红树共附生微生物分离与抗白色念珠菌活性评价

对湛江市廉江高桥、东简北港2个红树林区红树的根、叶、花、果不同部位27份样品进行共附生微生物的分离及抗白色念珠菌活性的评价。采用改良M1培养基、改良马丁培养基和改良高氏一号培养基进行细菌、真菌和放线菌的分离,用美蓝酶标仪法对所筛菌株进行抗白色念珠菌活性评价。利用SPSS13.0软件对数据进行单因素方差分析和多重比较。从27份样品中共分离出384株红树林共附生微生物,其中细菌170株,真菌160株,放线菌54株,细菌和真菌为优势菌群,两者占分离总菌株数的86.0%;从384株分离菌中检测出64株具有抗白色念珠菌活性,占分离菌的16.7%;统计分析显示,除2个地区的抗白色念珠菌活性数无显著差异外,2个地区的红树共附生微生物的组成、不同类型共附生微生物的数量、不同类型共附生微生物的抗白色念珠菌活性、红树不同部位的共附生微生物数量与活性菌株数量均存在一定的差异。     

海南岛北部地区红树林湿地土壤有机碳分布规律及影响因素

红树林是单位生产力最高的生态系统之一,能够持续地固定有机碳,对全球碳平衡及生物地球化学循环有深远影响。在海南岛北部东寨港、八门湾、新盈港地区等典型红树林湿地的林内、林缘和光滩开展垂直采样,共采集15个样点,在室内对样品的有机碳含量、物理化学性质进行分析,探讨红树林湿地土壤有机碳的分布规律以及影响碳储量的主要因素。结果显示:红树林湿地0～40cm土壤有机碳含量为0.88～134.00g/kg,平均为25.18(±10.34)g/kg。在空间分布上,表现为八门湾红树林(36.61g/kg±4.46g/kg)东寨港红树林(25.57g/kg±3.14g/kg)新盈红树林(13.36g/kg±1.71g/kg);水平分布规律为林内(41.69g/kg±0.71g/kg)林缘(21.24g/kg±0.43g/kg)光滩(13.88g/kg±0.32g/kg);垂直分布最大值出现在10～20cm土层,为32.11(±3.45)g/kg。进一步相关分析显示,土壤有机碳含量与粘粒和粉粒呈极显著正相关关系,与砂粒和pH值呈极显著负相关关系。     

宏基因组学在红树林土壤微生物研究中的应用

红树林的土壤微生物群落蕴藏丰富的自然资源,但传统研究方法复杂、低效,而且只能获得极不完全的小部分信息,近年来兴起的宏基因组学克服了这些缺点。介绍了宏基因学的主要研究方法,在此基础上总结了宏基因组学在红树林土壤微生物多样性、空间分布特征、土壤理化性质与微生物群落结构之间的关系、土壤微生物代谢产物4个方面的具体应用,最后对该领域未来的研究方向提出了展望。     

红树林生态系统遥感监测研究进展

随着现代遥感技术的迅速发展,遥感监测已经成为红树林生态系统变化监测的重要手段和方法。从遥感技术在生态系统变化监测应用领域入手,综述了国内外红树林遥感监测的发展历程,系统总结了遥感技术在红树林湿地动态、种间分类、群落结构(叶面积指数、冠幅、树高等)、生物量、灾害灾情(病虫害、风暴潮等)、景观格局动态、驱动力、红树林湿地保护与管理等领域应用现状,归纳了不同应用领域遥感监测的理论、方法及研究现状。指出我国在红树林遥感监测中存在的不足。提出红树林遥感监测应在分类标准体系规范化、分类精度提升、红树林生态学特征参数(物种多样性、优势度等)、生态系统环境空间演变过程及遥感监测的尺度效应方面加大研究力度。充分发挥区域综合监测模型在红树林生态系统变化遥感监测中的作用。     

广西红树林的数量分布

为摸清广西红树林的数量分布 ,采用遥感、GIS和GPS技术与地面调查相结合的方法对广西红树林进行了全面的调查 .在此基础上以自然海湾为研究单位 ,对广西红树林的空间分布、群落类型和覆盖度、树高等级等林分结构进行了分析评价 .结果表明 ,红树林在宏观上沿整个海岸线呈展开式均匀分布 ,在 14 89 64km海岸线中 ,间断距离 <2km的红树林岸段占海岸线总长度的 75 7% ;14个海湾中有 10个海湾的红树林岸线率≥ 80 % ;红树林分布由海岸 (堤 )向外海延伸 50～ 10 0 0m ,最远外延达 2 82 0m ;74 4%的红树林分布于海堤外侧 ;桐花树群落 (Comm .Ae gicerascorniculatum)、白骨壤群落 (Comm .Avicenniamarina)、秋茄—桐花树群落 (Comm .Kandeliacandel,Aegicerascornic ulatum)和白骨壤 +桐花树群落 (Comm .Avicenniamarina ,Aegicerascorniculatum )为优势群落 ;61 9%的红树林覆盖度≥70 % ;78 1%的红树林平均高度 <2 0m     

Coastal wetlands of the northern Gulf of California: inventory and conservation status

• 1. Above 28°N, the coastline of the northern Gulf of California is indented at frequent intervals by negative or inverse estuaries that are saltier at their backs than at their mouths due to the lack of freshwater inflow. These ‘esteros’ total over 215 000 ha in area and encompass mangrove marshes below 29°N and saltgrass (Distichlis palmeri) marshes north of 29°N. An additional 6000 ha of freshwater and brackish wetlands are found in the Colorado River delta where fresh water enters the intertidal zone.
• 2. The mangrove marshes in the Gulf of California have been afforded some degree of protected status in Mexico, but the northern saltgrass esteros do not have priority conservation status and are increasingly becoming development targets for resorts, vacation homes and aquaculture sites.
• 3. We conducted an inventory of the marshes using aerial photography and satellite images, and evaluated the extent and type of development on each marsh. We reviewed the available literature on the marshes to document their vegetation types and ecological functions in the adjacent marine and terrestrial ecosystems.
• 4. Over 95% of the mangrove marshes have been developed for shrimp farming. However, the farms are built adjacent to, rather than in, the marshes, and the mangrove stands are still mostly intact.
• 5. The majority of saltgrass marshes above the mangrove line are still relatively unspoiled. However, resort and vacation home development is taking place on land surrounding them.
• 6. We recommend a system of protected reserves incorporating the pristine wetlands, along with water quality management and buffer zones for the more developed esteros. The saltgrass marshes should be considered for conservation protection, similar to the protection given to the southern mangrove marshes whose value has already been recognized.

Copyright © 2006 John Wiley & Sons, Ltd.     

Effects of mangrove deforestation on fish assemblage at Pak Phanang Bay,southern Thailand

Daytime sampling using a seine net was conducted at Pak Phanang Bay (Nakhon Si Thammarat Province, Thailand) in February and July 2006, to determine differences in fish assemblage structures between a mangrove site and an adjacent site completely cleared of mangroves. The overall numbers of fish species and individuals were significantly higher at the mangrove site than the cleared site in both months. Although benthic crustacean feeders showed more species and individual numbers at the mangrove site in both months, the opposite was found for zooplankton feeders. A cluster analysis, based on the abundance of each species, demonstrated that the fish assemblage structures were distinctly different between the two sites. In addition, significant differences in length frequency distributions for each of the four most abundant species were found between the sites in February and/or July. Small individuals of Scatophagus argus, Ambassis nalua, and Tetraodon nigroviridis were more common at the mangrove site, and of Chelon subviridis at the cleared site. These results suggest that mangrove deforestation exerts marked effects on fish assemblages.     

Fishers’ ecological knowledge of sawfishes in Lake Piso,Liberia

相似文献   

Sawfishes in The Gambia and Senegal – shifting baselines over 40 years

相似文献   

深圳地区红树植物淡水种植试验

2004-2010年,在深圳地区进行了红树植物淡水种植及品种筛选试验。在红树植物育苗方面,7个受试品种(秋茄、桐花树、海漆、海桑、无瓣海桑、木榄和老鼠勒)均获得了成功,出苗率较好;在种植方面,9个品种(木榄、桐花树、海桑、无瓣海桑、秋茄、海漆、老鼠勒、银叶树和竹节树)均能在淡水环境中存活。海桑、无瓣海桑和竹节树生长较好,在构建淡水人工湿地时,应优先选用。在2008年冬季受到异常低温干扰时,有部分海桑植株死亡,但温度回升后,很快萌发新芽再生。秋茄和木榄生长缓慢,植株生长2～3年仍不能成林。海漆在水位变化大且沙泥质河滩地生长情况良好,对生境条件要求严格。桐花生长情况良好,在淡水环境条件下虽能开花,但结果不良。老鼠勒虽能存活,但长势不理想。