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751.
Lior Davidovitch Richard Stoklosa Jonathan Majer Alex Nietrzeba Peter Whittle Kerrie Mengersen Yakov Ben-Haim 《Journal of environmental management》2009
Surveillance for invasive non-indigenous species (NIS) is an integral part of a quarantine system. Estimating the efficiency of a surveillance strategy relies on many uncertain parameters estimated by experts, such as the efficiency of its components in face of the specific NIS, the ability of the NIS to inhabit different environments, and so on. Due to the importance of detecting an invasive NIS within a critical period of time, it is crucial that these uncertainties be accounted for in the design of the surveillance system. We formulate a detection model that takes into account, in addition to structured sampling for incursive NIS, incidental detection by untrained workers. We use info-gap theory for satisficing (not minimizing) the probability of detection, while at the same time maximizing the robustness to uncertainty. We demonstrate the trade-off between robustness to uncertainty, and an increase in the required probability of detection. An empirical example based on the detection of Pheidole megacephala on Barrow Island demonstrates the use of info-gap analysis to select a surveillance strategy. 相似文献
752.
Baer SG Engle DM Knops JM Langeland KA Maxwell BD Menalled FD Symstad AJ 《Environmental management》2009,43(2):189-196
Vast areas of arable land have been retired from crop production and “rehabilitated” to improved system states through landowner
incentive programs in the United States (e.g., Conservation and Wetland Reserve Programs), as well as Europe (i.e., Agri-Environment
Schemes). Our review of studies conducted on invasion of rehabilitated agricultural production systems by nontarget species
elucidates several factors that may increase the vulnerability of these systems to invasion. These systems often exist in
highly fragmented and agriculturally dominated landscapes, where propagule sources of target species for colonization may
be limited, and are established under conditions where legacies of past disturbance persist and prevent target species from
persisting. Furthermore, rehabilitation approaches often do not include or successfully attain all target species or historical
ecological processes (e.g., hydrology, grazing, and/or fire cycles) key to resisting invasion. Uncertainty surrounds ways
in which nontarget species may compromise long term goals of improving biodiversity and ecosystem services through rehabilitation
efforts on former agricultural production lands. This review demonstrates that more studies are needed on the extent and ecological
impacts of nontarget species as related to the goals of rehabilitation efforts to secure current and future environmental
benefits arising from this widespread conservation practice. 相似文献
753.
Allen CD 《Environmental management》2009,43(2):346-356
Characterized by expensive housing, high socioeconomic status, and topographic relief, Upper Sonoran Lifestyle communities
are found primarily along the Wildland-Urban Interface (WUI) in the Phoenix, Arizona metro area. Communities like these sprawl
into the wildlands in the United States Southwest, creating a distinct urban fringe. This article, through locational comparison,
introduces and evaluates a new field assessment tool for monitoring anthropogenic impact on soil–vegetation interactions along
the well-maintained multi-use recreational trails in Upper Sonoran Lifestyle region. Comparing data from randomly selected
transects along other multi-use trails with data from a control site revealed three key indicators of anthropogenic disturbances
on soil–vegetation interactions: soil disturbance, vegetation disturbance, and vegetation density. Soil and vegetation disturbance
displayed an average distance decay exponent factor of −0.60, while vegetation density displayed a reverse decay average of
0.60. Other important indicators of disturbance included vegetation type, biological soil crusts, and soil bulk density. The
predictive ability of this new field tool enhances its applicability, offering a powerful rapid ecological assessment method
for monitoring long-term anthropogenic impact in the Upper Sonoran Lifestyle, and other sprawling cities along the WUI. 相似文献
754.
Benjamin M. Jones Christopher D. Arp Kenneth M. Hinkel Richard A. Beck Joel A. Schmutz Barry Winston 《Environmental management》2009,43(6):1071-1084
Lakes are dominant landforms in the National Petroleum Reserve Alaska (NPRA) as well as important social and ecological resources.
Of recent importance is the management of these freshwater ecosystems because lakes deeper than maximum ice thickness provide
an important and often sole source of liquid water for aquatic biota, villages, and industry during winter. To better understand
seasonal and annual hydrodynamics in the context of lake morphometry, we analyzed lakes in two adjacent areas where winter
water use is expected to increase in the near future because of industrial expansion. Landsat Thematic Mapper and Enhanced
Thematic Mapper Plus imagery acquired between 1985 and 2007 were analyzed and compared with climate data to understand interannual
variability. Measured changes in lake area extent varied by 0.6% and were significantly correlated to total precipitation
in the preceding 12 months (p < 0.05). Using this relation, the modeled lake area extent from 1985 to 2007 showed no long-term trends. In addition, high-resolution
aerial photography, bathymetric surveys, water-level monitoring, and lake-ice thickness measurements and growth models were
used to better understand seasonal hydrodynamics, surface area-to-volume relations, winter water availability, and more permanent
changes related to geomorphic change. Together, these results describe how lakes vary seasonally and annually in two critical
areas of the NPRA and provide simple models to help better predict variation in lake-water supply. Our findings suggest that
both overestimation and underestimation of actual available winter water volume may occur regularly, and this understanding
may help better inform management strategies as future resource use expands in the NPRA. 相似文献
755.
Michael D. Kaplowitz Felix K. Yeboah Laurie Thorp Aimee M. Wilson 《Resources, Conservation and Recycling》2009,53(11):612-623
With increasing environmental challenges confronting our planet, colleges and universities are trying different approaches for minimizing their adverse environmental impacts. Among the approaches being used to revitalize campus sustainability efforts, new waste management strategies have included attempts to improve campus-recycling programs. This paper presents select findings from a comprehensive study at a large, Tier I university aimed at, among other things, informing university administration and decision makers working on the planning and implementation of a new campus-wide recycling facility and program. The researchers used a mixed-method approach to help them develop an understanding of the campus community's (1) perceived barriers to recycling, (2) recycling knowledge, (3) program preferences, and (4) environmental attitudes. The results from a web-based survey (n = 3896, RR1 = 24.9%) suggest, communication efforts for recycling programming should focus more on messages concerning what, how, and where to recycle rather than messages on why to recycle. Furthermore, the results suggest recycling-related publicity approaches should differentiate their mode and content for different segments of the community. 相似文献
756.
Itziar de Aranzabal María F. Schmitz Francisco D. Pineda 《Environmental management》2009,44(5):938-951
Tourism and landscape are interdependent concepts. Nature- and culture-based tourism are now quite well developed activities
and can constitute an excellent way of exploiting the natural resources of certain areas, and should therefore be considered
as key objectives in landscape planning and management in a growing number of countries. All of this calls for careful evaluation
of the effects of tourism on the territory. This article focuses on an integrated spatial method for landscape analysis aimed
at quantifying the relationship between preferences of visitors and landscape features. The spatial expression of the model
relating types of leisure and recreational preferences to the potential capacity of the landscape to meet them involves a
set of maps showing degrees of potential visitor satisfaction. The method constitutes a useful tool for the design of tourism
planning and management strategies, with landscape conservation as a reference. 相似文献
757.
J. Juri Ayub D.E. Di Gregorio H. Velasco H. Huck M. Rizzotto F. Lohaiza 《Journal of environmental radioactivity》2009
The 7Be wet deposition has been intensively investigated in a semiarid region at San Luis Province, Argentina. From November 2006 to May 2008, the 7Be content in rainwater was determined in 58 individual rain events, randomly comprising more than 50% of all individual precipitations at the sampling period. 7Be activity concentration in rainwater ranged from 0.7 ± 0.3 Bq l−1 to 3.2 ± 0.7 Bq l−1, with a mean value of 1.7 Bq l−1 (sd = 0.53 Bq l−1). No relationship was found between 7Be content in rainwater and (a) rainfall amount, (b) precipitation intensity and (c) elapsed time between events. 7Be ground deposition was found to be well correlated with rainfall amount (R = 0.92). For the precipitation events considered, the 7Be depositional fluxes ranged from 1.1 to 120 Bq m−2, with a mean value of 32.7 Bq m−2 (sd = 29.9 Bq m−2). The annual depositional flux was estimated at 1140 ± 120 Bq m−2 y−1. Assuming the same monthly deposition pattern and that the 7Be content in soil decreases only through radioactive decay, the seasonal variation of 7Be areal activity density in soil was estimated. Results of this investigation may contribute to a valuable characterization of 7Be input in the explored semiarid ecosystem and its potential use as tracer of environmental processes. 相似文献
758.
L. León Vintró P.I. Mitchell A. Omarova M. Burkitbayev H. Jiménez Nápoles N.D. Priest 《Journal of environmental radioactivity》2009
New data are reported on the concentrations, isotopic composition and speciation of americium, plutonium and uranium in surface and ground waters in the Sarzhal region of the Semipalatinsk Test Site, and an adjacent area including the settlement of Sarzhal. The data relate to filtered water and suspended particulate from (a) streams originating in the Degelen Mountains, (b) the Tel′kem 1 and Tel′kem 2 atomic craters, and (c) wells on farms located within the study area and at Sarzhal. The measurements show that 241Am, 239,240Pu and 238U concentrations in well waters within the study area are in the range 0.04–87 mBq dm−3, 0.7–99 mBq dm−3, and 74–213 mBq dm−3, respectively, and for 241Am and 239,240Pu are elevated above the levels expected solely on the basis of global fallout. Concentrations in streams sourced in the Degelen Mountains are similar, while concentrations in the two water-filled atomic craters are somewhat higher. Suspended particulate concentrations in well waters vary considerably, though median values are very low, at 0.01 mBq dm−3, 0.08 mBq dm−3 and 0.32 mBq dm−3 for 241Am, 239,240Pu and 238U, respectively. The 235U/238U isotopic ratio in almost all well and stream waters is slightly elevated above the ‘best estimate’ value for natural uranium worldwide, suggesting that some of the uranium in these waters is of test-site provenance. Redox analysis shows that on average most of the plutonium present in the microfiltered fraction of these waters is in a chemically reduced form (mean 69%; 95% confidence interval 53–85%). In the case of the atomic craters, the proportion is even higher. As expected, all of the americium present appears to be in a reduced form. Calculations suggest that annual committed effective doses to individual adults arising from the daily ingestion of these well waters are in the range 11–42 μSv (mean 21 μSv). Presently, the ground water feeding these wells would not appear to be contaminated with radioactivity from past underground testing in the Degelen Mountains or from the Tel′kem explosions. 相似文献
759.
Robert Kase Peter D. Hansen Birgit Fischer Werner Manz Peter Heininger Georg Reifferscheid 《Environmental science and pollution research international》2009,16(1):54-64
Background, aim, and scope The enzyme-linked receptor assay (ELRA) detects estrogenic and anti-estrogenic effects at the molecular level of receptor
binding and is a useful tool for the integrative assessment of ecotoxicological potentials caused by hormonally active agents
(HAA) and endocrine disrupting compounds (EDC). The main advantage of the ELRA is its high sample throughput and its robustness
against cytotoxicity and microbial contamination. After a methodological adaptation to salinity of the ELRA, according to
the first part of this study, which increased its salinity tolerance and sensitivity for 17-β-estradiol, the optimised ELRA
was used to investigate 13 native sediments characterised by different levels of salinity and chemical contamination. The
applicability of the ELRA for routine analysis in environmental assessment was evaluated. Salinity is often a critical factor
for bioassays in ecotoxicological sediment assessment. Therefore, salinity of the samples was additionally adjusted to different
levels to characterise its influence on elution and binding processes of receptor-binding substances.
Materials and methods The ELRA was carried out with the human estrogen receptor α (ER) in a 96-well microplate format using the experimental setup
known from the competitive immunoassay based on ligand–protein interaction. It is an important improvement that a physiologically
relevant receptor was used as a linking protein instead of an antibody. The microplates were coated with a 17-β-estradiol-BSA
conjugate, and dilution series of estradiol and of native sediment samples were added and incubated with the ER. After a washing
step, a biotinylated mouse anti-ER antibody was added to each well. Receptor binding to estradiol, agonistic and antagonistic
receptor binding, were determined by a streptavidin-POD-biotin complex with subsequent measurement of the peroxidase activity
at the wavelength of 450 nm using a commercial ELISA multiplate reader. The sediment elutriates and pore water samples of
sediments were tested in a dilution series to evaluate at which dilution step the receptor-binding potential ends. In the
elution process (see Section 2.1 to 2.2), a method was developed to adjust the salinity to the levels of the reference testings, which offers an appropriate option
to adjust the salinity in both directions. Statistical evaluation was made with a combination of the Mann–Whitney U test and the pT-method.
Results This part of the study characterised the environmental factor ‘salinity’ for prospective applications of the ELRA. Using reference
substances such as 17-β-estradiol, the ELRA showed sigmoid concentration-effect relations over a broad range from 0.05 μg/l
to 100 μg/l under physiological conditions. After methodological optimisation, both sensitivity and tolerance of the assay
against salinity could be significantly raised, and the ELRA became applicable under salinity conditions up to concentrations
of 20.5‰. The mean relative inter-test error (n = 3) was around 11% with reference substances and below 5% for single sediments elutriates in three replicates each. For
sediment testings, the pore water and different salinity-adjusted elutriates of 13 sediments were used. A clear differentiation
of the receptor-binding potential could be reached by application of the pT-method. Thereby, pT-values from one to six could
be assigned to the sediments, and the deviation caused by the different salinity conditions was one pT-value. The mean standard
deviation in the salinity adaptation procedure of the elutriates was below 5%.
Discussion Although the ELRA has already been used for assessments of wastewater, sludge and soil, its applicability for samples to different
salinity levels has not been investigated so far. Even if the ELRA is not as sensitive as the E-screen or the YES-assay, with
regard to reference substances like 17-β-estradiol, it is a very useful tool for pre-screening, because it is able to integrate
both estrogenic as well as anti-estrogenic receptor-binding effects. According to the results of sediment testing, and given
the integrative power to detect different directions of effects, the ELRA shows sufficient sensitivity and salinity tolerance
to discriminate receptor-binding potentials in environmental samples.
Conclusions The optimised ELRA assay is a fast, cost-effective, reliable and highly reproducible tool that can be used for high-throughput
screening in a microplate format in detecting both estrogenic and anti-estrogenic effects. Additionally, the ELRA is robust
against microbial contaminations, and is not susceptible towards cytotoxic interferences like the common cell-culture methods.
The general applicability and sufficient sensitivity of the ELRA was shown in freshwater environments. Marine and brackish
samples can be measured up to salinity levels of 20.5‰.
Recommendations and perspectives In view of the proven sensitivity, functionality and the fastness of the ELRA, it is recommendable to standardise the test
method. At the moment, no adequate in vitro test procedure exists which is standardised to DIN or ISO levels. The E-screen
and the yeast estrogen/androgen screens (YES/YAS) sometimes underlie strong cytotoxic effects, as reported in the first part
of this study. Further development of an ELRA assay using human androgen receptors appears to be very promising to gain information
about androgenic and anti-androgenic effects, too. This would offer a possibility to use the ELRA as a fast and reliable pre-screening
tool for the detection of endocrine potentials, thus minimising time and cost-expensive animal experiments. 相似文献
760.