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1.
根据2001年铜陵江段水域及铜陵半自然水域的水质理化进行测定分析,并对这些指标进行了统计分析和比较,结果表明:半自然水域与长江水质指标中的D0、NH3-N、大肠菌群的年均值差异不显著(P>0.05),而其他项目的年均值差异较显著(P<0.05).  相似文献   

2.
长江江豚迁地保护概述   总被引:3,自引:0,他引:3  
长江江豚(Neophocaena phocaenoides asaeorientalis)是江豚的扬子亚种,目前其种群数量已经不足1 400头,处于十分濒危的状况.其生态环境受到人为极大的影响,且在可预见的将来没有好转的迹象,因此,迁地保护长江江豚被认为是最有希望避免其灭绝的保护策略.目前,中国科学院水生生物研究所在室内豚池、石首天鹅洲白豚国家级自然保护区和铜陵淡水豚国家级自然保护区在半自然水域均构建了长江江豚迁地保护种群.该文概述了40多年来国内长江江豚迁地保护的成果及现状,探讨了今后开展迁地保护工作应注意的重点问题.做好长江江豚的保护工作,建立更多的迁地保护区是根本措施;开展长江江豚繁殖学研究是主要对策;规范和统一保护行动是有效途径.  相似文献   

3.
长江江豚     
江豚(Neophocaenaphocaenoides),是鼠海豚科仅有的一种,有3个亚种:分布于印度洋沿岸及香港的印度洋江豚;分布于长江、湘江和赣江的长江江豚;分布于韩国及日本的东亚江豚。  相似文献   

4.
长江江豚保护生物学研究进展   总被引:2,自引:0,他引:2  
近年来研究表明长江江豚(Neophocaena phocaenoides asiaeorientalis)是江豚(Neophocaena phocaenoides)的一个亚种,其种群数量明显减少,栖息地正在丧失。我国已有长江江豚30年饲养实践经验,建立长江豚类自然保护区,同时开展长江江豚饲养下的行为学与繁殖学研究,是保护本种积极有效的措施。  相似文献   

5.
长江江豚慢性皮肤炎症的初报   总被引:1,自引:0,他引:1  
报道了刚捕获的营养不良的幼年长江江豚,在人工饲养环境中遭条件致病菌侵袭后,左侧胸鳍脓肿,溃烂,结果导致江豚严重脱水、消瘦.采取隔离观察,灌液和静脉注射左氧氟沙星是治疗的主要手段.  相似文献   

6.
半自然条件下群体江豚的养护与行为观察   总被引:6,自引:2,他引:6  
长江江豚目前数量不足 2 0 0 0头 ,由于长江生态环境的日趋恶化 ,其种群数量仍在进一步下降之中 ,拯救工作因此更为迫切。本文报道了 1 992年至 1 996年在我场半自然状况的夹江中生活的江豚群体的饲养和伤病防治工作以及生态行为观察结果。  相似文献   

7.
长江中下游近30年来湖泊的水域面积变化研究   总被引:2,自引:0,他引:2  
利用多期地形图和遥感影像数据(Landsat TM/ETM),在地理信息系统平台上获取长江中下游主要湖泊的水域面积时空变化,并对其进行了研究分析.结果表明,长江中下游主要湖泊的总水域面积,在1971-1988年减少了2 544.51km2 ,1988-2000年减少了1 151.97km2.湖泊水域面积的减少是自然因素和人类活动综合作用的结果,围湖利用是湖泊水域面积减少的主要原因.  相似文献   

8.
通过对国内外自然水域游泳救生员培训管理的比较研究,针对国内自然水域救生存在的问题与不足提出建议性对策,为更好地促进游泳救生员职业化进程提供一定的理论参考.  相似文献   

9.
水域大地电磁测深中水体对电磁场的影响   总被引:1,自引:0,他引:1  
通过研究层状介质条件下水面与水底电磁场的关系,计算了电磁场的衰减关系式,获得水体对电磁场信号产生的衰减规律和在电磁信号分离采集的水域大地电磁测深勘探中对实测数据的改正方法。研究结果表明:频率越高、水体的电阻率越低,电磁场信号衰减越严重,但水体对电场信号和磁场信号的衰减特征不同,在同等条件下,磁场信号的衰减幅度远大于电场的衰减幅度,且受影响的频率范围也较宽,电场信号的衰减主要取决于水体本身的电阻率和深度,而磁场信号的衰减不仅与水体本身的电阻率、深度有关,还与水体下方介质特征有关,水下介质的电阻率越高,磁场的衰减越严重;在电磁信号分离采集的水域电磁测深勘探中,水域影响可忽略的条件是:使用MT法时水体深度应小于3 m,使用CSAMT法时水体深度应小于2 m。  相似文献   

10.
针对长江漫滩高承压水地基,以南京市某工字型地下6层地铁换乘站基坑为依托工程,采用FLAC3D三维有限差分软件,分别对半顺作半逆作开挖法和明挖顺作法进行数值模拟,分析了基坑开挖及降水的应力渗流耦合作用对周围地表沉降、连续墙侧移和支撑轴力的影响。结果表明:1)长江漫滩高承压水地基深基坑开挖工程,地表沉降值和连续墙变形值均较大;2)工字型深基坑开挖工程,地表沉降、连续墙侧移最大值出现在上下横边中点处;3)半顺作半逆作法的地表沉降、连续墙侧移、横向支撑轴力值均小于明挖顺作法,更有利于控制基坑侧壁变形,降低基坑开挖风险。  相似文献   

11.
To estimate the genetic diversity in the Yangtze finless porpoise ( Neophocaena phocaenoides asiaeorientalis), the randomly amplified polymorphie DNA technique was applied to examine ten animals captured from the Yangtze River. Out of 20 arbitrary primers used in the experiment, seventeen produced clearly reproducible bands. Calculated by Nei‘s formula d = 1-NAB/NT, the genetic distances ranged from O. 0986 to O. 5634. Compared with other cetacean populations, this genetic distance is quite low.Such a low genetic diversity suggests that this population may be suffering from reduced genetic variation,and be very fragile. More studies are needed for understanding the basis for this apparent low genetic diversity and to help protect this endangered, unique population.  相似文献   

12.
Study on the sex-related AFLP marker of the Yangtze finless porpoise   总被引:1,自引:0,他引:1  
The sex-related molecular marker of the Yangtze finless porpoise was screened using Amplified Fragment Length Polymorphism (AFLP) technique combined with the bulked segregant analysis. Totally 36 AFLP primer combinations were used to detect the genome DNA bulks of the female and male porpoises, and one sex-related AFLP marker was finally obtained. The marker can be applied to sex identification, and provides a base for further cloning of sex-related genes and analyzing of Y chromosome haplotypes of the Yangtze finless porpoise.  相似文献   

13.
Population status, threats and conservation of the Yangtze finless porpoise   总被引:5,自引:0,他引:5  
The Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) is currently limited to the middle and lower reaches of the Yangtze River from Yichang to Shanghai, China, and the adjoining Poyang and Dongting Lakes. Its population size has decreased remarkably during the last several decades due to the heavy impact of human activities, including overfishing of prey species, water development projects that cause attendant habitat loss and degradation, water pollution, and accidental deaths caused by harmful fishing gear and collisions with motorized vessels. It was estimated that the number of remaining individuals was down to approximately 1800 in 2006, a number that is decreasing at a rate as high as 5% per year. Three conservation measures - in situ and ex situ conservation and captive breeding have been applied to the protection of this unique porpoise since the early 1990s. Seven natural and two "semi-natural" reserves have so far been established. Since 1996, a small group of finless porpoises has been successfully reared in a facility at the Institute of Hydrobiology of the Chinese Academy of Sciences; three babies were born in captivity on July 5, 2005, June 2, 2007 and July 5, 2008. These are the first freshwater cetaceans ever born in captivity in the world. Several groups of these porpoises caught in the main stream of the Yangtze River, or rescued, have been introduced into the Tian'e-Zhou Semi-natural Reserve since 1990. These efforts have proven that, not only can these animals survive in the area, they are also to reproduce naturally and successfully. More than 30 calves had been born in the reserve since then, with one to three born each year. Taking deaths and transfers into account, there were approximately 30 individuals living in the reserve as of the end of 2007. Among eight mature females captured in April 2008, five were confirmed pregnant. This effort represents the first successful attempt at off-site protection of a cetacean species in the world, and establishes a solid base for conservation of the Yangtze finless porpoise. A lesson must be drawn from the tragedy of Chinese River Dolphin (Lipotes vexillifer), which has already been declared likely extinct. Strong, effective and appropriate protective measures must be carried out quickly to prevent the Yangtze finless porpoise from becoming a second Chinese River Dolphin, and save the biodiversity of the Yangtze River as a whole.  相似文献   

14.
Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.  相似文献   

15.
铜陵江段豚类资源与保护措施的研究   总被引:6,自引:1,他引:6  
铜陵江段是长江下游唯一常年能发现白暨豹Lipotes uexillifer,且为长江江豚Neophocaena phcaenoides asaeorien-talis种群数量最集中,密度最大的江段,利用铜陵白暨豚养护场现有的条件,建立铜陵淡水豚自然保护区,在半自然水域中开展豚类人工饲养是保护白暨豚和长江江豚的有效途径。  相似文献   

16.
建立铜陵淡水豚自然保护区考察研究   总被引:10,自引:2,他引:10  
报道了铜陵江段白鱀豚 (Lipotesvexillifer )和长江江豚 (Neophocaenaphocaenoidesasiaeorientalis)资源现状及影响豚类生存制约因子 ,提出建立铜陵淡水豚自然保护区 ,加强栖息地保护 ,具有良好的生态效益和社会效益。  相似文献   

17.
广东自然保护区空缺性分析   总被引:2,自引:0,他引:2  
森林生态系统、湿地生态系统、陆生野生动植物是广东陆地国土的主要自然保护区类型.截至2004年底,自然保护区总面积占全省国土陆地面积的5.75%.文章在分析已建自然保护区基础上,从生态系统类型、生物多样性、区域布局体系方面研究全省自然保护区空缺.  相似文献   

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