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131.
As ecovillages present themselves as models of low-carbon living measuring the Ecological Footprint (EF) of an ecovillage serves both to validate that claim and to examine the component features of how the EF is achieved. This article examines the first measurement of the EF of Ireland’s only ecovillage, situated in the village of Cloughjordan in county Tipperary. The objectives here were to measure the EF of the ecovillage at the household scale and then to use the EF to provide meaningful feedback and reflective learning on human carbon intensity to the ecovillage residents. Various methods were applied in this action research to achieve high levels of engagement and potent communication of what could be learnt from the EF. This article places a particular focus on the necessary adaptation of an original EF method, on how it was implemented in the ecovillage, on the results obtained and on how these were communicated to the residents. The bottom-up component EF method samples consumption data at source and in so doing appoints consumption reflection and responsibility in ways the more remote compound method can not. The strategic combination of this specific quality with co-creation method aims to meaningfully engage and motivate a settlement to reduce its carbon intensity. According to the methodology, the ecovillage residents overshoot the fair earth share by 10% needing 1.1 planets to sustain their lifestyles. It is planned that subsequent to this intervention future measurements will show whether the overshoot has reduced. 相似文献
132.
The organic sector is in an ongoing, but somewhat ambiguous, process of differentiation. Continuing growth has also entailed intensified competition and the emergence of conventional structures within the sector. Producers are under pressure to adapt their terms of production to these developments, bearing the risk that the original values and principles of organic farming may become irrelevant. To confront these tendencies and maintain their position on the market, organic producers and processors have launched a number of organic–fair initiatives. As some consumers attach importance to ethical aspects of consumption, these actors sense market opportunities in such quality differentiation. This article presents results of a study on current organic–fair criteria, as formulated by such initiatives. All of them define standards of distributive, procedural and informational fairness, with fair prices for producers and processors and long-term agreements being core standards. We show that distributive and procedural fairness are closely linked. Although organic–fair initiatives and their main protagonists focus on external fairness, such as fair prices for farmers, thus far internal concerns, such as minimum wages or employee involvement, are of less importance. The initiatives exemplify the differentiation of quality-oriented organic food producers in highly competitive markets. They have the potential to revitalise the original values of the sector and contribute significantly to ethical standardization therein. In order to make a substantial contribution to future development of the sector, a critical examination of aspects of internal fairness as well as the formulation of appropriate standards in this field is recommended. 相似文献
133.
The Mediterranean deep-water kelp Laminaria rodriguezii is an endangered species in the Adriatic Sea
134.
Maria Byrne Natalie A. Soars Melanie A. Ho Eunice Wong David McElroy Paulina Selvakumaraswamy Symon A. Dworjanyn Andrew R. Davis 《Marine Biology》2010,157(9):2061-2069
Climate change driven ocean acidification and hypercapnia may have a negative impact on fertilization in marine organisms
because of the narcotic effect these stressors exert on sperm. In contrast, warmer, less viscous water may have a positive
influence on sperm swimming speed and so ocean warming may enhance fertilization. To address questions on future vulnerabilities
we examined the interactive effects of near-future ocean warming and ocean acidification/hypercapnia on fertilization in intertidal
and shallow subtidal echinoids (Heliocidaris erythrogramma, H. tuberculata, Tripneustes gratilla, Centrostephanus rodgersii), an asteroid (Patiriella regularis) and an abalone (Haliotis coccoradiata). Batches of eggs from multiple females were fertilized by sperm from multiple males in all combinations of three temperature
and three
\textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} treatments. Experiments were placed in the setting of projected near-future conditions for southeast Australia, an ocean
change hot spot. There was no significant effect of warming and acidification on the percentage of fertilization. These results
indicate that fertilization in these species is robust to temperature and
\textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} fluctuation. This may reflect adaptation to the marked fluctuation in temperature and pH that characterises their shallow
water coastal habitats. Efforts to identify potential impacts of ocean change to the life histories of coastal marine invertebrates
are best to focus on more vulnerable embryonic and larval stages because of their long time in the water column where seawater
chemistry and temperature have a major impact on development. 相似文献
135.
Community gardens and sustainable land use planning: A case-study of the Alex Wilson community garden 总被引:1,自引:0,他引:1
An analytical account of the history and aspirations of the Alex Wilson Community Garden in Toronto provides an ideal opportunity to examine the connections between two typically distinct enterprises: ecological restoration and community gardening. These are both important contemporary ecological movements, but are rarely combined in a single project that demonstrates the principles of sustainable land use and community planning. The garden is named in memory of Alex Wilson, a landscape designer, community activist and writer who worked and lived in Toronto, Canada. During his life, Wilson established a community garden which was eventually replaced by conventional urban development. After his death in 1993, friends and colleagues decided to honour his memory by establishing a permanent community garden in his name. The Alex Wilson Community Garden opened to the public in June 1998. The case-study explores how the garden reflects Wilson's work by linking community gardening and ecological restoration. These features are unified in Wilson's work as a means of nurturing relationships between people, communities and the landscape—relationships that are social, economic and ecological. In his book,The Culture of Nature: North American landscape from Disney to the Exxon Valdez (1991), Wilson argues that “we must build landscapes that heal and empower, that make intelligible our relations with each other and the natural world”. The Alex Wilson Community Garden illustrates in a practical manner the principles espoused by Wilson through its design, planning and functioning. The case-study reports on the innovative approach to landscape design taken in the garden, which reconstructs the natural and cultural history of southern Ontario, featuring lake-shore, agricultural and woodland sections. The garden has been planted exclusively with native plant species, and is expected to have a positive impact on local biodiversity. The planning process which led up to the design of the garden was participatory in nature, encompassing friends and colleagues of Alex Wilson, local residents and city planning officials, and made use of a number of planning tools not usually applied in an urban setting, including the granting of a conservation easement. The garden also addresses emerging issues associated with globalisation and large cities by providing food production opportunities for local residents, including a low-income housing complex and a nearby drop-in centre. Ecological monitoring and assessment of the naturalised area will be carried out by local residents. 相似文献
136.
Melanie B. Ruhiman Wade L. Nutter 《Journal of the American Water Resources Association》1999,35(2):277-290
ABSTRACT: Historic changes in stream channel morphology were investigated in the Georgia Piedmont to better understand the hydrologic processes and functioning of the region's riverine systems. USGS gaging station data and channel geomorphology data were collected from thirty study sites in the Upper Oconee River Basin for flood frequency analysis. Historic and modern (i.e., present-day) channel capacity discharge (i.e., overbank flow) was calculated using Manning's equation and historic channel cross-section records. The recurrence interval for overbank flow was estimated for each site from flood frequency data. Results indicate that channel expansion has occurred throughout the basin, especially in upper reaches. Recurrence intervals for modern overbank events were variable and generally high ranging from < 2 to > 500 years for first to third order streams. They were less variable and lower for fourth and fifth order streams, ranging from < 2 to 3 years. Potential depositional thresholds were identified that exemplify the complex response of sediment distribution patterns throughout the basin. Results indicate overbank flows occur less frequently now than they once did due to historic accelerated sedimentation and subsequent channel expansion. One application of these findings is that these basin processes are likely applicable across the region and may impact the hydrologic functioning of associated Piedmont riverine wetlands that depend on flooding regimes. 相似文献
137.
Thomas K. Rudel Birthe Paul Douglas White I. M. Rao Rein Van Der Hoek Aracely Castro Maryline Boval Amy Lerner Laura Schneider Michael Peters 《Ambio》2015,44(7):685-693
The increased use of grain-based feed for livestock during the last two decades has contributed, along with other factors, to a rise in grain prices that has reduced human food security. This circumstance argues for feeding more forages to livestock, particularly in the tropics where many livestock are reared on small farms. Efforts to accomplish this end, referred to as the ‘LivestockPlus’ approach, intensify in sustainable ways the management of grasses, shrubs, trees, and animals. By decoupling the human food and livestock feed systems, these efforts would increase the resilience of the global food system. Effective LivestockPlus approaches take one of two forms: (1) simple improvements such as new forage varieties and animal management practices that spread from farmer to farmer by word of mouth, or (2) complex sets of new practices that integrate forage production more closely into farms’ other agricultural activities and agro-ecologies. 相似文献
138.
The degradation of spiramycin induced by ultraviolet (UV) irradiation was studied at pH 3–4, 6–7 and 8–9 using high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. Furthermore, the influence of hydrogen peroxide and oxygen on the photodegradation was investigated. Three degradation products were observed in the presence of oxygen and four in the absence of oxygen. The degradation kinetics were monitored as mass area-time curves, analyzed and described using subsequent follow-up reaction first-order models. The m/z values of the degradation products were determined to be 160, 322 and 366, the latter representing two separate products, the sugar moieties of spiramycin. Remainders of the macrocycle or the intact lactone ring of spiramycin were not observed, since the conjugated π-electron system was assumed photoexcited and thus undergoing photodegradation and fast destruction of the ring. The kinetic of the degradation of spiramycin itself was described using a first-order model. The degradation was accelerated upon addition of hydrogen peroxide. In contrast, systematic acceleration depending on pH could not be found. The absence of oxygen did not lead to any significant acceleration. The findings are interpreted in terms of the effectiveness of advanced oxidation processes and their potential use as a fourth purification step in wastewater treatment plants. 相似文献
139.
Sarah L. Close Franco Montalto Philip Orton Adrienne Antoine Danielle Peters Hunter Jones 《Local Environment》2017,22(4):508-522
In the wake of Hurricane Sandy and other recent extreme events, urban coastal communities in the northeast region of the United States are beginning or stepping up efforts to integrate climate adaptation and resilience into long-term coastal planning. Natural and nature-based shoreline strategies have emerged as essential components of coastal resilience and are frequently cited by practitioners, scientists, and the public for the wide range of ecosystem services they can provide. However, there is limited quantitative information associating particular urban shoreline design strategies with specific levels of ecosystem service provision, and research on this issue is not always aligned with decision context and decision-maker needs. Engagement between the research community, local government officials and sustainability practitioners, and the non-profit and private sectors can help bridge these gaps. A workshop to bring together these groups discussed research gaps and challenges in integrating ecosystem services into urban sustainability planning in the urban northeast corridor. Many themes surfaced repeatedly throughout workshop deliberations, including the challenges associated with ecosystem service valuation, the transferability of research and case studies within and outside the region, and the opportunity for urban coastal areas to be a focal point for education and outreach efforts related to ecosystem services. 相似文献
140.
Melissa Hughes Stephen Nowicki William A. Searcy Susan Peters 《Behavioral ecology and sociobiology》1998,42(6):437-446
One hypothesis for the function of song repertoires is that males learn multiple song types so that they may share songs
with neighbors, allowing them to match during territorial interactions. In at least one song sparrow population, in Washington,
territorial males share a high proportion of song types with their neighbors and use these shared songs in matching. We recorded
song sparrows in Pennsylvania and quantified sharing of whole songs and song segments. We found that song sharing is an order
of magnitude less common in the Pennsylvania population. We found sharing of song segments to be significantly more common
than the sharing of whole songs in three of the five fields we examined, while we found no significant differences between
whole and partial song sharing in the remaining two fields. Finally, we found no evidence that sharing is greater between
birds in the same field compared to birds in different fields. Taken with the data from Washington song sparrows, these results
provide evidence for intraspecific geographic variation in the organization of song repertoires, and suggest that song sharing
has not been a strong selective force in the evolution of song repertoires in song sparrows as a species. Furthermore, Washington
and Pennsylvania song sparrows differ in how they learn song, in that Washington birds copy whole songs, while Pennsylvania
birds appear to copy and recombine song segments, as has been found in laboratory studies of song learning. Thus both song
learning and the function of song repertoires differ between populations of song sparrows. Such intraspecific geographic variation
offers a unique opportunity to explore the ecological and historical factors which have influenced the evolution of song.
Received: 30 June 1997 / Accepted after revision: 8 March 1998 相似文献