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  • 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.
581

Servi?os ecossist?micos urbanos: fixa??o de carbono nas ?reas de preserva??o permanente de Campinas-SP / Urban ecosystem services: carbon sequestration in the permanent preservation areas of Campinas-SP.

Ruschel, Rodrigo Semeria 21 December 2016 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-02-01T11:44:11Z No. of bitstreams: 1 RODRIGO SEMERIA RUSCHEL.pdf: 4638678 bytes, checksum: d4d1202cce0328177e98030dac7e0f3d (MD5) / Made available in DSpace on 2017-02-01T11:44:11Z (GMT). No. of bitstreams: 1 RODRIGO SEMERIA RUSCHEL.pdf: 4638678 bytes, checksum: d4d1202cce0328177e98030dac7e0f3d (MD5) Previous issue date: 2016-12-21 / This work presents the potential of carbon sequestration and provision of other ecosystem services in the Permanent Preservation Areas along the watercourses of the city of Campinas-SP. Also, the cost associated with the carbon sequestration service was calculated and how much the municipality would benefit from creating a market for the carbon credits generated in the reforestation projects in these areas. It was shown that the commercialization of credits would cover up to 46% of the project implementation costs. In addition to carbon sequestration, the recovery of PPAs along watercourses provides additional ecosystem services to the municipality, which if contemplated in the cost-benefit analysis of reforestation projects represent the largest portion of the total benefits. Therefore, the inclusion of the benefits generated by the additional ecosystem services has proved to be fundamental to make the recovery of PPAs economically viable. / Este trabalho apresenta o potencial de fixacao de carbono e provisao de demais servicos ecossistemicos das Areas de Preservacao Permanente ao longo dos cursos d?agua do municipio de Campinas-SP. Ainda, calculou-se o custo associado ao servico de fixacao de carbono e o quanto o municipio se beneficiaria ao criar um mercado para os creditos de carbono gerados nos projetos de reflorestamento destas areas. Foi demonstrado que a comercializacao dos creditos cobriria ate 46% dos custos de implantacao dos projetos. Alem da fixacao de carbono, a recuperacao das APPs ao longo de cursos d?agua proporciona servicos ecossistemicos adicionais ao municipio, e que se contemplados na analise custo-beneficio dos projetos de reflorestamento representam a maior porcao dos beneficios totais. Portanto, a inclusao dos beneficios gerados pelos servicos ecossistemicos adicionais mostrou-se fundamental para tornar a recuperacao das APPs economicamente viavel.
582

Pollinators in the city : Exploring the potential of urban environments as sites for conservation

Johner, Julia January 2018 (has links)
Insect pollinators provide indispensible ecosystem services for agricultural, natural and urban ecosystems, and have been declining drastically around the globe. These declines are largely due to fragmentation and loss of habitat resulting from urbanization and intensification of agriculture, and raise concerns over global food security. The purpose of this paper is to investigate the effects of urbanization on abundance, species richness and diversity of insect pollinators, and whether urban environments have potential as sites for conservation. Cities are highly heterogeneous environments with ample foraging and nesting opportunities and can house an abundance and diversity of pollinators. Urban environments can serve as refuges for many pollinator species. Effective city planning and mixed conservation strategies can help to promote healthy populations of insect pollinators in urban environments, which can help to stabilize populations in rural settings, thereby ensuring pollination services for agriculture and terrestrial ecosystems. / Pollinerande insekter (pollinatörer) bidrar med oumbärliga ekosystemtjänster till jordbruk och naturliga och urbana ekosystem, och de har minskat drastiskt i antal runt hela jorden. Dessa nedgångar orsakas till största del av habitatförstöring och -fragmentering, och väcker oro över den globala matsäkerheten. Syftet med den här uppsatsen är att undersöka hur urbanisering påverkar abundans, artrikedom och biodiversitet hos pollinatörer, samt om urbana miljöer har potential som platser för bevarande av pollinatörer. Städer är mycket heterogena områden med gott om matresurser och boplatser, och kan husera en mångfald av pollinatörer. Urbana miljöer lämpar sig bra som platser för bevarande av pollinatörer. Med effektiv stadsplanering och en blandning av olika bevarandestrategier kan städer uppehålla hälsosamma populationer av pollinatörer. Detta kan hjälpa till att stabilisera populationer på landsbygden och därmed säkerställa pollinationstjänster till såväl jordbruk som naturliga terrestra ekosystem.
583

Relations entre diversité des habitats forestiers et communautés de chiroptères à différentes échelles spatiales en Europe : implications pour leur conservation et le maintien de leur fonction de prédation / Relationships between forest habitat diversity and bat communities at different spatial scales in Europe

Charbonnier, Yohan 02 December 2014 (has links)
Les chiroptères sont reconnus comme de potentiels régulateurs des populations d’insectes. Ce sont aussi les mammifères européens pour lesquels les enjeux de conservation sont les plus importants. Ils trouvent dans les forêts des habitats favorables qui sont cependant menacés par les changements climatiques et la fragmentation. Il convient donc de mieux comprendre lesrelations entre les communautés de chiroptères, leurs habitats et leurs proies en forêt. L'objectif de cette thèse est de quantifier les effets, à différentes échelles spatiales, desprincipales composantes de l’habitat forestier sur l’activité, la richesse spécifique, la diversité fonctionnelle et la composition des communautés de chiroptères européens. Les résultats reposent sur des données collectées grâce à des protocoles expérimentaux en Aquitaine et dans les six pays du réseau de placettes forestières organisé par le projet FunDivEurope. De la parcelle au continent, l'accroissement de la diversité des essences forestières, de la proportion de feuillus et du bois mort, en augmentant les ressources en proies et en gîtes, ont des effets positifs sur les communautés de chiroptères. Ces effets, non stationnaires, se renforcent vers le nord avec la rigueur du climat. Nous confirmons également que les chiroptères forestiers, par leur réponse numérique et fonctionnelle aux densités de proie, peuvent limiter la démographie d’un insecte défoliateur. Des mesures de gestion, visant le renforcement des structures-clés des habitats forestiers, sont proposées pour favoriser la conservation des communautés de chiroptères et leur capacité de régulation des insectes ravageurs. / Insectivorous bats are increasingly recognized as potential regulators of pest insect populations.They also represent the group of European mammals with the most unfavorable conservation status. Forests are key habitats for many bat species but are currently under threat from climate change and fragmentation. It is therefore urgent to better understand the relationships between the bats, their prey and their habitats in forests. Our main objective was to quantify the effects, at multiple spatial scales, of the main attributes of forest habitats on the activity, species richness, functional diversity and composition of European bat communities. They were studied using manipulative experiments in Aquitaine plantation forests and automatic recordings in the network of exploratory plots set up in six European countries by the FunDivEurope project. From the plot to the continent scale, increasing tree diversity, amount of broad leaved trees and dead wood, had positive effects on bat communities through an increase in prey and roost resources. However these effects were not stationary, being stronger at higher latitudes, probably due to lower habitat carrying capacity in relation to harsher climatic conditions. In addition we experimentally demonstrated that the numerical and functional responses of bats to prey density could result in effective regulation of pine processionary moth populations. Forest management strategies aim at enhancing key habitat structures, are eventually proposed in order to improve the conservation of bats and to increase the service of pest regulation they can provide.
584

Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change

Gordon, Line January 2003 (has links)
The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. Although of great significance, this thesis shows that such a focus will not be sufficient for coping with freshwater related social-ecological vulnerability. The thesis illustrates that the terrestrial component of the hydrological cycle, reflected in vapour flows (or evapotranspiration), serves multiple functions in the human life-support system. A broader understanding of the interactions between terrestrial systems and freshwater flows is particularly important in light of present widespread land cover change in terrestrial ecosystems. The water vapour flows from continental ecosystems were quantified at a global scale in Paper I of the thesis. It was estimated that in order to sustain the majority of global terrestrial ecosystem services on which humanity depends, an annual water vapour flow of 63 000 km3/yr is needed, including 6800 km3/yr for crop production. In comparison, the annual human withdrawal of liquid water amounts to roughly 4000 km3/yr. A potential conflict between freshwater for future food production and for terrestrial ecosystem services was identified. Human redistribution of water vapour flows as a consequence of long-term land cover change was addressed at both continental (Australia) (Paper II) and global scales (Paper III). It was estimated that the annual vapour flow had decreased by 10% in Australia during the last 200 years. This is due to a decrease in woody vegetation for agricultural production. The reduction in vapour flows has caused severe problems with salinity of soils and rivers. The human-induced alteration of vapour flows was estimated at more than 15 times the volume of human-induced change in liquid water (Paper II).
585

The appreciation of nature and landscape by tourism service providers and visitors in the Ore Mountains (Germany)

Bastian, Olaf, Stein, Christian, Lupp, Gerd, Behrens, Jan, Renner, Christina, Grunewald, Karsten 29 May 2015 (has links) (PDF)
The paper presents empirical studies on the appreciation of nature and landscape in the Eastern Ore Mountains (Saxony, Germany) by tourism service providers (TSP) and visitors. Attractive landscape and experience of nature are the most important reasons to visit this region and to spend leisure time there. Particularly mountain meadows, raised bogs and mixed forests are highly appreciated. Deforestation, industrial development and the decline of biodiversity would reduce attractiveness for visitors. We also assessed whether the tourism sector is prepared to contribute to the funding of nature conservation and landscape management. Use of general tax revenues is favoured, but other modes would also be accepted, e.g. a nature tax. Willingness to pay (WTP) is ranging between €0.75 and €1.36 per guest per night by TSP, or between €1.06 and €2.73 per day by visitors. With respect to landscape preference and WTP we found in some cases significant differences among visitors, depending on region of residence, age and education level. A major part of the annual costs for nature conservation and landscape could be covered by public funds (taxes), if the results of the WTP approach were understood as a sign of societal demand and a call to action.
586

Einfluss von ökologischem Landbau und Landschaftskomplexität auf die Wirbeltierdiversität und Ökosystemfunktionen / Effects of farming practice and landscape complexity on vertebrate diversity and ecological functioning in agroecosystems

Fischer, Christina 20 May 2010 (has links)
No description available.
587

Ant community structure and biological control in Indonesian cacao agroforestry: long-term changes, land-use management and precipitation gradients / Struktur von Ameisengemeinschaften und biologische Kontrolle in Indonesischen Agroforstsystemen: Langzeitänderungen, Bewirtschaftungsintensität und Niederschlagsgradienten

Rizali, Akhmad 07 November 2011 (has links)
No description available.
588

Heterogeneity of peasant land use decision as an effect of differences financial and personal capitals in the area of Biosphere Reserve Podocarpus - El Cóndor , Ecuador

Maza Rojas, Byron Vinicio 18 November 2010 (has links)
No description available.
589

Economic valuation of of land use change - A case study on rainforest conversion and agroforestry intensification in Central Sulawesi, Indonesia / Die ökomische Bewertung des Landnutzungswandels - Eine Fallstudie über die Umwandlung von Regenwald und die Intensivierung von Agroforstsystemen in Zentral-Sulawesi, Indonesien

Juhrbandt, Jana 08 July 2010 (has links)
No description available.
590

Economic Valuation of Biological Diversity / Exploring Non-market Perspectives in the Vicinity of the Lore-Lindu National Park in Indonesia`s Central Sulawesi Region / Ökonomische Bewertung Biologischer Vielfalt / Untersuchung von Nicht-Markt Perspektiven in der Umgebung des Lore-Lindu Nationalparks in der indonesischen Region Zentralsulawesi

Glenk, Klaus 16 November 2006 (has links)
No description available.

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