments. It is a sensitive geochemical tracer, applicable to large-scale ecosystem studies as well as to centimeter-scaled examination of cation mobility within a soil profile. The 87Sr/86Sr ratios of natural materials reflect the sources of strontium available during their formation. Isotopically distinct inputs from precipitation, dryfall, soil parent material, and surface or groundwater allow determination of the relative proportions of those materials entering or leaving an ecosystem. The isotopic compositions of labile (soil exchange complex and soil solution) strontium and Sr in vegetation reflect the sources of cations available to plants. Strontium isotopes can be used to track the biogeochemical cycling of nutrient cations such as calcium. The extent of cation contributions from in situ weathering and external additions to soil from dust and rain can also be resolved with this method. In this paper, we review the geochemistry and isotopic systematics of strontium, and discuss the use of this method as a tracer of earth surface processes.
The increasing acidification and impoverishment of soil poses a great environmental problem today and in the future and is exemplified by the decreased availability of calcium in the soil pool. Unfortunately, budgeting the inputs and outputs of calcium in the soil-vegetation ecosystem is a very laborious task. Some of the fluxes are internal in the ecosystem and cannot be measured explicitely, like weathering of primary minerals. However, since strontium and calcium exhibit similar geochemical behaviour, it is possible to make an estimation of the calcium content in different media in the soil-vegetation eco-system using natural strontium isotopes. Preliminary analyses of water (precipitation, throughfall, runoff, soil-water), soil (mineral matter) and biological material (trees, mussel-shells) show that the use of the strontium isotope ratio 87Sr/86Sr is a powerful tool in estimating and understanding environmental changes.
Most previous workers have regarded the insoluble residues of high-purity Quaternary limestones (coral reefs and oolites) as the most important parent material for well-developed, clay-rich soils on Caribbean and western Atlantic islands, but this genetic mechanism requires unreasonable amounts of limestone solution in Quaternary time. Other possible parent materials from external sources are volcanic ash from the Lesser Antilles island arc and Saharan dust carried across the Atlantic Ocean on the northeast trade winds. Soils on Quaternary coral terraces and carbonate eolianites on Barbados, Jamaica, the Florida Keys (United States), and New Providence Island (Bahamas) were studied to determine which, if either, external source was important. Caribbean volcanic ashes and Saharan dust can be clearly distinguished using ratios of relatively immobile elements (). Comparison of these ratios in 25 soils, where estimated ages range from 125,000 to about 870,000 yr, shows that Saharan dust is the most important parent material for soils on all islands. These results indicate that the northeast trade winds have been an important component of the regional climatology for much of the Quaterary. Saharan dust may also be an important parent material for Caribbean island bauxites of much greater age.
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