• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 319
  • 105
  • 66
  • 51
  • 15
  • 15
  • 7
  • 4
  • 3
  • 3
  • 3
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 677
  • 677
  • 173
  • 126
  • 113
  • 103
  • 103
  • 88
  • 88
  • 87
  • 85
  • 81
  • 81
  • 78
  • 72
  • 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.
71

Managing for Urban Ecosystem Services: The Yongding River Ecological Corridor

January 2014 (has links)
abstract: Sustainability requires developing the capacity to manage difficult tradeoffs to advance human livelihoods now and in the future. Decision-makers are recognizing the ecosystem services approach as a useful framework for evaluating tradeoffs associated with environmental change to advance decision-making towards holistic solutions. In this dissertation I conduct an ecosystem services assessment on the Yongding River Ecological Corridor in Beijing, China. I developed a `10-step approach' to evaluate multiple ecosystem services for public policy. I use the 10-step approach to evaluate five ecosystem services for management from the Yongding Corridor. The Beijing government created lakes and wetlands for five services (human benefits): (1) water storage (groundwater recharge), (2) local climate regulation (cooling), (3) water purification (water quality), (4) dust control (air quality), and (5) landscape aesthetics (leisure, recreation, and economic development). The Yongding Corridor is meeting the final ecosystem service levels for landscape aesthetics, but the new ecosystems are falling short on meeting final ecosystem service levels for water storage, local climate regulation, water purification, and dust control. I used biophysical models (process-based and empirically-based), field data (biophysical and visitor surveys), and government datasets to create ecological production functions (i.e., regression models). I used the ecological production functions to evaluate how marginal changes in the ecosystems could impact final ecosystem service outcomes. I evaluate potential tradeoffs considering stakeholder needs to recommend synergistic actions for addressing priorities while reducing service shortfalls. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2014
72

Pedagogers syn på ekosystemtjänster och hållbar utveckling / Ecosystemservices and Education

Aalto, Glenn, Edman, Hanna January 2020 (has links)
No description available.
73

Essays on Spatially Diverse Values of and Preferences in Ecosystem Services / 生態系サービスの空間的に多様な価値や選好に関する研究

Kabaya, Kei 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21823号 / 農博第2336号 / 新制||農||1067(附属図書館) / 学位論文||H31||N5195(農学部図書室) / 京都大学大学院農学研究科生物資源経済学専攻 / (主査)教授 栗山 浩一, 教授 伊藤 順一, 教授 梅津 千恵子 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
74

Functions of Wetlands in Sweden : a literature review

Toth, Gergely Istvan January 2021 (has links)
The lack of cultural and economic recognition of the significance of wetlands arguably led to theirdevastating and rapid loss compared to other ecosystems. To reverse this trend and establish a reasonablevaluation of wetlands, the foundations of socio-ecological concepts were laid in late 20th century thatsuggested the acknowledgement of the functions, values, and services of ecosystems. Subsequently, inthe 21st century the scientific interest in wetland functionality is driven beyond mere conservationalefforts and includes the appropriation of their values for sustainable development, and the utilization oftheir functions as nature-based solutions to humanity’s growing environmental problems. In light of thistrend, this literature review outlines the most critical functions of Swedish wetlands and places them intheir contexts of significance. A meta-analysis of the scientific literature on Swedish wetlandswas conducted with the assessment of wetland functions, wetland types, and the drivers that motivatedeach study. To identify the most critical functions and their contexts, patterns and trends wereinvestigated among these categories. Results show that the most recognised functions of Swedishwetlands are their nutrient-pollutant retention, ecosystem maintenance, and carbon sink functions.Their connections to distinct drivers suggest that their values mainly lie in their potential tomitigate negative impacts of anthropogenic activities, such as eutrophication and global warming,and to support local and regional biodiversity. Synergies among these functions are alsodiscussed, as exemplified by dual-purpose constructed wetlands. Moreover, understudiedhydrological functions are thought to reflect their undervaluation and indicate possible risksattached to associated knowledge gaps. By summarising and contextualising the most importantfunctions, this literature review sheds light on the contemporary understanding and valuation ofwetland functions in Sweden. It is suggested that these novel perceptions effectively drive wetlandconstruction and restoration, the ever-more popular strategies to mitigate climate- and industryrelated risks. Consequently, the recognition, interpretation, and application of wetland functionswill all contribute to the future landscape composition of Sweden.
75

What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, Texas

Proctor, Jayce Alan 05 1900 (has links)
Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.
76

Evaluating trade-offs between agricultural productivity and long-term ecosystem services provision among maize farmers practising conventional and conservation agriculture in Kafue Zambia

Mwangana, Namulula January 2016 (has links)
Maize is a staple crop and underpins food security for Zambia. Maize productivity in Zambia is almost half the potential due to low uptake of conservation agricultural practices. This study tests the hypothesis of the trade-offs between agriculture productivity and long-term ecosystem services (ES) provision among maize farmers practising conventional agriculture on the one hand, and those practising conservation agriculture on the other hand, in Kafue district, Zambia. In addition, challenges which affect conservation agriculture uptake are assessed. Besides these challenges, the study notes that adoption of a new technology is also influenced by its efficiency, and therefore technical efficiency scores were estimated using the Stochastic Frontier Approach (SFA) to compare efficiency levels of the two agricultural systems. Kafue was purposefully selected as it is among the first districts where conservation agriculture was introduced. Through purposive and random sampling, the households surveyed were split into two distinct groups namely conservation agriculture (CA) farmers (treatment group) and conventional agriculture (CV) farmers (control group). The analysis significantly shows that farmers practicing CA have more knowledge than CV farmers about the capacity of conservation agriculture to reduce soil erosion, increase soil fertility, retain nutrients, mitigate pests and weeds and increase crop yield. However, both farming groups knew that CA helps conserve soils and that soil maintenance is important for food production. On the other hand, significantly, CV farmers knew more than CA farmers that CV reduces crop yield and increases soil erosion. On the other hand, CV farmers expressed a higher level of willingness to adopt CA practices than CA farmers who are unwilling to expand their area under CA. The study further shows that at least 55% of farmers practicing CA find inadequate labour to be the main challenge faced in CA. It appears that a policy that improves the farmers' knowledge on CA would help improve the uptake of CA. CA farmers were significantly more knowledgeable than CV farmers about the detrimental effects of CV, such as increasing air and water pollution, thus raising the need for training among CV farmers with emphasis on the effects of their farming system on the environment which affect the supply of ecosystem services. Efficiency is also a means of improving productivity hence the Stochastic Frontier Analysis (SFA) was employed to estimate technical efficiency levels in maize production. Using SFA, the study found that the technical efficiency of maize among CV farmers is 71.3% on average while that of CA farmers is 57.9% on average. Moreover, the study found that there was a significant difference (t=3.9854, P=0.0002) in the technical efficiency scores of the both CV and CA farmers. Nevertheless, the study also found that 77% of output variation among CA farmers can be explained by variation in technical efficiency. However, 33.4 % of total maize output can be explained by variation in technical efficiency among CV farmers. This means that CA farmers have a higher potential to increase their current output than CV farmers. Finally there was no significant difference in fertiliser usage between CA and CV farmers (t=1.3825, P=0.1700). Further, from SFA fertiliser responsiveness to maize output showed that a 1% increase in the use of synthetic fertiliser leads to 0.678% and 0% increase in maize output per hectare for CA and CV respectively at both 1% and 10% level of significance at the expense of water and air quality. Therefore, it can be concluded that there is a higher trade-off between maize production and water and air quality under conventional than under conservation agriculture. / Dissertation (MSc (Agric))--University of Pretoria, 2016. / Agricultural Economics, Extension and Rural Development / MSc (Agric) / Unrestricted
77

The Prolific Partition : Architecture as catalyst for nature reserve conservation structured in the in-between of Urban and Nature

Visagie, Armand 04 1900 (has links)
Nature reserves in the City of Tshwane are under threat from ecological and historically significant decay due to the less defined nature of these landscapes. Architecture in form, function and technology can be developed in the in-between of nature and urban to act as conservator for these nature reserves. Utilizing the natural resources of nature to produce products for the urban dweller within a space that conserves the historical protective layers of the site. The space of interaction between nature and urban becomes the conservator, acting as active protector in terms of sustainable production, education and urban dweller interaction with the nature reserve and its continuous history of protection. / Natuurreservate in die stad Tshwane word bedreig deur ekologiese en historiese betekenisverval weens die minder gedefinieerde aard van hierdie landskappe. Argitektuur in vorm, funksie en tegnologie kan ontwikkel word in die tussen ruimte van natuur en stedelike gebiede om as natuurbewaarder vir hierdie natuurreservate op te tree. Die natuurlike hulpbronne van die natuur kan gebruik word om produkte vir die stedelike inwoner te produseer binne ‘n ruimte wat die historiese beskermende lae van die terrein laat voortduur. Die ruimte van interaksie tussen natuur en stedelike word die bewaarder, wat optree as ‘n aktiewe beskermer in terme van volhoubare produksie, opvoeding en stedelike inwoner interaksie met die natuurreservaat en sy voortgesette geskiedenis van beskerming. / Mini Dissertation (MArch(Prof))--University of Pretoria, 2018. / Architecture / MArch(Prof) / Unrestricted
78

Kartläggning av ekosystemtjänster i Åresjön

Eriksson Norman, Emma January 2019 (has links)
Den utökade verksamheten i Åre har lett till en försämrad ekologisk status för den lokala sjön i Åre vid namn Åresjön. Enligt länsstyrelsen Jämtlands län så finns behovet av att åtgärder vidtas för att förbättra tillståndet i sjön. Denna studie har som syfte att bidra med information till framtida beslutsunderlag. Metoden som användes för att utföra studien valdes för att undersöka vilken data som finns tillgänglig för de olika ekosystemtjänsterna samt hur tillgänglig den informationen är. Studien utgick från enbart befintliga data samt en metod som används för att undersöka vilka indikatorer som finns kopplade till nyttjandet av ekosystemtjänsterna från Åresjön. Resultatet visar på att det finns flera ekosystemtjänster i Åresjön som har användarvärde i dagsläget. Vissa av de tjänsterna som belyses i studien har varit svåra att påvisa på grund av otillfredsställande tillgänglighet av information. Det finns flera indikatorer som visar på att ekosystemtjänsterna kopplade till Åresjön nyttjas i dagsläget. Slutsatserna av studien är att det finns ekosystemtjänster kopplade till Åresjön som idag har ett användarvärde men i och med att informationen om tjänsterna är begränsade så kan det inte utföras en komplett kartläggning av tjänsterna och dess värden. / The expanded operations in Åre have led to a deterioration of the ecological status of the local lake in Åre, named Åresjön. According to the county administration of Jämtland, there is a need for measures to improve the state of the lake. This study aims to provide information for future decision making. The method used to carry out the study was chosen to investigate what data is available about the different ecosystem services and how accessible that information is. The study was based on only existing data. Another method used in the study examines which indicators are linked to the use of ecosystem services from Åresjön. The result shows that there are several ecosystem services in Åresjön that have user value at the present time. Some of the services highlighted in the study have been difficult to detect due to unsatisfactory availability of information. There are several indicators that show that ecosystem services connected to Åresjön are currently being used. The conclusions of the study are that there are ecosystem services connected to Åresjön, which today have a user value, but because the information about the services is not limited, a complete mapping of the services and its values cannot be performed. / <p>2019-06-07</p>
79

Spatial and temporal variations of inundation and their influence on ecosystem services from a shallow coastal lake. A case study of Soetendalsvlei in the Nuwejaars catchment, South Africa

Carolissen, Mandy January 2021 (has links)
Philosophiae Doctor - PhD / Enhancing our understanding of wetland properties and the ecosystem services provided by wetlands within a dynamic landscape, is fundamental to ensuring appropriate management strategies for enhanced biodiversity and ecosystem benefits. With increased anthropogenic activities and the impacts of climatic variability, a better understanding of the factors influencing the water balance dynamics of wetlands can provide insight into how wetlands respond to change. The main aim of the research was to improve the understanding of the spatial and temporal availability of water and storage of a depression wetland in a semi-arid climate, and to relate these to ecosystem functions. As ecosystems are intricately connected to society, a secondary aim of the research was to gain insight to how wetland ecosystems, within a changing climate and landscape, provide benefits to society, and add value to human-wellbeing. Soetendalsvlei, a shallow freshwater depression, and one of the few coastal freshwater lakes of South Africa, was the focus of the research.
80

The Public Perception of Urban Stormwater Ponds as Environmental Amenities

Heller, Charlotte 09 April 2020 (has links)
Integrating green or blue space into cities can provide environmental and public health benefits which maximize urban sustainability. One type of green/blue infrastructure that has been understudied is urban stormwater ponds, which are used to manage stormwater runoff. Their performance is typically only evaluated in terms of hydrological functions, with little focus on their capacity to provide ancillary benefits to communities. In this exploratory study, an online survey was distributed to six neighbourhoods in the City of Ottawa, ON to gain insight into the social value of urban stormwater ponds. The results revealed that despite some disadvantages, most respondents visited their neighbourhood stormwater ponds regularly and largely appreciated the cultural ecosystem services provided by these ponds, such as opportunities for experiencing nature, especially wildlife, and outdoor recreation. These findings can be used to improve the multifunctionality of stormwater ponds and optimize both environmental and social sustainability outcomes.

Page generated in 0.0591 seconds