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891.
Benjamin Hofmann Karin Ingold Christian Stamm Priska Ammann Rik I. L. Eggen Robert Finger Samuel Fuhrimann Judit Lienert Jennifer Mark Chloe McCallum Nicole Probst-Hensch Ueli Reber Lucius Tamm Milena Wiget Mirko S. Winkler Lucca Zachmann Sabine Hoffmann 《Ambio》2023,52(2):425
Calls for supporting sustainability through more and better research rest on an incomplete understanding of scientific evidence use. We argue that a variety of barriers to a transformative impact of evidence arises from diverse actor motivations within different stages of evidence use. We abductively specify this variety in policy and practice arenas for three actor motivations (truth-seeking, sense-making, and utility-maximizing) and five stages (evidence production, uptake, influence on decisions, effects on sustainability outcomes, and feedback from outcome evaluations). Our interdisciplinary synthesis focuses on the sustainability challenge of reducing environmental and human health risks of agricultural pesticides. It identifies barriers resulting from (1) truth-seekers’ desire to reduce uncertainty that is complicated by evidence gaps, (2) sense-makers’ evidence needs that differ from the type of evidence available, and (3) utility-maximizers’ interests that guide strategic evidence use. We outline context-specific research–policy–practice measures to increase evidence use for sustainable transformation in pesticides and beyond. 相似文献
892.
Antibiotic formulation effluent is well known for its important contribution to environmental pollution due to its fluctuating and recalcitrant nature. In the present study, the chemical treatability of penicillin formulation effluent (average filtered COD(o)=830 mg/l; average soluble COD(o)=615 mg/l; pH(o)=6.9) bearing the active substances penicillin Amoxicillin Trihydrate (C(16)H(19)N(3)O(5)S.3H(2)O) and the beta-lactamase inhibitor Potassium Clavulanate (C(8)H(8)KNO(5)) has been investigated. For this purpose, the penicillin formulation effluent was subjected to ozonation (applied ozone dose=2500 mg/(lxh)) at varying pH (2.5-12.0) and O(3)+H(2)O(2) (perozonation) at different initial H(2)O(2) concentrations (=2-40 mM) and pH 10.5. According to the experimental results, the overall Chemical Oxygen Demand (COD) removal efficiency varied between 10 and 56% for ozonation and 30% (no H(2)O(2)) and 83% (20 mM H(2)O(2)) for the O(3)+H(2)O(2) process. The addition of H(2)O(2) improved the COD removal rates considerably even at the lowest studied H(2)O(2) concentration. An optimum H(2)O(2) concentration of 20 mM existed at which the highest COD removal efficiency and abatement kinetics were obtained. The ozone absorption rate ranged between 53% (ozonation) and 68% (perozonation). An ozone input of 800 mg/l in 20 min was sufficient to achieve the highest BOD(5)/COD (biodegradability) ratio (=0.45) and BOD(5) value (109 mg/l) for the pre-treated penicillin formulation effluent. After the establishment of optimum ozonation and perozonation conditions, mixtures of synthetic domestic wastewater+raw, ozonated and perozonated penicillin formulation effluent were subjected to biological activated sludge treatment at a food-to-microorganisms (F/M) ratio of 0.23 mg COD/(mg MLSSxd), using a consortium of acclimated microorganisms. COD removal efficiencies of the activated sludge process were 71, 81 and 72% for pharmaceutical wastewater containing synthetic domestic wastewater mixed with either raw, ozonated or perozonated formulation effluent, respectively. The ultimate COD value obtained after 24-h biotreatment of the synthetic domestic wastewater+pre-ozonated formulation effluent mixture was around 100 mg/l instead of 180 mg/l which was the final COD obtained for the wastewater mixture containing raw formulation effluent, indicating that pre-ozonation at least partially removed the non-biodegradable COD fraction of the formulation effluent. 相似文献
893.
Alam R Chowdhury MA Hasan GM Karanjit B Shrestha LR 《Waste management (New York, N.Y.)》2008,28(6):1088-1097
Solid waste management (SWM) services have consistently failed to keep up with the vast amount of solid waste produced in urban areas. There is not currently an efficient system in place for the management, storage, collection, and transportation of solid waste. Kathmandu City, an important urban center of South Asia, is no exception. In Kathmandu Metropolitan City, solid waste generation is predicted to be 1091 m(3)/d (245 tons/day) and 1155 m(3)/d (260 tons/day) for the years 2005 and 2006, respectively. The majority (89%) of households in Kathmandu Metropolitan City are willing to segregate the organic and non-organic portions of their waste. Overall collection efficiency was 94% in 2003. An increase in waste collection occurred due to private sector involvement, the shutdown of the second transfer station near the airport due to local protest, a lack of funding to maintain trucks/equipment, a huge increase in plastic waste, and the willingness of people to separate their waste into separate bins. Despite a substantial increase in total expenditure, no additional investments were made to the existing development plan to introduce a modern disposal system due to insufficient funding. Due to the lack of a proper lining, raw solid waste from the existing dumping site comes in contact with river water directly, causing severe river contamination and deteriorating the quality of the water. 相似文献
894.
Remediation of contaminated land and groundwater is of common international concern. The context and approach taken to the problem are, however, country-specific. A survey of remedial activity occurring within England and Wales over the period 1996-1999 was commissioned by the Environment Agency (for England and Wales) to establish a baseline against which future trends in remedial activity could be judged. This paper: explains the context of contaminated land and groundwater remediation in England and Wales (Britain); provides an overview of the 1996-1999 survey of remedial activity, discussing its findings within its legislative and institutional context; and, discusses the survey results of significance to the management of contaminated land and groundwater internationally. The survey obtained specific data from 367 remediated sites supplemented by general data from a further 1189 contaminated (not necessarily remediated) sites. The survey aimed to be, and was indicative of remediation practice, and did not seek to identify every remediation scheme operating. Previous anecdotal evidences were generally confirmed. Civil engineering-based techniques dominated and were used at 94% of sites with in situ techniques (predominantly vapour extraction-based) on 16% and ex situ on just 5%. Although disposal to landfill was dominant and occurred at over 80% of sites, integrated use of multiple techniques was common. Remediation was predominantly of soil (rather than water), development-based, designed to protect human health and reflected national development-led and 'suitable for use' policies. Lessons of international relevance from the survey and general British experience are drawn concerning remediation technique selection, regulatory and financial support of innovative remediation techniques and demonstration sites, competent use of risk-based approaches to allow pragmatic remediation and effective use of quality guidelines, need for effective guidance to highlight water quality issues, the necessity of post remediation monitoring to prove remediation effectiveness and the keeping of remediation databases. 相似文献
895.
On the Solovetskiye Islands, subtundra forests and forest-tundra crooked forests are considered to be zonal biocenoses, as this region is intersected by the 12°C isotherm for July, which marks the boundary between the northern taiga and forest-tundra zones in northern Europe. The formation of extrazonal tundras on the islands is attributed to the cooling effect of the sea and the prevalence of cold northeasterly winds in the growing period. Herbaceous and herb-bilberry forests similar to their middle-taiga counterparts develop in this region due to a convective heat flow anomaly of high intensity (up to 40–50 W/m2). The phenomenon provides evidence for the existence of an active heat source in the crust under the archipelago. This source is probably a diapir fold involving the upward movement of the mantle. 相似文献
896.
G. W. Uetz William J. McClintock Douglas Miller Elizabeth I. Smith Kristina K. Cook 《Behavioral ecology and sociobiology》1996,38(4):253-257
Males of the brush-legged wolf spider Schizocosa ocreata (Hentz) have conspicuously decorated forelegs used in courtship and agonistic displays. Approximately one in five juvenile
males has a missing or regenerating foreleg, and regeneration of a leg lost during development usually results in the absence
of a decorative tuft on that leg. The subsequent asymmetry in this male secondary character significantly decreases success
in both courtship of females and male-male agonistic interactions. Experimental removal of tufts from one leg of previously
successful symmetric males produces similar results. As a test for concomitant behavioral effects, female spiders were shown
video images of a courting male with symmetric tufts and the same video image altered to have asymmetric tufts. Female receptivity
to the asymmetric video image was lower. In contrast to fluctuating asymmetry resulting from developmental instability, leg
tuft asymmetry in S. ocreata most likely arises from a single event during ontogeny – possibly leg loss from an aggressive or predator encounter – and
may serve as a quality indicator in female mate choice.
Received: 27 July 1995/ Accepted after revision: 19 November 1995 相似文献
897.
T.I. Khan 《The Environmentalist》1997,17(4):283-287
Director of environmental studies at the Indira Gandhi Centre for Human Ecology, Environmental and Population Studies at the University of Rajasthan. This paper describes the biodiversity in the north-western Indian State of Rajasthan, its relationship with the environment and the existing human and livestock populations. As the biodiversity is depleting in this area due to zoogenic and anthropogenic reasons, certain pragmatic conservation strategies are advocated. The north-western part of India is occupied by a desert ecosystem, the Thar Desert. Animal husbandry is the major livelihood in the region, followed by agriculture. The vegetation, which is predominantly xerophytic and quite sparse, occurs in great variety. Six hundred and eighty-two plant species and 390 animal species have been identified from the Thar Desert. Many plant and animal species have become endangered due to zoogenic and anthropogenic activities. Plants such as Calligonum polygonoides, Tecomella undulata and Prosopis cineraria urgently require conservation. 相似文献
898.
I. Nishiumi Satoshi Yamagishi Hiromi Maekawa Chikashi Shimoda 《Behavioral ecology and sociobiology》1996,39(4):211-217
In many polygynous animals, parents invest more heavily in individual sons than in daughters. However, it is unclear if these
differences in investment are a consequence of sex differences in the demand of offspring related to sexual size dimorphism
or a consequence of parental manipulation. Here, we report on parental food delivery frequency in relation to brood size and
brood sex ratio in a wild population of polygynous great reed warblers Acrocephalus arundinaceus. We used the polymorphic microsatellite loci on the Z chromosome to sex chicks. We found that paternal feeding frequency
(times/h per nest) increased not with brood size, but with the proportion of males in the brood, although the demand per nest
was more closely related to brood size than to brood sex ratio. Additionally, the increase in rate of paternal feeding frequency
in relation to the brood sex ratio was much higher than the increase in rate of nestling food demands. Maternal feeding frequency
was independent of both brood size and brood sex ratio. These results strongly suggest that fathers preferentially invest
in their sons. We propose that parents can afford sex-biased parental care in animals in which food provisioning is enough
for all offspring to survive.
Received: 22 January 1996/Accepted after revision: 30 June 1996 相似文献
899.
It has been suggested that shapes of burned areas resulting from fires spreading under uniform fuel and meteorological conditions may be described as ellipses, double ellipses, or ovoids. The adequacy of these shapes (together with simulation outputs) as bases for fire spread models was tested by finding the best fits of each shape to maps of experimental fires and comparing the results with fits given by a rectangle (an unlikely fire shape). Each of the models (ellipse, double ellipse, ovoid, simulation model, and even the rectangle) provided adequate approximations to the fire contours used in the tests. The parameter trends found implied that the fires examined tended to become more nearly elliptical in shape and to have higher eccentricity as they grew. 相似文献
900.