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Creeping permafrost in Mexico:environmental status of“Nevado”Rock Glacier,Nevado de Toluca volcano
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作者 Víctor SOTO Kenji YOSHIKAWA +2 位作者 Rafael TORRES-OROZCO Carlos M.WELSH-RODRÍGUEZ Hugo DELGADO-GRANADOS 《Journal of Mountain Science》 2025年第9期3154-3166,共13页
In contrast to glaciological studies in Mexico,periglacial studies are very recent and limited to the analysis of the general permafrost cover in the high mountains of the country.Although some of the studies on the r... In contrast to glaciological studies in Mexico,periglacial studies are very recent and limited to the analysis of the general permafrost cover in the high mountains of the country.Although some of the studies on the reconstruction of Pleistocene glaciers in Mexico mention the existence of rock glaciers,to date no work has been done to study their physical properties or determining their state of conservation.Since rock glaciers are the most important visible indicators of mountain permafrost(along with features such as gelifluction lobes and patterned ground)and given that the“Nevado”rock glacier is the main example of its kind in Mexico,this study analyzes its internal temperature and assesses its state of conservation.The investigation was carried out by drilling and thermal monitoring of rock profiles as well as air.The results indicate that at present,the“Nevado”seems to lack permafrost inside.Although there is evidence of surface freezing during the winter months in the upper part of the rock glacier,in the lower portion it is almost unnoticed;and in both parts the internal temperature shows a tendency towards positive values as depth increases,a situation that predominates throughout the year.In addition,according to the records of the climatological station located in the lower part of the rock glacier,although the annual rainfall regime could be favorable for the formation and feeding of interstitial or segregated ice,the air temperature conditions throughout the year prevent permanent freezing.The sum of the above determines that at present the“Nevado”could be considered as an inactive and relict-type rock glacier;the presence of vegetation on the surface of the debris that make it up corroborates its inactivity. 展开更多
关键词 Ice-rich permafrost Rock glacier Nevado de Toluca creeping permafrost Glaciogenic rock glacier Periglacial environment
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Biosynthesized CoS by Shewanella algae for efficient organic pollutants degradation via peroxymonosulfate activation:Augmented catalytic activity and minimized environmental toxicity
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作者 Jing Yang Xiaofan Zhai +5 位作者 Shiqi Zhang Peng Ju Zihao Li Chenlu Wang Jizhou Duan Baorong Hou 《Journal of Materials Science & Technology》 2025年第32期197-208,共12页
Cobalt-based catalysts were regarded as highly effective for pollutant degradation through peroxymono-sulfate activation.Nevertheless,conventional synthesis methods for cobalt-based catalysts were associ-ated with iss... Cobalt-based catalysts were regarded as highly effective for pollutant degradation through peroxymono-sulfate activation.Nevertheless,conventional synthesis methods for cobalt-based catalysts were associ-ated with issues of cobalt ion leakage,which posed a risk of secondary environmental contamination.Addressing this issue,a novel cobalt-based catalyst,CoS nanoparticles,was biosynthesized by Shewanella algae and designated as SA@CoS.SA@CoS,a nanoflower coated with proteins/peptides,contained a sig-nificant number of sulfur vacancies.Compared to chemically synthesized CoS,SA@CoS exhibited lower cobalt ion release(0.13 mg/L)and higher catalytic activity.Based on this,SA@CoS was employed to de-grade Rhodamine B(RhB)and tetracycline(TC)by activating peroxymonosulfate.The results indicated that the degradation efficiencies of RhB and TC could reach 99.9%and 90.5%within 10 min,respec-tively.Further analyses revealed that both radical(·O_(2)^(-),·OH and SO_(4)^(·-))and non-radical(_(1)O_(2))pathways were involved in the degradation of RhB and TC,with the non-radical pathway dominating the degra-dation process.This work not only offered a facile approach for the biosynthesis of stable cobalt-based catalysts,but also underscored the immense potential of biogenic nano-catalysts in the realm of environ-mental remediation. 展开更多
关键词 Biosynthesis Cobalt-based catalyst Rhodamine B TETRACYCLINE Peroxymonosulfate activation
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税收调节作用下生态工业园区共生关系网络演化机理
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作者 许玲燕 王振宇 杜建国 《系统工程》 北大核心 2026年第1期19-34,共16页
当前我国生态工业园区在其生态产业链可持续发展进程中,仍存在着工业共生关系网络建设内生动力不足、质量及稳定性差等问题。而税收调节机制作为财富分配和社会公平的重要手段,在引导企业优化资源利用方式、促进生态工业园区上下游企业... 当前我国生态工业园区在其生态产业链可持续发展进程中,仍存在着工业共生关系网络建设内生动力不足、质量及稳定性差等问题。而税收调节机制作为财富分配和社会公平的重要手段,在引导企业优化资源利用方式、促进生态工业园区上下游企业间资源共享与循环利用、利益再分配等方面发挥着关键作用。因此,研究基于生态工业园区企业间工业共生关系的双层网络特征和博弈关系,构建了由上游废弃物供应商群体、下游制造商群体构成的工业共生网络演化博弈模型,研究了市场供需作用与环境税、退税补贴等税收调节作用下的工业共生关系网络扩散过程,并通过案例分析和数值模拟深入研究相关因素的影响作用。研究表明:相较于市场供需机制,税收机制调节并促进了工业共生关系网络扩散与稳定;共生额外成本、工业废弃物交易价格与自主处理成本的上涨,有助于推动上游废弃物供应商群体参与工业共生关系,实现资源的充分利用;下游制造商群体的共生意愿,易受原材料采购价格变化的影响;共生额外成本的均摊机制,可有效激励上下游企业群体更积极地参与工业共生关系;环境税有助于推动上游废弃物供应商群体加入共生网络,增加退税补贴促进了上下游群体的共生意愿,且对上游废弃物供应商的影响更为显著。 展开更多
关键词 税收调节 生态工业园区 工业共生关系 复杂网络演化博弈
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某特种装备发射车湿热海洋大气自然环境试验及改进对策
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作者 胥泽奇 周彩元 +1 位作者 李正雄 张世艳 《装备环境工程》 2026年第1期145-153,共9页
目的 通过自然环境试验考核特种装备发射车湿热海洋大气环境适应性,筛选最优设计方案,识别潜在设计缺陷及薄弱环节,并提出环境适应性改进对策。方法 依据产品结构层次,系统选取试片、标准件、元器件、试件、部组件与整机等多层级试验样... 目的 通过自然环境试验考核特种装备发射车湿热海洋大气环境适应性,筛选最优设计方案,识别潜在设计缺陷及薄弱环节,并提出环境适应性改进对策。方法 依据产品结构层次,系统选取试片、标准件、元器件、试件、部组件与整机等多层级试验样品,采用户外、棚下、库内暴露/贮存等自然环境试验方式,模拟车辆上的舱外完全暴露、底盘底部、车上遮蔽通风/挡风、舱(箱)内裸露/封闭等典型局部条件。基于试验结果,结合试验目的进行分析,提出针对性改进对策。结果 通过1 a的自然环境试验,实现了对材料、防护工艺和元器件环境适应性的有效评估,优选出适应性良好的设计,并暴露了试件、部组件与整机的缝隙腐蚀、电偶腐蚀等典型问题。利用以2~4 a的延续试验数据,进一步验证试验结果,并为环境适应性设计积累了系统的基础数据。结论 多层级样品试验可全面考核材料、防护工艺及器件在复杂环境下的适应性,显著提升试验效率。多种自然环境试验方式的组合应用,能够更真实地模拟发射车实际环境条件,从而提高试验结果的准确性与工程适用性,为装备环境适应性设计与改进提供可靠依据。 展开更多
关键词 发射车 湿热海洋大气环境 自然环境试验 环境适应性改进 筛选试验 验证试验 薄弱环节
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Curtain Wall Systems as Climate-Adaptive Energy Infrastructures:A Critical Review of Their Role in Sustainable Building Performance
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作者 Samira Rastbod Mehdi Jahangiri +1 位作者 Behrang Moradi Haleh Nazari 《Energy Engineering》 2026年第1期27-55,共29页
Curtain wall systems have evolved from aesthetic facade elements into multifunctional building envelopes that actively contribute to energy efficiency and climate responsiveness.This reviewpresents a comprehensive exa... Curtain wall systems have evolved from aesthetic facade elements into multifunctional building envelopes that actively contribute to energy efficiency and climate responsiveness.This reviewpresents a comprehensive examination of curtain walls from an energy-engineering perspective,highlighting their structural typologies(Stick and Unitized),material configurations,and integration with smart technologies such as electrochromic glazing,parametric design algorithms,and Building Management Systems(BMS).Thestudy explores the thermal,acoustic,and solar performance of curtain walls across various climatic zones,supported by comparative analyses and iconic case studies including Apple Park,Burj Khalifa,and Milad Tower.Key challenges—including installation complexity,high maintenance costs,and climate sensitivity—are critically assessed alongside proposed solutions.A central innovation of this work lies in framing curtain walls not only as passive architectural elements but as dynamic interfaces that modulate energy flows,reduce HVAC loads,and enhance occupant comfort.The reviewed data indicate that optimized curtain wall configurations—especially those integrating electrochromic glazing and BIPV modules—can achieve annual energy consumption reductions ranging fromapproximately 5%to 27%,depending on climate,control strategy,and facade typology.The findings offer a valuable reference for architects,energy engineers,and decision-makers seeking to integrate high-performance facades into future-ready building designs. 展开更多
关键词 Curtain wall systems energy efficiency climate-responsive design smart facades electrochromic glass parametric architecture building envelope technologies
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基于多生命周期的退役变压器再生利用的资源环境效益研究
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作者 王又丹 高萌 +3 位作者 卓然 吕彬 丁宁 潘浩 《中国环境科学》 北大核心 2026年第4期2337-2345,共9页
基于产品与材料多生命周期思想,应用考虑国内资源再生利用水平的核算方法,核算了典型的退役变压器中铜、钢铁和绝缘油的再生利用的资源环境效益.结果显示,以典型配电变压器为例,相对于以原生材料为基准情景的传统方法,本研究所核算减排... 基于产品与材料多生命周期思想,应用考虑国内资源再生利用水平的核算方法,核算了典型的退役变压器中铜、钢铁和绝缘油的再生利用的资源环境效益.结果显示,以典型配电变压器为例,相对于以原生材料为基准情景的传统方法,本研究所核算减排效益降低了8.74%至17.29%.同时与原生材料与再生材料分配系数0/100的截断方法、50/50的均分方法以及循环足迹模型(CFF)相比较,资源环境影响的降低比例显著高于均分方法和循环足迹模型方法,略低于截断方法.本文使用的核算方法有效利用了社会再生资源供给水平等一系列相对客观的动态化和材料特征化参数,避免了相对主观的静态参数及情景设定,可为系统准确核算变压器的再生利用的协同效益提供科学方法与数据支撑. 展开更多
关键词 资源再生 资源环境效益 温室气体 退役变压器 多生命周期
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中国草畜平衡制度的结构优化与体系完善
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作者 陈宝山 姜贺天 +1 位作者 麻芦苇 丁梦茹 《自然资源学报》 北大核心 2026年第1期71-86,共16页
草畜平衡制度在抑制牧民超载放牧、保护草原生态平衡方面发挥着重要作用,但部分地区草畜矛盾、草地退化等问题依旧严峻。运用结构功能分析法对中国草畜平衡制度进行分析发现,草畜平衡制度的实施呈现出草原保护成效较为显著,通过法律手... 草畜平衡制度在抑制牧民超载放牧、保护草原生态平衡方面发挥着重要作用,但部分地区草畜矛盾、草地退化等问题依旧严峻。运用结构功能分析法对中国草畜平衡制度进行分析发现,草畜平衡制度的实施呈现出草原保护成效较为显著,通过法律手段明确制度运行的职、权、责关系的正功能,但也产生了限制放牧行为、抑制牧户权利、最终成为一种限权行为,以及影响牧户放牧收入、降低牧户守约积极性、产生负向激励的负功能。因果检视表明,草畜平衡规范结构断裂与制度结构配置不合理的外部结构障碍,核定周期过长、约束与激励失衡和监督监测制度局限的内部结构障碍,以及奖补混同抑制牧民积极性的内外部结构衔接障碍,共同制约了制度功能的发挥。鉴于此,应统筹草畜平衡与禁牧、休牧、轮牧、舍饲等制度,完善草畜平衡法规和制度体系,优化激励约束平衡、载畜量核定和监督监测制度,构建草畜平衡补奖与草原生态产品价值实现的衔接制度,破解制度结构障碍。 展开更多
关键词 草畜平衡制度 结构功能分析 奖补衔接 生态产品价值实现
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Unveiling the origins of Northern Thailand’s haze:comprehensive chemical characterization and source apportionment of PM_(2.5) using targeted molecular markers
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作者 Supattarachai Saksakulkrai Somporn Chantara +2 位作者 Pavidarin Kraisitnitikul Deepchandra Srivastava Zongbo Shi 《Journal of Environmental Sciences》 2026年第1期635-648,共14页
Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tra... Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia. 展开更多
关键词 Chiang Mai Smoke haze Biomass burning PM_(2.5) Source apportionment Positive matric factorization
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叶绿素荧光技术在浮游植物生理生态研究中的应用
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作者 徐魁 陈珍 +4 位作者 李伟智 陶佳奇 罗唯欣 邬珣 陈雄文 《水生态学杂志》 北大核心 2026年第2期244-252,共9页
叶绿素荧光技术具有灵敏、简便、快捷、包含信息丰富和无损伤等优点,在浮游植物生理生态研究中应用广泛。本文对叶绿素荧光参数的测定和分析等常见问题做了综合介绍,总结了脉冲调制式荧光技术与单闪光和多闪光荧光技术的原理和特点,及... 叶绿素荧光技术具有灵敏、简便、快捷、包含信息丰富和无损伤等优点,在浮游植物生理生态研究中应用广泛。本文对叶绿素荧光参数的测定和分析等常见问题做了综合介绍,总结了脉冲调制式荧光技术与单闪光和多闪光荧光技术的原理和特点,及其常见荧光参数如光系统Ⅱ(PSⅡ)最大光合效率(ΦM)、电子传递速率(ETR)、非光化学淬灭(NPQ)的测定方法,随后分析了上述常见荧光参数变化的生理生态意义。此外,还介绍了叶绿素荧光技术与其他光合作用测定技术在浮游植物生理生态研究中的联用。最后,介绍了近几年浮游植物生理生态研究中叶绿素荧光技术的最新应用,并展望了未来叶绿素荧光技术的应用发展方向。 展开更多
关键词 叶绿素荧光技术 浮游植物 非光化学淬灭 初级生产力
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Reducing environmental risk of nitrogen by popularizing mechanically dense transplanting for rice production in China 被引量:7
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作者 HUANG Min ZOU Ying-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2362-2366,共5页
The high nitrogen(N)application rates typically used in Chinese cropping systems have led to diminishing returns for yields and have also imposed substantial environmental costs.Here,we estimate that the annual N loss... The high nitrogen(N)application rates typically used in Chinese cropping systems have led to diminishing returns for yields and have also imposed substantial environmental costs.Here,we estimate that the annual N loss from rice production in China reached approximately 2.6×109 kg from 2011 to 2015,and we demonstrate that adoption of the mechanically dense transplanting technique by producers is an effective method to reduce N loss from rice cropping systems without suffering a yield penalty. 展开更多
关键词 dense planting environmental risk mechanical transplanting nitrogen loss RICE
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Alternatives of Strategic Environmental Assessment for Road Traffic Development Planning——Case of Changchun City,China 被引量:4
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作者 CHEN Chong XU Yex +1 位作者 SHANG Jincheng Gordon HUANG 《Chinese Geographical Science》 SCIE CSCD 2009年第1期25-36,共12页
On analyzing the achievement of the goal in the modem urban road traffic development planning, the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme, the exte... On analyzing the achievement of the goal in the modem urban road traffic development planning, the alternative of Strategic Environmental Assessment for urban traffic planning should include the basic scheme, the extended scheme and the environmental protection scheme. This study from different perspectives designed the alternatives for Changchun's county-level road and urban road system planning, and used the method of System Dynamics to simulate, optimize and analyze those alternatives. Thereafter, some methods including the correlation function method were used to comprehensively assess and rank those alternatives for recommending two best alternatives with the consideration to the indicators, such as the total emission amount of CO, the total emission amount of nitrogen oxides, the noise value, the road construction cost, the fossil oil consumption and the traffic capacity. The result showed that the study would provide substantial supports for decision-makers to make more scientific decisions and promote the sustainable urban traffic in Changchun City. 展开更多
关键词 road traffic traffic planning Strategic Environmental Assessment (SEA) correlation function Changchun City
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Water quantity-quality combined evaluation method for rivers' water requirements of the instream environment in dualistic water cycle: A case study of Liaohe River Basin 被引量:2
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作者 WANG Xiqin ZHANG Yuan LIU Changming 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期304-316,共13页
In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relatio... In this article the meaning of the quantity and quality of environmental flows of river in dualistic water cycle is discussed, and compared with the meaning of unitary water cycle. Based on the analysis of the relationship between environmental flows of river requirements, the efficiency of water resource usage, the consumption coefficient, and the concentration of waste water elimination, the water quantity and water quality calculation method of the environmental flows of river requirements in dualistic water cycle is developed, and the criteria for environmental flows of river requirements are established, and therefore the water quantity-quality combined evaluation of natural river flows requirements are realized Taking the Liaohe River as a model, the environmental flows of river requirements for Xiliao River, Dongliao River, mainstream Liaohe River, Huntai River and northeast rivers along the coasts of the Yellow and Bohai seas in unitary water cycle are calculated, each taking up 39.3%, 63.0%, 43.9%, 43.3% and 43.5% of runoff respectively. Evaluated according to Tennant recommended flow, the results show that: except Xiliao River is "median", the rest are all upon "good", the Dongliao River is even "very good". The corresponding results in dualistic water cycle are that, the proportion of natural flows for each river is 57.5%, 74.1%, 60.8%, 60.3% and 60.4%; while the combined evaluation results show that: considering "quantity", except Xiliao River, the rest rivers can all achieve the "quantity" criteria of the en- vironmental flows of river requirements, but if considering the aspect of "quality", only Dongliao River can reach the "quality" standard. By water quantity-quality combined evaluation method, only Dongliao River can achieve the criteria. So the water quality is the main factor that determines whether the environmental flows can meet the river ecosystem demands. 展开更多
关键词 dualistic water cycle RIVERS environmental flows of river requirements water quantity water quality evaluation Liaohe River
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The characteristics of vascular endothelial injuries induced by extreme environmental factors 被引量:1
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作者 Wei LIU Jia-ying LIU +2 位作者 Zhao-yun YIN Chao-liang LONG Hai WANG 《中国应用生理学杂志》 CAS CSCD 2013年第6期494-500,共7页
Vascular endothelium plays an important role in regulating vascular homeostasis. Over the past years, it has become clear that endothelial dysfunction is a key event of pathophysiological changes in the initiation and... Vascular endothelium plays an important role in regulating vascular homeostasis. Over the past years, it has become clear that endothelial dysfunction is a key event of pathophysiological changes in the initiation and progression of injuries induced by extreme environmental factors. The present review summarizes current understanding of vascular endothelial dysfunction induced by hypoxia, cold and heat, and provides the information for prevention and treatment of environmental exposure injuries. 展开更多
关键词 血管内皮细胞 环境因素 损伤 诱发 功能障碍 生理变化 环境风险 缺氧
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Research Progress of Brackish Water Desalination by Reverse Osmosis 被引量:1
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作者 Pan Zhang Jingtao Hu +1 位作者 Wei Li Houbo Qi 《Journal of Water Resource and Protection》 2013年第3期304-309,共6页
Brackish water (BW) desalination is a primary path to relieve the shortage of water. As one of the BW desalination methods, reverse osmosis (RO) technology has advantage for both technology and process procedure. The ... Brackish water (BW) desalination is a primary path to relieve the shortage of water. As one of the BW desalination methods, reverse osmosis (RO) technology has advantage for both technology and process procedure. The expounding of this research studied or reviewed recent years, reverse osmosis membrane, energy recovery, new energy and application technology in BW desalination of RO at home and abroad. Wind power and solar energy can be combined with energy recovery device for RO. The research also explains that BW desalination by RO is practical and feasible in some areas in China. 展开更多
关键词 BRACKISH WATER REVERSE Osmosis DESALINATION NEW ENERGY
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不同格网尺度下城市形态对北京四环内地表温度的季节性影响
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作者 多玲花 段雅卿 王俊淇 《应用生态学报》 北大核心 2026年第3期683-694,共12页
随着城市化进程的不断深入,城市形态的改变对地表温度变化产生重要影响。尽管城市形态对热环境的影响已引起关注,但在多尺度格网分析和季节性对比方面仍存在探索空间。本研究以北京四环内为研究区,利用随机森林模型计算各城市形态因子... 随着城市化进程的不断深入,城市形态的改变对地表温度变化产生重要影响。尽管城市形态对热环境的影响已引起关注,但在多尺度格网分析和季节性对比方面仍存在探索空间。本研究以北京四环内为研究区,利用随机森林模型计算各城市形态因子对地表温度的相对重要性,探究不同格网尺度下各城市形态因子对地表温度的季节性影响,通过双变量空间自相关分析城市形态因子与地表温度空间分布的相关性。结果表明:在180~360 m格网尺度范围内,各城市形态因子与地表温度的拟合度整体均随格网尺度增加呈现先增加后降低的变化趋势,其中,300 m格网尺度的模型拟合度最优,可用该尺度对城市进行规划,以缓解城市热岛效应。城市形态对地表温度的影响具有显著季节性差异,春季,建筑高度对地表温度的影响最大,相对重要性值为3.36;夏季和秋季,建筑用地的密集程度对地表温度的影响达到峰值,相对重要性值分别为4.21和4.39;冬季,城市植被覆盖状况对地表温度的影响显著,相对重要性值为2.15。各城市形态因子中,归一化建筑指数与地表温度呈正相关,归一化植被指数、建筑高度、建筑体积、天空开阔度与地表温度呈负相关,各城市形态因子与地表温度均呈现一定的局部空间相关性。本研究以城市形态为切入点,拓展了对地表温度多尺度、季节性变化规律的认知,揭示了其空间异质性特征,可为气候适应型城市规划及热环境差异化调控策略的制定提供科学支撑。 展开更多
关键词 城市形态 地表温度 尺度效应 季节变化 随机森林模型
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Comparison of sedimentary organic carbon loading in the Yap Trench and other marine environments
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作者 LI Dong ZHAO Jun +5 位作者 LIU Chenggang SUN Chengjun CHEN Jianfang PAN Jianming HAN Zhengbing HU Ji 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2020年第3期619-633,共15页
Knowledge about organic carbon loadings(ratio of sedimentary organic carbon(SOC)content to specific surface area(SSA))and the fate of organic carbon(OC)is critical to understand the marine carbon cycle.We investigated... Knowledge about organic carbon loadings(ratio of sedimentary organic carbon(SOC)content to specific surface area(SSA))and the fate of organic carbon(OC)is critical to understand the marine carbon cycle.We investigated the variations in the patterns of OC loadings and the preservation capacities of sedimentary OC in the Yap Trench and other marine environments.The average OC loading in sediment cores from various marine environments decreases with increasing water depth at a rate of^0.06 mg OC/(m^2·km)(R^2=0.23,P<0.01).Distinct low OC loadings(0.09±0.04 mg OC/m^2)were observed in the Yap Trench,with the lowest values as^0.02 mg OC/m^2.A further comparative analysis indicated that OC/SSA=0.2 mg OC/m^2 is a good indicator to distinguish between oxic deep-sea regions and suboxic energetic deltaic areas.Regression analysis between OC loading and bulk carbon isotope compositions indicates that marine OC(δ13C^-20.4‰to-18.6‰)dominates the lost OC within the Yap Trench and does not differ from that of the abyssal zone.In contrast,terrestrial OC withδ13C values of approximately-27.4‰to-20.5‰was the major source of remineralized OC in the sublittoral zone.The ratios of OC loadings in the bottom layer relative to those in the top layers of sediment cores indicate that the preservation capacities of hadal trenches are much lower than those of other environments,and only approximately 30%of the SOC deposited in hadal trenches is finally buried.The value is equivalent to 0.066%of the primary production-derived OC and much lower than the global ocean average(~0.3%).Overall,the hadal zone exhibits the lowest OC loading and preservation capacity of SOC of the different marine environments investigated,despite the occurrence of a notable funneling effect. 展开更多
关键词 Yap TRENCH hadal zone organic carbon LOADING specifi csurface area PRESERVATION capacity
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Integrated assessment of urban environment in China
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作者 Wang Gui-lian Lu Yong-long 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第3期272-278,共7页
The principles and procedures for integrated environmental assessment(IEA) based on the specific urban conditions and Chinese characteristics have been developed. The development processes and the general principles a... The principles and procedures for integrated environmental assessment(IEA) based on the specific urban conditions and Chinese characteristics have been developed. The development processes and the general principles and procedures are presented in this paper. Indicators and methods for IEA may vary from case to case, but guidelines for selection of indicators and methods may be applicable for a specific case, so they are also introduced. Although great progress has been made in IEA, there is still a lot for future development. Prospects are presented as follows: (1) IEA at strategic level; (2) mechanisms for public involvement; (3) post project analysis; (4) cumulative impact assessment; and (5) application of new approaches such as expert system and GIS in IEA. 展开更多
关键词 integrated assessment urban environment environmental assessment China.
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Strategic Environmental Assessment:A New Tool for Ecological Urbanization of Coastal Cities in China
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作者 Fang Qinhua Zhang Luoping +3 位作者 Hong Huasheng Chen Weiqi Jiang Yuwu Chen Bin 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第3期45-50,共6页
Recently, there has been growing concerns about environmental issues related to urbanization in China. The intense natural resources utilization and increasing population has brought great pressure, especially in coas... Recently, there has been growing concerns about environmental issues related to urbanization in China. The intense natural resources utilization and increasing population has brought great pressure, especially in coastal areas, consequently affecting the sustainable development of coastal cities. In 2002, Environmental Impact Assessment Act (EIA Act) was enacted in China. Environmental impact assessment targeted at planning, one level of strategic environmental assessment (SEA), thus became a legislative requirement. This paper considers SEA to be one of the important approaches not only to control coastal pollution, but also to conserve coastal ecosystems and finally to achieve sustainable development during urbanization, thus it will be a set an example for other areas of China. The experience of SEA in Xiamen, a coastal city in southeast China, illustrates the potentials of SEA. This paper first briefly introduces the concept and potentials of SEA, then compares two SEA cases and a project EIA case in Xiamen, and finally identifies the key characteristics of SEA. 展开更多
关键词 strategic environmental assessment environmental impact assessment PRACTICE comparison CHARACTERISTICS
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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico
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作者 Víctor SOTO Carlos M.WELSH R. +1 位作者 Kenji YOSHIKAWA Hugo DELGADO GRANADOS 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1954-1977,共24页
The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m asl.The retracti... The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m asl.The retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the mountain.There is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground temperature.The results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and proglacial.It was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty minutes.The rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the site.This activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction activity.The geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water. 展开更多
关键词 FREEZE-THAW Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios
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Does melanin-based plumage coloration reflect health status of free-living birds in urban environments?
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作者 Hani Amir Aouissi Mostefa Ababsa +3 位作者 Aissam Gaagai Zihad Bouslama Yassine Farhi Haroun Chenchouni 《Avian Research》 SCIE CSCD 2021年第4期553-568,共16页
Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physio... Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments.A trait of high importance,the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons(Columba livia)in North African urban habitats.Methods:Different body morphometrics,hematological and hemoparasitic parameters were quantified on freeliving Feral Pigeons in urban environments of northern Algeria.Moreover,plumage melanin-based coloration(MBC)was measured and the data collected at the individual scale was correlated with the previous parameters using linear and non-linear modeling approaches.Results:Plumage MBC scores of the sampled Feral Pigeons ranged between 0.3%and 74.8%.Among the 12 morphological traits measured,body weight,tail length and total length were deemed to be positively correlated with MBC.Darker morphs appeared to have more hemoparasites compared to lighter pigeons.Quite the same observation goes with the immunity but with non-linear trends.The number of monocytes and granulocytes increased with the increase in MBC levels in lighter morphs,while pigeons with high MBC scores exhibited negative relationships between MBC levels and the number of white blood cells.Conclusions:Despite the existence of a number of studies demonstrating phenotypic directional selection,further studies are undoubtedly necessary to understand in detail the underlying mechanisms in species life-history strategies between differently colored individuals.Findings of this correlative study open exciting perspectives revealing that MBC can be considered a good indicator of and health status and adaptation strategies to changes in urban environments. 展开更多
关键词 Columba livia Feather color polymorphism Feral birds Hematological indicators Hemoparasitism Immune ecophysiology Urbanization Urban ornithology
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