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1.
Urbanization and mass movement of the population from rural areas and small cities to megacities have led to environmental, economic, and social problems in Iran. In dealing with these challenges, assessing resource and environmental carrying capacity (RECC) is considered an effective method to leverage space and capital to achieve sustainable development. This study aimed to rank the provincial RECC in Iran. Toward this purpose, environmental indices were generated from remotely sensed and statistical census data. Then, the provinces were scored in terms of environmental, economic, and infrastructural carrying capacities, and RECC using the mean variance analysis method. Results demonstrated that in most areas, there is no relationship between economic and infrastructural capacities and development. Statistically, a correlation coefficient of −0.53 between economic and environmental carrying capacities indicated excessive use of environmental capacities. Moreover, the spatial distribution pattern of environmental, economic, and infrastructural carrying capacity was entirely heterogeneous between the provinces; there was a northeast–southwest pattern in terms of infrastructural capacity and an economic pattern from north to south. The distribution pattern of RECC is most consistent with the environmental capacity, pointing at the high weight of the indicators of the RECC model. In conclusion, this research offers a new vision for policymakers and provides a theoretical and applicable framework for implementing sustainable strategies in land-use planning. It is recommended that the RECC concept and tools can be used not only for planning but also for measuring the efficiency of spatial development programs and establishing land balances in the region.  相似文献   
2.
Efficient and robust photocatalysts for environmental pollutants removal with outstanding stability have great significance. Herein, we report a kind of three dimensional (3D) photocatalyst presented as Z-scheme heterojunction, which combining TiO 2 and Zn x Cd 1- x S with graphene aerogel to contrast TiO 2 -Zn x Cd 1- x S graphene aerogel (TSGA, x = 0.5) through a moderate hydrothermal process. The as-prepared Z-scheme TSGA was used to remove aqueous Cr(VI) via a synergistic effect of adsorption and visible light photocatalysis. The adsorption equilibrium can be reached about 40 min, then after about 30 min irradiation under visible light (wavelength ( λ) > 420 nm) the removal rate of Cr(VI) almost reached 100%, which is much better than the performance of pristine TiO 2 and Zn 0.5 Cd 0.5 S, as well as TiO 2 graphene aerogel (TGA) and Zn 0.5 Cd 0.5 S graphene aerogel (SGA). The virulent Cr(VI) was reduced to Cr(III) with hypotoxicity after photocatalysis on TSGA, meanwhile the as-synthesized TSGA presented a good stability and reusability. The reduced graphene oxide (rGO) sheets between TiO 2 and Zn 0.5 Cd 0.5 S played a role as charge transfer mediator, promoting the photoinduced electrons transfer and photocatalysis ability of TSGA was enhanced significantly. Hence,such photocatalyst exhibits a potential application on removing heavy metals with high efficiency and stability from polluted aqueous environment.  相似文献   
3.
基于气相色谱-质谱联用(GC-MS)法结合固相萃取(SPE)前处理技术,建立了水中4种除草剂氯草定、阿特拉津、乙草胺和异丙甲草胺残留的分析方法,于2018年春(4、5月)、秋(9、10月)和冬(1、3月)季对太湖流域望虞河西岸九里河水体中4种除草剂的污染现状进行调查分析。结果表明,4种除草剂的加标回收率为71. 2%~108%,RSD均10%,方法检出限为3. 5~6. 0 ng/L。九里河水体中氯草定、阿特拉津、乙草胺和异丙甲草胺4种除草剂质量浓度分别为未检出~0. 025 7,0. 019 1~1. 19,未检出~0. 026 0和未检出~0. 094 3μg/L。4种除草剂中阿特拉津最高值接近《地表水环境质量标准》(GB 3838—2002)限值,其他3种其值较低,氯草定首次在太湖流域水体中检出。  相似文献   
4.
Veterinary antibiotics used in agriculture can be introduced into the environment through land application of animal manure, accumulating in soils and groundwaters and posing a significant risk to human health and animal well-being. As the analysis of tetracyclines in soil is challenging due to their strong interaction with soil minerals and organic carbon, the objective of this study was to develop a reliable and reproducible method for quantitative analysis of chlortetracycline and oxytetracycline, and their respective metabolites in soils. A method based on pressurized liquid extraction (PLE) with in-cell clean-up was developed for the extraction of chlortetracycline and oxytetracycline and four likely metabolites from a set of four soils. Optimized conditions included a cell size of 22?mL, soil loading of 5?g, pH of 8.0, methanol:water ratio of 3:1, 50?°C, and two cycles. Soil extracts were analysed by high-performance liquid chromatography (HPLC) coupled with ion trap mass spectrometry (MS). Recoveries of seven tetracyclines from soil ranged from 41% to 110%. The limits of detection for tetracyclines were 0.08–0.3 µg g?1 soil, and intra- and inter-day variation ranged from 0.12–0.34%. The proposed PLE method is suitable for quantification of tetracyclines in agricultural soils at typical concentrations expected in contaminated environments.  相似文献   
5.
The ozone initiated oxidation of 1,3,7-trimethylxanthine (caffeine), commonly found in wastewaters as model compound is reported using cerium (Ce)/titanium dioxide (TiO2) as catalyst. The effect of pH and loading of ceria on titania were investigated. Effect of reaction conditions on degradation of caffeine based on their pseudo first-order rate constants were compared. The combination of catalyst Ce-TiO2 and ozone aeration significantly enhanced the degradation of caffeine compared to uncatalysed ozonation. The oxidation of caffeine ensued via the free radical mechanism, through enhanced ozone decomposition into OH radicals. Ce/TiO2(0.5?wt%) showed good activity in degradation of caffeine at pH 6, in both natural stream and river water samples showing about 60% total organic carbon removal in 2?h ozonation period. Using liquid chromatography-mass spectroscopy, degradation products were analysed. A reaction intermediate and one final product were positively identified. Nano-catalysts with different loadings of Ce on TiO2 synthesized by sol-gel route were characterized by scanning electron microscope, transmission electron microscopy, BET and powder X-ray diffraction spectrum techniques. The results showed that the material retained a highly ordered mesoporous structure and possessed large surface area.  相似文献   
6.
A nutrient loss reduction strategy is necessary to guide the efforts of improving water quality downstream of an agricultural watershed. In this study, the effectiveness of two winter cover crops, namely cereal rye and annual ryegrass, is explored as a loss reduction strategy in a watershed that ultimately drains into a water supply reservoir. Using a coupled optimization-watershed model, optimal placements of the cover crops were identified that would result in the tradeoffs between nitrate-N losses reduction and adoption levels. Analysis of the 10%, 25%, 50%, and 75% adoption levels extracted from the optimal tradeoffs showed that the cover crop placements would provide annual nitrate-N loss reductions of 3.0%–3.7%, 7.8%–8.8%, 15%–17.5%, and 20.9%–24.3%, respectively. In addition, for the same adoption levels (i.e., 10%–75%), sediment (1.8%–17.7%), and total phosphorus losses (0.8%–8.6%) could be achieved. Results also indicate that implementing each cover crop on all croplands of the watershed could cause annual water yield reduction of at least 4.8%, with greater than 28% in the months of October and November. This could potentially be detrimental to the storage volume of the downstream reservoir, especially in drought years, if cover crops are adopted in most of the reservoir's drainage area. Evaluating water yield impacts, particularly in periods of low flows, is thus critical if cover crops are to be considered as best management practices in water supply watersheds.  相似文献   
7.
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
8.
Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.  相似文献   
9.
Every 2 years, the conservation community comes together at The Society for Conservation Biology's International Congress for Conservation Biology (ICCB) to share new developments in conservation science and practice. Publication of findings presented at conferences in scientific journals adds to the permanent record and helps increase the potential impact of the work presented. However, quantitative research on publication rates for meetings relevant to conservation is lacking. For the 25th ICCB, (Auckland, New Zealand in 2011), we examined study publication rates and presenter demographics, recorded titles, number of authors, presenter affiliations, gender, country of the study region, publication status, and elapsed time between presentation and publication. Of the 980 contributions (782 talks and 198 posters), 587 (60%) were published as peer-reviewed journal articles or book chapters. Mean time to publication was 13.7 months for all presentation abstracts and 21.3 months excluding abstracts with corresponding articles that were published before the meeting. The gender breakdown of presenters was almost even (53% male, 47% female), but representation of the countries where the presenting authors were based was skewed. The political units with the most contributions were by far the United States, Australia, New Zealand, and the United Kingdom. Presenters based in 16 different English-speaking countries made up 74% of the total sample, but this did not influence the likelihood of their abstract leading to a publication. Examination of conference presenters and publication of their presentations is useful to identify biases and potential challenges that need to be addressed to make conference communications permanent and increase their reach beyond conference attendees.  相似文献   
10.
为全面认识驾驶人行为及风险感知并分析行为成因,从驾驶人生理因素着手,从驾驶人视力、阻塞性睡眠呼吸暂停综合征和肌肉骨骼疾患3个方面梳理国内外驾驶人行为及风险感知的研究成果与研究不足。研究结果表明:驾驶人的生理疾病对其驾驶能力和危险感知存在显著影响;生理疾病严重程度与异常驾驶行为中的一般性失误、危险性失误行为之间具有显著正相关关系,疾病严重程度越高,出行失误行为的频率越高;之后可从理论和实验两方面着手,针对驾驶人的不同属性进行研究。  相似文献   
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