首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
海南岛红树林体系与发展思路   总被引:4,自引:0,他引:4       下载免费PDF全文
红树林是热带海岸地带一种重要的湿地类型和重要的生态系统,处于海洋与陆地的动态交界面,周期性遭受海水浸淹的潮间带环境,是不同于陆地生态系统,也不同于海洋生态系统的独特的海陆边缘生态系统。红树林有“海上森林”、“海底森林”、“海岸卫士”、“海水淡化器”等美称,与珊瑚礁、盐沼、上升流并称  相似文献   

2.
中国红树林生态系统的植物种类、多样性、功能及其保护   总被引:28,自引:0,他引:28  
本文从4个方面对中国红树林生态系统的植物进行论述:(1)中国红树林生态系统的红树植物、半红树植物、伴生植物、红树林区的大型藻类和浮游植物种类;(2)中国红树林生态系统植物的物种多样性、红树植物生理和形态适应的多样性、产物的多样性;(3)红树林的生态功能;(4)中国红树林生态系统的主要保护问题及其保护措施。  相似文献   

3.
文章综述我国红树林资源的历史变化,以及各地区红树林的空间分布、种类组成、面积变化及其主要原因等;归纳影响我国红树林生态系统健康状况的主要因素,包括环境污染、过度养殖、海洋工程、过度捕捞和生物入侵等。针对我国红树林现状及存在的问题,从红树林保护立法、环境综合整治管控、宣传教育、转产转业、生态补偿、生态修复等方面提出红树林保护的建议和措施,为我国红树林生态系统保护与管理提供参考。  相似文献   

4.
红树林生态系统作为全球重要的生态系统,将其服务功能价值进行科学的量化评估,能为其规划开发提供可靠的科学依据,保证资源的有效利用。在阐述分析红树林生态系统的多种生态服务功能的基础上,介绍生态服务功能的价值评估方法,分析各种功能类型评估方法的适用性,并以广东省红树林生态系统为例,对其服务功能价值进行评估。  相似文献   

5.
红树林污染生态学研究进展   总被引:16,自引:1,他引:16  
红树林生长在热带、亚热带陆海交汇的海湾河口区。随着工农业、沿岸城市开发及港口驳岸海运的发展 ,大量的环境污染物汇集于河口海湾区 ,冲击了红树林生态系统。红树林作为河口海区生态系统初级生产者支撑着广博的陆域和海域生命系统 ,为海区和陆缘生物提供食物来源 ,也为鸟类、昆虫、鱼虾贝类、藻菌等提供栖息繁衍场所 ,并构成复杂的食物链和食物网关系。因此有关红树林污染生态学问题已成为目前红树林研究中新的重要领域之一[1]。国内外学者对红树林生态系中多种环境污染物的环境行为和生态效应展开了研究 ,其中重金属、石油、人工合成…  相似文献   

6.
基于VSD模型的铁山港湾红树林生态系统脆弱性初步评价   总被引:2,自引:0,他引:2  
基于脆弱性域图 (vulnerability scoping diagram, VSD)评价模型, 从暴露程度、敏感性、适应能力3个方面构建了红树林生态系统脆弱性评价指标体系。采用改进的综合指数法和模糊综合评价法, 重新定义脆弱性分级标准, 定量评价了铁山港湾红树林生态系统在1989年、2003年和2014年3个年份的脆弱性水平。结果显示, 铁山港湾红树林生态系统在3个年份的脆弱性水平值分别为0.145、0.255、0.334, 呈现增加趋势。首先, 铁山港湾红树林生态系统面临的暴露程度不断增大, 主要胁迫因子为滩涂围垦面积、废水排放量; 其次, 生态系统的敏感性增强, 主要敏感因子是海洋生物质量综合指数、底栖生物和潮间带生物多样性指数; 第三, 生态系统的适应能力略有增加, 总体上较弱。  相似文献   

7.
红树林生态系统重金属污染的研究   总被引:27,自引:2,他引:25  
王文卿  林鹏 《海洋科学》1999,23(3):45-48
红树林是热带、亚热带海湾河口生态系统的重要初级生产者,对维护海湾河口地区的生态平衡起着十分重要的作用[6]。由于人口的增加,城市和工业的发展,进入红树林区的了农业废弃物和废水不断增多,所以必须了解这些废弃物及废水对红树林的作用及红树林生态系统是如何捕集这些污染物的。对于红树林沼泽作为废物、污水自然处理厂已引起关注[18,19],但目前对红树林区重金属污染尚无系统的研究,有关的认识主要是间接的。1 红树植物对重金属耐性的研究了解有关红树植物重金属耐性研究出发点有二:一是由于利用生物指示种检测海洋环…  相似文献   

8.
红树林生态系统处于海洋与陆地的动态交界面,遭受海水周期性浸淹,因而在结构与功能上具有既不同于陆地生态系统,也不同于海洋生态系统的特性。红树林作为初级生产者,为林区动物、微生物提供食物与营养,为鸟类、昆虫、鱼虾等提供栖息、繁衍场所。因此,红树植物对维护生态平衡、保护海岸生态系统起着重要的作用[1-2]。近年来由于工农业的发展,沿海城市人口与经济的增长,大量的污染物汇集于河口、海湾区,使这些地区的重金属污染日趋严重,特别是在直接向红树林区倾污排废的地区更是如此。  相似文献   

9.
广西北仑河口国家级自然保护区综合价值的研究   总被引:4,自引:0,他引:4       下载免费PDF全文
通过对广西北仑河口国家级自然保护区红树林的生态环境、资源现状、保护价值等方面进行系统分析,揭示该保护区红树林生态系统的功能作用,并提出加快保护区建设的重要意义。  相似文献   

10.
九龙江口红树林对汞的循环和净化作用   总被引:21,自引:0,他引:21  
林鹏  陈荣华 《海洋学报》1989,11(2):242-247
红树林是存在于海陆交汇处的生态系统,其间大量的凋落物中有一部分仍留在群落内,再加上上游有机物的输入,使得红树林沼泽形成高腐殖质的还原环境,沉积物中的总汞含量和有机质含量呈正相关[1],而大量的硫化氢又易与汞形成难于溶解的硫化汞,因而红树林区有可能是潜在的重金属富集区[2].本文对我国几个红树林区的汞本底值进行调查,研究汞在九龙江口秋茄群落的分布、迁移积累的途经,以及红树林对河口区汞循环的影响,并探讨红树林对汞污染净化作用的途经.  相似文献   

11.
Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium ( 〈 0.4 μm) exis- ted in the low molecular mass fraction ( 〈 10 000 u), and the colloidal uranium-238 (10 000 u -0.4 μm) only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases ( 〉 0.4 μm), the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows: 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows : 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value (1.0). The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic  相似文献   

12.
夏季珠江口沉积物中营养盐剖面分布和界面交换通量   总被引:21,自引:4,他引:21  
通过对夏季珠江口区域沉积物间隙水营养盐剖面分析,调查了营养盐含量分布和特征,探讨了有机物的降解特性、营养盐的底部通量估算和作用.结果表明,珠江口沉积物间隙水中营养盐以高含量铵盐为主要的存在形式,沉积物中有机物的降解反应主要在厌氧状态下进行,底部水体铵盐的增加来源于底部沉积物有机质的降解释放,而且对水体的营养盐循环有较大的贡献.  相似文献   

13.
In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future.  相似文献   

14.
湄洲湾夏季的初级生产力   总被引:2,自引:3,他引:2  
王宪  李文权 《台湾海峡》1994,13(1):8-13
湄洲湾1992年夏季的叶绿素a,三磷酸腺苷,碳比积累速率,初级生产力的变化范围和均值分别为0.45-4.72,1.49mg/m^3;0.12-1.07,0.31μg/dm^3;0.06-0.58,0.34d^-1;0.07-0.34,0.21m/(m^2.d)。叶绿素a与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素a三磷本能腺苷的比值为4.8,湄洲湾夏季浮游植物的生长受氮不足  相似文献   

15.
Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas.  相似文献   

16.
17.
Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements.  相似文献   

18.
对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。  相似文献   

19.
In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (Kd) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate.  相似文献   

20.
中国科学院海洋研究所建所70年来,在海洋贝类分类学研究领域取得了长足发展与进步,做出一系列开创性研究成果。本文综述了建所以来我所海洋腹足类分类学研究方面的主要进展,概述了取得的主要科研成果,分析了现代腹足类分类学研究的发展趋势以及面临的挑战,并对今后的发展提出了相应对策和建议。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号