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271.
272.
Tickner JA Geiser K Coffin M 《Environmental science and pollution research international》2005,12(2):115-123
- Sustainable chemistry - Section editors:
Klaus Günter Steinhäuser, Steffi Richter, Petra Greiner, Jutta Penning, Michael AngrickBackground, Aim and Scope Recent developments in European chemicals policy, including the Registration, Evaluation and Authorization of Chemicals (REACH) proposal, provide a unique opportunity to examine the U.S. experience in promoting sustainable chemistry as well as the strengths and weaknesses of existing policies. Indeed, the problems of industrial chemicals and limitations in current regulatory approaches to address chemical risks are strikingly similar on both sides of the Atlantic. We provide an overview of the U.S. regulatory system for chemicals management and its relationship to efforts promoting sustainable chemistry. We examine federal and state and examine lessons learned from this system that can be applied to developing more integrated, sustainable approaches to chemicals management.Main Features There is truly no one U.S. chemicals policy, but rather a series of different un-integrated policies at the federal, regional, state and local levels. While centerpiece U.S. Chemicals Policy, the Toxic Substances Control Act of 1976, has resulted in the development of a comprehensive, efficient rapid screening process for new chemicals, agency action to manage existing chemicals has been very limited. The agency, however, has engaged in a number of successful, though highly underfunded, voluntary data collection, pollution prevention, and sustainable design programs that have been important motivators for sustainable chemistry. Policy innovation in the establishment of numerous state level initiatives on persistent and bioaccumulative toxics, chemical restrictions and toxics use reduction have resulted in pressure on the federal government to augment its efforts.Results and Conclusions It is clear that data collection on chemical risks and phase-outs of the most egregious chemicals alone will not achieve the goals of sustainable chemistry. These alone will also not internalize the cultural and institutional changes needed to ensure that design and implementation of safer chemicals, processes, and products are the focus of the future. Thus, a more holistic approach of ‘carrots and sticks’ that involves not just chemical producers but those who use and purchase chemicals is necessary. Some important lessons of the US experience in chemicals management include: (1) the need for good information on chemicals flows, toxic risks, and safer substances.; (2) the need for comprehensive planning processes for chemical substitution and reduction to avoid risk trade-offs and ensure product quality; (3) the need for technical and research support to firms for innovation in safer chemistry; and (4) the need for rapid screening processes and tools for comparison of alternative chemicals, materials, and products. 相似文献
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275.
Joel S. Brown 《Behavioral ecology and sociobiology》1988,22(1):37-47
Summary A technique for using patch giving up densities to investigate habitat preferences, predation risk, and interspecific competitive relationships is theoretically analyzed and empirically investigated. Giving up densities, the density of resources within a patch at which an individual ceases foraging, provide considerably more information than simply the amount of resources harvested. The giving up density of a forager, which is behaving optimally, should correspond to a harvest rate that just balances the metabolic costs of foraging, the predation cost of foraging, and the missed opportunity cost of not engaging in alternative activities. In addition, changes in giving up densities in response to climatic factors, predation risk, and missed opportunities can be used to test the model and to examine the consistency of the foragers' behavior. The technique was applied to a community of four Arizonan granivorous rodents (Perognathus amplus, Dipodomys merriami, Ammospermophilus harrisii, and Spermophilus tereticaudus). Aluminum trays filled with 3 grams of millet seeds mixed into 3 liters of sifted soil provided resource patches. The seeds remaining following a night or day of foraging were used to determine the giving up density, and footprints in the sifted sand indicated the identity of the forager. Giving up densities consistently differed in response to forager species, microhabitat (bush versus open), data, and station. The data also provide useful information regarding the relative foraging efficiencies and microhabitat preferences of the coexisting rodent species. 相似文献
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277.
Summary The prediction that mothers should invest more in sons than daughters was briefly examined in American bison (Bison bison) by Wolff (1988). He concluded that (a) male calves suckle more than females, (b) cows that had previously produced sons were more likely to be barren, and (c) cows that had male calves became estrous later in the year than other cows. In this paper we present data from two long term studies at different sites to show that Wolff's conclusions are equivocal at best and difficult to reconcile with predictions of the hypothesis because of questionable methods and assumptions.
Offprint requests to: W.C.H. Green 相似文献
278.
A stakeholder driven process to reduce vulnerability to climate change in Hermosillo,Sonora, Mexico 总被引:1,自引:0,他引:1
Hallie Eakin Victor Magaña Joel Smith José Luis Moreno José Maria Martínez Osvaldo Landavazo 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):935-955
While there is a growing body of knowledge on potential impacts of climate change on water availability, there has been much
less empirical research on exploring the viability of particular adaptation options. The participation of stakeholders in
defining appropriate adaptation strategies is increasingly recognized as a critical element in the translation of climate
change impact research into effective actions to reduce future vulnerability, yet the process by which stakeholders are included
in such initiatives is not well-defined. This article presents the results of a pilot project in which a participatory approach
was employed to identify and evaluate adaptation options to climate change scenarios for Sonora’s capital city, Hermosillo.
In an iterative process, stakeholders representing different water users and managers in the city met to discuss climate change
scenarios, identify specific adaptation options, and evaluate a subset of options for possible future implementation. This
process enabled the focus of the investigation on those adaptations that addressed not only concerns with the potential future
impacts of climate change but also the immediate and pressing concerns about development patterns and water use in the city.
Two of the adaptations to climate change identified by stakeholders would also reduce energy demand. The simplicity of the
approach makes it a feasible model for adaptation initiatives in other regions of Mexico and in other countries in Latin America.
相似文献
Osvaldo LandavazoEmail: |
279.
Complexation of the antibiotic tetracycline with humic acid 总被引:10,自引:0,他引:10
The effect of solution chemistry and sorbate-to-sorbent ratio on the interaction of the antibiotic tetracycline with Elliott soil humic acid (ESHA) was investigated using equilibrium dialysis and FITEQL modeling. Tetracycline speciation strongly influenced its sorption to ESHA. Sorption was strongly pH-dependent with a maximum around pH 4.3, and competition with H+ and electrolyte cation (Na+) was evident. The pH-dependent trend was consistent with complexation between the cationic/zwitterionic tetracycline species and deprotonated sites in ESHA (mainly carboxylic functional groups). Modification of ESHA by Ca2+ addition increased tetracycline sorption suggesting that ternary complex formation (ESHA-metal-tetracycline) may be important at higher concentrations of multivalent metal cations. The macroscopic data (pH-envelope and sorption isotherms) were successfully modeled using a discrete logK function with the FITEQL 4.0 chemical equilibrium program indicating that ESHA-tetracycline interaction could be reasonably represented as complex formation of a monoacid with discrete sites in humic acid. Sorption-desorption hysteresis was observed; both sorption and desorption isotherms were well described by the Freundlich equation. 相似文献
280.
Ford Scott Alan Persson Joel Jepsen Martin Rudbeck Mertz Ole 《Regional Environmental Change》2022,22(4):1-14
Regional Environmental Change - Climate change has severe impacts on the livelihoods of West-African communities with the floods of the late 2000s and early 2010s serving as factual evidence.... 相似文献