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981.
John Doherty John M. Johnston 《Journal of the American Water Resources Association》2003,39(2):251-265
ABSTRACT: The use of a fitted parameter watershed model to address water quantity and quality management issues requires that it be calibrated under a wide range of hydrologic conditions. However, rarely does model calibration result in a unique parameter set. Parameter nonuniqueness can lead to predictive nonuniqueness. The extent of model predictive uncertainty should be investigated if management decisions are to be based on model projections. Using models built for four neighboring watersheds in the Neuse River Basin of North Carolina, the application of the automated parameter optimization software PEST in conjunction with the Hydrologic Simulation Program Fortran (HSPF) is demonstrated. Parameter nonuniqueness is illustrated, and a method is presented for calculating many different sets of parameters, all of which acceptably calibrate a watershed model. A regularization methodology is discussed in which models for similar watersheds can be calibrated simultaneously. Using this method, parameter differences between watershed models can be minimized while maintaining fit between model outputs and field observations. In recognition of the fact that parameter nonuniqueness and predictive uncertainty are inherent to the modeling process, PEST's nonlinear predictive analysis functionality is then used to explore the extent of model predictive uncertainty. 相似文献
982.
Jason W. Oberg Assefa M. Melesss 《Journal of the American Water Resources Association》2006,42(3):565-582
ABSTRACT: Little work is reported where spatial methods are employed to monitor evapotranspiration (ET) changes as a result of vegetation and wetland restoration. A remote sensing approach with the Surface Energy Balance Algorithm for Land (SEBAL) for estimating ET at The Nature Conservancy's Glacial Ridge prairie‐wetland restoration site in northwestern Minnesota is presented. The calibrated 24‐hour ET from SEBAL was estimated with an average error of prediction of ?4.3 percent. Monthly, interseasonal, and seasonal ET for the period of June to September (2000 to 2003) from three adjacent land‐uses: a hydrologic control preserved wetland; a treated or restored site; and a nontreated or impacted wetland, were used in the study. Results from comparing ET behavior to the preserve suggest restoration efforts have affected monthly and seasonal ET within the treated site. Spatial average standard deviations of the seasonal ET within the preserve, treated, and nontreated sites give 47.3, 75.7, and 109.9 mm, respectively, suggesting hydrologic stabilization within the treated site. Monthly and interseasonal comparisons show similar behavior to that of the seasonal data, where monthly correlations suggest increasing agreement within the treated site, approaching those within the preserve. 相似文献
983.
Alan T. Herlihy Jean Sifneos Chris Bason Amy Jacobs Mary E. Kentula M. Siobhan Fennessy 《Environmental management》2009,44(2):369-377
We sampled 92 wetlands from four different basins in the United States to quantify observer repeatability in rapid wetland
condition assessment using the Delaware Rapid Assessment Protocol (DERAP). In the Inland Bays basin of Delaware, 58 wetland
sites were sampled by multiple observers with varying levels of experience (novice to expert) following a thorough training
workshop. In the Nanticoke (Delaware/Maryland), Cuyahoga (Ohio), and John Day (Oregon) basins, 34 wetlands were sampled by
two expert teams of observers with minimal protocol training. The variance in observer to observer scoring at each site was
used to calculate pooled standard deviations (SDpool), coefficients of variation, and signal-to-noise ratios for each survey. The results showed that the experience level of
the observer had little impact on the repeatability of the final rapid assessment score. Training, however, had a large impact
on observer to observer repeatability. The SDpool in the Inland Bay survey with training (2.2 points out of a 0–30 score) was about half that observed in the other three basins
where observers had minimal training (SDpool = 4.2 points). Using the results from the survey with training, we would expect that two sites assessed by different, trained
observers who obtain DERAP scores differing by more than 4 points are highly likely to differ in ecological condition, and
that sites with scores that differ by 2 or fewer points are within variability that can be attributed to observer differences. 相似文献
984.
Snowmobile use in Yellowstone National Park has been shown to impact air quality, with implications for the safety and welfare
of Park staff and other Park resource values. Localized impacts have been documented at several high-use sites in the Park,
but the broader spatial variability of snowmobile emissions and air quality was not understood. Measurements of 87 volatile
organic compounds (VOCs) were made for ambient air sampled across the Park and West Yellowstone, Montana, during 2 days of
the 2002–2003 winter use season, 1 year before the implementation of a new snowmobile policy. The data were compared with
similar data from pristine West Coast sites at similar latitudes. Backward trajectories of local air masses, alkyl nitrate-parent
alkane ratios, and atmospheric soundings were used to identify the VOC sources and assess their impact. Different oversnow
vehicle types used in the Park were sampled to determine their relative influence on air mass pollutant composition. VOCs
were of local origin and demonstrated strong spatiotemporal variability that is primarily influenced by levels of snowmobile
traffic on given road segments at different times of day. High levels of snowmobile traffic in and around West Yellowstone
produced consistently high levels of benzene, toluene, and carbon monoxide. 相似文献
985.
William M. Adams Martin R. Perrow Angus Carpenter 《Journal of Environmental Planning and Management》2005,48(6):877-889
The restoration of river environments has been of growing importance to river management and planning in the UK. The extension of ecological restoration to floodplains as well as river channels is more complex, partly because of the range of stakeholders and the diversity of relevant management institutions. This paper draws on a qualitative survey of river managers in the UK to identify institutional factors relevant to the success or failure of floodplain restoration projects. 相似文献
986.
Estimating the Cumulative Ecological Effect of Local Scale Landscape Changes in South Florida 总被引:1,自引:0,他引:1
Hogan DM Labiosa W Pearlstine L Hallac D Strong D Hearn P Bernknopf R 《Environmental management》2012,49(2):502-515
Ecosystem restoration in south Florida is a state and national priority centered on the Everglades wetlands. However, urban
development pressures affect the restoration potential and remaining habitat functions of the natural undeveloped areas. Land
use (LU) planning often focuses at the local level, but a better understanding of the cumulative effects of small projects
at the landscape level is needed to support ecosystem restoration and preservation. The South Florida Ecosystem Portfolio
Model (SFL EPM) is a regional LU planning tool developed to help stakeholders visualize LU scenario evaluation and improve
communication about regional effects of LU decisions. One component of the SFL EPM is ecological value (EV), which is evaluated
through modeled ecological criteria related to ecosystem services using metrics for (1) biodiversity potential, (2) threatened
and endangered species, (3) rare and unique habitats, (4) landscape pattern and fragmentation, (5) water quality buffer potential,
and (6) ecological restoration potential. In this article, we demonstrate the calculation of EV using two case studies: (1)
assessing altered EV in the Biscayne Gateway area by comparing 2004 LU to potential LU in 2025 and 2050, and (2) the cumulative
impact of adding limestone mines south of Miami. Our analyses spatially convey changing regional EV resulting from conversion
of local natural and agricultural areas to urban, industrial, or extractive use. Different simulated local LU scenarios may
result in different alterations in calculated regional EV. These case studies demonstrate methods that may facilitate evaluation
of potential future LU patterns and incorporate EV into decision making. 相似文献
987.
Corace RG Shartell LM Schulte LA Brininger WL McDowell MK Kashian DM 《Environmental management》2012,49(2):359-371
To facilitate forest planning and management on National Wildlife Refuges, we synthesized multiple data sources to describe
land ownership patterns, land cover, landscape pattern, and changes in forest composition for four ecoregions and their associated
refuges of the Upper Midwest. We related observed patterns to ecological processes important for forest conservation and restoration,
with specific attention to refuge patterns of importance for forest landbirds of conservation priority. The large amount of
public land within the ecoregions (31–80%) suggests that opportunities exist for coarse and meso-scale approaches to conserving
and restoring ecological processes affecting the refuges, particularly historical fire regimes. Forests dominate both ecoregions
and refuges, but refuge forest patches are generally larger and more aggregated than in associated ecoregions. Broadleaf taxa
have increased in dominance in the ecoregions and displaced fire-dependent taxa such as pine (Pinus spp.) and other coniferous species; these changes in forest composition have likely also affected refuge forests. Despite
compositional changes, larger forest patches on refuges suggests that they may provide better habitat for area-sensitive forest
landbirds of mature, compositionally diverse forests than surrounding lands if management continues to promote increased patch
size. We reason that although fine-scale research and monitoring for species of conservation priority is important, broad
scale (ecoregional) assessments provide crucial context for effective forest and wildlife management in protected areas. 相似文献
988.
Baseline assessment for environmental services payments from satellite imagery: a case study from Costa Rica and Mexico 总被引:1,自引:0,他引:1
Kalacska M Sanchez-Azofeifa GA Rivard B Calvo-Alvarado JC Quesada M 《Journal of environmental management》2008,88(2):348-359
In this study we evaluate the accuracy of four global and regional forest cover assessments (MODIS, IGBP, GLC2000, PROARCA) as tools for baseline estimation. We conduct this research at the national scale for Costa Rica and for two tropical dry forest study sites in Costa Rica (Santa Rosa) and Mexico (Chamela-Cuixmala). We found that at the national level, the total forest cover accuracy of the four land cover maps was inflated due to an overestimation of forest in areas with an evergreen canopy. However, the four maps greatly underestimated the extent of the deciduous forest (dry forest); an ecosystem that faces high deforestation pressure and poses complications to the mapping of its extent from remotely sensed data. For the tropical dry forest sites, all maps have low forest cover accuracies (mean for Santa Rosa: 27%; mean for Chamela-Cuixmala: 56%). This has implications for policy implementation. 相似文献
989.
Convergence of Culture, Ecology, and Ethics: Management of Feral Swamp Buffalo in Northern Australia
Glenn Albrecht Clive R. McMahon David M. J. S. Bowman Corey J. A. Bradshaw 《Journal of Agricultural and Environmental Ethics》2009,22(4):361-378
This paper examines the identity of Asian swamp buffalo (Bubalus bubalis) from different value orientations. Buffalo were introduced into Northern (Top End) Australia in the early nineteenth century.
A team of transdisciplinary researchers, including an ethicist, has been engaged in field research on feral buffalo in Arnhem
Land over the past three years. Using historical documents, literature review, field observations, interviews with key informants,
and interaction with the Indigenous land owners, an understanding of the diverse views on the scientific, cultural, and economic
significance of buffalo was obtained. While the diverse stakeholders in buffalo exploitation and management have historically
delivered divergent value orientations on the nature of the human–buffalo relationship, we argue that over time there is the
possibility of values and ethical convergence. Such convergence is possible via transdisciplinary and transcultural agreement
on the value stances that constitute the construction of the being or identity of buffalo in the face of the overwhelming
need to manage population density and gross numbers. 相似文献
990.
Makadia TH Adetutu EM Simons KL Jardine D Sheppard PJ Ball AS 《Journal of environmental management》2011,92(3):866-871
We investigated the possibility of re-using remediated soils for new bioremediation projects by spiking these soils with waste oil sludge in laboratory based microcosms. The level of Total Petroleum Hydrocarbon (TPH) reduction was high (>80%) in naturally attenuated microcosms and was not significantly improved by biostimulation, bioaugmentation and the combined treatment of bioaugmentation and biostimulation by week 12. This indicated that the observed TPH reduction might have been related to the soil's inherent hydrocarbon-degrading potential. Microbial community analysis (16S rDNA and ITS-based Denaturing Gradient Gel Electrophoresis fingerprints) confirmed the dominance of hydrocarbon degrading genera such as Alcanivorax and Scedosporium. Cluster and Shannon diversity analysis revealed similar but stable bacterial and fungal communities in naturally attenuated and amended microcosms indicating that rapid reduction in TPH may not always be accompanied by changes in soil microbial communities. This study has therefore shown that soils previously used for bioremediation can have an improved hydrocarbon degrading potential which was successfully re-harnessed for new projects. This ability to re-harness this potential is attractive because it substantially reduces operational costs as no additional bioremediation treatments are needed. It can also extend a landfill's lifespan as soils can be re-used again before landfill disposal. 相似文献