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A Palynological Study of Landscape Change During the Spanish Colonial Period in the U.S. SouthwestArendt, Nicole Marie January 2010 (has links)
The introduction, intentional or otherwise, of plants (both cultivated plants and weeds), animals, and technologies that occurred with Spanish colonization in the Southwest had profound impacts on vegetation and landscape that are reflected in larger changes in indigenous land and resource use, culture, and identity. Archaeological palynology provides information on both the environmental and agricultural impacts of colonialism. Through the study of two sites occupied during the colonial period, in different areas, reflecting different experiences of colonized groups, the range of effects of introductions is investigated. Paa-ko, in New Mexico, was occupied in the early colonial period and was more peripheral to the colonial system than was the second site, Tumacacori, in southern Arizona, the location of a mission that was occupied into the mid-1800s.The identification of introductions, including both new plants and new ways of cultivating and processing plants, in the pollen record is central to this study. The differentiation, using pollen diameters, of grasses is particularly important, although studies of reference pollen show a great overlap between these types. Because of the importance of pollen diameters for the identification of this and other pollen types, factors that could affect pollen size, including processing methods, which did not seem to have much effect, and mounting media (and time since processing), which had rather dramatic effects on diameters, are also important. These and other experimental studies conducted to provide analogs to agricultural and processing areas that would have been seen in the Spanish colonial period, can assist in the interpretation of pollen samples from sites of this period, including the two sites discussed here. While the pollen evidence from Paa-ko demonstrates a continuation of the cultivation of native crops, including maize and squash, and the absence of cultivation of introductions, pollen from Tumacacori demonstrates the absence of cultivation of native crops, particularly maize, and, possibly, cultivation of wheat, in the area closest to the mission and most heavily influenced by missionary control, reflecting, perhaps, the greater integration of Tumacacori into the colonial system and a greater acceptance and use of introduced crops in this later colonial period.
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Human-environment interactions during the Mid-Holocene in CumbriaGrosvenor, Mark James January 2014 (has links)
The influence of anthropogenic activity on the natural environment is constantly changing. A series of major developments in human culture have resulted in a shifting nature of impact. Separating change attributable to humans and the change resulting from natural forcing is complex. This study investigates the degree of human impact during the onset of agriculture when humans were shifting from a hunter-gatherer lifestyle to herding livestock and the cultivation of plants. This cultural development is known as the Mesolithic-Neolithic Transition within Europe. In particular, this project focuses on the nature of environmental change in Cumbria in the British Isles during the mid-Holocene. This region exhibits strong contrasts in landscape from coastal lowlands to mountainous uplands. Cumbria also has a rich record of archaeological sites and environmental reconstructions, but existing datasets have not allowed for detailed comparisons of the different landscapes. Two contrasting sites (one upland, one lowland) were investigated to produce a high-resolution environmental reconstruction including: vegetation change, burning patterns, catchment erosion and climatic changes. A radiocarbon chronology was produced for each site investigated. This was used to re-address the archaeological record and in particular, determine the details of the impact of humans on the landscape. Key differences are highlighted in the nature of human impact during the late-Mesolithic and early-Neolithic in contrasting landscapes with different types of land-use. There is an estimated temporal offset of around 200 years between similar events occurring in lowland and upland landscapes. Climatic variability indicates only small fluctuations and is unlikely to account for the extent of vegetation modification on its own. It is clear Neolithic activity is far more intensive than Mesolithic activity, but importantly the scale of impact in the upland landscape is far more extensive than the archaeological evidence would suggest. Furthermore, the upland landscape appears to recover relatively quickly after clearance events, whilst in the lowland environment, the open vegetation landscape remains far more dominant.
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A palynological investigation of the offshore Cretaceous sequence on the south-west coast of South AfricaSandersen, Andrea 19 September 2008 (has links)
Until recently, there has been very limited academic palynological study of South Africa’s
offshore west coast Cretaceous sequences. For this thesis, an in-depth study of the palynological
sequence as well as a combination of other disciplines was undertaken for Offshore Sites C-B1
and O-A1, situated off the west coast of Cape Town. The study has yielded copius amounts of
mostly well-preserved palynomorphs (trilete spores, pollen, diniflagellate cysts and foraminiferal
test linings) ranging from Early to Late Cretaceous in age.
Both Offshore Sites consist mostly of sandstone and siltstone lithologies but it was the
carbonaceous mudstone-rich intervals that were targeted for palynomorph extraction. The
Petroleum Agency, SA (previously SOEKOR) has identified ten time periods (nine in the
Cretaceous and one in the Tertiary) from these lithologies but for this study, only eight of these
time periods that span the Barremian to the Campanian stages of the Cretaceous were utilized..
Over 550 samples that include cuttings, sidewall and core samples, have been provided by the
Petroleum Agency, SA representing offshore Cretaceous sedimentary strata from the west coast
of South Africa. All of these samples have been analysed palynologically. A wide variety of
palynomorphs have been described from these samples and are fully illustrated. These include
angiosperms, gymnosperms, spores of known and unknown botanical affinity, four species of
algae and one species of fungi. These palynomorphs are compared with published descriptions
and illustrations to aid and effect identifications. Several new palynomorphs were found,
however formal naming will only be undertaken at a later stage.
Palynological data indicates that the gymnosperms and ferns dominated the plant groups during
both the Early and Late Cretaceous intervals of both Offshore Sites. Angiosperms only really
became a significant part of the vegetation during the Late Cretaceous. Gymnosperms found at
both Offshore Sites are dominated by the genera Classopollis, Podocarpidites, Zonalapollenites,
Balmeiopsis and Exesipollenites. Cyathedites, Gleicheniidites and other trilete schizeaceous
types dominated the spore population. The information gained from the identification of the
microfossils present in these two Offshore Sites contributes not only to amplifying the
biostratigraphy of this part of the geologic column but also to reconstruct the Cretaceous
palaeoflora and palaeo-environment.
The age ranges of the palynomorphs present have provided a general Cretaceous age bracket for
these two Offshore Sites, supporting the Petroleum SA’s findings. However these palynomorphs
do not always age-define the level they were found in and on more than one occasion Tertiary
palynomorphs were located at the base of the Cenomanian and Turonian stages (Late Cretaceous
Period).
The pollen and spore assemblage include many species that are known from both northern and
southern hemispheres, although the northern hemisphere representatives are usually represented
by only a few individuals. There is a noticeable difference between the Early and Late
Cretaceous floras. Early Cretaceous floras are dominated by gymnosperms and fern spores with
only a few angiosperm pollen grains present. Late Cretaceous flora is much richer in
angiosperm pollen and in Tertiary flora. Botanical affinities were used to reconstruct the
palaeoflora of both Offshore Sites. The forests that existed during the Cretaceous were probably
cool, moist and temperate, located in the highlands of a slowly developing rift valley. The
dominant trees in these forests produced palynomorphs attributable to Podocarpaceae,
Microcachryidites, Balmeiopsis and Exesipollenites. The lowland woodlands consisted primarily
of cheirolepideacean conifers with the undergrowth including varieties of ferns and bryophytes.
Results of the pollen and spore analysis suggest that neither west coast sites fits into any
established pollen zonation. Therefore new pollen zones were established for this thesis and will
hopefully contribute to the understanding of the palaeoflora of this part of the southern
hemisphere. Zones are used to designate each Offshore Site into divisions that characterize the
essential changes in the vegetational history as well as divide the history of the palaeoflora in the
Cape Basin. Offshore Site C-B1 consists of 5 zones (CI, CII, CIII, CIV and CV) and four
subzones namely Subzone CI-A, CI-B, CV–A & CV–B. Offshore Site O-A1 is comprised of 5
zones namely OI, OII, OIII, OIV and OV.
Palaeoenvironmental reconstructions were deduced by studying the palaeoflora and palynodebris
in each zone / facies of each Offshore Site. The Early Cretaceous was tropical, humid and warm
with palaeoflora indicators such as Classopollis and Ephedripites suggesting the start of a shift
towards warmer more semi-arid conditions. In comparison, the beginning of the Late Cretaceous
assemblages suggested a shift to hotter, humid and then semi arid conditions. By the end of the
Late Cretaceous the environment had once again reverted back to warm, wet and humid
conditions.
Using the core depth as scale, the relative frequencies of the organic matter types in Offshore
Sites C-B1 and O-A1 were plotted using CONISS – the distance cluster analysis program which
identified four main groups of samples in each core (Facies CB- D1 to D4 and OA – D1 to D4)
on the basis of their organic content. These eight palynofacies assemblages (Facies CB- D1 to
D4 and OA – D1 to D4) show the gradual and immediate changes in palynodebris and could
reflect environmental and geological changes. The palynodebris component for both Offshore
Sites supports the origin of the sediments deposited into the Cape Basin as continent-derived and
transported into the Cape Basin via fresh water sources. The presence of sporomorphs and resins
in the palynodebris reflects a great diversity of hinterland vegetation. Plant and cuticle
palynodebris found at both Offshore Sites suggest stable dry conditions terrestrially and near
shore deposition. Amorphous organic material and the presence of green algae throughout both
Offshore Sites indicate a terrigenous source associated with shallow fresh to brackish water of
lagoons and swamps. The presence of marine palynomorphs supports deposition in a marine or
saline esturine marsh environment.
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The palynology of tertiary sediments from a palaeochannel in NamaqualandDe Villiers, Susan E. 02 September 2013 (has links)
Thesis (Ph.D.)--University of the Witwatersrand, Faculty of Science, 1997.
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A formação Irati (Grupo Passa Dois, Permiano, Bacia do Paraná) no furo de sondagem FP-01-PR (Sapopema, PR) /Lages, Leandra Costa. January 2004 (has links)
Resumo: A Formação Irati (Grupo Passa Dois, Permiano, Bacia do Paraná), subdividida nos membros Taquaral e Assistência, foi estudada no furo FP-01-PR da CPRM em Sapopema, PR (UTM 7.384.500N/562.000E), onde apresenta 44,5 m de espessura. Visando discutir os paleoambientes e a idade da formação, o trabalho envolveu descrições dos testemunhos, petrografia dos carbonatos, geoquímica dos pelitos (%COT e %S), palinologia e correlações estratigráficas. Os principais resultados inéditos são: 1) O Membro Taquaral, embora predominantemente síltico, apresenta finas coquinas de bivalves e porções areno-margosas no final de um ciclo granocrescente ascendente. 2) Tanto na base, quanto no topo da formação, há prováveis lags transgressivos constituídos por delgados bone beds de peixes. 3) Correlações entre furos da borda leste da bacia revelaram modificações na taxa de subsidência na região do Arco de Ponta Grossa, de relativamente alta para baixa, respectivamente para os membros Taquaral e Assistência. Tal fato e as marcantes diferenças litofaciológicas sugerem a separação dos membros por discordância. 4) As assembléias palinológicas, embora mal preservadas e constituídas quase apenas por grãos de pólen, algas Bothryococcus (dulçaqüícolas) e acritarcas (marinhos), indicam idade artinskiana por correlações com a África. 5) Análises críticas e algumas interpretações alternativas são apresentadas em relação aos paleoambientes e às seqüências estratigráficas. / Abstract: The Irati Formation (Permian Passa Dois Group, Paraná Basin) divided into the Taquaral and Assistência members, is 44,5 m thick in CPRM's FP-01-PR borehole at Sapopema Municipality, Paraná State (UTM 7.384.500N/562.000E). Aiming paleoenviromental and age discussions, the work envolves description of cores, carbonate petrography, geochemistry of pelites (%TOC and %S), palynology and stratigraphic correlations. The main inedit results are: 1) The predominantely siltic Taquaral Member has thin bivalve coquinas and sandy marl portions at the end of a coarsening upwards cycle. 2) Both at the base and the top of the formation, there are probable transgressive lags constituted of thin fish bone-beds. 3) Correlations between boreholes at the eastern border of the basin reveal modifications in the subsidence rate in the region of the Ponta Grossa Arch, from relatively high to low, respectively for the Taquaral and Assistência members. This fact and the strong lithofaciological differences suggest a discordant boundary between the members. 4) The palynological assemblages, although badly preserved and almost exclusively constituted of pollen grains, Bothyococcus algae (freshwater) and acritharcs (marine), through correlations with Africa, indicate an Artinskian age. 5) Critical analysis and some alternative interpretations are presented for the paleoenvironments and stratigraphic sequences. / Orientador: Rosemarie Rohn Davies / Coorientador: Paulo Alves de Souza / Banca: Silvia Helena de Mello e Sousa / Banca: Mariselma Ferreira Zaine / Mestre
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The roles vacuolar sorting receptor (VSR) and secretory carrier membrane protein (SCAMP) in pollen germination. / CUHK electronic theses & dissertations collectionJanuary 2010 (has links)
Wang, Hao. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 83-93). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Palynology of a coal seam in Karoo deposits of Botswana and correlation with southern African coal-bearing strataBarbolini, Natasha 02 December 2010 (has links)
A significant amount of palynological work has been done on southern African coal
seams in the Ecca Group, but as yet there is little consensus on how these areas relate to
each other. This study investigated the palynology of a coal seam from Mmamantswe
(Mmamabula area), Botswana, approximately 70 km north-east of Gaborone. A total of
124 samples were taken from two borehole cores and subjected to acid preparation,
oxidation and acetolysis. Coal samples were found to be barren of palynomorphs. Fifty
carbonaceous mudstones and siltstone samples yielded twenty-two productive samples.
A thermal alteration index of 3.0-3.5 was assigned for the sediments. Palynomorph
diversity was high, with 64 genera and 90 species present, dominated by trilete and alete
spores. This indicates a parent flora of mostly lower order lycopods, sphenophytes and
ferns. Non-taeniate bisaccate and monosaccate pollens were scarce, and striates
extremely rare (only two species), suggesting an autochthonous origin for the coal
swamp. The Mmamantswe core was sub-divided into five microfloral assemblage
zones. A transition from monosaccate dominance in the lower part of the core, to equal
numbers of monosaccates and non-taeniate bisaccates in the upper part of the core, was
seen. As the Mmamantswe palynoflora possesses elements of both the Late
Carboniferous glacial floras and the mid-Permian coal floras, it is thought to represent a
cross-over assemblage dating to soon after the Permo-Carboniferous boundary
(Sakmarian and Early Artinskian). The Mmamantswe assemblage can be correlated
with Assemblage Zones II and III of Falcon (1975a); Biozones B and C of MacRae
(1988); and Zones 1, 2 and 3 of Anderson (1977) but does not fit well into any existing
biozonation. The Mmamantswe palynoflora was most similar to that of Milorgfjella,
Dronning Maud Land, Antarctica (Larrson et al. 1990) and the No. 2 Seam, Witbank,
South Africa (Falcon 1989). Taphonomic controls on palynomorph preservation suggest
that future studies should also attempt to focus on Permian sediments not containing
coal, as microfloral assemblages from coal seams tend to be autochthonous, and subject
to local climatic influences. Accordingly they are not as useful for inter-basinal
correlation across Gondwana.
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A high resolution re-examination of vegetation and climate change in the Jarbidge Mountains of northeastern Nevada from 4, 000 to 2000 cal yr BPNorman, Kelly. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / "May, 2007." Includes bibliographical references (leaves 66-68). Online version available on the World Wide Web.
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Pollen from Laguna Verde, Blue Creek, Belize: Implications for Paleoecology, Paleoethnobotany, Agriculture, and Human SettlementMorse, Mckenzie 2009 August 1900 (has links)
This dissertation is a palynological examination of the Mayan archaeological site at Blue Creek, northwestern Belize. This study uncovers more than 4,500 years of environmental and agricultural history of the region, which can be related to human incursion, habitation and plant use, abandonment, and reoccupation of the region.
After an historical and ecological overview of the study site, there follows an explanation of procedures for collecting, sampling, processing, identifying, and counting the fossil pollen from the area. Evidence from archaeology, paleoecology, and physical anthropology is used to construct a model for the first entry of humans into the Maya area. Examinations are made of Archaic Period paleoecology and the cultural developments that set the stage for the advancement of Maya culture.
Next, the physical environment of Blue Creek is explored, and its stability is assessed. This information leads to an assessment of the possibility of drought or soil degradation during the height of Mayan civilization, and contributes to the current understanding of the Maya Collapse at Blue Creek.
Mayan agricultural methodologies are explained, and the changes to traditional production systems that resulted from European colonization are described. A model of agricultural development is proposed.
The plant taxa identified in the Laguna Verde pollen core are listed and described. Finally, the Laguna Verde pollen core is interpreted in terms of the vegetation associations and environmental conditions represented by each stratum. This dissertation is a palynological examination of the Mayan archaeological site at Blue Creek, northwestern Belize. This study uncovers more than 4,500 years of environmental and agricultural history of the region, which can be related to human incursion, habitation and plant use, abandonment, and reoccupation of the region.
After an historical and ecological overview of the study site, there follows an explanation of procedures for collecting, sampling, processing, identifying, and counting the fossil pollen from the area. Evidence from archaeology, paleoecology, and physical anthropology is used to construct a model for the first entry of humans into the Maya area. Examinations are made of Archaic Period paleoecology and the cultural developments that set the stage for the advancement of Maya culture.
Next, the physical environment of Blue Creek is explored, and its stability is assessed. This information leads to an assessment of the possibility of drought or soil degradation during the height of Mayan civilization, and contributes to the current understanding of the Maya Collapse at Blue Creek.
Mayan agricultural methodologies are explained, and the changes to traditional production systems that resulted from European colonization are described. A model of agricultural development is proposed.
The plant taxa identified in the Laguna Verde pollen core are listed and described. Finally, the Laguna Verde pollen core is interpreted in terms of the vegetation associations and environmental conditions represented by each stratum.
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Pollen analysis of the Tule Springs site, NevadaMehringer, Peter J. January 1968 (has links)
No description available.
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