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881.
China produces the largest amount of pork in the world, which emits the largest amount of greenhouse gases (GHGs). This paper calculates GHG emissions from China’s hog production at the provincial level using newly published emission factors. Empirical results show that GHG emissions from China’s hog production mainly respond to the scale intensity. Capital abundance and income contribute positively to GHG emissions from hog production. Pork trade increases GHG emissions from China’s hog production with a significantly direct effect, reduces GHG emissions through indirect technique effects. 相似文献
882.
Mark Groulx Christopher J. Lemieux John L. Lewis Sarah Brown 《Journal of Environmental Planning and Management》2017,60(6):1016-1035
Parks and protected areas are a global ecological, social and health resource visited by over 8 billion people annually. Their use can yield substantial benefits, but only if a balance between ecological integrity and sustainable visitation is struck. This research explores the potential influence of climate-driven environmental change on visitation to North America's most popular glacier, the Athabasca Glacier in Jasper National Park, Canada. Photorealistic environmental visualizations were used to gauge visitors’ perceptions of environmental change and potential impacts on consumer behaviour. Results suggest that impacts could substantially diminish the site's pull as a tourism destination. Rather than improving visitation prospects, expert-proposed adaptations underestimated the importance of perceived naturalness and contributed to further potential decline. Findings are relevant to protected areas planning and management. They suggest that a natural path to climate change adaptation is the best way to support both ecological integrity and the long-term tourism pull of protected areas. 相似文献
883.
Improving Predictive Models of In‐Stream Phosphorus Concentration Based on Nationally‐Available Spatial Data Coverages
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Murray W. Scown Michael G. McManus John H. Carson Jr. Christopher T. Nietch 《Journal of the American Water Resources Association》2017,53(4):944-960
Spatial data are playing an increasingly important role in watershed science and management. Large investments have been made by government agencies to provide nationally‐available spatial databases; however, their relevance and suitability for local watershed applications is largely unscrutinized. We investigated how goodness of fit and predictive accuracy of total phosphorus (TP) concentration models developed from nationally‐available spatial data could be improved by including local watershed‐specific data in the East Fork of the Little Miami River, Ohio, a 1,290 km2 watershed. We also determined whether a spatial stream network (SSN) modeling approach improved on multiple linear regression (nonspatial) models. Goodness of fit and predictive accuracy were highest for the SSN model that included local covariates, and lowest for the nonspatial model developed from national data. Septic systems and point source TP loads were significant covariates in the local models. These local data not only improved the models but enabled a more explicit interpretation of the processes affecting TP concentrations than more generic national covariates. The results suggest SSN modeling greatly improves prediction and should be applied when using national covariates. Including local covariates further increases the accuracy of TP predictions throughout the studied watershed; such variables should be included in future national databases, particularly the locations of septic systems. 相似文献
884.
Helen L. Brown Christopher J. Walsh Tim D. Fletcher Sharyn RossRakesh 《Journal of Environmental Planning and Management》2016,59(1):79-97
Urban stormwater run-off is a threat to stream ecosystems. New approaches to stormwater management aim to protect urban streams from such impacts, by retaining, treating and using stormwater at its source. As up to ~50% of runoff from urban surfaces comes from private property, fostering stormwater retention requires effective householder engagement. We evaluated householder participation in the Little Stringybark Creek project, a stormwater retrofit programme aimed at waterway protection, using qualitative enquiry through formal and informal interviews to identify factors that influenced participation. Participation was governed by multiple factors, with financial incentives and personal co-benefits of tanks primary motivators, while process complexity and distrust were primary barriers. Results suggest an approach combining education to encourage review of subjective norms and attitudes, with incentives to mitigate behavioural controls can transform public behaviour towards sustainable stormwater management. 相似文献
885.
Zhaohao Shi Christopher A. Baker Sang In Lee Si Hong Park Sun Ae Kim 《Journal of environmental science and health. Part. B》2016,51(9):602-608
Salmonella serovars, one of the leading contributors to foodborne illness and are especially problematic for foods that are not cooked before consumption, such as fresh produce. The shipping containers that are used to transport and store fresh produce may play a role in cross contamination and subsequent illnesses. However, methods for quantitatively attached cells are somewhat variable. The overall goal of this study was to compare conventional plating with molecular methods for quantitating attached representative strains for Salmonella Typhimurium and Heidelberg on reusable plastic containers (RPC) coupons, respectively. We attached Salmonella enterica serovar Typhimurium ATCC 14028 and serovar Heidelberg SL486 (parent and an antibiotic resistant marker strain) to plastic coupons (2.54 cm2) derived from previously used shipping containers by growing for 72 h in tryptic soy broth. The impact of the concentration of sanitizer on log reductions between unsanitized and sanitized coupons was evaluated by exposing attached S. Typhimurium cells to 200 ppm and 200,000 ppm sodium hypochlorite (NaClO). Differences in sanitizer effectiveness between serovars were also evaluated with attached S. Typhimurium compared to attached S. Heidelberg populations after being exposed to 200 ppm peracetic acid (PAA). Treatment with NaClO caused an average of 2.73 ± 0.23 log CFU of S. Typhimurium per coupon removed with treatment at 200 ppm while 3.36 ± 0.54 log CFU were removed at 200,000 ppm. Treatment with PAA caused an average of 2.62 ± 0.15 log CFU removed for S. Typhimurium and 1.41 ± 0.17 log CFU for S. Heidelberg (parent) and 1.61 ± 0.08 log CFU (marker). Lastly, scanning electron microscopy (SEM) was used to visualize cell attachment and coupon surface topography. SEM images showed that remaining attached cell populations were visible even after sanitizer application. Conventional plating and qPCR yielded similar levels of enumerated bacterial populations indicating a high concordance between the two methods. Therefore, qPCR could be used for the rapid quantification of Salmonella attached on RPC. 相似文献
886.
Trails created by off-road vehicles (ORV) in boreal lowlands are known to cause local impacts, such as denuded vegetation,
soil erosion, and permafrost thaw, but impacts on stream and watershed processes are less certain. In Wrangell-St. Elias National
Park and Preserve (WRST), Alaska, ORV trails have caused local resource damage in intermountain lowlands with permafrost soils
and abundant wetlands and there is a need to know whether these impacts are more extensive. Comparison of aerial photography
from 1957, 1981, and 2004 coupled with ground surveys in 2009 reveal an increase in trail length and number and show an upslope
expansion of a trail system around points of stream channel initiation. We hypothesized that these impacts could also cause
premature initiation and headward expansion of channels because of lowered soil resistance and greater runoff accumulation
as trails migrate upslope. Soil monitoring showed earlier and deeper thaw of the active layer in and adjacent to trails compared
to reference sites. Several rainfall-runoff events during the summer of 2009 showed increased and sustained flow accumulation
below trail crossings and channel shear forces sufficient to cause headward erosion of silt and peat soils. These observations
of trail evolution relative to stream and wetland crossings together with process studies suggest that ORV trails are altering
watershed processes. These changes in watershed processes appear to result in increasing drainage density and may also alter
downstream flow regimes, water quality, and aquatic habitat. Addressing local land-use disturbances in boreal and arctic parklands
with permafrost soils, such as WRST, where responses to climate change may be causing concurrent shifts in watershed processes,
represents an important challenge facing resource managers. 相似文献
887.
Global warming is breeding social conflict: The subtle impact of climate change threat on authoritarian tendencies 总被引:1,自引:0,他引:1
Immo Fritsche J. Christopher CohrsThomas Kessler Judith Bauer 《Journal of environmental psychology》2012,32(1):1-10
Climate change can increase societies’ propensity to conflict by changes in socio-structural conditions (e.g., resource scarcity, migration). We propose an additional, subtle, and general effect of climate change threat via increases in authoritarian attitudes. Three studies in Germany and the UK support this suggestion. Reminding participants of the adverse consequences climate change may have for their country increased the derogation of societal groups that may threaten the collective (e.g., criminals) as well as general authoritarian attitudes. Salient climate change threats also led to system justification and approval of system supporting groups (e.g., judges) in those people who were highly identified with their nation. We discuss the implications of these findings for the explanation of authoritarian attitudes and the question of how societies may cope with the subtle social psychological effects of climate change. 相似文献
888.
Christopher J. Hoard Ralph J. Haefner William D. Shuster Rachel L. Pieschek Stephanie Beeler 《Journal of the American Water Resources Association》2020,56(1):82-99
A goal in urban water management is to reduce the volume of stormwater runoff in urban systems and the effect of combined sewer overflows into receiving waters. Effective management of stormwater runoff in urban systems requires an accounting of various components of the urban water balance. To that end, precipitation, evapotranspiration (ET), sewer flow, and groundwater in a 3.40‐hectare sewershed in Detroit, Michigan were monitored to capture the response of the sewershed to stormwater flow prior to implementation of stormwater control measures. Monitoring results indicate that stormflow in sewers was not initiated unless rain depth was 3.6 mm or greater. ET removed more than 40% of the precipitation in the sewershed, whereas pipe flow accounted for 19%–85% of the losses. Flows within the sewer that could not be associated with direct precipitation indicate an unexpected exchange of water between the leaky sewer and the groundwater system, pathways through abandoned or failing residential infrastructure, or a combination of both. Groundwater data indicate that groundwater flows into the leaky combined sewer rather than out. This research demonstrates that urban hydrologic fluxes can modulate the local water cycle in complex ways which affect the efficiency of the wastewater system, effectiveness of stormwater management, and, ultimately, public health. 相似文献
889.
Globally, tropical forests are being perturbed by human activity. Tropical vegetation constitutes some of the largest terrestrial
carbon stocks against the build up of greenhouse gases. In this paper, a local-scale case study utilising remote sensing methodology
in estimating forest loss is presented, for a section of tropical South Africa’s Soutpansberg Mountains where land use pressure
threatens some of the last remaining indigenous forests. Landsat TM images from October 1990, August 2000 and September 2006
were used, together with municipality level demographic data. Hybrid image classification techniques distinguished forest
cover on the images, which were classified into vegetation density categories. About 20% of forest and woodland cover was
lost in the 16-year analysis period, mainly due to pine and eucalyptus plantation and residential housing expansions. The
local-scale key drivers behind the deforestation are examined. 相似文献
890.
Kan-ichiro Matsumura Rover J. Hijmans Yann Chemin Christopher D. Elvidge Kenji Sugimoto Wenbin Wu Yang-won Lee Ryosuke Shibasaki 《Sustainability Science》2009,4(2):301-313
Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable
rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and
economic growth. Global patterns of rice production can be mapped by using various criteria linked to domestic income, population
patterns, and associated satellite brightness data of rice-producing regions. Prosperous regions have more electric lighting,
and there are documented correlations between gross domestic product (GDP) and nighttime light. We chose to examine global
rice production patterns on a geographical basis. For the purposes of this study, each country is considered to be made up
of regions, and rice production is discussed in terms of regional distribution. A region is delineated by its administrative
boundaries; the number of regions where rice is produced is about 13,839. We used gridded spatial population distribution
data overlain by nocturnal light imagery derived from satellite imagery. The resultant relationship revealed a correlation
between regional income (nominal values of GDP were used) and rice production in the world. The following criteria were used
to examine the supply and demand structure of rice. Global rice consumption = “caloric rice consumption per capita per day”
multiplied by “regional population values”. Regional rice yields = “country-based production” divided by “harvested area”
(multiple harvests are taken into account). Regional rice production = “regional harvested areas” multiplied by “rice yield
values”. We compared regional rice consumption and production values according to these methods. Analysis of the data sets
generated a map of rice supply and demand. Inter-regional shipping costs were not accounted for. This map can contribute to
the understanding of food security issues in rice-producing regions and to estimating potential population values in such
regions. 相似文献