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Molecular analysis of guano from bats in bat houses on organic pecan orchardsBrown, Veronica Angelelli 01 May 2010 (has links)
Bats are generalist predators of night flying insects, including many crop pests. Pecan nut casebearer (Acrobasis nuxvorella), hickory shuckworm (Cydia caryana), and several stink bug species are some of the most damaging crop pests in pecan orchards. Attracting bats to agricultural areas using bats houses may reduce the numbers of these pests and, consequently, their economic impact. This study uses quantitative polymerase chain reaction (QPCR) of mitochondrial DNA found in the guano of bats living in bat houses on organic pecan orchards to document the consumption of pecan nut casebearer, hickory shuckworm, and corn earworm (Helicoverpa zea), which is one of the most destructive pests of many crops throughout the world. This study also uses direct sequencing of insect remains in bat fecal pellets to identify species of stink bugs consumed by bats in bat houses. Evidence that bats prey upon crop pests supports the hypothesis that bats are both economically and ecologically beneficial to pecan farmers and provides incentives for bat conservation.
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Simulation Modeling of a Tropical Cave EcosystemCotter, Hannah B 01 January 2015 (has links)
The Tamana Cave system in Trinidad is relatively unaffected by the environment outside of the cave walls, like most cave ecosystems. Since a very limited amount of light can enter the cave, bat movement controls the temperature cycle rather than the solar radiation that controls it in the surrounding forest. Similarly, the ecosystem cannot be sustained by energy from photosynthesis and so the main source of energy comes from the guano produced by the insectivorous bat species, N. tumidirostris. The frugivorous bat species, P. hastatus, also roosts inside of the cave, but the wetness of the top level of its guano prevents the guano from being suitable for cockroach consumption and therefore ends the flow of energy through the system. STELLA software was used to create a model consisting of three stacked logistic growth equations that demonstrate the ecosystem of Tamana cave. The model focuses on the population of insectivorous bats, on the guano that this species produces, and on the cockroach species, E. distanti. The model provides insight into the population dynamics and environmental processes at play in the cave, and is useful in predicting the behavior of the ecosystem. After running the model under a number of different scenarios, the graphs were used to visually display the effects of altering inputs in the system. These altered inputs represent hypothetical changes that could occur in a natural system such as a lowered intrinsic rate of increase bat population, an increase in initial bat population, or a decrease in the amount of guano that each cockroach needs to survive.
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The influence of seabird-derived nutrients on island ecosystems in the oligotrophic marine waters of south-western AustraliaHarrison, Sofie Alice. January 2006 (has links)
Thesis (M.Sc.)--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.
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Remote sensing of penguin populations : development and application of a satellite-based methodBrown, Jennifer Anne January 2018 (has links)
Five penguin species breed in Antarctica: emperors, Adélies, chinstraps, gentoos and macaronis. These are important Antarctic mid-trophic level predators and under predicted climate change are believed threatened. Accurate monitoring of populations is therefore of growing importance owing to the changing environment in which they live, particularly on the Western Antarctic Peninsula where rapid warming is occurring. The inaccessibility and size of many colonies makes ground based monitoring difficult with remote sensing providing an alternative, relatively low cost, monitoring method. Advancing current monitoring methods will help improve estimates of population trajectories at a regional scale. Recent and future progress in remote sensing, with new satellite sensors and platforms, offers increased potential for accurate, consistent large-scale data collection. The work in this thesis focuses on difficult to monitor brush-tailed penguins (Adélies, chinstraps and gentoos), aiming to develop new techniques and algorithms to improve their monitoring by satellite imagery. Penguin detection in satellite imagery is based on the red/brown guano stains that colonies create, with these stains evident from space. Fieldwork undertaken in Antarctica (Nov 2014-Jan 2015) using a field spectroradiometer obtained the first in situ hyperspectral reflectance spectra of Adélie and chinstrap guano. These spectra are used to identify the features responsible for varying guano types and suggest new indices for differentiating these in satellite imagery. Satellite imagery coincident with the fieldwork, obtained from WorldView-3 (~40 cm resolution) and Landsat 8 (~15 m resolution), are used to trial the index derived from the field spectra. Analysis of the field data and satellite images includes examination of guano colour for different species and comparison of methods of guano detection, aiming to enhance species detection from satellite imagery. In addition, Landsat 8 imagery from further locations is used to produce time series of this index for colonies, examining how guano colour changes over the breeding season are seen in satellite imagery. This dissertation concludes with recommendations for future developments of satellite-based methods based on the results of these analyses. Such improvements should help improve our current understanding of penguin population and continuing population changes in relation to climate change.
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Molecular analysis of guano from bats in bat houses on organic pecan orchardsBrown, Veronica Angelelli, January 2010 (has links)
Thesis (M.S.)--University of Tennessee, Knoxville, 2010. / Title from title page screen (viewed on July 20, 2010). Thesis advisor: Gary McCracken. Vita. Includes bibliographical references.
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Agricultura química na Inglaterra e nos Estados Unidos no século XIX: alguns aspectos dos estudos e trabalhos sobre o guano / Chemical agriculture in England and the USA during the nineteenth century: some aspects of studies and works about guanoLima, Edson 11 September 2015 (has links)
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Previous issue date: 2015-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The studies on agriculture, both in England and the United States of America, have been essential for the institutionalization of the chemical agriculture in the nineteenth century. Those studies were centered on the cooperation between the researches developed in educational institutions and the ones developed in the work field. By that time, the increase of the soil fertility was a matter that needed to be solved in both countries and the Peruvian guano began to be broadly used, thus, originating uncountable studies involving its composition and efficiency as a fertilizer. This material accomplished great commercial value, leading to its counterfeiting in so many ways. Thereby, releases focusing on farmers, convincing them of the guano s efficiency as a fertilizer and also warning them about the counterfeits and how to recognize them, were published in the mid-nineteenth century. In this context, this present work approaches, especially, the texts from J.C. Nesbit (published in England) and from S. Robinson (published in the USA), which spread the using of guano as a solution for the soil infertility / Na Inglaterra e nos Estados Unidos do século XIX, os estudos em agricultura se mostraram essenciais para a institucionalização da agricultura química. Tais estudos estavam centrados na cooperação entre as pesquisas desenvolvidas nas instituições de ensino e as pesquisas realizadas no trabalho do campo. Naquele período, o aumento da fertilidade do solo era uma das questões a ser resolvida em ambos os países e o guano peruano passou a ser amplamente utilizado, fazendo originar inúmeros estudos envolvendo sua composição e eficiência como fertilizante. Esse material alcançou, ainda, grande valor comercial, levando à sua falsificação de diversas maneiras. Com isso, em meados do século XIX, surgem, tanto na Inglaterra como nos Estados Unidos publicações destinadas aos agricultores procurando, por um lado, convencer os leitores da eficiência do guano como fertilizante e, por outro, alertá-los sobre as falsificações assim como fornecer meios para reconhecer o produto adulterado. Neste contexto, esta dissertação aborda principalmente os textos de J.C. Nesbit (publicado na Inglaterra) e de S. Robinson (Estados Unidos), que promoviam a utilização do guano como solução para os problemas de infertilidade dos solos
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"Stinky and smelly - but profitable" : the Cape guano trade, c.1843 - 1910Snyders, Hendrik 12 1900 (has links)
Thesis (PhD)-- Stellenbosch University, 2011. / ENGLISH ABSTRACT: Soil infertility and concomitant low levels of food security under conditions of population pressure and land scarcity have been, and still remain, one of society’s most daunting challenges. Over time, societies have tried to maximize the yield from the available land through the use of various fertilisers. In the 19th century in the midst of an environment infertility crisis, guano (bird dung) from the Peruvian coastal islands became, through a combination of factors, the international fertilizer of choice for most commercial farmers. As a result, a combination of natural factors, monopoly control and price manipulation contributed to the relative scarcity of the product. Nevertheless, strategic manoeuvring between the major players prevented any significant change in the supply regime.
News of discoveries along the African coasts in the 1840s, some inside the territorial waters of the Cape Colony, introduced a new dimension to the trade. Both established merchant houses and new contenders strategised in an attempt to gain monopoly control. These events created new policy crises for the Cape Colony, the closest legal authority, and led to new policy and other initiatives in the absence of imperial precedents. The trade in guano also impacted on constitutional, political and scientific developments in the colony. Key amongst these was the struggle for monopoly control over both the Cape- and Ichaboe-based supply, which pitted individuals, family members and businesses against each other. The process became intertwined with political developments such as the transfer of political control from the Imperial authorities to the colonies. In addition, a coercive labour system developed under the colonial administration and colonial farmers struggled for fair access to the fertiliser, which added another dimension to the trade. / AFRIKAANSE OPSOMMING: Daar is ‘n noue verband tussen bevolkingsgetalle, oesopbrengs, voedselsekuriteiten die beskikbaarheid van voldoende bewerkbare landbougrond. Waar samelewings probleme ervaar met die gehalte van hul landbougrond, is daar heel dikwels ook lae vlakke van voedselsekuriteit en word daar gewoonlik ook ‘n onsekere van-die-hand-tot–die-mond bestaan gevoer. As ‘n teenvoeter vir hongersnood as gevolg van lae oesopbrengs, het uiteenlopende samelewings met verloop van tyd en na gelang van hulle natuurlike omstandighede, bepaalde bemestingstradisies ontwikkel in ‘n poging om ‘n volhoubare opbrengs te verseker.
Gedurende die 19de eeu, het ghwanobemesting te midde van ‘n wêreldwye grondgehalte krisis, ongekende gewildheid onder winsgedrewe landbouers bereik en voorts ook daarin geslaag om ander vorme van bemesting soos beenmeel en kraalmis as voorkeur produkte te vervang. As gevolg van ‘n kombinasie van natuurlike faktore, monopoliebeheer oor die eiland-gebaseerde ghwanobron en prysmanipulasie, was die produk wataanvanklik net vanaf Peru in Suid Amerika ingevoer is, dus nie vrylik beskikbaar nie en moes belangstellende boere hoë pryse daarvoor betaal. Vanselfsprekend het dit tot groot frustrasie en ontsteltenis in die geledere van diegene wat ‘n belegging in kommersiële landbou wou maak, gelei. Die onderlinge politieke intriges, knoeiery en pogings van plaaslike en oorsese sakemanne om mekaar te uitoorlê in die soeke na alleenbeheer oor die beskikbare ghwanobronne, het sake nie juis verbeter nie. Inteendeel, die situasie het net vererger toe alternatiewe ghwano bronne langs die wes- en ooskus van Afrika sowel as op ‘n reeks ander eilande in die Atlantiese Oseaan ontdek is.
Die ontdekking van ghwano binne die Kaapse gebeidswaters in die 19de eeu, het die owerhede met ’n beleidsdilemma waarvoor daar nie enige presedente in die Britse Ryk bestaan het nie gelaat. Daarbenewens was die kolonie te midde van heelparty konstitusionele en ander kwessies en het die toevoeging van die ghwanohandel die maatskaplike en politieke lewe van die kolonie wesenlik beïnvloed.
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Fungal Community Diversity and Structure from Cave Mineral Surfaces and Bat Guano in Kartchner Caverns, ArizonaVaughan, Michael Joe Steven January 2012 (has links)
Research regarding the distribution and structure of fungal communities in caves is lacking. The current study examines fungal communities in Kartchner Caverns, a mineralogically diverse cave located in the Whetstone Mountains, Arizona, USA. The first study examines culturable fungal diversity from speleothem surfaces. Twenty-one fungal genera represented by 43 genotypes and 53 distinct morphological taxonomic units (MTU) were recovered from 15 speleothems. Analysis of DGGE profiles indicated a significant effect of sampling site on community structure. The second study examined fungal diversity from speleothem and rock wall surfaces using the 454 FLX Titanium sequencing platform using the rDNA internal transcribed spacer 1 (ITS1) as a genetic marker. Fungal diversity was estimated and compared between speleothem and rock wall surfaces and its variation with distance from the natural entrance of the cave was quantified. Effects of environmental factors and nutrient concentrations in speleothem drip water at different sample sites on fungal diversity were also examined. Sequencing revealed 2219 fungal operational taxonomic units (OTUs) at 95% similarity. Speleothems supported a higher fungal richness and diversity than rock walls, but community membership and the taxonomic distribution of fungal OTUs did not differ significantly. OTU richness and diversity were negatively correlated with distance from the natural cave entrance. Community membership and taxonomic distribution of fungal OTUs differed significantly between the front and back of the cave. There was no observed effect of drip water nutrient concentration on fungal community structure. The third study examined fungal community structure from bat guano over the course of a year. There was no significant difference in fungal OTU richness, diversity, or community membership and taxonomic affiliations among sampling times. There were no significant differences in nutrient concentrations of guano samples among sampling times. Nutrient concentration did have a significant effect on community structure, especially the level of nitrogen and calcium.
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The seasonality, diversity and ecology of cavernicolous guano dependent arthropod ecosystems in southern AustraliaMoulds, Timothy A. January 2006 (has links)
Includes copies of author's previously published works / Guano deposits in caves form a rich food resource supporting diverse arthropod communities. Guano piles consist of distinct micro - habitats, fresh, moist, highly basic guano and older, dry, slightly acidic guano. Micro - habitat variation is strongly controlled by seasonal guano deposition that, in turn, effects the structure of arthropod communities. The maternity chamber of Bat Cave, Naracoorte, South Australia, contains extensive guano deposits supporting 38 species from three classes and 12 orders. This community was studied to determine spatial and temporal variation of arthropod communities, and biogeographic relationships between different regions in Australia. Species richness forms a positive linear relationship with pH, in situ moisture content and guano deposition. Many species show strong associations with fresh guano and hence are strongly seasonal, although some species are present throughout the year. Arthropod community structure in winter was found to be more closely related to prior summer arthropod structure than to subsequent seasons. Starlight Cave near Warrnambool, western Victoria, the only other maternity site for Miniopterus schreibersii bassanii, contained 43 species from 39 families and 14 orders. Seven species are common to both caves. The community structure of Starlight Cave was found to be more homogeneous than Bat Cave with samples clustering by season rather than sample year as was the case at Bat Cave. Different cave morphology was found to significantly alter the micro - habitat conditions and, hence, community structure in Starlight Cave compared with Bat Cave. Migration of guano associated arthropods at local, regional and continental scales was assessed using mtDNA and allozyme electrophoresis the pseudoscorpion genus Protochelifer as a model organism. Phylogenetic tree reconstruction revealed a wide geographic distribution of cavernicolous species across southern Australia. Cave colonisation is believed to have occurred only once, followed by dispersal to the Nullarbor Plain and other caves in south - eastern Australia. Dispersal was possibly phoretic on cave bats or occurred prior to aridification of surface environments that currently restricts migration. The distribution of guano - associated arthropods from arid, semi - arid and monsoonal karst areas in Australia are compared with temperate south - eastern Australia. Different climatic areas show large biogeographical differences in community structure, although similar families ( Urodinychidae, Reduviidae, Anobiidae, Carabidae and Tineidae ) are present in many Australian guano communities. Several potential mechanisms of dispersal are discussed including phoresy, colonisation from soil, terrestrial migration and interstitial cavities. Endemism to specific caves cannot be definitely assigned to any species, although 13 species show restricted distribution. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2006.
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A Bat-Guano-Derived δ<sup>15</sup>N and δ<sup>13</sup>C Record of Paleoenvironmental Change: Zidită Cave, RomaniaCleary, Daniel Martin 27 October 2015 (has links)
Because nitrogen isotopes are fractionated along the soil-plant-insect-bat-guano pathway, it may be possible to reconstruct environmental and climatic changes reflected in the nitrogen isotopic composition of guano. A 1.5-m core of bat guano from Zidită Cave (western Romania) provides a record of climatic and anthropogenic influence on the regional nitrogen cycle and paleoenvironmental controls on nitrogen transforming processes. Increasing and decreasing trends of nitrogen isotopic composition (δ15N values) correspond well with changes in the influence of farming practices, deforestation, and forest expansion. These influences likely had a significant effect on the openness of the nitrogen cycle, resulting in changes in δ15N values of soil, plants, and ultimately guano. While δ15N values have gradually decreased since AD 1700, decadal trends towards more positive values at AD 1840 and 1920 coincide with increases in tree pollen (forest recovery). Additionally, the accumulation of relatively15N-depleted guano coincides with periods of increased fire frequency, deforestation, and crop/herbaceous pollen (agricultural practices).
δ13C record of bulk guano indicates that carbon isotopic variation results from changes in water availability. Comparison of δ13C to δ15N indicates that there is a significant correlation between nitrogen and carbon isotopic composition of guano. When water availability was high (low δ13C values), δ15N values of bulk guano trend towards higher values. Although this connection to climate is the opposite of the findings from previous work correlating δ15N values of plant foliage and precipitation amount, the relationship between nitrogen isotopic values and water availability still appears to have merit. Based on these findings, δ15N of guano appears to be a signal for changes in N cycling of the Mada region that occurs, primarily in response to the precipitation received, further modified by intense changes in anthropogenic activity.
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