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561.
The dominant discourse in 20th century UK food and agricultural policies of a liberal, free trade agenda was modified at the
turn of the 21st to embrace ecological sustainability and “food security.” The latter term has a long international history;
the relationship between issues of technical production and equality of distributional access are also much debated. The paper
examines shifts in UK policy discourse in the context of international research, policy, and initiatives to promote food security,
and highlights the implications for social justice in and through the food system. 相似文献
562.
Verónica Reyes-Galindo Juan Pablo Jaramillo-Correa Karina Carrasco Nava Alejandra Elizabeth De-la-Rosa-González David Flores Flores Mauricio Martínez Luis Alberto Monroy-De-la-Rosa Miguel Ángel Morelos Zamora Billy Emmanuel Ramírez Morales Oliver Tanui Ramírez Morales María del Pilar Rodríguez Maurilio Salazar Zamora Claudio Zamora Callejas Rafael Zamora Callejas César Zamora Tonatiuh Zamora Victor Alejandro González-Camacho Erick Rebollo Ricardo Torres-Jardón Ana Wegier Alicia Mastretta-Yanes 《Conservation biology》2023,37(5):e14112
Peri-urban forest monitoring requires indicators of vegetation damage. An example is the sacred fir (Abies religiosa) forests surrounding Mexico City, which have been heavily exposed to tropospheric ozone, a harmful pollutant, for over 4 decades. We developed a participatory monitoring system with which local community members and scientists generated data on ozone tree damage. Santa Rosa Xochiac rangers (13) used the digital tool KoboToolBox to record ozone damage to trees, tree height, tree ages, tree condition, tree position, and whether the tree had been planted. Thirty-five percent of the trees (n = 1765) had ozone damage. Younger trees had a lower percentage of foliage damaged by ozone than older trees (p < 0.0001), and asymptomatic trees tended to be younger (p < 0.0001). Symptomatic trees were taller than asymptomatic trees of the same age (R2c = 0.43, R2m = 0.27). Involving local communities facilitated forest monitoring and using digital technology improved data quality. This participatory system can be used to monitor forest condition change over time and thus aids restoration efforts driven by government or local communities’ interests, facilitating local decision-making. 相似文献
563.
564.
Christopher J. Lemieux Mark Groulx Elizabeth Halpenny Heather Stager Jackie Dawson Emma J. Stewart 《Environmental Communication: A Journal of Nature and Culture》2018,12(5):653-671
Rapid environmental change in vulnerable destinations has stimulated a new form of travel termed “last chance tourism” (LCT). Studies have examined the risks of LCT, while leaving potential opportunities within this new tourism market largely underexplored. Results of survey (n?=?399) research in Jasper National Park, Canada reveal that a LCT motivation influences decisions to visit this iconic Canadian destination, and suggest that this motivation is linked to a desire to learn about the impacts of climate change on the Athabasca Glacier. Findings suggest there may be short to medium term opportunities associated with LCT, including promoting climate change ambassadorship through management interventions. This paper discusses a range of possible education, interpretive, and outreach activities that might be employed at LCT destinations. It outlines the relative merits (or what we refer to as “uneasy benefits”) of promoting the glacier and other LCT destinations within a protected areas management and climate change adaptation context. 相似文献
565.
Elizabeth R. Smith 《Environmental monitoring and assessment》2000,64(1):9-15
Regional Vulnerability Assessment (ReVA) is an approach to place-based ecological risk assessment that is currently under development by EPA's Office of Research and Development. The pilot assessment will be done for the mid-Atlantic region and builds on data collected for the Environmental Monitoring and Assessment Program. ReVA is being developed to identify those ecosystems most vulnerable to being lost or degraded in the next 5 to 50 years and to elucidate which stressors cause the greatest risk to ecosystem goods and services. The goal here is not exact predictions, but an early warning system to identify and prioritize the undesirable environmental changes we should expect over the next few decades. As such, ReVA represents a new risk paradigm for EPA that will require innovative approaches to combine existing knowledge, focus new research, and synthesize many types of information into a meaningful assessment designed to inform environmental decision-makers about future environmental risk. 相似文献
566.
Contemporary estimates of atmospheric nitrogen deposition to the watersheds of New York State, USA 总被引:1,自引:0,他引:1
Atmospheric inputs of reactive nitrogen (N) to ecosystems are a particular concern in the northeastern USA, including New York State, where rates of atmospheric N deposition are among the highest in the nation. We calculate the seasonal and annual spatial variations of contemporary inorganic atmospheric N deposition loading to multi-scale watersheds across New York State using numerous monitoring datasets of precipitation and ambient atmospheric N concentrations. Our models build upon and refine previous efforts estimating the spatial distribution of N deposition. Estimates of total inorganic wet deposition (NH4-N + NO3-N) across New York ranged from 4.7 to 10.5 kg ha(-1) yr(-1) under contemporary conditions (averaged 2002-2004), and both seasonal and annual predicted rates of inorganic N deposition (NH4-N, NO3-N, and total) fit relatively well with that of observed measurements. Our results suggest that "hot spots" of N deposition are, for the most part, spatially distributed according to geographic positions (i.e., relative location from sources and the Great Lakes system) and elevation. We also detect seasonal variations in deposition, showing that total wet atmospheric inorganic N deposition inputs to watersheds (extracted from the four-digit HUC calculations) are highest during the spring (mean = 2.4 kg ha(-1), stddev = 0.29) and lowest during the winter months (mean = 1.4 kg ha(-1), stddev = 0.23). Results also suggest that wet NO3(-) consistently comprises a slightly higher proportion of wet N deposition than wet NH4+ throughout watersheds of New York, ranging from 2.5 to 6.1 kg NO3-N ha(-1) yr(-1) compared to NH4+, which ranges from 2.2 to 4.4 kg NH4-N ha(-1) yr(-1). 相似文献
567.
María A. Rubio Irene Fuenzalida Elizabeth Salinas Eduardo Lissi Ralf Kurtenbach Peter Wiesen 《Environmental monitoring and assessment》2010,162(1-4):209-217
CO/CO2 ratios have been measured in different locations of Santiago de Chile city. Measurements were carried out in a tunnel (prevailing emissions from cars with catalytic converter) and close to heavy traffic streets. Concentrations measured along the city traffic tunnel or temporal profiles of concentrations measured near heavy traffic streets allow an estimation of CO/CO2 ratios emitted from mobile sources. Values obtained range from 0.0045 ± 0.0006 to 0.0100 ± 0.0004 and depend on the prevailing type of mobile sources. In particular, lowest values were found close to a street with heavy traffic dominated by diesel-powered public transportation, while the highest values were found at the city tunnel. Places located near streets of mixed mobile sources (public buses and cars) showed intermediate values. Average CO/CO2 ratios are compatible with emission factors proposed for Santiago’s main mobile sources. 相似文献
568.
Connectedness to nature,place attachment and conservation behaviour: Testing connectedness theory among farmers 总被引:3,自引:0,他引:3
The aim of this study was to explore the relationship between pro-environmental behaviour and two forms of emotional association: attachment to place and connectedness to nature. This relationship is explored in the context of farmers' management of native vegetation on their properties. A postal survey was conducted to measure the extent to which farmers felt connected to nature and to their property. The survey also measured vegetation management behaviours and associated valued outcomes. A total of 141 farmers in northwest Victoria, Australia, completed the survey. Results showed that vegetation protection behaviours increased with connectedness to nature (CNS), although CNS accounted for only a modest amount of the variation in behaviour. Place attachment was not related to management behaviours. Further analysis suggested that the relationship between CNS and management behaviour was mediated by importance given to environmental benefits of vegetation management. The findings lend weight to studies showing a relationship between CNS and more simple conservation behaviours (e.g. recycling). The findings are also consistent with frameworks suggesting that emotional association with nature leads to an expanded sense of self and greater valuing of non-human species, and so to pro-environment behaviour. This demonstrates the importance of using a range of instrumental and more affective strategies to promote conservation behaviours. 相似文献
569.
Particulate matter (PM) has long been recognized as an air pollutant due to its adverse health and environmental impacts. As emission of PM from agricultural operations is an emerging air quality issue, the Agricultural Particulate Matter Emissions Indicator (APMEI) has been developed to estimate the primary PM contribution to the atmosphere from agricultural operations on Census years and to assess the impact of practices adopted to mitigate these emissions at the soil landscape polygon scale as part of the agri-environmental indicator report series produced by Agriculture and Agri-Food Canada. In the APMEI, PM emissions from animal feeding operations, wind erosion, land preparation, crop harvest, fertilizer and chemical application, grain handling, and pollen were calculated and compared for the Census years of 1981-2006. In this study, we present the results for PM10 and PM2.5, which exclude chemical application and pollen sources as they only contribute to total suspended particles. In 2006, PM emissions from agricultural operations were estimated to be 652.6 kt for PM10 and 158.1 kt for PM2.5. PM emissions from wind erosion and land preparation account for most of PM emissions from agricultural operations in Canada, contributing 82% of PM10 and 76% of PM2.5 in 2006. Results from the APMEI show a strong reduction in PM emissions from agricultural operations between 1981 and 2006, with a decrease of 40% (442.8 kt) for PM10 and 47% (137.7 kt) for PM2.5. This emission reduction is mainly attributed to the adoption of conservation tillage and no-till practices and the reduction in the area of summer fallow land. 相似文献
570.
González PS Maglione GA Giordana M Paisio CE Talano MA Agostini E 《Environmental science and pollution research international》2012,19(2):482-491