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Climate Change and Land-use Change Impacts on BumblebeesSoroye, Peter 10 January 2022 (has links)
Biodiversity is declining across the globe, and human-driven climate change and land-use change are among the primary drivers of this loss. Understanding the mechanisms causing declines is critical for developing effective conservation and management strategies which will not only slow biodiversity loss, but reverse it. This is relevant for virtually all species on the planet, but given the ecosystem services that they provide, pollinators are an especially important group in which to study this. Among the wild pollinators native to North America and Europe, bumblebees (Bombus) are a particularly important and beautiful group. In this thesis, I identify how climate change and land-use change interact to influence population and community change in North American and European bumblebees, and I explore the potential role of protected areas in mitigating declines. I find that climate change has increased local extinction risk for bumblebees by exposing them to temperatures beyond their historic tolerances, and I introduce a broadly applicable method which improves prediction of this climate change-related risk (Chapter 2). Examining the interactions between climate change and land-use change shows that the risk from increasing temperatures and temperature extremes is worse in historically degraded areas, and that climate change and land-use change may be driving biotic homogenization in bumblebee communities. Yet, landscape-scale patterns suggest that human land-use can be managed to have minimal, or even positive, effects on pollinators (Chapter 3). In the face of these global pressures, protected areas represent one way to conserve species. I find that increasing the amount of protected area in a region, regardless of size or management category of the protected areas, is related to reduced local extinction risk for bumblebees across North America and Europe. This benefit is especially strong in areas with high human land-use, highlighting the importance of protected areas in highly human-dominated landscapes (Chapter 4). The work within my thesis improves our understanding of how climate change and land-use change drive shifts in species and communities, and can inform on the effectiveness of specific conservation actions from gardens and urban greenspaces, to Other Effective Area-Based Conservation Measures (Chapter 5).
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Wildlife Town Center: Reimagining Landmark Mall as a Space for Reconnecting with the Urban Flora and FaunaCoates, Ashley Nicole 13 July 2021 (has links)
Urban development typically displaces or extirpates wildlife and decreases habitat. While some species such as the grey squirrel and raccoon adapt well to urban living, other species are less successful due to a lack of habitat or the loss of other species. As urbanization continues, the way that humans develop land and interact with species living on that land must be reevaluated. One development model that has been common in the Washington DC area is multi-use development. This development type accommodates various land uses in a small area. The layout of multi-use developments typically includes a central open area for events surrounded by retail and restaurants on the ground level and apartments and office space above. This creates a community where people have all of their needs for goods, housing, and work met within a small area. Another name for these types of multi-use developments is a Town Center. One of the newest proposed multi-use developments in the Washington DC area is at the former Landmark Mall location. The development aims to revitalize the now closed Landmark Mall in Alexandria, Virginia. As a design in development, the Landmark Mall Redevelopment Plan is a prime opportunity to explore a new concept for development: a wildlife town center. In my experience, typical Town Centers are not designed for wildlife. They are designed for heavy human foot traffic with plant selections and surfaces to withstand such traffic. How might a town center be re-imagined to support wildlife and also provide for humans? Animal Aided Design is one strategy. The process of Animal Aided Design takes a sampling of species that could live in a landscape and provides the critical needs for those species. This thesis takes the process of Animal Aided Design and applies it to the Landmark Mall Redevelopment Plan. While the design focuses on five particular bird species, the intention is to create conditions that will suit many more than those five species and that the site will attract a variety of birds as year-round residents, as well as those passing through during migration or staying for the breeding season. The project creates a novel habitat to help increase the viable living and foraging areas for wildlife and protects wildlife populations, while giving people the opportunity to find joy in their interactions with other species. / Master of Landscape Architecture / Urban development decreases available habitat and causes wildlife to move to new areas or perish. While some species such as the grey squirrel and raccoon adapt well to urban living, other species are less successful due to a lack of habitat or the loss of other species. As development in urban areas continues, the way that humans develop land and interact with species living on that land must be reevaluated. One development model that has been common in the Washington DC area is multi-use development. This development type accommodates various types of businesses and housing to exist near each other in a small area. The layout of multi-use developments typically includes a central open area for events surrounded by retail and restaurants on the ground level and apartments and office space above. This creates a community where people have all of their needs for goods, housing, and work met within a small area. Another name for these types of multi-use developments is a town center. One of the newest proposed town center developments in the Washington DC area is at the former Landmark Mall location. The development aims to revitalize the now closed Landmark Mall in Alexandria, Virginia into a place for community gathering. As a project in development, the Landmark Mall Redevelopment Plan is a prime opportunity to explore a new concept for development: a wildlife town center. In my experience, typical Town Centers are not designed for wildlife. They are designed to withstand people walking around with their children and pets. The plant selection in these areas are not typically native and have little benefit to the local wildlife. How might a town center be re-imagined to support wildlife and also provide for humans? One would take an approach that is more holistic and designs for the basic needs of wildlife as well as the humans. This strategy is called Animal Aided Design. This thesis takes the process of Animal Aided Design and applies it to the Landmark Mall Redevelopment Plan. While the design focuses on five particular bird species, the intention is to create conditions that will suit many more than those five species and that the site will attract a variety of birds as year-round residents, as well as those passing through during migration or staying for the breeding season. The project creates a novel habitat to help increase the viable living and foraging areas for wildlife and protects wildlife populations, while giving people the opportunity to find joy in their interactions with other species.
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Disturbance factors related to conservation of biodiversity in large-scale ecological networksJoubert, Lize 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Globally, habitat transformation causes biodiversity loss, with the transformed matrix often affecting the disturbance regime in remnant natural patches. In South Africa, significant parts of the Indian Ocean coastal belt and grassland biomes have been transformed into commercial forestry plantations of alien trees, which are detrimental to local biodiversity. Consequently, large scale ecological networks (ENs) of remnant natural vegetation, maintained areas (e.g. firebreaks) and special landscape features (e.g. rocky outcrops and wetlands) have been implemented among forestry compartments to offset the negative effect of this land use on biodiversity. Different grassland areas, which constitute a major portion of ENs, were managed in different ways, as governed by their primary purpose (e.g. fire protection or conservation). The overall aim of this study was to determine how grassland floral and grasshopper herbivore communities responded to different disturbances (mowing, burning and grazing), and how we can adjust management of the major disturbances to effectively conserve these major components of biodiversity in ENs.
Sampling was carried out in the commercial forestry ENs in the lower-elevation Zululand area and adjacent reserve area iSimangaliso Wetland Park, as well as in the forestry ENs in the higher-lying Midlands and adjacent iMpendle Nature Reserve. Both the reserves or protected areas (PAs) acted as reference sites, while other sites were chosen to represent the predominant disturbances in ENs at each locality: mowing, annual vs. longer-rotation burning, time since last fire, and domestic cattle grazing. In the Zululand subtropical grassland (chapter 2), I explored the effect of frequent mowing on firebreaks, and the effect of patch size and isolation on plant communities in non-firebreak natural areas of the EN. Frequent mowing resulted in plant species loss and a shift in species composition of firebreaks. Furthermore, small, isolated patches in the EN far away from the PA border had lower plant species richness and greater species turnover than wide, interconnected corridors near the PA border, which, in turn, was similar to reference sites in the PA. As plant species were lost from frequently-mown firebreaks and small, isolated patches in the EN, I recommend that this management practice should be confined to demarcated areas (e.g. forestry compartment edges and firebreaks) and that creation of wide, interconnected corridors should be prioritized when designing ENs.
In higher elevation Afromontane grassland (chapter 3), I investigated the effect of annual burning on plant communities in firebreaks by comparing them to less frequently burned grassland in the EN and PA, respectively. Grazing by domestic cattle was taken as an embedded factor for firebreak and less frequently burned sites in the EN. There were three firebreak types: annually-burned with heavy cattle grazing (plantation firebreaks), annually-burned with light cattle grazing (peripheral firebreaks), and annual burning without cattle grazing (PA firebreaks). Burned reference grassland in the EN and PA hosted plant communities that were similar in species richness, composition and turnover. This was also the case for lightly-grazed peripheral EN firebreaks and PA firebreaks. However, species composition and turnover of plantation EN firebreaks with heavy cattle grazing differed from that in the other two firebreak types. Although not significant (P<0.1), plantation EN firebreaks had less plant species than reference burned grassland in the EN, and all firebreak types had less plant species, lower species turnover and different species composition when compared to reference burned grassland in the PA. Annual burning of firebreaks, with and without cattle grazing, caused a significant shift in plant species composition and a reduction in plant species turnover. When annual burning was combined with heavy cattle grazing, plant species were lost, as was the case in plantation EN firebreaks. Therefore, I recommend that this management practice should be confined to firebreaks, and that cattle access to firebreaks should be strictly controlled. In Chapter 4, I considered the effect of cattle grazing (presence vs. absence, as well as intensity) on Afromontane grassland against the natural backdrop of variation caused by time since last fire in grassland with longer fire-return intervals (excluding all firebreaks). Lowest plant species richness and turnover occurred in unburned (i.e. burned >12 months prior to sampling), ungrazed grassland in the PA. Burning and grazing both caused a change in plant species composition that went hand in hand with an increase in plant species richness and turnover. However, burning (burned vs. unburned) only affected plant communities in ungrazed grassland in the PA. Similarly, the presence of large mammalian grazers (EN vs. PA) only affected plant communities in unburned grassland. Unburned plant communities grazed by domestic cattle in the EN were similar to those in the PA grazed by indigenous black wildebeest, indicating that cattle grazing simulates, at least to some degree, the effect of indigenous ungulate grazing. Nevertheless, heavily-grazed grassland had less plant species than moderately-grazed grassland in the EN. I recommend that burning and grazing should continue in grassland ENs, as these natural disturbances are necessary to maintain diverse and dynamic ecosystems. Nevertheless, managers should instigate cattle grazing with caution, as high intensity grazing can be detrimental to conservation efforts.
In Chapter 5, I examined the effect of annual burning, cattle grazing (presence vs. absence) and time since last fire on grasshopper assemblages in Afromontane grassland. In general, grasshoppers benefitted from disturbance, and were remarkably resilient to different disturbance regimes. Grasshopper species richness and their abundance were both greatest in annually-burned firebreaks with light cattle grazing, and lowest in moribund grassland in the PA which had not been burned for several years. Yet, time since last fire only affected grasshopper communities in the absence of large grazers (in the PA). None of the individual disturbances had an effect on the grasshopper assemblage. Rather, these insects responded to the combined effect of annual burning with cattle grazing. Sites were similar in grasshopper species richness, composition and abundance whenever either annual burning or cattle were absent, which suggests that these two disturbances drive changes in the grasshopper assemblage in these grasslands. Although grasshoppers benefited from annual burning with light cattle grazing, I would not recommend this disturbance regime outside firebreaks. Rather, management of other grassland areas in the EN should adapt longer fire-return intervals with a rotational cattle grazing system, so that undisturbed habitat is provided for other sensitive taxa.
In conclusion, grassland plants and grasshoppers benefited from some form of disturbance, but were lost from small, isolated patches in the EN, as well as from areas with high disturbance frequency and intensity. Simulation of natural disturbances (moderate levels of fire and grazing) in wide, interconnected corridors is necessary for maintaining diverse and dynamic grassland ecosystem in ENs among commercial forestry plantations. / AFRIKAANSE OPSOMMING: Omskepping van natuurlike habitat na lande of plantasies veroorsaak biodiversiteitsverlies wêreldwyd. Boonop het sulke veranderinge dikwels 'n effek op die versteurings binne-in oorblywende kolle natuurlike plantegroei wat verreikende gevolge kan hê. Groot gedeeltes van die Suid-Afrikaanse grasveldbioom is omskep in bosbou plantasies wat bestaan uit uitheemse bome wat 'n baie groot nadelige effek op plaaslike biodiversiteit het. Daarom is grootskaalse ekologiese netwerke (EN’e), wat bestaan uit oorblywende kolle natuurlike plantegroei, brandbane en spesiale habitattipes in die landskap (bv. rotsriwwe en vleilande), tussen bosbouplantasies geïmplimenteer met die doel om die negatiewe effek van plantasies op plaaslike biodiversiteit te verlig. Bestuur van grasvelde, wat 'n groot gedeel van EN’e uitmaak, wissel dikwels en hang af van hulle primêre doel (bv. beskerming van plantasies teen wegholveldbrande of natuurbewaring). Die doel van hierdie projek was om vas te stel hoe plant- en springkaangemeenskappe in grasvelde reageer op verskillende versteurings (grassny, brand en beweiding), en die optimale bestuur van die versteurings om die biodiversiteit in grasvelde beter te bewaar.
Steekproewe is geneem in EN’e tussen bosbouplantasies in die laagliggende Zululand en langsliggende wêrelderfenisgebied, iSimangaliso Wetland Park, asook in die hoërliggende Midlands en langsliggende iMpendle Natuurreservaat (NR). NR’e het as verwysing gedien waarteen die effek van grassny, frekwensie van brande, tydsverloop vanaf die laaste brand, en beweiding deur beeste, wat tipiese versteuringe in EN’e is, gemeet is.
In hoofstuk 2 het ek vasgestel wat die effek van grassnyfrekwensie op plantgemeenskappe in brandbane is, en hoe plantgemeenskappe in subtropiese grasveld in die res van die EN reageer op die grootte en strukturele isolasie van oorblywende kolle natuurlike plantegroei. 'n Hoë grassnyfrekwensie het 'n verandering in die spesiesamestelling van plantgemeenskappe in brandbane veroorsaak wat gepaard gegaan het met spesiesverlies. Terselfdertyd was daar minder plant spesies in klein, geïsoleerde kolle natuurlike plantegroei as wat daar in wyer, aaneenskakelende gange nader aan die natuurreservaatgrens was. Laasgenoemde het plantgemeenskappe bevat wat baie soortgelyk aan die in die natuurreservaat was. Daarom stel ek voor dat die skep van wye, aaneengeskakelde natuurlike habitat prioriteit moet geniet wanneer nuwe EN’e ontwerp word, en dat gras slegs gereeld gesny moet word in spesifieke, afgebakende areas (bv. brandbane). Die rede hiervoor is dat hierdie bestuurspraktyk nie bevorderlik was vir die bewaring van plantdiversiteit in EN’e nie. In hoofstuk 3 het ek gekyk hoe die plantgemeenskappe in brandbane daarop reageer om elke jaar gebrand te word deur hulle te vergelyk met Afrikaberg grasveld in die EN en NR wat minder gereeld gebrand word. Beweiding deur beeste is gesien as 'n integrale deel van die EN. Ek het onderskei tussen plantasiebrandbane met swaar beweiding, randbrandbane met ligte beweiding en brandbane in die NR sonder beweiding. Die plantspesiesamestelling van brandbane, met ligte of geen beweiding nie, het verskil van grasvelde wat minder gereeld gebrand word. Tog is die hoeveelheid plantspesies nie geraak nie. Alhoewel die plantgemeenskappe in ligbeweide brandbane soos die in onbeweide brandbane in die NR was, het die plantspesiesamestelling van beide verskille getoon wanneer hulle vergelyk is met plantasiebrandbane wat swaarder deur beeste bewei is. Plantspesierykheid in plantasiebrandbane was boonop heelwat laer as wat in NR grasvelde gevind is, en daar was heelwat meer kaal grond in plantasiebrandbane as in enige van die ander areas. Oor die algemeen het plantspesiesrykheid van brandbane nie daaronder gely om elke jaar gebrand te word nie, maar kwesbare plantgemeenskappe in brandbane het wel daaronder gely om swaar bewei te word. Daarom stel ek voor dat jaarlikse brande tot brandbane beperk word en dat beeste se toegang tot brandbane streng beheer word. In die hoofstuk 4 ondersoek ek die effek van beweiding deur beeste (teenwoordigheid teenoor afwesigheid, sowel as beweidingsintensiteit) op die plantspesiesrykheid en samestelling van gebrande en ongebrande Afrikaberg grasvelde wat minder gereeld gebrand word. Die minste plant spesies is aangeteken in ongebrande, onbeweide grasveld in die NR. Brande en beweiding het albei 'n effek op plantspesiesamestelling gehad wat gepaard gegaan het met 'n toename in plantspesiesrykheid. Plantgemeenskappe in grasvelde wat onlangs (<12 maande voor die steekproef geneem is) gebrand is, het slegs van die in ongebrande grasvelde verskil wanneer nie een van die twee areas bewei is nie. Op 'n soortgelyke trant het die teenwoordigheid van beeste (EN teenoor NR) slegs n effek gehad in ongebrande grasvelde. Ongebrande plantgemeenskappe in die EN wat deur beeste bewei is, was baie soos die in die NR wat deur swartwildebeeste bewei is. Dit dui daarop dat beeste die effek van inheemse wildsoorte tot 'n mate naboots. Des nieteenstaande die bogenoemde, het swaar-beweide grasvelde minder plantspesies gehad as grasvelde wat slegs matig bewei is. Ek stel voor dat brande en beweiding deel moet vorm van die bestuur van grasvelde in EN’e, want hierdie natuurlike versteuringe dra by tot 'n diverse, dinamiese grasveldekosisteem. Tog moet bestuurders versigtig wees wanneer hulle die plaaslike gemeenskap se beeste in EN’e toelaat, want swaar beweiding kan bewaringsinisiatiewe in die wiele ry. In hoofstuk 5 het ek die klem na springkane verskuif, en die effek van jaarlikse brande, beweiding deur beeste (teenwoordigheid teenoor afwesigheid) en tydsverloop sedert laaste brand op hierdie sensitiewe insekte in Afrikaberg grasvelde ondersoek. Alhoewel springkaangemeenskappe baat gevind het by versteuringe, het hulle nie beduidend gereageer op enige van die indiwiduele versteuringe nie. Die digste sprinkaan bevolking met die hoogste spesies diversiteit is aangeteken in brandbane in die EN wat liggies deur beeste bewei is. Darenteen is die laagste bevolking en spesies diversiteit aangeteken in grasvelde in die NR wat groot hoeveelhede dooie plantmateriaal bevat wat aandui dat hierdie grasvelde nie onlangs gebrand het nie. Springkaangemeenskappe in gebrande grasvelde het slegs van ongebrande grasvelde verskil wanneer nie een van die twee bewei is nie. Die sleutelkombinasie van versteuringe wat die rykheid en samestelling van springkaangemeenskape bepaal het, was 'n hoë brandfrekwensie (soos in brandbane) en beweiding deur beeste. Wanneer een van hierdie versteuringe afwesig was, was springkaangemeenskappe tussen verskillende areas dieselfde. Alhoewel springkaangemeenskappe daarby baat gevind het wanneer brandbane elke jaar gebrand en deur beeste bewei is, kan ek nie hierdie bestuurspraktyk vir die res van die EN aanbeveel nie. Grasvelde in die res van die EN behoort eerder minder gereeld (elke 2-4 jaar) gebrand en met 'n rotasiestelsel bewei word. Sodoende sal brandbane voorsien in die behoeftes van springkane, en die res van die EN in die behoeftes van sensitiewe taksa wat onversteurde habitat benodig om te floreer.
My slotsom is dat versteuringe nodig is om die volle diversiteit van plante en springkane en die dinamika binne-in grasvelde te bewaar. Tog verdwyn daar plantspesies uit areas met 'n hoë versteuringsintensiteit of frekwensie en klein, geïsoleerde kolle natuurlike plantegroei in die EN. Daarom beveel ek aan dat natuurlike versteuringe (brande en beweiding) matig toegepas moet word in wye, aaneengeskakelde gange in die EN. Hierdie benadering tot natuurbewaring kan biodiversiteit tussen bosbouplantasies beveilig teen verdere verlies.
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Effectively Communicating Biodiversity Loss Through Audiovisual StoriesRozema, Susan, Nowak, Jannika Katharina January 2021 (has links)
Communication about biodiversity loss is insufficient and audiovisual stories can help to effectively communicate the problem. This research developed the optimum communication criteria for communicating effectively about biodiversity loss through audiovisual stories. We created our theoretical framework by combining contemporary research about audiovisual stories concerning science and studies on effective communication about biodiversity loss and conservation. Based on this framework and using relevant multimodal critical discourse analysis tools, we built an analytical model. We applied the model to the analysis of three contemporary audiovisual stories concerning biodiversity loss: Rang-tan: the story of dirty palm oil (Greenpeace International, 2018), “Dream” (Wildlife Conservation Film Festival, 2016, original quotation marks), and The Birdman (Fordesman, 2020). The research findings demonstrate that current audiovisual stories lack aspects of the optimum communication criteria and that conservation communicators have not yet made use of the medium's full potential. Ideally, this thesis has the potential to encourage further research on how to communicate more effectively about biodiversity loss.
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Impacts of Plant Invasions in Native Plant–Pollinator NetworksParra-Tabla, Víctor, Arceo-Gómez, Gerardo 01 June 2021 (has links)
The disruption of mutualisms by invasive species has consequences for biodiversity loss and ecosystem function. Although invasive plant effects on the pollination of individual native species has been the subject of much study, their impacts on entire plant–pollinator communities are less understood. Community-level studies on plant invasion have mainly focused on two fronts: understanding the mechanisms that mediate their integration; and their effects on plant–pollinator network structure. Here we briefly review current knowledge and propose a more unified framework for evaluating invasive species integration and their effects on plant–pollinator communities. We further outline gaps in our understanding and propose ways to advance knowledge in this field. Specifically, modeling approaches have so far yielded important predictions regarding the outcome and drivers of invasive species effects on plant communities. However, experimental studies that test these predictions in the field are lacking. We further emphasize the need to understand the link between invasive plant effects on pollination network structure and their consequences for native plant population dynamics (population growth). Integrating demographic studies with those on pollination networks is thus key in order to achieve a more predictive understanding of pollinator-mediated effects of invasive species on the persistence of native plant biodiversity.
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Biodiversity and Business : Multiple Case-Studies on Biodiversity Strategy in SwedenGoaied, Amna, Sjöland, Christian January 2019 (has links)
Biodiversity loss has been stated as one of the greatest risks for the future society according to the World Economic Forum (2018, p. 5). A million species is risking extinction due to current societies’ practices according to a report published during the conduction of this study(Brondizio et al., 2019, p. 3). This situation of biodiversity has led an increasing amount of countries to enforce legislation which requires companies that work with land development to comply with no net loss goal. In Sweden, no such legislation existed with regards to biodiversity. Against this background, a group of seven companies in Sweden voluntarily chose to strive toward the goal of biodiversity net gain. According to BNG strategy, a company does not only avoid, minimise, restore and offset to reach the point where zero net loss of biodiversity is achieved, but goes farther to create a net gain. As it is not sufficient for companies to stop emissions in order to halt the loss of biodiversity, BNG practices can help mend and even reverse the negative impacts until a gain of biodiversity is attained. A greater understanding of the opportunities that companies can benefit from implementing BNG helps spread this practice across industries. No previous research within the business literature explains companies’ voluntary initiatives to embrace BNG. Therefore, this explorative study suggested the research question of what the drivers are encouraging companies to voluntarily work towards achieving biodiversity-net-gain in Sweden. Due to the lack of previous research about companies’ drivers to engage with BNG, our theoretical framework was found based on the drivers from business case for sustainability and CSR approaches as a factor to generate change. To be able to answer the research question, it was necessary to establish what BNG is and how it has developed from the concept of ecosystem services. Having an interpretivistic standpoint, this study was completed according to an inductive and deductive approach. This was in order to facilitate the exploratory nature that our qualitative and comparative study. We conducted a multiple-case study through semi-structured interviews with seven large companies in the context of Sweden. These businesses are considered as the most ambitious in working towards BNG’s goal. The findings from the primary data was complemented by secondary data about the companies, the status of current legislation in Sweden and the sustainability status in Sweden. As a result of this thesis, we found that cost and cost reduction, risk and risk reduction, sales and profit margin, reputation and brand value, attractiveness as employer, innovative capabilities, stakeholders and health and well-being of future society to all be drivers for BNG. By applying our theoretical framework in the Swedish context, the seven companies were identified to engage in a proactive corporate biodiversity behaviour. Business cases for biodiversity were identified in some of the companies.
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Die Bewahrung und Förderung der Biodiversität als theoretisch-praktische Herausforderung für den modernen Natur- und Umweltschutz / The conservation and advancement of biodiversity as a theoretical and practical challenge for modern nature and environment protectionLachnit, Silke 26 February 2018 (has links)
No description available.
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Invasão e estabelecimento de Digitonthopagus gazella (Coleoptera, Scarabaeidae) em Selvíria, MS e seus impactos na comunidade de besouros coprófagos nativos durante 22 anos / Invasion and establishment of Digitonthophagus gazella (Coleoptera, Scarabaeidae) in Selvíria, MS and its impacts on native dung beetle community during 22 yearsMesquita Filho, Walter 10 July 2017 (has links)
Invasões biológicas são uma das maiores ameaças à biodiversidade mundial. O estabelecimento de espécies exóticas, principalmente de insetos, em vários países ocorreu por meio da utilização de controle biológico, quando se introduz uma espécie exótica para o controle de outra. Em alguns casos, por diferentes motivos, espécies introduzidas com este objetivo acabaram se tornando invasoras. O besouro coprófago Digitonthophagus gazella é um destes exemplos. O objetivo desta tese foi avaliar o impacto de D. gazella sobre a abundância, diversidade e turnover de uma comunidade de besouros coprófagos nativos no Brasil. A comunidade foi amostrada semanalmente, e no mesmo local, desde novembro de 1989, através de armadilha luminosa, obtendo-se dados até novembro de 2015. A espécie exótica invadiu a área após quatro anos do início das coletas, tendo-se no presente estudo 22 anos de coletas semanais dessa espécie exótica introduzida. Na comunidade já havia outra espécie coprófaga exótica presente, Labarrus pseudolividus, que possui hábito residente de nidificação. A invasão por D. gazella modificou substancialmente a comunidade local. A abundância, diversidade e riqueza da comunidade nativa apresentavam tendência de aumento antes, passando a diminuir após a invasão. As espécies com o mesmo hábito de nidificação de D. gazella (escavador) não mostraram sinais de recuperação dos impactos, com todos os índices apresentando decréscimo contínuo desde a invasão, principalmente do turnover, tamanho populacional e riqueza de espécies. Espécies residentes, exibindo hábito similar a L. pseudolividus, foram capazes de recuperar o status após alguns anos, mantendo-se mais estáveis a partir do ano 15. Quando analisado o turnover da comunidade atual, ou seja, espécies nativas e exóticas, observou-se que toda a dinâmica da comunidade foi mantida pelas espécies exóticas. A partir da diminuição da abundância de D. gazella houve aumento na de L. pseudolividus, levando a uma aparente estabilidade na diversidade e turnover, a despeito do comportamento oposto observado na comunidade nativa. A partir da invasão por D. gazella, variáveis climáticas, fatores responsáveis principais pela característica da comunidade, passaram a execer menor influência. / Biological invasions are one of the major threats to the global biodiversity. The use of exotic species as agents of biological control is one way to contribute to invasions. In some cases, the introduced species became invasive. The tunneler dung beetle (DB) Digothophagus gazella is a good example. Released in many countries, including Brazil, to improve dung pad removal, the species quickly spread to new ones, where it is considered as an invasive species. The objective of this thesis was to evaluate impacts of D. gazella on the abundance, alfa-diversity and turnover of a native DB community in Brazil. Another exotic DB species, the dweller Labarrus pseudolividus, was present in the study area. The community was sampled weekly, at the same location, from November 1989 until November 2015 using a black light trap. The exotic species was first recorded four years after the beginning of sampling. The invasion by D. gazella changed significantly the native community. Abundance, diversity and richness were increasing during the first years, however they all decreased since the invasion. Species with the same nesting behavior of D. gazella (tunneler) were not able to recover from the impacts, with turnover, abundance and species richness continuously decreasing after the invasion. Dweller species on the contrary were able to partially recovery after some years, rebound its abundance and turnover since year 15. Results from the turnover analysis of the current community, which is native and exotic, showed that it has been influenced by both exotic species. Following the decrease in abundance of D. gazella and native species, L. pseudolividus was able to increase its abundance, leading to stabilization of the turnover despite the opposite observed in the native community. Since the invasion by D. gazella, weather variables became less important on the changes observed.
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Biodiversity loss and climate change: an eco-social analysisChurch, Daniel 22 August 2013 (has links)
This thesis analyzes the global ecological crisis. It divides the global ecological crisis in
to two major components: Climate change and biodiversity loss. Using a theoretical
methodology based on comparing and applying a variety of lenses from within
environmental sociology, the thesis asks and answers two questions: What are the causes
of the global ecological crisis, and how can we solve it? Drawing on the perspectives of
ecological modernization theory, ecological Marxism and deep ecology, the causes of
and solutions to the global ecological crisis are identified. The primary causes of the
crisis are found to be inefficient industrial technology, capitalism and an instrumentalist
and anthropocentric view of the natural world. The primary solutions, therefore, must
include a widespread shift towards clean and green technology, a transformative social
revolution, and a new ecocentric respect for the intrinsic value of non-human life. The
study offers many recommendations for policy makers.
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Biodiversity loss and climate change: an eco-social analysisChurch, Daniel 22 August 2013 (has links)
This thesis analyzes the global ecological crisis. It divides the global ecological crisis in
to two major components: Climate change and biodiversity loss. Using a theoretical
methodology based on comparing and applying a variety of lenses from within
environmental sociology, the thesis asks and answers two questions: What are the causes
of the global ecological crisis, and how can we solve it? Drawing on the perspectives of
ecological modernization theory, ecological Marxism and deep ecology, the causes of
and solutions to the global ecological crisis are identified. The primary causes of the
crisis are found to be inefficient industrial technology, capitalism and an instrumentalist
and anthropocentric view of the natural world. The primary solutions, therefore, must
include a widespread shift towards clean and green technology, a transformative social
revolution, and a new ecocentric respect for the intrinsic value of non-human life. The
study offers many recommendations for policy makers.
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