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11.
The risks related to global climate change are seen as threats to companies, taking into consideration their impact on the return on investment. In order to mitigate climate risk and introduce new opportunities to financiers, companies need to identify, manage, and report climate risks. The purpose of this paper is to investigate the climate risks disclosed by the 100 largest companies in the world, according to the Bloomberg and Price Waterhouse Coopers (PwC 2015) classification, and identify some characteristics of these companies that explain the disclosure level of such information. Preliminary results revealed that of the companies investigated, 14% did not disclose any climate risk information in the Carbon Disclosure Program (CDP) report. Also, from the companies that disclosed information according to the Global Reporting Initiative (GRI), 9.9% did not provide information regarding policies, actions, and strategies for mitigating the risks related to climate change. The results shown by the content analysis suggested that, in general, there is still a low level of disclosure about climate risks by these companies. The final results through econometric instruments and statistical tests indicate that the size of the company or the fact that corporations are from developed countries do not necessarily explain the level of information disclosed. However, the activity sector, the continent, and the efficiency of the Board of Directors are factors that strongly explain the level of climate risk disclosure. We conclude that more effort is needed to encourage an engaging attitude from corporations to develop actions, policies, and strategies to mitigate climate change risks and threats. In addition, the world’s largest companies should make a greater investment in climate risk disclosure.  相似文献   
12.
Thallium is a scarce, highly toxic element. There are several investigations that report Tl accumulation in plants of the family Brassicaceae. These plants could pose a risk in areas where Tl is present at higher concentrations than normal soils. The present study reports analyses of two wild Brassicaceae, Hirschfeldia incana and Diplotaxis catholica, growing spontaneously at five sampling sites moderately polluted with Tl and other trace elements in the Green Corridor of the Guadiamar river, Seville, S. Spain. In general, trace element content was unremarkable in all part plants, despite the concentrations present in soil. Thallium was the only element whose concentration in both plant species was above normal for plants (maximum values of 5.00 mgkg(-1) in H. incana flowers). There were significant positive correlations between total Tl in soil and Tl in both plant species. Transfer Coefficients (TC) for all elements were, in general, <1 for both species, except for Tl in flowers and fruits at some sites. The highest Enrichment Factor (EF) was found for Tl in H. incana fruits (EF = 607) and D. catholica flowers (EF = 321). H. incana was studied in a previous growing season (2004) in the same area, although the rainfall was 3 times more than in the year of the present study (2005), giving a maximum Tl content of 46.5 mgkg(-1) in H. incana flowers. The data presented here show that Tl content of plants growing in semi-arid conditions can be significantly influenced by precipitation. In dry years, plant Tl accumulation may be significantly reduced.  相似文献   
13.
A solid phase extraction procedure (SPE) is described for the quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulate matter (PM), as ubiquitous environmental pollutants routinely measured in air quality monitoring. A SPE cartridge was used based on a molecular imprinted polymer (MIP-SPE) properly tailored for selective retention of PAHs with 4 and more benzene fused rings. The performance of the clean-up procedure was evaluated with the specific concern of selective purification towards saturated hydrocarbons, which are the PM components mostly interfering GC analysis of target PAHs. Under optimized operative conditions, the MIP-SPE provided analyte recovery close to 95% for heavier PAHs, from benzo(α)pyrene to benzo(ghi)perylene, and close to 90% for four benzene rings PAHs, with good reproducibility (RSDs: 2.5%-5.9%). Otherwise, C17-C32 n-alkanes were nearly completely removed. The proposed method was critically compared with Solid Phase Micro Extraction (SPME) using a polyacrylate fiber. Both methods were successfully applied to the analysis of ambient PM2.5 samples collected at an urban polluted site. Between the two procedures, the MIP-SPE provided the highest recovery (R% ≥ 93%) for PAHs with 5 and more benzene rings, but lower for lighter PAHs. In contrast, SPME showed a mean acceptable R% value (∼ 80%) for all the investigated PAHs, except for the heaviest PAHs in the most polluted samples (R%: 110%-138%), suggesting an incomplete purification from the interfering n-hydrocarbons.  相似文献   
14.
The behavior and fate of triasulfuron (TRS) in water and soil systems were examined in laboratory studies. The degradation of TRS in both buffer solution and soil was highly pH-sensitive. The rate of degradation could be described with a pseudo first-order kinetic and was much faster at pH 4 than at pH 7 and 9. Aqueous hydrolysis occurred by cleavage of the sulfonylurea bridge to form 2-(2-chloroethoxy) benzenesulfonamide (CBSA) and [(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] (AMMT). AMMT was unstable in aqueous solutions in any pH condition but it degraded more quickly at pH 4 and 9. CBSA did not degrade in aqueous solutions or in enriched cultures but it underwent a quick degradation in the soil. The rates of TRS degradation in sterile and non-sterile soils were similar, suggesting that microorganisms played a minimal role in the breakdown process. This hypothesis is supported by the results of studies on the degradation of TRS by enriched cultures during which the molecule underwent a prevalently chemical degradation.  相似文献   
15.
The ecological burden of economic growth is a highly discussed issue. In this article, we focus on the set of European Union (EU) 15 countries in the period 1995–2014. We first decomposed emissions into six effects and afterward the decoupling-effort index was used to calculate the magnitude of impact that each factor has on it, considering the country group. For the group of the EU-15 in the pre-Kyoto period, CO2 changes are only negative in 1998 and 1999 considering the initial view (with respect to the base year of 1995), being positive for all the other years. This positive effect means increased emissions, for which many contributed the positive and significant effects of income per capita and the population effects. The most significant reductions in CO2 changes are verified in the years after the effective Kyoto commitment and observed mainly in the alternative view (year to year changes), for which many contributed the negative and significant effects of carbon intensity of petroleum products, energy intensity and conversion efficiency in the overall period. The effects elasticity decoupling and decoupling effort do not seem to be controlled by the internal drivers of CO2 emissions. Policy makers should bet in policy instruments pointed in the sense of strengthening energy efficiency, in reducing petroleum products consumption and therefore dependency and on the structure of added value generated by the economy.  相似文献   
16.
Few studies have attempted to study the environmental Kuznets curve (EKC) hypothesis at the individual sector level using more than one sector at once. This paper investigates the existence of the EKC hypothesis in the Iberian countries (Portugal and Spain) using thirteen economic activity sectors for each, analyzing each individual sector’s cointegration and causality relationships considering carbon dioxide (CO2) emissions, sector gross value added and energy consumption. The findings of this paper using the autoregressive distributed lag (ARDL) approach only validate cointegration in six Portuguese sectors and in five of the Spanish sectors. Results confirm both short- and long-run bi-directional and unidirectional causality between economic growth, energy consumption and CO2 emissions, using the error correction model (ECM) and Toda and Yamamoto’s causality approaches. Moreover, results for Portuguese and Spanish sectors indicate an inverted U-shaped relationship only for one sector each. In some sectors there was evidence of a U-shaped relationship and in others the EKC hypothesis could be verified but no statistical significance was obtained. The study has significant contributions for sector policy, including implications to curtail energy pollutants by implementing environmental friendly regulations to sustain economic development at the sector level in the Iberian market. It also allows inferences to be made about the existence of different behaviors in comparative terms for the same economic activity sectors of the individual countries.  相似文献   
17.
The impairment of root growth and photosynthetical functioning are the main impacts of trace elements on woody plant seedlings. In this work, we assessed the response of Holm oak (Quercusilex subsp. ballota) and mastic shrub (Pistacia lentiscus) seedlings to high concentrations of Cd and Tl in the rhizosphere. These are non-essential trace elements, with a potential high mobility in the soil-plant system. Seedlings of these species are frequently used in the afforestation of degraded soils in mining areas. Plants were exposed to different levels of Cd (20, 80 and 200 mg L−1) and Tl (2, 10 and 20 mg L−1) in a sand culture. Biomass allocation, growth rates, chlorophyll fluorescence and gas exchange were studied. Both metals affected root biomass. Cadmium produced an increase in the root mass ratio and a decrease in the specific leaf area of the plants in oak seedlings, while Tl did not provoke such response. Mastic plants were more sensitive to Tl and Cd than oak plants. Between elements, Tl provoked more severe toxic effects in the plants, affecting the antennae complexes and reaction centers of the photosystem II. Both elements decreased net assimilation rates (down to a 20% of the control plants) and stomatal conductance (5-10% of the values for the control plants). Cadmium was highly retained in the roots of both species, while Tl was highly translocated into the leaves. In general, Holm oak showed a higher tolerance for Cd than for Tl, and a higher resistance to both metals than mastic shrub, due to a high capacity for Cd retention at the root level. However, such accumulation in roots may induce water stress in the seedling exposed to Cd.  相似文献   
18.
Four dairy cattle farms considered representative of Northern Spain milk production were studied. Cattle waste was characterised and energy consumption in the farms was inventoried. Methane emissions due to slurry/manure management and fuel consumption on the farms were calculated. The possibility of applying anaerobic digestion to the slurry to minimise emissions and of using the biogas produced to replace fossil fuels on the farm was considered. Methane emissions due to slurry management (storage and use as fertiliser) ranged from 34 to 66 kg CH4 cow−1 year−1 for dairy cows and from 13 to 25 kg CH4 cow−1 year−1 for suckler calves. Cattle on these farms are housed for most of the year, and the contribution from emissions from manure dropped in pastures is insignificant due to the very low methane conversion factors. If anaerobic digestion were implemented on the farms, the potential GHG emissions savings per livestock unit would range from 978 to 1776 kg CO2 eq year−1, with the main savings due to avoided methane emissions during slurry management. The methane produced would be sufficient to supply digester heating needs (35-55% of the total methane produced) and on-farm fuel energy requirements.  相似文献   
19.
While many scientific assessments have been recommending general strategies for biodiversity conservation under climate change, translation of these recommendations into specific actions and practice has been limited. Focusing on two biomes, rainforest and wetlands in biodiverse South East Queensland, Australia, we demonstrate how general principles can be translated into specific actions for stakeholders and responsible agencies. We synthesize research that is contextualizing protection of refugia and habitat connectivity, establishing baseline data sets to detect change and developing strategic conservation planning scenarios to adjust reserve boundaries or situate new reserves. This has been achieved by coupling spatial information on biological assets (i.e. ecosystems and species) with future climate scenarios and process models to anticipate movement of critical habitats. Conservation planning software is also being used to prioritize investment to meet specific objectives. This approach is enabling us to identify at-risk biological assets, opportunities to ameliorate threats and obstacles to delivering regional adaptation actions. A larger total reserved area is needed, with proactive planning to capture areas further inland and along watercourses. Major obstacles include conflict between urbanization and priorities for habitat conservation and the need for greater levels of investment for monitoring programmes and to protect landward shifted wetlands on private land.  相似文献   
20.
Bite damage patterns have long been used to estimate shark species and body size, with somewhat limited success. The lack of fit between damage patterns and shark size is partially due to variation in tooth size and shape within an individual. The ability to accurately predict body size from bite patterns is important for better understanding the ecological and behavioral underpinnings of shark bites/attacks on marine organisms, humans, and submarine equipment. To this end, we measured interdental distance (IDD) between the most labial teeth in the first six tooth files on both the upper and lower jaws, as well as the circumference of the portion of each jaw that bears teeth, for prepared jaw sets from fourteen shark species and regressed these data against total length. IDD is allometric as well as an accurate predictor of total length in all species examined, except Carcharhinus acronotus. Tooth-bearing circumference is also allometric and predictive of total length in all species. Though considerable overlap exists in IDD and circumference ranges among species for the total length ranges examined, Carcharodon carcharias and Isurus sp. can be differentiated from Carcharhinus limbatus, Carcharhinus brevipinna, and C. acronotus based on these values alone. When combined with knowledge of species-specific feeding behavior, geographic distribution, and habitat preferences, these simple measures from bite damage patterns allow quick, accurate assessment of shark size and potential species.  相似文献   
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