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Tesi sul tema "Plant conservation"
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1
Dalrymple, Sarah. "Rarity and conservation of Melampyrum sylvaticum". Thesis, University of Aberdeen, 2006. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=128181.
Testo completoAbstract (sommario):
Melampyrum sylvaticum (small cow-wheat) is a hemiparasitic annual of boreal-montane regions of Europe. The Species Action Plan recommended that in addition to protecting extant populations, by 2010 there should be an additional five populations that have been created with the aim of enhancing greater genetic diversity of the species. Consequently this project was set up in order to provide the ecological knowledge required to meet such targets. There are various management options available to conservationists looking to prevent Melampyrum sylvaticum’s extinction from the UK but from the results of this project it is clear that some methods have drawbacks that should preclude their use. Population augmentation with seeds from other populations is not advised due to the risk of genetic ‘swamping’ or outbreeding depression. Seed amplification would avoid these problems but may introduce different complications by artificially promoting certain genotypes within a population. Population expansion by mimicking ant dispersal is recommended as a way of minimizing density dependent mortality in larger populations but is not suitable in smaller populations. Seed translocation to unoccupied sites is therefore, the best option but the exact details of seed-sourcing and sowing should be guided by the results of the Species Recovery Project in order to avoid predicted limitations. The long-term outlook for M. sylvaticum will depend entirely on whether populations can be created that operate as part of a functioning ecosystem (including pollinating and seed-dispersing insects) with enough demographic and genetic stability to survive predicted climate change.
2
Scobie, Andrew Rutherford. "Understanding the causes of reproductive failure in two rare Scottish plants, Linnaea borealis L. and Spiranthes romanzoffiana Cham. and the implications for future conservation management". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until Dec. 21, 2011, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=59437.
Testo completo
3
Baena, Susana. "Remotely sensed solutions for plant diversity conservation". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/51765/.
Testo completoAbstract (sommario):
Global change is happening at a staggering pace and the impact that change is having in the loss of plant biodiversity is unprecedented. The latest reports on the state of the world’s plants indicate that they face intensifying threats and biodiversity loss on a global scale. However, this rapid global change is also bringing extraordinary technological developments to all scientific fields. Earth Observation by Remote Sensing is undergoing a fast expansion and its capacity to monitor and analyse global environmental changes and their impact in biodiversity is ever growing. This research analyses the current and potential role of Earth Observation in the conservation of plant diversity, identifying the latest technological developments with the greatest potential use in this field. Looking into a plant conservation organisation and through a series of case studies covering a range of spatial and temporal scales, this research brings the latest Remote Sensing technology to the plant conservation community. From collecting and processing very high resolution data for local conservation projects to help determine conservation status of a country’s unique ecosystem to tracking and reporting on global plant conservation targets this research demonstrates that Remote Sensing is instrumental for addressing the observation needs of the plant conservation community.
4
Orozco, Barbara Ayala. "Maintaining the drivers of tropical plant diversity : plant disease in conservation practice /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2008. http://uclibs.org/PID/11984.
Testo completo
5
Wong, Kwong-chiu Alfred. "Conservation genetics of Hong Kong wild orchids /". Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2035793X.
Testo completo
6
Ng, Sai-chit. "Hong Kong's rhododendrons : ecology, population genetics and conservation /". Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21482743.
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7
Cheung, W. T. "The conservation of plants in Hong Kong /". View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B3473742X.
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8
Swarts, Nigel. "Integrated conservation of the rare and endangered terrestrial orchid Caladenia huegelii H.G. Reichb /". Connect to this title, 2007. http://theses.library.uwa.edu.au/adt-WU2008.0044.
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9
Vorster, Liesl. "Current status and impact (2004-2015) of indigenous ungulate herbivory on the vegetation of Sanbona Wildlife Reserve in the Little Karoo". Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25523.
Testo completoAbstract (sommario):
Game farming is becoming more popular in southern Africa and the introduction of large indigenous ungulates into confined enclosed areas could alter plant communities and ecosystem processes. This is of particular concern in semi-arid rangelands of the Succulent Karoo where the evolutionary history of grazing is not clear and the compatibility of large herbivores in confined areas remains to be demonstrated. The establishment of Sanbona Wildlife Reserve, a 54 000 hectare private game reserve in the Little Karoo, which converted from livestock farming to game farming, allows an opportunity to study the vegetation dynamics in a confined plant-herbivore system. This study investigates the current community structure and the changes in the floral composition and vegetation structure of enclosed and comparable sites subjected to grazing by large herbivores after twelve years (2004-2015). It also determines the relative effect of grazing and rainfall on the observed patterns. Finally, the implications of these findings for management are discussed. Data from drop-point surveys in fenced (exclosure) and unfenced (grazed) plots in the dominant vegetation types as well as annual and seasonal rainfall totals, stocking rates of herbivores and annual game census information, were analysed. These were used in multivariate ordination techniques, regressions and linear mixed-effects models to determine the communities and their relationship with herbivory and rainfall over time and identify a set of indicator species. The annual game census information was used to determine areas of herbivore preference or 'hotspots' and for the identification of highly-utilised areas. Cluster analysis, using the flexible beta method in PC-Ord, was used to determine the current plant communities. Non-metric multidimensional scaling ordination (NMS) was used to determine the relationship of these communities with the environmental variables and illustrate the trajectories in floristic data. Species were also assigned to plant growth forms and examined as communities and growth form types. The Bray-Curtis distance measures were used to investigate the difference between each treatment over time, within each vegetation community and between treatments. Finally, the effects of rainfall and herbivory were examined using linear mixed-effects models of change over time vs the various potential determinants of change using lmer functions in R. Four communities were identified. These communities corresponded well with to the vegetation type descriptions for Western Little Karoo, Little Karoo Quartz Vygieveld and Renosterveld as described in the National Vegetation Map of Mucina and Rutherford (2006). However, the Western Little Karoo was too broad and two communities were recognised within this vegetation type. The finer scale mapping by Vlok et al. (2005) corresponded relatively well to these communities. Results showed an increase in species richness, abundance and cover over time, with the ungrazed plots experiencing more change than the plots exposed to grazing. Most growth forms exhibited an increase in cover, although low leaf succulents declined in both grazed and ungrazed plots. Medium evergreen shrubs declined in the exclosures and stem succulents declined in the grazed plots. The effects were found in both grazed and ungrazed treatments. In addition, many species which declined in abundance were unpalatable or toxic to herbivores. Because of this, the decline in cover of such species was not attributed to grazing, but was instead interpreted as being a response to other disturbance mechanisms, to competitive displacement and to rainfall events. The low stocking rates in the first five years of the study resulted in there being very little difference evident between the treatments. However, once stocking rates increased from 2008, both species richness and cover increased more rapidly in the ungrazed plots, compared to the grazed plots. An increase in palatable and unpalatable species was observed within both ungrazed and grazed plots indicating that grazing did not change the proportion of palatability classes. However, specific plots in the areas of high animal utilisation were more affected as indicated by the response of cover, species richness and palatable species in these specific plots. This suggests that the grazing pressure may be too high within those areas. The linear mixed-effect model supports the argument that grazing pressure is the dominant driver of the community change within grazed plots. Similarly, the results show that rainfall is the primary driver of the vegetation community in the absence of grazing. Timing, amount and intensity of rainfall can mask these impacts. Thus, the contribution of grazing to vegetation change can probably only be detected by tracking the trends over decades or longer. The use of indicators as a management tool is well documented. In order to identify indicators, a theoretical framework for determining indicators species in the different vegetation communities was created. This was based on the correlation between species abundance and sampling period in the different treatments, which identified species that have significantly increased or decreased over time as a result of the change in land use. Species identified as potential indicators were selected on the basis based on their abundance and ranged in lifespans and palatability. The indicators chosen need to be monitored into the future to confirm their utility as indicators. A small but significant difference between grazed and ungrazed plots suggest that herbivore impact is apparent. Identifying this trend indicates that the monitoring programme is providing a useful tool for assessing the impact of herbivores on an ongoing basis. The recovery process following the withdrawal of domestic livestock from Sanbona was much slower in the grazed plots than in the protected plots. Therefore, for the continued recovery of the vegetation to occur and for there to be a sustained increase in cover, active management of animal numbers needs to take place. The results from this study can contribute to future management decisions on the reserve and form a basis for future analyses.
10
Ong, Laura E. "Conservation of pathogen recognition mechanisms in different plant species". [Bloomington, Ind.] : Indiana University, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3215189.
Testo completoAbstract (sommario):
Thesis (Ph.D.)--Indiana University, Dept. of Biology, 2006.Source: Dissertation Abstracts International, Volume: 67-04, Section: B, page: 1764. Adviser: Roger W. Innes. "Title from dissertation home page (viewed June 20, 2007)."
11
Smith, Wynet. "The use, abundance and conservation of woody species in the Batemi Valley, northwestern Tanzania /". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69667.
Testo completoAbstract (sommario):
The Batemi are an agropastoral group who inhabit a semi-arid area in Northwestern Tanzania. The group lives a traditional subsistence lifestyle and are therefore dependent on the resources that surround them. This study: (1) investigates their use of woody vegetation; (2) studies the abundance and distribution of woody vegetation in the area; and (3) experiments with assigning use values to species and with employing these use values to identify conservation priorities. The Batemi utilize over 100 woody species, in 37 families' and 58 genera, from the environment surrounding their villages for construction, fuel, implements, services, food and medicine. Random sampling and systematic inventories in the valley showed that the most abundant species are Croton dictygamous and Acacia tortilis. Land cover in the area can be classed into three main vegetation types using a polythetic divisive program, TWINSPAN and these types are linked to three habitat types: hillside, plain and riverine. A landcover map for the area was produced from Landsat TM digital data. Based on density of woody vegetation, four categories were chosen for the final map product: thicket, woodland, wooded grassland, and grassland. To establish conservation priorities, use values are assigned based on importance of a use, number of species that can fulfill that use, and the rate of consumption. These values, when compared to abundance, provide a framework for considering conservation priorities. Based on various methods, Acacia mellifera and Haplocoelum folioosum are identified as two species that may require special attention.
12
Dawson, Wayne. "Explaining alien plant invasions using Amani Botanical Garden in NE Tanzania". Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Restricted: no access until June 8, 2010, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26082.
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13
Sharma, Jyotsna. "Mycobionts, germination, and conservation genetics of federally threatened Platanthera praeclara (Orchidaceae) /". free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060142.
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14
Tarrant, Valerie M., e valerie tarrant@deakin edu au. "Melbourne's indigenous plants movement: The return of the natives". Deakin University. School of History, Heritage and Society, 2005. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20061207.113857.
Testo completoAbstract (sommario):
This thesis examines Greater Melbournes indigenous plants movement from the 1930s to the early twenty first century. It demonstrates the important scientific and educational role of the public intellectual, Professor John Turner, and of the Melbourne University Botany School which he led for thirty five years. The case study of the movement within the City of Sandringham and its successor the City of Bayside reveals how the inhabitants of an urbanised are responded to threats to the indigenous trees and wildflowers of their neighbourhood, stimulating botanists to assist them and using political means in order to achieve their conservation objectives. The thesis draws upon a range of local archives, conservation literature and private papers.
15
Cheung, W. T., e 張偉滔. "The conservation of plants in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45013032.
Testo completo
16
Athorn, Marie. "Conservation value of constructed reedbeds". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52317/.
Testo completoAbstract (sommario):
Natural reedbed habitat in the UK has suffered severe declines in the last few centuries. With only 5,000 ha remaining and much of what remains is highly fragmented and degraded. The loss and fragmentation of reedbed habitat in the UK has had a profound effect on the species associated with it. Constructed reedbeds are artificial wetlands dominated by Phragmites australis designed to treat wastewater. They have been widespread in the UK because they are perceived to be a green solution, but their conservation value has never been assessed. This project aims to determine how they contribute to biodiversity. This study surveyed 24 sites, 12 constructed sites paired to 12 natural sites, for small mammals, moths and stem-dwelling invertebrates. Results show that there is no difference between constructed and natural sites. The indication is that constructed reedbeds, despite their small size, young age and contamination, are just as diverse as natural reedbeds. The implications of this for reedbed and wetland conservation are potentially substantial. There are over 1,000 constructed reedbeds in the UK that are just as diverse as their natural equivalents, which could provide connectivity across unsuitable agricultural and urban landscapes.
17
Kreivi, M. (Marjut). "Conservation genetics and phylogeography of endangered boreoarctic seashore plant species". Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514290190.
Testo completoAbstract (sommario):
Abstract
The amount and distribution of genetic diversity are likely to affect the evolutionary potential of a species. When feasible and cost-effective policies for management and monitoring of endangered populations or species are planned, knowledge of the spatial genetic structure and the type of population dynamics is of great concern. In this thesis the genetic diversity and population structures of two endangered arctic plant species was examined on different geographical scales in Northern Europe. The species were Siberian primrose (Primula nutans) and pendant grass (Arctophila fulva), which both grow in a seashore habitat and have similar distribution patterns on the shores of the Arctic Ocean and the Bothnian Bay.
The goal of the present study was to provide basic population genetic information for the study species using microsatellite and AFLP markers. Both markers were used for the first time in these species, and species-specific microsatellite markers were developed during the study. A further aim was to interlink the population genetic processes of the species into distribution patterns at the regional and population levels and to compile a synthesis of the impact of hierarchical spatiotemporal processes and autocorrelation in genetic variation at different levels.
The studies of this thesis provided new information on the diversity and population structure of the endangered study species and new markers that are useful in future genetic studies of primrose species. The diversity of Siberian primrose was low, and there was no dispersal between the study regions. In pendant grass, a relatively high amount of variation was found considering the evident clonal reproduction and gene flow that was detected between populations connected by waterways. The results suggested that both clonal and sexual reproduction are important in this species. On a local scale, pendant grass populations had characteristics of “stepping stone” and classical metapopulation models.
The results indicated that on a long time scale, both species will continue to decline without efficient management efforts. Most critical for the persistence of the species is the conservation of suitable habitats. Translocations could be considered in order to enhance the diversity of existing populations and establish new populations.
By examining the present day structure of Siberian primrose, it was possible to make inferences regarding the colonisation history of the species in the North European area. The current distribution of Siberian primrose seemed to result from a vicariant process that took place after the last ice-age, when the species colonised the area. It spread first to the White Sea area, probably from the east, and subsequently colonised the Bothnian Bay and the Barents Sea in the west. The isostatic land uplift after the retreat of the Eurasian ice sheet uncovered large areas of land from the Baltic Sea basin that previously were under water. These geological changes resulted in the current disjunct distribution of Siberian primrose.
18
Griffiths, Christine Jane. "Conservation and restoration of Mauritian plant communities using taxon substitutes". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.544321.
Testo completo
19
Siegwarth, Mark. "Boyce Thompson Arboretum and the Global Strategy for Plant Conservation". University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/556782.
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20
Ng, Sai-chit, e 吳世捷. "Hong Kong's rhododendrons: ecology, population genetics and conservation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B43894343.
Testo completo
21
Mader, André Derek. "The demography of Acacia stands on the Hluhluwe-Umfolozi Game Reserve". Bachelor's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/24831.
Testo completoAbstract (sommario):
Little is known about the demographics of the genus Acacia in Africa, despite its prominence and the economic and environmental importance of this group. The demographics and species composition of stands of four different Acacia species was investigated in the Hluhluwe-Umfolozi Game Reserve in northern Kwazulu-Natal in order to determine whether stands were self-replacing, or whether other Acacia species were invading them. Soil and stand density as well as the density and composition of the grass layer were investigated in order to determine whether any of these affected Acacia demography and species composition. In three out of four cases, the species whose large size class dominated the stand (known as the "stand species") was found to have a strongly bimodal size class distribution, skewed primarily towards the large size class and secondarily towards the small size class. Other Acacia species in the stands, with few or no large individuals present ("nonstand species") tended to have unimodal size class distributions, skewed primarily towards the small size class and secondarily towards the medium size class. Based on the proportion of small to large individuals, non-stand species are more likely to increase in overall numbers in future, suggesting that the species composition of the stands may be in a state of flux. Few relationships were found between stand density, grass density, grass composition and numbers of small and medium acacias. This could be as a result of differentiation between Acacia species, meaning that they cannot be analysed collectively. Furthermore, sample sizes of individual species may have been too small to analyse individually. Alternatively, it could mean that none of these factors have a significant effect on one another and that other explanations need to be found for the demographics of this genus.
22
Saeed, Auday Esmail. "Integrated design of chemical plants with energy conservation (the design of an energy efficient styrene plant)". Thesis, University of South Wales, 1990. https://pure.southwales.ac.uk/en/studentthesis/integrated-design-of-chemical-plants-with-energy-conservation-the-design-of-an-energy-efficient-styrene-plant(27fb4dfc-5ed8-40ff-a747-c302c43415da).html.
Testo completoAbstract (sommario):
Energy consumption is one of the main areas in the study of chemical process design. It is usually referred to as the critical element that is continuously needed for running a chemical process, and is daily effected by the prices of energy. Therefore, poor designs which are not energy integrated normally lead to less profit due to high consumption of energy. These simple economics are the reason for tackling the area of energy integration in process design. A styrene production process is taken to be the model process for carrying out the design work incorporating the various energy integration techniques. A thorough review of the published work in this subject area was the first step in this research work. This has been followed by calculating mass and energy balances around the overall plant and the individual process steps, so that information about flowrates and energy consumed and released was obtained for the base case. After this all the possible distillation sequence configurations were tested in order to find the sequence that required least energy compared with all the other possible sequences. This step is the first part of integrating the distillation train. The second part considered the heat exchanger network associated with the distillation train and this has been taken in the context of overall process integration. "Pinch technology" was used as an aid for targeting the minimum hot and cold utilities required, designing the heat exchanger network that was compatible with the minimum use of utility and to seek further improvements on the process heat exchanger network which made it capable of recovering even more energy. Utility supplies are designed with respect to the process design, hence the next step considered the interaction between the utility and process design. Thus, the utilities were introduced in a more efficient way, resulting in a better heat exchanger network and increasing the interprocess heat exchange. Finally the steam and power system in the styrene plant was tested in order to determine how much this system had benefited due to the overall efficiency of energy supply and demand.
23
Levy, Foster, e James T. Donaldson. "Morphology, Geographic Distribution, and Conservation of the Southern Appalachian Endemic". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5450.
Testo completoAbstract (sommario):
Taxonomic recognition of Solidago lancifolia (Torrey & A. Gray) Chapman and diagnostic characters used for identification have vacillated among floras and treatments. Fieldwork greatly expanded the specimen base in US herbaria, extended the known range in Tennessee, and identified new occurrences in North Carolina and Virginia. A morphometric analysis of herbarium specimens identified qualitative and quantitative characters unambiguously diagnostic for S. lancifolia. These included the presence of glands on the phyllaries; long, wide-diameter rhizomes; thick stems; and a long pappus on disk florets. Using these characters, an analysis of herbarium specimens corrected widespread misidentifications and showed that S. lancifolia is strictly endemic to a 12-county region encompassing the high elevations (> 1,400 m) in the mountains of southwestern Virginia, northwestern North Carolina, and northeastern Tennessee. Based on the narrow geographic range and small population sizes, prior uncertainty of the taxonomic validity and geographic range of S. lancifolia has been resolved. Consequently, for North Carolina and Virginia, the recommendation is for an upgrade in the conservation status to “Endangered” with a state rank of “S1.” Moreover, the narrow geographic range and small number of populations are consistent with a global rank of “G2” and consideration as a federal Species of Concern.
24
Mosime, Bonolo. "In vitro conservation of selected endangered plant species indigenous to the Cape Floristic Region, South Africa". Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2343.
Testo completoAbstract (sommario):
Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2016.This study focused on optimising four types of in-vitro conservation methods, namely: 1), micropropagation, 2) in-vitro slow growth, 3) seed germination and 4) cryopreservation for selected endangered plant species indigenous to the Cape Floristic Region. It is one of the targets set by United Nations millennium development goals, to integrate different conservation measures in order to preserve plant diversity and mitigate losses of genetic diversity. Therefore this study uses Phalaenopsis hybrids as a trial species that can be studied for the conservation of endangered Disa and Eulophia species through micropropagation and in vitro slow growth. Also conservation attempts on Leucadendron and Mimetes species that occur in the Cape Floristic Region were attemted to increase population densities by increasing germination percentages using smoke. Furthermore, the study attempted to store seeds by assessing different cooling rates for optimising cryopreservation measures for effective conservation. The use of tissue culture to increase propagules especially critically endangered species in South African has proven to be feasible. For the trial hybrids, shoot and protocorm explants of Phalaenopsis Psychosis Pink X P. No. 1; P. Large white X P. Large pink; P. No. 1 X P. Large pink; P. Mini pink X Brighton belle; and the P. aphrodite formed clusters of protocorms and shoots when cultured on ½ strength MS media supplemented with 10, 20 and 30gL-1 banana extract or ½ strength Murashige and Skoog, (1962) (MS) media supplemented with peptone. Continuous protocorms formation could therefore be obtained by culturing endangered Disa and Eulophia shoots and protocorms on banana containing media. Plantlet conversion from somatic embryos produced on 10gL-1 banana extract enriched media was successfully achieved on ½ strength MS supplemented with 20gL-1 sucrose and no plant growth regulators in the medium. However, optimum rooting was achieved on ½ strength MS supplemented with 30gL-1 of banana extract and this medium yielded the highest survival percentages for plantlet acclimatisation. Furthermore, ½ strength MS supplemented with 1gL-1 of peptone served as a stimulant for shoot development and protocorm formation. When coupled with banana extract at all stages of development, regeneration and rooting were enhanced.
25
Wheat, Nicola M. "Patterns of parasitism and emergence in the gall midge Dasineura Dielsii (Diptera: Cecidomyiidae) : a biological control agent of Acacia cyclops in South Africa". Bachelor's thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/25722.
Testo completoAbstract (sommario):
Acacia cyclops A. Cunn. ex G. Don is an invasive alien plant that invades fynbos and coastal dunes. Several acacia species are grown commercially in South Africa and this has limited biocontrol agents to those that reduce only reproductive capacity. Dasineura dielsii was released in 2002 as a biocontrol agent for A. cyclops. This gall-forming midge destroys inflorescences and prevents seedpods from forming, but allows continued harvesting. Insects overwinter as larvae within their galls. This study examined the levels of parasitism experienced by dormant D. dielsii larvae, as well as the trigger that causes them to break dormancy. Gall clusters were sampled over autumn and early winter, and were dissected to determine occupancy. The effects of temperature and light on dormant larvae were also examined. Observations showed that as the season progressed, more D. dielsii larvae entered dormancy. At the same time, a greater proportion of dormant larvae were parasitized. Parasitism was highest, at 18.5%, at the end of the study period, but this level of parasitism is not enough to reduce the biocontrol power of D. dielsii. A positive relationship between mass of gall clusters and the number of galls they contain was established. Larval dormancy could not be artificially broken by either light or temperature, and it appears that neither factor alone can trigger a break in dormancy.
26
Lam, Chi-chi Chris. "Tree stories of Hong Kong". Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B24534444.
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27
Irmak, Suat. "New irrigation-plant production system for water conservation in ornamental nurseries". [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE1001153.
Testo completo
28
Sari, Ugur. "Pollen polymorphism in Magnoliaceae and conservation of plant male germline regulators". Thesis, University of Leicester, 2015. http://hdl.handle.net/2381/37923.
Testo completoAbstract (sommario):
In flowering plants twin sperm cells are produced by the male gametophyte to enable double fertilization, which is of vital importance for plant fertility. The process of male gametogenesis depends upon relatively poorly understood mechanisms of gamete cell production, but the male germline-specific R2R3 MYB transcription factor DUO1 is an essential factor in germ cell division and gamete differentiation in Arabidopsis. One major objective of the thesis was to assess the validity of Brewbaker’s evidence that Magnoliaceae possess exclusively bicellular pollen at anthesis. This analysis provided conclusive evidence of the coexistence of polymorphic (bicellular and tricellular) pollen in Magnoliaceae species. Further, the maturation of pollen under increased temperature regimes can significantly accelerate the rate of generative cell division in M. grandiflora. A second major aim was to identify sequence and functional conservation of DUO1 orthologs genes in angiosperms and bryophytes. This study provided further evidence that a supernumerary lysine residue in the DUO1 MYB domain is widely conserved and the sequences and expression of two DUO1 orthologs from moss (Physcomitrella patens) were validated. Arabidopsis, tomato and rice DUO1 orthologs were shown to transactivate Arabidopsis DUO1 target promoters. The expression of angiosperm DUO1 orthologs were able to complement the generative cell division and genetic transmission defects in duo1 mutants, demonstrating conservation of function of DUO1 orthologs in Arabidopsis. The final objective was to investigate the functional conservation of DAZ1/DAZ2–related proteins in other angiosperms. The AtDAZ1 orthologs from Brassica rapa (BrDAZ1) and tomato (SlDAZ1) were able to partially rescue the division and transmission defects of daz1/daz2 double mutant pollen, allowing daz1/daz2 homozygous lines to be established harbouring heterologous DAZ1 transgenes. Collectively, these results show conserved functions for both DUO1 and DAZ1/DAZ2 orthologs, highlighting the important role of the transcriptional network controlled by these male germline-specific regulators in from angiosperms.
29
Kesler, Herbert C. Guyer Craig. "Conservation of a Florida endemic carnivorous plant Godfrey's butterwort (Pinguicula ionantha) /". Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/KESLER_HERBERT_1.pdf.
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30
Oikawa, Junko. "Future role of living plant collections in gardens for biodiversity conservation". Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314314.
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31
French, Graham Christopher. "Conservation genetics of the critical plant genus Euphrasia L. in Britain". Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/13856.
Testo completoAbstract (sommario):
Recent national and international conservation legislation has led to an increased focus on ‘prioritised species lists’ for the allocation of conservation resources. However, prioritised species lists become problematic when there are difficulties in species delimitation. One particularly complex group accounting for the majority of these problems is Euphrasia. The goal of this thesis is to use molecular markers to evaluate taxon limits and evolutionary processes in British Euphrasia to clarify the most appropriate approach for conservation. The results show that the major reproductive barrier in the group corresponds to ploidy level, with AFLP and chloroplast data both significantly differentiated between diploid and tetraploid species, although occasional gene flow via inter-ploidal hybridisation appears to contribute towards diversification of the diploid group. The genetic data support the current species level taxonomy for the diploid but not the tetraploid species, where a considerable overlap between taxa was detected. The chloroplast data detected four discrete lineages, the distribution of these among species suggest at least three allopolyploid events in the formation of the tetraploid taxa, within which distinct ecological groups occur. Variation in the breeding system was detected at the intra- and inter-specific levels and estimates of the inbreeding coefficient showed a strong correlation with flower size and support the importance of multiple shifts in breeding system as contributing towards the overall diversification within the group. Given the lack of clear species limits in the tetraploid group and the dynamic nature of Euphrasia evolution, a change from a species- to process-based conservation approach is recommended. This charge include recognising the importance of progenitor taxa, and ecological and morphological diversity, and a decrease in the importance presently given to individual named endemic taxa.
32
Philpott, Megan. "The Genetic Consequences of ex situ Conservation of Exceptional Plant Species". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535467395352645.
Testo completo
33
Montanari, Irene <1969>. "Irrigation and drainage canals role for plant diversity and nature conservation". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9955/1/MONTANARI_IRENE_TESI.pdf.
Testo completoAbstract (sommario):
Aims: With this research, we wanted to investigate and promote the conservation of biodiversity in the network of drainage canals of the Po Valley
Study area: The canal network of Bologna plain, long more than 1150 km (Po Valley, North Italy)
Methods: In Chapter II we analyzed the geographical patterns that characterize our transects, the land use of their upstream basins, the water quality at the closure points of their river basins. In Chapter III we described the plant communities with some ecological information and we also tested the effect of the canal size on the plant communities. In Chapter IV we described the relation beetween some functional traits of the plant species sampled and some environmental parameters
Results: A total of 272 species were sampled in 118 transects. The plant communities of the drainage canals have been found to have a significant influence: the geographical pattern "proximity to protected areas", the class of land use "agrozootechnical settlements", and some water parameters. The analysis of the parameter "canal depth" indicated a significant distinction between small and large canals based on plant communities. The functional composition of the plant communities was affected by the bank aspect, the inclusion/exclusion from the protected areas and the upstream basin land uses. Moreover, the functional groups of species responded differently to environmental drivers, water quality gradients and were influenced by a combination of environmental stresses
Conclusions: This research confirms the key role of the canals network in sustaining the plant richness in oversimplified landscapes. Considering the fragility of the floodplains and the global warming that is taking place, it is necessary to rethink the role of irrigation canals and their plant communities in the near future. This work reinforces the belief that long-term sampling plans and greater knowledge about canal management practices are needed
34
Kriticos, Darren John. "Landscape ecology and the management of remnant native vegetation : a case study in the Murray Mallee using a geographical information system /". Title page, table of contents and abstract only, 1992. http://web4.library.adelaide.edu.au/theses/09ENV/09envk92.pdf.
Testo completo
35
Tokura, Wataru. "Understanding changes in plant productivity using EVI satellite data in Tswalu Kalahari Reserve". Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20933.
Testo completoAbstract (sommario):
In the arid African savanna, the limited availability of water strongly affects plant productivity, but other key drivers of vegetation dynamics, such as herbivory and fire, are usually considered to have a relatively minor impact. The main purpose of this study was to characterise the spatial and temporal pattern in plant productivity in the 100 000 hectare Tswalu Kalahari Reserve (TKR) in the semi-arid Northern Cape and relate the observed changes to potential drivers using medium spatial resolution of MODIS Enhanced Vegetation Index (EVI) time series data (16 day, 250 m) from 2000 to 2015. The time series of EVI for the past 16 years in TKR presented a highly seasonal pattern which fluctuated between years. A composite of annual small integrated value of EVI images highlighted spatial and temporal heterogeneity of plant productivity in the area. The EVI value was mainly influenced by rainfall and effect of fire and herbivory was considered to be minor. These observations confirmed the extreme variability of plant productivity in the drylands in the summer rainfall region of South Africa. Additionally, most of the values concerning the phenometrics of EVI differ significantly among vegetation types. This suggests that the structure and function of the vegetation determine plant productivity as well as their being a possible effect of soil property and reflectance. The trend in plant productivity computed by residual trend analysis (RESTREND) detected a significant positive trend in plant productivity in the east and south west of TKR, which overlapped with shrub-dominated vegetation, providing evidence for possible ongoing bush encroachment in these areas. On the other hand, a negative trend was detected in some locations in the west. The data generated from MODIS EVI and the small integrated value of EVI using TIMESAT produced biologically interpretable results. However, the correlative relationship between the EVI derived from Landsat Operational Land Imager (OLI) and plant cover estimated in the field was poor or not significant and needs to be examined further.
36
Contreras, Toledo Aremi Rebeca. "A crop wild relative conservation strategy for Mexico". Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8637/.
Testo completoAbstract (sommario):
There is an extensive diversity of crops and their wild relatives in Mexico, which are distributed throughout the country. Crop wild relatives (CWR) play a special role for present and future food security strategies: they represent a potential source of variation for the domesticated species, contributing to the genetic improvement of these crops. However, the effects of climate change, among other threats, are reducing significantly this biodiversity. The purpose of this study was to analyse the diversity of wild relatives of the most important crops in Mexico as a basis for the development and implementation of a national conservation strategy for these genetic resources. The methods involved the identification of priorities and creation of a national CWR inventory, in situ and ex situ gap analyses at taxon and ecogeographic levels, the evaluation of the impacts of climate change, threat assessment and predictive characterisation. Applying these methods, 310 CWR taxa were identified as priorities and recommendations for immediate in situ and ex situ conservation actions were made to ensure their representativeness under current and future climatic conditions. All these components contribute to the systematic active long-term conservation of priority CWR diversity in the country and enhance their sustainable utilisation thus helping mitigate the threats to Mexican agrobiodiversity and global food security.
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Kashimshetty, Yamini. "Population growth and genetic diversity dynamics of modeled conservation methodologies for threatened plant species". University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1468512768.
Testo completo
38
Nam, Kam-shing, e 藍金成. "Conservation of Hong Kong wild orchids by leaf tip culture". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31212591.
Testo completo
39
Yantis, James Hugh. "Vegetation classification and the efficacy of plant dominance-based classifications in predicting the occurrence of plant and animal species". Diss., Texas A&M University, 2005. http://hdl.handle.net/1969.1/4165.
Testo completoAbstract (sommario):
One strategy for conserving biodiversity is to select large-area preserves that complement each other so the maximum number of species is conserved. Estimates of biodiversity and complementarity are needed for optimum selection of preserves. Comparisons are made in part by defining and mapping vegetation associations under the assumption that candidate areas with no associations in common likely have high complementarity. Conversely, areas with many associations in common have low complementarity. Vegetation associations are often distinguished on the basis of the dominant plant species. Associations with markedly different dominants (e.g., evergreen and deciduous trees) are expected to indicate high complementarity. In this study I evaluated the complementarity of an evergreen forest and a deciduous forest. I also evaluated a dichotomy of subsoil texture. I compared 6 groups of species: (1) woody plants (Dicotyledonae), (2) birds (Aves), (3) small mammals (Mammalia) plus herptiles (Amphibia) and (Reptilia), (4) beetles(Coleoptera), (5) ants (Formicidae) plus velvet ants (Mutillidae), and (6) spiders (Araneae). I made the comparisons using canonical correspondence analysis (CCA), redundancy analysis (RDA), logistic regression, and 3 indices of biodiversity. In this study the species of dominant tree was more strongly associated with the distribution of species than was soil texture. Dominant tree and soil texture used together greatly improved the association with the distribution of species. The association defined by the dominant evergreen tree was not different than the association defined by the dominant deciduous tree, based on the criteria that an association is defined as having a Jaccard similarity index between 0.25 and 0.5. Similarities >0.5, as in this case, are too similar to be an association and are termed a subassociation. Evergreen forests and deciduous forests do not necessarily have high complementarity. Different dominant plant species do not necessarily define different associations. Dominant plant species are not necessarily useful in defining associations or higher-level classifications.
40
Angoh, Siow Yan Jennifer. "The birds, the bees and Erica: vulnerability of plant-pollinator communities in fragmented fynbos landscapes". Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20996.
Testo completoAbstract (sommario):
Habitat fragmentation has been identified as a major cause of pollination mutualism collapse that can eventually impinge on plants' reproductive success (e.g. through pollen-limitation). Agriculture, timber plantations, invasion by alien trees and the urbanisation of the southern Cape lowlands have transformed and fragmented large parts of the former distribution range of many Erica species. Recent evidence suggests that in the Fynbos biome, small remnants of natural and disturbed vegetation are likely to display depauperate plant communities. In the present study, it was found that Erica species richness declined significantly as patch size decreased. Limited nectar resources available on those small 'islands' might not be enough to attract essential bird and insect pollinators. Insect-pollinated species were more impacted by reduced patch size than the bird-pollinated ones. Further investigation using Erica discolor showed that for this widespread ornithophilous species, pollination mutualism still occurred in smaller fynbos patches. These findings stressed the importance of conserving small fragments for maintaining remnant plant populations, which can act as reliable food sources for avian pollinators. In addition, to cope with the effects of pollen limitation, highly resilient plant species have evolved and adopted different compensatory mechanisms. From a short-term perspective, adopting compensatory reproductive strategies (e.g. autonomous self-pollination, vegetative growth, and generalised pollination systems) could reduce dependence on specific pollinators and increase the chances of a species being able to persist through a period of low-pollinator abundance. The prevalence of autogamy and geitonogamy as alternatives to xenogamy was assessed in six different obligate seeder Erica species in the eastern coastal part of the Cape Floristic Region. Despite the long history of plantation-based timber production that fragmented the study area, and the subsequent possible pollinator loss, none of the species analysed in this study have adopted autonomous self-fertilisation as a response mechanism. Erica sessiliflora was the only species that showed a high compatibility for self-pollen. The species under investigation in a breeding system conducted here were also incapable of vegetative propagation and were plants targeting specific animal taxa (e.g. birds or insects) for successful pollination. Having limited compensatory mechanisms, further degradation of their habitat and weakening of their ecological interactions could be extremely detrimental to these Erica species' reproductive success.
41
Colvin, Wesley I. "Linking invasive plant management, conservation, and restoration on Santa Cruz Island, California /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.
Testo completo
42
Mitchell, David Norman. "The plant ecology and conservation of magnesian limestone sea cliffs, County Durham". Thesis, University of Sunderland, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295771.
Testo completo
43
Hartter, David L. "Understanding consumers' ornamental plant preferences for disease-free and water conservation labels". Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/34538.
Testo completoAbstract (sommario):
Product labeling is increasingly used as a tool to differentiate products with public and private benefits that cannot be readily evaluated by a consumer at the time of purchase. Our research investigates how a labeling program may be applied in the sale of ornamental plants to address two key issues; plant disease and irrigation water use. A choice modeling survey was utilized to estimate consumersâ willingness to pay a premium for six ornamental plants with disease-free and/or water conservation certification labels. The results of the mixed logit models show consumers are willing to pay a premium for plants certified as disease-free and/or produced with water conservation practices. The results strongly suggest producers can recoup some of the costs of implementing water conservation measures such as water recycling and disease control measures amid regulatory and drought concerns. Our research also investigated consumersâ preferences for multiple third party certifying authorities and whether preferences for the labels varied among consumers. The results showed ornamental plant consumers did not reveal a preference for a particular certifying authority. The results are mixed as to whether willingness to pay for the labels varies among respondents. We show willingness to pay does vary among respondents for three of the plant models indicating preference heterogeneity.Master of Science
44
Everard, David Alexander. "The conservation status of some unique plant communities in the Eastern Cape". Thesis, Rhodes University, 1986. http://hdl.handle.net/10962/d1007497.
Testo completoAbstract (sommario):
In response to a growing concern over the rising rates of extinction of the world's plants and of habitat destruction, studies of Southern African threatened plants were initiated in the 1970's. These studies, which have largely concentrated on Western Cape flora, led to the publication of "Threatened Plants of Southern Africa" by Hall et al., 1980, which attempted to list as many threatened or possibly threatened species as possible. It was however marred by a lack of recent herbarium records and detailed studies from many parts of the region, the Eastern Cape being one of these. In order to extend these detailed studies to gain a clearer picture of the numbers of threatened species in the Eastern Cape and evaluate the conservation status of Eastern Cape vegetation this project was initiated. Initially lists of possibly threatened and endemic taxa of the Eastern Cape were compiled from various sources. These listed taxa were then checked against herbarium records, all available information being filled onto index cards for filing purposes. This paper-based filing system was then transferred into a computer-based data bank to facilitate the efficient storage and retrieval of information. Results from this data bank show that there are 662 variously threatened plant taxa in the Eastern Cape, many of which fall into temporary categories which need to be clarified by investigation in the field. Primarily based on the above results, a table ranking the various vegetation types into an order of priority for investigations about conservation requirement was developed.Subtropical Thicket was found to be the vegetation type in most need of investigation and so an extensive phytosociological survey was carried out in the Valley Bushveld which forms the major portion of Subtropical Thicket in the Eastern Cape. Twelve sites were sampled for floristic and environmental variables along a rainfall gradient of between 300 mm yr⁻¹ and 1 000 mm yr⁻¹ and along a longitudinal gradient from the Buffalo River in the east to the Gamtoos-Kromme complex in the west. Floristic data W(re analysed using multivariate techniques of classification and ordination. A classification by two-way species indicator analysis revealed the Valley Bushveld to consist of two orders of thicket, the Kaffrarian Succulent Thicket containing the two suborders, Inland Succulent Thicket and the Coastal Succulent Thicket and the Kaffrarian Thicket containing Coastal Kaffrarian Thicket and Inland Kaffrarian Thicket. Ordina tion by detrended correspondence analysis also grouped sites according to these vegetation categories in a sequence along one axis, to which the rainfall gradient could be related. Variables such as diversity indices, numbers of endemics, numbers of threatened taxa and structural features were also extracted from the data and these were correlated with environmental variables by multiple regression analysis. Species richness and the percent woody component w\!re positively correlated with rainfall while endemism and percent succulent component were strongly negatively correlated with rainfall. Most of the other relationships were explained by interrelationships with rainfall. Finally the sites were evaluated according to floristic criteria indicative of conservation value. The Coastal Succulent Thicket appeared to have the highest conservation value mainly owing to high endemism, while Inland Kaffrarian Thicket was also important as it supports a high number of species. The thickets with high conservation value are therefore the thickets of coastal areas in the western parts of the Eastern Cape which receive a low rainfall and the thickets which receive a rainfall in excess of 800 mm.KMBT_363
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Williams, Sophie J. "Improving plant conservation interventions through a better understanding of human decision-making". Thesis, Bangor University, 2013. https://research.bangor.ac.uk/portal/en/theses/improving-plant-conservation-interventions-through-a-better-understanding-of-human-decisionmaking(8bc894f9-329e-4f42-8f96-514eced01856).html.
Testo completoAbstract (sommario):
The threats to biodiversity are predominantly a result of human behaviour. Conservation interventions, from policy formulation to environmental education, often aim to foster behaviour change. But further research is needed to explore the mechanism of behaviour change in a conservation context and what interventions influence behaviour at different scales - from encouraging institutional adoption of conservation policy, to the determinates of household level decision-making. This is particularly important for plant conservation; with more than a quarter of plants species threatened, urgent action and changes in human behaviour are needed to reduce the continuing loss of plant diversity. The purpose of my first chapter is to assess the implementation of an international plant conservation policy and identify what factors influence policy uptake. I examined how and why botanic gardens have responded to the first phase of the Global Strategy for Plant Conservation (GSPC). I surveyed 255 botanic gardens in 67 countries and carried out in-depth interviews with five gardens in five countries. I highlighted how wider policy dissemination is needed to increase global implementation, with particular focus on influencing younger global north gardens and older global south gardens. I identified environmental education as a priority by many botanic gardens and show policy targets related to sustainable plant use are often neglected. I then assessed the effectiveness of education and training programmes implemented by botanic gardens in two different contexts. I first investigated the influence of UK botanic gardens on visitors’ conservation knowledge, environmental attitudes and behavioural intentions. I surveyed 1054 people in five botanic gardens in the UK. A botanic garden visit has no impact on conservation knowledge or behavioural intention but environmental attitude was more positive when people were leaving the botanic garden than on entering. I found no relationship between attitudes and behaviour. Secondly I assessed the effectiveness of targeted training programmes as an approach to encourage behaviour change. I investigated a training programme based at Belize Botanic Garden aiming to encourage cultivation of the over-harvested palm Chamaedorea ernesti-augusti. I surveyed 49 untrained and 38 trained individuals and found the training increased technical knowledge and participants’ self belief, resulting in uptake of cultivation. However, access to seeds was highlighted as a potential barrier to cultivation. Future training programmes may need to consider practical barriers as well as improving technical knowledge, to encourage adoption of cultivation. Finally, I evaluated the effectiveness of different policy interventions to encourage behaviour change at the household level. Using data from the cultivation and harvesting of C. ernesti-augusti, I created a bioeconomic model to identify policies capable of influencing individual decision-making and interventions likely to encourage people to change from harvesting to cultivation. Although schemes to encourage cultivation maybe an appealing conservation intervention, I have suggested caution in assuming that people will readily adopt cultivation of wild harvested species, or that this would necessarily reduce impacts on wild populations. My research provides new insight into the predictors of human behaviour. I illustrate that behaviour may not be solely predicted by attitudes and I show additional behavioural determinants, such as knowledge and self-belief are likely to impact changes in behaviour. This thesis provides new knowledge about the factors determining human behavioural responses to conservation interventions. In this thesis I have discussed how different disciplines provide valuable insight into the process of behaviour change and also highlighted the limitations of each approach. I suggested that conservation science would benefit from further combining approaches from different disciplines to improve the implementation and effectiveness of plant conservation interventions.
46
Bagchi, Anita. "Plant and animal science in ancient India : perspective, attitude and conservation measures". Thesis, University of North Bengal, 2009. http://hdl.handle.net/123456789/1529.
Testo completo
47
Rivers, Malin C. "Range-wide analysis of the spatial distribution and genetic diversity of Delonix s.l. (Leguminosae) in Madagascar : enhancing herbarium-based conservation assessments". Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2097.
Testo completoAbstract (sommario):
Despite their ecological and economic importance, the majority of plant species and their conservation status are poorly known. Only 4% of plants have been assessed globally and listed on the IUCN Red List of Threatened Species; and without plant conservation assessments, many plant species will not feature in conservation planning. Herbarium collection information can significantly increase the number of plant conservation assessments. Thus, the aims of this thesis were: (1) to investigate how the quality of herbarium-based conservation assessments can be optimised; (2) to assess the extent to which herbarium-based conservation assessments reflect the reality on the ground; and (3) to scientifically validate genetic and spatial underpinning of IUCN criteria. Preliminary range-based assessments of the Leguminosae of Madagascar achieved a result consistent with the final conservation rating for over 95% of species when using up to fifteen herbarium specimens. Bioclimatic modelling of range shifts based on future climate change predicted that, in the worst case scenario, up to one third of endemic Leguminosae in Madagascar will be threatened with extinction over the next 100 years. An analysis of the population structure of species of Delonix s.l. (Leguminosae) showed that combining spatial analysis with population genetic data provides a more complete picture of landscape-level population dynamics and the impacts on conservation status. Moreover, range-wide genetic analysis of AFLP markers for four species of Delonix demonstrated a genetic basis for IUCN categories distinguishing between threatened and non-threatened species. Although genetic data are currently not often incorporated in conservation assessments, they are crucial in making accurate management decisions and creating effective action plans for conservation. Only by using all available scientific resources can informed conservation decisions be made and the survival of plants and their associated ecosystems be ensured.
48
Wong, Kwong-chiu Alfred, e 黃廣潮. "Conservation genetics of Hong Kong wild orchids". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31221920.
Testo completo
49
Adams, Graham R. "The management of remnant native vegetation in heritage agreement areas /". Title page, table of contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09ENV/09enva213.pdf.
Testo completo
50
McGrath, Kate. "Phylogeography and population genetics of two forest endemic mosses in the Cape Floristic Region". Bachelor's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/26502.
Testo completoAbstract (sommario):
Different histories for forests in Southern Africa have been hypothesized from vegetation biogeography and pollen analysis. However, the history of forests is still controversial. Phylogeography uses gene genealogies to infer history of distributions. Two forest endemic moss species were sampled: Leptodon smithii; and Neckera valentiniana. Two gene regions were used, trnLF (chloroplast genome) and ITS1 (nuclear genome). Neckera valentiniana showed no variation from the populations sampled. Results from Leptodon smithii based on the trn and ITS region suggest that forests once were widespread, but then became fragmented. Dispersal corridors still exist between Southern Cape populations and Western Cape populations.