The role of industrial policy in pursuing climate change mitigation objectives in South Africa

Includes bibliographical references (p. 81-87).This thesis has drawn on Fine and Rustomjee's (1996) notion of the Minerals-Energy Complex (MEC) as a tool to analyse the relationship between industrial policy, energy use, and climate change mitigation policy in the South African context. The analysis finds that the South African economy has clearly developed in response to sets of industrial incentives offered both pre- and post-apartheid, which have structured the economy in such a way that electricity-intensive industry have come to dominate exports and investment in the country, but with very little positive effect on socio-economic development. This structure has a detrimental effect on possible mitigation actions; firstly because with the current development trajectory, it will be very challenging to meet mitigation targets as laid out in the country's Long-term Mitigation Scenarios (LTMS), and secondly because the mitigation wedges outlined in the LTMS will require significant shifts in the approaches, types and range of industrial policy measures that the country uses

Effects of Prescribed Fire on Mammoth Cave National Park’s Oak-Hickory Vegetation

Mammoth Cave National Park contains a spectacular suite of plant communities; many of which are dependent on wildland fire as a disturbance process for their preservation. Over a third of the park is dominated by oak-hickory forests and woodlands. Fire is a fundamental process in the development and maintenance of this important community type. Since the park’s first prescribed fire in 2002, 16,700 acres of forest, woodlands, and barrens have been treated with prescribed fire. Initial goals for the prescribed fires were to reduce the density of tree saplings in the understory and increase the cover of herbaceous herbs in the understory. After a single burn, wildland fuel loading was reduced by 18%, density of understory trees (dbh \u3c 15cm) was reduced by more than 30%, and mean cover of graminoid species increased from \u3c 0.01% to 5.2%

The political economy of decarbonisation: exploring the dynamics of South Africa’s electricity sector

South Africa’s coal-dominated electricity sector, a key feature of the country’s minerals-energy complex, is in crisis and subject to change. This offers potential opportunities for decarbonisation. Despite positive examples of decarbonisation in South Africa’s electricity sector, such as a procurement programme for renewable energy, there are structural path dependencies linked to coal-fired generation and security of supply. Decarbonisation goes far beyond what is technologically or even economically feasible, to encompass a complexity of political, social and economic factors. Meanwhile, decision-making in electricity is highly politicised and lack of transparency and power struggles in the policy sphere pose key challenges. Such power struggles are reflected in national debates over which technologies should be prioritised and the institutional arrangements that should facilitate them

Fire and vegetation dynamics in the Cross Timbers forests of South-Central North America

Natural Resource Ecology & Mgm

2011 Vegetation Map for Mammoth Cave National Park

An accuracy assessment on a 2009 Vegetation Map of Mammoth Cave National Park produced by University of Georgia indicated inadequate reliability. As well, there were significant polygon boundary errors and unclassified polygons left blank on the map. With pressing need for a vegetation map to support the park’s Fire Management Plan (FMP), a derivative of the 2008 Landfire map was produced. Specifically, 24 categories were regrouped into 4 vegetation categories useful for the FMP. Barrens and Prairie Plantation categories were added as superimposed polygons, and the same approach was taken for both fire and storm-linked forest canopy gaps. Accuracy assessment data points were sampled on a random basis until the cumulative percent correct stabilized, indicating that the sample size was adequate. The final cumulative average for this map was 66% accurate, which will require enhanced field checking of prescribed fire plots. Funding will be sought for yet a new map

Fire Regimes, Buff alo and the Presettlement Landscape of Mammoth Cave National Park

The glory of the caves has long overshadowed other features of the park but the neglected upland landscape has its own extraordinary tale to tell. The park occupies a naturally fire sheltered setting in a historically vast fire landscape of barrens and woodlands once populated by Native Americans, bison and elk. The events above ground, spanning several thousand years before the arrival of Europeans and the subsequent explosive transformation of the land add rich layers of natural and human history, sadly neglected in development and interpretation of the park. This is the tale of the Barrens region itself. We constructed maps of historical fire frequency and vegetation, using 2,681 witness trees compiled from original land surveys beginning in 1781. Original fire frequency was interpreted using tree species and the degree of fire exposure of each tree in the landscape, e.g. fire exposed ridgetops, slopes or grassy barrens versus fire sheltered lower slopes, hollows and bottoms. The topographical setting was examined for characteristics related to fire spread such as pathways for fire fl ow, natural firebreaks and the size of fire compartments. The natural fire relations of each tree species and its distribution on the land were used to assign fire frequency to each site and region. Original fire regimes were complex and extreme: fire frequency ranged from nearly annual fi re in the true prairies and grassy woodlands on the limestone karst plain to the south – and on the plain between the Dripping Springs Escarpment and the Green River – to strongly fire sheltered hollows and bottoms within the park. The most fire sheltered sites were defined by the deep limestone bowls developed by karst topography – formed by millennia of dissolution of limestone by subterranean waters – and the rugged relief provided by the deeply entrenched Green and Nolin Rivers

Fire Frequency Effects on Vegetation of an Upland Old Growth Forest in Eastern Oklahoma

The purpose of this study was to determine the effects of prescribed fire frequency on the forest understory vegetation and forest composition in an old-growth forest of eastern Oklahoma. Prescribed fires over the past 20 years had a frequency of zero to five per decade. Tree density, basal area, overstory canopy, and understory plant cover was measured in each of eight treatment units. Sapling density and richness increase as fire frequency is reduced from five to zero fires per decade. Twenty years of low intensity fire at a frequency of five per decade is not sufficient for the reduction in tree density and canopy cover. While no herbaceous species were reduced in presence or cover by higher fire frequencies, many herbaceous species responded positively to increased fire frequencies. Frequent low-intensity fire maintains the dominance of fire tolerant oak species and the high biodiversity of herbaceous plants in the forest understory.Department of Natural Resource Ecology and Managemen

A Characterization of Different Spark Regimes for Ignition Delay Comparison with Conventional Spark Plugs

poster abstractThe introduction of plasma into combustion and ignition processes has continuously proved to be advantageous when compared to the conventional spark ignition in a wide range of categories. From the capability to ignite leaner mixtures and improve fuel economy to an effective reduction of hazardous emissions and ignition delay, the benefits of integrating non-equilibrium plasma can be utilized for numerous applications including hot jet ignition. Detailed design specifications for the electrode configuration, circuit schematic, and combustion rig are developed and presented. Using a CCD camera and high performance oscilloscope, this paper aims to identify, characterize, and compare the different effects of frequency and pulse width of a driver circuit on the plasma sparks quantitatively in terms of the current, voltage, and energy attributes. Four different plasma regimes are investigated with frequencies ranging from 5.44 Hz to 95.46 kHz and pulse energies ranging from 168 μJ to 14.42 J. The maximum voltage and current characteristics of the plasmas indicate a glow discharge referencing previous experiments. Future work is laid out for a comparison of the ignition progression between a non-thermal plasma system and a traditional spark with using Schlieren imaging

Regenerated sciatic nerve axons stimulated through a chronically implanted macro-sieve electrode

Sieve electrodes provide a chronic interface for stimulating peripheral nerve axons. Yet, successful utilization requires robust axonal regeneration through the implanted electrode. The present study determined the effect of large transit zones in enhancing axonal regeneration and revealed an intimate neural interface with an implanted sieve electrode. Fabrication of the polyimide sieve electrodes employed sacrificial photolithography. The manufactured macro-sieve electrode (MSE) contained nine large transit zones with areas of ~0.285 mm2 surrounded by eight Pt-Ir metallized electrode sites. Prior to implantation, saline or glial derived neurotropic factor (GDNF) was injected into nerve guidance silicone-conduits with or without a MSE. The MSE assembly or a nerve guidance conduit was implanted between transected ends of the sciatic nerve in adult male Lewis rats. At 3 months’ post-operation, fiber counts were similar through both implant types. Likewise, stimulation of nerves regenerated through a MSE or an open silicone conduit evoked comparable muscle forces. These results showed that nerve regeneration was comparable through MSE transit zones and an open conduit. GDNF had a minimal positive effect on the quality and morphology of fibers regenerating through the MSE; thus, the MSE may reduce reliance on GDNF to augment axonal regeneration. Selective stimulation of several individual muscles was achieved through monopolar stimulation of individual electrodes sites suggesting that the MSE might be an optimal platform for functional neuromuscular stimulation