重庆地区历史地震等震线长轴方位分布综合分析

统计了重庆地区历史地震等震线长轴方位分布,主要为NE向。通过对地震活动、活动断裂分布、震源机制解的统计特征分析,指出历史地震等震线长轴方位与活动断裂的走向、震源机制解的一个节面走向基本保持一致,三者之间可相互印证。在地震应急工作中可快速建立等震线模型,从而确定灾区面积。     

浅循环泉简析

泉按照出露原因通常可以分为侵蚀泉、接触泉、溢流泉（溢出泉）和断层泉等。根据泉眼和地下水循环深度（或径流位置）的相对关系,泉可以分为表层泉、浅循环泉和深循环泉。地下水在地下流动(循环)的最深处仍然高于泉口,这类泉称为浅循环泉。浅循环泉出露的位置并不在地形最低处,其补给来源主要是大气降水入渗,地下水受到重力作用自高处往低处流动,在地下径流的途径短、时间短,流量一般不大。浅循环泉通常是常温泉、淡水泉（也有咸泉和盐泉）,多是常年性泉,也有部分是季节性泉或暂时性泉。广西北竂岭北坡泉和云南顺荡井盐泉是典型的浅循环泉。     

地震灾害人员死亡评估模型对比—以甘肃省中强震为例

梳理了现有3种地震灾害人员死亡评估模型,并基于甘肃地区历史中强地震(MS4.7～6.0),对人员死亡评估模型进行震例计算.结果表明:①针对甘肃地区中强地震,3种模型的评估结果与实际结果基本处于同一数量级,可用于地震后快速盲评估计算,为地震后政府和应急管理部门应急指挥决策提供科学依据;②当中强地震震中烈度达到Ⅷ度时,这3...     

Spatial patterns and environmental associations of deep scattering layers in the northwestern subtropical Pacific Ocean

The mesopelagic communities are important for food web and carbon pump in ocean, but the large-scale studies of them are still limited until now because of the difficulties on sampling and analyzing of mesopelagic organisms. Mesopelagic organisms, especially micronekton, can form acoustic deep scattering layers (DSLs) and DSLs are widely observed. To explore the spatial patterns of DSLs and their possible influencing factors, the DSLs during daytime (10:00–14:00) were investigated in the subtropical northwestern Pacific Ocean (13°–23.5°N, 153°–163°E) using a shipboard acoustic Doppler current profiler at 38 kHz. The study area was divided into three parts using k-means cluster analysis: the northern part (NP, 22°–24°N), the central part (CP, 17°–22°N), and the southern part (SP, 12°–17°N). The characteristics of DSLs varied widely with latitudinal gradient. Deepest core DSLs (523.5 m±17.4 m), largest nautical area scattering coefficient (NASC) (130.8 m2/n mile2±41.0 m2/n mile2), and most concentrated DSLs (mesopelagic organisms gathering level, 6.7%±0.7%) were observed in NP. The proportion of migration was also stronger in NP (39.7%) than those in other parts (18.6% in CP and 21.5% in SP) for mesopelagic organisms. The latitudinal variation of DSLs was probably caused by changes in oxygen concentration and light intensity of mesopelagic zones. A positive relationship between NASC and primary productivity was identified. A four-months lag was seemed to exist. This study provides the first basin-scale baselines information of mesopelagic communities in the northwest Pacific with acoustic approach. Further researches are suggested to gain understandings of seasonal and annual variations of DSLs in the region.     

广西涠洲岛滨海湿地潮下带海草、红树林与互花米草的分布和群落结构特征

系统报道了广西涠洲岛的潮下带海草、红树林以及互花米草的分布和群落结构特征.2019—2020年的调查结果表明,涠洲岛海草分布于南湾西侧,紧邻珊瑚礁区,面积4246 m2,为潮下带的生长形式,海草种类仅见卵叶喜盐草(Halophila ovalis);真红树植物有6种[红海榄(Rhizophora stylosa)、海漆...     

The globular clusters–stellar haloes connection in early-type galaxies

This paper explores if, and to what an extent, the stellar populations of early-type galaxies can be traced through the colour distribution of their globular cluster (GC) systems. The analysis, based on a galaxy sample from the Virgo Advanced Camera for Surveys data, is an extension of a previous approach that has been successful in the cases of the giant ellipticals NGC 1399 and NGC 4486, and assumes that the two dominant GC populations form along diffuse stellar populations sharing the cluster chemical abundances and spatial distributions. The results show that (a) integrated galaxy colours can be matched to within the photometric uncertainties and are consistent with a narrow range of ages; (b) the inferred mass to luminosity ratios and stellar masses are within the range of values available in the literature; (c) most GC systems occupy a thick plane in the volume space defined by the cluster formation efficiency, total stellar mass and projected surface mass density. The formation efficiency parameter of the red clusters shows a dependency with projected stellar mass density that is absent for the blue globulars. In turn, the brightest galaxies appear clearly detached from that plane as a possible consequence of major past mergers; (d) the stellar mass–metallicity relation is relatively shallow but shows a slope change at   M _*≈ 10¹⁰ M_⊙  . Galaxies with smaller stellar masses show predominantly unimodal GC colour distributions. This result may indicate that less massive galaxies are not able to retain chemically enriched interstellar matter.     

Web-GIS tool for the management of rural land markets

Land abandonment and stagnation of rural markets in the last few years have become one of the main concerns of rural administrations. The use of Web and GIS (Geographic Information System) technologies can help to mitigate the effects of these problems. This paper pro-poses a novel Web-GIS tool with spatial capabilities for the dynamization of rural land markets by encouraging the transfer of land from owners to farmers through the leasing of plots. The system, based on open source software, offers information about the properties, their environment and their owners. It uses standards for handling the geographic information and for communicating with external data sources. This system was used as the basis for the development of SITEGAL, the tool for the management of the Land Bank of Galicia (www.bantegal.com/sitegal). SITEGAL has been operational since 2007 obtaining benefits for both administration and users (farmers and land owners), and promoting the e-Government.     

Short-Term Benthic Recolonization after Dredging in the Harbour of Ceuta, North Africa

Abstract. The benthic recovery after dredging (area: 2625 m²) was studied in a polluted and enclosed area of the harbour of Ceuta, in which the recolonization through the water column (larvae and adult bedload transport) could be limited by the lack of renewal. The benthos was sampled at two sites (control and dredged) using a van Veen grab and adopting a BACI (Before, After, Control, Impacted) approach. Five samplings were conducted after dredging (3, 15, 30, 90, 180 days). The proportion of gravel in the sediment of the dredged site increased after dredging, while the organic matter decreased. The impact on the community was estimated at species level, using both univariate and multivariate analyses. The maximum negative effect on benthic macrofauna was a reduction by 65% for species richness (15 days after dredging) and by 75% for abundance (3 days after dredging). Between 15 and 30 days after dredging, the abundance of some species such as the molluscs Parvicardium exiguum and Retusa obtusa and the polychaete Pseudomalacoceros tridentata increased considerably in the dredged site, while typical ‘opportunistic’ species such as Capitella capitata were disfavoured by the disturbance. For this small‐scale dredging, about 6 months are required for the disturbed area to re‐establish a sediment structure and a macrobenthic community similar to the undisturbed area. Small‐patch dredging operations are proposed in harbour management whenever possible, since they allow a quick re‐adjustment of the initial sediment structure and benthic communities.     

SZF型方位传感器方位定标测试方法

文中简要介绍了SZF型方位传感器的主要组成及工作原理,针对方位传感器在实验室内如何定标与测试给出了行之有效的计算机自差校正方案及实施方法,经过了大量的实际应用,该方法已经成为SZF型传感器的定标测试过程的重要步骤.     

利用不同地表比辐射率对ETM＋数据地表温度反演对比研究

地表温度作为研究环境生态影响的一个重要指标之一,以Landsat ETM+的热红外波段作为数据源,辅助大气透过率、大气平均气温等参数,利用单窗算法基于混合像元、NDVI、植被和裸露地三种不同地表比辐射率反演泉州市地表温度,对比分析结果表明采用这三种地表比辐射率反演地表温度的方法均是可行的,对于具体采用哪一种地表比辐射率应需要结合实际的研究区域地表地物的实际监测地表温度进行对比后,方可选择合适的地表比辐射率进行地表温度反演,会更具实际意义。反演结果可为城市热岛效应等研究提供支持数据源。