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1.
陈彩虹 《绿色科技》2021,(5):219-222,236
生态文明教育是形成生态意识和生态行为的重要途径,是影响生态文明建设进程的重要因素。理想的生态文明教育系统是包含家庭教育、学校教育、企业教育和社会教育四大分系统在内的、拥有完整功能和流程的服务系统;各分系统在时间维度上相互衔接、在空间维度上相互独立,并在不同时空发挥各自的作用。但现行的生态文明教育系统尚未意识到其服务属性,在自我定位、系统设计和流程安排上仍按照传统教育模式进行,不利于形成节约资源和保护环境的生态意识和生态行为。因此,提出重新设计从受教者角度出发、以产生生态行为为根本目的的生态文明教育系统,是实现生态文明教育目标的有效途径。  相似文献   
2.
The denitrifying woodchip bioreactor is designed to remediate nitrate-rich water, including those produced from aquaculture effluents. Reuse of treated bioreactor outflows in recirculating aquaculture would offer considerable water savings and valuable alkalinity recuperation. However, such bioreactors may leach detrimental wood-bound contaminants, preventing outflow reuse. To determine water reuse potential, woodchip media from two hardwood species (white ash, Fraxinus americana; Norway maple, Acer platanoides) were evaluated for 206 d under a range of operating conditions (start-up, steady-state, reducing conditions, and drying-rewetting cycles) for a spectrum of potentially harmful dissolved contaminants. Aerated outflows also were evaluated for acute and chronic toxicity to the biologically sensitive invertebrate Ceriodaphnia dubia. Dissolved metal leaching subsided within the first few weeks of operation, though initial concentrations of copper and zinc were detected at concentrations of concern. Elevated concentrations of tannins-lignin and total ammonia nitrogen were detected throughout the study and were influenced by operational phase. Acute toxicity was not generally detected, though chronic toxicity was observed during drying-rewetting cycles in the maple outflows. The measured toxicity was not correlated with water chemistry, indicating an additive effect of several toxicants. Overall, significant differences in outflow water quality between ash and maple wood species were negligible. Results indicated that bioreactor outflows may be applicable for aquacultural reuse, though reusing outflows immediately following start-up or restarting after a dry period would not be recommended.  相似文献   
3.
Small‐scale fisheries are recognised as making important contributions to nutrition and economic development despite a lack of accurate quantitative information on catches and consumption. While direct measurement remains the most appropriate way of collecting such data, it is impractical at large scales. Instead, household surveys based upon informant recall of fish caught and/or consumed are frequently used. However, the accuracy of weight recall by informants (even over short recall periods) has not been established. Using data from household surveys, the accuracy and precision of catch and consumption estimates derived from: (a) asking informants to recall weights of fish caught and (b) asking respondents to recall lengths of fish caught and converting to weight were tested. Length‐based methods, using visual aids to assist recall, were more accurate, precise and correctable. These methods could be useful for catch estimation, especially where fish are processed, sold or consumed shortly after capture.  相似文献   
4.
The aim of this research was to determine the effect of three different fertilizing systems, including organic, conventional, and integrated ones, on the yield, fruit quality, antioxidant activity, and some phenolic compounds of white seedless grape. The study was carried out on several 6-year-old white seedless grapevine located in the Urmia Province (North-West Iran). The results showed that the fruit physical characteristics and yield were affected significantly by different fertilization systems. The highest yield was observed in the conventional fertilization, followed by organic and integrated systems. The leaf mineral contents were obviously dependent on the different fertilization used, whereas pH and titratable acidity were not affected. Based on our results, the highest values of antioxidant activity and total flavonoid were found in the organic and integrated fertilization systems, respectively. Also, the highest contents of total phenolic, catechin, and quercetin-3-galactoside were observed in the organic fertilization system. Overall, the highest nutritional quality and biochemical characteristics of white seedless grape were obtained in organic fertilization system, which improved antioxidant capacity by enhancing total phenolics, total flavonoids and valuable phenolic compounds.  相似文献   
5.
基于陕西省西安市鄠邑区葡萄种植户的调查数据,在构建农户层面效益评价指标体系的基础上,评价了农户种植葡萄的效益状况。结果表明:第一,农户葡萄种植效益整体位于中等偏下的水平;第二,高效益农户与低效益农户在经济效益、生态效益以及就业机会上存在显著差异,而在对子女和老人的照顾上差异不大;第三,经验丰富、种植规模较大的纯农业型农户的效益较高。节水灌溉技术有助于提高农户的经济效益,而购买化肥的渠道、接受技术培训和有购买过假化肥经历对农户种植经济林的生态效益有影响。  相似文献   
6.
为了探索福建省茎用芥菜1年2代繁育技术,选择6个茎用芥菜品种,分别进行冬春季正常繁育和夏秋季高山加代繁育的2代繁育试验,并对比各品种2代繁育的生育期、株高、株幅和种子产量。结果表明:所有参试茎用芥菜品种只要通过打破种子休眠、衔接好2代繁育的播种期都能完成1周年2代繁育,夏秋季高山加代繁育的全生育期比冬春季正常繁育平均缩短约50 d;冬春季繁育比夏秋季高山加代繁育株高增加31.2%~132.9%,株幅增加1.5%~21.8%,所有参试品种冬春季繁育的种子产量都极显著高于相应夏秋季高山加代繁育,种子产量增加17.8%~153.6%。  相似文献   
7.
夫妻双方的年龄、受教育程度、收入以及户籍方面的差异会影响婚后的主观幸福感。夫妻双方的年龄差距越大,生活幸福感越弱,且这种影响更多地存在于男性和农业户籍人口中;夫妻双方的受教育程度差距虽然有利于女性主观幸福感的提升,却会恶化男性的主观幸福感;夫妻双方的收入差距越大,生活幸福感越强,且对于女性和农业户籍人口而言,收入差距对生活幸福感的影响更为显著;与夫妻双方都是农业户籍相比,夫妻双方都是非农业户籍的幸福感更强。夫妻双方的个人特征差异对婚后主观幸福感的影响存在性别与户籍差异。  相似文献   
8.
This observational study aimed to determine MRSA prevalence using strain‐specific real‐time PCR at the pig level, stratified by age groupings, within a pig enterprise. A total of 658 samples were collected from individual pigs (n = 618) and the piggery environment (n = 40), distributed amongst five different pig age groups. Presumptive MRSA isolates were confirmed by the presence of mecA, and MALDI‐TOF was performed for species verification. All isolates were tested against 18 different antimicrobials. MRSA was isolated from 75.2% (95% CI 71.8–78.6) of samples collected from pigs, and 71% of the MRSA isolates from this source were identified as community‐associated (CA)‐MRSA ST93, while the remainder were livestock‐associated (LA)‐MRSA ST398. Amongst environmental isolates, 80% (CI 64.3–95.7) were ST93 and the remainder ST398. All MRSA isolates from pigs and the environment were susceptible to ciprofloxacin, gentamicin, linezolid, mupirocin, rifampicin, sulfamethoxazole–trimethoprim, teicoplanin and vancomycin. Phenotypic rates of resistance were penicillin (100%), clindamycin (97.6%), erythromycin (96.3%), ceftiofur (93.7%), chloramphenicol (81.2%), tetracycline (63.1%) and amoxicillin–clavulanate (63.9%). A low prevalence of resistance (9.2%) was observed against neomycin and quinupristin–dalfopristin. The probability of MRSA carriage in dry sows (42.2%) was found to be significantly lower (p < .001) when compared to other age groups: farrowing sows (76.8%, RR1.82), weaners (97.8%, RR 2.32), growers (94.2%, RR 2.23) and finishers (98.3%, RR 2.33). Amongst different production age groups, a significant difference was also found in antimicrobial resistance for amoxicillin–clavulanate, neomycin, chloramphenicol and tetracycline. Using the RT‐PCR assay adopted in this study, filtering of highly prevalent ST93 and non‐ST93 isolates was performed at high throughput and low cost. In conclusion, this study found that weaner pigs presented a higher risk for CA‐MRSA and antimicrobial resistance compared to other age groups. These findings have major implications for how investigations of MRSA outbreaks should be approached under the One‐Health context.  相似文献   
9.
碳点(CDs)和石墨烯量子点(GQDs)由于结构稳定、环境友好、水分散性和生物相容性良好、易于功能化改性和可光致发光等优点已成为备受关注的零维碳纳米材料,有望广泛应用于生化指示、生物医学、储能、显示器件和催化等前沿领域。近年来,相比于传统的化石燃料基化合物,来自可再生生物质的木质素及其衍生物不仅价廉易得、活性基团丰富,而且具有天然芳香结构,已成为CDs和GQDs的重要前驱体。但是,已有报道对木质素的解聚机制认识不足,这也逐渐成为制约木质素基CDs和GQDs性能提升的瓶颈之一。因此,必须阐明木质素在相关工艺过程中发生解聚的化学本质,并明确杂原子掺杂与木质素基CDs和GQDs的激发依赖发光行为的内在联系。笔者首先介绍了木质素基CDs和GQDs的制备方法发展历程和潜在应用,同时对其结构和性质等进行评述,重点讨论并总结了制备具有出色激发依赖发光行为的木质素基CDs和GQDs的技术难点,认为开发一类适用于普遍性木质素原料的高效环保解聚策略,以及揭示木质素基CDs和GQDs的杂原子掺杂与其激发依赖发光行为的关联机理将成为该领域今后的重点研究方向。  相似文献   
10.
Vegetatively propagated crop (VPC) seed tends to remain true to varietal type but is bulky, often carries disease, and is slow to produce. So VPC seed needs to be handled differently than that of other crops, e.g., it tends to be sourced locally, often must be fresh, and it is less often sold on the market. Hence, a framework was adapted to describe and support interventions in such seed systems. The framework was used with 13 case studies to understand VPC seed systems for roots, tubers, and bananas, including differing roles and sometimes conflicting goals of stakeholders, and to identify potential coordination breakdowns when actors fail to develop a shared understanding and vision. In this article, we review those case studies. The framework is a critical tool to (a) document VPC seed systems and build evidence; (b) diagnose and treat coordination breakdown and (c) guide decision-makers and donors on the design of more sustainable seed system interventions for VPCs. The framework can be used to analyze past interventions and will be useful for planning future VPC seed programs.  相似文献   
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