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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

A Spatial and Temporal Analysis of San Juan Red Ware

Bischoff, Robert Jacob 01 August 2018 (has links)
San Juan Red Ware was widely distributed throughout the Four Corners region of the U.S. Southwest between about AD 750 and 1100. Prior research indicates this ware is a marker of identity and was likely associated with feasting and other communal activities. A study of the distribution of this ware indicates that it was traded widely, but with significant variation in relative quantity between sites. This variation is likely caused by unequal access to this ware due either to a lack of access to the necessary exchange networks or by a conscious decision to not participate in the exchange of this ware. San Juan Red Ware became more widely dispersed after the first century of production, which may be indicative of increased integration between social groups. Several methods were used in this analysis, including inverse distance weighting, hexagon binning, fall-off curves, distance diagrams using Typenspektren, and social network analysis. An evaluation of these methods indicates some are more effective than others for this analysis, although the use of several complementary methods is recommended to provide a more comprehensive analysis.
272

Potential For Cattle Grazing on Sheep Range in Southwest Utah

Gutierrez-Garza, Jose Salvador 01 May 1978 (has links)
A study was conducted on pastures grazed by sheep in late winter at the Desert Experimental Range in southwest Utah. Estimates of plant cover and herbage production were obtained in 1977 and used to examine longterm trends in the vegetation. The nutritional value of the six most important species of the area was assessed by chemical analysis. In addition, a management strategy was developed for obtaining some utilization of the range during the spring and summer months without affecting the traditional winter use by sheep. Long-term records (since 1937) in cover suggest a modest increase in grasses and a decrease in shrub cover. But there are insufficient data to infer range condition and trend. Long-term herbage production data (since 1938) show a substantial increase in annual species over the last twenty years. The year-to-year variability is very high, apparently depending on the prevailing climate conditions. Grass production was less variable than shrub production. No significant difference (P<.05) in crude protein content was found between shrubs and grasses from April to September, which contrasts with the later decline in nutritive value of grasses during the winter. Phosphorus content was significantly higher in shrubs than in grasses, but the high lignin content of shrub forage made its digestibility significantly lower than for grasses. Based on the nutritional analysis of forage and long-term records of climate and plant production, a management strategy was devised to make more efficient use of the salt-desert shrub vegetation. Climatic conditions will favor good forage production about four years out of ten. Perennial grasses, annuals, and winterfat (Ceratoides lanata) showed better response to favorable climatic conditions than the other species. It is proposed in this study that, in these years of high production, the range could be used by cattle in the spring or summer, and thereby al low occasional resting of mountain summer pastures. Such opportunistic summer grazing on the desert should not be detrimental to winter sheep grazing, but the plan would need to be field-tested on an experimental or trial basis to evaluate ecological responses to increased livestock use.
273

Kvävestatus och risk för nitrifikation i två avverkade skogsområden i Halland

Beckman, Marie January 2005 (has links)
Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil. Nitrogen leaching increases after clear-cutting since the uptake by vegetation is greatly reduced. In this study the soil chemistry of two clear-cut spruce stands in Halland, in southwest Sweden, has been analyzed. A previous study in these areas has indicated higher nitrate concentrations in the groundwater in one of the areas and thus a greater nitrogen leaching. Nitrogen deposition in the two areas is estimated to be the same and therefore the soil chemistry has been analyzed to evaluate if differences in the soil can have resulted in differences in the nitrate concentration in the groundwater. The hypothesis is that the area with higher nitrate concentrations in the groundwater has properties more favorable for nitrification, which would be especially apparent in a lower carbon to nitrogen ratio. The pH and storage of nitrate, ammonium, total carbon, total nitrogen and exchangeable cations was analyzed in soil samples from both areas. In addition, a study of stand properties and previous use of the areas was made. The analyses performed in this study indicate that the soil properties could not explain the differences in nitrate concentration in the groundwater. The differences found between the areas were that the area with lower nitrate concentrations in the groundwater had higher nitrate and ammonium concentrations and higher pH in the soil. The reason for this might be that the soil in this area has larger capacity to bind elements. The fact that the soil samples were sampled during different seasons probably had a major effect on these results. The history and stand properties of the two areas were similar. According to site index one area was more fertile, which benefits nitrification. This fact was not confirmed by the analyses, but it probably caused the nitrification rate to be higher in this area. / Det stora nedfallet av föroreningar i form av kväve i framförallt sydvästra Sverige leder till försurning och övergödning av både skogsmarker och vattendrag. Kvävedepositionen i södra Sverige kan uppgå till 20 kg N/ha och år. Det kväve som inte tas upp av vegetationen ackumuleras i marken som efterhand riskerar att bli kvävemättad vilket ökar risken för kväveutlakning. Kväveutlakningen från svenska skogsmarker har visat sig kunna vara i samma storleksordning som från jordbruksmarker som anses vara en av de största orsakerna till ökande kvävehalter i sjöar och vattendrag. Kväveutlakningens storlek beror till stor del på hur stor del av markens kväveförråd som finns i den oorganiska formen nitrat eftersom den är en lättrörlig jon. Efter skogsavverkning ökar nitratutlakningen betydligt på grund av att det finns väldigt lite vegetation kvar som tar upp kväveföreningarna. I den här studien har markkemin i två avverkade granskogsområden i Halland undersökts. Tidigare studier i dessa två områden har visat att halterna av nitrat var högre i grundvattnet i det ena området än i det andra, och således var även nitratutlakningen större i detta område. Eftersom kvävedepositionen anses vara densamma i de två områdena har markemin undersökts för att finna skillnader där som kan förklara de olika nitratnivåerna i grundvattnet. Hypotesen var att det ena området skulle ha mer gynnsamma förhållanden för nitrifikation, framförallt en lägre C/N-kvot. Markens förråd av nitrat- och ammoniumkväve, totalkol, totalkväve, utbytbara katjoner samt pH undersöktes i båda områdena. En studie av områdenas historia gjordes även för att kunna utesluta skillnader där som kunde ge upphov till skillnaden i nitrat i grundvattnet. Slutsatsen som kan dras från studien är att de analyserade egenskaperna inte visade på mer gynnsamma förhållanden för nitrifikation i det ena området än i det andra. Ingen skillnad i C/N-kvot uppmättes. Skillnaderna som hittades var att området med lägst halter av nitrat i grundvattnet hade högst halter av oorganiskt kväve i marken och högre pH. Att nitrathalterna var högre i grundvattnet men inte i marken kan ha sin förklaring i att marken i det ena området har större förmåga att binda till sig kväve vilket gör att det inte lika lätt kommer ut i grundvattnet. Antagligen spelade det stor roll för dessa resultat att jordproven tagits vid olika årstider. Undersökningen av tidigare användningsområde i skogarna visade att de hade en tämligen liknade historia. Det ena området har enligt ståndortsindex högre bördighet vilket gynnar nitrifikation. Detta framgick dock inte av analyserna men är antagligen orsaken till de högre nitrathalterna i grundvattnet i detta område.
274

A Study of the Development of the Greater Southwest Region in China

Liu, You-ting 15 July 2010 (has links)
none
275

Characterization of Miocene-Pliocene carbonate platforms, southern Southwest Palawan Basin, Philippines

Sta. Ana, Ma. Corazon Victor 02 June 2009 (has links)
Isolated carbonate platforms and buildups of the Likas Formation provide a long record of carbonate sedimentation in the southern end of the Southwest Palawan Basin. While most carbonate platforms terminated in early Miocene and middle Miocene time in northern parts of western offshore Palawan (i.e. Northwest Palawan Basin and central South Palawan), carbonate deposition began later in the south during late middle Miocene time. Carbonate platforms of the Likas Formation developed in the Paragua sub-basin, which is interpreted to be a depozone eastward of the Palawan accretionary wedge in the structurally complex Southwest Palawan Basin. A regional 2D seismic grid and borehole data from four wells were used to analyze the growth patterns of the carbonate platforms, identify seismic facies, and reconstruct the evolution of the platforms. The carbonate platforms developed on the folded and faulted middle to premiddle Miocene siliciclastic strata. These older siliciclastic units were thrusted onto the southern end of the North Palawan microcontinental fragment, which represents a block of continental crust that drifted southward from South China during early Tertiary time. The platforms aggraded over time and backstepped to keep pace with increasing rates of relative sea level rise. Karst features are recognizable on seismic sections and indicate that the platforms were subaerially exposed at various times during their development. The platforms exhibit variable morphology from faulting and tilting. The platforms terminated in early Pliocene time, as relative sea level continued to rise, and were buried by deep-marine siliciclastic units.
276

Mesh regulations of bottom trawl for the protection of economic immature fishes off southwestern Taiwan

Huang, Meng-Hsun 09 September 2008 (has links)
The present research adopts with the application of the sequential mesh regulations on bottom trawl to study how to protect economic immature fishes. The experimental design includes first the determination of the relationships of fish size and the price per weight (PPW) of the economic demersal fishes sold as the one-hundred Dollars-a-plate manner in Tunkang and Zihguan fish markets in the southwestern coast of Taiwan. The obtained results were used to yield the catch of smaller size fishes and the lower PPW for regulating the economic immature fishes. The three kinds of regulated fish size were defined as the smallest surveyed size, smallest economic size, and smallest matured size. These regulated fish size were used as the body lengths of 50% selection (L50) to calculate the regulating mesh size. This study presents that four steps are needed for the sequential mesh regulations of bottom trawl in the southwestern Taiwan. The first step is to regulate the mesh size between 35 and 45 mm for banning bottom trawler to catch fishes smaller than the smallest surveyed fish size. The objective of first step is to reduce the bycatch without affecting the landings of economic immature fishes sold in the fish market. The second step is to regulate the mesh size between 50 and 60 mm for banning bottom trawler catch fishes smaller than the smallest economic fish size, and to reduce the catch of smaller size fishes and the lower PPW of economic immature fishes. The third step is to regulate the mesh size between 65 and 70 mm for banning bottom trawler to catch fishes smaller than the smallest matured fish size. This is also to reduce the catch of economic immature fishes, and to increase the recruitment. The fourth step is to regulate the mesh size between 70 and 82 mm for banning bottom trawler catching the lower PPW of economic fishes that is not large enough to reach their optimal PPW. The present research provides important data results for regulating the mesh size of bottom trawler operation for the achievement of sustainable coastal fishery in Taiwan.
277

Development of luminescence dating using feldspar and its application to river terraces in north piedmont of Chinese Tianshan

Fu, Xiao, 付晓 January 2014 (has links)
abstract / Earth Sciences / Doctoral / Doctor of Philosophy
278

Improved Types of Sheep for The Southwest; With a Chapter on the Sheep and Tunis and Algeria

Wilson, F. W., Vinson, A. E. 30 November 1912 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
279

Architectural Communities of Practice: Ancestral Pueblo Kiva Production During the Chaco and Post-Chaco Periods in the Northern Southwest

Ryan, Susan Christine January 2013 (has links)
This study analyzes the vernacular architecture of ancestral Pueblo kivas dating from the Pueblo II (A.D. 900-1150) and Pueblo III (A.D. 1150-1300) periods in the northern, middle, and southern San Juan regions in the American Southwest in order to shed light on communities of practice and their social, temporal, and spatial production practices. This research specifically examines kivas--or round rooms used for ritual and domestic activities--to address how architecture, as a symbolic system, emphasized the ways in which sign-objects were actively mediated by communities of practice and how their semiotic signatures can shed light on material expressions of ancestral Pueblo group identity. The theoretical perspectives used within this study are influenced by the work of educators and anthropologists analyzing the processes by which knowledge and skills are learned and transmitted from one generation to the next--these processes are responsible for the continuity of all material culture. This study adopts a community of practice approach to analyzing ancestral Pueblo kiva architecture for two primary reasons. First, the continuity of all material culture--including architecture--depends on the processes by which knowledge and skills are learned and transmitted from one generation to the next. Second, architectural production is an additive technology in which variations in learning frameworks are encoded as choices made by production groups during construction. The methodological applications used within this study are crucial to the identification and analysis of communities of practice in that additive vernacular architectural forms are encoded with learned production techniques. Learned production techniques were materially manifested as unique modes of fabrication and were recognized as the semiotic signatures of particular communities of practice. This study is the seedling from which larger research may germinate, providing insights into large-scale anthropological processes including identity formation and maintenance, population movement, the psychological effects of population aggregation, the nature and extent of social networks, the transmission and practice of learning, the production and movement of material culture, and the development and dissolution of political and ritual organization.
280

Incised decoration in the prehistoric pottery of the Southwest

McWhirt, Martha Jean, 1910- January 1935 (has links)
No description available.

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