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171.
E.?M.?NkoanaEmail author T.?Waas A.?Verbruggen C.?J.?Burman J.?Hugé 《Environment, Development and Sustainability》2017,19(5):1731-1760
The assumptions and empirical evidence linking climate change adaptation to development cooperation have led to the emergence of a range of climate change adaptation tools aiming at improving the quality of development cooperation initiatives in times of global change. In order to assess the quality of these tools, we develop an analytic framework to critically assess the social learning and sustainable development outcomes of climate change adaptation tools. The analytic framework defines project objectives, participation typology, participation tools, participation stages, scenarios development, modelling exercises, stakeholder analysis and risk communication strategies that support quality participation outcomes. 相似文献
172.
Jérémy Bonvoisin 《International Journal of Sustainable Engineering》2017,10(4-5):198-206
AbstractIn pursuit of coping mechanisms for the challenges of sustainable manufacturing, systematic methods have been developed to allow engineers to improve the ratio between products’ utility and environmental impact. These necessary efforts remain however limited if the surrounding production and consumption practices are not called into question at the same time. This article introduces open source product development as a potential approach for unlocking the limits of existing sustainable product design practices and to lead towards alternative and eco-efficient production and consumption practices termed as participative production. First, it discusses the potential advantages of this emerging practice in terms of environmental sustainability. Second, it provides a screened qualitative environmental analysis of 18 exemplary open source hardware products. Specific sustainable design principles implemented by these products are highlighted and discussed in order to identify challenges for further common research in the field of open source and sustainable product development. 相似文献
173.
Aurora Oliver de la Esperanza Alejandro Arenas Martínez Miriam Tzeek Tuz Ernesto Pérez-Collazos 《Journal of Coastal Conservation》2017,21(1):85-93
Marine coast modification and human pressure affects many species, including sea turtles. In order to study nine anthropogenic impacts that might affect nesting selection of females, incubation and hatching survival of loggerhead (Caretta caretta) and green turtle (Chelonia mydas), building structures were identified along a 5.2 km beach in Kanzul (Mexico). A high number of hotels and houses (88; 818 rooms), with an average density of 16.6 buildings per kilometer were found. These buildings form a barrier which prevents reaching the beach from inland, resulting in habitat fragmentation. Main pressures were detected during nesting selection (14.19% of turtle nesting attempts interrupted), and low impact were found during incubation (0.77%) and hatching (4.7%). There were three impacts defined as high: beach furniture that blocks out the movement of hatchlings or females, direct pressure by tourists, and artificial beachfront lighting that can potentially mislead hatchlings or females. High impacted areas showed lowest values in nesting selection and hatching success. Based on our results, we suggest management strategies to need to be implemented to reduce human pressure and to avoid nesting habitat loss of loggerhead and green turtle in Kanzul, Mexico. 相似文献
174.
A hydraulic jump is a turbulent shear flow with a free-surface roller. The turbulent flow pattern is characterised by the development of instantaneous three-dimensional turbulent structures throughout the air–water column up to the free surface. The length and time scales of the turbulent structures are key information to describe the turbulent processes, which is of significant importance for the improvement of numerical models and physical measurement techniques. However, few physical data are available so far due to the complexity of the measurement. This paper presents an investigation of a series of characteristic turbulent scales for hydraulic jumps, covering the length and time scales of turbulent flow structures in bubbly flow, on free surface and at the impingement point. The bubbly-flow turbulent scales are obtained for Fr = 7.5 with 3.4 × 104 < Re < 1.4 × 105 in both longitudinal and transverse directions, and are compared with the free-surface scales. The results highlight three-dimensional flow patterns with anisotropic turbulence field. The turbulent structures are observed with different length and time scales respectively in the shear flow region and free-surface recirculation region. The bubbly structures next to the roller surface and the free-surface fluctuation structures show comparable length and time scales, both larger than the scales of vortical structures in the shear flow and smaller than the scales of impingement perimeter at the jump toe. A decomposition of physical signals indicates that the large turbulent scales are related to the unsteady motion of the flow in the upper part of the roller, while the high-frequency velocity turbulence dominates in the lower part of the roller. Scale effects cannot be ignored for Reynolds number smaller than 4 × 104, mainly linked to the formation of large eddies in the shear layer. The present study provides a comprehensive assessment of turbulent scales in hydraulic jump, including the analyses of first data set of longitudinal bubbly-flow integral scales and transverse jump toe perimeter integral scales. 相似文献
175.
Ting?ZhangEmail authorView authors OrcID profile Fangxin?Fang Ping?Feng 《Environmental Fluid Mechanics》2017,17(5):959-979
Dam failures usually cause huge economic and life losses , especially in urban areas where there is a high concentration of inhabitants and economic actors. In order to understand the physical mechanisms of the formation and development of dam-break flooding, lots of efforts have been put into different types of modelling techniques. However, most of existing models are 1D (one-dimensional) or 2D models based on the shallow water equations. In this paper, we present a 3D numerical modelling investigation of dam-break flow hydrodynamics in an open L-shape channel. A newly developed 3D unstructured mesh finite element model is used here. An absorption-like term is introduced to the Navier–Stokes equations in order to control the conditioning of the matrix equation in the numerical solution process and thus improve the stability. A wetting and drying algorithm is used here to allow the free surface height to be treated with a high level of implicitness and stability. The 3D model has been validated by comparing the results with the published experimental data. Good agreement has been achieved at six selected locations. This study shows that the 3D unstructured mesh model is capable of capturing the 3D hydraulic aspects and complicated local flows around structures in simulation of dam-break flows. 相似文献
176.
José Thales da Motta Portillo Vinícius Londe Francisco Wagner Araújo Moreira 《Journal of Coastal Conservation》2017,21(1):139-144
In Brazil, few studies have been conducted about the assimilation of carbon and biomass accumulation in mangroves despite its great role as a carbon sink. In this sense, this study aimed to estimate the aboveground biomass (AGB) and carbon stocked by mangrove species in a stretch along the Piraquê-Açu River in southeastern Brazil, and to verify their relation with some soil parameters. For such, the height and diameter of all trees inside six plots of 100 m2 were measured and used to quantify AGB through an allometric equation, and soil samples were collected to calculate granulometry, humidity, time of infiltration and permeability. Multiple regressions were used to identify relations between AGB and soil parameters. A total of 296 trees were found in the area and the AGB and carbon assimilated were 2.92 t ha?1 and 1.46 t ha?1, respectively. Laguncularia racemosa was the most abundant species and contributed with 61% of these values. Only a positive relation between AGB/carbon of L. racemosa and soil humidity was found, probably due to the substrate characteristics which contain a large concentration of silt/clay, and may store more water and do not yet provide firmness to the roots. By comparison, this mangrove had a low amount of AGB and carbon stocked and has yet to develop structurally. Along with other ecological functions and its associated ecosystem services such as supplying food for the local community, these features highlight the importance to conserve the studied mangrove and the interlinked coastal ecosystems. 相似文献
177.
In current debates on emerging technologies for plant breeding in Europe, much attention has been given to the regulatory status of these techniques and their public acceptance. At present, both genetically modified plants with cisgenic approaches—using genes from crossable species—as well as transgenic approaches—using genes from different species—fall under GMO regulation in the EU and both are mandatorily labelled as GMOs. Researchers involved in the early development of cisgenic GM plants convey the message that the potential use and acceptance of cisgenic approaches will be seriously hindered if GMO regulations are not adjusted. Although the similar treatment and labelling of transgenic and cisgenic plants may be a legitimate concern for the marketability of a cisgenic GM plant, there are concerns around their commercialization that reach beyond the current focus on (de)regulation. In this paper, we will use the development of the cisgenic GM potato that aims to overcome ‘late blight’—the most devastating potato disease worldwide—as a case to argue that it is important to recognize, reflect and respond to broader concerns than the dominant focus on the regulatory ‘burden’ and consumer acceptance. Based on insights we gained from discussing this case with diverse stakeholders within the agricultural sector and potato production in Norway during a series of workshops, we elaborate on additional issues such as the (technical) solution offered; different understandings of the late blight problem; the durability of the potato plant resistance; and patenting and ownership. Hence, this paper contributes to empirical knowledge on stakeholder perspectives on emerging plant breeding technologies, underscoring the importance to broaden the scope of the debate on the opportunities and challenges of agricultural biotechnologies, such as cisgenic GM plants. The paper offers policy-relevant input to ongoing efforts to broaden the scope of risk assessments of agricultural biotechnologies. We aim to contribute to the recognition of the complex socio-ecological, legal and political dimensions in which these technological developments are entangled as a means to acknowledge, discuss and respond to these concerns and thereby contribute to more comprehensive and responsible developments within agricultural biotechnology. 相似文献
178.
Magnus Lund Katrine Raundrup Andreas Westergaard-Nielsen Efrén López-Blanco Josephine Nymand Peter Aastrup 《Ambio》2017,46(1):26-38
Insect outbreaks can have important consequences for tundra ecosystems. In this study, we synthesise available information on outbreaks of larvae of the noctuid moth Eurois occulta in Greenland. Based on an extensive dataset from a monitoring programme in Kobbefjord, West Greenland, we demonstrate effects of a larval outbreak in 2011 on vegetation productivity and CO2 exchange. We estimate a decreased carbon (C) sink strength in the order of 118–143 g C m?2, corresponding to 1210–1470 tonnes C at the Kobbefjord catchment scale. The decreased C sink was, however, counteracted the following years by increased primary production, probably facilitated by the larval outbreak increasing nutrient turnover rates. Furthermore, we demonstrate for the first time in tundra ecosystems, the potential for using remote sensing to detect and map insect outbreak events. 相似文献
179.
Daniela Iannazzo Alessandro Pistone Ida Ziccarelli Claudia Espro Signorino Galvagno Salvatore V Giofré Roberto Romeo Nicola Cicero Giuseppe D Bua Giuseppe Lanza Laura Legnani Maria A Chiacchio 《Environmental science and pollution research international》2017,24(17):14735-14747
Dendrimer-functionalized multi-walled carbon nanotubes (MWCNT) for heavy metal ion removal from wastewaters were developed. Triazole dendrimers (TD) were built directly onto the carbon nanotube surface by successive click chemistry reactions affording the zero- and first-generation dendrimer-functionalized MWCNT (MWCNT-TD1 and MWCNT-TD2). The Moedritzer-Irani reaction carried out on the amino groups present on the MWCNT-TD2 sample gave the corresponding α-aminophosphonate nanosystem MWCNT-TD2P. Both MWCNT-TD2 and MWCNT-TD2P nanosystems have been characterized by physical, chemical, and morphological analyses. Their chelating abilities towards the toxic metal ions Pb2+, Hg2+, and Ni2+ and the harmless Ca2+ ion have been experimentally evaluated in the two different sets of experiments and at the salt concentrations of 1 mg/mL or 1 μg/mL by inductively coupled plasma mass spectrometry (ICP-MS). The results of these studies pointed out the interesting chelating behavior for the phosphonated nanosystem towards the Hg2+ ion. The complexation mode of the best chelating system MWCNT-TD2P with mercury was investigated through density functional theory (DFT) calculations, suggesting a chelation mechanism involving the two oxygen atoms of the phosphate group. The synthesized dendrimers, supported on the multi-walled carbon nanotubes, have shown the potential to be used for the selective toxic metal ion removal and recovery. 相似文献
180.
Félix Schmitt Khac-Uan Do 《Environmental science and pollution research international》2017,24(29):22885-22913
Membrane fouling is a major concern for the optimization of membrane bioreactor (MBR) technologies. Numerous studies have been led in the field of membrane fouling control in order to assess with precision the fouling mechanisms which affect membrane resistance to filtration, such as the wastewater characteristics, the mixed liquor constituents, or the operational conditions, for example. Worldwide applications of MBRs in wastewater treatment plants treating all kinds of influents require new methods to predict membrane fouling and thus optimize operating MBRs. That is why new models capable of simulating membrane fouling phenomenon were progressively developed, using mainly a mathematical or numerical approach. Faced with the limits of such models, artificial neural networks (ANNs) were progressively considered to predict membrane fouling in MBRs and showed great potential. This review summarizes fouling control methods used in MBRs and models built in order to predict membrane fouling. A critical study of the application of ANNs in the prediction of membrane fouling in MBRs was carried out with the aim of presenting the bottlenecks associated with this method and the possibilities for further investigation on the subject. 相似文献