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1.
William S. Fisher Leska S. Fore Leah M. Oliver Charles Lobue Robert Quarles Jed Campbell Peggy Harris Becky Hemmer Sherry Vickery Mel Parsons Aaron Hutchins Kent Bernier Danny Rodriguez Patricia Bradley 《Environmental monitoring and assessment》2014,186(11):7165-7181
States may protect coral reefs using biological water quality standards outlined by the Clean Water Act. This requires biological assessments with indicators sensitive to human disturbance and regional, probability-based survey designs. Stony coral condition was characterized on a regional scale for the first time in the nearshore waters of the US Virgin Islands (USVI). Coral composition, abundance, size, and health were assessed at 66 stations in the St. Croix region in fall 2007 and at 63 stations in the St. Thomas and St. John region in winter 2009. Indicators were chosen for their sensitivity to human disturbance. Both surveys were probability-based (random) designs with station locations preselected from areas covered by hardbottom and coral reef substrate. Taxa richness was as high as 21 species but more than half the area of both regions exhibited taxa richness of <10 species in the 25 m2 transect area. Coral density was as high as 5 colonies m?2 but more than half the area of both regions had <2 colonies m?2. Both regions showed similar dominant species based on frequency of occurrence and relative abundance. Because of large colony sizes, Montastrea annularis provided more total surface area and live surface area than more abundant species. The surveys establish baseline regional conditions and provide a foundation for long-term regional monitoring envisioned by the USVI Department of Planning and Natural Resources. The probabilistic sampling design assures the data can be used in Clean Water Act reporting. 相似文献
2.
Muthusamy Subbulakshmi Anandharaj Swetha Juliet Kumar Ponnusamy Senthil Meganathan Yogesan Vo Dai-Viet Nguyen Vaidyanathan Vinoth Kumar Muthusamy Shanmugaprakash 《Environmental Chemistry Letters》2022,20(5):3199-3234
Environmental Chemistry Letters - Most fossil fuel-derived polymers used for food packaging are non-biodegradable and induce pollution by microplastic, calling for safer material. Here we review... 相似文献
3.
Stromberg JC Lite SJ Rychener TJ Levick LR Dixon MD Watts JM 《Environmental monitoring and assessment》2006,115(1-3):145-173
A portion of Arizona’s San Pedro River is managed as a National Riparian Conservation Area but is potentially affected by ground-water withdrawals beyond the conservation area borders. We applied an assessment model to the Conservation Area as a basis for monitoring long-term changes in riparian ecosystem condition resulting from changes in river water availability, and collected multi-year data on a subset of the most sensitive bioindicators. The assessment model is based on nine vegetation bioindicators that are sensitive to changes in surface water or ground water. Site index scores allow for placement into one of three condition classes, each reflecting particular ranges for site hydrology and vegetation structure. We collected the bioindicator data at 26 sites distributed among 14 reaches that had similar stream flow hydrology (spatial flow intermittency) and geomorphology (channel sinuosity, flood-plain width). Overall, 39% of the riparian corridor fell within condition class 3 (the wettest condition), 55% in condition class 2, and 6% in the driest condition class. Condition class 3 reaches have high cover of herbaceous wetland plants (e.g., Juncus and Schoenoplectus spp.) along the perennial stream channel and dense, multi-aged Populus-Salix woodlands in the flood plain, sustained by shallow ground water in the stream alluvium. In condition class 2, intermittent stream flows result in low cover of streamside wetland herbs, but Populus-Salix remain abundant in the flood plain. Perennial wetland plants are absent from condition class 1, reflecting highly intermittent stream flows; the flood plain is vegetated by Tamarixa small tree that tolerates the deep and fluctuating ground water levels that typify this reach type. Abundance of herbaceous wetland plants and growth rate of Salix gooddingii varied between years with different stream flow rates, indicating utility of these measures for tracking short-term responses to hydrologic change. Repeat measurement of all bioindicators will indicate long-term trends in hydro-vegetational condition. 相似文献
4.
Isolated Spring Wetlands in the Great Basin and Mojave Deserts,USA: Potential Response of Vegetation to Groundwater Withdrawal 总被引:3,自引:0,他引:3
Desert springs, often the sole sources of water for wildlife and cattle, support wetland and wetland/upland transition ecosystems
including rare and endemic species. In the basin and range province in Nevada, USA, springs in the Great Basin and Mojave
deserts are sustained by interconnected deep carbonate and shallow basin-fill aquifers which are threatened by proposed groundwater
withdrawal to sustain rapidly expanding urban areas, a common problem in arid regions worldwide. This paper draws on historic
groundwater data, groundwater modeling, and studies of environmental controls of spring ecosystems to speculate on the potential
effects of groundwater withdrawal and water table decline on spring-supported vegetation. The focus is on springs in the Great
Basin and Mojave deserts representative of those that may be affected by future, planned groundwater withdrawal. Groundwater
withdrawal is expected to reduce spring discharge directly through reduced flows from the shallow basin-fill aquifer or through
reduction of the hydraulic head of the deep carbonate aquifer. This flow reduction will truncate the outflow stream, reducing
the areal cover of wetland and wetland/upland transition vegetation. Lowering the local water table may also reduce the amount
of upland phreatophytic vegetation by causing water levels to drop below plant rooting depths. Percolation of salts to surface
soils may be reduced, eventually altering desert shrub cover from halophytes to nonhalophytes. The extent of these effects
will vary among springs, based on their distance from extraction sites and location relative to regional groundwater flow
paths. On-site monitoring of biotic variables (including cover of selected hygrophytes and phreatophytes) should be a necessary
complement to the planned monitoring of local hydrologic conditions. 相似文献
5.
Community involvement is fundamental to the management of multijurisdictional river basins but, in practice, is very difficult
to achieve. The Murray-Darling basin, in Australia, and the Mekong River basin in Southeast Asia are both cooperatively managed
multijurisdictional river basins where the management authorities have expressed an aim of community involvement. In the Murray-Darling
basin vigorous efforts have promoted a culture of community consultation throughout each of the state jurisdictions involved,
although true participation has not necessarily been achieved. In the Mekong basin the community is much more diverse and
the successes so far have been largely at the local level, involving action in subsections of the basin. These case studies
suggest that community involvement in the form of community consultation across large multijurisdictional river basins is
achievable, but more comprehensive participation is not necessarily possible. 相似文献
6.
Michael Ackah Alfred Kwablah Anim Eva Tabuaa Gyamfi Nafisatu Zakaria John Hanson Delali Tulasi Sheriff Enti-Brown Esther Saah-Nyarko Nash Owusu Bentil Juliet Osei 《Environmental monitoring and assessment》2014,186(1):621-634
The heavy metals (Fe, Zn, Pb, Ni, Cr, Co, and Cd) burden in wastewater, soil, and vegetable samples from a wastewater irrigated farm located at KorleBu, Accra has been investigated. Flame atomic absorption spectrometry after microwave digestion using a combination of HNO3, HCl, and H2O2 (for water), and HNO3 and HCl (for soil and vegetables). The mean concentrations (in milligrams per kilogram) of heavy metals in the soil samples were in the order of Fe (171?±?5.22)?>?Zn (36.06?±?4.54)?>?Pb (33.35?±?35.62)?>?Ni (6.31?±?8.15)?>?Cr (3.40?±?3.63)?>?Co (1.36?±?0.31)?>?Cd (0.43?±?0.24), while the vegetables were in the order of Fe (183.11?±?161.2)?>?Zn (5.38?±?3.50)?>?Ni (3.52?±?1.27)?>?Pb (2.49?±?1.81)?>?Cr (1.46?±?0.51)?>?Co (0.66?±?0.25)?>?Cd (0.36?±?0.15). The bioconcentration factors suggest environmental monitoring for the heavy metals as follows: Cd (0.828), Cr (0.431), Ni (0.558), Co (0.485), and Fe (1.067). Estimated daily intakes were very low for both children and adults except Fe (0.767 mg/kg/day) in children. The population that consume vegetables from the study area were, however, estimated to be safe based on the results obtained from the health risk index, which were all?<?<1. The sodium absorption ratio according to FAO (1985) classifications indicate that the wastewater in the study area is unsuitable for irrigation purposes. 相似文献
7.
Robert L. Getty Juliet Getty 《International journal of occupational safety and ergonomics》2013,19(2):161-194
AbstractA holistic view is essential for quality initiatives such as Total Quality Management (TQM), Standard No. ISO 9001:1994 (International Organization for Standardization [ISO], 1994), Concurrent Engineering, Business Reengineering, and Business Process Improvement. The challenge is knowing how to transition from this theoretical concept to implementation. The relationship between quality interest and anergonomics program will be the focus of this discussion. An ergonomics oriented improvement program includes (a) ergonomics or fitting the job to the person; (b) integration of operations management, safety engineering, medical management, and employees as co-owners of the process; (c) the emphasis of ergonomic precepts in the engineering of new processes and improvement of current processes; and (d) the emphasis of employees taking responsibility for their own well being and the improvement of their work environment. The parallel between the continuous improvement process delineated by the quality-system requirements in Standard No. ISO 9001:1994 (ISO, 1994) and the improvement contributions of ergonomics are very revealing (Getty, Abbott, & Getty, 1995). It is the contention of this approach that if the precepts of ergonomics were applied to the work environment, it would support the objective of world class quality and productivity, resulting in improved global competitiveness of businesses. 相似文献
8.
Models of parasite-mediated sexual selection have thus far overlooked the potential effects of parasites of females on their
hosts’ ability to choose mates. A set of models addressing this issue is developed, each building on the previous one to add
complexity and realism to the framework. The selection coefficient for parasite immunity and brightness is estimated using
the ratio of the fitness of susceptible males to the fitness of immune males. Parasite-induced reduction in female choosiness
can substantially relax the selection for bright, immune males, especially when: (1) immunity to parasites is rare in the
population, (2) parasites are not highly aggregated within the host population, (3) parasites are abundant, and (4) the effects
of parasites on male brightness or female choosiness are severe. Parasite-induced variability in male brightness is most likely
to occur in populations in which parasites are abundant and not aggregated; if females in those populations show a reduced
preference for bright males, sexual selection for brightness (and parasite immunity) will still operate but exert a weaker
selective pressure.
Received: 4 November 1994/Accepted after revision: 9 September 1995 相似文献
9.
Sorrel Jones Sarah Papworth Aidan M. Keane Juliet Vickery Freya A. V. St John 《Conservation biology》2021,35(2):722-732
Conservationists need to measure human behavior to guide decisions and evaluate their impact. However, activities can be misreported and reporting accuracy may change following conservation interventions, making it hard to verify any apparent changes. Techniques for asking sensitive questions are increasingly integrated into survey designs to improve data quality, but some can be costly or hard for nonexperts to implement. We demonstrate a straightforward, low-cost approach, the bean method in which respondents give anonymous answers by adding a colored bean to a jar to denote a yes or no response. We applied the bean method to measure wild-meat hunting and trading over 2 years at a conservation-project (hunting reduction) site in Gola Forest, Liberia. We extended the technique to accommodate questions about hunting and meat-selling frequency. We compared responses given using the bean method and direct questioning for groups that did and did not participate in conservation interventions. Results from the bean method corresponded to those from direct questioning, and there was no indication of change in question sensitivity following conservation interventions. Estimates from both methods indicated that wild-meat trading decreased in project and nonproject households (from 36% to 20%) and that hunting decreased in 1 project group (38–28%). Where inconsistent answers were given (2–6% of respondents), differences were in both directions and were most likely attributable to measurement error. The bean method was quick and straightforward to administer in a low-literacy setting. We showed how it can be modified for answers of more than 2 categories and consider it a valuable tool that could be adapted for a wide range of conservation settings. 相似文献
10.
Alain Houle Colin A. Chapman William L. Vickery 《Behavioral ecology and sociobiology》2010,64(3):429-441
Recently, we demonstrated that the highest densities of fruit pulp are located in the uppermost zones of tree crowns. Since
heterogeneous distributions of depletable food is theorized to foster contest competition, we tested three hypotheses involving
rank differences among species of arboreal frugivores: (1) In the absence of competitors, species tend to feed in higher strata
of tree crowns; (2) interspecific contest competition occurs through monopolization and usurpation of feeding sites in these
higher strata; and (3) subordinate species decrease their feeding height and ingestion rate when dominants enter the food
patch. To test these hypotheses, we observed chimpanzees (Pan troglodytes), red-tailed monkeys (Cercopithecus ascanius), blue monkeys (Cercopithecus mitis), and gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We found that: (1) all four primates fed preferentially in upper tree crowns when alone,
(2) dominant species monopolized and aggressively usurped the upper crown when co-feeding with subordinates and the latter
retreated below the middle of tree crowns, (3) in the presence of dominant species, subordinate species showed lower standardized
feeding height and modified their food intake rates, while dominants were not affected by the subordinate species, (4) subordinates
moved down at the arrival of and up at the departure of dominants, and (5) the presence of folivores in the tree did not affect
the feeding height of a frugivore, even through folivores were socially dominant. Contrary to expectations, we found that
red-tailed monkeys decreased their movements between successive fruits that they ate in the presence of blue monkeys compared
to when they were feeding alone, perhaps to avoid disturbing dominants and attracting aggression or because they ingested
more semi-ripe and green unripe fruits, i.e., more food of lower quality. 相似文献