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61.
Nina Rønsted Seana K. Walsh Margaret Clark Merlin Edmonds Tim Flynn Scott Heintzman Alexander Loomis David Lorence Uma Nagendra Ben Nyberg Michael Opgenorth Lauren Weisenberger Adam Williams Dustin Wolkis Kenneth R. Wood Matthew Keir 《Conservation biology》2022,36(4):e13896
The International Union for Conservation of Nature's Red List of Threatened Species (IUCN Red List) is the world's most comprehensive information source on the global conservation status of species. Governmental agencies and conservation organizations increasingly rely on IUCN Red List assessments to develop conservation policies and priorities. Funding agencies use the assessments as evaluation criteria, and researchers use meta-analysis of red-list data to address fundamental and applied conservation science questions. However, the circa 143,000 IUCN assessments represent a fraction of the world's biodiversity and are biased in regional and organismal coverage. These biases may affect conservation priorities, funding, and uses of these data to understand global patterns. Isolated oceanic islands are characterized by high endemicity, but the unique biodiversity of many islands is experiencing high extinction rates. The archipelago of Hawaii has one of the highest levels of endemism of any floristic region; 90% of its 1367 native vascular plant taxa are classified as endemic. We used the IUCN's assessment of the complete single-island endemic (SIE) vascular plant flora of Kauai, Hawaii, to assess the proportion and drivers of decline of threatened plants in an oceanic island setting. We compared the IUCN assessments with federal, state, and other local assessments of Kauai species or taxa of conservation concern. Finally, we conducted a preliminary assessment for all 1044 native vascular plants of Hawaii based on IUCN criterion B by estimating area of occupancy, extent of occurrence, and number of locations to determine whether the pattern found for the SIE vascular flora of Kauai is comparable to the native vascular flora of the Hawaiian Islands. We compared our results with patterns observed for assessments of other floras. According to IUCN, 256 SIE vascular plant taxa are threatened with extinction and 5% are already extinct. This is the highest extinction risk reported for any flora to date. The preliminary assessment of the native vascular flora of Hawaii showed that 72% (753 taxa) is threatened. The flora of Hawaii may be one of the world's most threatened; thus, increased and novel conservation measures in the state and on other remote oceanic islands are urgently needed. 相似文献
62.
Torres-Jardón R Keener TC 《Journal of the Air & Waste Management Association (1995)》2006,56(3):322-333
Ambient concentrations of ozone (O3), nitrogen oxides (NOx), total reactive nitrogen (NOy), nitric acid (HNO3), and hydrogen peroxide (H2O2) were measured during September 2003 at an urban site of Cincinnati, OH. The aim of this study was two-fold: to investigate whether O3 formation in this population exposure-type site is NOx, sensitive or volatile organic compound (VOC) sensitive and to test the practicality of using two combined observational-based methods to identify the sensitivity of O3 formation in midlevel polluted locations. The evaluation of the indicator species: NOy, O3/NOy, O3/HNO3, H2O2/ HNO3, and O3/(estimated NOx reaction products), as well as the combined hypothesis testing analysis of the weekend/weekday (WE/WD) differences of 1-hr and 8-hr average maximum O3 and of the 6:00 a.m.-9:00 a.m. average nitric oxide and NOx concentrations, show evidence that Cincinnati is likely VOC sensitive. Average WE 1-hr and 8-hr maximum O3, as well as duration of WE O3 accumulation, were not lower than the corresponding WD levels in spite of the observed significant reduction in NO, emissions on WE, a typical situation in VOC-sensitive locations. The possibility that the seasonal transition from summer to autumn could have influenced the results was also investigated through an exploratory analysis of the afternoon O3 maximum/NOx measured and of the WE/WD differences of peak O3 and morning average NO and NO, concentrations observed at this site from June through September 2003. The results suggest that a VOC-sensitive chemistry regime dominated along the summer season. The findings of this study suggest that additional reductions in regional NO, emissions in Cincinnati, a potential nonattainment area under the 8-hr O3 standard, may cause an increase in local O3. Future strategies to reduce O3 in Southwest Ohio should be further evaluated carefully. The combination of observational-based methods might provide a consistent complementary approach in the identification of the NO,-VOC sensitive characteristics of mid-to-moderate polluted urban areas. 相似文献
63.
Unapumnuk K Keener TC Lu M Khang SJ 《Journal of the Air & Waste Management Association (1995)》2006,56(5):618-627
Pyrolytic product distribution rates and pyrolysis behavior of tire-derived fuels (TDF) were investigated using thermogravimetric analyzer (TGA) techniques. A TGA was designed and built to investigate the behavior and products of pyrolysis of typical TDF specimens. The fundamental knowledge of TGA analysis and principal fuel analysis are applied in this study. Thermogravimetry of the degradation temperature of the TDF confirms the overall decomposition rate of the volatile products during the depolymerization reaction. The principal fuel analysis (proximate and ultimate analysis) of the pyrolytic char products show the correlation of volatilization into the gas and liquid phases and the existence of fixed carbon and other compounds that remain as a solid char. The kinetic parameters were calculated using least square with minimizing sum of error square technique. The results show that the average kinetic parameters of TDF are the activation energy, E = 1322 +/- 244 kJ/mol, a pre-exponential constant of A = 2.06 +/- 3.47 x 10(10) min(-1), and a reaction order n = 1.62 +/- 0.31. The model-predicted rate equations agree with the experimental data. The overall TDF weight conversion represents the carbon weight conversion in the sample. 相似文献
64.
65.
Goal and Scope
Blast-furnace sludge is a waste originating from pig-iron production and contains contaminants such as lead, zinc, fluoride and cyanide assumably contaminating the groundwater by leaching.Methods
We investigated the chemical composition of 27 samples of landfilled blast-furnace sludge in pore waters which were obtained by the centrifugation of fresh material and elution with water according to DIN 38414 part 4 (S 4).Results
The pore waters as well as the eluates were neutral to alkaline (pH 7.3 to 10.7) and were dominated by alkali and alkaline-earth metals as well as sulphate and nitrate. The concentrations of all elements and compounds investigated were mostly clearly larger in the pore waters than in the eluates. The average concentrations of environmentally relevant constituents such as lead (0,18 mg?1), zinc (1,5 mg l?1), fluoride (10,6 mg l?1), and total cyanide (1.8 mg l?1) in the pore waters were distinctly larger than the inspection value of the German Federal soil Protection Ordinance for the pathway soil-groundwater. Lead, zinc, and total cyanide concentrations in the pore waters were largely underestimated by the eluates, as these concentrations were 70 to 90% lower in the eluates compared to the pore waters.Conclusion
In the case of landfilled blast-furnace sludge, eluates according to DIN 38414 part 4 (S 4) provide low concentrations which are unrealistic to forecast concentrations in the seepage water. 相似文献66.
Samuel R. Scholes Ana B. Sendova-Franks S. Tim Swift Chris Melhuish 《Behavioral ecology and sociobiology》2006,59(4):531-540
A fundamental issue of collective intelligence is whether the collective pattern or process is based on environmental information
that explicitly codes for it or arises through self-organization of the individuals. Sometimes, these alternatives occur together.
Adaptive systems may also be capable of utilizing different types of mechanism under different conditions. Sendova-Franks
et al. (Anim Behav 68:1095–1106, 2004) demonstrated evidence for a self-organization mechanism of brood sorting in the ant
Temnothorax albipennis, where the brood are sorted in a series of bands or concentric annuli that increase in size with distance from the colony
centre. The work by Cox and Blanchard (J Theor Biol 204:223-238, 2000) suggests an alternative or complementary mechanism
whereby the brood pattern is specified by the template of a CO2 gradient. Here, we test for a gaseous template as a necessary condition for brood sorting. Under the experimental condition,
we pumped the air out of the nest continuously to prevent the accumulation of any gaseous substances. We compared the brood
pattern between the experimental and control conditions according to four characteristics: mean distance from centre, mean
nearest-neighbour distance, shape and area. Under the experimental condition, the order of brood types according to the first
two characteristics was the same as in the control. The area of the brood pattern was smaller, and its shape elongated under
the experimental condition. As expected on the basis of these differences, mean distance from centre was greater and mean
nearest-neighbour distance was smaller under the experimental condition (although not statistically significantly) and by
the expected amount. We found evidence that ants avoid placing brood in the strongest airflow stream. This could explain the
reduced area and elongated shape of the brood pattern under the experimental condition. We conclude that a gaseous template
is not a necessary condition for brood sorting.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
67.
Experimental and natural changes in the peacock's (Pavo cristatus) train can affect mating success 总被引:4,自引:0,他引:4
Petrie et al. (1991) demonstrated a correlation between the degree of elaboration of peacocks' trains and their mating success, and also showed that this correlation occurred because females preferred to mate with the male that had the most elaborate train of those sampled on the lek. Although these data suggest that female choice is responsible for non-random mating in this species, they do not conclusively show that train morphology is the cue that females respond to, because they do not rule out the possible influence of another unidentified variable which is correlated with train elaboration. This paper presents an experimental test of the importance of the peacock's train in determining male mating success. If the number or arrangement of eye-spots in the peacock's train influences mating success, then changing the number of eye-spots should change mating success. This prediction was tested in an experiment where the trains of male peafowl (Pavo cristatus) were manipulated by removing a number of eye-spots between mating seasons. Peacocks with eye-spots removed showed a significant decline in mating success between seasons compared with a control group. This result, together with the observational data, supports the hypothesis that the peacock's train has evolved, at least in part, as a result of female choice. 相似文献
68.
This work examines the abilities of two smectite minerals (SWa-1 and Wyoming montmorillonite) to adsorb ferrous iron at concentrations from 0.037 mM (2 ppm) to 2.5 mM (240 ppm) over a range of pHs from 4.0 to 8.0. Both sorption isotherm and sorption edge data are presented. Ferrous sorption (Fe(aq)2+ = 0.1 mM) to both SWa-1 and Wyoming montmorillonite over the pH range 4.0-6.75 is relatively constant at approximately 1000 l kg(-1) for both minerals. Sorption in this pH range is attributed to the cation exchange capacity of the clay along the basal surfaces. At pH values above 6.75 the amount of ferrous iron sorbed increases dramatically. At pH 8, sorption (Fe(aq)+ = 0.1 mM) reaches 6600 l kg(-1) and 8000 l kg(-1) for Swa-1 and Wyoming montmorillonite respectively. This is attributed to the specific interaction between ferrous ions and surface sites along mineral edges. The overriding geochemical implication is that in reduced sediments containing more than a few percent clay, the pool of sorbed ferrous iron is vast. This pool of reduced iron is both redox labile and bio-available and is not readily indicated by simple measurement of dissolved Fe2+. 相似文献
69.
McFarland MJ Nelson TM Palmer GR 《Journal of the Air & Waste Management Association (1995)》2004,54(5):614-622
To effectively reduce the environmental compliance costs associated with meeting hazardous air pollutant emission requirements, the U.S. Environmental Protection Agency's Data Quality Objective (DQO) process has been proposed as a suitable framework for establishing a defensible monitoring program. Through the use of a hazardous materials pilot study, the variability in the composite vapor pressure for regulated handwipe cleaning solvents was established. These results served as inputs to the DQO process, which identified that for facility decision-makers to claim with a 99% confidence level that the facility is in compliance with the National Emission Standards for Hazardous Air Pollutants (NESHAP), a minimum of 12 handwipe cleaning solvent compliance samples (taken at random every 6 months) must have a composite vapor pressure equal to or below the regulatory limit of 45 mmHg at 20 degrees C. Implementation of the DQO-based compliance-sampling plan eliminates the need for an affected facility to sample all regulated handwipe cleaning solvents while still maintaining a reasonably high level of confidence in the compliance status of its regulated sources. The approach described for designing a defensible compliance sampling plan can be extended to other aspects of the aerospace NESHAP rule, including compliance sampling for surface coating, chemical depainting, and hazardous waste disposal. 相似文献
70.
The estimation of PAH bioavailability in contaminated sediments using hydroxypropyl-beta-cyclodextrin and Triton X-100 extraction techniques 总被引:1,自引:0,他引:1
A study was conducted to investigate whether cyclodextrins and surfactants can be used to predict polycyclic aromatic hydrocarbon (PAH) bioavailability in contaminated sediments. Two sediment samples were extracted with aqueous solutions of hydroxypropyl-beta-cyclodextrin (HPCD) and Triton X-100. PAH removal during extraction was compared with PAH removal during biodegradation and solid-phase extraction. The latter two methods were used as reference methods to establish which part of the PAHs could be biodegraded and to what extent biodegradation was governed by bioavailability limitations. It was demonstrated that HPCD extraction followed solid-phase extraction and removed primarily readily bioavailable PAHs, while Triton X-100 extracted both readily and poorly bioavailable PAHs. Moreover, HPCD did not affect the degradation of PAHs in biodegradation experiments, while Triton X-100 enhanced the degradation of low molecular weight PAHs. It was concluded that HPCD extraction may provide a good method for the prediction of PAH bioavailability. Triton X-100 extraction is unfit for the prediction of PAH bioavailability. 相似文献