Дисертації з теми "Forests and forestry Research Victoria"

Bibliography: leaves 135-143. An anthropological analysis of an industrial dispute that occurred within the East Gippsland forest industry, 1997-1998 and how the workers strove to acheive better working conditions for themselves, and to share in the wealth they had created.

University forests are very important in academic forestry education. They are not only used for the in-forest teaching but also serve for scientific research and public education for people to gain knowledge of forests. Besides these functions, the university forests can also provide social services, such as camping and recreation. People can go into the university forests to enjoy the nature and relax. Taking Beijing Forestry University as an example, this paper will describe the system of university forests in China, their categories, and their roles in forestry education, research and social services. Furthermore, this paper will also explain the development and management system of university forests, and key challenges to the university forests in the future.

Net primary productivity (NPP) is a key ecological parameter that is important in estimating carbon stocks in large forested areas. NPP is estimated using models of which leaf area index (LAI) is a key input. This research computes a variety of ground-based and remote sensing LAI estimation approaches and examines the impact of these estimates on modeled NPP. A relative comparison of ground-based LAI estimates from optical and allometric techniques showed that the integrated LAI-2000 and TRAC method was preferred. Spectral mixture analysis (SMA), accounting for subpixel influences on reflectance, outperformed vegetation indices in LAI prediction from remote sensing. LAI was shown to be the most important variable in modeled NPP in the Kananaskis, Alberta region compared to soil water content (SWC) and climate inputs. The variability in LAI and NPP estimates were not proportional, from which a threshold was suggested where first LAI is limiting than water availability.
xii, 181 leaves : ill. ; 28 cm.

Orientador: Sérgio Campos
Coorientador: Roberta Thays dos Santos Cury
Banca: Felipe Wanderley de Amorim
Banca: Renata Cristina Batista Fonseca
Resumo: A conversão de florestas naturais em pastagens, lavouras ou reflorestamentos homogêneos com espécies exóticas, pode influenciar processos ecológicos importantes alterando a dinâmica florestal. O trabalho teve como objetivo avaliar se reflorestamentos homogêneos de Pinus elliottii influenciam a remoção de sementes em uma vegetação secundária de Floresta Ombrófila Mista Montana adjacente. Assim, formulamos três hipóteses: (1) a remoção de sementes será maior na vegetação secundária de Floresta Ombrófila Mista Montana adjacente ao plantio de Pinus elliottii, em especial, onde as plantações se encontram em estágio inicial de desenvolvimento; (2) a remoção de sementes na vegetação secundária de Floresta Ombrófila Mista Montana será maior quanto mais distante da borda com plantio de Pinus elliottii; e (3) a remoção de sementes será diferente entre as espécies de Syagrus romanzoffiana, Araucaria angustifolia e Pinus elliottii. Foram selecionadas seis áreas de plantios de Pinus elliottii adjacentes a vegetação secundária de Floresta Ombrófila Mista Montana. Em cada área foram instalados cinco pontos amostrais, distribuídos ao longo de um transecto a uma distância de 0, 10, 25, 50 e 100 metros da borda florestal. Em cada ponto foram depositadas 13 sementes de cada espécie analisada. O monitoramento das sementes foi realizado após dois, sete, nove, 14 e 21 dias. No geral a taxa de remoção foi elevada para todas as espécies (100% para espécie Syagrus romanzoffiana, 98% para Pinus elliot... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Conversion of natural forests to pasture, crop or homogeneous reforestation with exotic species can influence important ecological processes by changing the forest dynamics. The objective of this work was to evaluate the effects of Pinus elliottii plantation on seed predation in a Mixed Ombrophilous Montane secondary forest. Thus, we formulate three hypotheses: (1) seed removal will be greater in the Mixed Ombrophilous Montane secondary forest adjacent to Pinus elliottii plantation, especially where the plantations are in early stages; (2) seed removal will be greater in the Mixed Ombrophilous Montane secondary forest farther from the forest edge; and, (3) seed removal will be different among Syagrus romanzoffiana, Araucaria angustifolia and Pinus elliottii species. Six Pinus elliottii areas adjacent to Mixed Ombrophylous Montane secondary forest were selected. In each area, five plots were distributed along 0, 10, 25, 50 and 100 meters from the forest edge. Were deposited 13 seeds by species in each plot. Seeds were monitored during two, seven, nine, 14 and 21 days. In general the removal rate was high for all species (100% for Syagrus romanzoffiana, 98% for Pinus elliottii and 49% for Araucaria angustifolia). Similarly, all distances from the forest edge showed high seed removal, however, Araucaria angustifolia showed reduced seed removal at the edge, with 33% of removal at 0 m against 70% at 100 m. These rates indicate the presence of forest-associated fauna, which may cause predation and/or secondary dispersal. The reduced seed removal of Araucaria angustifolia, a key species for Atlantic Forest, on the forest edge, may indicate losses in the wildlife associated with the forest edge adjacent to the homogeneous planting. In addition, the removal of Pinus elliottii seeds in the forest, if predated, may indicate a reduction of their invasive potential in natural areas.
Mestre

This is an interdisciplinary arts practice based PhD that incorporates fieldwork into its exploration of Abernethy Forest in Cairngorms National Park, and Culbin Forest in Morayshire, Scotland. The thesis explores how a contemporary arts practice can articulate a place’s multi-layered complexities and how processes of coming to know influence and impact on the kinds of artworks created. This way of working incorporates an innovative approach that draws on geographical, anthropological, historical and ecological sources, and includes the synthesis of a contemporary arts practice with an ethnographic element - more specifically participant observation, with foresters, ecologists and others - as a mode of gathering. Description and examination of encounters in the field give context to the artwork and provide additional knowledge that lends insight into management practices and the knowledge that these workers possess. The research constitutes an original contribution to investigations of the forests of Culbin and Abernethy and correspondingly innovative outputs. This research proposes that a contemporary arts practice can articulate and communicate aspects and elements of place in ways that offer insights to artists, geographers, anthropologists and others. Central to this is the idea that places are multi-layered, everchanging, embodied, active and containing complex ecological, sensorial and physical histories and presences. Communicating these understandings requires a multi-faceted way of working and multi-modal ways of articulation in recognition of place as an experiential field of investigation. The art produced forms a non-linear, multi-stranded body of work that emphasises the benefits of multiple formats within an arts practice. The thesis enhances and further complicates conceptualisations of place that in geography and anthropology are often restricted to academic writing and demonstrates how artists and others can usefully enlarge and expand the ways in which places can be articulated and rendered.

Forestry operations in Sweden can be traced a long way back in history. The overall emphasis has traditionally been on the forests’ economic or profitable role, even though they are also of great ecological and social interests. Nevertheless, the focus has shifted during the last decade due to the impact of sustainable development. A new Forestry Act has now provided the Swedish forestry with a new policy which is guided by two equally-weighted objectives; production and environmental concern. The European Union (EU) has also adapted to the direction of sustainable development. It places particular interest in the creation of sustainable coastal areas within the union.

The aim of the Bachelor of Science thesis was to investigate how Swedish coastal forest owners define their role in the creation of sustainable coastal forests. The study is built on interviews which were conducted with seven forest owners, all of whom have properties in the coastal zones of Östergötland and Kalmar. These two counties are situated in the south-eastern part of Sweden.

The study raises three different issues. The first is the manner in which the informants shape their knowledge of the existing forestry legislation, based on their identities and responsibilities. The second concerns the preconditions with which they are faced when managing their coastal forest properties and whether or not they see the new legislation as a shift in focus. The final issue highlights the importance of local knowledge and looks at the participation of the informants in the development of new regulations.

The following conclusions are drawn from the investigations. Many owners of forest properties do not identify themselves as forest owners; it is therefore important to be aware of this distinction which is made between being a forest owner and being the holder of a forest property. The coastal forest owners who were interviewed run their forests according to their individual situations. Because of this they do not appear to be part of any shift of focus within the Swedish forestry. As a result, they may not have a defined role in its development. This role would probably be clearer or greater if their local knowledge were more explicitly valuated.

Given the neoclassical assumptions of optimizing economic agents, perfect information, perfect competition, and productive efficiency, timber supply is a dynamic process. Different discrete-time dynamic timber supply models and their solution methods are compared and their common elements derived. A continuous-time model is derived, but not solved. The discrete-time timber supply model is then incorporated into a dynamic multi-sector model and a dynamic general equilibrium model. In the multi-sector model, all household's utility functions are aggregated into a single community utility function which is maximized subject to the technology of the economy. The technology for the forest sector is the same as in the discrete-time dynamic timber supply models. Wood is treated as an intermediate input into the production of consumer goods. The technology of the consumer goods sectors is based on the technology used in computable general equilibrium models. The optimal steady state problem for this model is discussed, and the solution for an example problem is presented. Disaggregating the utility function is necessary for modeling true general equilibrium. This greatly complicates the problem of Ending numerical solutions, but enriches the model considerably. The formulation of the general equilibrium model as an optimization problem is described, but proved rather difficult to solve. The optimal steady state problem can be solved using an algorithm developed by Scarf (1967) for finding fixed points of continuous functions. The fixed-point approach provides a reliable solution method and appears to have more potential for modeling departures from perfect competition than the optimization approach. The equivalence of the two approaches is discussed.
Ph. D.

In June of 2010, two permanent research plots were established in Forest Park, based on their differing proximities to downtown Portland, Oregon. As part of a long-term ecological research project that seeks to explore the ecological status and human thumbprint on this 5,100 acre forested reserve, the 2010 tree data was investigated for emergent compositional and spatial patterns. Stand composition, tree size, growth rates, and spatial patterns were analyzed, along with ecological and land use histories. Results indicate that the Balch plot, more closely located to the urban center, has different stand composition, condition, and vegetation growth rates, compared to the more rural Miller site. This study supports findings from a study done by Broshot in 2009, where more urban plots demonstrate a different stand composition and recruitment pattern than rural sites. The study is an initial step for exploring questions regarding the ecological status of Forest Park and how land use and disturbance, past and present, shape Portland's forested reserve.

Accurate estimation of Net Primary Productivity (NPP), which is a key component of the terrestrial carbon cycle, is very important in studies of global climate. Ecosystem models have been used for NPP estimates. Determining how much each source of uncertainty contributes to modeled NPP is veiy important before ecosystem models can be used with confidence over larger areas and time periods. This research has systematically evaluated the boreal ecosystem productivity simulator (BEPS) carbon model in mountainous terrain, Kananaskis, Alberta. After parameterization of the model, sensitivity analysis was conducted as a controlled series of experiments involving sensitivity simulations with BEPS by changing a model input value in separate model runs. The results showed that NPP was sensitive to most model inputs measured in the study area, but that the most important input variables for BEPS were LAI and forest species. In addition, the NPP uncertainty resulting from topographic influence was approximately 3.5 %, which is equivalent to 140 kg C ha"1 yr"1. This suggested that topographic correction for the model inputs was also important for accurate NPP estimation. Using the topographically corrected data, the carbon dynamics were simulated, and average annual NPP production by forests in Kananaskis was estimated at 4.01 T ha"1 in 2003.
xix, 117 leaves : col. ill. ; 29 cm.

The biochemical composition of conifer foliage in the Greater Victoria Watershed District (GVWD), Vancouver Island, Canada, was examined using hyperspectral remote sensing data. Imagery acquired from the airborne sensor Advanced Visible/Infrared Imaging Spectrometer (AVIRIS) was compared to sampled foliar chemical measurements to provide regional maps of biochemical distribution. The biochemical concentrations of nitrogen, chlorophyll and moisture derived from AVIRIS data were analyzed to provide an analysis of the forest canopy, comprised predominantly of Douglas-fir. The AVIRIS data were preprocessed to correct for atmospheric and geometric distortion, degradation, and noise inherent in the data in order to properly represent the forest canopy at the time of image acquisition. The AVIRIS data were used to investigate the relationship between the reflectance, absorbance and derivative values present in the imagery corresponding to the sampled chemical data. A total of 29 plots were used in a partial least squares regression analysis to analyze the relationship between the data sets to extract chemical constituents in the forest canopy. Nitrogen and total chlorophyll models have r2 values of 0.73 and 0.68 respectively. Due to the complexity of moisture interaction with hyperspectral data, regression models were unable to be computed for the AVIRIS data over the GVWD. Regression models were then applied to the entire AVIRIS dataset for regional mapping of the canopy biochemistry. The distribution of nitrogen and total chlorophyll in the forested areas of the GVWD was mapped.

Indigenous forests all over the world are suffering habitat alteration, loss of original extensions, and increase of isolation levels, affecting their existence and sustainability. In New Zealand about 70% of the original forest cover has been destroyed since human settlement, converting them to a rare and threatened resource. Part of the problem is because native forests are often immersed in a landscape where other land uses are competing for the same space. Effective conservation management of these indigenous forest remnants requires information about their vulnerability to threats, in space and time. Few studies provide an integrated assessment of the extent to which socio- economic effects are responsible for native vegetation vulnerability and how these relationships change through time. In this study socio-economic drivers at different scales are related to land cover changes. To analyse vulnerability of indigenous forests a temporal dataset was developed from aerial photography for the years 1942, 1961, 1984, and satellite images for the years 1999 and 2006. They were managed within a GIS, recording the extent and distribution of these forests and other principal land covers in a study area of ca. 80,000 ha in the Northland region. Information about incentives to land production and to conservation was compared to changes of composition, configuration and conversion of land cover. Spatial conditioners of change, such as elevation, land use capability and land legal protection, were also assessed as possible constrainers of indigenous forest loss. Results showed that the incentives to land production had changed their significance for vulnerability of indigenous forests through time. These became conditioned by other land covers and incentives to conservation, and besides, indigenous forest was a quite stable cover where the physical characteristics of their location were unsuitable for land production. I concluded that at scale of decades, changes in area of indigenous forest were reversible; non- linear; driven by political, institutional and economic changes but that, biophysical characteristics of the landscape can preclude conversion. Such conclusions may help to set priorities for the long term protection and management of indigenous forests.

The objectives of the study were to examine the socio-economic impact of outsourcing on forest-dependent communities, to evaluate the current outsourcing management system in Mondi Forests, and to assess the financial impact (costs savings) of outsourcing on Mondi Forests: Natal Region in KwaZulu-Natal. Participatory Rural Appraisal exercises were used to assess the socio-economic impact of outsourcing on forest-dependent communities. A questionnaire was then used on a sample of Mondi Forests personnel to evaluate the current outsourcing management system in Mondi Forests. Finally, cash-flow trends were used to assess the financial impact (costs savings) of outsourcing on Mondi Forests, Natal Region. Activities that have been outsourced include transport, harvesting operations, silviculture operations, security services, mechanical services, training, payroll services and information systems. Results show that outsourcing has impacted negatively on the livelihoods of some of the forest-dependent communities sampled. The negative impacts are mainly associated with a reduction in hygiene services offered to these communities and an increase in unemployment in some of these villages. Forest-dependent communities perceive outsourcing as the cause of poor relationship between the rural communities, forest companies and contractors as well as being the cause of high unemployment rates. Mondi Forests' personnel perceive that outsourcing goes beyond costs savings to include redirecting scarce resources toward core business activities. Lower morale and insecurity among forest staff members and negative views of the forestry companies by rural communities, unions and government departments were perceived as the disadvantages of outsourcing. Uncertainty with regards to employment continuity and social problems (e.g. increased forest fires, poor relationship with local communities) were perceived as outsourcing risks. Results show that Mondi Forests has implemented a number of strategies in order to reduce some of these risks and disadvantages by giving preference to their ex-employees when offering contracts, by providing start-up capital to emerging black contractors, and by initiating community development programmes in order to uplift the standard of living of the forest-dependent communities. Mondi Forests' personnel suggested that forest management. accounting, conservation management, and human resources are the best candidates for future outsourcing, since most other forest organizations in the world are already outsourcing them successfully. Most of these activities are still kept in-house in Mondi Forests. Results also show that outsourcing can be used with other rationalization methods to save costs. This is because costs savings in Mondi Forests: Natal Region, since 1998 to 2001 were .not only due to outsourcing, but also to some other management decisions such as reduced fertilizer and pesticides use. The total costs savings were R14.5 million from 1998 to 2001. Results support the need to strengthen the current rural development programmes in Mondi Forests, and to the establish Community Liaison Forums to improve communication with rural communities and to start community development programmes. A contractor upliftment programme was also recommended for developing the emerging black contractors. Lastly, company/contractor agreements must be reviewed in order to ensure that social responsibility aspects are appropriately managed. Outsourcing relationships need to consider the economic, environmental and social effects in order to be sustainable.
Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 2001.

Plantation forestry involves the management of man-made industrial forests for the purpose of producing raw materials for the pulp and paper, saw milling and other related wood products industries. Management of these forests is based on the cycle of planting, tending and felling of forest stands such that a sustainable operation is maintained. The monitoring and reporting of these forestry operations is critical to the successful management of the forestry industry. The aim of this study was to test whether the forestry operations of clear-felling, re-establishment and weed control could be qualitatively and quantitatively monitored through the application of classification and change detection techniques to multi-temporal medium (15-30 m) and a combination of textural analysis and change detection techniques on high resolution (0.6-2.4 m) satellite imagery. For the medium resolution imagery, four Landsat 7 multi-spectral images covering the period from March 2002 to April 2003 were obtained over the midlands of KwaZulu-Natal, South Africa, and a supervised classification, based on the Maximum Likelihood classifier, as well as two unsupervised classification routines were applied to each of these images. The supervised classification routine used 12 classes identified from ground-truthing data, while the unsupervised classification was done using 10 and 4 classes. NDVI was also calculated and used to estimate vegetation status. Three change detection techniques were applied to the unsupervised classification images, in order to determine where clear-felling, planting and weed control operations had occurred. An Assisted "Classified" Image change detection technique was applied to the Ten-Class Unsupervised Classification images, while an Assisted "Quantified Classified" change detection technique was applied to the Four-Class Unsupervised Classification images. An Image differencing technique was applied to the NDVI images. For the high resolution imagery, a series of QuickBird images of a plantation forestry site were used and a combination of textural analysis and change detection techniques was tested to quantify weed development in replanted forest stands less than 24 months old. This was achieved by doing an unsupervised classification on the multi-spectral bands, and an edge-enhancement on the panchromatic band. Both the resultant datasets were then vectorised, unioned and a matrix derived to determine areas of high weed. It was found that clear-felling operations could be identified with accuracy in excess of 95%. However, using medium resolution imagery, newly planted areas and the weed status of forest stands were not definitively identified as the spatial resolution was too coarse to separate weed growth from tree stands. Planted stands younger than one year tended to be classified in the same class as bare ground or ground covered with dead branches and leaves, even if weeds were present. Stands older than one year tended to be classified together in the same class as weedy stands, even where weeds were not present. The NDVI results indicated that further research into this aspect could provide more useful information regarding the identification of weed status in forest stands. Using the multi-spectral bands of the high resolution imagery it was possible to identify areas of strong vegetation, while crop rows were identifiable on the panchromatic band. By combining these two attributes, areas of high weed growth could be identified. By applying a post-classification change detection technique on the high weed growth classes, it was possible to identify and quantify areas of weed increase or decrease between consecutive images. A theoretical canopy model was also derived to test whether it could identify thresholds from which weed infestations could be determined. The conclusions of this study indicated that medium resolution imagery was successful in accurately identifying clear-felled stands, but the high resolution imagery was required to identify replanted stands, and the weed status of those stands. However, in addition to identifying the status of these stands, it was also possible to quantify the level of weed infestation. Only wattle (Acacia mearnsii) stands were tested in this manner but it was recommended that in addition to applying these procedures to wattle stands, they also are tested in Eucalyptus and Pinus stands. The combination of textural analysis on the panchromatic band and classification of multi-spectral bands was found to be a suitable process to achieve the aims of this study, and as such were recommended as standard procedures that could be applied in an operational plantation forest monitoring environment.
Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

Assessment of forest structural attributes has major implications in the management of forestry by providing information of ecological and economic importance. The traditional methods of assessment involve collecting data in the field and are regarded as labour-intensive and expensive. In plantation forestry, field campaigns are generally time consuming and costly, and may compromise profit maximisation. The introduction of lidar (light detection and ranging) remote sensing in forestry has shown promise to add value to the traditional field inventories mainly through large spatial coverages in a timely and cost-effective manner. Lidar remote sensing is an advanced system capable of acquiring information in both the vertical and horizontal dimensions at relatively high resolutions. Numerous studies have established that these qualities of lidar data are suited to estimating forest structural attributes at acceptably high accuracies. The generic approach in most studies is to use lidar data in combination with field data. Such an approach still warrants a high cost of inventory. It is therefore useful to explore alternative methods that rely primarily on lidar data by reducing the necessity for field-derived information. The aim of this study was to derive structural attributes of even-aged Eucalyptus grandis forest plantations using lidar data. The attributes are of significance to timber resource assessments and include plot-level tree height attributes, stems per hectare (SPHA), and volume. The surveyed field data included tree counting and measurement of tree height and diameter at breast height for sample plots. Volume was then calculated using standard allometric models. Small-footprint lidar data of the plantations were also acquired coincident with the field inventories. Mean tree height and dominant height were estimated at a range of simulated lidar point densities between 0.25 points/m2–6 points/m2. Various plot-level distributional metrics were extracted from height values of lidar non-ground points and related with field mean and dominant height values using stepwise regression analysis. The results showed that both attributes could be estimated at high accuracies with no significant differences arising from variations in lidar point density. Estimation of SPHA relied on the exploration of semi-variogram range as a mean window size for applying local maxima filtering to the lidar canopy height surface. A comparative approach of window size determination used pre-determined within-row tree spacing, based on planting information. Two secondary objectives were addressed: comparing spatial resolutions of canopy height surfaces interpolated from non-ground height values and comparison of lidar point densities simulated at three levels. Comparison of spatial resolutions of canopy height surfaces were performed at 0.2 m, 0.5 m, and 1 m using a lidar point density of 5 points/m2. The results indicated that 0.2 m is the most appropriate resolution for locating trees and consequently deriving SPHA. Canopy height surfaces of 0.2 m resolution were created at simulated densities of 1 point/m2, 3 points/m2, and 5 points/m2. While all estimates were negatively biased relative to field-observed SPHA, lidar densities of 3 points/m2 and 5 points/m2 returned similar accuracies, which were both superior to 1 point/m2. It was concluded that 3 points/m2 was sufficient to achieve the accuracy level obtained from higher lidar point densities. Plot-level mean height, dominant height, and volume of trees were estimated for trees located using local maxima filtering approaches at the three lidar point densities. Mean height and dominant height were both estimated at high accuracies for all local maxima filtering techniques and lidar point densities. The results were also comparable to the approach that employed regression analysis that related lidar-derived distributional metrics and field measurements. Estimated dominant height and SPHA, as well as age of trees, were used as independent variables in a function to estimate plot-level basal area. The basal area was then used to compute diameter of the tree with mean basal area, referred to as quadratic mean diameter at breast height (QDBH). Mean tree height and QDBH were used as independent variables in a standard equation to calculate mean tree volume, which was then scaled up to the plot-level. All estimates for the local maxima filtering approaches and lidar point densities returned negatively biased volume, when compared to field observations. This was due to the underestimation of SPHA, which was used as a conversion factor in scaling up from tree-level to plot-level. Volume estimates across lidar point densities exhibited similarities. This suggests that low lidar point densities (e.g., 1 point/m2) have potential for accurate volume estimation. It was concluded that multiple forest structural attributes can be assessed using lidar data only. The accuracy of height derivation meets the standards set by field inventories. The underestimation of SPHA may be comparable to other studies that applied different methods. However, improved estimation accuracy is needed in order to apply the approaches to commercial forestry scenarios. The significance of improving SPHA estimation extends to improved volume estimation. In addition, the potential improvement should also take into consideration the density of lidar points, as this will impact on the cost of acquisition. This research has taken a significant step towards determining if lidar data can be used as a stand-alone remote sensing data source for assessment of structural plantation parameters. Not only does such an approach seem viable, but the lower required point densities will help to reduce acquisition costs significantly.
Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

Environmental degradation and soil erosion begins when production forests are harvested. Unfortunately, logging cannot be avoided in plantation forests and since this operation can render the land more susceptible to erosion, any negative impacts need to be addressed properly. Erosion potential is predicted by evaluating the response of land cover, soil and slope to the impact of rainfall and human activities. The role of remote sensing and geographical information systems (GIS) in erosion prediction is to collect information from images and maps; combine and analyse these data so that it is possible to predict the erosion risk. The objective of this study was to produce a method to identify areas most susceptible to erosion and predict erosion risk. It is intended that the method be used particularly by forestry planners and decision makers so that they can improve forest management, especially during logging. The study area was within Kebumen and Banjarnegara districts of Central Java, Indonesia. Imagery used included a Landsat 7 satellite image (28th April 2001) and panchromatic aerial photos (5th July 1993). Other data was derived from topographical, soil, and geological maps, and 10 years of daily rainfall data from 17 rainfall stations. Predicting erosion in this study was done by combining rainfall, slope, geology, and land cover data. The erosion risk was predicted using land cover and soil type and depth. A rainfall map was generated using a thin plate spline method. A slope map was derived from a DEM which was generated by digitizing contours and spot heights from topographic maps. A geological map was derived from Landsat image classification with assistance from a 1:100000 scale geological map; and a land cover map was produced from an interpretation of the Landsat image and aerial photographs. A stratified classification technique was used to delineate land covers in the study area with an accuracy of 44%. The low accuracy could be attributed to the complexity of the area and the temporal variation in the data acquisition. The analysis of erosion risk showed that mixed forests and monotype forest experienced high and moderately high erosion risk. This condition supported the contention that harvest plans must incorporate soil conservation measures.

A study was undertaken to compare growth potential of three Eucalyptus species of natural origin in South Eastern Australia, with commercially grown species on mid and high altitude temperate sites in the summer rainfall growing zones in South Africa. The three species were Eucalyptus globulus subsp. bicostata (E. bicostata), Eucalyptus cypellocarpa and Eucalyptus nobilis. Nine sites were selected to represent the growing areas of South Africa experiencing cold winter drought with occasional snow falls. Improved, commercially grown pure Eucalyptus species and interspecific hybrid clones were included as controls in the trials to give comparative growth performances on specific sites. Both balanced and unbalanced lattice designs were used to evaluate the growth potential of the unimproved Australian species and the improved commercial controls incorporated into the trials. Volume production and basal area growth were assessed for the three species at all sites. However, only three sub species E.globulus (E. bicostata, E. maidenii and E. globulus) showed varying levels of disease (Mychosphaerella nobilosa) infestation and this was therefore assessed in trials at 12 and 30 months respectively, and correlation analysis was used to study the relationship between the impact of disease infestation and growth performance. It was found that negative phenotypic correlations existed between the levels of infection and tree growth. ie greater infection slower growth. Evaluation of genotype x environment interaction (GXE) revealed that this did not exist in the E. bicostata nor E. nobilis populations, and therefore one population of each species can be developed for all the sites tested. E. cypellocarpa was the only species that showed some GXE interaction implying that separate populations to be developed for different sites. Contrary to what was expected, unimproved Eucalyptus species being investigated performed equally as well as the improved commercial species included as controls, thus providing potential for commercial deployment with selection and breeding.
Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.