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1.
Sexually selected traits that act as signals of quality often display some degree of condition dependence. In birds, condition dependence of ornamental plumage is often mediated by production costs related to acquisition or allocation of dietary resources. White plumage ornaments, however, have often been assumed to be inexpensive because their production requires neither pigment nor specialized feather structure. In male dark-eyed juncos (Junco hyemalis), the size of a white patch on the tail contributes to attractiveness and mating success. Using captive males, we examined the effects of diet quality on the size and brightness of the tail-white patch. After removing four tail feathers to induce replacement, we maintained subjects on a subsistence (low-protein) or enriched (high-protein) diet while induced feathers grew. Birds that received an enriched diet grew their feathers more quickly and grew larger, brighter white patches. Feather growth rate was positively correlated with the increase in the size of the tail-white patch, a relationship that was stronger in the subsistence diet group. However, within diet treatments, faster-grown feathers were slightly duller. Taken together, these results suggest that variation in diet quality may lead to condition-dependent expression of tail white and that condition dependence may be stronger in more stressful environments. We suggest a mechanism by which increased feather growth rate may lead to an increase in the size of the tail-white patch and discuss potential trade-offs between signal size and brightness.  相似文献   
2.
铜及其与四环素的联合暴露对斑马鱼胚胎的毒性效应   总被引:1,自引:0,他引:1  
近年来工业和养殖业中铜和四环素的滥用,导致了一定程度的水环境污染问题。为探究铜与四环素对水生生物的毒害作用,选择斑马鱼作为受试生物,研究了铜及其与四环素的联合暴露对斑马鱼胚胎的毒性效应,并进一步探索了其中可能的致毒机制。结果表明:铜在低浓度下(10%致死浓度LC10=2.5μg·L~(-1),10%效应浓度EC_(10)=0.1μg·L~(-1))明显延迟了斑马鱼胚胎的孵化、卵黄囊吸收、头部、鱼鳔和体长等生长指标的发育,同时在心脏区域引起了明显的细胞凋亡效应。幼鱼体内总铜含量检测结果显示低浓度下铜的生物利用度相对更高。基因表达结果显示环境浓度的铜可能通过影响神经和心脏相关基因的表达引起斑马鱼胚胎的神经发育和心脏发育异常。铜和四环素的联合暴露实验结果表明二者的复合污染类型为拮抗作用,且两者相互作用可以形成络合物。综合以上结论,说明环境浓度的铜可能通过细胞凋亡、分子水平的变化等方式对水生生物的早期生长发育产生危害,如延迟生长发育、神经及心脏发育异常,另外铜可通过和四环素等环境中其他污染物的结合改变铜的生物有效性和毒性。  相似文献   
3.
分析了我国目前实施危险废物交易的意义和必要性及危险废物交易现状,提出在危险废物交易还处于市场化运行的初级阶段,引入信息化技术,为危险废物交易同时提供监管和市场化平台,建立健全配套的管理制度和办法,是实现危险废物的循环利用和经济可持续发展的有效途径之一。  相似文献   
4.
结合我国国情,对绿色建筑的基本概念和要达到的目标进行了分析。综合可持续发展评价体系以及我国目前在绿色建筑方面的发展进程,提出全面推进绿色建筑,完善建筑业可持续发展体系的措施建议。  相似文献   
5.
维持经济的持续稳定增长是我国的重要政策目标,然而面对日趋严峻的资源、环境制约,大力推进生态文明建设已刻不容缓。相应地,在理论方面,研究经济增长与环境污染的双向作用机制也非常必要。利用VAR模型,研究了辽宁省经济发展与环境之间的关系,发现两者之间的关系并不是EKC理论中所说的倒u型曲线,而是呈现w型、N型等更加复杂的曲线形状。实验结果也表明辽宁省环境与经济存在双向作用机制,其中,废气与废水对辽宁省经济增长影响最大。  相似文献   
6.
湿地植物在处理高负荷有机废水时会受到不同程度的氧化胁迫。本研究基于对浮萍的有机污染胁迫模拟系统,通过对浮萍脂质过氧化和抗氧化防御系统的监测与分析,研究了浮萍对有机污染胁迫的耐受能力及胁迫去除后浮萍的恢复规律。结果表明,浮萍对有机污染胁迫具有较高的耐受性,在胁迫去除后,具有一定的恢复能力。在COD小于400mg/L时,浮萍并未受到氧化胁迫;当COD达到800 mg/L时,浮萍体内ROS含量上升,细胞膜脂过氧化加剧,但抗氧化酶活性升高,抗氧化物质含量增加,浮萍可保持生长,胁迫去除后,抗氧化防御系统可恢复到对照水平;当COD过高(≥1 000mg/L),ROS急剧上升,抗氧化防御系统遭受破坏,造成不可逆伤害,胁迫去除后不能恢复正常生长。  相似文献   
7.
    
One of the pending challenges facing Education for Sustainable Development is to change students' behavior in favor of sustainability so that these are lasting and even transferable to other people. This study analyzes how various psychological factors, including motivation, attitudes, beliefs and emotions, can be channeled to enhance social and ecological awareness through education. This paper presents an innovative approach to Sustainable Development (SD) in education, focusing on Physical Education. It highlights the intersection of Psychology, education and sustainability, showing how the first two can contribute significantly to lasting changes in students' behavior. Based on this, the Intervention Model for Sustainable Development in Physical Education (PESDIM), which combines psychological theories with specific educational strategies, is presented. In this model, which can be replicated in other educational disciplines, psychological theories are based on social interaction and norms, identity construction, motivation, beliefs and individual efficacy to improve awareness of sustainable development. The paper highlights the need for a holistic and practical approach to sustainability education in general and Physical Education in particular, stresses the importance of psychology and advocates for an educational transformation that holistically integrates sustainability into teaching methods and objectives.  相似文献   
8.
    
This study comprises two essential components: a scoping review and interviews with fishermen, both aimed at understanding the Sustainable Development Goals (SDGs) and their relevance to Offshore Wind Energy (OWE) enterprises, particularly in mitigating impacts on local fisheries. Key findings from the scoping review indicate a scarcity of research explicitly dedicated to OWE enterprises' practices concerning. The review's findings emphasize the need for further research to understand the rationale behind these decisions and to explore how OWE enterprises can optimize their practices to address SDG 2. The second part of the study involves interviews with fishermen near proposed offshore wind farm sites in Taiwan. These interviews revealed that fishermen's primary concerns revolve around SDGs 2, 8, 14, and 17. However, OWE enterprises do not prioritize SDG 2, even though fishermen express concerns related to food security, proposing the adoption of marine ranching to enhance seafood supply. Moreover, SDG 17 stands out as a priority for fishermen, while OWE enterprises overlook connections with fisheries associations and fishermen. In conclusion, this study highlights the complexity of the SDG-related issues surrounding OWE enterprises and their impact on local fisheries.  相似文献   
9.
    
Digital technology, including advancements in artificial intelligence, the Internet of Things, and data analytics, has the potential to revolutionize tackling the problem of carbon dioxide emissions and achieving sustainable development. The paper aims at checking the nature of the impact of digital technology development on carbon dioxide reduction for the EU countries in 2013–2020. The study applies the following methods: entropy methods, panel-corrected standard error, and feasible generalized least squares. The digital technology development index enabled the classification of all the EU countries into two distinct groups: High Digital Technology Development and Moderate/Lower Digital Technology Development. The findings confirm that digital technology development has a significant impact on decreasing carbon dioxide emissions. In the first stage, the growth of digital technology causes a faster decrease in carbon dioxide emissions. However, beyond a certain threshold, the further improvement of digital technology results in diminishing marginal benefits of CO2 emissions reduction. Thus, the EU government should catalyze the extension of digital technologies among all sectors and levels. In addition, it requires enhancing digital literacy of the society and local authorities.  相似文献   
10.
    
The transport sector due to growing population significantly contributes to greenhouse gases, and its share in carbon dioxide (CO2) emissions are increasing around the world. Therefore, this study investigates the linkage between research and development (R&D), transport, real income, and transport's CO2 in Organization for Economic Cooperation and Development (OECD) countries from 1990 to 2015. The study uses long‐run robust panel estimation methods such as mean group, fully modified ordinary least square, and DK standard regression that allow for heterogeneity and cross‐sectional dependence in the panel data analysis. The study finds that real income and population density contributes to CO2 emissions. Furthermore, transport infrastructure has an insignificant impact on CO2 emissions. However, R&D has a diminishing negative impact that lowers CO2 emissions. The control over the high population density and investment in R&D in clean energy production projects are necessary to combat the high rate of transport's CO2 emissions in OECD countries.  相似文献   
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