• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 13
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 22
  • 22
  • 9
  • 6
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

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 years

Walter Mesquita Filho 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.
12

Changing the Stories We Live By: Revolutionizing the North American Model of Wildlife Conservation Through Transformative Conservation

Burroughs, Tess Marie January 2022 (has links)
As biodiversity continues to diminish worldwide, an interrogation of long-standing conservation discourse is needed to reformulate a new conservation rhetoric that confronts the socio-ecological complexities of the world and reorients the relationship between humans and nature. Using ecologically sensitive critical discourse analysis, this research investigates the dominant ideologies perpetuated within an iteration of mainstream American wildlife discourse and explores opportunities for transformative conservation alternatives. Critical discourse analysis is performed on the State Wildlife Action Plans policy framework, which serve as the United States’ primary comprehensive wildlife conservation strategies that guide states in the preservation of fish and wildlife. Analysis of the State Wildlife Action Plans Report and Best Practices for State Wildlife Action Plans documentation revealed three dominant ideologies constructed and perpetuated within this conservation program, summarized as “Human Centrality,” “Animals as Resources,” and “The Supremacy of the Economic.” These three ideologies are manifestations of the overarching worldview of Anthropocentrism. After identifying the potentially harmful impacts associated with these ideologies, new stories inspired by insight from various environmental philosophies, Indigenous beliefs, and historical conservation leaders that align with the tenets of transformative conservation are created. These three new, alternative stories are: “Honoring the Intrinsic Value of Nature,” “Humans and Nature Rejoined,” and “Decentering the Economic.” By disentangling the hegemonic ideologies and power relations upheld within American conservation discourse, novel ways of thinking inspired by transformative conservation can be forged to combat biodiversity loss.
13

Exploring connections in social-ecological systems : The links between biodiversity, ecosystem services, and human well-being in South Africa

Hamann, Maike January 2016 (has links)
A key challenge of the Anthropocene is to advance human development without undermining critical ecosystem services. Central to this challenge is a better understanding of the interactions and feedbacks between biodiversity, ecosystem services and human well-being, which interact in dynamic and complex social-ecological systems. These relationships have been the focus of much work in the past decades, however more remains to be done to comprehensively identify and quantify them, especially at larger scales. In this thesis, a social-ecological systems approach is adopted to investigate connections between biodiversity, ecosystem services and human well-being in South Africa. The country’s high levels of biological and socio-economic diversity, as well as its emerging economy make South Africa an interesting case for exploring these connections. Using data from a variety of public sources, and at different sub-national scales, the thesis first identifies and analyses a variety of bundles of ecosystem service use. Based on these bundles, three social-ecological system archetypes were identified and mapped in South Africa, namely the green-loop (high overall use of local ecosystem services), transition, and red-loop (low overall use of local ecosystem services) systems. Further analysis explored the social and ecological drivers of these patterns, and found the distribution of systems mainly influenced by social factors including household income, gender of the household head, and land tenure. Second, this thesis uses human well-being indicators to construct, analyse and map multi-dimensional human well-being bundles. These bundles were found to spatially cluster across the landscape, and were analysed for congruence with the ecosystem service use bundles. Discrepancies in the expected overlap of ecosystem service use and human well-being were highlighted and concur with findings elsewhere and the ongoing debate in the literature on the impacts of time-lags, indicator choice and scale of these interactions. Third, biodiversity in South Africa was analysed by employing an indicator of biodiversity intactness (BII) at the population level. The BII was found to have declined by 18.3% since pre-industrial times. Biodiversity loss was linked to the potential supply of ecosystem services, as well as human well-being patterns. A potential threshold at 40% biodiversity loss was detected, beyond which population abundances decline sharply. Finally, the thesis examines multiple perspectives on ecosystem services in sustainability research, including the social-ecological systems perspective, and discusses the complementarity of the different perspectives in furthering a deeper understanding of the connections between people and ecosystems. The social-ecological systems perspective employed throughout the empirical work presented in this thesis contributed towards cross-cutting insights, the testing of new kinds of data and the development of new approaches, all of which represent important steps towards unravelling the connections between biodiversity, ecosystem services and human well-being, and contributing to the key Anthropocene challenge of sustainable development. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript. Paper 4: Manuscript.</p>
14

Situating adscriptions of value on Nature's Contributions to People : The case of traditional farmers in San Pedro, Paraguay.

Barranco Blasco, Martín January 2018 (has links)
This thesis focus on the unidimensional adscriptions of value behind industrial soybeans production in Paraguay. The thesis aims to present non-economic Nature’s Contributions to traditional farmers’ quality of life, the role of farmers’ traditional knowledge to display these contributions and the efficiency of such knowledge regarding high productive demands. From a theoretical framework based on nature’s contributions to people, ecosystem services, knowledge systems and conservation, the thesis formulates the following research questions: 1) What drives the prioritization of a single economic value on nature’s contributions to people in rural Paraguay? 2) What is the value of non-economic nature’s contributions, and what is the role of traditional farmers on displaying these values? The study mostly relies in primary data obtained through semi-structured interviews conducted during fieldwork period in the study area of San Pedro, Eastern Paraguay. The results present a plural assessment on nature’s contributions and the adaptation of small farmers to modern farming techniques. The thesis concludes that a perspective dominated by unidimensional value can be socially motivated within the rush for development in Paraguay, a concept tied to economic growth and modernization. In addition, nature’s contributions displayed by small farmers suggest that community-based conservation could represent a more sustainable approach for the farmers’ needs and the current environmental challenges of the country.
15

An investigation into the socio-economic factors and community perception in the direction of the conservation and management of the wetland : a case study of Thohoyandou Block F.

Ndou, Avhatakali Christopher 30 October 2012 (has links)
MPM / Oliver Tambo Institute of Governance and Policy Studies
16

Arable plant diversity in conventionally managed farmland of Northwest Germany - Current state and a participative approach to increase farmland biodiversity

Wietzke, Alexander 12 August 2020 (has links)
No description available.
17

Ekologisk Kompensation : Utmaningar och möjligheter inom bostadssektorn / Ecological Compensation : Challenges and possibilities in the real estate sector

Baghestani, Aidin January 2023 (has links)
Förlust av biologisk mångfald och tillhörande ekosystemtjänster klassas idag som en av de allvarligaste globala miljöutmaningarna mänskligheten står inför. Till följd av den globala urbaniseringen ökar efterfrågan på fastigheter, där städer växer till sig genom förtätning och utglesning. Utfallet blir en latent samhällsekonomisk kostnad i form av förlust av bostadsnära natur och urbana ekosystemtjänster. Ekologisk kompensation är ett framträdande koncept som tillämpas för att motverka förlust av biologisk mångfald. I denna studie har möjligheterna med ekologisk kompensation i samband med fastighetsutveckling i Sverige analyserats. Resultaten visar att incitament för frivilliga investeringar i ekologisk kompensation kan komma att öka i samband med förändringarna av EU:s taxonomiförordning och adopteringen av miljöcertifieringar. Vidare påvisas sambandet mellan ökade bostadsvärden och ekosystemtjänster. De största utmaningarna som stagnerar normalisering av ekologisk kompensation förefaller att grunda sig i avsaknaden av intern målsättning, skepticism och brister i samverkan med svenska kommuner. / Biodiversity loss and deprivation of ecosystem services are one of the most significant global environmental challenges that humanity faces today. As a consequence of global urbanization, the demand for housing and real estate in urban areas grow through urban densification and urban sprawl. This results in a latent societal cost which manifests itself through loss of greenspace and urban ecosystem services. Ecological compensation is a prominent tool that can be utilized to counteract losses of natural capital. In this study the possibilities of ecological compensation in the context of real estate development in Sweden has been analyzed. The results convey that incentives for voluntary investments in ecological compensation may increase due to the amendments of the EU Taxonomy as well as the adaptation of environmental certifications. Furthermore, correlations between property values and ecosystem services have been elucidated. Moreover, the biggest challenges that seem to impede normalization of ecological compensation underlie in perceptual factors, the lack of internal goal-setting and the shortcomings of collaboration with the Swedish municipalities.
18

Understanding the immediate and time-delayed effects of deforestation on biodiversity in the Gran Chaco

Semper-Pascual, Asunción 23 November 2020 (has links)
Landnutzungswandel ist eine der Hauptursachen von Biodiversitätsverlust. In den Tropen und Subtropen führt eine Ausweitung von Agrarflächen zu vermehrter Abholzung der Wälder. Selbst wenn zukünftige Waldrodungen vermieden werden können, ist ein weiterer Artenrückgang sehr wahrscheinlich, da viele Arten zeitverzögert auf Veränderungen reagieren. Die Hauptziele dieser Arbeit waren die Auswirkungen vergangener und aktueller Landnutzung auf Biodiversität im argentinischen Chaco besser zu verstehen und Ansätze zu entwickeln, um negative Effekte schon vor einem lokalen Aussterben zu erkennen. Der argentinische Chaco ist aufgrund seiner Landnutzungsgeschichte, den hohen Abholzungsraten und der hohen Biodiversität bestens für eine solche Untersuchung geeignet. Meine Arbeit zeigt, dass der Artenreichtum an Vögeln und Säugetieren stark durch vergangene Landschaftsmuster beeinflusst wurde, was auf zeitverzögerte Reaktionen auf Landnutzungswandel hindeutet, sowie darauf, dass ein Teil der momentan vorkommenden Arten durch vergangene Landnutzungsänderungen noch aussterben wird. Die zeitverzögerten Reaktionen sind hauptsächlich eine Folge von Lebensraumfragmentierung, mehr noch als von Lebensraumverlust. Meine Ergebnisse zeigen, dass das Vorkommen von Ameisenbären seit 1985 stark rückläufig ist, insbesondere seit 2000, als die Ausweitung von Agrarflächen besonders stark zunahm. Abschließend konnte ich zeigen, dass Pekaris meist in abgelegenen Regionen mit hohem Waldanteil vorkommen, sowie dass physiologischer Stress bei Pekaris negativ mit Nahrungsverfügbarkeit korreliert, jedoch nicht mit Abholzung. Meine Arbeit legt nahe, dass Abholzung generell zum Artensterben im argentinischen Chaco beiträgt. Während manche Arten sehr schnell verschwinden, sterben andere nicht direkt aus, was ein Zeitfenster für Naturschutzmaßnahmen eröffnet. Die hier vorgestellten Ergebnisse können dabei helfen solche Zeitfenster in von Abholzung bedrohten Gebieten zu identifizieren. / Land-use change is a primary driver of biodiversity loss. During recent decades, the tropics and subtropics have witnessed accelerating deforestation rates, resulting in widespread extinctions. Even if further deforestation was to be avoided, species would likely continue to disappear due to delays in their responses to land-use change. The goals of this thesis were to provide a better understanding of the effects of past and contemporary land use on biodiversity in the Argentine Dry Chaco, and to develop approaches that capture the impacts of land-use change on biodiversity before local extinctions occur. The Argentine Dry Chaco provides an excellent scenario for this purpose due to its dynamic land-use history, the high deforestation rates, and its high biodiversity levels. At the community level, I found that species richness of birds and mammals was influenced by past landscape patterns, suggesting time-delayed responses to land-use change and the evidence of an extinction debt. These time-delayed responses were due to habitat fragmentation rather than habitat loss. At the population level, I found that giant anteater occupancy decreased particularly after 2000 when agriculture expanded rapidly. My results further suggested that land-use change had substantial indirect effects on species’ populations. Finally, I assessed the effects of deforestation on collared peccaries at the population and individual level. Peccary occupancy was highest in areas with high woodland cover. Where peccaries were present, physiological stress was negatively correlated with food availability. Overall, this thesis shows that deforestation is driving species to extinction in the Argentine Dry Chaco. While some species may disappear quickly following deforestation, extinctions of others may not be immediate, providing an opportunity to prevent those extinctions. The approaches presented in this thesis help to identify those opportunities in dynamic landscapes such as deforestation frontiers.
19

Local and Landscape Management of Biological Pest Control in Oil Palm Plantations

Nurdiansyah, Fuad 03 May 2016 (has links)
No description available.
20

Biofonia : A citizen science service to monitor biodiversity

Toriseva, Jenni January 2016 (has links)
An increasing amount of both physical and mental layers keep distancing urban dwellers from the biophysical envi- ronment that we often call nature. Environmental psycholo- gists have coined the term ‘extinction of experience’ to de- scribe the decreasing amount of encounters urban dwellers have with the natural environment. With the depletion of these experiences we have less relation to the natural world. And what we cannot relate to, we find hard to value. The intent has been to explore new ways urban dwelling adults could interact with the natural environment in order to help them relate to the abstract notion of biodiversity. The final concept is inspired by expert and user insights gathered through ethnographic research methods. The resulting design concept is a service and product eco- system that is based in the field of soundscape ecology.

Page generated in 0.0503 seconds