涠洲岛珊瑚礁健康评估

【目的】科学地判断涠洲岛珊瑚礁的现状,并找出造成目前现状的主要原因,为及时采取有效措施以维持涠洲岛珊瑚礁的健康提供有力依据。【方法】根据历年来有关涠洲岛珊瑚礁生长、演变、环境变化与社会发展的研究成果和最新的调查研究资料,采用HRHPI的指标体系法,从生态结构、生态功能、压力及社会经济等几个特征属性对珊瑚礁健康进行评估。【结果】涠洲岛的自然环境仍适合石珊瑚的生存,石珊瑚的种类丰度仍正常;珊瑚礁的覆盖率降低、分布范围缩小、生物多样性下降,尤其在浅海和局部人为影响大的区域,珊瑚死亡率大于补充率。【结论】涠洲岛的珊瑚礁处于衰退中的亚健康状态。过度捕捞、污染、物理损伤（踩踏、抛锚、水下工程等）和大尺度环境变化（如气候异常）等是造成涠洲岛珊瑚礁衰退的主要原因。     

涠洲岛西局部造礁石珊瑚盖度和大小频率分布

本研究通过分析珊瑚大小频率分布,探讨涠洲岛西局部造礁石珊瑚群落结构特点和种群动态,以了解珊瑚的生活史和所经历的变化。所分析的珊瑚大小数据来自2021年2月24-26日开展的涠洲岛西珊瑚礁的造礁石珊瑚样带调查,利用对数转换将珊瑚大小变换为珊瑚迭代,然后作直方图对珊瑚大小频率分布加以分析。分析结果表明,片状的牡丹珊瑚属Pavona和块状的滨珊瑚属Porites、角蜂巢珊瑚属Favites、盘星珊瑚属Dipsastraea等在涠洲岛西局部珊瑚群落中占优势(珊瑚面积和珊瑚个数)。对数转换的大小频率分布呈正态分布,偏斜不明显,变异系数小于0.5,表明这些珊瑚目前处于正常的自然补充、生长和死亡过程。涠洲岛西局部造礁石珊瑚盖度降低,主要是因为个体大的枝状珊瑚锐减。     

涠洲岛园艺式珊瑚苗圃的架设与移植

【目的】探讨涠洲岛不同底质下最适宜的硬珊瑚苗圃架设方法和最佳移植培育种类。【方法】在涠洲岛周边海域砂质、基岩、珊瑚碎屑和礁石等4种不同底质架设固定式(20个)及悬浮式(112个)珊瑚苗圃,移植块状、枝状、叶状等7种硬珊瑚断枝,共2 436个;观测记录苗圃保存情况及珊瑚成活率、珊瑚体积增长率等。【结果】礁石底质海域的苗圃保存程度最高,为70%;其次是珊瑚碎屑海域(北部牛角坑)的苗圃,为57%。铁架式苗圃的平均保存率为63%,是保存程度最好的苗圃形式。经过一年时间的培育,风信子鹿角珊瑚Acropora hyacinthus的成活率为20%~80%,体积增加3.5倍;粗野鹿角珊瑚Acropora humilis成活率为25%~49%,体积增加1.5倍。其他种类珊瑚生长较慢,成活率较低。【结论】铁架式苗圃结构稳固、不易受台风等风暴潮的影响,是涠洲岛最适合的珊瑚苗圃形式。涠洲岛四面环海,珊瑚苗圃应架设在岛屿北部礁石和珊瑚碎屑基底的海域。风信子鹿角珊瑚在一年时间内体积可以增加3倍,且存活率高,是涠洲岛珊瑚礁移植最优先考虑的种类。     

Coral reef ecosystems in the South China Sea as a source of atmospheric CO<Subscript>2</Subscript> in summer

Field measurements of air-sea CO2 exchange in three coral reef areas of the South China Sea (i.e. the Yongshu Reef atoll of the Nansha Islands, southern South China Sea (SCS); Yongxing Island of Xisha Islands, north-central SCS; and Luhuitou Fringing Reef in Sanya of Hainan Island, northern SCS) during the summers of 2008 and 2009 revealed that both air and surface seawater partial pressures of CO2 (pCO2) showed regular diurnal cycles. Minimum values occurred in the evening and maximum values in the morning. Air pCO2 in each of the three study areas showed small diurnal variations, while large diurnal variations were ob-served in seawater pCO2. The diurnal variation amplitude of seawater pCO2 was ~70 μmol mol–1 at the Yongshu Reef lagoon, 420–619 μmol mol–1 on the Yongxing Island reef flat, and 264–579 μmol mol–1 on the reef flat of the Luhuitou Fringing Reef, and 324–492 μmol mol–1 in an adjacent area just outside of this fringing reef. With respect to spatial relations, there were large differences in air-sea CO2 flux across the South China Sea (e.g. ~0.4 mmol CO2 m–2 d–1 at Yongshu Reef, ~4.7 mmol CO2 m–2 d–1 at Yongxing Island, and ~9.8 mmol CO2 m–2 d–1 at Luhuitou Fringing Reef). However, these positive values suggest that coral reef ecosystems of the SCS may be a net source of CO2 to the atmosphere. Additional analyses indicated that diurnal variations of surface seawater pCO2 in the shallow water reef flat are controlled mainly by biological metabolic processes, while those of deeper water lagoons and outer reef areas are regulated by both biological metabolism and hydrodynamic factors. Unlike the open ocean, inorganic metabolism plays a significant role in influencing seawater pCO2 variations in coral reef ecosystems.     

涠洲岛珊瑚健康及其影响因子分析

根据2007年秋至2008年春间,涠洲岛6条主剖面15条断面的珊瑚和底质覆盖率、珊瑚补充量、死亡指数的一次两阶段的调查数据和同期4个季度月的水环境调查数据,结合以往的研究成果,初步分析了涠洲岛珊瑚健康状况及其影响因子。结果表明,调查断面珊瑚死亡指数平均为40.90%,珊瑚死亡发生于本次调查的两年前;珊瑚有恢复的迹象,但珊瑚补充量小,珊瑚补充量与活珊瑚+死珊瑚覆盖率显著相关(r=0.520,P<0.05);除汞、铅、锌和油类外,涠洲岛珊瑚礁海区水体的理化、生物因子符合一类海水水质标准,大体上呈微营养水平,春季的水体营养指数明显高于其他季节。涠洲岛珊瑚死亡率高和恢复慢,表明珊瑚处于退化中的亚健康状态。     

On biogeomorphology of Luhuitou fringing reef of Sanya City, Hainan Island, China

Based on comprehensive survey of 6 transects on Luhuitou fringing reef in Sanya City of Hainan Island, China, some features of its biogeomorphologic processes were found, including ( i ) three basic biogeomorphologic units: inner reef flat, outer reef flat and reef slope; (ii) two important biogeomorphologic boundary lines: up limit for live flat coral growing between inner and outer reef flats is Mean Lower Low Water of tropic tide ± 15 cm; the break in slope between reef flat and reef slope is Theoretical Lowest Tide±15 cm; (iii) three types of reef flat profiles in response to distinctive Holocene sea level changes and dynamic condition: Luhuitou type responds to falling sea level and low wave energy; Xiaodonghai type to falling sea sevel and high wave energy; type for atolls of Nansha Islands to stable sea level and low wave energy; (iv) hermatypic coral community is the most essential member in coral reef ecosystem and plays the most important role in biogeomorphologic process. Over the past 30 years Luhuitou fringing reef was severely destroyed by human activities, its biogeomorphologic function severely weakened, and it needs urgent management and protection.     

涠洲岛珊瑚礁特点、演变及保护与修复对策的思考

涠洲岛珊瑚礁最早形成于约7 000年前的末次海侵,是中国大陆沿海成礁珊瑚分布最北缘的典型边缘珊瑚礁(Marginal Coral Reefs),与区域内其他珊瑚礁缺少生态关联,其特征不同于热带珊瑚礁,即块状珊瑚占优势。20多年来,涠洲岛珊瑚礁持续退化,枝状珊瑚大量死亡,石珊瑚盖度急剧降低,反映珊瑚礁良好状况的指标生物如鹦嘴鱼、蝴蝶鱼等的数量大幅减少。近10年来,珊瑚虽未出现异常死亡现象,但珊瑚自然修复不明显,表明珊瑚补充不足。功能性植食性鱼类的缺乏,显示珊瑚礁恢复力不足。涠洲岛珊瑚礁国家级海洋公园的建立,体现了保护涠洲岛珊瑚礁的政治意愿。只有恢复鹦嘴鱼等功能性植食性鱼类的数量,才能恢复和增强珊瑚礁固有恢复力,进而促进涠洲岛珊瑚礁的自然恢复。人为修复可采取移植珊瑚断枝的方式,并以实现生态、经济和社会增益为目标,构建能应对人为干预且能持续演化的珊瑚礁。     

Status monitoring and health assessment of Luhuitou fringing reef of Sanya, Hainan, China

The monitoring survey and health assessment for benthic community were carded out in Luhuitou fdnging reef of Sanya, Hainan, China in 2002. Monitoring survey included manta tow, line intercept transect, video transect and digital photograph. The mean live coral cover was 23.40%. Comparison of used monitoring methods showed that video transect can replace line intercept transect, and 50 m transect is better than 20 m transect in uneven coral region. Survey data and comparison with previous research work showed that Luhuitou fringing reef has been damaged severely and has a general declining trend with live coral cover from about 85% in the 1960s down to 20% in 2004, but it still has quite high biodiversity and therefore has special protection value. Main factors of Luhuitou fdnging reef declining were human activities including reef rock digging and curios collecting, destructive fishing, sediment and pollutant from coastal land, and recent marine aquaculture. Only strengthening integrated management can reach improvement and restoration of Luhuitou declining coral reef ecosystem.     

Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South China Sea

Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the world.The characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental conditions.We documented a mass coral bleaching event in June 2007 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China Sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 35 species of corals (between 0-20 m in depth) were bleached.These bleached corals accounted for 15.6% of total corals in the investigated quadrats.The branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high SSTs.Surprisingly,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal stresses.The bleached corals had lost 72%-90% of their symbiotic zooxanthellae.Furthermore,corals that had no visual signs of bleaching had also lost 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of bleaching.The monthly mean SST during June 2007 was 30.8°C,the highest since 1998.Based on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching event.Our results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.     

中街山列岛岛礁生境游泳动物群落多样性及稳定性分析

基于2012年11月(秋季),2013年2月(冬季),2012年5月(春季),2013年8月(夏季)对中街山列岛海洋保护区岛礁区的定置刺网调查数据,对岛礁生境游泳动物群落多样性及群落稳定性分析,结果如下:岛礁区共出现鱼类40种隶属10目27科35属,甲壳类14种隶属2目9科10属,头足类1种。对群落多样性指数的分析结果显示,Margalef种类丰富度指数,Shannon-Wiener多样性指数,均为夏季秋季春季冬季,其均值分别为5.87、2.57;Pielou均匀度指数各季节相差不大,平均值为0.8。ABC曲线的分析显示:群落受干扰程度为秋季夏季春季冬季。群落的季节更替指数和迁移指数研究表明,AI值在冬季最高达221,在夏季最低为111。     

珊瑚礁相关病毒的研究进展

珊瑚礁被称为海洋中的“热带雨林”,是海洋生态系统中的核心组成部分之一。珊瑚礁病毒包含珊瑚本身感染的病毒和珊瑚共生生物（如藻类、细菌等）感染的病毒,对于珊瑚礁健康与疾病、生长与死亡起着独特而重要的作用,在维持珊瑚礁生态系统的物质循环和能量流动等生态学功能方面起着潜在作用。由于技术的局限以及关注度较低等原因,有关珊瑚礁病毒的研究较少。近年来,随着高通量测序技术的发展,宏转录组和宏基因组逐渐成为研究珊瑚礁病毒多样性及其生态学功能的重要方法之一。本文对国内外相关研究进行总结和归纳,拟为珊瑚礁病毒后续研究提供新的方向和思路,同时指导我国珊瑚礁的保护以及修复。     

北部湾涠洲岛珊瑚礁的研究现状及展望

综述涠洲岛珊瑚礁生态环境条件、珊瑚礁分布与优势种组成、珊瑚礁地貌与沉积以及珊瑚礁区浮游生物等方面的研究进展,提出今后对涠洲岛珊瑚礁的研究应重点围绕珊瑚礁生态学、珊瑚礁记录的古环境以及珊瑚礁资源开发与保护等方面进行。     

Estimate of carbonate production by scleractinian corals at Luhuitou fringing reef, Sanya, China

Carbonate production by scleractinian corals not only maintains coral reef growth, but also represents an important source of atmospheric carbon dioxide. In this paper the carbonate production by scler-actinian corals at Luhuitou fringing reef, Sanya, Hainan Island, China, is investigated with an ecological census-based method. Averaged carbonate production is 1.16 ± 0.55 kg·m-2·a-1 and 3.52 ± 1.32 kg·m-2·a-1 on the reef flat and reef slope, respectively, depending on the composition and distribution of cor...     

Coral community changes in response to a high sedimentation event: A case study in southern Hainan Island

A high sedimentation event caused by dredging and dumping of sediment was recorded on Xiaodonghai Reef in Yulin Bay,southern Hainan Island,China.Significantly high sedimentation and constant light shading were observed during the sediment dumping event(SD Event).Using long-term video transects,we quantified coral community changes and responses to the SD Event between 2008 and 2010.The SD Event caused severe coral mortality on Xiaodonghai Reef at a depth of 6 m,while corals at 3 m were less affected.Total live coral cover at 6 m decreased from 54.3% to 14.8%,and Diploastrea heliopora replaced Galaxea fascicularis as the dominant coral species at 6 and 9 m.The density of juvenile corals also declined after the SD Event,especially for the genera Galaxea and Platygyra.However,the density of juvenile Porites and Pocillopora spp.slightly increased.Monitoring for 11 months after the SD Event indicated no recovery of coral communities on Xiaodonghai Reef.Long-term video transect data also revealed that mean live coral cover dramatically declined,from 30.5% in 2008 to 9% in 2010,while the dominant corals in Yulin Bay shifted to more tolerant coral species,such as massive Porites spp.and D.heliopora.The rapid coral community degradation in Yulin Bay between 2008 and 2010 was probably caused by high sediment deposition resulting from intensive dredging and land-clearing activities.These results highlight the necessity for an integrated watershed management to control sediment deposition on near-shore coral reefs.     

Effects of temperature,hypoxia, ammonia and nitrate on the bleaching among three coral species

Coral bleaching, which is defined as the loss of colour in corals due to the loss of their symbiotic algae (commonly called zooxanthellae) or pigments or both, is occurring globally at increasing rates, and its harm becomes more and more serious during these two decades. The significance of these bleaching events to the health of coral reef ecosystems is extreme, as bleached corals exhibited high mortality, reduced fecundity and productivity and increased susceptibility to diseases. This decreased coral fitness is easily to lead to reef degradation and ultimately to the breakdown of the coral reef ecosystems. Recently, the reasons leading to coral bleaching are thought to be as follows: too high or too low temperature, excess ultraviolet exposure, heavy metal pollution, cyanide poison and seasonal cycle. To date there has been little knowledge of whether mariculture can result in coral bleaching and which substance has the worst effect on corals. And no research was conducted on the effect of hypoxia on corals. To address these questions, effects of tem- perature, hypoxia, ammonia and nitrate on bleaching of three coral species were studied through examination of morphology and the measurement of the number of symbiotic algae of three coral species Acropora nobilis, Palythoa sp. and Alveopora verrilliana. Results showed that increase in temperature and decrease in dissolved oxygen could lead to increasing number of symbiotic algae and more serious bleaching. In addition, the concentration of 0.001 mmol/L ammonia or nitrate could increase significantly the expulsion of the symbiotic algae of the three coral species. Except for Acropora nobilis, the numbers of symbiotic algae of other two corals did not significantly increase with the increasing concentration of ammonia and nitrate. Furthermore, different hosts have different stress susceptibilities on coral bleaching.     

数字全景钻孔摄像系统在西沙琛航岛地质调查中的应用

在西沙琛航岛的地质调查中,数字全景钻孔摄像系统被应用到CK1孔和CK2孔的勘测中,获得了大量珊瑚礁地质的第一手资料,它不仅指导了现场的钻探工作,而且在后期的分析研究中,钻孔图像能够反映珊瑚礁的孔壁特征,并能够根据孔壁特征划分珊瑚礁的特殊区域,在与其他资料的对比中,发现勘测结果基本保持一致.从中可以得出的结论为:数字全景钻孔摄像系统在岛礁钻探过程中能够发挥重要作用;数字全景钻孔摄像系统能够准确有效地勘测出珊瑚礁的钻孔内地质特征;数字全景钻孔摄像系统能够划分珊瑚礁地层的特殊区域.     

我国人工养殖造礁石珊瑚的未来主要应用

论述了国外人工养殖珊瑚的发展和兴起以及我国对石珊瑚养殖技术的研究,同时还论述了人工养殖珊瑚的未来应用.     

中国南海软珊瑚Cladiella densa的化学成分研究

本文报道从软珊瑚Ｃｌａｄｉｅｌｌａｄｅｎｓａ中分离出正三十一碳醇，鲨肝醇和柳珊瑚甾醇３个化合物，正三十一碳醇是在软珊瑚中首次发现。     

广东石门台自然保护区常绿阔叶林物种多样性分析

基于样方调查的基础上,研究了石门台自然保护区内木荷+紫花杜鹃林、木荷+腺叶山矾林和木荷林3种常绿阔叶林物种的多样性.研究结果表明:1)石门台自然保护区物种十分丰富,3个群落冠层树种共计41科74属105种,其中木荷+紫花杜鹃林34科53属66种,木荷+腺叶山矾林28科44属56种,木荷林24科39属50种.2)保护区内3个样地群落共计75个样方,其中丰富度、均匀度指数、Shannon-Wiener多样性指数和Simpson指数的平均值分别为12.466,0.731,1.807和0.726.总的来说,石门台自然保护区常绿阔叶林物种多样性指数、均匀度指数和Simpson指数都比较高.     

山西天龙山植物群落物种多样性研究

应用丰富度指数、均匀度指数、多样性指数对山西天龙山植物群落物种多样性进行了研究．结果表明：天龙山植物群落的物种多样性指数与海拔高度有较密切的关系，随着海拔的升高，植物群落的丰富度指数呈上升趋势，均匀度指数呈平缓下降的趋势，多样性指数变化趋势不明显；天龙山植物群落的物种多样性指数和丰富度指数明显受群落类型和群落结构的影响，群落结构越复杂，丰富度指数和物种多样性指数越大，均匀度指数越小．