Headwinds: sustainability as a theme in contemporary public art

Sustainability as an increasingly popular theme in Contemporary Public Art. The three pillar model of sustainability is used to examine works that deal specifically with the topic of economic, social and environmental sustainability. Viewing these contemporary art works through the lens of sustainability gives new meaning and significance to what many of these contemporary artist are trying to achieve.     

Tissue heavy metal concentrations of stranded California sea lions (Zalophus californianus) in Southern California

Concentrations of nine heavy metals (As, Cd, Cu, Fe, Hg, Pb, Mn, Mo and Zn) were determined in the hepatic and renal tissues of 80 stranded California sea lions (Zalophus californianus). Significant age-dependant increases were observed in liver and kidney concentrations of cadmium and mercury, and renal zinc concentrations. Hepatic iron concentrations were significantly higher in females than males. Animals with suspected domoic acid associated pathological findings had significantly higher concentrations of liver and kidney cadmium; and significantly higher liver mercury concentrations when compared to animals classified with infectious disease or traumatic mortality. Significantly higher hepatic burdens of molybdenum and zinc were found in animals that died from infectious diseases. This is the largest study of tissue heavy metal concentrations in California sea lions to date. These data demonstrate how passive monitoring of stranded animals can provide insight into environmental impacts on marine mammals.     

Atmospheric Deposition and Ozone Levels in Swiss Forests: Are Critical Values Exceeded?

Air pollution affects forest health through atmospheric deposition of acidic and nitrogen compounds and elevated levels of tropospheric ozone (O₃). In 1985, a monitoring network was established across Europe and various research efforts have since been undertaken to define critical values. We measured atmospheric deposition of acidity and nitrogen as well as ambient levels of O₃ on 12, 13, and 14 plots, respectively, in the framework of the Swiss Long-Term Forest Ecosystem Research (LWF) in the period from 1995 to 2002. We estimated the critical loads of acidity and of nitrogen, using the steady state mass balance approach, and calculated the critical O₃ levels using the AOT40 approach. The deposition of acidity exceeded the critical loads on 2 plots and almost reached them on 4 plots. The median of the measured molar ratio of base nutrient cations to total dissolved aluminium (Bc/Al) in the soil solution was higher than the critical value of 1 for all depths, and also at the plots with an exceedance of the critical load of acidity. For nitrogen, critical loads were exceeded on 8 plots and deposition likely represents a long-term ecological risk on 3 to 10 plots. For O₃, exceedance of critical levels was recorded on 12 plots, and led to the development of typical O₃-induced visible injury on trees and shrubs, but not for all plots due to (1) the site specific composition of O₃ sensitive and tolerant plant species, and (2) the influence of microclimatic site conditions on the stomatal behaviour, i.e., O₃ uptake.     

Flow visualisation studies of aerodynamic characteristics of an open-top chamber

Studies to determine potential locations of ingress of ambient air into an open-top chamber, using flow visualisation, are described. Rates of chamber ventilation necessary to avoid ambient air entrainment have been estimated from wind tunnel experiments. The dependence of the exit velocity of air from the chamber on the ambient air velocity was non-linear, so that for low wind speeds other mechanisms are more important than for high ambient air flows. Wind speeds ranged from 0.5m s(-1)相似文献   

Antibiotika als Umweltkontaminanten — Effekte auf Bodenbakterien

Goal and scope

Among the human and veterinary pharmaceuticals, antibiotics form an important group. Recent research addressed the environmental ‘side effects’ of antibiotics. Evidence for environmental effects of antibiotics has for example been found for the respiratory activity of soil microorganisms. In the present contribution, results of studies on the ecotoxicology of antibiotics that are based on the utilization of carbon substrates in so-called Biolog plates are summarized.

Methods, Results and Conclusions

The method of pollution-induced community tolerance (PICT) takes centre stage. PICT is based on the changes in community composition of environmental communities brought about by a toxicant, which lead to an overall increase in community tolerance to this toxicant. The suitability of such an increase in community tolerance as ecotoxicological endpoint had been the subject of several experiments. It was shown that effect testing of antibiotics requires supplementation of the communities with nutrients, and that the PICT method reveals antibiotic effects with a high specificity. In an application of PICT, effects of three classes of antibacterial compounds were investigated. Dose-response relationships were obtained for all substances, and effect concentrations were partly in the range of expected environmental concentrations. The possible risks of antibiotic use for an increase in the occurrence of antibiotic resistance genes in the environment are also touched upon, including the extent of natural resistance.

Outlook

Due to its specificity, the PICT method has shown to be a suitable ecotoxicological assay. Due to possible effects of tetracyclines on the structure of the soil microbial community, it is advised to use veterinary antibiotics with caution. The risks of an increase in the occurrence of antibiotic resistance in the environment should be investigated in more detail.     

Analysis of the biomechanical response of kidneys under blunt impact

OBJECTIVE: This study addresses the biomechanical response of isolated kidneys to traumatic insult. METHODS: Kidneys were subjected to blunt impact by using a freely swinging right cylindrical pendulum. Force-deformation characteristics were derived for 65 impacted adult pig kidneys. Renal injuries were classified by autopsy, and an injury risk analysis was performed. In addition a finite element model that simulated the experiments was implemented. RESULTS/CONCLUSIONS: The kidneys showed a viscoelastic response. An energy-based injury threshold was identified, with a strain energy density of 21 kJ/m(3) corresponding to a 50-percent risk of renal injury level AIS3 or higher. Finally, the impact tests were simulated using a finite element model of the kidney to investigate relevant injury mechanisms. The model predicted the renal capsule and underlying parenchyma to first fail at an impact energy level of 4.0 J, consistent with experimental results.     

Influence of corallivory, competition, and habitat structure on coral community shifts

The species composition of coral communities has shifted in many areas worldwide through the relative loss of important ecosystem engineers such as highly branched corals, which are integral in maintaining reef biodiversity. We assessed the degree to which the performance of recently recruited branching corals was influenced by corallivory, competition, sedimentation, and the interactions between these factors. We also explored whether the species-specific influence of these biotic and abiotic constraints helps to explain recent shifts in the coral community in lagoons of Moorea, French Polynesia. Population surveys revealed evidence of a community shift away from a historically acroporid-dominated community to a pocilloporid- and poritid-dominated community, but also showed that the distribution and abundance of coral taxa varied predictably with location in the lagoon. At the microhabitat scale, branching corals grew mainly on dead or partially dead massive Porites ("bommies"), promontories with enhanced current velocities and reduced sedimentation. A demographic study revealed that growth and survival of juvenile Pocillopora verrucosa and Acropora retusa, the two most common branching species of each taxon, were affected by predation and competition with vermetid gastropods. By 24 months of age, 20-60% of juvenile corals suffered partial predation by corallivorous fishes, and injured corals experienced reduced growth and survival. A field experiment confirmed that partial predation by corallivorous fishes is an important, but habitat-modulated, constraint for branching corals. Competition with vermetid gastropods reduced growth of both branching species but unexpectedly also provided an associational defense against corallivory. Overall, the impact of abiotic constraints was habitat-specific and similar for Acropora and Pocillopora, but biotic interactions, especially corallivory, had a greater negative effect on Acropora than Pocillopora, which may explain the local shift in coral community composition.     

Improving the prevention of environmental risks with convertible bonds

This paper considers a limited liability firm that needs external funds in order to invest in an activity that presents an environmental risk for the Society. When the firm's risk-reducing activities cannot be observed by the lenders, we show that the issue of convertible bonds can create incentives to improve prevention. Convertible bonds allow the holder to exchange his bonds for a fixed number of the firm's shares. The use of such hybrid securities could either complement or be an alternative to the American CERCLA legislation about lender extended liability. We define an optimal convertible bond contract that induces unchanged economic profits for the bank, more prevention and higher expected net revenues for the firm and a higher expected social welfare than with standard debt. Our results hold true both with and without extended liability.     

A macroinvertebrate assessment of Ozark streams located in lead–zinc mining areas of the Viburnum Trend in southeastern Missouri, USA

The Viburnum Trend lead–zinc mining subdistrict is located in the southeast Missouri portion of the Ozark Plateau. In 2003 and 2004, we assessed the ecological effects of mining in several watersheds in the region. We included macroinvertebrate surveys, habitat assessments, and analysis of metals in sediment, pore water, and aquatic biota. Macroinvertebrates were sampled at 21 sites to determine aquatic life impairment status (full, partial, or nonsupport) and relative biotic condition scores. Macroinvertebrate biotic condition scores were significantly correlated with cadmium, nickel, lead, zinc, and specific conductance in 2003 (r?=??0.61 to ?0.68) and with cadmium, lead, and pore water toxic units in 2004 (r?=??0.55 to ?0.57). Reference sites were fully supporting of aquatic life and had the lowest metals concentrations and among the highest biotic condition scores in both years. Sites directly downstream from mining and related activities were partially supporting, with biotic condition scores 10% to 58% lower than reference sites. Sites located greater distances downstream from mining activities had intermediate scores and concentrations of metals. Results indicate that elevated concentrations of metals originating from mining activities were the underlying cause of aquatic life impairment in several of the streams studied. There was general concurrence among the adversely affected sites in how the various indicators responded to mining activities during the overall study.