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391.
湖北丹江口库区湿地自然保护区是\"内陆湿地和水域生态系统类型\"自然保护区,但受人为活动的影响,水文情势改变,保护区的湿地生态系统受到一定的威胁。基于丹江口库区湿地自然保护区现状,从合理调整保护区范围、全面加强湿地生态建设、加强环境污染防治、建立有效的湿地保护管理协调机制、加强湿地保护知识的宣传等方面,构建和谐生态,实现人与自然协调发展。 相似文献
392.
总结了涪陵页岩气田开发初期钻井岩屑采用固化填埋方式处置存在占地面积大且易产生二次污染隐患等问题,因地制宜地探索钻井岩屑的资源化利用。分析了水基岩屑随钻预处理和油基岩屑热脱附技术,结合钻井岩屑的理化性质,开展了水基岩屑脱水后干渣制路基材料、制砖及水泥窑协同处置,油基岩屑灰渣制混凝土、制砖及水泥窑协同处置的探索和实践,基于环境安全、技术稳定可靠、消纳量大的原则,最终形成了涪陵页岩气田钻井岩屑资源化方案:水基岩屑\"随钻预处理、水泥窑协同处置\",油基岩屑\"热脱附、水泥窑协同处置\",实现了钻井岩屑的资源化综合利用。 相似文献
393.
新农村建设中水生态环境的研究——以抚宁县为例 总被引:1,自引:0,他引:1
张华帅 《中国环境管理干部学院学报》2014,(2):34-36
我国新农村建设正如火如荼地开展,但在新农村建设过程中依然存在\"脏、乱、差\"的现象。通过对秦皇岛市抚宁县农村开展调研,发现在平原、海岸滩涂区域存在过度使用化肥、农药,农村水利基本建设步伐缓慢,多数村庄没有实行垃圾定点堆放和处理机制,污染河水、海水等现象;在丘陵、山地区域存在村容村貌非常凌乱,生活垃圾远远超出了大自然的自净能力,水土流失严重等问题。抚宁县在新农村建设中应采取发展循环经济,加强山区的生态保护,分片合理开发水利管网,推广节水农业等措施。 相似文献
394.
Xing Xu Tao Zhang Shaohua Wang Zhiguang Zhou 《International Journal of Green Energy》2020,17(5):319-331
ABSTRACTEnergy management strategy (EMS) is crucial in improving the fuel economy of plug-in hybrid electric vehicle (PHEV). Existing studies on EMS mostly manage powertrain and cooling system separately which cannot get the minimum total energy consumption. This paper aims to propose a novel EMS for a new type of dual-motor planetary-coupled PHEV, which considers cooling power demand and effect of temperature on fuel economy. Temperature-modified engine model, lithium-ion battery model, two motors, and cooling system models are established. Firstly, the separated EMS (S-EMS) is designed which manages powertrain and cooling system separately. Sequentially, after the analysis of thermal characteristics of the powertrain and cooling system, the thermal-based EMS (T-EMS) is then proposed to manage two systems coordinately. In T-EMS, cooling power demand and the charging/discharging energy of motors are calculated as equivalent fuel consumption and integrated into the object function. Besides, a fuzzy controller is also established to deicide the fuel-electricity equivalent factor with consideration of the effect of temperature and state of charge on powertrain efficiency. Finally, the hardware-in-loop experiment is carried out to validate the real-time effect of EMS under the New European Driving Cycle. The result shows that cooling power demand and temperature can significantly affect the fuel economy of the vehicle. T-EMS shows better performance in fuel economy than S-EMS. The equivalent fuel consumption of the cooling system of T-EMS decreases by 27% compared with that of S-EMS. The total equivalent fuel consumption over the entire trip of PHEV using T-EMS is reduced by 9.7%. 相似文献
395.
396.
Fabrice Requier Yoan Paillet Fabien Laroche Benjamin Rutschmann Jie Zhang Fabio Lombardi Miroslav Svoboda Ingolf Steffan-Dewenter 《Conservation Letters》2020,13(2):e12693
Recent studies reveal the use of tree cavities by wild honeybee colonies in European forests. This highlights the conservation potential of forests for a highly threatened component of the native entomofauna in Europe, but currently no estimate of potential wild honeybee population sizes exists. Here, we analyzed the tree cavity densities of 106 forest areas across Europe and inferred an expected population size of wild honeybees. Both forest and management types affected the density of tree cavities. Accordingly, we estimated that more than 80,000 wild honeybee colonies could be sustained in European forests. As expected, potential conservation hotspots were identified in unmanaged forests, and, surprisingly, also in other large forest areas across Europe. Our results contribute to the EU policy strategy to halt pollinator declines and reveal the potential of forest areas for the conservation of so far neglected wild honeybee populations in Europe. 相似文献
397.
固定源烟气对比监测是保证自动监测数据质量的重要手段。但是,有效性审核比对监测过程中存在烟气排放连续监测系统安装不规范、手工监测抗干扰能力较差、烟气预处理效果不稳定及监测点位差异影响监测结果比对等问题。在此基础上,提出了严格规范环境监测点位的布置,针对不同的污染源确定适合的监测技术方法,研发完善的烟气预处理设施以及建立健全的自动监测质量保证体系等解决问题的对策。 相似文献
398.
Surface runoff losses of copper and zinc in sandy soils 总被引:1,自引:0,他引:1
Increased anthropogenic inputs of Cu and Zn in soils have caused considerable concern relative to their effect on water contamination. Copper and Zn contents in surface soil directly influence the movement of Cu and Zn. However, minimal information is available on runoff losses of Cu and Zn in agricultural soils, and soil-extractable Cu and Zn in relation to runoff water quality. Field experiments were conducted in 2001 to study dissolved Cu and Zn losses in runoff in Florida sandy soils under commercial citrus and vegetable production and the relationship between soil-extractable Cu and Zn forms and dissolved Cu and Zn concentrations in runoff water. Five extraction methods were compared for extracting soil available Cu and Zn. Concentrations of dissolved Cu and Zn in runoff were measured and runoff discharge was monitored. Mean dissolved Cu in field runoff water was significantly correlated with the extractable Cu obtained only by 0.01 mol L(-1) CaCl2, Mehlich 1, or DTPA-TEA methods. Dissolved Zn in runoff water was only significantly correlated with extractable Zn by 0.01 mol L(-1) CaCl2. The highest correlations to dissolved Cu in runoff were obtained when soil-available Cu was extracted by 0.01 mol L(-1) CaCl2. The results indicate that 0.01 mol L(-1) CaCl2-extractable Cu and Zn are the best soil indexes for predicting readily released Cu and Zn in the sandy soils. Both runoff discharge and 0.01 mol L(-1) CaCl2-extractable Cu and Zn levels had significant influences on Cu and Zn loads in surface runoff. 相似文献
399.
张卉 《中国环境管理干部学院学报》2008,18(2):32-34
本文叙述了生态城市理念的由来,生态城市的特征以及建设生态城市的意义,在分析我国生态示范区建设现状的基础上,提出生态城市建设的措施:以科学发展观为指导,以可持续发展为主题,以城市规划为蓝本,以环境保护为重点,通过调整产业结构、建立循环经济体系,发展生态农业,建设经济、社会、生态高度和谐的生态城市. 相似文献
400.
为研究城区近地面CH_4浓度特征,于2015年在潍坊市开展了CH_4连续观测实验,分析了地面风向、风速对CH_4浓度的影响。结果表明,2015年潍坊城区CH_4浓度均值为1.411 mg/m~3,季节变化特征表现为冬季高、夏季低,月均浓度分布在0.872~1.788 mg/m~3之间;日变化呈现出单峰型形态,凌晨高、下午低;偏西和偏南风向上,地面风速越大,CH_4浓度越高,在偏东风向上,CH_4浓度随风速增大而减小。 相似文献