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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Conservation of medicinal and aromatic plants of the alpine and subalpine regions of the Swat Valley, Pakistan

Subhan, Fazal January 2010 (has links)
The flora of the Swat Valley is composed of 1550 higher plant species of which a remarkable 350 are medicinally important (out of c. 6000 species with 700 of medicinal value for the whole of Pakistan). The diverse geographic, topographic and climatic conditions in the alpine and subalpine regions of Swat are responsible for its biodiversity richness. The present study on the medicinal and aromatic plants (MAPs) was conducted in the alpine and subalpine regions of the Swat Valley (2007-2009) in order to evaluate their current threats (both anthropogenic and natural), population density, indigenous uses (along with trade importance in the local economy) and impact of climate change. However, the fragility of these highland ecosystems makes this biodiversity vulnerable. The analysis revealed 177 species belonging to 70 families with major families of Rosaceae containing 18 species followed by Lamiaceae 16 species, Asteraceae 15, Ranunculaceae 12 and Polygonaceae with 9 species. The driving forces in the increasing decline of these species were found to be: overgrazing, overexploitation, timber logging, fuelwood collection and agriculture expansion. The root causes behind these driving forces are: the lack of economic development, population pressure, poverty, illiteracy and basic unawareness of sustainability and ecosystem importance. The dominant plant community types in these regions were recorded with their life form (biological spectrum), showing that the flora was of Hemicrypto-therophytic nature with 36.72% (hemicryptophytes) and 14.68% (therophytes). The leaf spectra analysis of these plants revealed that microphyll was dominant (100 species) followed by nanophyll (38 species) and mesophyll (30 species). The palatability analysis revealed that 88% plants were palatable, 34% were highly palatable and 6.6 % were non-palatable. The impact of climate change under current and future scenarios were analysed and indicates that Viola canescens, Fragaria nubicola and Bistorta amplexicaulis would profoundly shift their distribution towards north in comparison to their present distribution while Juniperus communis and Betula utilis have not shown large shifting towards north because of their different climatic needs. Viola canescens would extend whereas Juniperus communis would reduce its distribution. The indigenous knowledge indicates that 93 species belonging to 49 families were of immense importance to the basic health needs of these communities including 19 species used as ethno- veterinary medicines. The market analysis of these plants shows that the most expensive plants are Aconitum heterophyllum, Morchella esculenta and Viola canescens with high demand in the local markets and sporadic exportation to the Middle East, especially to the UAE. The annual tonnage sale of 23 species in the local markets sampled was 196 tonnes per annum with an average amount of 8.52 tonnes. Berberis Iyceum, Saussurea atkinsonii and Viola canescens are the most wanted plants in the area and are the top selling drugs in the local market reaching an annual mean sale of 1 tonne per retailer. Based on the findings of this research, the MAPs of these regions are declining sharply on an enormous scale due to habitat destruction, habitat fragmentation and habitat loss. Government intervention along with the active involvement of local communities is needed in order to ensure sustainable utilisation without risking their local extinction. The study revealed an urgent need to conserve these valuable taxa in situ in the form of national parks, nature reserves and game reserves, and ex situ in the form of botanical gardens, seed banks and other germplasm collections. In addition to the above threat, improper and untimely government policies with poor implementation procedures, compounded by corruption and the illicit influence for resource-use patterns among local and national departments, are further sharply aggravating this decline.
2

Rarity and conservation of Melampyrum sylvaticum

Dalrymple, Sarah January 2006 (has links)
<i>Melampyrum sylvaticum</i> (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 <i>Melampyrum sylvaticum’s</i> 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 <i>M. sylvaticum</i> 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.

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