@mastersthesis {476, title = {Deciphering arctic climate in a past greenhouse world: Multiproxy reconstructions of pliocene climate}, volume = {PhD}, year = {2011}, school = {University of Arizona}, abstract = {

The high sensitivity of high latitudes to global climate changes is the stimulus for the study of ancient Arctic ecosystems under greenhouse conditions. With an increasing number of studies, including the most recent Intergovernmental Panel on Climate Change (IPCC) report highlighting Pliocene climate as key example for the study of Earth system sensitivity to higher levels of atmospheric CO$_{2}$ , the need for accurate proxy records for this period is crucial. In order to investigate Pliocene climate, I used stable isotopic studies of fossil molluscs, moss and wood from two fossil forest deposits in the Canadian High Arctic. Temperatures were determined for an Early Pliocene (4-5 Ma) fossil forest site located on Ellesmere Island using \‘clumped\’ and stable isotopic analysis of mollusc shells and stable isotope values of fossil wood. Mollusc inferred growing season (May-Sept) temperatures derived using two independent techniques were estimated to be 11-16\°C warmer than present (1950-1990) Ellesmere Island temperatures. Tree ring inferred growing season (June-July) temperatures (JJ) were 10-16\°C and mean annual temperatures (MAT) were 18-20\°C warmer than present (1950-1990). Mean annual and growing season (JJ) temperatures were also determined using fossil wood from a younger (2.4-2.8 Ma) late Pliocene-early Pleistocene site on Bylot Island. This deposit represents the remains of a flora that grew during an interglacial warm period during the transition to large-scale Northern Hemisphere glaciation that occurred between 2.5 to 3 million years ago. Mean annual temperatures were \∼12\° C and growing season temperatures were \∼13\°C warmer than present (1923-2010). The interglacial setting of the Bylot Island site and the warm temperatures suggests that prior to using such sites as true analogues of future conditions we may need to consider how close the feedbacks operating then were to the feedbacks we might expect in the future. However, that temperatures so much warmer than present existed in the high Arctic during a period when levels of atmospheric CO$_{2}$ were at nearpresent levels indicates that we may be moving beyond our ability to use the Pliocene as an example of the future.

}, keywords = {Paleoclimate Science}, author = {Csank, Adam Zoltan} } @mastersthesis {464, title = {Elevated atmospheric carbon dioxide impacts carbon dynamics in a C(4)-sorghum-soil agroecosystem: An application of stable carbon isotopes (delta carbon-13) in tracing the fate of carbon in the atmosphere-plant-soil ecosystem}, volume = {PhD}, year = {2005}, school = {University of Arizona}, abstract = {Although a strong inter-dependence exists between atmospheric carbon dioxide (CO$_{2}$) and the terrestrial carbon (C) cycle, the response of plant-soil ecosystems to the rapid increase in atmospheric CO$_{2}$ is not well understood. My dissertation research focused on the impacts of elevated CO$_{2}$ on the carbon dynamics of plant-soil ecosystems, which were a major part of the overall C$_{4}$-sorghum Free-Air CO$_{2}$ Enrichment (FACE) experiment conducted by the University of Arizona and USDA at the Maricopa Agriculture Center, Arizona, USA, in 1998 and 1999. In the experiment, sorghum (Sorghum bicolor (L) Moench) crop was exposed to elevated CO$_{2}$ ({\textquotedblleft}FACE{\textquotedblright}: ca. 560 {\textmu}mol mol$^{-}${\textonesuperior}) and ambient CO$_{2}$ ({\textquotedblleft}Control{\textquotedblright}: ca. 360 {\textmu}mol mol$^{-}${\textonesuperior}) interacting with well-watered and water-stressed treatments. The results from my study showed that the seasonal mean soil respiration rate measured in elevated CO$_{2}$ plots over two growing seasons was 3.3 {\textmu}mol m$^{-}${\texttwosuperior}s$^{-}${\textonesuperior}, i.e., 12.7\% higher than the 2.9 {\textmu}mol m$^{-}${\texttwosuperior}s$^{-}${\textonesuperior}in ambient CO$_{2}$ plots. The increased respiration mainly resulted from the stimulated root respiration under elevated CO$_{2}$, which increased 36.1\% compared to that under ambient CO$_{2}$. Measured changes in sorghum residue biochemistry caused by CO$_{2}$ were detected, with decrease of amino acids and hemicellulose carbohydrates by 7\% and 8\%, respectively, and increase of cellulose carbohydrates and lignin by 49\% and 5\%, respectively. Phenolics were only significantly higher in FACE roots. The C:N ratio of sorghum tissues was not affected by elevated CO$_{2}$, but was substantially lower under water stress. The laboratory incubation showed that an average of 7.3\% significantly less respired CO$_{2}$ was released from the FACE-tissue-amended soil than the Control-tissues-amended soil over the full 79-d incubation period. Non-lignin phenolics (r{\texttwosuperior} = 0.93, p = 0.002), and lignin (r{\texttwosuperior} = 0.89, p = 0.004) were found to be the most important factors related to the sorghum tissue decomposition. Highly stable residues of FACE sorghum input to the soil resulted in the increase of the recalcitrant C pool and the decrease of the labile C pool. As a result, mean residence time of SOC in FACE field plot increased compared to that in Control plot, suggesting that the SOC under elevated CO$_{2}$ was more stable against decomposition.}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=885700691\&sid=10\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Cheng, Li} } @mastersthesis {649, title = {Archaeomagnetic research in the United States midcontinent}, volume = {PhD}, year = {2004}, school = {University of Arizona}, abstract = {This dissertation combines archaeomagnetic and independent chronometric data from 240 archaeological features to develop a regional secular variation curve for the U.S. midcontinent. These data were obtained from features located between 31.5-40.5{\textdegree} N latitude and 82.5-93.5{\textdegree} W longitude that have been dated to between 60 and 10,700 cal BP. The archaeomagnetic samples were collected from 41 sites within this region over the past 35 years under the direction of four different researchers: Robert DuBois (University of Oklahoma), Daniel Wolfman (University of Arkansas and New Mexico State Museum), Wulf Gose (University of Texas at Austin), and myself. In this project, the data are initially smoothed through the moving windows method to form the first approximation of the curve. Outlier analyses and pairwise statistical comparisons are utilized to refine the smoothed curve, and the results are compared to other Holocene-aged secular variation records from North America. These analyses indicate that the final curve should be treated as three distinct segments with different precision and use recommendations. First, the 850-75 cal BP segment can be used to date archaeomagnetic sample from the project area with expected temporal precision of 100-200 years. Second, the 2528-850 cal BP segment can be used cautiously to date archaeomagnetic samples with an expected temporal precision of 200-300 years. Third, the 9755-4650 cal BP segment should be used for contextual dating purposes only, in that an undated sample can be put into a regional context through comparison with the segment{\textquoteright}s constituent samples. Finally, three archaeological problems are addressed through the archaeomagnetic data. First, archaeomagnetic data are used to resolve the temporal conflict between an eastern Tennessee structure{\textquoteright}s morphology and a much earlier radiocarbon date obtained for the structure. Then, archaeomagnetic data are used to address a number of internal chronology questions regarding three Powers phase sites in eastern Missouri. Finally, the sequencing of several protohistoric and historic sites in eastern Tennessee is examined through a series of archaeomagnetic data. }, keywords = {Archaeomagnetic research, Chronometrics, Midcontinent, Missouri, Tennessee}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=765928991\&sid=6\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Stacey Lengyel} } @mastersthesis {652, title = {A comparative study of soil disturbance from uprooted trees, and mound and pit decay in Puerto Rico and Colorado}, volume = {PhD}, year = {2003}, school = {University of Arizona}, abstract = {The toppling of trees forms mounds of disturbed sediment and pits from which the mound removes sediment, rocks, and organic matter. Sites of uprooted trees in Puerto Rico and Colorado were examined (1) to compare areas and volumes of mounds and pits relative to tree size, (2) to compare areas and volumes of mounds and pits formed during catastrophic events at the landscape scale, and (3) to consider decay of mounds and pits after formation. For a given basal area, the analyses found no difference among sites in area and volume of freshly formed individual mounds and pits. For landscape-level catastrophic uprooting, the percent of toppled trees in a plot can explain 85\% and 87\% of the areas and volumes, respectively, of the quantity of soil uplifted. Exponential decay coefficients developed by monitoring mound/pit complexes indicate that mounds and pits at the humid tropical site in Puerto Rico decay in about 74\% and 57\% of the time, respectively, of mounds and pits at a temperate Colorado site. Decay coefficients developed for the Colorado site indicate that mounds and pits are reduced to 10\% of their original volume within 30 and 78 years, respectively. Coefficients for Puerto Rico suggest that a similar reduction in volume requires 17 years, whereas pits generally fill within a decade.}, keywords = {colorado, Mound and pit, Puerto Rico, Soil disturbance, Uprooted}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=765017541\&sid=9\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Melanie Lenart} } @mastersthesis {591, title = {Delta-deuterium and delta-oxygen-18 in mixed conifer systems in the United States southwest: The potential of delta-oxygen-18 in Pinus ponderosa tree rings as a natural environmental recorder}, volume = {PhD}, year = {2001}, school = {University of Arizona}, abstract = {The North American Monsoon provides half of the annual precipitation in Tucson, Arizona. The other half occurs dominantly during the winter and early spring. Late spring is the transitional period to the monsoon and is characterized by high temperatures and low humidity. The reliability of this hyperarid period, the consistency of the timing of monsoon onset, and the recognition that certain high-elevation trees produce annual false latewood bands in response to this transitional period, were critical to the design of this dissertation research. I hypothesized that subannual environmental signals might be fixed in stable oxygen isotopes in cellulose from such trees. Existence of a long-term dataset of δD and δ 18 O from Tucson precipitation provided impetus for the collection of a companion dataset at a high-elevation site in the Santa Catalina Mountains north of Tucson. Trees were sampled near the precipitation collection site. The relations between the stable isotope ratios in the precipitation and in the tree cellulose were identified through extraction of water from bimonthly samples of nearby soil, tree stems and needles. Spatial consistency of the cellulose stable isotope signals was measured using tree samples from seven additional sites across the U.S. desert Southwest. Correlations between Tucson summer precipitation δ 18 O and both local and extra-regional environmental parameters resulted in the identification of the dominant monsoonal moisture source for the Tucson area. Similar correlations with the cellulose δ 18 O timeseries from the post-false latewood cellulose, supported the previous interpretations, and suggest long-term reconstructions may be possible. Correlations between the earliest cellulose δ 18 O division and extra-regional environmental parameters suggest environmental measures may be reconstructable for the cool season. Comparison of the high and low elevation precipitation δD and δ 18 O datasets yielded many baseline measures of precipitation stable-isotope dynamics in the U.S. desert Southwest. Comparison of the high-elevation precipitation stable isotope record with soil and stem water δD and δ 18 O from nearby confirmed that local trees were using dominantly deeper soil water. I noted correlations between measured needle-water stable isotope values and values calculated using a leaf-water model, but systematic departures suggest an additional unmodeled process may operate in this system.}, keywords = {Geochemistry}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=728996441\&sid=11\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Wright, William Edward} } @mastersthesis {655, title = {Winslow Orange Ware and the ancestral Hopi migration horizon}, volume = {Phd}, year = {2001}, school = {University of Arizona}, abstract = {This project involved instrumental neutron activation analysis of 428 ceramic vessels and clays, typological analysis of 1135 vessels, and stylistic analysis of more than 400 bowls. Most of the items analyzed were recovered from the Homol{\textquoteright}ovi villages, a group of eight Pueblo III-Pueblo IV (circa A.D. 1250-1400) sites located near Winslow, Arizona. These studies were conducted in order to address the question of the origin(s), geographically speaking, of the ancient inhabitants of the Homol{\textquoteright}ovi villages. The results of the compositional analysis indicate local production of Winslow Orange Ware at Homol{\textquoteright}ovi and in the Petrified Forest. Circulation of Winslow Orange Ware to the Anderson Mesa area, the Tonto Basin, and the Verde Valley is also evident. Furthermore, among the earliest ceramic assemblages from the Homol{\textquoteright}ovi sites were found locally-produced versions of ancestral Hopi pottery types and vessel forms. The compositional data also point to local production of Roosevelt Red Ware at Homol{\textquoteright}ovi and in the Petrified Forest. The whole vessel study resulted in the observation that most Winslow Orange Ware vessels represent attempts to produce Jeddito Orange Ware using materials indigenous to the Middle Little Colorado River Valley. An examination of the dating and distribution of different kiva forms revealed that Homol{\textquoteright}ovi ceremonial architecture reflects western Kayenta and Tusayan patterns, supporting the ceramic-based inference of ancestral Hopi migration. Placing these results in broader context, it is possible to discern an ancestral Hopi migration horizon which corresponds with what has been called the Salado archaeological culture or the "Salado phenomenon." By examining Hopi oral texts, it was observed that many include information that correlates with archaeological and anthropological models of Hopi origins. By hypothesizing that these accounts represent significantly restructured texts, it is possible to resolve apparent disconformities between Hopi oral tradition and anthropological inferences. This conception of Hopi migration accounts allows resolution of conflicting interpretations of Homol{\textquoteright}ovi, i.e., the idea that it is an ancestral Hopi place because its inhabitants moved to the Hopi Mesas circa A.D. 1400, versus the notion that it is an ancestral Hopi place because its inhabitants were immigrants from the Hopi Mesas. }, keywords = {Ancestral, Arizona, Hopi, Migration, Winslow Orange Ware}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=729042861\&sid=14\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Patrick Lyons} } @mastersthesis {723, title = {Simulating the Long House Valley: An evaluation of the role of agent-based computer simulation in archaeology}, volume = {M.A.}, year = {1998}, school = {University of Arizona}, abstract = {This study presents the results of a detailed analysis of an agent-based computer simulation called Artificial Anasazi. The simulation attempts to replicate the population growth and settlement patterns of the prehistoric Kayenta Anasazi of Long House Valley in northeastern Arizona between A.D. 400-1300. Agent-based simulations model social evolution from the bottom-up, using heterogeneous agents that follow simple rules, in contrast to the top-down computer simulations usually used by archaeologists. Artificial Anasazi is tested against the archaeological record of the real Long House Valley through both qualitative and quantitative methods, and an analysis of the relevant ethnographic information is presented. The ultimate goal of this study is to elucidate the potentials and pitfalls of using agent-based computer simulation as a serious research tool in archaeology.}, keywords = {Arizona}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=734127421\&sid=51\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Matthew Littler} } @mastersthesis {549, title = {Precipitation seasonality recorded in D/H ratios of pinyon pine cellulose in the southwestern United States}, volume = {PhD}, year = {1997}, school = {University of Arizona}, abstract = {I assessed the paleoclimatic significance of $\delta$D values of pinon pine (Pinus edulis and P. monoyhylla) cellulose nitrate (cn) by developing, testing and applying deterministic and empirical models, in the context of the soil-plant-atmosphere continuum. Stable isotope values of precipitation, soil water, xylem sap, leaf water, atmospheric vapor, annual and sub-annual samples of tree-ring and needle cellulose, and climatic parameters, were measured along, a gradient of decreasing summer rain in the southwestern U.S. Stable isotope composition of sap indicated depth of moisture extraction. Over the growing season in New Mexico and Arizona, where monsoon rains are important, trees shifted their water use to shallower depths. In Nevada, where summer rain is scarce, trees shifted to deeper moisture late in the growing season. Evaporation altered $\delta$D and $\delta\sp{18}$O values of precipitation inputs to soil. Only after heavy monsoons did soil water and sap isotopically resemble recent precipitation. Average precipitation $\delta$D values set the baseline for $\rm\delta D\sb{cn}$ values at each site, but interannual variations in relative humidity and precipitation amount altered wood and leaf $\rm\delta D\sb{cn}$ values, via leaf water effects. Leaf water (lw) was evaporatively enriched by seasonal moisture stress. $\rm\delta D\sb{lw}$ and $\rm\delta\sp{18}O\sb{lw}$ values were strongly correlated with relative humidity on a seasonal basis, but not on a diurnal basis. Measured $\rm\delta\sp{18}O\sb{lw}$ values fit a steady-state model, with an offset attributable to relative humidity. Measured $\rm\delta D\sb{lw}$ values were more depleted than predicted by the model, suggesting leaf water-organic matter isotopic exchange. Biochemical fractionation $\rm(\epsilon\sb{B})$ of hydrogen isotopes between leaf water and cellulose was inversely correlated with relative humidity. Empirical models based on linear regressions demonstrated significant correlations between $\rm\delta D\sb{cn}$ values and precipitation seasonality. An El Nino-Southern Oscillation signal (wood $\rm\delta D\sb{cn}$ values inversely related to winter precipitation amount) was found in New Mexico and Arizona. A summer rain signal (leaf $\rm\delta D\sb{cn}$ values inversely related to summer humidity) was found at all sites. $\rm\delta D\sb{cn}$ values of pinon needles in packrat middens from Sevilleta LTER, New Mexico, suggest that late Pleistocene summers were as wet as today{\textquoteright}s, and/or that storm tracks could have shifted, bringing in more tropical moisture than currently.}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=736806701\&sid=12\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Pendall, Elise Gislaine} } @mastersthesis {660, title = {Patterns and processes of treeline forest response to late Holocene climate change in the Sierra Nevada, California}, volume = {Phd}, year = {1996}, school = {University of Arizona}, abstract = {Climate variation that occurred during the late Holocene left a visible imprint on the Sierra Nevadan landscape. Dead trees rooted above the current treeline testify to the dynamic history of subalpine forests, while seedlings established above treeline in recent decades hint at ongoing change. I used a combination of modern studies of tree growth and retrospective studies of forest population dynamics and treeline history to investigate the patterns and processes of subalpine forest response to late Holocene climate variation in the Sierra Nevada. Seedling apical growth increased with elevation, suggesting that local-scale microclimatic gradients, perhaps in combination with changes in resource availability, were a more important control over growth than are coarse-scale features of climate. The retrospective analysis of past population dynamics indicated that recruitment was more sensitive to climate variation than mortality. Recruitment was inversely correlated with temperature; mortality exceeded recruitment during warm, dry episodes, whereas recruitment exceeded mortality during cold, wet episodes. Mortality was uncorrelated with climate, except in the most marginal locations. Life history traits (extreme longevity, long reproductive life span) may impart inertia to treeline forests: population demise has not occurred in the past 3,500 years without increased adult mortality. Treeline elevation was higher than present for most of the last 3,500 years. Tree abundance and treeline elevation declined between A.D./B.C. and A.D. 400, A.D. 1000 and A.D. 1400, and after A.D. 1500. Treeline elevation and tree abundance increased at 2 sites from A.D. 400 to A.D. 700. Both moisture and precipitation appear to be important controls over population processes at treeline. Contraction of subalpine forests was associated with cold and warm/dry conditions, and the expansion of subalpine forests was associated with warm conditions. Treeline response to temperature can apparently be modified by water availability, which can invert treeline response to temperature, causing treeline to decline during warm periods. The most marginal populations, within 30 m of treeline, are sensitive to decadal to centennial-scale climate conditions. Non-marginal populations are generally insensitive to climate, and are likely buffered both by life history and by their position relative to the forest border.}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=742626921\&sid=20\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Andrea Lloyd} } @mastersthesis {526, title = {Agroclimate, Harvest Variability, and Agricultural Strategies on Prehistoric Black Mesa, Northeasthern Arizona}, volume = {PhD}, year = {1991}, school = {Indiana University}, author = {Lebo, Cathy J.} } @mastersthesis {523, title = {The Dynamics and Disturbance Regimes of Fitzroya cupressoides Forests in the South-Central Andes of Chile}, volume = {PhD}, year = {1991}, school = {University of Chile}, author = {Lara, Antonio} } @mastersthesis {700, title = {The structure and function of the prehistoric household in the pueblo southwest: A case study from Turkey Creek Pueblo}, volume = {PhD}, year = {1986}, school = {University of Arizona}, abstract = {The Pueblo household in the American Southwest is examined at Hopi and Zuni and at the prehistoric pueblo of Turkey Creek. Cultural, economic, and environmental factors that influence household organization and function crossculturally are identified and organized into a framework suitable for investigation of households in the archaeological record. Early Hopi and Zuni ethnographic material is reorganized within the research framework thus established. The arrangement of activities in space by social unit is discussed and tabulated to serve as a convenient reference for archaeologists. This research framework directs examination of household dynamics in a unique prehistoric village, Turkey Creek Pueblo. Turkey Creek Pueblo is a 335 room thirteenth century ruin of which 314 rooms were excavated. Its broad and consistently reported room attribute data provide an extraordinary opportunity for understanding the social use of space in a large prehistoric community. Analysis of 31 room variables in 301 rooms reveals that patterning of room attributes is influenced by three interacting dimensions--room function, temporal change, and intrapueblo areal differentiation. Both the raw data and the results of the computer procedures are tabulated to serve as a reference for comparative analysis. Household dwellings were composed of three room types--storage rooms (small with no hearth), habitation rooms (large with rectangular hearth), and miscellaneous activity rooms (mid-sized with circular hearth). A typical dwelling had one habitation room, one or two miscellaneous activity rooms, and two or three storage rooms. Considerable variability existed in the size and organization of dwellings. Architectural analysis further suggests that households at Turkey Creek Pueblo formed the basal level of a four-level organizational hierarchy that included the suprahousehold, the dual division, and the village. The activities that occurred within the physical spaces associated with these social units are assessed, as are the mechanisms of population aggregation and village abandonment. }, keywords = {Architecture, Hopi, room typology, social organization}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=751872471\&sid=14\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Julie Lowell} } @mastersthesis {532, title = {A New Computerized X-ray Densitometric System for Tree-Ring Analysis}, volume = {MS}, year = {1984}, school = {University of Arizona}, abstract = {

A new facility for X-ray densitometric analysis is in operation at the Laboratory of Tree-Ring Research. Tree-ring specimens are cute to a uniform thickness of 1.0 mm and contact radiographs are produced. The radiographs are scanned by a modified Joyce-Loebl optical microdesitometer interfaced with an Apple II microcomputer. The film optical densities are sampled at 0.02 mm increments and stored on magnetic disks. A battery of computer programs has been developed to edit and process these data, and to transform them into annual time series of various wood density characteristics for each specimen. Several of the programs employ interactive high-resolution graphics to enable the operator to ensure that the resulting series are accurate and complete. Data produced include maximum latewood density, minimum earlywood density, total ring width, average annual density, and integrated annual density. These parameters can be employed as paleoenvironmental indicators.

}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=753909891\&sid=1\&Fmt=1\&clientId=43922\&RQT=309\&VName=PQD}, author = {McCord, Virgil Alexander Stuart} } @mastersthesis {707, title = {Inference of past atmospheric delta carbon-13 and atmospheric carbon-dioxide from carbon-13/carbon-12 measurements in tree rings}, volume = {PhD}, year = {1982}, school = {University of Arizona}, abstract = {

Carbon dioxide release from fossil-fuel burning is significant enough that we may soon experience perceptible changes in climate with important human consequences. Man\&$\#$39;s activities involving deforestation and agriculture have undoubtedly also affected atmospheric CO(,2), although quantitative, and even qualitative, net effects of these processes are incompletely understood relative to fossil-fuel production. An accurate reconstruction of past (\&$\#$39;13)C/(\&$\#$39;12)C ratios of atmospheric CO(,2) may provide key constraints on the historical activity of the biosphere as CO(,2) source or sink. Tree rings appear to be a repository of this information but there is much noise in the collection of previous reconstructions, presumably associated with site selection, radial variability, choice of representative wood chemical constituent, and subtle effects of climate on fractionation. This study attempts to avoid these pitfalls and develop a 50-yr (delta)(\&$\#$39;13)C(,ATM) record from juniper trees (genus Juniperus), in fact, by taking advantage of the influence of climate on fractionation. Trees were harvested from suitable sites in close proximity to weather stations with monthly records of temperature and precipitation. Ring material was then separated from each of the sections in 5-yr intervals from 1930 to 1979 around their full circumference, and cellulose was extracted from the wood. After measuring (delta)(\&$\#$39;13)C of the cellulose by standard mass-spectrometric techniques, a variety of (delta)(\&$\#$39;13)C vs. climate functions were examined for each interval. The most useful relationships for at most 7 of the 10 sites were (delta)(\&$\#$39;13)C with December temperature or precipitation, because the coefficients were nearly constant from one interval to the next (averaging -0.27(\&$\#$39;o)/oo(DEGREES)C(\&$\#$39;-1) for temperature and -0.04(\&$\#$39;o)/oo mm(\&$\#$39;-1) for precipitation) and the intercepts differed. Local pollution effects are believed responsible for the three anomalous sites. The separation of these regression lines of different intervals is interpreted as the response of the trees to the changing (delta)(\&$\#$39;13)C of atmospheric CO(,2) so that (delta)(\&$\#$39;13)C(,ATM) curves are constructed from this spacing. The shape of the best-fit reconstruction suggests the biosphere has acted as CO(,2) source to about 1965 and may now be a net sink. Although these conclusions are limited by certain assumptions and statistical restrictions, evidence from the recent scientific literature tends to support the increasing role of the biosphere as an important carbon sink.

}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=752855841\&sid=22\&Fmt=2\&clientId=43922\&RQT=309\&VName=PQD}, author = {Leavitt, S.} } @mastersthesis {522, title = {Comparative Analysis of Climatic Reconstructions Derived from Tree-Ring and Ice Core Indicators in Southern Greenland}, volume = {MA}, year = {1980}, school = {University of Nebraska}, keywords = {Geography}, author = {Kuivinen, Karl C.} } @book {816, title = {Tree Ring Chronologies of the Southern Hemisphere 1. Argentina}, series = {Tree Ring Chronologies of the Southern Hemisphere}, year = {1979}, publisher = {Laboratory of Tree-Ring Research}, organization = {Laboratory of Tree-Ring Research}, address = {Tucson}, keywords = {argentina, chronology, date, dendrochronology, hemisphere, south america, southern, tree ring}, author = {LaMarche, V.C. and Holmes, R.L. and Dunwiddie, P.W. and Drew, L.G.} } @book {817, title = {Tree Ring Chronologies of the Southern Hemisphere 2. Chile}, series = {Tree Ring Chronologies of the Southern Hemisphere}, year = {1979}, keywords = {chile, chronology, date, dendrochronology, south america, southern hemisphere, tree ring}, author = {LaMarche, V.C. and Holmes, R.L. and Dunwiddie, P.W. and Drew, L.G.} } @book {819, title = {Tree Ring Chronologies of the Southern Hemisphere 3. New Zealand}, series = {Tree Ring Chronologies of the Southern Hemisphere}, year = {1979}, publisher = {The Tree Ring Laboratory}, organization = {The Tree Ring Laboratory}, address = {Tucson}, keywords = {chronologies, date, dendrochronology, new zealand, southern hemisphere}, author = {LaMarche, V.C. and Holmes, R.L. and Dunwiddie, P.W. and Drew, L.G.} } @book {823, title = {Tree Ring Chronologies of the Southern Hemisphere 5. South Africa}, series = {Tree Ring Chronologies of the Southern Hemisphere}, year = {1979}, publisher = {Laboratory of Tree Ring Research}, organization = {Laboratory of Tree Ring Research}, address = {Tucson}, keywords = {africa, chronology, date, dendrochronology, south africa, southern hemisphere, tree ring}, author = {LaMarche, V.C. and Holmes, R.L. and Dunwiddie, P.W. and Drew, L.G.} } @article {768, title = {Tree-ring evidence of past climatic variability}, journal = {Nature}, volume = {276}, year = {1978}, note = {

Copies of this are available through the Tree Ring Laboratory. Please contact the lab for more information.

}, keywords = {ancient, climate, environment, paleoclimatology, past, record, tree ring}, author = {LaMarche, V.C.} } @mastersthesis {527, title = {The Effects of Fertilization on Diameter Growth in Dense Stands of Ponderosa Pine in Arizona}, volume = {MS}, year = {1976}, school = {University of Arizona}, abstract = {In 1961, fifty 1/5-acre plots were established near Blue Mountain in Arizona by Professor R.F. Wagle for the purpose of testing a selected group of fertilizers, a herbicide and a growth hormone in overcoming stagnation in Ponderosa pine stands. Thirteen treatments were applied at random on the plots. Nitrogen, phosphorus, potassium, fenuron, gibberellic acid, along with a select group of microelements were applied on the plots. Tree growth was measured at the end of each growing season by use of a dendrometer or growth band. The growth band measured circumference growth to 0.01 inches. Diameter measuements were made in 1961 and 1973 using a diameter tape. Diameter measurements were estimated to 0.01 inches. The data were analyzed using Student-Newman-Kuels{\textquoteright} test. The analyses were performed at the 95\% confidence level. The results indicated that stagnation cannot be broken using fertilizers without thinning when the stand and site characteristics of the type present in this study exist.}, author = {Leech, George R.} } @mastersthesis {525, title = {The Climate of the Great American Desert}, volume = {PhD}, year = {1972}, school = {Clark University}, keywords = {Geography}, author = {Lawson, Merlin P.} } @mastersthesis {529, title = {A Theoretical Investigation of the Evolution of a Cloud Droplet Population as Determined by Collision and Coalescence}, volume = {PhD}, year = {1972}, school = {University of Arizona}, abstract = {Droplet growth by collision and coalescence is important in the development of precipitation in convective clouds. Adequate consideration of these processes in theoretical cloud models requires knowing their effect on the spectral distribution function n(x,t)dx giving the mean number density of droplets with radii or volume in the interval x to x + dx at time t. Presently, n(x,t) is obtained by numerically solving either a stochastic transport equation for n(x,t), know as the coalescence or collection equation, or an approximation to it. Either technique is computationally time-consuming when placed in the larger context of two- or three- dimensional cloud models incorporating microphysical processes. This dissertation is a partial contribution toward a parametric description of n(x,t) designed to simplify the evaluation of n(x,t) and permit the ready incorporation of collection effects into cloud models. A parametruc description of n(x,t) is viewed here as a function of x and t containing...}, url = {http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=760225941\&sid=2\&Fmt=1\&clientId=43922\&RQT=309\&VName=PQD}, author = {Long, Alexis Boris} } @article {777, title = {Tree Rings, Glacial Advance, And Climate in The Alps}, journal = {Zeitschrift fur Gletscherkunde und Glazialgeologie}, volume = {VII}, year = {1971}, note = {

Copies of this are available through the Tree Ring Laboratory; please contact the lab for more information.

}, abstract = {

Ring-width variations in stone pine near upper treeline in the Alps show a high negative correlation with the percentage of advancing glaciers in Austria and Switzerland. The relationship is due to the similarity of climatic models for tree growth and the glacial mass budget. Tree-ring fluctuations during the period 1800-1889, prior to the compilation of glacial statistics show good agreement with historical glacial advances and periods of low summer temperatures, especially around 1820-1855. Tree-ring studies could assist in reconstructing the glacial and climatic history of the Alps, possibly for a period of 1,000 years or more.

}, keywords = {alps, austria, climatology, environment, glacial advance, glaciers, Switzerland, tree ring}, author = {LaMarche, V.C. and Fritts, H.} } @article {936, title = {Tree-Ring Growth in High-Altitude Bristlecone Pine as Related to Meteorological Factors: Research Proposal}, year = {1968}, institution = {Laboratory of Tree-Ring Research}, type = {Research Proposal}, address = {Tucson}, abstract = {

Important climatic information may be contained in long tree-ring records from the upper treeline of mid-latitude mountains. Preliminary work and the results of related research suggest that the variation in annual ring-width series from bristlecone pine (P. aristata) at the upper treeline is related to year-to-year differences in the temperature regime, in contrast to the \"drought sensitivity\" of this species near the lower forest border. Therefore, the establishment of a quantitative relationship between meterological factors and tree-ring growth at the upper treeline may permit the extension of temperature records, ad would provide an additional tool for evaluating certain environmental characteristics of remote, high-mountain regions. Direct comparison of tree-ring chronologies from \"drought-sensitive\" conifers at the lower forest border with those from \"cold-sensitive\" trees at the nearby upper treeline might also lead to the separation of precipitation and temperature effects in paleoclimatic reconstruction.

The basic approach involves the empirical comparison of tree-ring chronologies with concurrent meteorological time series in a few areas in the western United States, selected for the proximity of a bristlecone pine treeline to one or more high altitude weather stations. A number of replicated tree-ring samples will be dated, measured, standardized, and evaluated to form the basic tree-ring chronologies. testing the association between the ring-widths and meteorological factors will proceed through the development of progressively refined empirical models. Consistency with available biological data will serve as a general guide in the development of a meaningful model.

}, keywords = {bristlecone pine, cold sensitive, dendroclimatology, drought sensitive, high altitude, meteorological, NSF, pinus aristata, precipitation, temperature, tree ring}, author = {LaMarche, Valmore C.} } @mastersthesis {528, title = {A Comparative Anatomical Study on the Effects of Mutant Genes on the Pericarp and Seed Coat of Safflower (Carthamus tinctorius L.)}, volume = {MS}, year = {1966}, school = {University of Arizona}, abstract = {Achenes of safflower (Carthamus tinctorius L.) exhibiting the normal or wild type hull and the mutations for thin-hull (th), brown striped-hull (stp), gray striped-hull (gs), pigmentless (p), and light seed coat (lt) were separately and in various combinations studied anatomically to correlate the external appearance of the hull with its internal anatomy. The hull of the mature normal safflower achene was found to be composed of a pericarp, seed coat, and a one cell layer of endosperm. In studying transverse sections of the hull, the pericarp was found to be made up of two highly sclerified layers separated by a countinuous phytomelanin layer, and the seed coat was composed of a dark brown multiple outer epidermis, a layer of parenchyma cells, and an inner epidermis of crushed cells. The one cell layer of endosperm was centripetal and adnate to the seed coat. Mutations were found to differ from the normal-hull in the degree of thickness, localization of thickness, lignification, and compression of the sclerenchyma layers of the pericarp. They also differed in the absence and localization of the phytomelanin layer, the color of the outer epidermis of the integument, and the degree of thickness of the parenchymous layer of the integument.}, author = {Lockwood, Tommie E.} } @mastersthesis {524, title = {A Dendrochronological Investigation in the Clinch River Drainage, Tennessee}, volume = {MA}, year = {1938}, school = {University of Arizona}, abstract = {The purpose of this paper is to report the dendrochronological research done in northeastern Tennessee during the year 1934, 1935, and 1936. (No abstract provided)}, author = {Lassetter, Roy Jr.} } @article {702, title = {The Polar Cap of Mars}, journal = {Astronomy and Astrophysics}, year = {1894}, keywords = {astronomy, Douglass, mars, polar cap}, author = {Douglass, A.E. and Lowell, Percival} } @book {753, title = {Climate from Tree Rings}, note = {

Copies of this are available in the Tree Ring Laboratory. Please contact the curator for more information. pcreasman@ltrr.arizona.edu

}, publisher = {Cambridge University Press}, organization = {Cambridge University Press}, keywords = {climate, dendrochronology, paleoclimatology, tree rings}, author = {Hughes, M.K. and LaMarche, V.C. and Pilcher, J.R. and Kelly, P.M.} }