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1

Gerber, Nicolas Economics Australian School of Business UNSW. "Biodiversity measurement, species interactions and sustainability". Awarded by:University of New South Wales. School of Economics, 2006. http://handle.unsw.edu.au/1959.4/26796.

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Throughout the last two decades, biodiversity has been increasingly acknowledged as a valuable asset. However there are numerous challenges to managing the asset. Firstly, there is no universally accepted measure of biodiversity per se. As a consequence, rather than measuring the intrinsic value of biodiversity the focus has typically shifted to valuing biodiversity services. Secondly, biodiversity issues should not be considered in a vacuum, but rather alongside general natural resource management problems. Conservation agencies and regulators alike would greatly benefit from more transparent biodiversity targets for conservation policies and natural resource management. This thesis makes a number of contributions to meet these challenges including measuring biodiversity, modelling diverse ecosystems and considering biodiversity outcomes in the management of an environmental resource. To value biodiversity, it is essential to measure it. Focusing on pairwise genetic dissimilarities at the species level, this thesis develops two models for measuring biodiversity. An axiomatic diagnosis of the existing and new measures is presented. This comparison suggests that the adequate biodiversity measure depends on the context. The diversity measures describe the biodiversity catalogue available at a given point in time. Modelling biodiversity is important for forecasting the impact of conservation decisions and understanding the future value of biodiversity. The importance of each species, however, depends on its role in the ecosystem as well as its genetic diversity. The interactions between species are therefore investigated and described, using a new model built around CES production functions. Three existing models based on predator-prey equations are extended to the multi-species case. These interaction models provide the necessary link for biodiversity maintenance over time. The four models are compared using simulations and an axiomatic approach. This approach shows that the new model performs well, offers the flexibility required to describe different types of ecosystems and is less data intensive. Finally, a case study of natural resource exploitation is presented, illustrating the idea that biodiversity loss can have direct economic implications in natural resource management. The model shows the impact of market structures on the extraction path of the resource and the distribution of the resource rent.
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Bush, Glenn K. "The economic value of Albertine Rift Forests : applications in policy and programming". Thesis, University of Stirling, 2009. http://hdl.handle.net/1893/2309.

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The objective of this thesis is to quantitatively understand the economic performance of protected area management strategies for forest and biodiversity conservation. Examples such as integrated conservation and development and eco tourism are assessed in terms of their ability to deliver on welfare benefits to local communities, and an assessment of the opportunity costs of forest conservation as a land use strategy. In addition the contribution of forest conservation in protected areas can make to poverty alleviation and economic development is also examined. The geographical focus of this study is the Albertine Rift region of East and Central Africa, stretching north from the southern end of Lake Tanganyika through the spine of Africa to the northern end of Lake Albert. The Albertine Rift is one of Africa’s most important landscapes for the conservation of forests and biodiversity. The overarching objective is addressed using a series of case studies empirically valuing the opportunity costs of conserving forests in a selection of sites in the central part of the Albertine Rift. The success of conservation is most often measured against progress in reducing habitat or species loss and not often in terms of the contribution of the protected area to poverty alleviation and local economic development. Achieving improvements of conservation strategies in the social dimension requires objective evidence on their effects. Economic valuation of protected area resources provides a quantitative means of assessing the promise and performance of conservation policies in achieving welfare benefits to local communities. This thesis provides three case studies each addressing current valuation and social issues in conservation and sets them in a context of managing protected areas in the broad dynamic setting of poverty alleviation and economic growth from a developing economy perspective. In addition two of the empirical studies are as concerned with methodological enquiry and the performance of novel environmental economic valuation techniques, such as the contingent valuation and choice modelling approaches, as the application of results to conservation questions. The empirical studies show that the benefits to local households and communities from their local forests may be greater than at first perceived. Across all protected area categories, biomes and income groups, households derived significant amounts of their overall income from their local protected area with large proportions of the value of goods harvested from forests being consumed in the home. Amongst income groups high income households often appropriated a greater share of the value of forest goods. There was no significant difference found between the household consumption and the sale of protected area products between income groups. The findings indicate that imposing reductions in forest use may increase poverty amongst local people whilst increasing household income will not necessarily reduce forest exploitation. This indicates that community conservation and integrated conservation and development programmes must target the poor forest adjacent households more actively to ensure poverty alleviation, whilst providing improved protection and law enforcement for effective conservation. It is also shown that biodiversity conservation can have an economic return through mountain gorilla eco-tourism. Findings show a disparity between what constitutes eco-tourism and the real values of tourists towards biodiversity conservation and local social benefits from protected areas. Despite showing a high marginal utility for biodiversity conservation, consumers are unwilling to pay for local community benefits from tourism as part of the permit price to view gorillas. Clearly the link between successful conservation and the welfare status of local communities is not sufficiently established in the minds of consumers to influence their spending decisions. The challenges of effectively mobilising communities to protect biodiversity are discussed in the context of the variable impacts of integrated conservation and development programs over the last three decades. Direct payment payments for conservation services schemes are discussed as an innovative tool to add to the gamut of community approaches currently on offer. Payments for conservation schemes are viewed with cautious optimism in terms of their possibility for success. Despite their allure of being more economically and socially efficient at achieving welfare and conservation objectives, given the complex nature of any society, no less research in to social and economic dynamics of protected area use by local communities would be needed to ensure success of such schemes. However, the overwhelming majority of benefits form protected areas are tied up in ecosystem services values. Mechanisms to generate funding and distribute payments for these benefits in terms of offsetting the local opportunity costs are essential to change local behavior and reduce forest degradation and destruction.
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Moran, Dominic. "Investing in biological diversity : economic valuation and priorities for development". Thesis, University College London (University of London), 1997. http://discovery.ucl.ac.uk/1317651/.

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By all informed scientific accounts the world's biological diversity is currently in a critical condition. Biodiversity is vital for the continued existence of the global biosphere and, by extension, human wellbeing and development. It is inconceivable that a discipline predicated on the issues of scarcity and choice has nothing to contribute in terms of an understanding of either the causes and consequences of biodiversity loss, or in proposing solutions to the crisis. This thesis examines some of the economic parameters of the issue. Alongside the acknowledged root problems of market and institutional failure lies the question of economic valuation. Valuation of biodiversity puts conservation on a more level playing field with the economic forces which threaten its demise. Provided economic values can be appropriated (i.e. converted to flows of real economic resources) it becomes worthwhile for countries to invest in valuable biological assets. But the practice of economic valuation and the quantification of biodiversity are in their infancy and the complexity of the latter hinders the precise application of the former. Much of this thesis focuses on the use and development of the contingent valuation method (CV) as a flexible approach to valuing biodiversity. The method has a useful role to play in resource allocation, and, for valuing biological resources. Faced by the irreducible complexity of life which is the essence of biodiversity, CV does have its limitations. It is possible to conclude that existing valuation methods are a vital part of a "holding operation" alongside other surrogate approaches to setting priorities for global conservation. Nevertheless, the development of an interface between economic (preference-based) values, and biological values, which together can comprehensively inform conservation decisions remains the objective for the future.
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Crook, Carolyn. "Biodiversity prospecting agreements evaluating their economic and conservation benefits in Costa Rica and Peru /". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58978.pdf.

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Omokanye, Akim Tunde, University of Western Sydney, of Science Technology and Environment College i Centre for Horticulture and Plant Sciences. "Biological and economic evaluation of maize-based cropping systems for Nigerian smallholders". THESIS_CSTE_HPS_Omokanye_A.xml, 2004. http://handle.uws.edu.au:8081/1959.7/797.

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Indigenous African shifting cultivation production systems, that were developed over many generations and took into account production potential as well as the constraints imposed by natural resources, are no longer practicable for Nigerian smallholder farmers. These systems relied on long fallow for fertility restoration after a period of cropping. Overpopulation has resulted in lower per capita land availability, necessitating a shift to sedentary cultivation systems. In such systems, fallow is short term (months) compared to shifting systems, where it lasted several years. This shift has resulted in overexploitation of land resources and despite intensification of agricultural production methods, non-sustainable demand on the natural resource base has increased and crop and animal production has declined. This study examined the performance of five maize-based cropping systems consisting of cereal-legume, cereal-cereal and cereal bare fallow rotations, to identify systems that have potential for increased agricultural production in the subhumid and mid-altitude zones of Nigeria. The study was conducted at Richmond, near Sydney, in NSW, Australia from 2000 to 2003. The trial investigated the effects of the combined use of legumes and N fertilizer in CSs to maintain or improve soil fertility, maize crop and maize storage silage production and yield and quality of all crop residues. This study showed that inclusion of a legume in the rotation is an important production and income generating strategy. Owing to their potential for increased maize productivity, to build up N-rich systems and to improve small holder levels of farm income, cropping systems with legumes should therefore be given more research attention in Nigeria
Doctor of Philosophy (PhD)
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Schelhas, John William Jr. "Socio-economic and biological aspects of land use adjacent to Braulio Carrillo National Park, Costa Rica". Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185452.

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Many national parks in lesser developed countries are threatened by adjacent human land uses. To meet both social and environmental needs, effective programs must be implemented to manage lands adjacent to national parks for conservation and development. This requires careful analysis of the socio-economic aspects of existing land use patterns and their implications for biological conservation. Research was undertaken adjacent to Braulio Carrillo National Park, Costa Rica. The biological integrity of the park depends on maintenance of natural habitats on lands adjacent to the lowland sector of the park. Existing lowland forest habitat adjacent to the park is rapidly being converted to pasture. Protecting the park's lowland biological resources depends on both stopping the influx of colonists into the area and encouraging land uses with biological conservation value outside the park. Both these issues are explored in detail. The rationale behind existing land uses in the region is discussed in relation to socio-economic variables identified from the literature on land use choice in Latin America. Large landholders generally engage in beef cattle ranching, frequently in association which land speculation. Small landholders prefer dairy cattle for cheese production is due to its low risk, stable markets, and the possibility of gradual and reversible entry. Smaller cattle operations use land more intensively, but by investing more labor appear to achieve sustainability. More intensive cash cropping is often combined with cattle to increase overall income. Timber production shows potential to partially replace cattle as an extensive, low risk land use. The impact of different adjacent land uses on park biological resources was assessed through a survey of biologists familiar with the region. The two land uses of greatest benefit to park resources were completely protected forest and natural forest management for timber production. The two land uses causing greatest harm to park resources were annual crops and pasture. Two management options for conservation and development adjacent to the park are proposed: (1) a forest buffer, and (2) a mosaic of different land uses, including pasture, perennial crops, and forest.
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Scarr, Lowell Martin. "Assessing the value of public investment into biological control research for invasive alien plants : the ARC PPRI Weeds Research Division". Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/d1020604.

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This study investigates the economic impact of the ARC PPRI Weeds Research Division. The Division researches appropriate methods of biological control for invasive alien plants (IAPs). These plants pose an increasing threat to environmental integrity and ecosystem service provision impacting on economic potential. Since the work of the Division is considered a public good, a predominantly descriptive approach has been adopted for the valuation process. A combination of quantitative cost analysis and a qualitative study of the impacts of research and invasive alien plants is used to deal with the challenges associated with non-market valuation. The study found that investment into the Weeds Division is a valuable activity that supports the long-term growth potential of the South African economy. The role of a well-functioning environment is highlighted as an essential base for the creation of sustained growth opportunities in any society. It was determined that investment into the Division should be increased into the future to support efficient spending of scarce state funds. Biological control research was found to provide strategic future growth potential, creating opportunities for the development of a competitive advantage in the biotechnology and environmental management sectors. The study adds to the increasing move towards a more holistic view of economic valuation, taking factors other than pure finance and econometrics into consideration. This is an important shift in prevailing economic thought, as a realisation is reached that a single, or even triple, bottom line is an outdated and insufficient decision making basis.
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Van, der Westhuizen Robert Rolfe. "A genetic analysis of biological and economic efficiency of post-weaning feedlot performance in beef cattle". Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50249.

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Thesis (PhD (Agric))--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: It is generally accepted that feed intake and growth (gain) are the most important economic components when calculating profitability in a growth test or feedlot. Feeding cost of animals is a major determinant of profitability in livestock production enterprises. Genetic selection to improve feed efficiency aims to reduce the cost of feeding in beef cattle production and thereby improve profitability. The objective of this study was to define a clear selection objective to enable South African beef breeders and especially the feedlot industry to select for post-weaning growth or feedlot performance and to identify factors influencing profitability in a feedlot environment. Because of the recording of individual feed intake and weight gain values in the South African Agricultural Research Councils' centralized growth tests, it was also possible to calculate a phenotypic value for feedlot profitability (R-value) for each bull tested in a centralized growth test. (Co)variances, using multitrait as well as random regression models, for and between feedlot profitability, weaning weight and other production, reproduction and efficiency traits were estimated. Residual feed intake (RFI) and feed conversion ratio (FCR) as efficiency traits were also compared to growth (average daily gain (ADG), weaning weight (WW) and shoulder height (SHD)), reproductive (scrotum circumference (SCR)) and profitability (feedlot profitability) traits measured in growth tests of young Bonsmara bulls. Consequently, a single post-weaning growth selection index value based on the economic and breeding values of different selection criteria related to feedlot profitability was composed. (Co)variance components, heritabilities and genetic correlations for and between initial weight (lW), final weight (FW), total feed intake (FI) and shoulder height (SHD) were estimated through the use of multitrait restricted maximum likelihood (REML) procedures. These breeding values (EBV s) were then used in a selection index to calculate a single economical value for each animal. This economical value is an indication of the gross profitability value or gross test value (GTV) of the animal in a post-weaning growth test. The heritability estimate of 0.36 for R-value, obtained from the multitrait analysis, shows that this trait is genetically inherited and that it can be selected for. The heritability for R-value obtained from the single trait random regression model varied between 0.57 and 0.62. The genetic correlations between the R-value and the other traits, obtained from the multitrait analysis, varied from negligible to high. The heritability estimated for FCR was 0.34 and for RFl 0.31 with a genetic correlation estimate of 0.75 between the traits. The estimated genetic correlation between profitability (R-value) and FCR and RFl were -0.92 and -0.59, respectively. The genetic correlation estimate of -0.92 between FCR and R-value is largely due to the part-whole relationship between these two traits. This is also shown in their genetic trends. The genetic correlations and expected correlated responses between RFl and FCR with R-value suggest that indirect selection for R-value through the direct selection for FCR and/or RFl will result in slower genetic progress in Rvalue than direct selection for R-value. However, where the R-value cannot be calculated and/or where direct selection for R-value is not possible, it would be better to select indirectly for R-value through the use of FCR rather than RF!. Consequently, a regression equation was developed (with an R2 of 0.82) to estimate a feed intake value for all performance-tested Bonsmara bulls which were group fed and whose feed intakes were unknown. These predicted feed intake values made it possible to calculate a feedlot or post-weaning growth profitability value (R-value) for all tested bulls even where individual feed intakes were unknown. Subsequently, an R-value for each bull was calculated in a favourable economic environment (FEE), an average economic environment (AEE) and in an unfavourable economic environment (VEE). The high Pearson and Spearman correlations between the EBV s based on AEE and the other two environments suggested that the average economic environment could be used to calculate EBVs for R-value or feedlot growth profitability. It is therefore not necessary to change the carcass, weaner or feed price on a regular basis to account for possible re-rankings based on R-value EBVs. Heritabilities for lW, FW, Fl and SHD were 0.41, 0.40, 0.33 and 0.51, respectively. The highest genetic correlations between these traits were the 0.78 (between lW and FW) and 0.70 (between Fl and FW). GTV values varied between -R192.l7 and R231.38, with an average of R9.31. The Pearson correlations between EBVs (for production and efficiency traits) and GTV range from -0.51 to 0.68. The lowest correlation (closest to zero) was 0.26 between the Kleiber ratio (KLB) and GTV. Correlations of 0.68 and -0.51 were estimated between average daily gain (ADG) and GTV and feed conversion ratio (FCR) and GTV, respectively. The heritabilities of the different traits included in the selection index suggest that it is possible to select for a GTV. The selection index can benefit feedlotting In selecting offspring of bulls with high GTV values to maximize profitability. The Pearson and Spearman correlations between the R-value EBVs and the index values (GTV) were very high (0.97). This high correlation of 97% indicates that it is not important which method is used to calculate a genetic post-weaning growth of feedlot profitability value. The selection index value is, however, more simplified than the feedlot profitability with less assumption. Therefore, it is recommended that the post-weaning selection index value be used as a selection objective in breeding programmes to improve post-weaning growth profitability rather than the more complex feedlot profitability value.
AFRIKAANSE OPSOMMING: 'N GENETIESE ANALIESE VAN DIE BIOLOGIESE EN EKONOMIESE DOELTREFFENTHEID VAN NASPEENSE GROEI IN VLEISBEESTE IN DIE VOERKRAAL: Dit word algemeen aanvaar dat voerinname en groei die twee ekonomies mees belangrike komponente in die berekening van 'n naspeense groei- of voerkraalwinsgewindheidswaarde is. Voerkostes is 'n bepalende faktor van winsgewindheid in enige lewendehawe boerderypraktyk. Seleksie om voerdoeltreffendheid te verbeter, verminder dus die voerkostes in vleisbeesproduksie en gevolglik 'n verhoging in die winsgewindheid. Die doelwit van die studie was om faktore te identifiseer wat 'n invloed op winsgewindheid in die voerkraaiomgewing het asook om 'n duidelike seleksiedoelwit te formuleer wat die Suid- Afrikaanse vleisbeesteiers en veral die voerkraalbedryf instaat sal kan stelom vir naspeense groeidoeltreffendheid ofvoerkraalwinsgewindheid te selekteer. As gevolg van die aantekening en rekordhouding van weeklikse individuele voennnames en gewigstoenames van alle prestasiegetoetsde bulle, in 'n gesentraliseerde groeitoets deur die Suid- Afrikaanse Landbou Navorsingsraad getoets, was dit moontlik om vir elk van hierdie bulle 'n fenotipiese voerkraalwinsgewindheidswaarde (R-waarde) te kon bereken. (Ko)variansies is vir en tussen voerkraalwinsgewindheid, speengewig en ander produksie-, reproduksie- en doeltreffendheidseienskappe bereken deur van meereienskap en ewekansige regressie modelle gebruik te maak. Twee doeltreffendheidseienskappe naamlik residuele voerinname (RFI) en voeromsetverhouding (FCR) is ook met groei (gemiddelde daaglikse toename (ADG), speengewig (WW) en skouerhoogte (SHD)), reproduksie (skrotumomvang (SCR)) en winsgewindheidseienskappe (voerkraalwinsgewindheid (R-waarde)) vergelyk, om sodoende te bepaal watter een die mees geskikte eienskap is om indirek vir voerkraalwinsgewindheid of groei, gebaseer op teeltwaardes en ekonomiese waardes vir die verskillende eienskappe, wat 'n invloed op naspeense groei winsgewindheid het, gestruktueer. (Ko)variansiekomponente, oorerflikhede en genetiese korrelasies vir en tussen begingewig (lW), eindgewig (FW), voerinname (FI) en skouerhoogte (SHD) is bereken deur van 'n meereienskap (REML) ontleding gebruik te maak. Hierdie teelwaardes (EBVs) is vervolgens in 'n seleksie-indeks gebruik om 'n enkele ekonomies of voerkraal-winsgewindheids seleksie-indekswaarde (GTV) vir elke dier te bereken. Hierdie ekonomiese waarde is 'n aanduiding van die bruto winsgewindheidswaarde ofbruto toetswaarde (GTV) van die dier in 'n naspeentoets. Die oorerflikheid, vanuit die meereienskapontleding vir R-waarde beraam, was 0.36. Hierdie oorerflikheid dui daarop dat die eienskap oorerflik is en dat dit wel moontlik is om daarvoor te selekteer. Die ooreflikhede van R-waarde, voorspel vanuit die enkeleienskap ewekansige regressieontleding varieer tussen 0.57 en 0.62. Die genetiese korrelasie tussen R-waarde en ander eienskappe, vanuit die meereienskap ontleding beraam, varieer tussen weglaatbaar klein tot hoog. Die oorerflikheid van FeR was 0.34 en van RFI 0.31 met 'n genetiese korrelasie van 0.75 tussen die twee eienskappe. Die genetiese korrelasie tussen R-waarde en FeR, en R-waarde en RFI was onderskeidelik -0.92 en -0.59. Die rede vir die hoë negatiewe genetiese korrelasie tussen R-waarde en FeR van -0.92 is omdat dieselfde komponente in die berekening van die twee eienskappe gebruik is. Dit word ook in die genetiese tendense weerspeël. Die genetiese korrelasies en verwagte gekorreleerde responsies tussen R-waarde en FeR, en tussen R-waarde en RFI dui daarop dat stadiger genetiese vordering verkry sal word in R-waarde deur direkte seleksie vir beide FeR en RFI as wat verkry sal word deur die direkte seleksie vir R-waarde. Wanneer 'n R-waarde egter nie bereken kan word nie of waar dit nie moontlik is om direk vir R-waarde te selekteer nie, sal vinniger genetiese vordering in R-waarde gemaak word deur die direkte seleksie vir FeR as vir RF!. 'n Regressievergelyking is geformuleer (met 'n R2 van 0.82) om vir alle prestasiegetoetsde bulle, waar bulle in 'n groep gevoer is en individuele voerinnames onbekend is, 'n voerinnamewaarde te voorspel. Hierdie voorspelde voerinnames maak dit moontlik om vir elke prestasiegetoetsde bul ,'n naspeengroei- of voerkraalwinswaarde (R-waarde) te bereken, al is hulle individuele voerinnames onbekend. Vervolgens is drie verskillende R-waarde vir vleisproduksie vir elke bul bereken naamlik, in 'n gunstige ekonomiese omgewing (FEE), 'n gemiddelde ekonomiese omgewing (AEE) en 'n ongunstige ekonomiese omgewing (VEE). Die hoë Pearson en Spearman korrelasies tussen die EBVs vir R-waarde, bereken in die AEE en die EBVs in die ander twee ekonomiese omgewings, dui daarop dat die AEE gebruik kan word om EBVs vir naspeense groeiof voerkraalwins te bereken. Dit is dus nie nodig om op 'n gereelde grondslag die karkasprys, lewendige speenkalfprys of die voerprys te verander nie. Oorerflikhede, vanuit die meereienskap ontledings VIr lW, FW, FI en SHD verkry, was onderskeidelik 0.41, 0.40, 0.33 en 0.51. Die hoogste genetiese korrelasies tussen die eienskappe was 0.78 tussen lW en FW en 0.70 tussen FI en FW. GTV indekswaardes varieer tussen -Rl92.17 en R231.38 met 'n gemiddelde waarde van R9.31. Die Pearson korrelasies tussen die EBVs van produksie- en doeltreffenheidseienskappe en GTV het tussen -0.51 en 0.68 gevarieer. Die korrelasie naaste aan zero, van 0.26, was die korrelasie tussen GTV en die Kleiber-verhouding. Die korrelasies tussen GTV en ADG, en GTV en FeR was onderskeidelik 0.68 en -0.51. Die oorerflikhede van die verskillende eienskappe wat in die seleksie-indeks ingesluit is, dui daarop dat die indekswaarde weloorerflik is en dat seleksie hiervoor wel moontlik is. Hierdie indekswaarde kan deur die voerkraaiindustrie gebruik word om nageslag van diere met hoë GTV waardes te selekteer om sodoende maksimum wins uit die voerkraai te genereer. Die Pearson en Spearman korrelasies tussen R-waarde EBVs en die indekswaardes (GTV) was besonder hoog (0.97). Hierdie hoë korrelasie dui daarop dat dit geen verskil sal maak watter een van die twee metodes gebruik word in die berekeninge van 'n naspeense groei- of voerkraalwinswaarde nie. Die seleksie-indeks metode is egter minder gekompliseerd met minder aannames as in die geval van die rekeningkundige fenotipiese benadering (R-waarde). As gevolg hiervan, word die naspeense seleksie-indeks waardes (GTV) aanbeveel om te gebruik as 'n teeldoelwit in telingsprogramme om naspeense groei- of voerkraaiwins geneties te verbeter, eerder as die meer gekompliseerde fenotipiese voerkraaiwins (R-waardes) metode.
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Gaika, Lindiwe. "Adequacy of existing protected areas in conserving biodiversity at global and regional levels in relation to socio-economic conditions". Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9646_1254305009.

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At a meeting of worl leaders at the United Nations Conference on Environment and Development in Rio de Janeiro in 1992, it was recognized that because of the tremendous increase in the size of the global populations (which now is estimated to exceed six billion), there were concerns that global biodiversity was at risk if insufficient land were not put aside for conservation within formal Protected Areas. The primary aim of this study was to compare investment in Protected Areas in relation to socio-economic conditions at global and regional levels.

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Olstorpe, Matilda. "Feed grain improvement through biopreservation and bioprocessing : microbial diversity, energy conservation and animal nutrition aspects /". Uppsala : Dept. of Microbiology, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200877.pdf.

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Law, Matthew Charles. "Willingness to pay for the control of water hyacinth in an urban environment of South Africa". Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1002731.

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Water hyacinth is recognised as one of the most problematic invasive aquatic plant species in Africa. For this reason considerable funds are spent each year on itscontrol. As a consequence of the amount of money being spent on problems such as the invasion of water hyacinth, and because of the recognition of the ongoing and accelerated efforts that are required in the future, recent research has focused on accurately quantifying the costs and benefits of control of invasive species to aid policy decisions.A comprehensive cost-benefit analysis would be able to identify if the funds are justified and are being spent effectively. This thesis provides an example of a cost-benefit analysis of funds spent on the control of water hyacinth in an urban environment in South Africa. In order to develop a comprehensive assessment of the total economic value of the control of water hyacinth to an urban population, the Nahoon River in East London was selected as the study site to calculate the benefits of control. In addition to valuing the direct services provided by the resources that are traded in the market (in this case water provision), a contingent valuation study was undertaken in Abbottsford and Dorchester Heights (two suburbs in East London banking the Nahoon River). These were done in order to assess any non-use value a sample of 132 households of the population has for the control of water hyacinth, and any use values that are not traded in the market, for example recreational value. When the benefits of control of water hyacinth were compared to the costs of one of the least cost effective methods of control (herbicidal control), the benefits outweighed the costs by a ratio of more than 4:1, and for the most cost effective method of control the ratio was almost 6:1. These results provide a justification for the funds that are devoted to the control of water hyacinth, providing an argument for the continued expenditure for its control, and for further research into more cost effective methods of control, such as biological control.
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Dhanasekaran, Vijaykrishna. "Freshwater fungi biodiversity, origins and molecular taxonomy /". Thesis, Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B32017583.

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Li, Yan Ting. "Seeking the balance between trade liberalization and cultural diversity in the framework of WTO and UNESCO :some suggestions to China". Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2580115.

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Nqobizitha, Dube. "Economic evaluation of possible loss of Prosopis pods as a result of biological control in the Northern Cape Province, South Africa". Thesis, University of Fort Hare, 2009. http://hdl.handle.net/10353/394.

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Species of Prosopis (Mimosaceae), or mesquite, are native to the Americas and introduced in South Africa as agro forestry trees to provide wood, fodder and shade in the late 1800s. In the Northern Cape Province, these trees have been particularly used for their pods by local farmers and local industry. However due to Prosopis’ ability to spread rapidly there has been increasing pressure to step up control of the tree. Due to the costs associated with most control methods biological control has been singled out as the most viable control method worth pursuing. This thesis attempts to explain and shed light on the effects that increased biological control of Prosopis would have on the farming community and Prosopis based businesses in the area. Two hypothetical scenarios were used, the first being a possible 50% reduction in available pods and the other a possible 100% reduction. In an effort to explain these effects data was collected from a series of collection activities in the form of a pilot study and two unique questionnaire surveys. Twenty-seven farmers and one Prosopis based business were interviewed at random with the data analysed and documented. Results showed that the business community is the main user of pods incurring crippling losses in the event of a 50% or 100% decrease in available pods. Using control costs from working for water De Aar long term costs of the presence of Prosopis were estimated and compared to the estimated provincial cost of losing pods giving a cost comparison ratio of (α)270 million : Y(N(15.7million)). Only 48% of the respondents valued pods and 11% had traded in pods, the top concern resulting from the invasion was the loss of underground water. With a 50% decline in available pods, all respondents indicated unchanged effects. However empirical results showed that with a 100% decline in pods estimate losses of R 5 818 per farm are expected. The cost comparison ratio showing the losses farmers bore with Prosopis in the area and the losses they would suffer with a 100% decline in pods was R11 389 + (K): R5 818. In light of the empirical results, policy recommendations that support the introduction of more effective biological control agents have been made with areas for further research identified and discussed.
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Zazini, Novela. "The impact of diversity in reporting on the editorial independence of small-scale regional community newspapers based in the Eastern Cape". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53123.

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Thesis (MPhil)--University of Stellenbosch, 2003
ENGLISH ABSTRACT: Journalism in South Africa has to be looked at in its historical context. South Africa was a country characterised by disparities. The same can be said about the media in this country. Mainstream media concentrated on the priviledged few and projected their views. On the other hand small regional community media aimed at marginalized communities provided a "voice for the voiceless." These small newspapers focused on the disadvantaged, rural and semi-literate communities. As a result of the history of this country, mainstream media neglected the marginalized communities. A need arose for redressing that imbalance and diversifying reporting. Small community newspapers were the means to achieve that. Unfortunately these newspapers fail to attract advertisers for various reasons. A large percentage of the marginalized communities were unemployed and very few could afford to buy newspapers. One copy of a newspaper was shared by between eight (8) and ten (10) people and that meant low circulation figures. The level of literacy was low and those who were literate, had to read to those who could not. The advertising industry was and is still biased and prejudiced against community media. Most small community newspapers died because of these economic factors. This brings about a need for funding of these newspapers. Are funders prepared to pump money without interfering with editorial independence of newspapers? This Assignment sets out to analyse the conflict between the necessity for diversity in reporting (accommodating the previously neglected) and journalistic independence (related to the need for funding). For the purposes of this Assignment, the focus will be on small regional community newspapers in the Eastern Cape, the Border/Kei- area in particular. The purpose of this Assignment is firstly to ascertain whether moves to diversify media/reporting are taking place - an ethical concern. Secondly to establish whether those who fund these newspapers interfere with their content. Various methods of research are used to establish the purpose of the Assignment. Research methodology in use reveals that attempts to diversify the media by focusing on marginalized communities becomes futile. The reason being that those who provide funding directly or indirectly impose their ideas on the newspapers. Small community newspaper then project the ideas of the priviledged people as result of the pressure from funding. It can be concluded that a solution that regards diversity in reporting and editorial independence as ethical principles is necessary (deontological model). That same solution would have to provide consequences that benefit the greatest number of people (utilitarian approach). Such a solution would in essence ensure the survival and sustainability of small regional newspapers and their editorial independence.
AFRIKAANSE OPSOMMING: Joernalistiek in Suid-Afrika moet binne die historiese konteks beskou word. Die land was gekenmerk deur ongelykhede. Dieselfde norm geld vir die media. Die hoofstroom media wat op die kleiner, bevoorregte groep gekonsentreer het, het uiteraard slegs hul siening geprojekteer. Andersyds is die kantlyn "stom" gemeenskappe tog voorsien van 'n stem deur die klein, gemeenskapsgerigte media. Dié klein koerante het gefokus op semi-geletterde, minder bevoorregte inwoners van die landelike gebiede. Dit was juis hierdie kantlyn gemeenskappe wat om historiese redes verwaarloos was. Die behoefte het dus ontstaan vir die regstelling van die wanbalans en 'n diversifisering van verslaggewing. Kleiner gemeenskapskoerante sou ideaal geskik wees om hierdie doel te bereik. Ongelukkidg misluk hulle om verskeie redes om adverteerders te lok. Die hoë werkloosheidssyfer en gepaardgaande armoede in hiedie kantlyngemeenskappe het koerante onbekostigbaar gemaak vir die meerderheid. Een kopie is deur 8-10 mense gedeel. Dit het op sy beurt die sirkulasiesyfer laat daal. Dié wat kon lees, moes voorlees aan die meerderheid ongeletterdes. Die advertensiewese was en is steeds bevoordeeld teen die klein gemeenskapsmedia. Gevolglik kon hierdie projekte in die verlede om verskeie ekonomiese redes nie oorleef nie. Dit op sy beurt plaas die behoefte vir befondsing onder die soeklig. Die vraag ontstaan nou of sodanige befondsers die redaksionele onafhanklikheid van hierdie media sal respekteer? Hierdie tesis poog om 'n analise te maak van die konflik wat onstaan wanneer aan die een kant gepoog word om alle kantlyn groepe te betrek deur diversifisering en aan die ander kant die befondsing wat bekom moet word sonder om joernalistieke onafhanklikheid prys te gee. Vir die doel van hierdie tesis sal die fokus wees op die klein gemeenskapskoerante in die Oos-Kaap, meer spesifiek die Grens/Keigebied. Die primêre doel van die tesis is, eerstens om vas te stelof daar enige diversifisering plaasvind in die joernalistieke/media area - dit is 'n etiese kwessie. In die tweede plek moet vasgestel word of die befondsers inmeng in die inhoud van die ontvangerkoerante. Verskeie vorms van navorsing word gebruik om bogenoemde doelwite te bereik. Navorsingsmetodiek het bewys dat huidige pogings om te diversifiseer sodat kantlyngemeenskappe betrek kan word, misluk. Die rede hiervoor is dat die befondsers - direk of indirek - hul idees, wat uiteraard die bevoorregte gemeenskap weerspieël, afdwing. Die slotsom is dat enige oplossing gebaseer moet wees op beginsels/reëls wat die meerderheid sal bevoordeel. So 'n oplossing sal aanpasbaar moet wees by omstandighede. Dit moet egter ten alle tye die oorlewing en volhoubaarheid van die klein gemeenskapskoerante en hul redaksionele onafhanklikheid, waarborg.
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Prinsloo, Shireen. "The distribution and diversity of macroalgae in selected estuaries along the Eastern Cape coast of South Africa". Thesis, Nelson Mandela Metropolitan University, 2012. http://hdl.handle.net/10948/d1012314.

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The growth and accumulation of macroalgae in estuaries are a common sight throughout the world (Boyer and Fong, 2005). Because macroalgae establish such complex but important links with other components within an estuary, it is essential to know which variables control and regulate their occurrences. The type of algae that will occur in an estuary depends however, on the physical and chemical features of the particular estuary (Lobban and Harrison, 1994). The focus of this study was to document and provide a listing of algae from estuaries around the Eastern Cape coast of South Africa and describe the communities which form within each estuarine habitat. The questions posed were: Do algae assemblages differ in estuaries with different environmental conditions? Are different plant communities inhabited by different algae communities? Also, are algae diverse in estuaries that are in a pristine condition? The estuaries were Mngazana, Ngqusi/Nxaxo, Mtati, Mpekweni, East Kleinemonde, West Kleinemonde, Kariega, Bushmans, Kowie and the Sundays estuary. Percentage cover surveys were conducted and environmental parameters recorded to determine community structure of algae and their environmental tolerances. A total of 49 different macroalgal species were identified from 11 estuaries, which were dominated by Chlorophytes (23 species) and Rhodophytes (17 species). The Ochrophytes consisted of 10 species. The highest number of species recorded was 29 at the Bushmans estuary (March 2009), while the lowest number (4 species) was recorded at Mtati (October 2008). Common Chlorophytes found included Ulva prolifera, Chaetomorpha linum and Codium tenue. In the Division Ochrophyta, species from the Genus Ectocarpus were the most common. Of the red algae filamentous reds, Polysiphonia incompta and Polysiphonia kowiensis were the common algae found at estuaries. Salinity (p= 0.029861; n= 49) and temperature (p= 0.037641; n= 49) were the driving environmental parameters of estuaries and significantly influenced richness of species. In ordination analyses, patterns of biogeographic distribution were noticeable and were described by salinity. Four gradients caused by salinity were therefore found – which is inversely correlated to water clarity. Moreover, a clear split between temporarily open/closed and the permanently open estuaries was observed. Samples grouped into four communities presumably based on the similarity in conditions of estuaries. Within each estuarine community and major type of estuary there was a range of environmental conditions. However, the macroalgae within each community may not have been colonists of or found in greatest abundances in the estuaries of these communities per se, but may have grouped together in this manner based on the optimum growing conditions for them. Also, specific algal groups were not directly determined by the type of estuary they were found in; they were driven by environmental ranges rather. The results therefore support hypothesis one which states species distribution and diversity differ and are influenced by environmental gradients of the estuary. Although close species and habitat relationships were apparent from the ordination analyses, providing support for hypothesis two which states “Different plant communities in estuaries will be inhabited by different macroalgae communities”, the evidence was not substantial enough to provide sufficient support for the hypothesis. Lastly, the hypothesis “Macroalgae are diverse in estuaries that are in a pristine condition” was not accepted as highest species numbers were found in estuaries of greatest anthropogenic disturbance (e.g. Bushmans estuary) and not in estuaries which where ecologically more natural (e.g. Mtati estuary). By doing monthly macroalgal sampling over a period of one year for example one would obtain greater information of biodiversity, and patterns of macroalgal seasonality may be uncovered as well. This is an area of reasearch which needs to be investigated in the future as it would greatly add to the understanding of the role macroalge have in an estuarine environment.
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Moore, Bronwyn Ann. "Investigation into the technical feasibility of biological treatment of precious metal refining wastewater". Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1002013.

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The hydrometallurgical refining of platinum group metals results in large volumes of liquid waste that requires suitable treatment before any disposal can be contemplated. The wastewater streams are characterized by extremes of pH, high inorganic ion content (such as chloride), significant residual metal loads and small amounts of entrained organic compounds. Historically these effluents were housed in evaporation reservoirs, however lack of space and growing water demands have led Anglo Platinum to consider treatment of these effluents. The aim of this study was to investigate whether biological wastewater treatment could produce water suitable for onsite reuse. Bench-scale activated sludge and anaerobic digestion for co-treatment of an acidic refinery waste stream with domestic wastewater were used to give preliminary data. Activated sludge showed better water treatment at lab scale in terms of removal efficiencies of ammonia (approximately 25%, cf. 20% in anaerobic digestion) and COD (70% cf. 43% in digestion) and greater robustness when biomass health was compared. Activated sludge was consequently selected for a pilot plant trial. The pilot plant was operated on-site and performed comparably with the bench-scale system, however challenges in the clarifier design led to losses of biomass and poor effluent quality (suspended solids washout). The pilot plant was unable to alter the pH of the feed, but a two week maturation period resulted in the pH increasing from 5.3 to 7.0. Tests on algal treatment as an alternative or follow-on unit operation to activated sludge showed it not to be a viable process. The activated sludge effluent was assessed for onsite reuse in flotation and it was found that there was no significant difference between its flotation performance and that of the process water currently used, indicating the effluent generated by the biological treatment system can be used successfully for flotation. Flotation is the method whereby minerals refining operations recover minerals of interest from ore through the addition of chemicals and aeration of the ore slurry. Target minerals adhere to the bubbles and can be removed from the process.
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Dutra, Paula Hebling. "Institution Interaction and Regime Purpose - Considerations Based on TRIPS/CBD". Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1180729582.

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Kehinde, Temitope Olatayo. "Effects of vineyard management and landscape context on taxonomic diversity and interaction networks of flower-visiting insects in the Cape Floristic Region biodiversity hotspot". Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17980.

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Thesis (PhD)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: Both taxonomic diversity and diversity of species interaction networks are experiencing declines as a result of agricultural intensification at habitat and landscape scales. Reversing this trend is a key conservation issue, particularly for important functional groups such as flower-visiting insects and the networks within which they interact. This is of great concern in regions of high conservation priority such as the Cape Floristic Region (CFR), known for its high level of floral and faunal endemism and exceptional species turnover. Holistic approach to conservation in agricultural landscapes involves both preservation of natural land and wildlife friendly management of the farm land to achieve conservation targets. The value of these extensive management approaches is yet to be fully assessed, especially in perennial systems such as vineyards. I examined here the effects of vineyard management and landscape context on species richness and abundance of flower-visiting insects and their species interaction networks. Possible taxon specific effects were verified. I also investigated whether vineyards under organic and conventional management homogenized insect-flower interaction networks and whether vineyards with different management practices vary in patterns of species turnover. I sampled flower-visiting insects and their interactions in organic and conventional vineyards, and in natural reference sites. Inclusion of natural reference sites enabled me to make management recommendations for patches of natural vegetation in CFR agricultural landscape. Statistical models showed taxon-specific benefit of organic farm management, and of landscape (distance to natural habitat). There was benefit to monkey beetles (Scarabaeidae) but not to bees (Apidae). Organic vineyards had a higher number of insect-flower interactions than conventional ones, but vineyards under the two types of management were similar in terms of other important network indices. However, networks of the vineyards were more nested than the natural sites, indicating that they may be potentially more stable to perturbation and random extinctions. Multivariate dispersion tests revealed insect-flower interaction networks were not homogenized by both organic and conventional vineyards across the landscapes. I also found, through additive partitioning, that organic and conventional vineyards were similar in terms of species turnover of bees and flowering plants. The findings of this study provide heuristic value to current debates on the value of vineyard habitats for insect conservation. Both organic and conventional vineyards that promote sustainable management of the non-crop floral vegetation between vineyard rows are potential solutions for conservation of flower-visiting insects and their interactions. Also, attention has to be paid to the quality and connectivity of the natural habitat patches that are within CFR agricultural landscape. Site specific management and assessment of the value of these landscape elements is important. Management approaches such as carefully controlled burning may be beneficial, as the CFR natural vegetation is a fire-driven community.
AFRIKAANSE OPSOMMING: Taksonomiese diversiteit en diversiteit van spesies-interaksie netwerke ondervind beide afnames as gevolg van landboukundige intensifikasie op habitat en landskap skaal. Om die neiging terug te swaai, is ’n sleutel bewaringsaangeleentheid, veral vir belangrike funksionele groepe soos blom-besoekende insekte en die netwerke waarbinne hulle op mekaar inwerk. Dit is van groot kommer in streke met hoë bewaringsprioriteite soos in die Kaapse Floristiese Streek (KFS), bekend vir sy hoë vlak van plant- en dierendemisme en buitengewone spesies kentering. ’n Holistiese benadering tot bewaring van landboukundige landskappe behels beide die bewaring van natuurlike land en natuurlewe-vriendelike bestuur van die plaasgrond om bewaringsdoelwitte te bereik. Die waarde van hierdie ekstensiewe bestuursbenaderings moet nog volledig bepaal word, veral in meerjarige sisteme soos wingerde. Ek het die uitwerkings van wingerdbestuur en landskapsamehang op spesiesrykheid en volopheid van blombesoekende insekte en hulle spesies interaksie netwerke ondersoek. Moontlike takson-spesifieke uitwerkings is nagegaan. Ek het ook ondersoek ingestel of wingerde onder organiese en gebruiklike bestuur ooreenstemmende insek-blom interaksie netwerke met wingerde met verskillende bestuurspraktyke in patroon van spesies kentering gewissel het. Ek het blom-besoekende insekte en hulle interaksies in organiese en konvensionele wingerde, asook in natuurlike verwysingsgebiede gemonster. Insluiting van natuurlike verwysingsgebiede het my in staat gestel om bestuursvoorstelle vir gebiede van natuurlike plantegroei in KFS landboulandskappe voor te stel. Statistiese modelle toon takson-spesifieke voordeel van organiese plaasbestuur en van die landskap (afstand van natuurlike habitat) self. Daar was voordeel vir bobbejaankewers (Scarabaeidae), maar nie vir bye (Apidae) nie. Organiese wingerde het ’n groter getal insek-blom interaksies as konvensionele wingerde gehad, maar wingerde onder beide tipes van bestuur was soortgelyk in terme van ander belangrike netwerk aanduiders. Netwerke van wingerde was egter meer geklomp dan natuurlike gebiede wat aandui dat hulle potensieel meer stabiel betreffende versteuring en lukrake uitsterwings is. Multivariate verspreidingstoetse het aangetoon dat insek-blom interaksie netwerke by beide organiese en konvensionele wingerde oor landskappe nie eenvormig was nie. Ek het ook bevind deur aanvullende verdeling dat organiese en konvensionele wingerde gelykwaardig was in terme van spesies kentering van bye en blomplante. Die bevindings van hierdie studie verskaf heuristise waarde tot huidige debatte oor die waarde van wingerdhabitatte vir insekbewaring. Beide organies en konvensionele wingerde wat volhoubare bestuur van die nie-gewas plantegroei binne wingerdrye bevorder, is moontlike oplossings vir die bewaring van blom-besoekende insekte en hulle wisselwerkings. Bykomend moet aandag gegee word aan die kwaliteit en verbindings van en tussen natuurlike habitat gebiede binne die KFS landboulandskap. Plekspesifieke (plaaslike) bestuur en bepaling van die waarde van hierdie landskapelemente is belangrik. Bestuursbenaderings, soos noukeurig beheerde brand, mag voordelig wees aangesien die KFS natuurlike plantegroei ’n vuurgedrewe gemeenskap is.
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Gumede, Halalisani. "The development of a putative microbial product for use in crop production". Thesis, Rhodes University, 2008. http://eprints.ru.ac.za/1352/.

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Jern, Isacsson Gretha, i Robin Emilie Elfsberg. "Rösterna bakom den blågröna vågen och jordbruksrevolutionen - Alternativ livsmedelsproduktion i prat och praktik". Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-22319.

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Sveriges livsmedelssystem står inför stora utmaningar såsom negativ miljöpåverkan och beroendet av att importera både livsmedel och insatsvaror. Livsmedelsproduktionen, som idag domineras av det konventionella jordbruket, har bland annat inneburit utarmade jordar och exploaterade resurser samt utsläpp av gifter. Studien syftar till att sammanställa och jämföra den vetenskapliga forskningen och samhällsdebatten angående alternativ livsmedels-produktion. Studien är avgränsad till att redogöra för produktionssystemen regenerativa jordbruk och akvaponiska system. Den vetenskapliga forskningen angående regenerativa jordbruk och akvaponiska system sammanställdes i ett kunskapsläge. En kvalitativ innehållsanalys utfördes för att identifiera och sammanställa samhällsdebatten kring systemen. Samhällsdebatten rörande de två alternativa livsmedelsproduktionssystemen bildade följande teman: den samordnande rösten, den offentliga rösten, forskarens röst, den operativa rösten, samt den övriga rösten. Inom dessa teman identifierades följande sex kodord: livsmedelsförsörjning, miljömässiga aspekter, ekonomiska aspekter, sociala aspekter, utmaningar samt möjligheter. I vår undersökning har vi inte formulerat några nya begrepp, däremot har vi funnit samband såväl som avvikelser och glapp mellan samhällsdebatten och den vetenskapliga forskningen.
Sweden's food system faces major challenges such as negative environmental impact and is dependent on importing both food and intermediate goods. Food production, which today is dominated by conventional agriculture, has meant, among other things, depleted soils and exploited resources as well as emissions of toxins. This study aims to compile and compare the scientific research and the public debate regarding alternative food production systems. The study is limited to account for the production systems regenerative agriculture and aquaponic systems. The scientific research regarding regenerative agriculture and aquaponic systems was compiled in a state of knowledge. A qualitative content analysis was performed to identify and compile the public debate about the systems. The public debate concerning alternative food production systems formed the following themes: the coordinating voice, the public voice, the researcher's voice, the operational voice, and the miscellaneous voice. Within these themes, the following six code words were identified: food supply, environmental aspects, economic aspects, social aspects, challenges and opportunities. In our study, we have not formulated any new concepts, however, we have found connections as well as discrepancies and gaps between the public debate and the scientific research.
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Tacconi, Luca Economics &amp Management Australian Defence Force Academy UNSW. "The process of forest conservation in Vanuatu : a study in ecological economics". Awarded by:University of New South Wales - Australian Defence Force Academy. School of Economics and Management, 1995. http://handle.unsw.edu.au/1959.4/38725.

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The objective of this thesis is to develop an ecological economic framework for the assessment and establishment of protected areas (PAs) that are aimed at conserving forests and biodiversity. The framework is intended to be both rigorous and relevant to the decision-making process. Constructivism is adopted as the paradigm guiding the research process of the thesis, after firstly examining also positivist philosophy and ???post-normal??? scientific methodology. The tenets of both ecological and environmental economics are then discussed. An expanded model of human behaviour, which includes facets derived from institutional economics and socioeconomics as well as aspects of neoclassical economics, is outlined. The framework is further developed by considering, from a contractarian view point, the implications of intergenerational equity for biodiversity conservation policies. The issues of intragenerational distribution and allocation are then considered. In this regard, cost-benefit analysis (CBA), as applied to the valuation of forests, PAs, and biodiversity, is critically reviewed. A participatory approach to decision-making, which may also include CBA, is then proposed. The resulting ecological economic framework may be thus summarised: (a) ecosystem use patterns should be chosen on the basis of their sustainability, distributional, and efficiency aspects; (b) systems of PAs should be established in order to achieve minimal intergenerational equity; (c) intragenerational equity requires the correction of the asymmetrical distribution of the costs and benefits arising from the establishment of PAs; (d) the institutional features relevant to the environmental-economic issues being analysed should be considered; and (e) the decision-making process should be participatory and action oriented. The framework is applied to two case studies in Vanuatu. These applications detail (a) stakeholders??? views and trade-offs faced in relation to forest management (b) modes of participatory research and decision-making, (c) forms of compensation that may be adopted in correcting asymmetrical distributions of the costs and benefits of PAs, and (d) institutional influences on ecosystems use and implications for conservation projects. The institutional arrangements developed for the establishment of the PAs are presented. The application of this ecological economic framework has resulted in the formal establishment of one PA and the identification and assessment of five other PAs.
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Mason, Nicholas Craig. "Forging a New Global Commons Introducing common property into the global genetic resource debate". Thesis, University of Canterbury. School of Political Science and Communication, 2004. http://hdl.handle.net/10092/904.

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This thesis provides an analysis of recent attempts to regulate the governance of genetic resources through the initiation of new global commons regimes. These attempts have arisen out of a combination of the growing recognition of genetic resources' value and global nature; a new resurgence in support for the common property paradigm; and, during a period in which the world is becoming increasingly globalised, with many governance competencies moving to the supranational level. They can be viewed as part of a broader effort to proffer the common property approach as a legitimate alternative in the property regime debate: a debate that has increasingly become trapped in the public-private dichotomy at the dawn of the twenty-first century. The aim of this thesis is to investigate the success of these attempts, and offer suggestions about how future attempts might be more successful. While there are a multitude of books, articles, opinion pieces and media reports produced that concern themselves with property theory, intellectual property theory, the efficacy or morality of applying property regimes to living materials, and the threats and promises of globalisation, all of which influence the notion of a potential global genetic commons, relatively little has been written directly on the idea of applying global common property regimes to genetic resource governance issues. The first part of this thesis constructs a theory of a global genetic commons, drawing inspiration from a variety of sources, while the second part tests this theory in order to analyse the outcomes of the recent attempts, and suggest directions for future research. The thesis finds that the conception of a global genetic commons is indeed a valid one, and that while not all attempts so far have been successful, the common property paradigm does offer valuable insights for the future governance of genetic resources at the global level.
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Glenk, Klaus. "Economic Valuation of Biological Diversity". Doctoral thesis, 2006. http://hdl.handle.net/11858/00-1735-0000-0006-AEC2-0.

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Litvin, Oren. "Heterogeneity and Context-Specificity in Biological Systems". Thesis, 2014. https://doi.org/10.7916/D84T6GHB.

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High throughput technologies and statistical analyses have transformed the way biological research is performed. These technologies accomplish tasks that were labeled as science fiction only 20 years ago - identifying millions of genetic variations in a genome, a chip that measures expression levels of all genes, quantifying the concentration of dozens of proteins at a single cell resolution. High-throughput genome-wide approaches allowed us, for the first time, to perform unbiased research that doesn't depend on existing knowledge. Thanks to these new technologies, we now have a much better understanding on what goes awry in cancer, what are the genetic predispositions for numerous diseases, and how to select the best available treatment for each patient based on his/her genetic and genomic features. The emergence of new technologies, however, also introduced many new problems that need to be addressed in order to fully exploit the information within the data. Tasks start with data normalization and artifact identification, continue with how to properly model the data using statistical tools, and end with the suitable ways to translate those statistical results into informative and correct biological insights. A new field - computational biology - was emerged to address those problems and bridge the gap between statistics and biology. Here I present 3 studies on computational modeling of heterogeneity and context-specificity in biological systems. My work focused on the identification of genomic features that can predict or explain a phenotype. In my studies of both yeast and cancer, I found vast heterogeneity between individuals that hampers the prediction power of many statistical models. I developed novel computational models that account for the heterogeneity and discovered that, in most cases, the relationship between the genomic feature and the phenotype is context-specific - genomic features explain, predict or exert influence on the phenotype in only a subset of cases. In the first project I studied the landscape of genetic interactions in yeast using gene expression data. I found that roughly 80% of interactions are context-specific, where genetic mutations influence expression levels only in the context of other mutations. In the second project I used gene expression and copy number data to identify drivers of oncogenesis. By using gene expression as a phenotype, and by accounting for context-specificity, I identified two novel copy number drivers that were validated experimentally. In the third project I studied the transcriptional and phenotypic effects of MAPK pathway inhibition in melanoma. I show that most MAPK targets are context-specific - under the control of the pathway only in a subset of cell lines. A computational model I designed to detect context-specific interactions of the MAPK pathway identified the interferon pathway as a major player in the cytotoxic response of MAPK inhibition. Taken together, my research demonstrates the importance of context-specificity in the analysis of biological systems. Context-specific computational modeling, combined with high-throughput technologies, is a powerful tool for dissecting biological networks.
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26

Oguamanam, Chidi Vitus. "Biological diversity and intellectual property rights : the challenge of traditional knowledge". Thesis, 2000. http://hdl.handle.net/2429/10735.

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The abundance of wealth and technology in the North, and biological diversity and poverty in the South provokes an inquiry into an appropriate modality for the equitable harnessing and allocation of biodiversity dividends. Over the years, the traditional knowledge relating to biological diversity has been regarded as part of the "global intellectual commons", open to exploitation by all, and subject to validation by formal methods. That knowledge has remained the source of both increasing knowledge and critical discoveries of the therapeutic values of most components of biological diversity. There is a consensus between the North and the South that an effective biodiversity conservation strategy should be one capable of providing incentives to the traditional custodians of wild habitat. Intellectual property is generally recognised as an appropriate framework to implement this objective. However, as a perennial subject of North-South disagreement, there is no consensus on the relevant details or mechanisms for deploying intellectual property rights to effectuate the objective. The United Nations Framework Convention on Biological Diversity (CBD) signifies a global regime embodying the ideals of incentivising the traditional custodians of the wild habitat as well as equitable sharing of the benefits of biodiversity. Arguably, it marks an end to the idea of regarding traditional knowledge as part of the global intellectual commons. This thesis contends that the CBD regime carries with it the burden of unresolved North-South perspectives on intellectual property rights. It argues that the heart of the conflict is the reluctance of the North to accord intellectual property status to traditional knowledge. This is partly because of the latter's informal nature but most importantly it derives from an inherent geo-political ideological conflict on the subject of intellectual property rights. Presently, the recognition of rights over traditional knowledge is approached on a sui generis basis. This thesis takes the position that the approach with its several limitations is not persuasive. It contends that on the merits, traditional knowledge is, and ought to be recognised as a subject matter of intellectual property rights. The recent elevation of intellectual property (a traditional subject matter of national law) to the international level under the WTO/TRIPs Agreement further undermines traditional knowledge. This has posed a setback not only to the global biodiversity conservation initiative, but also to the quest for equitable allocation of its dividends. It is my thesis that a national approach offers a better option for accommodating the intellectual property status of traditional knowledge and consequentially for advancing the quest for biodiversity conservation as well as equitable allocation of the dividends arising therefrom.
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27

Veiga, Pedro Filipe Duarte Alves da. "Recreational shore fishing in southern Portugal: biological and socio-economic aspects and perspectives for management". Doctoral thesis, 2012. http://hdl.handle.net/10400.1/6800.

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Although overfishing is a concern for many fish stocks, it was for a long time only associated with commercial fishing exploitation, with less or no attention being given to the recreational fisheries. Recent research has shown however that the impact of recreational fishing on particular species can be considerable, and that the recreational harvest needs to be taken into account if fisheries are to be accurately assessed and effectively managed. In Portugal, the first recreational fishing regulations were only recently implemented. However, mirroring other European countries, regulations lacked scientific support, and specific knowledge of the activity was limited to a few studies with limited coverage. This thesis aimed to characterize the biological and socioeconomic aspects of the recreational shore angling activity in southern Portugal, to investigate whether the regulations in place were adequate and effective, and to provide recommendations for improved management and conservation of the inshore fisheries resources. A combined aerial-roving survey was conducted to gather data on fishing effort, catch, fishing trips and socioeconomic aspects (including anglers’ perceptions of regulations) of the recreational angling activity. The analysis of anglers’ catches suggested that compliance with daily bag limits was high, with less than 0.5% of creels exceeding the 10 kg angler-1 day-1 bag limit. Overall, 11.5% of the retained fishes were undersized, but non-compliance with minimum size limits was found to be high for some species (e.g. seabass, 73% undersized). In terms of the impact of recreational shore angling, the total estimated catches corresponded to less than 1% of the commercial landings for the same period (shared species). However, shore angling catches for white sea bream (Diplodus sargus) were found to be considerable, corresponding to 65% of the commercial landings (39.4% of total catch). In terms of anglers’ perceptions about the recreational fishing regulations in Portugal, the present study has shown that the majority of anglers accepted the existence of some kind of SRF regulations, but in general there was a partial or total disagreement with the recreational fishing restrictions recently put in place. Most anglers perceived themselves as not being involved in the decision-making process and claimed that some restrictions lacked a meaningful rationale (e.g. prohibition of fishing from piers/jetties). Fishers’ awareness with regard to specific aspects of the restrictions (such as the rationale for minimum size limits) was found to be very limited. During the same period, catches from sport fishing competitions were examined to test for differences with the recreational activity in terms of catches, and evaluate long term trends in catch and mean size of fish. Catches of the sport fishing competitions were found to be different from those observed for recreational fishing, being dominated by different species (e.g. garfish, mullets), and suggesting different fishing strategies of the the two types of anglers. High percentages of undersized fish were observed to be captured (and retained) during the competitions (in particular seabass, with 100% undersized), probably as a result of a single allowable minimum size (AMS) of 15 cm for all species in use in competitions. Lastly, catch and release fishing experiments were carried out to assess post-release mortality of three recreationally important species: two banded sea bream Diplodus vulgaris; black sea bream Spondyliosoma cantharus; and gilthead sea bream Sparus aurata. Post-release mortalities were found to be low (0-12%). The main predictor of mortality for Sparus aurata was anatomical hooking location, with 63% of the fishes that died being deeply hooked. The results support the release of fish, either from mandatory (e.g. minimum landing sizes) or voluntary practices. In summary, this thesis has demonstrated that the impact of recreational fishing for particular species is significant and needs to be taken into account for more effective management and stock assessment purposes. It has also highlighted several management issues that should be addressed in order to promote more adequate regulations in the future and prevent noncompliance issues. A periodic monitoring of the recreational fishing activity including all fishing modes (i.e. spear fishing, boat, and shore angling) would also be beneficial to ensure a timely knowledge on the global recreational fishing activity and support future management actions.
O problema de sobrepesca que se tem assistido em muitas partes do globo foi, durante muito tempo, apenas associado à pesca comercial, com pouca ou nenhuma atenção dirigida à potencial contribuição da pesca recreativa. Estudos recentes têm demonstrado, no entanto, que o impacto da pesca recreativa em algumas espécies em particular pode ser considerável e que, como tal, avaliações e gestão de recursos que não incluam esta componete podem ser enviesadas e ineficazes na protecção dos recursos. Em Portugal, as primeiras medidas restritivas para a pesca recreativa só recentemente foram implementadas. No entanto, e à semelhança do que se verificou em outros países Europeus, as restrições careceram de suporte científico, dada a escassez de estudos em relação à actividade até ao momento. Este projecto, dirigido à pesca recreativa de costa (PRC) no sul e sudoeste de Portugal, teve como objectivos principais: 1) caracterizar a actividade nas suas vertentes biológica e socioeconómica; 2) avaliar a eficácia e a aceitação da legislação no que diz respeito às várias medidas restritivas; e 3) fazer recomendações que permitam uma melhor gestão e conservação dos recursos costeiros em Portugal. A caracterização da pesca recreativa de costa foi efectuada com recurso a duas metodologias complementares: 1) entrevistas nos locais de pesca, para obtenção de informação sobre as saídas de pesca (p.ex. capturas) e informação socioeconómica; e 2) levantamentos aéreos de distribuição de pescadores, para obtenção de dados de esforço de pesca. A análise das capturas dos pescadores indicou que, no geral, o cumprimento dos limites diários de pesca (10 kg pescador-1 dia-1) foi elevado, com apenas 0.5% dos pescadores entrevistados a excederem este limite. Em relação aos tamanhos mínimos de captura, verificou-se que apenas 11,5% dos peixes retidos pelos pescadores estavam abaixo do tamanho mínimo de desembarque estabelecido por lei. Não obstante, para algumas espécies como o robalo em particular, a percentagem de indivíduos abaixo do limite legal para espécie (36 cm) foi elevada (73%). A nível do impacto da pesca recreativa de costa, verificou-se que as capturas totais anuais estimadas representaram menos de 1% das quantidades desembarcadas pela pesca comercial, para o mesmo período e para espécies capturadas por ambos os tipos de pesca. Uma análise por espécie indicou no entanto que as capturas de sargo legítimo pela pesca recreativa de costa foram consideráveis, correspondendo a 65% dos valores comerciais desembarcados para a mesma espécie (39,4% das capturas totais). Em termos das opiniões dos pescadores em relação a legislação específica para a pesca recreativa, verificou-se que a maioria dos pescadores aceitava a existência de algum tipo de legislação, mas que em geral não concordava com as actuais restrições. Uma grande parte dos pescadores considerou que esta legislação tinha sido desenvolvida sem envolvimento dos mesmos, e que algumas das restrições (p.ex. proibição de pesca nos molhes) careciam de justificação fundamentada. Numa mesma fase foram também investigadas as competições de pesca desportiva de costa a decorrer no sul de Portugal, visando identificar diferenças com a vertente recreativa, e avaliar tendências de longo prazo nas capturas a partir de dados históricos. Verificou-se que em geral as competições de pesca desportiva eram diferentes das da pesca recreativa a nível do número de espécies capturadas e das espécies mais importantes nas capturas (no caso das competições: taínhas e peixe-agulha). Tal diferença atribuiu-se à possibilidade de uma estratégia diferente entre os dois tipos de pescadores relativamente às espécies-alvo. As competições de pesca desportiva foram também caracterizadas por grandes percentagens de espécimens abaixo do tamanho mínimo de desembarque (robalo em particular, 100% abaixo do limite), possivelmente como resultado da utilização de um único tamanho mínimo de 15 cm para todas as espécies. No último estudo, realizaram-se pescas experimentais para testar as taxas de mortalidade póslibertação de três espécies identificadas como importantes na pesca recreativa de costa do sul de Portugal: Safia Diplodus vulgaris; Choupa Spondyliosoma cantharus; e Dourada Sparus aurata. As taxas de mortalidade observadas foram em geral baixas (0-12%). A análise por modelos aditivos generalizados indicou a localização do anzol como o principal predictor da mortalidade, sendo que em 63% das douradas que morreram o anzol se encontrava profundamente alojado no tubo digestivo (estômago, esófago). Estes resultados suportam a decisão de libertar o peixe capturado, voluntariamente ou por medidas restritivas legais. Em suma, neste projecto demonstrou-se que o impacto da pesca recreativa de costa em algumas espécies é significativo, em particular o sargo, devendo ser tido em conta para efeitos de avaliação de gestão de recursos. Foram também realçados vários problemas com a corrente legislação que deveriam ser devidamente analisados de forma a promover medidas de gestão mais adequadas e prevenir futuras situações de incumprimento da lei. Como recomendação final, considera-se que uma monitorização periódica da pesca recreativa em Portugal, nas suas várias modalidades (pesca submarina, pesca embarcada e pesca de costa) e dimensões (biológica e socioeconómica), seria benéfica para um acompanhamento adequado da dinâmica da actividade, e suporte de futuras medidas de gestão.
Fundação para a Ciência e a Tecnologia (FCT)
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Perez-Brumer, Amaya Gabriela. "HIV Biomedical Prevention Science and the Business of Gender and Sexual Diversity". Thesis, 2019. https://doi.org/10.7916/d8-n6cg-5t39.

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This dissertation examines the political economy of HIV biomedical prevention research—largely designed in the global North but conducted in the global South—and its implications for people of diverse genders and sexualities. As a recognized global leader in HIV biomedical prevention research among people categorized as men who have sex with men (MSM) and transgender women, Peru offers a key site in which to explore the increasing focus on gender and sexual identity as a strategic area for extractive research practices. This phenomenon has become particularly visible in the epidemic’s 4th decade, which has emphasized the pursuit of biomedical prevention strategies. Building on nine years of previous experience working inside HIV biomedical prevention studies, this project involved 24 months of ethnographic research, including participant observation; 110 interviews with scientists, study staff, and research subjects; 10 focus groups; and analyses of relevant scientific publications. This study presents four key findings. First, US and Peruvian researchers’ historical and continued entanglement primed Peru to become a hotbed of HIV biomedical prevention research. In this context, population categories imported from the global North have served as powerful tools to sustain a booming local research market, which produces data that aligns with the global demands of the HIV industry. Second, on the ground, research begets more research rather than institutionalized HIV prevention technologies, creating a sustained enterprise in which issues of compensation, value, and labor shape the science. The commodification of gender and sexually diverse identities operates here in two ways: as a mechanism to access particular kinds of bodies and associated HIV risk data, and as a mechanism by which to claim expertise in the HIV prevention research industry for both researchers and community members. Third, Peruvians classified as MSM and transgender women are afforded only temporary access to cutting-edge strategies to prevent HIV, limited to study participation. The result is a sustained pool of people in need of HIV care primed to support the HIV biomedical research economy. Finally, this project illuminates a key paradox within the industry’s contemporary focus on gender and sexual diversity in HIV prevention science. This focus creates the impression that progressive health politics marked the field, while obscuring and absolving ongoing forms of exploitation and unequal gains embedded within it.
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Glenk, Klaus [Verfasser]. "Economic valuation of biological diversity : exploring non-market perspectives in the vicinity of the Lore-Lindu National Park in Indonesia's Central Sulawesi Region / vorgelegt von Klaus Glenk". 2006. http://d-nb.info/985524839/34.

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Park, Seung Eun. "Essays on the Economics of Higher Education and Employment". Thesis, 2019. https://doi.org/10.7916/d8-tg08-fe98.

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This dissertation studies legal and institutional policies that help to reduce the barriers to educational attainment and employment. The first chapter examines the effect of availability of juvenile record laws on education attainment and employment using state statue revisions after the passage of the federal Second Chance Act. The second chapter examines enrollment patterns of students who drop out from community colleges and identify four typologies of college dropouts and important factors that contribute to college success. The third chapter estimates the impact of federal Pell Grant eligibility on financial aid packages, labor supply while in schools, and academic outcomes for community college students. The three chapters together shed light on how federal, state, and institutional policies can help reduce the academic and employment barriers for the marginalized population in the United States.
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31

Maake, Mphapantsi Eldred. "Population genetic structure of small holder dairy cattle herds in South Africa using SNP markers". Thesis, 2020. http://hdl.handle.net/10386/3453.

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Thesis (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2020
The smallholder dairy sector in South Africa is characterized by a low input production system and poor animal productivity. Research has been carried out to benchmark cow productivity on smallholder dairy herds; however, there is a paucity of information on the current status of breeding practices and the genetic consititution of cattle used in this production system. This information is vital for the development of sound and sustainable breeding programs for SHD production, which can have an enormous positive impact on food security and rural livelihoods. Thus, the aim of this study was to evaluate the levels of genetic diversity and population structure in South African smallholder dairy (SHD) herds using single nucleotide polymorphism (SNP) markers. A total of 192 animals from SHD dairy herds were genotyped using the GeneSeek® Genomic Profiler (GGP) 150K-BeadChip. Four specialized dairy breeds included the Ayrshire(n = 200), Holstein(n = 231), Jersey (n = 224) and Nguni (n = 209) were used as the reference populations. The mean MAF values ranged from 0.30 Ayshire (AYR), Jersey (JER), and Nguni (NGI) to 0.31 Holstein (HOL) and SHD between the populations. There were slight differences in the levels of genetic diversity ranged between 0.39 (JER and NGI) to 0.40 (AYR, HOL, and SHD). A moderate level of inbreeding (0.02) was observed in the SHD population, which results in high genetic diversity among this herds. Principal Component Analysis (PCA) revealed four homogeneous clusters comprising of AYR, HOL, JER, NGI, and a heterogeneous cluster of the SHD. The heterogeneity observed in the SHD population indicates widespread crossbreeding. The model-based cluster analysis corresponded with the PCA and pointed out the predominance of HOL, JER, with marginal gene flow from the AYR and NGI. These results have provided a useful insight into the genetic structure and prevailing breeding practices on South African SHD herds.
National Research Foundation (NRF), Agricultural Research Council (ARC) and University of Limpopo (UL)
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32

Venter, Theo Muller. "The right sized cow for emerging and commercial beef farmers in semi-arid South Africa : connecting biological and economic effeciency". Diss., 2018. http://hdl.handle.net/10500/26004.

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Text in English
Cow size influences biological efficiency of individual animals, which influences herd composition and stock flow. This in turn influences the economic efficiency of the herd. This research followed the thread from animal size, to biological efficiency, to economic efficiency for beef cattle production under a typical production system in semi-arid South Africa. Cattle were grouped into three groups namely small, medium and large cattle, with mature weights of 300kg, 450kg and 600kg respectively. The net energy requirements of individual cattle were calculated for maintenance, growth, lactation and foetal production, for each of the three sizes. Growth rates, milk yield, reproduction rates, and management practices were assumed from existing research. Next the stock flow for a herd of small, medium and large cattle were calculated from the above. Income and expenses as commonly used in the research area were calculated from the stock flow. Gross profit above allocated costs were subsequently calculated for the three herds under the above-mentioned conditions. When assuming similar reproduction and growth rates for small, medium and large mature cattle, the following results were obtained: more heads of small cattle could be held on a set resource base, but the total live weight of a herd of large cattle that could be held on the same resource base was greater. This was mostly due to proportionately lower maintenance energy requirements in the herd of large cattle. In the simulation in this study, maintenance energy requirements for the herd of large cattle was 71.2%, compared to 72.0% for the herd of medium cattle and 73.1% for the herd of small cattle. Income from the herd of small cattle was the lowest, as less kilograms of beef were available to sell. Allocated costs for the herd of small cattle were the highest, due to a large number of expenses being charged per head of cattle. As a result, the herd of large cattle were more economically efficient than their smaller counterparts. Income above allocated costs for the herds of large, medium and small cattle were R1,182,865, R1,085,116 and R946,012 respectively. Larger cattle generally have a lower reproduction rate under similar conditions. No equation exists that directly links size to reproduction rates, especially considering the vast number of variables that influences reproduction rates. However, in the form of scenarios, it could be calculated that, given a reproduction rate of 80% for mature small cattle, when reproduction rates of large cattle were 24.7% lower than that of small cattle and the reproduction rates of medium cattle were 15.4% lower than that of small cattle, the large and medium herds became less profitable than the small herd. Smaller cattle mature faster than larger cattle which provides the opportunity for early breeding. When small cattle were bred early, at 15 months, at a calving rate of only 44.5% it was more profitable than when the same cows were bred at 24 months. When medium cattle were bred at 15 months, a calving rate of 37.0% was needed to be more profitable than when they were bred at 24 months. Even when the herd of small cattle were bred at 15 months with a reproduction rate of 100%, it could still not match the profitability of the herd of large cattle bred at 24 months given the reproduction rates of all other classes of animals were similar. When the herd of medium cattle were bred at 15 months, at a calving rate of 53.7%, it matched the profit of the herd of large cattle that were bred at 24 months, when the reproduction rates of other classes were equal. Scenarios were considered were feed intake was limited. When feed was limited to a specific amount, smaller cattle were more biologically efficient and cattle with potential for small mature sizes would grow to a larger size than cattle with potential for medium and large mature sizes. When feed was limited by a factor of the calculated energy requirements of small, medium and large cattle, large cattle were more effective. This is because large cattle use proportionately less energy for maintenance, which allows more energy to be allocated to growth, lactation and foetal production. When energy was limited to an amount per unit of metabolic weight, small cattle were more efficient than medium and larger cattle in the growth and production phases. Small, medium and large cattle were equally efficient (or inefficient) in the maintenance and lactation phases. Energy requirements of cattle in South Africa are commonly calculated using the Large Stock Unit (LSU). The LSU typically overestimates energy requirements for cattle, except in the lactation phase. When using the LSU to match small, medium or large cattle to a resource base, the LSU overestimates energy requirements of large cattle proportionately more than that of small and medium cattle. This is excluding the lactation phase, where energy requirements for all three sizes are underestimated and that of large cattle underestimated proportionately more. There are more considerations when matching cow size to managerial practices. A smaller body size is a natural adaptation to a semi-arid environment and this adaptation can be expressed in different ways. The number of animals on a resource base has implications on management practices. Having more heads of cattle on a resource base increases genetic variation of the herd, allowing for genetic progress to be made faster than in herd of fewer cattle.
Agriculture and  Animal Health
M.Sc. (Agriculture)
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33

Oliveira, Miguel Tiago Cantiga Lopes de. "The role of artificial reefs to promote biodiversity and sustainability of the ecotourism in Cape Verde: ecological, biological and management aspects". Doctoral thesis, 2016. http://hdl.handle.net/10400.1/8996.

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Tese de doutoramento, Ciências do Mar, da Terra e do Ambiente, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016
This multidisciplinary study aimed to assess the impact of artificial reefs (ARs) deployment off Santa Maria (Sal Island), to promote biodiversity and sustainability of the ecotourism in Cape Verde.
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34

Maina, Peter Njuguna. "Recognition, measurement and reporting for cap and trade schemes in the agricultural sector". Thesis, 2016. http://hdl.handle.net/10500/21522.

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The pressing global demand to transform to a low-carbon business community, which is required by the urgency of mitigating climate change, significantly alters the operating procedures for carbon emitters and carbon revenue generators alike. Although agricultural activities are not considered as heavy carbon emission source, the increased public focus on climate change has catapulted the exploitation of sustainable agricultural land management mitigating strategies as intervention by the sector. Additionally, the focus on market-based mechanism to address climate change, which has led to the evolution of cap-and-trade schemes, makes the agricultural sector become a source of low-cost carbon offsets. However, the fact that cap-and-trade schemes in the agricultural sector are voluntary has resulted into not only very diverse farming practices but also diverse accounting practices. The consequences of the diversity practices are that, the impacts on financial performance and position are not comparable. Therefore, the overall objective of this study was to investigate the recognition, measurement and disclosure for cap-and-trade schemes in the agricultural sectors This study was conducted through literature reviews and empirical test. A qualitative research approach utilising constructivist methodology was employed. Primary data was collected in Kenya by administering three sets of semi-structured questionnaires to drafters of financial statements, loan officers and financial consultants. Secondary data involved content analysis of financial statements and reports of listed entities across the globe. It was established that proper accounting for cap-and-trade schemes adaptation activities is critical to the success of an entity’s environmental portfolio. Additionally, a model for valuing an organisation's carbon capture potential as suggested by this study enables entities to better report the impact of the adaptation activities on the financial performance and financial position. The outcome of this study enables entities to integrate the carbon capture potential on an entity sustainability reporting framework.
Colleges of Economic and Management Sciences
D. Phil. (Accounting Science)
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35

Sethusa, Mamadi Theresa. "A molecular phylogenetic study and the use of DNA barcoding to determine its efficacy for identification of economically important scale insects (Hemiptera: Coccoidea) of South Africa". Thesis, 2014. http://hdl.handle.net/10210/11398.

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Ph.D. (Zoology)
Scale insects, plant pests of quarantine importance, with specialised anatomy and unresolved phylogenetic relationships, are responsible for major economic losses to South Africa and its trading partners. These losses may reach critical levels if the pests are not timely identified and controlled. They are currently identified based on published keys of adult females, a process that takes three days to two weeks depending on the family and the life stage of interception. In addition, agricultural commodities are often contaminated with different life stages, males or damaged specimen of these pests, making identification difficult or impossible. As a result, shipments of agricultural produce are often rejected and trade disrupted. Furthermore, pest invasions do not only occur by importation via formal channels. At times pests cross boarders as contaminants of undeclared material and may again spread on their own as they naturally expand their range. This expansion may be negatively or positively influenced by other factors such as climate change. Resolving the challenges associated with identification, phylogenetic relationships and the limited knowledge of the effects of climate change on distribution range of scale insects are the main goals of this study. Specifically (i) the development of a rapid method of species identification, (ii) the relationship between and within three major scale insect families the Coccoidea, Diaspididae and Pseudococcidae and (iii) the effect of climate change on the future distribution range of scale insects in South Africa were explored...
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Smith, Adriaan Frederik. "Perceived influence of inequality on the career development of emerging adults in South Africa". Diss., 2018. http://hdl.handle.net/10500/26246.

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After the transition from the Apartheid government to the first democratically elected government of South Africa in 1994, massive challenges of inequality had to be addressed. The career development and ability of those individuals who were discriminated against, to participate economically, are still a challenge today which indicate that past inequalities have not yet been addressed. The study aimed to gain a deeper understanding of how inequality influence the career development of emerging adults in South Africa. The findings indicated that the legacy of inequality in South Africa is still a highly influential factor in the career development of emerging adults with regards to the lack of mentorship and access to information experienced. The inability of South Africans as a collective to address the legacy of inequality also influence prospects for career development with regards to emerging adults not being financially able to gain access to career development opportunities.
Industrial and Organisational Psychology
M. Com. (Industrial and Organisational Psychology)
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37

Hammer, Michael. "A molecular genetic appraisal of biodiversity and conservation units in freshwater fishes from southern Australia". 2008. http://hdl.handle.net/2440/50448.

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The freshwater fish fauna of southern Australia is characterised by low species richness and high endemism in groups displaying southern temperate, temperate-subtropical or temperate-tropical distributions. Comparatively few studies in Australia have incorporated modern molecular techniques to delineate species boundaries and define within-species conservation units. This is problematic because freshwater fishes are likely to show high levels of cryptic speciation and marked spatial sub-structure, and is information which is needed to conserve biological diversity and maintain the integrity of ecological communities and processes. The current study uses a ‘combined evidence’ approach, led principally by a set of nuclear genetic markers (allozymes), to assess species boundaries, spatial sub-structure and conservation units in obligate freshwater fishes from southern Australia. A literature review (Chapter 2) concerns the nature and effects of fragmentation in freshwater environments. It considers the implications for freshwater fishes and the types of extrinsic and intrinsic characteristics, both natural and human accelerated, that might drive population fragmentation and divergence. This theoretical framework is then applied to a suite of six largely co-occurring species groups with contrasting biological characteristics, and derive hypotheses about expected levels of genetic divergence across and within different drainages. Major findings Species of Retropinna (Chapter 3) are widespread and generally regarded as ‘common’ and mobile. Allozyme analyses revealed species-level and population-level sub-divisions, including five distinct species with contiguous ranges and no evidence of genetic exchange. Three occur along the eastern seaboard (including three instances of sympatry), another in coastal and inland southeastern Australia and Tasmania, and a fifth in the Lake Eyre Basin. There is no indication of a simple ‘tasmanica’ versus ‘semoni’ dichotomy, but instead a complex pattern involving discrete clusters for the Upper Murray plus Darling rivers, Lower Murray, Glenelg River and Tasmanian regions. These findings have implications for biodiversity, conservation and ecology. This chapter has been published in modified form (Marine and Freshwater Research 58, 327- 341). Nannoperca obscura (Chapter 4) is a small demersal fish with specialised habitat requirements. It is under threat of extinction, particularly in the western section of its range. Combined nuclear and matrilineal genetic data identified congruent within-species sub-structure, divided by patternsof distribution and biogeography. Four monophyletic mtDNA lineages, each distinct at multiple nuclear loci, indicate four Evolutionarily Significant Units (ESUs), namely (1) Lake Alexandrina in the Murray-Darling Basin (MDB), (2) Glenelg River, Millicent Coast River Basin and the outlying Mt Emu Creek, (3) Merri River and associated coastal streams, and (4) the eastern range section. Additional genetic and ecological data support multiple Management Units (MUs) within ESUs for individual or groups of river basins separated by marine barriers. Nannoperca australis (Chapter 5) has a similar character to its aforementioned congener, except that it occurs across a much wider area. Although generally common, particular populations are threatened, especially in the MDB. Allozyme analyses of 57 populations confirm the presence of two divergent species, with an eastern species containing two ESUs: (1) Gippsland and Flinders Island, and (2) Ansons River in northeastern Tasmania. The western species shows sub-structure across its range, including a separation of MDB and coastal populations as two heterogenous ESUs. The Lower Murray region (Mount Lofty Range streams and the Lower Lakes) harbours a remarkable level of between- and within-population diversity, underscoring its importance for conserving evolutionary potential. Mogurnda adspersa (Chapter 6) has been presumed extinct in South Australia since the early 1970s and has also been assumed lost from the southern MDB. This chapter reports on the rediscovery of M. adspersa from a wetland near the terminus of the Lower Murray, some 2500 river kilometres from the nearest known population. The nature and basic ecology of this population is documented, but the combined effects of drought and water abstraction recently have led to the probable extirpation of the wild population. A combined allozyme and mtDNA dataset confirmed the ‘nativeness’ of the population as a distinct sub-population (and MU), with a moderate level of allele heterogeneity. This information provides a platform for captive breeding as a conservation measure. The endemic genus Philypnodon (Chapter 7) contains two nominal species: P. grandiceps and the long recognised but only recently described P. macrostomus. The former is considered widespread and common (near ubiquitous), whereas the latter is more patchily distributed. Some tolerance to marine conditions is indicated, suggesting that there may be less sub-structure, but allozyme analyses of 269 individuals indicate the presence of multiple, species-level taxa within both described species. This obscures interpretations of existing ecological data. Although the presence of genetically-similar populations within and across some drainage divides indicates higher levels of gene flow, the pattern is complex and suggests historic genetic exchange between some but not other geographically-adjacent taxa. The freshwater blackfish genus Gadopsis (Chapter 8) has been a problem group for taxonomists, and it is unclear where the group is placed phylogenetically and how many species occur. Northern and southern forms on respective sides of the Great Dividing Range have been proposed, but with limited supporting evidence. Its dispersal ability (hence predicted genetic structure) is obscured by opposing life-history traits, including large body size (i.e. good swimming ability) versus habitat specialisation, demersal larvae and restricted home ranges. This chapter provides a genetic overview incorporating 61 locations across the range, and demonstrates unequivocally the presence of distinct northern and southern species of G. ‘marmoratus’. Moreover, distinct genetic discontinuities involving geographically abutting lineages indicate the likely presence of multiple ESUs within each species. A comparison of the allozyme data with previous mtDNA studies also identified two ESUs within G. bispinosus. Overall, considerable complexity is demonstrated signalling the need for a review of how the southern Australian fish fauna should be viewed, studied and protected. The genetic data also provide insight into the interplay of intrinsic biological characters (e.g. dispersal ability, population ecology) with historic and contemporary extrinsic environmental factors (e.g. fragmentation, biogeographic processes). Comparisons between and within traditionally-defined species are problematic, however, owing to multiple species-level splits and other genetic divisions that may have matching biological counterparts. Together with other reports in the literature, the findings presented herein have significant conservation implications, particularly given the rapid pace of human-mediated change in some regions that house high species and genetic diversity and unique evolutionary components, notably southeastern Queensland (especially the Mary River) and the lower River Murray in South Australia. Other regions displaying high genetic substructure or divergent populations include the Clarence River and Lachlan River in New South Wales; Gippsland, Goulburn River, Glenelg River and Mt Emu Creek in Victoria, and the Macquarie River and Ansons River in Tasmania.
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Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2008
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Maas, Bea. "Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield". Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E77-5.

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39

Koutouki, Konstantia. "The placebo effect: international patent law and the protection of traditional plant medicine". Thèse, 2007. http://hdl.handle.net/1866/2772.

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Une préoccupation essentielle traverse cette thèse: l'indifférence systémique de la Loi internationale sur la propriété intellectuelle a l'égard des savoirs traditionnels autochtones. De manière générale, un écart semble d'ailleurs croissant entre l'importance des accords internationaux sur les questions d'intérêt commercial et ceux de nature sociale. Les savoirs traditionnels autochtones sur les plantes médicinales sont particulièrement désavantagés dans ce système dichotomique puisqu'ils sont non seulement à l'origine d'énormes profits commerciaux mais se trouvent aussi au cœur de multiples croyances propres à ces sociétés. L'Accord sur les aspects des droits de propriété intellectuelle qui touchent au commerce (ADPIC) de l'Organisation mondiale du commerce (OMC) a cristallisé le souci de la législation internationale à l'égard d'une protection efficace des intérêts commerciaux. Deux années auparavant, la Convention sur la diversité biologique (CDB) était signée, traduisant une préoccupation à l'égard du développement durable, et elle devenait le premier accord international à tenir compte des savoirs traditionnels autochtones. On considère souvent que ces deux accords permettent l'équilibre du développement commercial et durable, requis par l'économie internationale. Après plus ample examen, on a plutôt l'impression que l'idée d'une CDB défendant, avec succès et efficacité, la nécessité du développement durable et des savoirs traditionnels autochtones contre les pressions opposées de l'ADPIC et de l'OMC est, au mieux, simpliste. La thèse explore également la fonction de la Loi sur les brevets dans la création d’industries, notamment pharmaceutique, et la manière dont ces industries influencent la législation nationale et en particulier internationale. De même, elle traite du rôle que jouent les brevets dans l'affaiblissement et la dépossession des peuples autochtones dotés de savoirs traditionnels sur les plantes médicinales, conduisant à une situation ou ces savoirs sont marginalisés ainsi que leurs détenteurs. La thèse aborde les failles institutionnelles du système juridique international qui permet une telle situation et indique l'urgente nécessité d'examiner attentivement les inégalités économiques et sociales au Nord comme au Sud, et non seulement entre eux. Finalement, la thèse suggère que la législation internationale gagnerait à s'inspirer des diverses traditions juridiques présentes à travers le monde et, dans ce cas particulier, peut être les détenteurs des connaissances traditionnelles concernant les plantes médicinales seront mieux servi par le droit des obligations.
The underlying theme of this thesis is the systemic indifference that exists within international intellectual property law towards Indigenous traditional knowledge. In general, there appears to be a widening gap between the importance international law accords to matters of commercial interest and those of a social nature. Indigenous traditional knowledge of medicinal plants is especially disadvantaged in this dichotomous system since it is not only representative of enormous commercial profits but it is also the core of many Indigenous belief and social systems. The crystallization of international law's preoccupation with the effective protection of commercial interests came in the form of the Trade Related Intellectual Property Rights (TRIPS) agreement incorporated into the World Trade Organization (WTO). Two years previously, the Convention on Biological Diversity (CBD) was signed, reflecting international law's perceived dedication to sustainable development and became the first international treaty to address Indigenous traditional knowledge. These two pieces of international law are often seen as balancing the commercial and sustainable development needs of the international economy. Upon further examination however, one is left the impression that the idea of the CBD effectively and successfully defending the needs of sustainable development and Indigenous traditional knowledge against pressure to the contrary from TRIPS and the WTO is simplistic at best. The thesis also explore the role patent law plays in the creation of modern industries, such as the pharmaceutical industry, and how these industries are able, through the power gained via patent law, to influence national and especially international legislation. Equally, it deals with the role patents play in disempowering peoples with Indigenous traditional knowledge of medicinal plants leading to a situation where such knowledge is marginalized along with its bearers. The thesis addresses the institutional shortcomings of the international legal system that allows such a situation to exist and suggests an urgent need to closely examine the social and economic inequalities within the North and South and not just between them. Finally the thesis suggests that international law needs to be guided by the many legal traditions available worldwide and in this particular case perhaps contract law is better suited to the needs of Indigenous traditional knowledge holders.
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