深圳湾引种红树植物海桑的幼苗发生和扩散格局的生态响应

海桑（Sonneratia caseolaris）是我国华南沿海主要红树林造林树种,在深圳湾引种造林15年后,在天然红树林和光滩中出现了大面积的扩散。为了研究深圳湾红树植物海桑的幼苗扩散及其与生态因子的关系,作者采用样线和样方调查法于2006年9月至2007年9月对深圳福田红树林内天然扩散的海桑幼苗的密度、高度和盖度及其相关生态因子（包括种间竞争、群落类型、光照、扩散距离与滩面高程）进行了6次调查。天然红树林和人工海桑林林下海桑幼苗密度在调查初期分别为24．7棵/m^2和19．7棵／m^2,到2007年9月林下的一年生海桑幼苗全部死亡,说明林下的弱光生境显著抑制了海桑幼苗的早期生长和自然更新。不同林型下（包括天然白骨壤林和秋茄林、人工海桑林）的海桑幼苗的密度、高度、盖度差异不显著（P〉0．05）;而林中空地各指标显著高于林下（P〈0．05）。虽然深圳福田红树林滩面高程介于1．12—2．10m（黄海平均海平面）之间,海桑幼苗自然扩散分布的最适滩面高程是1．40-1．60m,属于深圳湾红树林的中高潮滩,但幼苗密度与滩面高程之间相关性较小。海桑具有一定的长距离扩散能力,天然白骨壤林和秋茄林下海桑幼苗密度与其扩散距离（距最近母树的距离）之间呈显著负相关。天然白骨壤林和秋茄林下海桑幼苗密度与光照强度相关性不显著（P〉0．05）,而人工海桑林林下的海桑幼苗密度与光照强度呈显著正相关,且相关系数逐次增大,说明海桑幼苗的早期生长受到光照强度的影响极为显著。因此,深圳湾引种海桑的繁殖体在天然白骨壤林和秋茄林下的扩散主要受与母树距离的影响,但在海桑人工林下光照强度是影响幼苗分布的最重要生态因子。     

红树林宜林海洋环境指标研究

通过文献资料综合和实地调查,分析研究了温度、盐度、沉积物、潮汐浸淹和波浪能量5种海洋环境因素对红树林总体和各树种分布和生长的影响。明确指出了温度对红树林纬向分布、盐度对红树林沿河口湾和潮水河的上溯、潮汐浸淹频率对红树林沿潮滩的横向分布、和海岸波浪能量对红树林由港湾向开阔海岸的沿岸分布的主导控制作用和各自在我国东南沿海红树林区表现的临界参数。最冷月平均气温9.3℃和水温10.6℃,为最耐寒树种秋茄人工种植分布的北界;大片红树林可分布于河口湾和潮水河的全年大部分时间以咸水为主的岸段(如夏季盐度常＜2.0‰,冬季盐度可达15‰～20‰),零星红树植物可接近枯季大潮咸水上界;红树林只能占据平均海平面(或稍上)与回归潮平均高高潮位之间,大致为潮汐浸淹频率47.5%和2.9%;利用16个方位的平均风速V(m/s),风向频率F(%),有效风区长度L(km),计算海岸波能指数W=∑(Vi2FiLi),W＜7.0×103为适宜红树林生长的低波能海岸;W＞10.5×103为不适宜红树林生长的高波能海岸;W=（7.0～10.5）×103为红树林生长零星或很差,或仅能生长人工林或幼林的中波能海岸。这些临界参数可以作为上述海洋环境因素定量的总体的宜林指标。     

英罗港红树林昆虫群落及其多样性的研究

用１９９５～１９９６年在广西英罗港红树林区取样所得的资料探讨了英罗港红树林昆虫群落及其多样性特点。结果表明,英罗港红树林昆虫种类有１９５种;主要优势中为黑褐举腹蚊（Ｃｒｅｍａｔｏｇａｓｔｅｒ ｒｏｇｅｎｈｏｆｅｒｉ）、东京弓背蚁（Ｃａｍｐｏｎｏｔｕｓ ｔｏｋｉｏｅｎｓｉｓ）和三条螟蛾（Ｄｉｃｈｏｃｒｏｃｒｉｓ ｃｈｏｒｏｐｈａｎｔａ）;内滩昆虫群落多样性高于中滩、外滩。潮汐和风暴对昆虫群落多样性的     

不同海拔高程梯度下鄱阳湖典型草洲植物群落物种-多度分布格局的模型拟合

基于恒湖农场茶叶港草洲4个样带、19个样地（5 m×5 m）沿海拔高程（高高程-湖边、中高程-洲滩中间、低高程-洲滩边缘）调查得到的植被数据,用4种生态位模型拟合研究该区域不同海拔高程段植物种-多度分布格局。结果表明：（1）随着海拔高程下降,群落偶见种不断减少,且平均盖度均较低;常见种数目保持不变,其中优势种灰化薹草（Carex cinerascens Kukenth）平均盖度、平均高度持续升高,在群落中保持较高的优势地位;（2）3个高程段内生态位优先占领模型对群落物种-多度分布格局有较高的拟合优度（P < 0.05,AIC值分别为-149.41、-61.11、-25.63）,断棍模型、重叠生态位模型、优势优先模型总体上拟合效果较差（P < 0.05,但AIC值均较大）。为研究区植物群落生物多样性的保护和构建机制的探索提供了一定参考。     

澳门红树林植物组成及种群分布格局的研究

调查工作于１９９２年４月～１９９４年９月在路环及凼仔红树林区内进行．路环红树林面积约７．１１５ｈｍ２,凼仔红树林面积约５７．２０５ｈｍ２．在两地区的海滩中,红树林植物计有４科４种,分属于红树科（Ｒｈｉｚｏｐｈｏｒａｃｅａｅ）、紫金牛科（Ｍｙｒｏｉｎａｃｅａｅ）、马鞭草科（Ｖｅｒｂｅｎａｃｅａｅ）和爵床科（Ａｃａｎｔｈａｃｅａｅ）．海岸半红树植物计有１５科２７种．利用样带法研究澳门红树林种群的分布格局,除秋茄为随机分布外,桐花树、白骨壤及老鼠勒均趋于集群的分布格局．结合数据分析８个研究区域种群生态位序列,只有凼仔红树林研究区最具有显著的生态位序列．     

西门岛人工秋茄林恢复对大型底栖生物的影响

选择乐清湾西门岛海域相同高程断面不同造林时间的人工红树林(秋茄林)、光滩和互花米草丛,采用空间代替时间的方法,分析我国分布最北界人工红树林造林过程对大型底栖生物的影响.大型底栖动物生活型分布基本表现为幼林(1、4、8a秋茄林)以底上附着型为主,而在光滩、50a秋茄林和互花米草中底下生活类群相对增加.并且穴居型动物只出现在发育成熟的生态系统内.各项指标显示50a老林群落生态稳定性较好,光滩和互花米草丛次之,但优于发育中的秋茄幼林.与以往研究结果不同,50a老林的大型底栖动物生物种类的丰度及群落的物种多样性最高,并不与红树林的发育状况呈负相关,也不比邻近光滩低.结合50a林下滩涂底泥情况,西门岛50a红树林林下滩涂的底质发育要落后于国内天然红树林土壤.这可能与当地红树林造林规模小以及强潮差海域有关.此外,红树林恢复过程中,大型底栖动物生物多样性与生态稳定性之间的线性关系,其适用的系统面积和演替时间的尺度范围有必要做更加深入的探讨.     

木榄幼苗对淹水胁迫的生长和生理反应

在搭建于广西英罗湾红树林外裸滩的试验平台上设置8个海面高程组,研究全日潮海区潮汐淹水胁迫对木榄(Bruguiera gymnorrhiza)幼苗的生长和生理影响.幼苗立地基质平面的海面高程为320～390 cm,相邻高程组相差10 cm,幼苗培养时间为1 a.结果表明:小高程和大高程处理均促进木榄幼苗茎高度的增长,中等高程则起抑制作用;中等高程组幼苗茎节数稍少;叶数、叶面积与叶保存率均随淹水程度加大而急剧下降;小高程生境对叶片叶绿素含量的促进作用较微弱,而大高程生境更有利于叶绿素含量上升;但较长时间的淹水胁迫使叶绿素a/b比值反而较高;小高程处理均促使叶片和根系中超氧物歧化酶(SOD)和过氧化物酶(POD)酶活性增强,同一高程组的木榄幼苗根系中超氧物歧化酶和过氧化物酶酶活性均高于叶片的数倍;较大高程生境更有利于木榄幼苗生物量累积,尤其是叶生物量,同时随着淹水程度的加大,新生器官中生物量分配比例由叶向茎转移;所有高程组均有一些幼苗死亡,海面高程越小幼苗存活率越低,由73.6%下降到35.0%.综合考虑,建议北部湾海区木榄胚轴造林的宜林临界线高程不低于当地平均海面以上21 cm.     

人工红树林湿地系统净化污水研究进展

咸淡水交接处这种特殊的生境造就了红树植物“抗污”和“降污”的功能,但能否将自然红树林湿地作为污水处理场所目前仍有争议。按照构建的人工红树林湿地的类型,分为三大类：模拟潮汐湿地系统、人工红树林污水处理系统以及红树林种植-养殖生态耦合系统。第一类系统模拟了自然海滩上的潮涨潮落的情形,第二类系统与一般人工湿地相类似,而第三类系统是指在养殖塘种植红树植物以去除有机物和营养盐。不同的类型反映了该领域研究工作的不断深入,展现了红树林湿地净化污水从理论探索向实际应用不断靠近的过程。应用人工红树林湿地净化污水具有较大的可行性,前景可观。     

恢复初期红树林树栖滨螺科动物的组成与分布

滨螺科动物是红树林中常见的底栖动物,它们的形态、行为和分布等与红树林植被密切相关。本文调查了植被恢复初期(3年生)红树林树栖滨螺科动物的组成和分布情况,并探讨滩涂高程和树种对滨螺科动物分布的影响。结果表明:植被恢复初期滨螺科物种已成为优势类群,密度达到32.67 ind·m~(-2);黑口滨螺在不同滩涂高程下均为优势种,其密度和生物量在黄零1.8 m高程的秋茄林内较其他林地(黄零2.2和2.6 m)高;粗糙滨螺仅出现在黄零1.8 m的秋茄林内;种植于黄零1.6 m高程的桐花树林内黑口滨螺的生物量和密度均大于同样高程下的秋茄林,但桐花树林内的个体小于秋茄林内的个体;粗糙滨螺在不同树种间的分布没有明显差异;滨螺科物种的分布在红树林恢复初期随生境的异质性表现出差异,这种差异可能与植被形态导致的物理环境差异以及滨螺科物种活动习性、繁殖扩散模式等生物学特性有关。     

关注红树林

红树林是热带海岸潮间带的木本群落。由于温暖洋流的影响,有的可分布到亚热带,有的受潮汐影响,也可分布子河口海岸和水陆交迭的地方。因此,红树植物具有在每日浸润的潮间带生长的真红树植物和只有高洪潮方可浸润的高潮带以上的两栖性的半红树植物。红树植物只包括木本植物,一般都没有包括群落周围的统称为伴生植物的草本植物、藤本植物和附生植物。     

传统渔业活动对广西英罗港红树林区渔业资源的影响与管理对策

广西英罗港红树林区滩涂和光滩潮水中大型底栖动物和游泳动物曾很丰富。近4年来由于海鲜价格不断提高,林区的人为滥捕已使大型底栖动物和游泳动物的数量分别下降了约60%和80%。捕获方式有挖掘滩涂底栖动物,在红树林光滩潮水和林内潮沟进行网捕、炸鱼和毒鱼,网眼小至0.25 cm。传统的捕获萎缩了生态食物网的通量,破碎了生境,威胁着种群的繁衍。由于红树林区的渔业多少是当地群众的生计,完全封闭滩涂进行保育目前不可能。为此建议对英罗港红树林区滩涂施行封滩轮育,同时加强公众教育。     

Holocene reef evolution in a macrotidal setting: Buccaneer Archipelago,Kimberley Bioregion,Northwest Australia

This study uses information derived from cores to describe the Holocene accretion history of coral reefs in the macrotidal (up to 11 m tidal range) Buccaneer Archipelago of the southern Kimberley coast, Western Australia. The internal architecture of all cored reefs is broadly similar, constituting well-preserved detrital coral fragments, predominantly branching Acropora, in a poorly sorted sandy mud matrix. However, once the reefs reach sea level, they diverge into two types: low intertidal reefs that maintain their detrital character and develop relatively narrow, horizontal or gently sloping reef flats at approximately mean low water spring, and high intertidal reefs that develop broad coralline algal-dominated reef flats at elevations between mean low water neap and mean high water neap. The high intertidal reefs develop where strong, ebb-dominated, tidal asymmetry retains seawater over the low tide and allows continued accretion. Both reef types are ultimately constrained by sea level but differ in elevation by 3–4 m.     

钦州湾越冬鸻鹬类对不同生境利用分析

2008年12月至2009年1月及2011年12月至2012年1月先后两次对钦州湾的越冬鸻鹬类进行了调查,对越冬鸻鹬类退潮后在各类型生境的分布情况和原因进行了分析,以期为制定有效保护越冬鸟类及其生境的措施提供科学依据。结果表明,在不同的天气情况下退潮后各生境内记录到的鸻鹬类物种数和种群数量均不同,钦州湾不同生境鸻鹬类结构特征随天气变化改变。相似性比较显示,晴天各生境中鸻鹬类相似性指数最高的是盐田-养殖塘生境和农田生境,相似性指数为0.96;鸻鹬类相似性指数最低的是红树林滩涂生境和光滩生境,相似性指数为0.49。阴冷天气各生境中鸻鹬类相似性指数最高的是光滩生境和盐田-养殖塘生境,相似性指数为0.79;最低是红树林滩涂生境和光滩生境,相似性指数为0.52。分析表明人类活动的干扰对越冬鸻鹬类生境选择的影响较大。     

The ecology,behaviour and physiology of fishes on coral reef flats,and the potential impacts of climate change

Reef flats, typically a low‐relief carbonate and sand habitat in shallow water leeward of the reef crest, are one of the most extensive zones on Pacific coral reefs. This shallow zone often supports an abundant and diverse fish assemblage that is exposed to more significant variations in physical factors, such as water depth and movement, temperature and ultraviolet (UV) radiation levels, than most other reef fishes. This review examines the characteristics of reef flat fish assemblages, and then investigates what is known about how they respond to their biophysical environment. Because of the challenges of living in shallow, wave‐exposed water, reef flats typically support a distinct fish assemblage compared to other reef habitats. This assemblage clearly changes across tidal cycles as some larger species migrate to deeper water at low tide and other species modify their behaviour, but quantitative data are generally lacking. At least some reef flat fish species are well‐adapted to high temperatures, low oxygen concentrations and high levels of UV radiation. These behavioural and physiological adaptations suggest that there may be differences in the demographic processes between reef flat assemblages and those in deeper water. Indeed, there is some evidence that reef flats may act as nurseries for some species, but more research is required. Further studies are also required to predict the effects of climate change, which is likely to have multifaceted impacts on reef flats by increasing temperature, water motion and sediment load. Sea‐level rise may also affect reef flat fish assemblages and food webs by increasing the amount of time that larger species are able to forage in this zone. The lack of data on reef flats is surprising given their size and relative ease of access, and a better understanding of their functional role within tropical marine seascapes is urgently required.     

Untersuchungen an Plattfischen und Nordseegarnelen(Crangon crangon) im Eulitoral des Wattenmeeres nach dem Übergang zum Bodenleben

In spring and early summer,Pleuronectes platessa, Platichthys flesus, Solea solea, andCrangon crangon transform to benthic postlarvae in the shallow water region of the North Frisian Wadden Sea (eastern North Sea). During the first weeks after metamorphosis, they remain in the puddles and drainage gulleys on the tidal flats that are exposed during low tide. Positive rheotaxis prompting the juveniles to swim against the ebb tide currents is an important mechanism for maintaining their position on the flats. When sunlight intensity increases, they continue their locomotory and feeding activity, even during daytime, in the pools still present at low tide. On warm, cloudless days, temperature levels in these pools may increase to lethal thresholds. Consequently, the animals attempt to escape from higher tidal flats near the shore through the drainage gulleys. Such migrations bring about changes in their distribution patterns. Plaice can scarcely be found in near-shore areas, and they are absent at both high and low tide. The responses observed were correlated to physical and chemical data recorded during the observation period. The ecological significance of tidal pools as habitats is discussed.     

Mangrove inundation and nutrient dynamics from a GIS perspective

A digital elevation model describing topography, tide elevation and inundation degree and frequency of a mangrove forest in North Brazil is discussed in relation to existing phosphate and physicochemical data in waters of an adjacent tidal creek. Due to smooth topography, an increase of 20 cm in tidal height above average neap tides increases flooded area from about 50 to 80%. Analysis of the relationship between microtopography, tidal height and flooding rate showed that in the upper 60 cm of the mangrove forest, increases of 20 cm in topographical height resulted in a doubling of the inundation frequency. This can be particularly relevant for the analysis of nutrient mobilization and vegetation structure of infrequently inundated wetlands. Throughout the year, low-tide phosphate in creek water was inversely proportional to the maximum area flooded during high tide, this correlation being higher during the dry season. Similarly, the inverse relationship between flooded areas and low-tide/high-tide pH ratios was highly significant during the dry season and the beginning of the rainy season. Although the high correlations obtained are based on data pairs obtained at high and low tide, it has to clarified whether the association between inundation degree and creek water pH is relevant for the stability of P compounds in sediment on the short scale of a tidal cycle.     

Large spatial variability in lifetime egg production in an intertidal Baltic tellin (Macoma balthica) population

The extent to which it pays settling larvae of marine benthic organisms to actively select the habitat where they will spend the rest of their life can only be fully appreciated if the fitness consequences of such habitat selection processes are known. We estimated the lifetime egg production of the tellinid bivalve Macoma balthica at 11 sites over a tidal gradient in the western Wadden Sea, using a 30-year data series. The difference in individual lifetime egg production between the best sites in the lower tidal zone and the poorest sites on the high tidal flats was about a factor 10. The differences in lifetime egg production were related to differences in growth and, more importantly, survival. We argue that the large observed differences in reproductive output do not necessarily imply a lack of active habitat selection. As most animals start their last migration before final settlement from the high tidal flats, the choice may be one between a long and risky migration with a low chance of reaching the good habitat versus a more certain but poor existence on the high tidal flats. Electronic Publication     

Contact with water functions as a Zeitgeber for the circatidal rhythm in the mangrove cricket Apteronemobius asahinai

The mangrove cricket Apteronemobius asahinai shows a circatidal rhythm in its locomotor activity, and this rhythm was shown to be entrained to artificial tidal cycles in the laboratory. To examine the Zeitgeber for this rhythm, in the present study, crickets were fixed with insect pins to prevent their body locomotion and a water stimulus was given to them by soaking in water, while recording their locomotor activities. A single water stimulus delayed the phase when given in the middle subjective low tide and advanced the phase when given in the later subjective low tide, whereas it had only a slight effect in the subjective high tide. We conclude that contact with water functions as a Zeitgeber for the circatidal rhythm.     

Carbon and nutrient exchange of mangrove forests with the coastal ocean

Mangrove forests exchange materials with the coastal ocean through tidal inundation. In this study, we aim to provide an overview of the published data of carbon (C) and nutrient exchange of mangrove forests with the coastal ocean at different spatial scales to assess whether the exchange is correlated with environmental parameters. We collected data on C (dissolved and particulate organic C; DOC and POC) and nutrient exchange (dissolved and particulate nitrogen, N and phosphorus, P) and examined the role of latitude, temperature, precipitation, geomorphological setting, hydrology, dominant mangrove species and forest area in explaining the variability of the exchange. We identified that there are a range of methodologies used to determine material exchange of mangroves with the coastal zone, each methodology providing data on the exchange at different spatial scales. This variability of approaches has limited our understanding of the role of mangroves in the coastal zone. Regardless, we found that mangrove forests export C and nutrients to the coastal zone in the form of litter and POC. We found that precipitation is a major factor influencing the export of C in the form of litter; sites with low annual precipitation and high mean annual temperatures export more C as litter than sites with high precipitation and low temperature. Furthermore, export of POC is higher in zones with low mean annual minimum temperature. Identification of broad-scale trends in DOC and dissolved nutrients was more difficult, as the analysis was limited by scarcity of suitable studies and high variability in experimental approaches. However, tidal amplitude and the concentration of nutrients in the floodwater appears to be important in determining nutrient exchange. The strongest conclusion from our analysis is that mangrove forests are in general sources of C and nutrients in the form of litter and POC and that they are most likely to be exporting C subsidies in dry regions.     

Behavior of the groundwater in a riverine-type mangrove forest

The behavior of groundwater and physical properties of bottom sediment in a riverine-type mangrove forest which is composed of a tidal creek and fringing mangrove swamps were investigated through field observations at Iriomote Island, Japan. After the tidal water ebbed from the swamp surface to the creek, groundwater levels at swamp sites near the creek fell by up to 15 cm by the next flood tide, although the fall was negligible at sites far from the creek and at the open coast outside the mangrove forest. The amount of groundwater discharged to the creek from the swamp depended strongly both on the tidal range and the presence of the steep bank which separates the tidal creek from the fringing mangrove swamp. Based on the fall of groundwater level, the bulk hydraulic conductivity of the swamp was estimated to be 1.5×10⁻² cm/s. This value is two to three orders of magnitude larger than that measured in a laboratory using small scale sediment core samples collected in the swamp. These results suggest that the presence of crowded, intricate and large animal burrows as well as sediment layers rich in mangrove humus increases permeability in the mangrove swamp. Further, it is suggested that the mangrove topography with the steep bank of the tidal creek plays an important role which enhances material exchanges through groundwater between the mangrove swamp and the adjacent offshore waters.