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51.
52.
Whilst mitigation has dominated policy and research agendas in recent years there is an increasing recognition that communities also need to be preparing for change that is unavoidable, partially a consequence of anthropogenic greenhouse gases already emitted to the atmosphere. The perceived need for adaptation has also received additional impetus through the high public profile now given to the impacts of current day weather variability, particularly the significant economic and social costs associated with recent extreme events. However, being a relatively new focus for both research and policy communities; practical evidence of the extent, feasibility, efficiency, and cost effectiveness of potential adaptation options remains largely lacking. In response, this paper seeks to make a contribution to this embryonic but evolving knowledge base by considering the theoretical underpinnings of adaptation and ultimately how this translates into practice ‘in the real world’. The analytical commentary, based on a bottom-up approach involving iterative engagement with key stakeholders and experts, reflects on the identification of measures that are either innovative or examples of good practice in reducing or transferring climate risks, as well as considering those ‘enabling’ institutional structures and processes that act to support implementation on the ground. The paper concludes by synthesising the key findings to date in order to highlight some of the opportunities for, and barriers to, adaptation activity.  相似文献   
53.
We examined multiple mate choice criteria in Cophixalus ornatus, a terrestrial breeding, microhylid frog. Mate choice consisted of three stages: mate attraction (male calling), courtship (male behavior between the call site and the nest), and nest site selection by the female. For male C. ornatus, the possession of a call with low dominant frequency relative to calling neighbors increased the probability that they would attract females. Dominant frequency was negatively correlated with age independent of male mass and snout vent length. When escorting the female from the call site to their nest, males traveled along more convoluted paths than when returning to the nest alone. The convolution of the path was, therefore, considered an aspect of courtship. Females released eggs into nests with structural characteristics typical of nests constructed by older males. Thus, females increased their chances of locating an acceptable nest by preferentially approaching males with lower dominant frequencies. This study is the first to demonstrate that age, independent of mass or snout-vent length, can influence call characteristics in anurans, and it is also the first to demonstrate the importance of male age to female mate choice in an amphibian.  相似文献   
54.
The in vivo methylating capability of the organophosphorus insecticide tetrachlorvinphos, assayed by the formation of 7-methyl-guanine in mouse liver, was investigated. Following intraperitoneal injection of male mice with different doses of the 14C-insecticide, labelled at the OCH3 groups, the total and specific radioactivity of nucleic acids and protein were determined. The 14C-labelling in the isolated macromolecules reached its maximum 24 hours following administration of the insecticide. Analysis of the acid hydrolysate of DNA and of RNA on Dowex-50 WX-12 revealed the presence of (7-14C) methylguanine. At maximum 14C-labelling, the amount of radioactive 7-MeGu, calculated as fraction of total dose, was around 9 X 10(-5) and 39 X 10(-5) for DNA and RNA, respectively.  相似文献   
55.
3H-Trifluralin was synthesized by condensation of 3H-4-chloro-3,5-dinitro-alpha, alpha, alpha-trifluorotoluene with di-n-propylamine. After incubation of trifluralin with Aspergillus carneus, Fusarium oxysporum and Trichoderma viride for 10 days, a small percentage (less than 10%) of unchanged herbicide was recovered in the extractable fraction. This indicates a fairly rapid degradation of the herbicide by the fungal species. Other than trifluralin, the culture medium contained at least five labelled products: 2,6-dinitro-N-n-propyl-alpha, alpha, alpha-trifluoro-p-toluidine; 2,6-dinitro-alpha, alpha, alpha-trifluoro-p-toluidine; 2-amino-6-nitro-alpha, alpha, alpha-trifluoro-p-toluidine, 2,6-dinitro-4-trifluoromethyl phenol and a major polar product which constituted more than 50% of the total extractable transformation products. A pathway, which simulates that of aerobic degradation of the herbicide in soil, is suggested for the microbiological degradation of trifluralin.  相似文献   
56.
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   
57.

Goal and Scope

Since 1984 the Environmental Protection Agency (LfU) of the State of Baden-Wuerttemberg has been investigating the heavy metal burden of earthworms from representative long-term forest observation plots. These investigations are aimed at elucidating and assessing adverse effects of pollutants on the soil biocenosis.

Methods

At first only lead and cadmium were measured in the worms; in repetitive measurements over the years further metals or metalloid elements such as aluminum, arsenic, chromium, cobalt, copper, manganese, mercury, nickel, thallium, vanadium, and zinc were added to the agenda.

Results and Conclusion

The frequency distribution of the metals in the earthworms was characterized statistically. For the first time state-wide background values, normal values and threshold values were established for all the elements measured. A comparable study with a similar range of parameters is known neither nationally nor internationally. Time trend studies have been available for lead and cadmium since 1985/86, and for zinc since 1987. The studies show a steady decrease of the heavy metals on a state-wide average and especially in the ‘Odenwald’ and ‘Black Forest’ hills with their formerly highly polluted earthworm habitats. Today, the level of these metals in the earthworms is low with few exceptions. This holds true for other heavy metals as well.

Recommendations and Perspectives

The state-wide decreasing very low heavy metal burden of forest observation plots far from known emission sources can be considered a success of air pollution abatement measures. Because of the ongoing atmospheric deposition of heavy metals, regular observation should continue in order to estimate time trends and to recommend the reduction of emissions when precautionary values (part 2) are exceeded.  相似文献   
58.
The concentrations of heavy metals (Cd, Cu, Ni, Pb, Zn and Mn) and macroelements (K, Na, Ca and Mg) were determined in green alga Enteromorpha sp. from the coastal zone of the southern Baltic including Gulf of Gdańsk and Vistula Lagoon in 2000-2003. In order to estimate the degree of accumulation of each element by the green alga, concentration and discrimination factors (CFs) with respect to seawater were calculated. The results of factor analysis (FA) and ANOVA clearly indicate geographical differences between concentrations of chemical elements. Enteromorpha sp. from Vistula Lagoon and the southern Baltic exhibited higher levels of Mn and Ni, and Na and K, respectively. Anthropogenic impact of Cu, Pb and Zn, possibly originated from municipal sewage, was identified in alga samples collected in the Gulf of Gdańsk, especially in the vicinity of Gdynia. From comparison our data with those published earlier results that Pb content in Enteromorpha sp. from the Gulf of Gdańsk decreased within 1978-2003 reflecting reducing use of leaded petrol in Baltic countries in this period. The alga Enteromorpha sp. can be used for biomonitoring surveys of metal contaminants in coastal areas of the Baltic Sea.  相似文献   
59.
Noise measurements and questionnaire inquiries were carried out for 124 workers of a rolling stock plant to develop a hearing conservation program. On the basis of that data, the risk of noise-induced hearing loss (NIHL) was evaluated. Additionally, the workers' hearing ability was assessed with the (modified) Amsterdam inventory for auditory disability and handicap, (m)AIADH. The workers had been exposed to noise at A-weighted daily noise exposure levels of 74-110 dB for 1-40 years. Almost one third of the workers complained of hearing impairment and the (m)AIADH results showed some hearing difficulties in over half of them. The estimated risk of hearing loss over 25 dB in the frequency range of 3-6 kHz was 41-50% when the standard method of predicting NIHL specified in Standard No. ISO 1999:1990 was used. This risk increased to 50-67% when noise impulsiveness, coexposure to organic solvents, elevated blood pressure and smoking were included in calculations.  相似文献   
60.
Adam Erickson 《Ambio》2015,44(5):343-352
New institutions are critically needed to improve the resilience of social–ecological systems globally. Watershed management offers an important model due to its ability to govern mixed-ownership landscapes through common property regimes, translating national goals into local action. Here, I assess the efficacy of state watershed management institutions in the Pacific Northwest, based on their ability to support local watershed groups. I use document analysis to describe and compare state institutions in Washington, Oregon, Idaho, and California. Results indicate that state institutional efficiency and resilience are the key factors determining watershed group activity and stability. The primary drivers of institutional efficiency and resilience were institutional unification, robust funding portfolios, low agency conflict, and strong support for economic multiplier effects, creative partnerships, and scholarly research. My findings elucidate the critical role of institutional efficiency and resilience in governing dynamic and complex social–ecological systems, enabling the flexibility to address emergent transformations.  相似文献   
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