Tracking seed dispersal using traditional, direct measurement approaches is difficult and generally underestimates dispersal distances. Variation in chloroplast haplotypes (cpDNA) offers a way to trace past seed dispersal and to make inferences about factors contributing to present patterns of dispersal. Although cpDNA generally has low levels of intraspecific variation, this can be overcome by assaying the whole chloroplast genome. Whole-genome sequencing is more expensive, but resources can be conserved by pooling samples. Unfortunately, haplotype associations among SNPs are lost in pooled samples and treating SNP frequencies as independent estimates of variation provides biased estimates of genetic distance. I have developed an application, CallHap, that uses a least-squares algorithm to evaluate the fit between observed and predicted SNP frequencies from pooled samples based on network topology, thus enabling pooling for chloroplast sequencing for large-scale studies of chloroplast genomic variation. This method was tested using artificially-constructed test networks and pools, and pooled samples of Lasthenia californica (California goldfields) from Whetstone Prairie, in Southern Oregon, USA. In test networks, CallHap reliably recovered network topologies and haplotype frequencies. Overall, the CallHap pipeline allows for the efficient use of resources for estimation of genetic distance for studies using non-recombining, whole-genome haplotypes, such as intra-specific variation in chloroplast, mitochondrial, bacterial, or viral DNA.

In urban riparian areas, vegetation composition may be affected by urban land use changes at both the stream reach and the watershed scale. Moreover, the mechanisms by which seeds disperse may be affected both by reduction in seed sources due to vegetation removal and by the urban stream syndrome that produces flashier hydrographs and incised channels. I hypothesized that vegetation communities with high cover of native and hydrophilic species would be found in watersheds with high forest cover, while more limited cover of these species would be found in highly developed watersheds. Additionally, to examine the dispersal mechanisms contributing to these patterns, I hypothesized that 1) more seeds would be deposited in riparian areas by water than by wind; 2) the number of seeds deposited by streams would decrease as watershed urbanization increased; and 3) seeds deposited in the most urbanized sites would be primarily from species with traits favoring deposition by water, including large seed size and presence of a dispersal appendage. To investigate relationships between urban land cover types and riparian vegetation, I surveyed 30 randomly-selected riparian forests in the Portland-Vancouver metro area and related vegetation assemblages to watershed land cover. Vegetation was mapped to the nearest 1cm along three transects in each site. Land cover was characterized both within a 500m buffer around each site, and within the entire watershed. Relationships between land cover and vegetation assemblages were investigated using nonmetric multidimensional scaling and classification trees. To investigate the effect of watershed urbanization intensity on riparian seed deposition, I collected seeds deposited in nine riparian sites along a gradient of watershed total impervious area (TIA). I used a stratified-random approach to select sites. In each site, wind-deposited seeds were collected in funnel traps three times, and water-deposited seeds were collected in turf traps four times, over a 15-month period, spanning both wet and dry seasons. Consistent with my first hypothesis, communities dominated by native understory species were found exclusively in watersheds that were at least 15% forested by evergreen canopy. These findings suggest that native understory communities can persist in urban areas if adequate surrounding forest cover is maintained. Regarding my second major hypothesis, significantly more seeds were deposited by water than by wind (p < 0.05; mean of 155 seeds per turf trap; mean of 30 seeds per funnel trap). For shrubs, for species primarily dispersed by animals, and for species under 15m tall, hydrochory significantly increased delivery to riparian areas over the background seed delivery rate measured in funnel traps. There was a significant reduction in the number of seeds deposited by streams as TIA increased (adjusted R² = 0.74; p < 0.01). Deposition of shade-tolerant seeds decreased significantly, while deposition of non-native seeds increased significantly (p < 0.05) with watershed TIA and with development within 500m from the site, likely due to alterations of seed source pools of these species. Findings indicate that in an urban setting, small streams have the capacity to act as dispersal vectors, connecting fragmented populations that may otherwise be seedlimited. Riparian forests with diverse understory assemblages maintained by ongoing seed deposition may persist in urban areas with sufficient watershed forest, as well as with low development cover, in both the whole watershed and the near-stream area. Total seed deposition by streams, as well as deposition of shade-tolerant species, can be expected to decrease with increased watershed development. Results suggest that passive approaches to restoration of riparian forest understories in urban watersheds will only likely be successful with sufficiently high forest cover and with restricted development.

Woody plant encroachment is a phenomenon whereby trees and shrubs invade grasslands or increase in an already wooded area, resulting in lower yields of herbaceous plants and a reduction in the carrying capacity of rangelands. It is not only the extent of woody plant encroachment, but also the rate at which it occurs, that is a major concern for livestock ranchers interested in herbaceous production. The question of what causes woody plant encroachment still remains unanswered. Animals consume a considerable amount of woody plant seeds during the dry season and could be responsible for spreading undesirable species to new areas or they could enhance the dispersal of species already established. However, under natural conditions, seed dispersal does not guarantee seed germination, which depends on appropriate environmental and seed survival conditions. To better understand the mechanisms involved in woody plant encroachment, we studied the effects of livestock (goats, sheep and cattle), diet quality (high-quality (Medicago sativa hay) vs. low-quality (Digtaria eriantha hay)), seed characteristics (size, shape and hardness), grass competition and fire on germination and seedling recruitment of Dichrostachys cinerea and Acacia nilotica seeds. These objectives were achieved by conducting the following trials: a) recovery and germination of D. cinerea seeds fed to goats, b) diet quality on germination of Dichrostachys cinerea and Acacia nilotica seeds fed to ruminants, c) the effects of gut passage and dung fertilization on seedling establishment of Dichrostachys cinerea and Acacia nilotica seeds and d) the effects of gut passage, dung fertilization, trampling, grass competition and fire on seedling recruitment of the two woody plant species. During the first trial, seed recovery rate of D. cinerea seeds consumed by goats, either voluntarily after mixing them with feed pellets (mixed), or by force-feeding (gavaged) and germination percentage were measured. Seed recovery for the gavaged treatment (32.7%) was significantly higher than for the mixed treatments (9.9%; P < 0.001). Seeds that passed through the digestive tract (mixed (35.5%)) and gavaged (31.2%) treatments) had a significantly higher germination percentage than untreated seeds (19.0%). A non-negligible proportion of D. cinerea seeds remained intact after chewing and passage through the digestive system, and their germination percentage increased. In the second trial, I tested the effects of animal species (goats and sheep, goats and cattle), diet quality (Medicago sativa hay and Digitaria eriantha hay), and seed characteristics (size, shape and hardness) on the effectiveness of animal seed recovery and germination of D. cinerea and A. nilotica seeds. The trial was divided into two experiments. In the first experiment, a significant interaction effect of animal species (goats, sheep), diet (high-quality hay, low-quality hay) and seed species (A. nilotica seeds, D. cinerea seeds) was found on percentage germination (P < 0.0001). There was also a higher percentage seed recovery (P < 0.009) when animals were offered high-quality hay (47.4% + 4.65) compared to low-quality hay (30.2% + 3.24). In goats fed D. eriantha hay, A. nilotica seed germination (9.38% + 3.66) was higher (P < 0.05) than goats fed D. eriantha hay and D. cinerea seeds (6.78% + 1.13). A greater germination percentage was observed in goats fed M. sativa hay with D. cinerea seeds (6.71% + 1.53) than goats fed M. sativa hay with A. nilotica seeds (2.50% + 0.97) (P < 0.05). In the second experiment, animal species had a positive impact, both on seed recovery (P < 0.0325; goats 32.0% + 6.44; cattle 50.3% + 4.27) and germination percentage (P < 0.055; goats 14.1% + 1.48; cattle 9.3% + 0.94; control: D. cinerea 0.64 + 0.06; A. nilotica 0.59 + 0.07). Animal species in experiment one (goats and sheep) and two (goats and cattle) was most important for seed recovery and germination. However, diet (M. sativa hay and D. eriantha hay) and seed species (D. cinerea, A. nilotica seeds) also had important effects on germination of seeds retrieved from experiment one. The interaction of animal species and size, diet quality, and seed characteristics (size, hardness) all played a major role in recovery of viable and scarified seeds either alone or in combination. I also studied the effects of seedling emergence, seedling establishment and recruitment of dispersed A. nilotica and D. cinerea seeds by goats and cattle under natural conditions. The interaction effect of animal species, seed recovery day and seed germination treatment/planting method was significant on seedling recruitment. Seeds retrieved from goats in the last four days and planted 2 cm in the soil with dung (25.85% ± 0.46) and seeds planted 2 cm in the soil with no dung (24.77% ± 0.35), recruited significantly better than seeds planted on top of the soil (16.98% ± 0.46). The results also indicated significant differences in percentage seedling recruitment among goats, cattle and control, with goats and cattle having the highest percentage recruitment than controls or untreated seeds. Overall, seeds can potentially germinate and recruit following passage through the gut, thereby facilitating woody plant encroachment. The results of the last trial showed that seed passage through the digestive tract of goats and cattle compared to untreated seeds (i.e. not ingested) played an important role in improving germination through seed scarification. However, seed recovery by livestock does not guarantee seedling establishment survival, survival and recruitment. Fire and grass mowing treatments affected seedling emergence, seedling survival and recruitment, most probably because of reduced grass competition, thereby reducing competition for resources (light, water and nutrients) between grasses and seedlings. In conclusion, this study indicated that animal species (goats, sheep and cattle), associated diet (low-quality vs. high-quality), seed species (D. cinerea and A. nilotica) and seed characteristics (size, shape, hardness) all played an important role in seed germination. The interactions of animal species, fire, dung, and season either directly or indirectly were pivotal in the emergence, survival and recruitment of D. cinerea and A. nilotica seedlings. Thus, acid scarification in the gut of herbivores in combination with their indirect effects (dung fertilization) and removal of grass competition (either by fire or mowing) can facilitate seedling emergence, seedling survival and recruitment of woody plant species, which may lead to woody plant encroachment. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.

Bibliography: p. 191-200. / 200 p. : ill. (chiefly col.), map (fold.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Persistence mechanisms of Erodiophyllum elderi are investigated in terms of life history strategies and patchy population theory. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1999

Bibliography: p. 191-200. Persistence mechanisms of Erodiophyllum elderi are investigated in terms of life history strategies and patchy population theory.

Made available in DSpace on 2014-06-11T19:23:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-05-29Bitstream added on 2014-06-13T19:08:48Z : No. of bitstreams: 1 rother_dc_me_rcla.pdf: 880592 bytes, checksum: 63ebac83ba6dcb09cddf42b5445e1892 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho teve como objetivos verificar como variam a chuva de sementes e o estabelecimento de plântulas entre ambientes colonizados (B) e não colonizados (SB) pelo bambu Guadua tagoara na floresta Atlântica do Parque Estadual Carlos Botelho, Sete Barras - SP. Foram utilizados 40 coletores e 40 parcelas de 1m2 em cada ambiente com monitoramento mensal no período de um ano. SB apresentou 38,71% mais sementes que B, maior riqueza, menor diversidade e equidade. Os ambientes mostraram uma alta similaridade no número de espécies de sementes em comum e com abundâncias semelhantes. SB apresentou maior média de sementes/mês e maior média de sementes/espécie. A densidade absoluta de sementes por coletor não variou entre ambientes, entretanto variou entre meses. Em relação às plântulas, B apresentou maior abundância, maior densidade, maior riqueza, maior dominância de Euterpe edulis, entretanto menor diversidade e equidade que SB. Os dois ambientes se apresentaram com baixa similaridade na composição e na abundância de plântulas por espécie. Em B houve maior média de plântulas/mês enquanto a média de plântulas/espécie foi semelhante entre ambientes. A densidade absoluta de plântulas de E. edulis variou entre meses e ambientes, com maior número em B. Para as demais espécies a diferença se deu entre ambientes e meses, porém maior número em SB. Quando analisadas todas as plântulas em conjunto houve diferença entre meses e ambientes. Maior média de plântulas emergiram e morreram no ambiente com bambu a cada mês. A taxa de sobrevivência variou segundo o tipo de ambiente e ao longo do ano. Nos dois ambientes E. edulis foi a única espécie que não apresentou qualquer tipo de limitação demográfica... / This project aim to evaluate how the seed rain and the seedling establishment varied between environments with (B) and without (WB) the bamboo Guadua tagoara in the Atlantic forest of Carlos Botelho State Park, Sete Barras - SP. Forty traps and forty plots of 1m2 were placed within each patch type during one year of monthly monitoring. We recorded higher richness and more seeds in WB than in B, nonetheless, diversity and equitability were lower. Both environments showed high similarity in composition and abundance of seeds per specie. The average of seeds per month and seeds per specie was higher in WB. Also, the absolute density of seeds per trap varied predictable in time but there was not difference between B and WB. In respect to seedlings, B environment showed higher abundance, density, richness and dominance of Euterpe edulis, although diversity and equitability were lower than in WB. We found low similarity between B and WB environments in seedlings composition and abundance per specie. The average of seedlings per month was higher in B while the average of seedlings per specie was similar. The absolute density of E. edulis and other species seedlings varied in time in both environments, showing more seedlings density of the former in B and more seedlings density of the later in WB. When all species were analyzed together, seedling density was different between environments and months. The average of seedlings that emerged and died was higher in B environment. The survival rate varied between environments and in time. We found that E. edulis was the only specie that did not show any demographic limitations between environments. Seed rain did not vary between environments in relation to the specie composition as much as in the seed quantity... (Complete abstract, click electronic access below)

Orientador: Wesley Rodrigues Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T19:16:14Z (GMT). No. of bitstreams: 1 Zaniratto_CristianePatricia_M.pdf: 6906690 bytes, checksum: 61183ae4c09cd06d8858d6ee6aa85be7 (MD5) Previous issue date: 2015 / Resumo: A degradação em florestas tropicais afeta as relações mutualísticas entre plantas e frugívoros, o que é refletido na chuva de sementes. Devido ao comportamento alimentar e à alta capacidade de deslocamento, aves e morcegos frugívoros são importantes agentes no processo de restauração, pois transportam propágulos de fontes bem preservadas para áreas impactadas. Este trabalho avaliou a chuva de sementes zoocóricas em um mosaico fisionômico de restauração de Mata Atlântica no estado de São Paulo, considerando a contribuição de aves e morcegos, bem como a influência de fatores ambientais sobre a chuva de sementes. As sementes foram analisadas quanto ao sistema de dispersão (ornitocóricas e quiropterocóricas), grupo sucessional (pioneiras e não pioneiras) e origem (espécies do plantio e colonizadoras). Também foi comparada a chuva de sementes entre áreas com diferentes fisionomias. A estação chuvosa apresentou maior abundância e riqueza de propágulos, indicando uma maior disponibilidade de recursos para a fauna durante esse período. As variáveis ambientais não explicaram a abundância total de sementes, a abundância de sementes quiropterocóricas e a abundância de sementes pioneiras. Esses resultados foram influenciados por algumas espécies amplamente coletadas em todos os pontos de amostragem, o que dificultou a formação de um padrão. A abundância de sementes ornitocóricas foi explicada por uma relação positiva com a densidade de plantas zoocóricas, sugerindo que essas espécies constitui um fator de atração importante para a avifauna. A abundância de sementes não pioneiras foi relacionada negativamente à abertura de dossel e positivamente à densidade de sub-bosque. A riqueza total e a riqueza de sementes ornitocóricas relacionaram-se negativamente à abertura de dossel. As riquezas de sementes quiropterocóricas, pioneiras e não pioneiras foram relacionadas negativamente à abertura de dossel e positivamente à densidade de sub-bosque. As fisionomias em estágio avançado de regeneração apresentaram maior riqueza na chuva de sementes, embora a abundância não tenha diferido entre as áreas. Tais resultados sugerem que a complexidade estrutural do ambiente um é um fator importante para a chuva de sementes, atraindo mais dispersores. Registrou-se maior abundância e riqueza de espécies ornitocóricas, o que mostra que a avifauna contribui mais para a recuperação da área. As espécies pioneiras também foram mais abundantes e mais ricas. A baixa dispersão de sementes não pioneiras é preocupante, pois indica que dispersores de médio e grande porte não frequentam a maior parte da área de estudo, atrasando o processo de regeneração natural. As espécies colonizadoras apresentaram maior riqueza, embora não tenha havido diferença entre a abundância de espécies colonizadoras e do plantio. Esse resultado mostra que, ao longo dos anos, houve um fluxo de sementes de áreas fontes para as áreas em processo de regeneração. A análise da chuva de sementes na área de estudo permite concluir que a regeneração está ocorrendo espontaneamente, pois o transporte de diásporos existe em todo o mosaico de restauração, entretanto, a maior riqueza e abundância de espécies pioneiras mostram a necessidade de ações de manejo para acelerar a colonização por frugívoros de médio e grande porte, incrementando a chuva de sementes local / Abstract: The degradation of tropical forests affects the mutualistic interaction between plants and frugivores, with reflexes in seed rain. Due to their feeding behavior and high capacity of displacement, birds and bats are important agents in restoration process, because they carry the seeds from well-preserved sources to degraded ones. This work evaluated the zoochorous seed rain in a restoration physiognomic mosaic of Atlantic Forest in São Paulo state, considering the birds and bats contribution, as well the influence of environmental factors on the seed rain. Seeds were analyzed according to their dispersal system (dispersed by birds or bats), successional group (pioneer and non-pioneer) and origin (planted and colonizing species). The seed rain between physiognomies is also compared. The abundance and richness of seeds were higher in the rainy season, which points to a high resource availability to fauna in this period. The environmental variables did not explain the overall abundance, the abundance of chiropterochorous seeds and the abundance of pioneer seeds. These results were influenced by some species largely collected in all sampling points, which made difficult a pattern. The abundance of ornitochorous seeds was explained by density of zoochorous plants, suggesting that these species are an important attraction factor for birds. The abundance of non-pioneer seeds was negatively related to canopy opening and positively related to understory density. The overall richness and the richness of ornitochorous seeds were negatively related to canopy opening. The richness of chiropterochorous, pioneer and non-pioneer seeds were negatively related to canopy opening and positively related to understory density. The physiognomies under advanced regeneration stages had higher seed richness, although the abundance did not differ between areas. These results show that the structural complexity of environment is an important factor to seed rain, by attracting more dispersers. There was a higher abundance and richness of ornitochorous seeds, which shows that birds contributed more to forest recovery. Pioneer species are also more abundant and richer. The low dispersion of non-pioneer seeds is worrying, once suggests that medium and big size dispersers don¿t occur in the most of the study area, delaying the natural restoration process. Colonizing species were richer, although the abundance between colonizing and planted seeds species did not differ. It shows that there was a seed flow from source areas to restored ones over the years. The seed rain analysis allows the conclusion that restoration is occurring spontaneously in the studied area, since transportation of seeds are occurring across all the restoration mosaic. However, the high richness and abundance of pioneer species points to the necessity of management actions in order to accelerate the colonization by medium and large size frugivorous, improving the local seed rain / Mestrado / Ecologia / Mestra em Ecologia

This study created an ecological spatial model, using a geographic information system, to visualize the influence of hydrochory on restoration of the three dominant wetland communities of broadleaf marsh, wetland shrub, and wet prairie across the floodplain of the Kissimmee River. Primary parameters incorporated into the model included floodplain hydrology, seed characteristics of buoyancy and dispersal rates, and species flood tolerance. S²rensen's similarity index, comparing spatial agreement among model output and observed community data, resulted in values of BLM-BB = 0.10, BLM = 0.07, WS = 0.21, and WP = 0.36. The significant discrepancies between modeled and observed community spatial coverage indicated a need for incorporation of more stochastic variables of climatic disturbances, nutrient availability, and soil characteristics. More research on species flood tolerance across smaller spatial scales is also needed, and base data incorporated into the model should also be reliable and consistent if accuracy is to be achieved. / by Stevee Kennard. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Call number: LD2668 .T4 1985 P32 / Master of Science

Thesis (MScEng)--Stellenbosch University, 2010. / ENGLISH ABSTRACT: This project originated when a team of scientists at the Gobabeb training and research and centre observed seed accumulation sites on the slope of sand dunes in the Namib Desert. Seeds that accumulate on the slip face of a sand dune provide food for small desert creatures that in turn attract larger animals, resulting in a small ecosystem on the side of the dune. Since wind is the primary transport of seeds throughout the Namib Desert it is of interest to investigate wind patterns over the dune. In this project it is therefore desired to look at seed dynamics and deposition as a result of near surface wind patterns around a three-dimensional dune geometry using computational fluid dynamics. The project is a joint venture between the University of Stellenbosch and the University of Namibia. This document presents the South African MScEng thesis part. The literature review shows the dominant winds in the Namib Desert to be from the south to westerly direction. Previous studies on air flow over dunes focussed on sand movement and were often limited to simplified two-dimensional geometries and steady state simulations. From these studies the basic flow features associated with dunes can be identified. Lastly, factors that influence particle dynamics around dune geometries are looked at. These particle studies mostly involve the movement of sand rather than seeds but still provide valuable insight. The project methodology is explained and includes the equipment used, the considerations taken into account, the simplifications made as well as the procedure followed when conducting field work and simulations. A section of an actual Namibian linear dune is mapped in order to obtain a geometry for the simulations. Flow measurements are carried out with a wind mast to obtain velocity profile inlet conditions for the simulations. Furthermore, seed sampling is done by the collaborating Namibian team of which the data is used to obtain an effective seed particle model. Lastly, simulations are carried out using primarily OpenFOAM-1.5. The simulations look at general near surface wind patterns, time dependant flow features and particle movement and seed deposition around and on the linear dune. The results show different wind profiles for different wind direction. It is also possible to see how the profile changes as the flow accelerates up the dune slope. Two-dimensional results provide the opportunity to compare results with previous studies as well as to provide the basis for looking at aspects such as differencing schemes, turbulence models and parallel computing before three-dimensional simulations are carried out. The importance of higher order differencing schemes are confirmed in the two-dimensional results. The turbulence models, however, produce very similar results. The results from the two- and three-dimensional results show typical flow features associated with dunes. Transient flow features and separation vortex structures can be identified from time dependant simulations. Furthermore, particle simulations reveal how particles tend to be trapped in the recirculation regions. The conclusions explain how the project objectives were achieved and provide recommendations for future studies related to this project. / AFRIKAANSE OPSOMMING: Die projek het ontstaan toe naforsers areas van saad akumulasie op die hellings van duine in Namibë opgelet het. Hierdie akumulasie van plant materiaal verskaf die voedsel vir klein diere op die duin wat ‘n klein ekosisteem tot gevolg het. Aaangesien die primêre vervoermiddel vir sade in die woestyn wind is beoog die projek om deur die wind patrone oor die duin beter te verstaan die saad verspreiding te beskryf. Die doel is dus om saad verspreiding en akumulasie te beskryf deur die wind patrone te bekyk wat die verspreiding tot gevolg het deur gebruik te maak van numeriese vloei dinamika. Die projek is ‘n saamgestelde projek tussen die Universiteit van Stellenbosch en die Universiteit van Namibië. Hierdie dokument behels die Suid Afrikaanse MScIng gedeelte van die projek. Deur die hersiening van literatuur word daar gesien dat die domineerende wind rigtings as suid tot wes beskryf kan word. Vorige studies wat verband hou met wind vloei oor duine wys dat die meeste op twee-dimensionele eenvoudige geometrië gefokus het met tyd onafhankike simulasies. Dit is egter moontlik om die resultate te gebruik om karakteristieke vloei patrone te identifiseer wat met duin wind patrone geassosieer kan word. Laastens word daar gekyk na die faktore wat partikel beweeging beïnvloed, maar hierdie studies sluit hoofsaaklik sand partikels in eerder as sade. Die motodologie beskryf die toerusting, oorwegings en prosedures wat gevolg is tydens veld werk asook simulasies. Tydens die veld werk is ‘n gedeelte van ‘n Namib lineêre duin gemeet en so gebruik om ‘n geometrie te maak wat vir simulasie doeleindes gebruik kan word. Daar is ook wind meetings gedoen met ‘n wind mas om wind profiele vir inlaat kondisies vir die simulasies te kry. Verder het saad bestudeering die nodige data verskaf om ‘n voledige saad partikel model op te stel wat in die simulasies gebruik kan word. Laastens kyk die simulasies veral na algemene vloei patrone, tyd afhanklike vloei effekte en ook partikel beweging in die vloei veld. Die resultate wys hoe wind profiele verskil wat van verskillende rigtings af waai. Dit is ook moontlik on te wys hoe die wind profiele verander soos die wind versnel teen die duin op. Tweedimensionele simulasies verskaf die geleentheid om te kyk na die effek van verkillende numeriese modelle, turbulensie modelle en ook multi-prosesseerder verwerking. Tydens die twee-dimensionele simulasies is die belangrikheid van hoër orde numeriese metodes besef. Die verkillende turbulensie modelle het egter klein verkille gewys. Alby die twee- en driedimensionele resultate wys karakteristieke vloei patrone wat met duine geasosieer kan word. Verder het tyd afhanklike simulasies gewys hoe wind patrone verander met tyd. Die partikel simulasies wys ook die beweging van partikels deur die wind en hoe dit neig om te akumuleer in die hersirkulasie gebied agter die duin. Die gevolgtrekkings wys dat al die doelstellings bereik is en maak voorstelle vir toekomstige studies wat met hierdie studie verband hou.