Absorption Efficiencies of the Intertidal Mangrove Dwelling Mollusk Melampus coffeus LINNÉ and the Rocky Intertidal Mollusk Acanthopleura granulata GMELIN     

David  Mook. 《Marine Ecology》1986,7(2):105-113

Abstract. .The absorption efficiencies of the intertidal mangrove dwelling mollusk Melampus coffeus and the rocky intertidal dwelling mollusk Acanthopleura granulata were calculated by a modification of CONOVER'S (1966) equation. M. coffeus tended to consume fresh mangrove leaves indicating that M. coffeus may obtain much of its energy from the actual substrate material rather than from associated bacteria and meiofauna on decaying leaves. Obtaining energy directly from the substrate may be a mechanism for M. coffeus to utilize its food source more efficiently. In contrast, chitons (A. granulata) may utilize the higher energy components of their limited intertidal microflora! food source. Using the high energy component of a food source may be an additional mechanism by which organisms efficiently utilize a food source.  相似文献   

Nocturnal fish utilization of a subtropical mangrove‐seagrass ecotone     

Neil Hammerschlag  Joseph E. Serafy 《Marine Ecology》2010,31(2):364-374

Whereas diel fish migration between mangrove and seagrass habitats has been recognized for decades, quantitative studies have focused mainly on diurnal patterns of fish distribution and abundance. In general, previous studies have shown that fish abundances decline with increasing distance from mangroves; however, evidence for such a pattern at night, when many fishes are actively feeding, is scarce. The present study is the first to report nocturnal fish abundances along a continuous distance gradient from mangroves across adjacent seagrass habitat (0–120 m). Here, we used nocturnal seine sampling to test the null hypothesis (based on diurnal studies and limited nocturnal work) that fish abundance would decrease with increasing distance from shoreline. We focused on species and life‐stage‐specific abundance patterns of Lutjanus griseus, Sphyraena barracuda, Archosargus rhomboidalis, and Haemulon sciurus. Results indicated that assemblage composition and structure differed significantly by season, likely influenced by temperature. However, within each season, the fish habitat use pattern at both the assemblage and species‐specific level generally failed to support our working null hypothesis. Species‐specific analyses revealed that, for most species and life‐stages examined, nocturnal abundance either did not change with distance or increased with distance from the mangrove‐seagrass ecotone. Our results suggest that analyses where taxa are grouped to report overall patterns may have the potential to overlook significant species‐ and stage‐specific variation. For fishes known to make nocturnal migrations, we recommend nocturnal sampling to determine habitat utilization patterns, especially when inferring nursery value of multiple habitats or when estimating fish production.  相似文献   

广西钦州湾红树林抗菌活性菌株Erwinia sp. 5-8的筛选及发酵条件的优化          下载免费PDF全文

孟令洋  姜伟  张培玉  林学政 《海洋科学进展》2015,33(2):270-278

以金黄色葡萄球菌为指示菌,采用琼脂扩散法从国家海洋局海洋生物活性物质重点实验室广西钦州湾红树林微生物资源库中筛选获得一株具有明显抑菌效果的菌株5-8,对该菌株进行了分子鉴定与系统发育分析。结果表明,此菌为欧文氏菌属(Erwinia)。通过单因子试验对其发酵条件进行了优化,优化后发酵条件为:最佳氮源为蛋白胨,最佳碳源为葡萄糖,发酵培养基初始pH值为8.0,发酵温度为25℃,盐度为1.5,摇瓶装液量30%,接种量为1%(V种子液∶V培养液=1∶100)。  相似文献   

泉州湾洛阳江河口桐花树和秋茄红树植物中重金属元素的分布与富集特征   总被引：2，自引：0，他引：2  

胡恭任  于瑞莲  赵金秀  刘小进  涂湘林 《岩矿测试》2010,29(3):236-240

通过测定泉州湾洛阳江河口红树林区表层沉积物中酸提重金属元素含量及桐花树、秋茄两种红树植物各部位中重金属元素含量,分析了重金属元素在两红树植物不同部位的分布特征及其富集和迁移能力,并初步探讨了两种红树植物体内各重金属元素的主要来源。红树林区各采样点表层沉积物中重金属元素酸提量顺序为:FeMnZnPbCuCrN iCo,Cu和Pb的平均酸提量超过第一类海洋沉积物质量标准限值。同种元素在两种红树植物不同部位中的含量顺序一致:Cu为根枝叶;N i为叶根枝;Fe、Mn、Cr、Zn、Pb、Co为根叶枝。两种红树植物对N i、Cr、Cu、Zn、Fe、Mn的富集能力高于Co和Pb。秋茄对Cu、N i、Mn、Fe、Co的富集能力比桐花树略强些,而对Zn、Cr、Pb的富集能力则相对弱些;但两种植物对各元素的富集能力都达不到超富集植物的要求。两种植物对N i元素的富集能力都大于其他元素,且都集中在叶部,其他元素则主要集中在根部。除N i外,其余元素在两植物体内的迁移系数均小于1。桐花树中的Cr和秋茄中的Cu、Zn、Mn主要来源于林地沉积物,其他元素在两植物各部位均有不同的来源。  相似文献   

Recognising subtidal foraminiferal assemblages: implications for quantitative sea‐level reconstructions using a foraminifera‐based transfer function     

Sarah A. Woodroffe 《第四纪科学杂志》2009,24(3):215-223

Microfossil‐based transfer function models are increasingly used to provide decimeter‐scale sea‐level change reconstructions. In this paper I demonstrate that in the tropical location of northern Australia problems arise in selecting the appropriate elevation range for the modern training set used to calibrate fossil calcareous foraminiferal assemblages. Most calcareous foraminiferal species found in cores occur in both modern intertidal and shallow subtidal environments. A lack of independent measures to indicate whether fossil assemblages come from intertidal environments forces use of a training set that includes intertidal and subtidal environments. This results in decreased precision compared to using a training set solely from intertidal environments. The widely used method of assessing model fit to fossil assemblages (modern analogue technique) often fails to discriminate between acceptable and unacceptable reconstructions. It is important to investigate a number of different measures including modern analogue technique, canonical correspondence analysis and changing bootstrapped sample specific transfer function errors to fully understand the level of similarity between modern and fossil foraminiferal samples, to judge the reliability of transfer function‐predicted sea‐level reconstructions. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

Litterfall dynamics and nutrient decomposition of arid mangroves in the Gulf of California: Their role sustaining ecosystem heterotrophy     

R. Sánchez-Andrés  S. Sánchez-Carrillo  L.C. Alatorre  S. Cirujano  M. Álvarez-Cobelas 《Estuarine, Coastal and Shelf Science》2010

This study shows results on litterfall dynamics and decay in mangrove stands of Avicennia germinans distributed along a latitudinal gradient (three forest sites) in the Gulf of California, in order to assess whether internal sources could support the observed mangrove ecosystem organic deficit in this arid tropic. Total mean annual litterfall production increased southward (712.6 ± 53.3, 1501.3 ± 145.1 and 1506.2 ± 280.5 g DW m⁻² y⁻¹, in the Yaqui, Mayo and Fuerte areas respectively), leaves being the main component of litter in all locations during the entire year, followed by fruits. The wet season (June–September) showed the highest litterfall rates through fruits. The temporal trend of litterfall production was significantly explained through mean air temperature (R² = 68%) whilst total annual litter production in the entire region showed a statistically significant relationship with total soil phosphorus, salinity, total nitrogen, organic matter and tree height (R² = 0.67). Throughout 117 days of the decomposition experiment, the litter lost 50% of its original dry weight in 5.8 days (average decay rate of 0.032 ± 0.04 g DW d⁻¹) and there were not significant differences in the remaining mass after 6 days. The percentage of both C and P released from the litter correlated significantly with the ratio of tidal inundated days to total experiment days (R² = 0.62, p = 0.03 and R² = 0.67, p = 0.02, respectively); however, the frequency of tidal inundation only showed a significant increase in C release from Avicennia litter after 6 and above 48 days of decomposition. Whereas the total C content of litter bags decreased linearly over the decomposition to (% Total C = 5.52 − 0.46 days, R² = 0.81, p = 0.0005), N content displayed an irregular pattern with a significant increase of decay between 48 and 76 days from the beginning of the experiment. The pattern for relative P content of litter revealed reductions of up to 99% of the original (%tot-P = −9.77 to 1.004 days, R² = 0.72, p = 0.01) although most of the P reduction occurred between 17 and 34 days after the experiment started. Soil N and P contents, which exhibited significant differences in the course of the decomposition experiment, appeared to show significant differences between sampling sites, although they were not related to tidal influence, nor by leaf and nutrient leaching. In a global basis, C/N litter ratios decreased linearly (C/N = 32.86 − 0.1006 days, R² = 0.62, p = 0.02), showing a strong and significant correlation with meteorological variables (R² = 0.99, p = 0.01). C/P ratios of litter increased through an exponential function (C/P = 119.35e^0.04day, R² = 0.89, p < 0.001). Changes in the remaining percentage of litter mass during the experiment were significantly correlated with soil C/N ratio (R² = 0.56, p = 0.03) as well as with the soil C/P ratio (R² = 0.98, p < 0.001). Our results of litter decomposition dynamics in this mangrove support the fact of null net primary productivity of the arid mangrove wetlands: fast litter decomposition compensates the ecosystem organic deficit in order to sustain the mangrove productivity. Litter decomposition plays a key role in the ecosystem metabolism in mangroves of arid tropics.  相似文献   

我国红树林湿地研究进展   总被引：15，自引：3，他引：15  

黄初龙  郑伟民 《湿地科学》2004,2(4):303-308

红树林湿地是分布于亚热带、热带滨海地区的典型湿地，具有其它湿地类型所不具备的特殊的演化过程，形成独特的水文、土壤和植被特征。由于人类活动的影响，近年来，我国红树林湿地出现了面积锐减、生态系统结构简化、生物多样性降低、生态功能退化等严重问题，使红树林湿地的可持续利用面临严重挑战。从湿地生态、湿地功能及湿地开发利用、保护与管理等方面评述我国红树林湿地生态系统的研究现状，探讨我国红树林湿地未来研究的主要科学问题，进而明确红树林湿地可持续利用研究的方向和途径。  相似文献   

Preliminary studies on methane fluxes in Hainan mangrove communities     

卢昌义  黄玉山  谭凤仪  叶勇  崔胜辉  林鹏 《中国海洋湖沼学报》1998,16(1):64-71

INTRODUCTIONChrbondioxideandInehanearethetwomostabundantabosphericcarbonspedes.Methane'sconcenhati0nintheboposphereinonsesO.7-l.l%peryearraasmussenandKhaili,l98l,BlakeandRowand,l988,Scheeetal.,l989).Ihauseofmethne'sforpaCtontheearth'sclirnateandthechernistryoftheatInosphere,thebudgetofabosphericmethanehasmivedconsiderableattchti0n.Wetlandsareestirnataltobeoneofthelamptsoimofabosphericmethane,aocountingforab0ut4O%to5O%0ftheglobalInehanesoonannually(Cforneand0reInland,l988,WhitingandC…  相似文献   

Vegetation analysis of a typical mangrove swamp—Lai Chi Wo coast of Hong Kong     

Lu Chang-yi  Wong Yuk-shan  F. Y. Tam Nora  Berry Richard 《中国海洋湖沼学报》1998,16(1):72-77

A vegetation analysis reveals that the Lai Chi Wo mangrove swamp in Hong Kong has 10 mangrove species comprising 76.9% of the total number of mangrove species in Hong Kong. This swamp is a mixed community dominated byAegiceras corniculatum, Heritiera littoralis, Excoecaria agallocha, Kandelia candel, Bruguiera gymnorrhiza, with importance values of 37.88, 28.19, 14.33, 11.33 and 8.27 respectively. The community’s mangrove species diversity and evenness, as based on the Shannon-Wiener Function, were 1.44 and 62.01%, which were lower than those of the south su-tropical evergreen broad-leaf forest community but its ecological dominance (0.26) was higher. The correlation information field (CIF) method, a useful analytical method for complex forest community, was adopted in the present mangrove analysis. The species correlation information was:Aegiceras corniculatum (0.268)>Heritiera littoralis (0.250)>Kandelia candel (0.220)>Excoecaria agallocha (0.169)>Bruguiera gymnorrhiza (0.101). The correlation information of the mangrove community was 1.008. This work was financially supported by the Agriculture and Fisheries Department of The Hong Kong Government and The Hong Kong University of Science & Technology.  相似文献   

中国热带红树林的发展及其地理背景   总被引：5，自引：0，他引：5  

黄镇国  张伟强 《地理学报》2002,57(2):174-184

参照约３０个红树林孢粉分析实例，探讨中国南方晚第三纪以来红树林的发展。红树林开始出现于晚始新世；晚第三纪其分布比今偏北；第四纪冰期使红树林向南退缩至雷州半岛北部。末次间冰期４２ ０００～２５ ０００ ａ ＢＰ红树林扩展，以海桑属为代表的典型红树林的北界从现今的 １９°３０′扩展到２３°４０′Ｎ。末次冰期红树林衰落。早全新世９ ６００～７ ９００ ａ ＢＰ红树林复兴，中全新世达到繁盛，向北分布到闽江口（２６°Ｎ），与现今的北界一致，但是中全新世以来海桑属在１９°３０′Ｎ以北不再出现，奠定了现今红树林地带性分布的格局。  相似文献