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671.
Strategies to reduce, halt, and reverse global declines in marine biodiversity are needed urgently. We reviewed, coded, and synthesized historical and contemporary marine conservation strategies of the Kitasoo/Xai'xais First Nation in British Columbia, Canada to show how their approaches work. We assessed whether the conservation actions classification system by the Conservation Measures Partnership was able to encompass this nation's conservation approaches. All first-order conservation actions aligned with the Kitasoo/Xai'xais First Nation's historical and contemporary marine conservation actions; hereditary chief management responsibility played a key role. A conservation ethic permeates Kitasoo/Xai'xais culture, and indigenous resource management and conservation existed historically and remains strong despite extreme efforts by colonizers to suppress all indigenous practices. The Kitasoo/Xai'xais's embodiment of conservation actions as part of their worldview, rather than as requiring actions separate from everyday life (the norm in nonindigenous cultures), was missing from the conservation action classification system. The Kitasoo/Xai'xais are one of many indigenous peoples working to revitalize their governance and management authorities. With the Canadian government's declared willingness to work toward reconciliation, there is an opportunity to enable First Nations to lead on marine and other conservation efforts. Global conservation efforts would also benefit from enhanced support for indigenous conservation approaches, including expanding the conservation actions classification to encompass a new category of conservation or sacredness ethic. 相似文献
672.
673.
Jordan Wood Jonathan D. Ballou Taylor Callicrate Jeremie B. Fant M. Patrick Griffith Andrea T. Kramer Robert C. Lacy Abby Meyer Sara Sullivan Kathy Traylor-Holzer Seana K. Walsh Kayri Havens 《Conservation biology》2020,34(6):1416-1425
Maintaining a living plant collection is the most common method of ex situ conservation for plant species that cannot be seed banked (i.e., exceptional species). Viability of living collections, and their value for future conservation efforts, can be limited without coordinated efforts to track and manage individuals across institutions. Using a pedigree-focused approach, the zoological community has established an inter-institutional infrastructure to support long-term viability of captive animal populations. We assessed the ability of this coordinated metacollection infrastructure to support the conservation of 4 plant species curated in living collections at multiple botanic gardens around the world. Limitations in current practices include the inability to compile, share, and analyze plant collections data at the individual level, as well as difficulty in tracking original provenance of ex situ material. The coordinated metacollection framework used by zoos can be adopted by the botanical community to improve conservation outcomes by minimizing the loss of genetic diversity in collections. We suggest actions to improve ex situ conservation of exceptional plant species, including developing a central database to aggregate data and track unique individuals of priority threatened species among institutions and adapting a pedigree-based population management tool that incorporates life-history aspects unique to plants. If approached collaboratively across regional, national, and global scales, these actions could transform ex situ conservation of threatened plant species. 相似文献
674.
Cuyler Christine Rowell Janice Adamczewski Jan Anderson Morgan Blake John Bretten Tord Brodeur Vincent Campbell Mitch Checkley Sylvia L. Cluff H. Dean Côté Steeve D. Davison Tracy Dumond Mathieu Ford Barrie Gruzdev Alexander Gunn Anne Jones Patrick Kutz Susan Leclerc Lisa-Marie Mallory Conor Mavrot Fabien Mosbacher Jesper Bruun Okhlopkov Innokentiy Mikhailovich Reynolds Patricia Schmidt Niels Martin Sipko Taras Suitor Mike Tomaselli Matilde Ytrehus Bjørnar 《Ambio》2020,49(3):805-819
Ambio - Muskoxen (Ovibos moschatus) are an integral component of Arctic biodiversity. Given low genetic diversity, their ability to respond to future and rapid Arctic change is unknown, although... 相似文献
675.
Steroid estrogens such as estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) have been suspected to be the main contaminants, which can affect the endocrine system of animals. Many authors have investigated these chemicals in the domestic wastewater treatment plants (WTP). However, wastewater from industries producing steroid contraceptives has not got ample attention. From the environmental point of view, the four steroids are very significant because even very low concentrations (ng/L) can cause reproductive disturbances in human, livestock and wildlife. The main purpose of the present investigation was to develop an analytical method for the determination of the four steroid estrogens present in WTP of a pharmacy factory, mainly producing contraceptive medicine in Beijing, China. Analysis was performed by solid-phase extraction (SPE) system and liquid chromatography combined with tandem mass spectrometry (LC/MS/MS). The average recoveries from effluent samples ranged from 88% to 103% and the precision of the method ranged from 9% to 4%. Based on 0.5-L wastewater samples, the limit of quantification (LOQ) was determined at 0.7 ng/L for E1, 0.8 for E2, 0.9 ng/L for E3, and 0.5 ng/L for EE2 in influent, and 1.0 ng/L for E2 and EE2, and 2.0 ng/L for E1 and E3 in effluent. In the influent samples, average concentrations of 80, 85, 73 and 155 ng/L were determined for E1, E2, E3 and EE2, respectively, showing that they were removed in this WTP to the extent of 79, 73, 85 and 67%, respectively. 相似文献
676.
Zhang Y Ruan L Fasola M Boncompagni E Dong Y Dai N Gandini C Orvini E Ruiz X 《Environmental monitoring and assessment》2006,118(1-3):355-368
The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed.
We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River
Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial
waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan,
e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by
foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in
the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold
that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e.
Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were
lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results
do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace
metal concentration differed significantly among the three study areas, these differences were minor and were not consistent
among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with
our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the
other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators
of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in
the food chain are better indicators for the other elements. 相似文献
677.
Martín-Díaz ML Tuberty SR McKenney CL Blasco J Sarasquete C Delvalls TA 《Environmental monitoring and assessment》2006,116(1-3):169-184
Individuals of the crayfish Procambarus clarkii (males and females) were exposed simultaneously to cadmium and zinc during 21 days. Exposure concentrations were those determined
at the Guadiamar river after the Aznalcóllar mining spill (SW, Spain): 10 and 30 μg L−1 of cadmium and 1000 and 3000 μg L−1 of zinc. Three biomarkers (MT: metallothioneins like proteins, VTG: vitellogenin/vitellin like proteins and histopathology)
together with heavy metal bioaccumulation were determined in soft tissues of male and female P. clarkii. At the concentrations tested, increasing cadmium exposure resulted in increasing cadmium bioaccumulation and increasing subletal
effects (induction of MT, VTG and histopathological damage in tissues). Nevertheless, although increasing zinc exposure showed
increasing VTG induction and histopathological damages, not a positive relationship was determined with MT induction. Concerning
to responses determined in male and female crayfishes only differences were found between sexes at the highest cadmium exposure
concentration related to bioaccumulation in hepatopancreas tissues. Biomarkers responses to heavy metal contamination in this
crayfish, even VTG induction not before tested in heavy metal contamination assessment in crustaceans resulted potential tools
for the monitoring of heavy metal environmental contamination. 相似文献
678.
Jim CY 《Environmental monitoring and assessment》2006,116(1-3):53-80
Urban trees serve important environmental, social and economic functions, but similar to other natural endowments they are
not customarily depicted in monetary terms. The needs to augment protection, funding and community support for urban greening
call for proper valuation. Heritage trees (HTs), the cream of urban-tree stock, deserve special attention. Existing assessment
methods do not give justice to outstanding trees in compact cities deficient in high-caliber greenery, and to their social-cultural-historical
importance. They artificially separate evaluation from valuation, which should be a natural progression from the former. Review
of tree valuation methods suggested the formula approach to be more suitable than contingent valuation and hedonic pricing,
and provided hints on their strengths and weaknesses. This study develops an alternative formulaic expert method (FEM) that
integrates evaluation and valuation, maximizes objectivity, broadly encompasses the key tree, tree-environment and tree-human
traits, and accords realistic monetary value to HTs. Six primary criteria (dimension, species, tree, condition, location,
and outstanding consideration) branched into 45 secondary criteria, each allocated numerical marks. Each primary criterion
was standardized to carry equal weight, and a tree's maximum aggregate score is capped at 100. A Monetary Assignment Factor
(MAF) to consign dollar value to each score unit was derived from three-year average per m2 sale price of medium-sized residential flats. The applicability of FEM was tested on selected HTs in compact Hong Kong. The
aggregate score of a tree multiplied by MAF yielded monetary value, which was on average 66 times higher than the result from
the commonly-adopted Council of Tree and Landscape Appraisers method. The computed tree values could be publicized together
with multiple tree benefits to raise understanding and awareness and rally support to protect HTs. The property-linked FEM
could be flexibly applied to other cities, especially to assess HTs in compact developing cities. 相似文献
679.
Abstact The present study was designed to evaluate indirect, non-invasive, on-line measurement of biofilm thickness using an electrical capacitance technique. Several assays were carried out and the results showed that, at a frequency of 1 kHz, electrical capacitance could be used to measure biofilm thickness indirectly (with a correlation coefficient of 0.9495). The reproducibility revealed by the assays was also highly satisfactory.However, in contrast to what was expected, there was an inverse relationship between electrical capacitance and biofilm thickness, i.e. electrical capacitance diminished with the increase in the biofilm thickness.The tests were also carried out at different frequencies (1 kHz, 10 kHz and 100 kHz) 相似文献
680.
Vaughan G Quinn PT Green AC Bean J Roscoe HK van Roozendael M Goutail F 《Journal of environmental monitoring : JEM》2006,8(3):353-361
We present in this paper fifteen years' measurements, from March 1991 to September 2005, of stratospheric NO2 vertical columns measured by a SAOZ zenith-sky visible spectrometer. The instrument spent most of its time at Aberystwyth, Wales, with occasional excursions to other locations. The data have been analysed with the WinDOAS analysis program with low-temperature high-resolution NO2 cross-sections and fitting a slit function to each spectrum. Because of a change in detector in May 1998 there is some uncertainty about the relative changes before and after this date, which are partially constrained by the results of an intercomparison exercise. However, the effect of the Mt Pinatubo aerosol cloud is very evident in the data from 1991-94, with a decrease of 10% in NO2 in the summer of 1992 (the SAOZ was located in Lerwick, Scotland during the winter of 1991-92 and observed very low NO2 values but these cannot be directly compared to the Aberystwyth data). To focus more on interannual and long-term variations in NO2, a seasonal variation comprising an annual and semi-annual component was fitted to the morning and evening twilight separately from 1995 to the present. This fit yielded average NO2 columns of 4.08 x 10(15) cm(-2) and 2.68 x 10(15) cm(-2) for the evening and morning twilight, respectively, with a corresponding annual amplitude of +/-2.08 x 10(15) cm(-2) and +/-1.50 x 10(15) cm(-2). Departures from the fitted curve show a trend of 6% per decade, consistent with that reported elsewhere, for the period 1998-2003, but in the past two years a distinct interannual variation of amplitude of approximately 8% has emerged. 相似文献