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21.
Jinhua Pan Xin Jiang Xiaojie Li Yizhou Cong Zhuangzhi Zhang Zhiling Li Weili Zhou Houwei Han Shiju Luo Guanpin Yang 《中国海洋大学学报(英文版)》2011,10(2):147-152
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive
research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially
useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination
to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination
rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45,
increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA)
(P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly
increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination
rate at 14°C (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results
provide useful information for the propagation of artificial seedlings for seagrass restoration in China. 相似文献
22.
广西防城港东湾红树林污损动物的种类组成与数量分布特征 总被引：5，自引：0，他引：5
对白骨壤(Avicennia marina)树上的污损动物进行了定性和定量调查。共采得污损动物9种。以白条地藤壶(Euraphia withersi)和潮间藤壶(Balanus littoralis)在多数采样点的附着密度最高，但二者在树上的分布有明显的差异；团聚牡蛎(Ostrea glomerata)分布最广，是惟一～种在各采样点均能采到的污损动物；黑养麦蛤(Xenostrobus atraus)主要分布在树干和较粗的枝条上，其密度在向海林缘达到最大，超过牡蛎和藤壶的附着密度。污损动物附着高度与树高的比值(h：H)，主干、枝条和叶片上附着的污损动物总量均随林带离岸距离增大而增大，呈明显的变化趋势。 相似文献
23.
粤港澳大湾区作为国家战略,在“推进生态文明建设”方面明确提出了要“打造生态防护屏障”。东莞市滨海湾新区位于大湾区珠江口东岸,是大湾区几何中心和珠江口城市群连接点,规划为未来新城中心,其河口海岸生态修复具有典型意义。文章通过文献综述、资料梳理和规划分析等方法,从东莞滨海湾新区河口海岸自然环境现状出发,在分析其生态环境存在的问题的基础上,提出滨海湾新区应以河口海岸自然环境特征为基础,在保障河口行洪纳潮安全的前提下,对接海陆功能,开展沿海岸线的生态修复工程,打造东莞滨海湾新区“一堤一港一岛一廊多园”的生态海岸带,建设珠江河口“美丽湾区”。建议粤港澳大湾区河口海岸开展生态修复应以安全性为第一要素,因地制宜实施精细化修复,探索岸线异地修复制度,实现以“生态空间”支撑“发展空间”。 相似文献
24.
本文选取抑食金球藻(Aureococcus anophagefferens)、中肋骨条藻(Skeletonema costatum)和海洋卡盾藻(Chattonella marina)三种藻在20℃和25℃下进行单种、两种或三种藻间的培养实验, 探究在不同温度下藻种间的相互作用和竞争优势。单种培养结果显示抑食金球藻和中肋骨条藻对温度25℃敏感, 其环境容量(K)被显著降低; 而海洋卡盾藻的內禀增长率(r)在25℃下显著升高, 但K保持不变。在共培养中, 海洋卡盾藻在20℃下因抑食金球藻添加致死, 但在25℃处理下其K值上升120%。虽然中肋骨条藻的r在两个温度下均受海洋卡盾藻添加的促进, 但其K值从20℃下的上升43%转变为25℃下的降低48%。温度变化对于抑食金球藻和中肋骨条藻共培养的结果无明显影响, 中肋骨条藻的K均上升40%, 而抑食金球藻的K值均下降60%~70%。结果说明, 种间竞争除了共培养藻固有的相互作用关系因素外, 也受到微藻间温度适应性差异的影响。在20℃条件下三种藻混合, 抑食金球藻K的抑制率达到最高为79%, 而中肋骨条藻K的促进率达到最高为108%, 这可能表明三者之间的相互作用存在协同效应。 相似文献
25.
The relationships between reproductive allocation and different factors have been widely recognized for terrestrial plants, but scarcely for marine angiosperms. Focusing on the seagrass Zostera marina, we examined the change in biomass when it was partitioned to growth, vegetative propagation and reproductive allocation of Z. marina. We also evaluated the relationships between reproductive allocation and biotic and abiotic conditions in the coastal areas of north China. The results indicated that the reproductive allocation of Z. marina at the levels of genet, shoot and spathe was positively correlated with shoot characteristics such as height and biomass(P < 0.01), but was negatively correlated with branch number and leaf number per genet(P < 0.01). In addition, the allocation was also affected by other abiotic factors such as water column phosphate concentration(P < 0.05) and sediment total petroleum(P < 0.01). These findings indicated that both biotic and abiotic conditions significantly influenced the reproductive allocation of Z. marina, which may affect further the population dynamics. 相似文献
26.
The plant reproductive effort, the seed germination rate and the seedling survival and development of Zostera marina (eelgrass) were assessed in four populations (Fuzeta, Culatra, Barrinha and Armona) at the species’ southern distribution limit in the Eastern Atlantic, the Ria Formosa lagoon. Germinated seeds were individually placed in Petri dishes with natural sandy sediments and kept in a culture chamber at the same temperature and salinity conditions as the natural environment. In addition, seeds from three different depths of Fuzeta population were cultivated in outdoor mesocosms. The populations of Fuzeta and Barrinha showed higher seed production and the seeds produced were heavier than the other populations. The germination of the seeds both in the laboratory and in the outdoor tanks began c. 8–12 weeks after the collection of the flowering shoots at a water temperature of 22 °C. The spontaneous germination in the laboratory (2.4–5.3%) and in the mesocosm experiment (5.6–8.9%) was low and from all the germinated seeds (n = 20) only three reached the seedling stage. The spontaneously germinated seeds from Fuzeta survived for a longer period than those from Barrinha, but only the germinated seeds of Barrinha reached the seedling stage (one‐leaf seedling stage). In outdoor tanks, higher seed germination and earlier seedling emergence (2 weeks after seeding) and survival (for 208 days) occurred for the seeds obtained from the shallow meadow. The reproductive effort of Z. marina populations of Ria Formosa showed that flowering shoots and seed traits are site‐specific. The low reproductive success indicated by the low germination and seedling survival suggests a bottleneck in the species’ reproductive cycle that may account for the scarce presence of the species in Ria Formosa lagoon. The high water temperatures of Ria Formosa in winter may partly explain this bottleneck. Increased temperatures due to climate change may reduce even further the sexual reproduction of Z. marina in its southern distributional limit in the Eastern Atlantic. 相似文献
27.
The eelgrass Zostera marina is a key structural and functional species across the European coastline. The separate and interactive effects of eelgrass canopy removal and sediment addition on the sediment characteristics and the structure of benthic communities were studied in a factorial field experiment in the Northern Baltic Sea in July–August 2006. The removal of eelgrass canopy temporarily increased the sediment oxygen consumption, reduced the content of fine particles (<100 μm) and organic matter in the sediment, and increased the share of sand fraction (250–500 μm). Sediment addition increased the content of fine particles (<100 μm) and reduced the share of sand fraction (250–1000 μm). The effects were strongest in the presence of eelgrass canopy. Benthic invertebrates and macroalgae were affected by eelgrass canopy removal but not by sediment addition. The removal of eelgrass canopy significantly decreased benthic species richness and invertebrate and macroalgal densities. To conclude, our experiment demonstrates that Z. marina defines the patterns of benthic macroalgae and invertebrates but has moderate effects on sediment structure and metabolism in the Northern Baltic Sea. 相似文献
28.
Ahmad K Hegazy 《Journal of Arid Environments》1998,40(4):417-429
This study was conducted on a naturally growing population in Al-Khor mangrove swamps in Qatar during the years 1993–1995.Avicennia marinais the only mangrove species growing in Qatar and the Arabian Gulf region. The survivorship curve showed that early reproductive stages, starting from flower buds to seedlings, are at-risk relative to juvenile and adult individuals. The survival of adult plants is age-dependent. The phenological cycle indicated that the reproductive period extends from April to October, while vegetative activity occurs throughout the year with minimum growth during late autumn and early winter. Productivity estimated from litter fall showed considerable differences between seasons. Litter fall is bimodal, with the first peak prior to the start of the reproductive cycle and the second peak before the end of summer or early autumn. Total litter fall decreased from a maximum of 188 g m−2month−1to a minimum of 80 g m−2month−1. Litter decomposition was lower in winter than in the summer months. Calorific content of the decomposing litter was consistent with over 90% of litter energy lost over a 1-year period. The calorific content of buried leaves decreased from 6.0585 kcal g−1dry weight to 0.0532 kcal g−1dry weight after 1 year. Major human impacts on mangrove ecosystems in the region include oil pollution, solid and liquid waste disposal, coastal development, marine dredging, recreation activities, overgrazing, wood harvest, diversion of fresh water runoff and pest control. 相似文献
29.