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121.
122.
我国城市规划中气候信息应用回顾与展望 总被引:1,自引:1,他引:1
城市规划中气候信息的应用经历了从早期的风玫瑰图利用到考虑风、温、湿、压等要素的气候适宜性分析以及目前关注城市通风环境、热环境以及污染敏感区的城市环境气候图技术的历程。气候信息获得的途径也从数量极为有限的基本气象观测站资料到空间加密的自动气象站资料、更精细的气象数值模式以及精细化地理信息技术的应用。同时,细化的技术导则和规范的建立以及不同行业间的联合发文有力推动了气候信息的实际应用。此外,研究展示了近年开展的伊犁、深圳、北京实际案例主要内容。最后,针对未来我国将根据大气环流特征和生态环境承载能力、走优化城镇空间布局和城镇规模结构的新型城镇化道路,从工作层面和技术层面给出了需要不断完善并深入研究的几个重点。 相似文献
123.
利用天体引潮力周期变化模型和地面长波辐射(OLR)数据资料,分析2010~2011年云南、西藏地区的4次M5.0以上地震震前OLR异常,探讨了诱发地震的外部因素,即天体引潮力周期与红外异常发展的关联特征。结果显示:以临近发震时刻所在周期引潮力值最低点日期为OLR参照背景,获取的地震前后NOAA长波辐射OLR日增量分布图像显示:震中附近热异常明显,异常受构造控制,且其分布与断裂关系密切;异常演化经历起始-加强-高峰-衰减-再增强-发震-平静的过程,符合岩石因应力增加而破裂的规律。一方面表明地应力的临界状态演化过程可通过OLR辐射变化来反映。另一方面表明引潮力可以改变构造内部地应力的状态。 相似文献
124.
Characterisation of Soot Emitted by Domestic Heating,Aircraft and Cars Using Diesel or Biodiesel 总被引:1,自引:0,他引:1
Anne?Smekens Ricardo?Henrique?Moreton?Godoi Patrick?Berghmans René?Van?GriekenEmail author 《Journal of Atmospheric Chemistry》2005,52(1):45-62
The characterisation of aggregates, like soot, firstly requires the determination of the size distribution of the primary
particles. The primary particle size of combustion generated aggregates depends upon the combustion environment and the formation
conditions, such as temperature, pressure and fuel-to-air ratio, among others. Since the combustion characteristics are different
in the different types of burners, the characterisation of primary particles may offer the possibility to distinguish soot
from different sources. In this paper, we present the signature of the primary particles and the aggregates of soot emitted
by cars using diesel or biodiesel, by domestic heating, and by aircraft exhausts, which can be considered as the major sources
as derived from measurements on transmission electron micrographs. The size distributions of all aggregates types with different
aerodynamic diameter were log-normal and quasi-monodisperse. The size distribution of the primary particles for soot emitted
by different sources showed minor differences. However, a comparison between the diameter of the primary particles and those
obtained using a standard method for carbon black revealed discrepancies. The median diameter of the primary particles was
combined with the median number of primary particles in an aggregate to calculate the relative particle surface area available
for adsorption. In a similar way, the relative specific surface area was determined. The surface area was measured using the
Brunauer-Emmett-Teller (B.E.T.) nitrogen adsorption method and the relative surface area available for adsorption was calculated. 相似文献
125.
126.
Ramón A. López‐Pérez Luis E. Calderón‐Aguilera Héctor Reyes‐Bonilla José D. Carriquiry Pedro Medina‐Rosas Amilcar L. Cupul‐Magaña María D. Herrero‐Pérezrul Héctor A. Hernández‐Ramírez Miguel Á. Ahumada‐Sempoal Betsabe M. Luna‐Salguero 《Marine Ecology》2012,33(4):407-416
Corals in the Eastern Pacific extend south from the Gulf of California to Ecuador and oceanic Chile, and west from Colombia to Clipperton Atoll. Nevertheless, large stretches of the Mexican Pacific remain fundamentally unstudied. Therefore, to assess the current conditions of coral communities, a coastal fringe ~300 km long (17°40′ N, 101°39′ W to 16°46′ N, 99°49′ W) was surveyed within the Southern Mexican Pacific, between 2005 and 2009. Fifteen stony coral species were identified at 13 coral communities and six Pocillopora‐dominated fringing reefs, with Pocillopora verrucosa and Pocillopora damicornis the primary contributing taxa. Reef development was identified in embayments or behind rocks or islands that offered shelter from northern and northwestern winds. Observations of Pocillopora effusus, Pocillopora inflata, Porites lobata, Pavona clavus, and Pavona varians expanded the species known geographic ranges by several degrees of latitude, suggesting reef building fauna comprised a mixture of widespread and relatively rare Eastern Pacific corals. Results indicated greater live coral cover in the Ixtapa‐Zihuatanejo area (15–73%) than in the Acapulco localities, which had high algal dominance; the reefs in the latter region exhibited high erosion. Regional differences are likely the result of long‐standing anthropogenic pressures around Acapulco since 1950, when it became an important tourist destination. This paper is the first detailed report of ecologically stressed corals and coral reefs from the state of Guerrero on the Mexican Southern Pacific coast. 相似文献
127.
The economical and ecological importance of tidal inlets has fostered the development of empirical tools for inlet management during the last century. This study aims at confronting these empirical theories with results obtained with a process-based numerical model, MORSYS2D. This 2DH morphodynamic modeling system is applied to an idealized tidal inlet/lagoon system with different combinations of significant wave height, tidal range and tidal prism. The numerical model predictions are compared to the empirical models of Hayes, Bruun, O'Brien and FitzGerald and to morphologies observed at natural tidal inlets. The results present good accordance with observations as well as with some key behaviors predicted with the empirical theories. The predicted morphologies satisfy the relation of O'Brien between the tidal prism and the cross-sectional area, the model reproduces the conceptual model of sand by-passing by ebb-tidal delta breaching of FitzGerald and the classifications of Hayes and Bruun are generally respected. However, some inconsistencies between model results and Hayes classification highlight the limitations of applying this classification, which only considers the yearly-averaged significant wave height and tidal range, to a single tidal inlet case. 相似文献
128.
Evaluating the relationship between spatial heterogeneity and temporal variability of larval fish assemblages in a coastal marine ecosystem (Haizhou Bay,China) 总被引:1,自引:0,他引:1 下载免费PDF全文
Zengguang Li Zhenjiang Ye Rong Wan Yong Chen Yongjun Tian Yiping Ren Hong Liu Haisheng Hu Robert Boenish 《Marine Ecology》2017,38(6)
In coastal marine ecosystems, spatial patterns of larval fish assemblages (LFAs) tend to exhibit geographic stability because of relatively stable spawning site selection and predictable oceanographic phenomena such as eddies. To evaluate the relationship between spatial heterogeneity and temporal variability of LFAs, we conducted a high spatiotemporal resolution ichthyoplankton survey from April to July in 2013 in the shallow waters (<20 m) of Haizhou Bay, China. Our analysis indicated three distinct assemblages, which were stable geographically but exhibited a gradual and directional change of species composition and abundance over our study period. Sea surface temperature was the most important environmental co‐variate for determining temporal variability of LFAs, likely owing to temperature effects of species composition and spawning period selection of adult fish, along with known temperature‐dependent survival rates of larval fish. Study of LFA spatiotemporal dynamics is essential for improved understanding of adult fish spawning behavior, and has potential to inform design and implementation of conservation and management measures (e.g. marine protected areas) in coastal systems. 相似文献
129.
小黄鱼是我国近海四种最重要的经济鱼类之一,在过去的几十年中小黄鱼种群及其两个地理亚种群经历了巨大的变化。小黄鱼的种群动力学研究,对于维持这一重要渔业的可持续管理是至关重要的。目前仅有的两个小黄鱼种群动力学模型只涵盖了较短的时间,且没有关注其空间差异。本文研究了1968年至2015年间黄渤海和东海小黄鱼的种群动力学模型,包含和不包含空间分层结构的两种贝叶斯模型被用于分析其种群动力学的大尺度空间异质性。本文分析了不同的假设,来研究小黄鱼种群动力学潜在的变化趋势。研究结果表明小黄鱼种群动力学特征具有明显的时间和空间变化。种群的增长速度从20世纪八十年代开始增加,而可捕系数从1981年到2015年增加了两倍多。与黄渤海亚种群相比,东海的小黄鱼亚种群生长速度更快,遭受的捕捞压力也更大。基于最大可持续产量MSY的参考点表明,无论是整个小黄鱼种群还是两个亚种群,近年来都有非常高的过度捕捞风险。因此我国小黄鱼的渔业管理急需更加保守的管理策略,同时考虑其地域差异。本文所用的方法可以应用于其他种类的资源评估和渔业管理,尤其是具有空间异质性和数据有限的种类。 相似文献
130.
Abstract This document presents fundamental terms describing the transfer of radiative energy and relevant optical properties of natural waters. These are primarily based upon the terminology of the “Système International d'Unités (SI)”; and the “International Commission on Illumination (CIE).’’ Quantities and Symbols as proposed in the present terminology follow and extend the terminology that was recommended by the Committee on Radiant Energy in the Sea (of the International Association of Physical Oceanography, IAPO), as published by Jerlov (1968, Optical Oceanography Elsevier Oceanography Series, Vol. 5; 1976, Marine Optics Elsevier Oceanography Series, Vol. 14). 相似文献