350 research outputs found
The impact of oil palm expansion on environmental change: putting conservation research in context
No full textNon
The Last Prospectors
No full textby John Merwin, D Magazine, July 1976. Stories of several early oil prospectors in Oklahoma and Texas. Mentioned are: E. H. R. Sabens, Leland Fikes, Will McFadden, Ernest W. Marland, Harry Ratliff, Columbus Marion "Dad" Joiner, Waco Turner, Pete Burton, Jake Hamon,Titanic Thompson and H. L. Hunt. The Carlton and Blackstone Hotels in Tyler are also mentioned. 8 pages, original, published material; gift-Jean Neustadt, 11/16/7
Poiesis and Obstruction in Art Practice
No full textThis PhD thesis examines the concept of poiesis, that is ‘calling into existence that which was not there before’, in the context of obstruction in studio practice. It poses the question ‘Is there a methodology that engages with obstruction which in turn calls new work’? In this thesis, the concept of poiesis emerging from the late Dr. Murray Cox’s ‘Aeolian Mode’, is analyzed alongside a concept of praxis, (a philosophical companion to poiesis), familiar to artistic practice. This thesis describes the orientation of the original idea, The Aeolian Mode, clinically developed by Dr. Murray Cox in Broadmoor Psychiatric Hospital. This PhD seeks to identify if there are similar ‘tenets of approach’ held within the methodology of ‘The Aeolian Mode’, that would be useful or are identifiable in artistic studio practice. This thesis draws on the work of the philosopher, Professor Richard Kearney, specifically Kearney’s ideas on the necessity of ‘the other’ for ‘radical possibility’ to occur. It maps a context of both Freudian and Jungian interpretations of art practice, identifying how these ideas have shaped the way art is seen today. Furthermore, it challenges the Freudian idea of ‘pathography’ and favours a Jungian approach of ‘individuation’ in the understanding of creative processes. It develops a ‘methodology of the conversation’, interviewing students, established artists, tutors about their approaches to obstruction/poiesis in art practice. Additionally, it examines my own obstruction to painting and identifies the methodology that released me from this obstruction. Conducting these interviews on art practice has enabled me to confirm my initial concerns about Freudian ‘pathography’ whilst validating the possibility of the Jungian concept of ‘individuation’ being of use to art practice. Finally, this PhD discusses the implications for further study and research, which have emerged during the ‘methodology of the conversation’ and the task of dissolving my obstruction to painting
Old Bulloch Personalities
No full textThe sixth issue of Southern Folkways Journal Review contains poems handed down by three different Bulloch County families, a paper on the Salzburgers, an interview with Daisy Trapnell, an article on Bulloch County personality “Bitin’ Jake,” a letter concerning Isaac Chadburn Daniel, a query concerning the lives of John and Robert Dunwoody, and four sketches by Rita Turner Wall.https://digitalcommons.georgiasouthern.edu/bchs-pubs/1027/thumbnail.jp
Spiders in canopy and ground microhabitats are robust to changes in understory vegetation management practices in mature oil palm plantations (Riau, Indonesia)
No full textConversion of natural habitats to oil palm agriculture has caused declines in biodiversity and changes in ecosystem functions. To preserve biodiversity we must protect natural habitats, but once oil palm plantations are established, developing more-environmentally friendly management strategies could support higher levels of within-plantation biodiversity and boost the delivery of ecosystem services, possibly increasing oil palm productivity. In this study, we use a before-after control-impact (BACI) experiment to test whether three understory vegetation management strategies affect spider abundance, species richness, and species-level community composition in canopy and ground microhabitats in mature oil palm plantations. Our treatments encompassed the range of current management practices and included heavy applications of herbicides to eliminate all understory vegetation, maintaining some understory vegetation using business-as-usual herbicide applications, and enhancing understory vegetation by not applying any herbicides. We focussed on spiders, as they are both biologically and economically important in oil palm plantations, owing to their important pest control services. We identified more than 1000 spiders, representing 20 families and 83 morphospecies. The treatments did not affect any aspects of spider biodiversity, although the abundance and species richness of canopy-dwelling spiders changed between pre- and post-treatment sample periods, independent of treatment. Our findings indicate that differences in understory vegetation management practices do not affect spiders, or the pest management services that they provide, in mature oil palm plantations. As such, more extreme changes in management would probably be required to enhance spider biodiversity in oil palm plantations in the long-term. Further studies are needed to determine the practicalities of such approaches, to assess how changes in vegetation management practices affect spiders in additional microhabitats, and how the impacts of such approaches vary across the 20–30 year oil palm commercial life cycle
Removing understory vegetation in oil palm agroforestry reduces ground-foraging ant abundance but not species richness
No full textAnts are known to provide valuable ecosystem services in agricultural landscapes, including oil palm plantations. Their communities are less diverse and more uneven in oil palm compared with forest, and this may increase their vulnerability to disturbance. This study quantifies ant communities in oil palm agroforestry and experimentally tests their robustness to a common-practice high-disturbance management intervention: removing understory vegetation.
Fieldwork was based at the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Understory Vegetation Project in Sumatra, Indonesia, where three treatments varying in their degree of understory vegetation management were established in 2014: (1) widespread herbicide was applied removing all understory vegetation (Reduced); (2) herbicide was applied to the harvesting paths and circles, and other vegetation was allowed to grow (Normal – control); (3) no herbicide was applied (Enhanced). We measured ground-foraging ant communities before and after the treatments were implemented, using pitfall traps over 324 trap-nights (a trap-night is one trap set for one night). We investigated how ant abundance, species richness, species evenness, beta diversity, and community composition differed between the treatments.
We found 3507 ants across 68 species or morphospecies. Seven of these were highly abundant and accounted for 78% of individuals. Post-treatment ant abundance was lower in the reduced treatment (mean per plot: 84) than in the normal (159) and enhanced (131) treatments, which did not differ from each other. Species richness, species evenness, beta diversity and community composition were not affected by the vegetation treatments.
We recommend that oil palm growers maintain understory vegetation in oil palm plantations to support ground-foraging ants. Though not tested here, this may also improve ant-mediated ecosystem services, such as pest control, seed dispersal, nutrient redistribution, and the maintenance of soil health. This study demonstrates that enhancing habitat complexity through management practices can support biodiversity in monocrop landscapes.
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A large-scale forest fragmentation experiment: the stability of altered forest ecosystems project
No full textOpportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecol- ogists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification
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Removing understory vegetation in oil palm agroforestry reduces ground-foraging ant abundance but not species richness
No full textAnts are known to provide valuable ecosystem services in agricultural landscapes, including oil palm plantations. Their communities are less diverse and more uneven in oil palm compared with forest, and this may increase their vulnerability to disturbance. This study quantifies ant communities in oil palm agroforestry and experimentally tests their robustness to a common-practice high-disturbance management intervention: removing understory vegetation.
Fieldwork was based at the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Understory Vegetation Project in Sumatra, Indonesia, where three treatments varying in their degree of understory vegetation management were established in 2014: (1) widespread herbicide was applied removing all understory vegetation (Reduced); (2) herbicide was applied to the harvesting paths and circles, and other vegetation was allowed to grow (Normal - control); (3) no herbicide was applied (Enhanced). We measured ground-foraging ant communities before and after the treatments were implemented, using pitfall traps over 324 trap-nights (a trap-night is one trap set for one night). We investigated how ant abundance, species richness, species evenness, beta diversity, and community composition differed between the treatments.
We found 3507 ants across 68 species or morphospecies. Seven of these were highly abundant and accounted for 78% of individuals. Post-treatment ant abundance was lower in the reduced treatment (mean per plot: 84) than in the normal (159) and enhanced (131) treatments, which did not differ from each other. Species richness, species evenness, beta diversity and community composition were not affected by the vegetation treatments.
We recommend that oil palm growers maintain understory vegetation in oil palm plantations to support ground-foraging ants. Though not tested here, this may also improve ant-mediated ecosystem services, such as pest control, seed dispersal, nutrient redistribution, and the maintenance of soil health. This study demonstrates that enhancing habitat complexity through management practices can support biodiversity in monocrop landscapes
A Compositional Approach to Certifying Almost Global Asymptotic Stability of Cascade Systems
No full textIn this letter, we give sufficient conditions for the almost global asymptotic stability of a cascade in which the subsystems are only almost globally asymptotically stable. The result is extended to upper triangular systems of arbitrary size. In particular, if the unforced subsystems are almost globally asymptotically stable and their only chain recurrent points are hyperbolic equilibria, then the boundedness of forward trajectories is sufficient for the almost global asymptotic stability of the full upper triangular system. We show that unboundedness of such cascades is prohibited by growth rate conditions on the interconnection term and a Lyapunov function for the unforced outer subsystem, and the required structure for the chain recurrent set is enjoyed by classes of systems common in geometric control, e.g., dissipative mechanical systems. Our results stand in contrast to prior works that require either time scale separation, strong disturbance robustness properties, or global asymptotic stability in the subsystems.This work was supported in part by Qualcomm Research; in part by NSF under Grant CCR-2112665; and in part by the NSF Graduate Research Fellowship Program. Recommended by Senior Editor L. Menini. (Corresponding author: Jake Welde.)https://ieeexplore.ieee.org/document/1014637
Establishing the evidence base for maintaining biodiversity and ecosystem function in the oil palm landscapes of South East Asia
No full textThe conversion of natural forest to oil palm plantation is a major current threat to the conservation of biodiversity in South East Asia. Most animal taxa decrease in both species richness and abundance on conversion of forest to oil palm, and there is usually a severe loss of forest species. The extent of loss varies significantly across both different taxa and different microhabitats within the oil palm habitat. The principal driver of this loss in diversity is probably the biological and physical simplification of the habitat, but there is little direct evidence for this. The conservation of forest species requires the preservation of large reserves of intact forest, but we must not lose sight of the importance of conserving biodiversity and ecosystem processes within the oil palm habitat itself. We urgently need to carry out research that will establish whether maintaining diversity supports economically and ecologically important processes. There is some evidence that both landscape and local complexity can have positive impacts on biodiversity in the oil palm habitat. By intelligent manipulation of habitat complexity, it could be possible to enhance not only the number of species that can live in oil palm plantations but also their contribution to the healthy functioning of this exceptionally important and widespread landscape
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