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751.
The Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) have recently launched themselves as the UN-sanctioned instrument for conserving nature. They seek to establish themselves as the authority in this field alongside the well-known Intergovernmental Panel on Climate Change in climate science. Quickly following or even before recent publication of their conceptual framework in two biology journals, they were already underway building upon it. This headlong push, we believe, is ill advised. We show how the framework is unsound as a foundation for further work—in a number of ways and perhaps even by its authors’ own lights. It is therefore urgent that the IPBES thoroughly and thoughtfully reconsider their framework before too much effort is wasted.  相似文献   
752.
Ground and surface water selenium (Se) contamination is problematic throughout the world, leading to harmful impacts on aquatic life, wildlife, livestock, and humans. A groundwater reactive transport model was applied to a regional‐scale irrigated groundwater system in the Lower Arkansas River Basin in southeastern Colorado to identify management practices that remediate Se contamination. The system has levels of surface water and groundwater Se concentrations exceeding the respective chronic standard and guidelines. We evaluate potential solutions by combining the transport model with an assessment of the cost to employ those practices. We use a framework common in economics and engineering fields alike, the Pareto frontier, to show the impact of four different best management practices on the tradeoffs between Se and cost objectives. We then extend that analysis to include institutional constraints that affect the economic feasibility associated with each practice. Results indicate that although water‐reducing strategies have the greatest impact on Se, they are the hardest for farmers to implement given constraints common to western water rights institutions. Therefore, our analysis shows that estimating economic and environmental tradeoffs, as is typically done with a Pareto frontier, will not provide an accurate picture of choices available to farmers where institutional constraints should also be considered.  相似文献   
753.
Communities in Phoenix are confronted with numerous challenges that adversely affect human health and safety, with disproportionate impacts on low-income communities. While some challenges are being addressed at the city level, new alliances at the neighbourhood level are initiating community development programmes and projects. This article reports on an intervention study carried out in collaboration with community representatives, city staff, and non-profit organisations to mitigate adverse effects of urban sprawl in the Sky Harbour Neighbourhood in Phoenix. Participatory research was conducted to design and test a tree and shade intervention. Challenges associated with navigating community desires and broader principles of sustainable development are discussed. The study offers a replicable and adaptable intervention research design aimed at empowering communities to meet urban challenges.  相似文献   
754.
This paper presents the results of ethnographic research conducted with several environmental justice (EJ) organisations in Latino communities of Los Angeles, California. Traditional EJ politics revolves around research and advocacy to reduce discriminatory environmental exposures, risks, and impacts. However, I argue that in recent years there has been a qualitative change in EJ politics, characterised by four main elements: (1) a move away from the reaction to urban environmental “bads” (e.g. polluting industries) in the city towards a focus on the production of nature in the city; (2) strategies that are less dependent on the legal, bureaucratic, and technical “regulatory route”; (3) the formation of a distinctive “Latino environmental ethic” that offers a more complex consideration of the place of race in EJ organising; and (4) a spatial organisation of EJ politics that moves away from hyperlocal, vertical organisation towards diversified city-wide networks that include EJ organisations, mainstream environmental groups, nonprofits, foundations, and entrepreneurs. This shift in EJ movement politics is shaped by broader political-economic changes, including the shift from post-Fordist to neoliberal and now green economy models of urban development; the influence of neoliberal multiculturalism in urban politics; and the increasingly prominent role of Latinos in city, state, and national politics. New spaces of Latino EJ also reflect the ambitions of Los Angeles as a global city, with urban growth increasingly framed in an international discourse of sustainability that combines quality of life, environmental, and economic development rationales.  相似文献   
755.
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.  相似文献   
756.
Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree–mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics.  相似文献   
757.
The objective of this study was to evaluate the effects of early life stage triclosan (5-chloro-2-(2,4, dichlorophenoxy)phenol, TCS) exposure on hatching, development, and survival in the fathead minnow, Pimephales promelas. Embryonic minnows were exposed to TCS (50 and 100 µg L?1) for 10 days followed by 6 weeks depuration. Mortality and morphological deformities were recorded and quantified during exposure and at the end of depuration. No significant effects on embryonic survival, time to reach the eyed stage, or hatching were found. However, at the conclusion of the depuration period, survival was significantly reduced in TCS exposed fish depending on the concentration. Visual inspection of the exposed fish suggests that mortality is related to spinal deformities, emaciation, and reduced foraging ability. Triclosan exhibits deleterious effects in fish at lower concentrations over longer durations than previously reported. Further, mortality in exposed fish 6 weeks after exposure demonstrates the need for various exposure assays to evaluate effects of TCS.  相似文献   
758.
To estimate the variability of pesticide residue levels present in cauliflower units, a total of 142 samples were collected from a field trial of a cooperative farmer, and 120 samples were collected from different market places in Thessaloniki, Greece. The collected samples were extracted using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction technique, and the residues were determined by liquid chromatography–tandem mass spectrometry. The developed method was validated by evaluating the accuracy, precision, linearity, limit of detection (LOD), and limit of quantification (LOQ). The average recoveries for all the analytes, derived from the data of control samples fortified at 0.01, 0.05, 0.1, and 0.2 mg/kg, ranged from 74 to 110% with a relative standard deviation of ≤8%. The correlation coefficient (R2) was ≥0.997 for all the analytes using matrix-matched calibration standards. The LOD values ranged from 0.001 to 0.003 mg/kg, and the LOQ was determined at 0.01 mg/kg for all the sought analytes. The matrix effect was found to be at a considerable level, especially for cypermethrin and deltamethrin, amounting to +90% and +145%, respectively. For the field samples, the unit-to-unit variability factors (VFs) calculated for cypermethrin and deltamethrin were 2.38 and 2.32, respectively, while the average VF for the market basket samples was 5.11. In the market basket samples, residues of cypermethrin, deltamethrin, chlorpyrifos, and indoxacarb were found at levels ≥LOQ and their respective VFs were 7.12, 5.67, 5.28, and 2.40.  相似文献   
759.
This paper reports on recycling of industrial wastes (three pharmaceutical industrial sludges) into environmental friendly value-added materials. Stabilization/Solidification (S/S or bricks) process was applied to make a safer way for the utilization of pharmaceutical waste. The additives in this study include binders (cement, lime and bentonite) and strengthening material (pulverized fuel ash (PFA), silica fume and quarry dust) was used at different compositions. Bricks were cured for 28 days, and the following analysis-like compressive strength, leachability of heavy metals, mineralogical phase identity by X-ray diffraction (XRD) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and thermal behaviour by thermogravimetric-differential thermal analysis (TG-DTA) had done. All the bricks were observed to achieve the standard compressive strength as required for construction according to BIS standards. Metal concentration in the leachate has reached the dischargeable limits according to Brazilian standards. Results of this study demonstrate that production of bricks is a promising and achievable productive use of pharmaceutical sludge.  相似文献   
760.
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