1,721,122 research outputs found
Evaluating protected area effectiveness using bird lists in the Australian Wet Tropics
Full text linkAimProtected areas underpin many global conservation efforts. However, it is often unclear whether they are effective in maintaining their biodiversity values, both absolutely, and also relative to other conservation actions or land uses. Longitudinal population data are critical for determining protected area performance robustly, but such data are rare. As such, there is often insufficient information with which to make adequate, informed decisions for policy and management. Conversely, informally collected data, such as species lists, are common, especially for birds, and they are often the only source of historical data. The aim of this study was to use list data to evaluate the contribution of protected areas to the conservation of endemic birds
Balancing agricultural and ecological needs : biodiversity, land use and ecosystem services in the Koedoes River Catchment, Limpopo.
No full textM. Sc. University of KwaZulu-Natal, Pietermaritzburg 2015.A major topic in natural science research is land degradation and unwise land use resulting in
biodiversity loss and impact negatively on ecosystem functioning. In addition, an increasing
human population trend leads to food security concerns. Some commercial farmers are ideally
placed on the interface between agricultural and natural systems to investigate these issues. In
this thesis we investigate the quaternary catchment-scale biodiversity, land-use patterns and
interactions between conservation, restoration and agricultural activities in an agriculturally
productive valley. The 40,000ha Koedoes River Catchment in Limpopo Province produces
high numbers of tomatoes, avocados and mangoes. Most of this catchment is managed by
ZZ2, a farming conglomerate that practice an environmentally sensitive approach to
commercial farming. In the first two chapters a fine-scale vegetation map is created for the
catchment, accompanied by detailed descriptions of the eleven mapped vegetation units. Over
a 1300m altitudinal range, three biomes, 49 red-listed plant species, fifteen protected tree
species and more than 500 species of vascular plant are represented in the catchment. In a
subsequent chapter, the catchment-wide land-use patterns were mapped and related to
vegetation patterns. The most expansive vegetation type appears to be one of the most
threatened because large areas have been converted to croplands, while one of the most biodiverse
vegetation units is severely threatened by degradation and invasive plants. Using this
information, in addition to stakeholder feedback regarding the relative supply and demand for
ecosystem services, a map of high priority biodiversity, ecosystem services and agricultural
use areas was created to serve as a strategic management tool for stakeholders and land
managers. In the final chapter the fine-scale effects of land use practices on biodiversity and
ecosystem functioning are investigated. Using invertebrate community data from three
adjacent headwater sub-catchments, invertebrate diversity and downstream biological water
quality (measured by SASS5) was related to upstream land use. Ultimately, this thesis serves
to illustrate some of the complex interactions and inter-dependencies between conservation
and agriculture, and to offer evidence for mutually beneficial synergies between both these
important sectors
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The impact of land degradation on landscape function in Mount Fletcher, Eastern Cape.
Full text linkMaster of Science in Environmental Science. University of KwaZulu-Natal, Pietermaritzburg 2016.The severity of natural vegetation degradation has become a serious challenge, causing negative impacts on the vegetation ecosystems, livestock population, and productivity, landscape organization and river systems. The research project focussed on the impact of land degradation on the landscape function and vegetation cover. The study was addressing two main aims. The first aim was to assess the landscape function analysis (LFA) method as a tool to determine the landscape functioning and differentiate the condition of the rangeland into various levels of degradation caused by over-grazing. The second aim was to determine the effects of excluding grazing herbivores using on ecosystem functioning.
Monitoring is an important part of the restoration process, it allows restoration practitioners to assess success and to adapt management strategies and restoration methods, so as to evaluate change in their restoration objectives. The landscape function analysis method was applied in this study. The LFA method is a field based technique that examines the landscape level of ecosystem function and determines the functional status of rangelands. The LFA consists landscape organization and soil surface assessment indices which reflect the ability of the landscape to capture and retain resources. Data were collected inside and outside of the exclosure plots to determine whether there were differences in some measured parameters (landscape organization index, total patch area, number of patches/10 m, average inter-patch length, stability, infiltration and nutrient cycling) between the non-grazed (exclosure) and continuously grazed area.
The vegetation cover from the exclosure plots was more improved as well as landscape functioning. These results demonstrated that grazing exclusion is an effective measure for maintaining the landscape functioning and improving above ground cover. The adoption of livestock exclusion practice had a profound impact on vegetation recovery and in turn on litter accumulation and improvement of soil fertility. The landscape organization indices and the soil surface assessment (SSA) indices played the most important roles in contributing to the knowledge of the landscape functioning. The study found that LFA method can be used as a tool to detect the landscape functioning and differentiate between intact and degraded areas
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Land use and its impact on the Succulent Karoo
No full textThe Succulent Karoo biome (SK biome) is one of the 25 internationally recognized biodiversity hotspots in South Africa with approximately 1940 endemic species. The SK biome is, however, poorly conserved with less than 5% of the area under formal protection. It is also highly threatened by a range of different land use practices. Considering the lack of protected areas and the high levels of endemism (about 40%), which characterize the region, the current and future land use practices are likely to be the key factors in determining the future conservation of the area. Understanding the land use pattern and its drivers that have occurred in the SK biome provides a useful starting point for outlining the future research needs and establishing conservation goals. This project investigates a range of different land use practices such as urban settlement, mining, cropland, conservation and livestock production with their associated environmental drivers. The study used a Geographical Information System (GIS) to map the current extent of land use practices based on available data from different sources in the SK biome. The study also mapped the current extent of livestock density in two land tenure systems (private and communal) of Namaqualand and developed a statistical model to assess the future agricultural potential in the SK biome. The current status of the land use practices in the SK biome shows that most of its area is used for extensive grazing (90%) followed by conservation (4.8%). Due to the aridity of the area, agriculture potential is low. The results confirmed that the conservation status of the SK biome is relatively low but improving, with 4.8% of the biome conserved. Only 3.5%, however, is formally protected in statutory reserves. The remaining conserved area (1.3%) is conserved in non-statutory reserves
The conservation value of abandoned croplands in Mpumalanga’s grasslands
Full text linkDissertation (MSc)--University of Pretoria, 2014.The South African grassland biome is one of the most transformed and least protected biomes in the country. The conservation of this species-rich biome is further complicated by the occurrence of abandoned croplands in areas classified as ‘natural’. In fact, more than 10 % of the areas classified as natural in Mpumalanga are abandoned croplands. Although it is recognized that they differ from pristine grasslands in species richness and diversity, few studies have assessed the value of abandoned croplands for conservation. The aim of this study was to determine the value of abandoned croplands for conservation in Mpumalanga’s grasslands in terms of species composition and landscape connectivity. In the first part of the study the species composition of abandoned croplands was compared to that of pristine natural grassland in the Nooitgedacht Dam Nature Reserve in Mpumalanga. In the second part of the study the contribution of abandoned croplands to overall landscape connectivity in the grassland biome of Mpumalanga was evaluated. It was found that there is a significant difference in species composition, especially for resprouting forb species, between abandoned croplands and pristine natural grasslands. There were also a significant difference in total species richness and forb species richness, while alien plant species richness was significantly higher in abandoned cropland plots. There was no significant difference in medicinal plant species richness. It could be seen that, although different to pristine natural grasslands, the vegetation on these abandoned croplands was not degraded, and can be valuable providers of ecosystem services such as medicinal plants and thatching grass, and can also serve as habitat for different species. It was found that the pristine natural grassland patches in Mpumalanga are already relatively well connected and that abandoned croplands further improved the overall landscape connectivity of grassland habitat patches by 33 %. The results indicated that abandoned croplands have a definite value for conservation by contributing to species richness and connecting the landscape.lk2014Plant ScienceMScUnrestricte
An assessment of fire regimes on different vegetation types using MODIS burned area products.
Full text linkMaster of Science in Geography. University of KwaZulu-Natal, Pietermaritzburg 2017.Cost-efficient satellite data has been widely used to map the spatial and temporal distribution of fires in resource scarce regions such as southern Africa. However, the accuracy of such data is often unknown, which compromises the integrity of the mapped burnt areas. In that regard, there is need to validate the accuracy of these data products if they are to be used for drawing strategies for monitoring and managing natural resources such as grasslands. This study, therefore, evaluated the mapping accuracy of the cost-free MODIS burned area satellite data products for 2013 and 2014 burning seasons in the grasslands of KwaZulu-Natal, South Africa. To validate MODIS data, we used independent reference data derived from the new generation Landsat 8 Operational Land Imager (OLI) based on the new accuracy assessment procedure promulgated. A total of 60 ground sampling sites were used in this study in conjunction with Landsat 8 data to validate MODIS burned area products. Results of this study illustrate a high level of agreement (>80% overall accuracy) between the MODIS burned area products and the independent reference data. Meanwhile, Landsat data was also validated by ground collected points yielding an accuracy of 94%. Specifically, MODIS data was validated by ground collected points yielding an accuracy of 87%. These findings suggest that MODIS burned area products (MCD45A1) are an accurate, reliable and cheap data source for mapping burnt areas at a regional scale
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