鄱阳湖枯水期延长背景下越冬水鸟群落结构、丰富度及其空间分布格局   总被引：1，自引：1，他引：0  

张娜  李言阔  单继红  涂小斌  张育慧  李跃  汪凌峰  应钦 《湖泊科学》2019,31(1):183-194

鄱阳湖是我国最大的淡水湖,也是具有国际意义的候鸟越冬地.本研究于2015和2016年越冬期对鄱阳湖越冬水鸟的群落结构、丰富度和空间分布进行了系统的调查,分别记录到水鸟494033和388017只,隶属于6目13科68种.雁形目和鸻形目鸟类种类最多,其次是鹳形目和鹤形目;从生态型来看,游禽32种,涉禽36种.雁鸭类相对丰富度最高,是鄱阳湖越冬水鸟的优势类群,其次是鸻形目鸟类,而2015和2016年鹤形目鸟类数量仅占当年总数量的2.6%和1.4%.在鄱阳湖湿地的不同区域,越冬水鸟种类组成差异较大.从空间分布来看,越冬水鸟主要集中在鄱阳湖自然保护区、九江湿地和南昌湿地.开展鄱阳湖越冬水鸟的种群数量调查,摸清越冬水鸟群落结构和种群丰富度现状,对于有针对性地开展越冬水鸟保护具有重要意义.  相似文献   

Mapping three-dimensional co-seismic surface deformations associated with the 2015 M_W7.2 Murghab earthquake based on InSAR and characteristics of crustal strain     

Jie GAN  Jun HU  Zhiwei LI  Changjiang YANG  Jihong LIU  Qian SUN  Wanji ZHENG 《中国科学:地球科学(英文版)》2018,(10)

Three-dimensional(3 D) co-seismic surface deformations are of great importance to interpret the characteristics of coseismic deformations and to understand the geometries and dynamics of seismogenic faults. In this paper, we propose a method for mapping 3 D co-seismic deformations based on InSAR observations and crustal strain characteristics. In addition, the search strategy of correlation points is optimized by adaptive correlation distance, which greatly improves the applicability of the proposed method in restoring deformations in decorrelation areas. Results of the simulation experiment reveal that the proposed method is superior to conventional methods in both the accuracy and completeness. The proposed method is then applied to map the 3 D co-seismic surface deformations associated with the 2015 MW7.2 Murghab earthquake using ascending and descending ALOS-2 PALSAR-2 images. The results show that the seismogenic fault is the Sarez-Karakul fault(SKF), which is dominated by NE-SW strike slips with an almost vertical dip angle. The north section and the south segment near the epicentre have obvious subsidence along with a southwestward motion in the northwest wall, and the southeast wall has northeast movement and surface uplift trend along the fault zone. The strain field of the earthquake is also obtained by the proposed method. It is found that the crustal block of the seismic area is obviously affected by dilatation and shear forces, which is in good agreement with the movement character of the sinistral slip.  相似文献   

几何校正对暗像元算法及离水辐亮度反演精度的影响:以太湖为例     

陈军  付军  孙记红 《湖泊科学》2011,23(1):89-94

几何校正将引起几何校正前后像元的像素值发生变化,进而导致暗像元的辐亮度在几何校正前后存在偏差.本文以太湖为研究水区,以2003年10月28日的Landsat/TM影像、2008年7月24日的CBERS影像和2009年4月25 日的HJ-1B影像作为数据基础,研究与探讨了几何校正对暗像元大气校正算法以及离水辐亮度反演精度...  相似文献   

米仓山构造带下寒武统筇竹寺组砂岩球状风化特征及成因机制     

师文文  杨兆林  尹洪荣  牛基宏  杜贵超  陈娟  陈奕阳  崔耀科 《世界地质》2022,(1):173-185

球状风化发育类型广泛,并且与人们的生产生活息息相关,但是人们对球状风化的研究却相对较少.为进一步研究其发育特征和形成机制,笔者通过薄片鉴定、扫描电镜、X-射线衍射、主量及微量元素分析等实验手段对米仓山构造带下寒武统筇竹寺组砂岩球状风化发育特征及成因机制开展了系统研究.研究表明,米仓山构造带下寒武统筇竹寺组砂岩的球状风化...  相似文献   

The safety study of heavy metal pollution in wheat planted in reclaimed soil of mining areas in Xuzhou, China   总被引：3，自引：1，他引：2  

Jihong Dong  Min Yu  Zhengfu Bian  Yindi Zhao  Wei Cheng 《Environmental Earth Sciences》2012,66(2):673-682

This study was conducted to evaluate crops cultivated in reclaimed soils from subsidence areas that had been reclaimed in the Liuxin mining area, Xuzhou, China, to determine if such crops were safe. To accomplish this, heavy metals such as Hg, Pb, Cu, Cd, Cr, Zn and As (metalloid) concentrations in different parts of wheat planted in the research area were detected. The single contamination index method and comprehensive contamination index method were used to estimate the level of heavy metal pollution in rhizosphere soil. Besides, the distribution of heavy metal concentrations in different organs of wheat of the research area was compared, and the enrichment coefficients of Cd and Cr, which as the primary pollutants, in different parts of wheat were determined and used to yield curve estimation, after which a Cd regression equation was constructed. Finally, a kind of visible expression method of heavy metal pollution in wheat was explored. The results showed that the rhizosphere soil of the research area reached the local standard, but as different organs of wheat differed in the ability of enrichment of heavy metals, the Cd and Cr concentrations in wheat grains exceeded the national food hygiene standard. The distribution and migration tendencies of Cd and Cr concentrations in different organs of mature wheat were consistent in reclaimed sites, but differed in control site. The Cd regression equation passed the model verification. The results of risk evaluation of Cd and Cr in the wheat grain revealed that the single contamination index of the three sites reached light to severe level, and the comprehensive contamination index ranged from light to medium pollution level. This research is of important practical value for monitoring the safety of plant grown in mining areas.  相似文献   

微弯河岸沿线扰动压强分布特性试验          下载免费PDF全文

林俊强  严忠民  夏继红 《水科学进展》2013,24(6):855-860

河岸沿线的压强梯度是河岸侧向潜流交换及河岸带物质和能量传递的主要驱动力。为揭示微弯河岸边界的扰动压强分布规律和主要影响因素,利用室内变坡水槽系统,制作不同体形的正弦形河道模型,实测一个周期波长的河岸表面压强水头,研究河岸不同分层、不同弯曲程度和不同水流条件下的沿线压强分布特性,并进行影响因素的敏感性分析。试验结果表明,在缓流条件下正弦形微弯河岸的沿线扰动压强分布呈曲线形波动,不同分层的压强分布规律大体相同。在河岸弯曲程度较小时,压强波动的峰值与谷值分别出现于凹岸和凸岸的曲率最大位置。河岸沿线扰动压强的变化主要受河岸振幅与波长比a/λ和来流弗劳德数Fr的影响,敏感性分析表明a/λ比Fr的影响更为显著。  相似文献   

鄂尔多斯盆地陇东地区延长组纵向储层质量差异及主控因素分析     

付晶  吴胜和  罗安湘  张立安  李桢  李继宏 《地学前缘》2013,20(2):98-107

综合应用多种岩心分析资料对陇东地区上三叠统延长组主力勘探目的层长8和长6油层组的岩石组构、岩石组分与储层质量差异进行了对比分析,探讨了岩石组构与岩石组分对储层质量差异的控制作用。长8末期一次显著的构造事件导致长8与长6油层组储层岩石组分和组构特征发生了明显的变化。相较于长8油层组,长6油层组粒度较细、杂基含量较高,使得原始渗透率较低,并导致更强的压实作用,使得其最终储层质量较差;塑性组分含量高,经历了较强的压实作用,原生粒间孔保存较少,并不利于后期溶蚀作用对储层进行改造;喷发岩岩屑含量低使储层早期绿泥石膜胶结相对不发育;富含白云岩岩屑为晚期含铁碳酸盐胶结物的形成提供了物质基础,使得长6油层组储层进一步致密化;长石含量高使得自生伊利石含量高,其形成的大量微孔隙导致了渗透率的大幅度降低。  相似文献   

南极阿德雷岛不同基底中真菌的分离培养及初步鉴定          下载免费PDF全文

靳永轩  丛柏林  王能飞  刘胜浩  沈继红  黄晓航 《极地研究》2013,25(1):71-77

为了探索南极真菌的多样性,进一步揭示其生态学角色和筛选有特定酶活性菌株,本研究对中国第27次南极科学考察采集自阿德雷岛的6份样品进行了真菌的分离培养及其胞外酶活性测定。从6份样品中共分离得到168株真菌,其中大型海藻腐烂物样品中分离到的真菌种类和数量最多,占所分离菌株总数的34.6%;对选取的15株代表菌株进行了真菌ITS1-5.8S-ITS2序列鉴定,结果表明它们分属于4个纲,8个属,其中青霉属5株,假散囊菌属、地丝菌属和枝孢属各2株,生赤壳属、曲霉属、出芽短梗霉属和unclassified Onygenales各 1株,该结果表明南极地区具有丰富的真菌物种多样性,其优势类群青霉菌。胞外酶测定显示产淀粉酶、蛋白酶和纤维素酶产生菌分别占供试菌株的64.6%、45.1%、14.6%,产纤维素酶的菌株可能在南极物质能量循环中扮演着重要角色。  相似文献   

Preliminary Study on the Relationship between the M_s8.0 Wenchuan Earthquake of 2008 and the Anomalies of Earth Resistivity Observed at Qingdao Seismic Station     

Zhang Jihong  Zhao Guoze  Wang Jinsheng  Tang Tingmei  Qi Lijie 《中国地震研究》2011,25(2):158-165

Near-surface earth resistivity and underground water level anomalies were recorded at Qingdao seismic observatory of Shandong Province before and after the MS8.0 Wenchuan Earthquake of May 12,2008.The observed data of earth resistivity at the observatory revealed that the underground water level dropped and the resistivity increased.It is postulated that in the special tectonic setting at Qingdao observatory,the variation of stress and strain caused the change of water level beneath the station,thus,leading...  相似文献   

海底未固结成岩地层体积密度的估算方法     

何静  刘学伟  杨萌萌  刘继红  谢城亮 《海洋地质与第四纪地质》2011,(5):155-161

为了获得无测井或岩心资料地区天然气水合物赋存海域未固结成岩地层的体积密度,对ODP164、ODP204、IODP311航次实际钻探资料进行了分析,统计了体积密度、孔隙度、颗粒密度的分布情况及其相互关系.分析结果表明,水合物赋存的未固结成岩地层孔隙度很高,一般大于40％,在此范围内体积密度主要受到孔隙度制约,而对骨架颗粒...  相似文献