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141.
Poudyal NC Johnson-Gaither C Goodrick S Bowker JM Gan J 《Environmental management》2012,49(3):623-635
Wildland fire in the South commands considerable attention, given the expanding wildland urban interface (WUI) across the
region. Much of this growth is propelled by higher income retirees and others desiring natural amenity residential settings.
However, population growth in the WUI increases the likelihood of wildfire fire ignition caused by people, as humans account
for 93% of all wildfires fires in the South. Coexisting with newly arrived, affluent WUI populations are working class, poor
or otherwise socially vulnerable populations. The latter groups typically experience greater losses from environmental disasters
such as wildfire because lower income residents are less likely to have established mitigation programs in place to help absorb
loss. We use geographically weighted regression to examine spatial variation in the association between social vulnerability
(SOVUL) and wildfire risk. In doing so, we identify “hot spots” or geographical clusters where SOVUL varies positively with
wildfire risk across six Southern states—Alabama, Arkansas, Florida, Georgia, Mississippi, and South Carolina. These clusters
may or may not be located in the WUI. These hot spots are most prevalent in South Carolina and Florida. Identification of
these population clusters can aid wildfire managers in deciding which communities to prioritize for mitigation programming. 相似文献
142.
Bellmore JR Baxter CV Ray AM Denny L Tardy K Galloway E 《Environmental management》2012,49(3):734-750
Pre-restoration studies typically focus on physical habitat, rather than the food-base that supports aquatic species. However,
both food and habitat are necessary to support the species that habitat restoration is frequently aimed at recovering. Here
we evaluate if and how the productivity of the food-base that supports fish production is impaired in a dredge-mined floodplain
within the Yankee Fork Salmon River (YFSR), Idaho (USA); a site where past restoration has occurred and where more has been
proposed to help recover anadromous salmonids. Utilizing an ecosystem approach, we found that the dredged segment had comparable
terrestrial leaf and invertebrate inputs, aquatic primary producer biomass, and production of aquatic invertebrates relative
to five reference floodplains. Thus, the food-base in the dredged segment did not necessarily appear impaired. On the other
hand, we observed that off-channel aquatic habitats were frequently important to productivity in reference floodplains, and
the connection of these habitats in the dredged segment via previous restoration increased invertebrate productivity by 58%.
However, using a simple bioenergetic model, we estimated that the invertebrate food-base was at least 4× larger than present
demand for food by fish in dredged and reference segments. In the context of salmon recovery efforts, this observation questions
whether additional food-base productivity provided by further habitat restoration would be warranted in the YFSR. Together,
our findings highlight the importance of studies that assess the aquatic food-base, and emphasize the need for more robust
ecosystem models that evaluate factors potentially limiting fish populations that are the target of restoration. 相似文献
143.
Temporal and spatial vegetation structure has impact on biodiversity qualities. Yet, current schemes of biotope mapping do
only to a limited extend incorporate these factors in the mapping. The purpose of this study is to evaluate the application
of a modified biotope mapping scheme that includes temporal and spatial vegetation structure. A refined scheme was developed
based on a biotope classification, and applied to a green structure system in Helsingborg city in southern Sweden. It includes
four parameters of vegetation structure: continuity of forest cover, age of dominant trees, horizontal structure, and vertical
structure. The major green structure sites were determined by interpretation of panchromatic aerial photographs assisted with
a field survey. A set of biotope maps was constructed on the basis of each level of modified classification. An evaluation
of the scheme included two aspects in particular: comparison of species richness between long-continuity and short-continuity
forests based on identification of woodland continuity using ancient woodland indicators (AWI) species and related historical
documents, and spatial distribution of animals in the green space in relation to vegetation structure. The results indicate
that (1) the relationship between forest continuity: according to verification of historical documents, the richness of AWI
species was higher in long-continuity forests; Simpson’s diversity was significantly different between long- and short-continuity
forests; the total species richness and Shannon’s diversity were much higher in long-continuity forests shown a very significant
difference. (2) The spatial vegetation structure and age of stands influence the richness and abundance of the avian fauna
and rabbits, and distance to the nearest tree and shrub was a strong determinant of presence for these animal groups. It is
concluded that continuity of forest cover, age of dominant trees, horizontal and vertical structures of vegetation should
now be included in urban biotope classifications. 相似文献
144.
Naser?A.?Anjum Iqbal?AhmadEmail author Mónica?Válega Etelvina?Figueira Armando?C.?Duarte Eduarda?Pereira 《Environmental science and pollution research international》2013,20(6):3910-3922
Efficient and sustainable management of rapidly mounting environmental issues has been the focus of current intensive research. The present study aimed to investigate the impact of plant phenological development stage variation on mercury (Hg) tolerance, accumulation, and allocation in two salt marsh macrophytes Triglochin maritima and Scirpus maritimus prevalent in historically Hg-contaminated Ria de Aveiro coastal lagoon (Portugal). Both plant samples and the sediments vegetated by monospecific stands of T. maritima and S. maritimus were collected from reference (R) and sites with moderate (M) and high (H) Hg contamination in Laranjo bay within Ria de Aveiro lagoon. Hg tolerance, uptake, and allocation in T. maritima and S. maritimus, physico-chemical traits (pH, redox potential, and organic matter content) and Hg concentrations in sediments vegetated by these species were impacted differentially by phenological development stages variation irrespective of the Hg contamination level. In T. maritima, Hg concentration increased with increase in Hg contamination gradient where root displayed significantly higher Hg followed by rhizome and leaf maximally at H. However, in S. maritimus, the highest Hg concentration was perceptible in rhizome followed by root maximally at M. Between the two studied plant species, S. maritimus displayed higher Hg tolerance index (depicted by higher plant dry mass allocated to reproductive stage) and higher available Hg at M (during all growth stages) and H (during senescent stage) when compared to T. maritimus. Both plant species proved to be Hg excluder (low root/rhizome–leaf Hg translocation). Additionally, T. maritima also acted as Hg stabilizer while, S. maritimus as Hg accumulator. It can be inferred from the study that (a) the plant phenological development stage variations significantly influenced plant Hg sensitivity by impacting sediment chemistry, plant growth (in terms of plant dry mass), Hg accumulation, and its subsequent allocation capacity, contingent to Hg contamination gradient; (b) S. maritimus accumulated higher Hg but restricted its translocation to above-ground part using exclusion process at both M and H due to its accelerated growth during Hg-tolerant reproductive/metabolically active phenological development stage greater than its counterpart T. maritima; and (c) the studied salt marsh plants although hailed from the same C3 and monocot group did not necessarily display similar phenotypic plasticity and behavior towards Hg-contaminated scenario during their life cycle. 相似文献
145.
Bordeleau G Savard MM Martel R Ampleman G Thiboutot S 《Journal of contaminant hydrology》2008,98(3-4):97-105
Nitrate is one of the most common contaminants in shallow groundwater, and many sources may contribute to the nitrate load within an aquifer. Groundwater nitrate plumes have been detected at several ammunition production sites. However, the presence of multiple potential sources and the lack of existing isotopic data concerning explosive degradation-induced nitrate constitute a limitation when it comes to linking both types of contaminants. On military training ranges, high nitrate concentrations in groundwater were reported for the first time as part of the hydrogeological characterization of the Cold Lake Air Weapons Range (CLAWR), Alberta, Canada. Explosives degradation is thought to be the main source of nitrate contamination at CLAWR, as no other major source is present. Isotopic analyses of N and O in nitrate were performed on groundwater samples from the unconfined and confined aquifers; the dual isotopic analysis approach was used in order to increase the chances of identifying the source of nitrate. The isotopic ratios for the groundwater samples with low nitrate concentration suggested a natural origin with a strong contribution of anthropogenic atmospheric NOx. For the samples with nitrate concentration above the expected background level the isotopic ratios did not correspond to any source documented in the literature. Dissolved RDX samples were degraded in the laboratory and results showed that all reproduced degradation processes released nitrate with a strong fractionation. Laboratory isotopic values for RDX-derived NO(3)(-) produced a trend of high delta(18)O-low delta(15)N to low delta(18)O-high delta(15)N, and groundwater samples with nitrate concentrations above the expected background level appeared along this trend. Our results thus point toward a characteristic field of isotopic ratios for nitrate being derived from the degradation of RDX. 相似文献
146.
Helena M?kinen Kalevi Nieminen Susanna M?ki Sirkku Siiskonen 《International journal of occupational safety and ergonomics》2008,14(1):19-28
High temperature alkaline chemical liquids have caused injuries and hazardous situations in Finnish pulp manufacturing mills. There are no requirements and/or test method standards concerning protection against high temperature alkaline chemical splashes. This paper describes the test method development process to test and identify materials appropriate for hot liquid chemical hazard protection. In the first phase, the liquid was spilled through a stainless steel funnel and the protection performance was evaluated using a polyvinyl chloride (PVC) film under the test material. After several tentative improvements, a graphite crucible was used for heating and spilling the chemical, and a copper-coated K-type thermometer with 4 independent measuring areas was designed to measure the temperature under the material samples. The thermometer was designed to respond quickly so that peak temperatures could be measured. The main problem was to keep the spilled amount of chemical constant, which unfortunately resulted in significant variability in data. 相似文献
147.
Yasundo?KurataEmail author Yusaku?Ono Yoshiro?Ono 《Journal of Material Cycles and Waste Management》2008,10(2):144-152
The concentrations of 41 phenols in leachates from 38 municipal solid waste (MSW) landfill sites in Japan were measured. The
main phenols detected in leachates were phenol, three cresols, 4-tert-butylphenol, 4-tertoctylphenol, 4-nonylphenol, bisphenol
A, and some chlorophenols. The concentration levels of phenols were affected by the pH values of the leachates and the different
types of landfill waste. The origins of phenol and p-cresol were considered to be incineration residues, and the major origin of 4-tert-butylphenol, bisphenol A, and 2,4,6-trichlorophenol
was considered to be solidified fly ash. In contrast, the major origins of 4-tert-octylphenol and 4-nonylphenol were considered
to be incombustibles. The discharge of leachates to the environment around MSW landfill sites without water treatment facilities
can cause environmental pollution by phenols. In particular, the disposal of incineration residues including solidified fly
ash and the codisposal of solidified fly ash and incombustibles might raise the possibility of environmental pollution. Moreover,
the discharge of leachates at pH values of 9.8 or more could pollute the water environment with phenol. However, phenol, 4-nonylphenol,
and bisphenol A can be removed to below the con centration levels that impact the environment around landfill sites by a series
of conventional water treatment processes. 相似文献
148.
149.
The concentrations of heavy metals and metals (Zn, Pb, Bi, Cd, Ni, Co, Fe, Mn, Mg, Cu, Cr, Ca, Sr, Na, Li, K) were measured in muscle of five species Cyprinus carpio (from I??kl? dam), Scardinius erythrophthalmus (from I??kl? dam), Tinca tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), Carassius carassius (from Karaca?ren dam) caught from I??kl? and Karaca?ren. The highest metal was Na (466.95 μg/g) in C. carassius, while the lowest levels were Fe (0.37 μg/g) and Cu (0.37 μg/g) in C. carpio from I??kl? dam. The mean concentrations μg/g d.w. some of heavy metals in muscle of C. carpio (from I??kl? dam), S. erythrophthalmus (from I??kl? dam), T. tinca (from I??kl? dam), C. carpio (from Karaca?ren dam), C. carassius (from Karaca?ren dam) were as follows: Cd 2.00-2.10-1.95-2.06-2.27, Zn 4.36-2.64-13.13-13.33-24.47, Pb 1.65-1.24-1.90-2.37-2.41, Co 2.46-2.37-2.48-2.58-2.80, Mg 138.51-154.35-218.59-204.58-202.16, Fe 0.37-2.62-3.17-3.01-12.33, respectively. 相似文献
150.
Jürgens N Schmiedel U Haarmeyer DH Dengler J Finckh M Goetze D Gröngröft A Hahn K Koulibaly A Luther-Mosebach J Muche G Oldeland J Petersen A Porembski S Rutherford MC Schmidt M Sinsin B Strohbach BJ Thiombiano A Wittig R Zizka G 《Environmental monitoring and assessment》2012,184(2):655-678
The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects. 相似文献