潮滩冲淤扰动下外来与乡土红树植物幼苗稳定性差异

引种外来树种是我国各地在红树林修复实践中常用的措施。由于更容易在困难立林地存活, 外来树种被认为更具竞争优势。为弄清外来与乡土红树植物物种在困难立林地存活能力的差异及其原因, 本研究选取典型外来引种先锋树种拉关木(Laguncularia racemosa)与乡土先锋植物白骨壤(Avicennia marina)为研究对象, 通过控制实验探究潮滩冲淤扰动条件下幼苗稳定性差异及其形成机制。结果表明, 幼苗抗侵蚀能力与幼苗根冠比显著正相关, 泥沙淤积抑制幼苗根系生长, 而底床侵蚀则促进根系伸长。与白骨壤相比, 拉关木幼苗的主根更长, 根冠长度比更大, 更能抵抗底泥的侵蚀扰动, 且通过根系伸长以增强幼苗稳定性的能力也更强。拉关木幼苗比白骨壤更能适应潮滩冲淤扰动, 其竞争优势从幼苗阶段就已经建立。本研究结果可为红树林修复实践中树种和宜林地的选择提供参考, 亦可为评估外来红树物种入侵风险评价提供依据。     

厦门东屿白骨壤林土壤甲烷的产生量、氧化量、传输率与库量

测定了厦门东屿白骨壤（Avicennia marina）林土壤的甲烷产生量及其在土壤中的氧化、传输与库量．土壤甲烷产生量基本上呈内滩>中滩>外滩的滩面变化趋势，季节变化趋势为秋、冬季低于春、夏季，与甲烷氧化量的时空变化模式一致，与甲烷库量的时空变化模式也基本相同．所有季节所有滩面土壤甲烷产生量、氧化量、库量的平均值分别为9.11mg/(m     

盐胁迫下红树植物蛋白质的比较分析

采集白骨壤的种子分别置于盐度为0的自来水和盐度为50的海水中沙培 ,从叶片中抽提总蛋白质 ,同时进行双向电泳。比较发现3个蛋白质点SR1、SR2、SR3只在盐度为50的海水培养下稳定地出现 ,另1个蛋白质点SR4只在无盐条件下出现。初步认为这4种蛋白质与白骨壤的耐盐性相关。     

两种不同生境的白骨壤种群的遗传结构

本文研究了广西沙质土壤和淤泥质土壤白骨壤种群的遗传多样性和遗传分化。结果表明，不同生境的白骨壤种群维持着较高的遗传多样性，观察杂合度为0．350，预期杂合度为0．259。不同生境的白骨壤种群的遗传分化很低，种群间的遗传分化为FST＝0．062 ，表明总的遗传变异中有93．8％来自种群内。基因流顺畅，Nm=3.78。种群间的遗传一致度和遗传距离分别为0．955和0．046。     

Geomorphic knowledge for mangrove restoration: a pan‐tropical categorization

Extreme events such as storm surges and tsunamis in combination with subsidence of densely populated coastal areas pose an increasing threat to millions of people in the tropics. Intertidal mangrove forests may form a natural protection against some extreme events, but have also widely been destroyed by coastal development. The establishment of mangroves and the maintenance of their stability over the short‐ to long‐term requires an understanding of sedimentary processes and landforms in the coastal zone, making geomorphology a crucial, but sometimes neglected discipline when attempting restoration for disaster risk reduction. Mangrove geomorphic setting varies markedly across the tropics, depending on abiotic parameters such as suspended sediment supply and tidal range, with different restoration strategies suitable for each. In this study we provide a global categorization of mangrove geomorphic settings, based on the literature and global remote sensing data. The world's mangroves can be broadly defined as: (1) minerogenic and high tidal range; (2) minerogenic and low tidal range; and (3) organogenic and low tidal range. We further discuss restoration and management approaches most suitable for each geomorphic setting. Overall, this study can be used to inform managers about the relevance of geomorphic knowledge for successful mangrove restoration, how an understanding of geomorphology can influence site selection and restoration success, and how to match specific restoration methods to the prevailing geomorphic context. The stronger incorporation of geomorphic knowledge into site planning and design will improve the success rates of restoration for this important and globally threatened ecosystem. Copyright © 2015 John Wiley & Sons, Ltd.     

Chlorophyll-deficient propagules of Avicennia marina and apparent longer term deterioration of mangrove fitness in oil-polluted sediments

A correlation between petroleum hydrocarbon concentrations in sediments and chlorophyll-deficient mutations in mangroves may occur also in Australian mangroves. Earlier reports of such mutations in the Caribbean area were evident in viviparous propagules of the common mangrove genera, Rhizophora, borne on otherwise normal trees. These mutant propagules were termed albinos' since they lacked chlorophyll and normal green coloration, leaving them white, yellow or red. The mutation was considered lethal since newly established albino seedlings appeared unable to survive more than a few months. Our preliminary investigation of mangroves in SE Queensland found a similar mutation in another common mangrove genus, Avicennia, and this was apparently also correlated with oil concentrations in sediments. Although, more evidence is required, an apparently similar relationship shows that whatever caused the mutations may act commonly across a diverse range of plant types in quite separate locations. How widespread might this mutation be in mangroves? How many genera and species are affected? Are all occurrences correlated with oil in sediments? Does oil cause the mutation? We discuss these important questions and the potentially serious implications to coastal management where high mutant densities may be indicative of longer term genetic deterioration of mangrove habitat in oil-polluted wetland environments.     

Genetic variation in Avicennia marina in three estuaries of Sydney (Australia) and implications for rehabilitation and management

In order to ensure conservation of mangroves, genetic diversity in remaining populations must be explored. Both morphological and isozyme analyses were used and compared in investigating the intra- and inter-estuarine variation in Avicennia marina in Sydney, the most urbanised area in Australia. Sediment characteristics, metal levels, tree attributes, leaf morphology and isozyme/allozyme analyses were conducted. Tree characteristics did not prove to be adequate genetic markers, but leaf morphology may be of use in this species. Isozyme/allozyme analyses indicated that genetic distance corresponded with geographic distance, although habitat metal levels may indicate local selection pressures. High levels of heterozygote deficiencies were displayed in each estuary, which could threaten future viability. The results hold implications for management as periodic isozyme analysis may be useful in indicating management needs. The identification of metal-tolerant types may also be useful. Transplantation among estuaries may assist in increasing genetic diversity, if considered desirable. Whatever the management aims, isozyme/allozyme analyses are shown to be useful for revealing genetic diversity in this species.     

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

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。     

Perspectives on survival, phenology, litter fall and decomposition, and caloric content ofAvicennia marinain the Arabian Gulf region

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.