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The study of Paleolithic archaeology in China has flourished over the last two decades, providing a unique perspective on the development of human culture and emergence of modern Homo. This dissertation is a comparative study of two Upper Pleistocene sites in North China: the site of Salawusu, in Inner Mongolia and the Shiyu site in northern Shanxi province. Lithic assemblages from both sites have been assigned to the broad category of "small tool tradition" as defined by contemporary Paleolithic archaeologists in China. This study addresses the nature of the variability within this tool tradition as it relates to reduction strategies, the organization of prehistoric technology and the role that resource type and availability played in this organization. A critical discussion of the radiocarbon dates for these sites and a correlation of the stratigraphy with the Oxygen Isotope chronology and paleoenvironmental evidence, suggests that these sites are separated by a much greater temporal span than their radiocarbon dates have indicated. The interpretation of the Salawusu section proposed in this study correlates the cultural materials recovered in the 1980 excavations with δ¹⁸O Stage 5 while the Shiyu remains are correlated with δ¹⁸O Stage 2. The lithic analysis documents quantitative and qualitative differences between these artifact assemblages which also call into question the closeness of their relationship. The Shiyu lithics are a homogeneous collection dominated by elongated flakes, blades, points and implements fashioned on these. The Salawusu assemblage is less standardized and shows no trend toward flake elongation or blade technology.

<p> Modern and fossil ecological data exist at very different taxonomic, spatial, and temporal scales. For modern ecology, data are typically collected at the species-level, cover square meter quadrats to the entire globe, and span days to decades at most. For fossil assemblages, spatial scale might be comparable to that studied by modern ecologists, but fossil data are taxonomically and temporally much coarser (respectively, order-, family-, genus-level at best, and 104-108 years). Recent research has shown that ecological patterns and the processes affecting them change across scale. Therefore, using modern ecological theory and methods to study fossil data is an incommensurate exercise and potentially produces spurious results. Moreover, scale varies by orders of magnitude even among fossil assemblages, so comparing fossil sites without an appreciation of scale may also lead to ambiguous conclusions. </p><p> I argue that a disregard of scale within paleoanthropology has contributed to its inability to synthesize seemingly disparate paleoecological results into a coherent, unified framework. As a result, paleoanthropology has remained relatively stagnant regarding its understanding of how paleoecological processes drove hominin evolution. With this in mind, I adopt scale as a central theme in my dissertation and attempt to understand how ecological pattern and process change across modern and fossil scales in East African large mammal communities, and if these scale differences can be analytically reconciled. </p><p> The results from my three research chapters show ecological patterns (and the relevant processes driving them) fundamentally change across modern and fossil scales. Thus, modern and paleoecological theory and data are each incomplete: modern ecologists need to analyze fossil data if they want to study ecology at large time scales, and paleoecologists need to examine modern data and theory in order to understand smaller-scale processes; simple extrapolation and interpolation will not do. For paleoanthropologists, that means it is less than straightforward to infer smaller-scale ecological processes (e.g., paleoenvironmental reconstruction, interspecific interactions) from fossil assemblages, and caution should be exercised when attempting to do so. I by no means offer a panacea for this scale issue, but hopefully my research will make paleoanthropologists more cognizant of scale and encourage future research on this topic. Only then can we finally begin to understand what exactly were the important ecological drivers affecting hominin behavior and evolution. </p>

The human colonization of Beringia during the Late Glacial (14,500-11,700 years ago) is one of the most remarkable events in human history, as people coming from northeastern Eurasia permanently settled the subarctic for the first time and opened the way for the initial colonization of the New World, coincident with the extinction of mammalian megafauna. This dissertation uses an interdisciplinary methodological and theoretical framework to investigate the trophic ecology of past Beringian hunter-gatherers, their place in predator guilds and in the broader mammal community. Methods of study include faunal and spatial analyses of existing archaeological collections, analyzing the function of the sites as well as their spatial relationship to resources, and documenting new sites in the region through excavations. In support of the archaeological work I conducted isotopic analyses (δ13C and δ15N) of fossil megafauna from contemporaneous paleontological and archaeological sites in order to study habitat partitioning within the herbivore and predator guilds. Results show that resources targeted by early Beringian people were concentrated in high biomass patches and that people exploited these patches through highly specialized, logistical sites. Specifically, the occupation at Swan Point CZ4b is interpreted as a specialized workshop dedicated to the production and maintenance of organic-based tools, providing evidence that Beringian people relied on animals not only for food but also to a large extent for technological purposes. Isotopic data suggest that Beringian people are unlikely to have had profound negative effects on populations of large herbivores through their economic choices. On the other hand, humans do seem to have contributed to the extinction of Beringian large carnivores by competing with and ultimately displacing them at high trophic levels. This dissertation provides new evidence of the impact that the integration of early Beringian people within predator communities had on material culture and economy as well as on larger-scale ecosystem processes.

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

The Hudson River estuary (New York, USA) is a heavily urbanized estuary with a long history of environmental impacts from anthropogenic activities for hundreds of years. The estuary is intensely utilized, serving over ten million people throughout New York, Connecticut, and New Jersey. The portion of the Hudson River from Troy, NY to New York Harbor is tidal and is considered an important estuary. Tidal marshes are especially important for their roles in carbon sequestration, water filtration, primary production, flood-zone buffering, fisheries, and recreation. However, these valuable ecosystems are threatened by increasing anthropogenic activities, such as land clearing, channel modification, contamination release, and the introduction of invasive species (Howarth et al. 1991, Swaney et al. 1996, Pederson et al. 2005, Miller et al. 2006, Wall et al. 2008, Chou and Peteet. 2010, Nguyen and Peteet 2010, Collins and Miller 2011). In addition, projected warming, drought, sea level rise, and salt intrusion will likely amplify these anthropogenic effects (Bindoff et al. 2007, Christensen et al. 2007). Vegetation and sediment composition are two major keys that determine the health of the ecosystem. Thus, a necessary key in the restoration of the estuary is the understanding of baseline ecosystem and sedimental conditions as well as their long-term responses to climatic and anthropogenic activities. Such information is limited in the Hudson estuary (NYSDEC 2006, 2009, 2012). In this dissertation, we establish the baseline conditions of the vegetation and sediments of the Hudson Estuary using sediment cores from marshes and tributaries of the Hudson Estuary and investigate how the ecosystems have changed over time in response to major environmental changes. We expand paleoecological records in the freshwater section of the estuary to understand regional ecological changes as prior studies are restricted to the lower portion of the Hudson. An estuary-wide study of wetland and delta sediments across various environmental regimes aids our understanding of regional environmental shifts. We used two approaches to investigate environmental changes of the Hudson Estuary: 1) Long-term multiproxy paleoecological reconstruction at two important freshwater National Estuarine Research Reserve marshes; and 2) pre and post industrialization sediment composition analysis across a North-South transect of the river. Knowledge about past ecosystem structure and ecosystem response to anthropogenic and climatic changes can provide insights on how future changes may impact the ecosystem. Such information may be useful in future environmental management (Jackson and Hobbs 2009). In the first two chapters, we implement multiple proxies, including pollen, spores, macrofossils, charcoal, sediment bulk chemistry, and stable carbon and nitrogen isotopes to identify ecosystem changes spanning the past 1000 years in Tivoli Bays and Stockport Flats. Paleoecological reconstruction at both of these sites reveal climatic shifts such as the warm and dry Medieval Warm Period (MWP, 800 - 1300 AD) with high fire occurrence followed by the wetter cooler Little Ice Age (LIA, 1400 - 1800 AD), along with significant anthropogenic alterations in the watershed. Wetland and upland vegetation slightly changed during that period, reflecting water availability and temperature. The most striking changes occurred after the European settlement in the 17th - 18th centuries. Throughout the last century, invasive plant species including Typha angustifolia, Phragmites australis, and Lythrum salicaria pollen percentages increased by up to 20 times the pre-European settlement values, concurrent with marked changes in sedimentation rate, sediment composition, nutrient input, and organic content. Isotopic analysis of 13C at Tivoli Bays confirms major vegetation shifts concurrent with European settlement. The increase of fertilizer and sewage water was also visible by the enrichment of 15N in the sediment at the onset of European settlement. The concurrent trend of vegetation and sediment compositional changes suggests that sediment dynamics may play an important role in shaping wetland characteristics. In Chapter 2, the paleoecological result at Stockport Flats shows similar adverse anthropogenic impacts to the wetland as the biggest vegetation changes occurred at the onset of European settlement. In contrast to Tivoli, Stockport was a mudflat prior to the European settlement. As a result, Stockport has lower organic matter content (measured as Loss-On-Ignition (LOI)), less peat accumulation, and coarser grain size than Tivoli. This raises a question about what type of habitat should be targeted for conservation. A recently colonized wetland such as Stockport Flats does not serve the same function in carbon storage as an older wetland such as Tivoli. The third chapter is the first estuary-wide study of Hudson River sediment composition and sediment change before and after significant anthropogenic impacts. We characterize sediment composition at 20 wetlands and deltas across various environmental regimes from Troy, NY to the mouth of the Hudson River in New York Harbor. We identify natural and anthropogenic control of sediment dynamics in the estuary. Prior to the industrialization, LOI in older wetlands (24 % on average) is significantly higher than in new marshes and deltas (10% on average), indicating the importance of old wetlands as carbon sinks. After the European settlement, LOI markedly decreased and K, Ti, Rb, and Zr significantly increased in old wetlands as a result of the increase in land erosion and channel modification. Pb, Zn, Cu and Cr were found to be more enriched in relation to Sr than the upper continental crustal value by up to 180, 320, 100, and 18 times respectively as a result of anthropogenic input. During the process of correcting the signal for background metal level, we also found that the sediments from various settings have a wide range of background Pb of 8 - 80 ppm. Thus, the crustal Pb values that are commonly used for background correction of 20 - 25 ppm are not always applicable and detailed analysis of the actual background concentration at each location is necessary in order to accurately estimate anthropogenic contributions of industrial metals. Based on ecological and chemical proxies, we observe an enormous magnitude of change in vegetation, sedimentation rate, organic matter content, and nutrients during the last few centuries in the Hudson estuary, indicating significant anthropogenic influence on wetlands. Our estuary-wide sediment study indicates significant regional landscape change which results in an increase in inorganic matter input concurrent with vegetational shifts. The characterization of the baseline ecology and sediments in this study provides a guideline for ecosystem restoration and management to target the recovery and conservation of vegetation and sediment composition that is the most suitable for a given environment to fully reinstate ecosystem structure and function.

The Flanner Beach Formation was deposited along the Atlantic Coast of North Carolina, during a high stand of sea level about 200,000 years BP. The formation consists of three members in the Neuse River valley: (1) Smith Gut member (new unit), deposited in early transgressive, open bay settings; (2) Arapahoe sand member, deposited in barrier island environments as rate of sea level rise decreased; and (3) Beard Creek member, composed of bay and lagoonal sediments that accumulated in varied estuarine settings landward of the Arapahoe barrier. Time-equivalent deposits along the Pamlico River also consist of three members: (1) Hills Point member (new unit), deposited in restricted lagoonal or river estuary settings; (2) Mauls Point member (new unit), deposited in open lagoonal areas; and (3) an unnamed member resembling the Beard Creek Paleoecologic units identified in the Smith Gut and Beard Creek members included, in ascending stratigraphic order: (1) polyhaline, open bay fossil associations; (2) polyhaline, slightly restricted bay associations; (3) mesohaline, restricted lagoonal associations; (4) polyhaline, open lagoonal associations; and (5) a mesohaline (?), firm-ground association. The sequence of mollusk-dominated associations reflects changes in composition and structure of intergrading, soft-bottom communities that responded to gradual alterations in water circulation patterns, salinity, intensity of seasonal environmental rigor, and to a lesser extent slight changes in bathymetry and substrate properties, during the evolution of a major barrier-lagoon system. This long-period change in benthic communities is an example of gradual community replacement--the substitution of one community of organisms for another in space and time owing to gradual changes in environmental contexts, yielding a sequence of fossil associations each with slightly different paleosynecologic attributes Gradual replacement is dominated by processes of reorganization of species-abundance patterns, with faunal turnover playing a relatively minor role. In rapidly changing environments, turnover is the dominant mechanism of replacement. Reorganization appears to involve the following processes in estuarine benthic communities: (1) changes in numerical importance of superdominant taxa; (2) shifts in rank levels of subdominant taxa; (3) large changes in rank levels of numerically minor taxa; and (4) gradual demotion of certain taxa to lower rank levels through the preserved community sequence. Simple additions and deletions of minor faunal elements also can occur / acase@tulane.edu

Abstract not available