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101.
102.
Concentrations of eight elements were measured in Chelonia mydas and Lepidochelys olivacea eggs collected along the Pacific coast of Panama. Manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), and mercury (Hg) concentrations were similar to previous reports of these species from around the world, while lead (Pb) was lower than previous reports. Cd posed the highest health risk to people who regularly eat the eggs, with average consumption rates leading to target hazard quotients (THQ) of up to 0.35 ± 0.15. Our conclusions indicate that current turtle egg consumption in isolated, coastal Pacific communities may pose a health concern for young children, and that youth and young adults should limit their consumption of turtle eggs to reduce their total intake of nonessential metals.  相似文献   
103.
When applied to agricultural soils, phosphate fertilizers and the mineral or organic compounds present in solid and/or liquid waste may raise phosphorus (P) content and increase soil P saturation. The degree of phosphorus saturation (DPS) is a good indicator of potential P loss from agricultural soils. The purpose of this study was to calculate the DPS of samples from an Oxisol amended for 5 years with biosolids and mineral fertilizer. DPS was calculated based on P, iron, and aluminum extracted by ammonium oxalate and oxalic acid (DPSox) or by Mehlich-1 solution (DPSM1). Treatments included NPK mineral fertilization (175 kg ha?1 of P), B1?=?19.02 t ha?1 of biosolids (350 kg ha?1 of P), B2?=?38.17 t ha?1 of biosolids (703 kg ha?1 of P), B3?=?76.26 t ha–1 of biosolids (1,405 kg ha?1 of P), and a control (no P added). Water-extractable P (WEP) was also measured. Critical levels of DPSox and DPSM1 (21 and 24 %, respectively) were only achieved in the topsoil (0–0.1 m) at the highest biosolid dose. Concentration of WEP was positively correlated to DPSox and DPSM1. The DPSM1 method may be an alternative to DPSox for assessing the environmental risk of P loss from soil into surface runoff.  相似文献   
104.
This paper presents large eddy simulation of turbulent flow in a meandering open channel with smooth wall and rectangular cross-section. The Reynolds number based on the channel height is 40,000 and the aspect ratio of the cross-section is 4.48. The depth-averaged mean stream-wise velocity agree well to experimental measurements. In this specific case, two interacting cells are formed that swap from one bend to the other. Transport and mixing of a pollutant is analysed using three different positions of release, e.g. on the inner bank, on the outer bank and on the centre of the cross section. The obtained depth-average mean concentration profiles are reasonably consistent with available experimental data. The role of the secondary motions in the mixing processes is the main focus of the discussion. It is found that the mixing when the scalar is released on the centre of the cross-section is stronger and faster than the mixing of the scalar released on the sides. When the position of release is close to a bank side, the mixing is weaker and a clear concentration of scalar close to the corresponding side-wall can be observed in both cases.  相似文献   
105.
Regional Environmental Change - Better understanding the pathways through which future socioeconomic changes might influence land use and land cover changes (LULCCs) is a crucial step in accurately...  相似文献   
106.
Environmental Science and Pollution Research - Ultra-violet C (UV-C) treatment is commonly used in sterilization processes in industry, laboratories, and hospitals, showing its efficacy against...  相似文献   
107.
Journal of Material Cycles and Waste Management - Understanding the chemical and mineralogical characteristics of bottom ash (BA) containing Potentially Toxic Elements (PTEs, e.g., As, Cd, Co, Cu,...  相似文献   
108.
Abstract

In pursuit of coping mechanisms for the challenges of sustainable manufacturing, systematic methods have been developed to allow engineers to improve the ratio between products’ utility and environmental impact. These necessary efforts remain however limited if the surrounding production and consumption practices are not called into question at the same time. This article introduces open source product development as a potential approach for unlocking the limits of existing sustainable product design practices and to lead towards alternative and eco-efficient production and consumption practices termed as participative production. First, it discusses the potential advantages of this emerging practice in terms of environmental sustainability. Second, it provides a screened qualitative environmental analysis of 18 exemplary open source hardware products. Specific sustainable design principles implemented by these products are highlighted and discussed in order to identify challenges for further common research in the field of open source and sustainable product development.  相似文献   
109.
The ecosystem services framework is receiving increasing attention in the fields of policy and research. The assessment of human attitudes and perceptions regarding ecosystem services has been proposed as a promising tool for addressing complex problems associated with environmental change, particularly in the context of cultural landscapes. Transhumance is not only a farming practice responsible for shaping cultural landscapes but also an adaptive strategy based on mobility that may represent a useful approach to overcoming the growing challenges posed by accelerated environmental change. A socio-cultural valuation of ecosystem services associated with the Conquense Drove Road, one of the major transhumant networks still in use in Mediterranean Spain, was conducted via the distribution of questionnaires to 416 local residents and visitors to capture their perceptions regarding the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services in question were perceived as declining, with the exception of those associated with recreation, scientific knowledge and environmental education. This study revealed that perceptions regarding the value of ecosystem services differed among respondents, depending on their age, place of origin and gender. Several methodological issues, as well as the implications of socio-cultural valuation for policy making, are also discussed here.  相似文献   
110.
Although fish is a healthy alternative for meat, it can be a vehicle for mercury (Hg), including in its most toxic organic form, methylmercury (MeHg). The objective of the present study was to estimate the risk to human health caused by the consumption of sushi and sashimi as commercialized by Japanese food restaurants in the city of Campinas (SP, Brazil). The total Hg content was determined by atomic absorption spectrometry with thermal decomposition and amalgamation, and the MeHg content calculated considering that 90% of the total Hg is in the organic form. The health risk was estimated from the values for the provisional tolerable weekly ingestion (PTWI) by both adults and children. The mean concentrations for total Hg were: 147.99, 6.13, and 3.42 µg kg?1 in the tuna, kani, and salmon sushi samples, respectively, and 589.09, 85.09, and 11.38 µg kg?1 in the tuna, octopus and salmon sashimi samples, respectively. The tuna samples showed the highest Hg concentrations. One portion of tuna sashimi exceeded the PTWI value for MeHg established for children and adults. The estimate of risk for human health indicated that the level of toxicity depended on the type of fish and size of the portion consumed.  相似文献   
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