印度尼西亚北苏拉威西红树林生态系统碳库研究

近年来的研究指出红树林在海岸带碳固定和碳储存方面发挥着重要的作用。尽管印度尼西亚的红树林面积在全球占很大的比重,对于该地区红树林的有机碳储量和土壤有机碳来源的认识仍有限。本研究调查了印度尼西亚北苏拉威西海洋型的Wori红树林中生态系统有机碳储量及其空间分布特征,以及土壤有机碳的来源,以期加深该地区红树林“蓝碳”功能的认识。研究结果显示,Wori红树林0-50cm深度土壤中有机碳储量为15.4 kg/m²,占生态系统碳储量的主要部分（65%）。红树植物生物量和生态系统碳储量分别为8.3 kg/m²和23.7 kg/m²。土壤有机碳储量在不同离岸距离的采样站位中未表现出显著的空间分布差异,而生物量碳储量则在外滩最高。¹³C稳定同位素分析结果表明红树林土壤中蓄积的有机碳主要来源于红树林有机质,而潮水中的悬浮有机质和红树林外缘的海草并不构成红树林土壤有机碳的重要来源,它们的贡献者都低于20%。研究结果进一步证实了热带地区海洋型红树林湿地在碳储存以及红树植物对碳固定方面的重要性。     

Transport of nutrients and organic matter in a mangrove swamp

Field observations of the tidal transport of nutrients and organic matter in a mangrove swamp on Ishigaki Island, Okinawa, Japan revealed that groundwater flow from the swamp plays a significant role in increasing concentration of dissolved inorganic phosphorous and organic matter in a major channel. In contrast, dissolved inorganic nitrogen is transported from the mangrove swamps via surface water flow in the small channels of the swamp.     

Rapid sediment accumulation and microbial mineralization in forests of the mangrove Kandelia candel in the Jiulongjiang Estuary, China

Rates of sediment accumulation and microbial mineralization were examined at three Kandelia candel forests spanning the intertidal zone along the south coastline of the heavily urbanized Jiulongljiang Estuary, Fujian Province, China. Mass sediment accumulation rates were rapid (range: 10–62 kg m⁻² y⁻¹) but decreased from the low- to the high-intertidal zone. High levels of radionuclides suggest that these sediments originate from erosion of agricultural soils within the catchment. Mineralization of sediment carbon and nitrogen was correspondingly rapid, with total rate of mineralization ranging from 135 to 191 mol C m⁻² y⁻¹ and 9 to 11 mol N m⁻² y⁻¹; rates were faster in summer than in autumn/winter. Rates of mineralization efficiency (70–93% for C; 69–92% for N) increased, as burial efficiency (7–30% for C; 8–31% for N) decreased, from the low-to the high-intertidal mangroves. Sulphate reduction was the dominant metabolic pathway to a depth of 1 m, with rates (19–281 mmol S m⁻² d⁻¹) exceeding those measured in other intertidal deposits. There is some evidence that Fe and Mn reduction-oxidation cycles are coupled to the activities of live roots within the 0–40 cm depth horizon. Oxic respiration accounted for 5–12% of total carbon mineralization. Methane flux was slow and highly variable when detectable (range: 5–66 μmol CH₄ m⁻² d⁻¹). Nitrous oxide flux was also highly variable, but within the range (1.6–106.5 μmol N₂O m⁻² d⁻¹) measured in other intertidal sediments. Rates of denitrification were rapid, ranging from 1106 to 3780 μmol N₂ m⁻² d⁻¹, and equating to 11–20% of total sediment nitrogen inputs. Denitrification was supported by rapid NH₄ release within surface deposits (range: 3.6–6.1 mmol m⁻² d⁻¹). Our results support the notion that mangrove forests are net accumulation sites for sediment and associated elements within estuaries, especially Kandelia candel forests receiving significant inputs as a direct result of intense human activity along the south China coast.     

海南八门湾红树林柱状沉积物中有机生物标志物的分布和降解

对海南岛红树林柱样中有机生物标志物等生物地球化学参数进行了初步研究.结果显示红树林中有机碳(OC)与总氮(TN)比值范围为5.35-7.47,碳稳定同位素(δ13C)值范围为-25‰--22.9‰.脂肪酸与正构烷烃浓度分布范围分别为7.8-21.8μg·g-1(干重)和3.2-25μg·g-1(干重).在表层沉积物中,红树林植物、细菌与浮游生物的脂肪酸生物标志物各占总脂肪酸的25.4%、12.9%和7.5%,结合较低的OC/TN比值和较高的δ13C值,表征了当地微生物和外源浮游植物的有机质贡献.各类脂肪酸在柱样中表现出不同的降解特征:多不饱和脂肪酸(PUFAs)优先被降解,而长链脂肪酸(LCFAs)则较为稳定,没有明显的降解.碳优势指数(CPI)和平均碳链长度(ACL)显示,埋藏深度越深,有机物的生物化学改造程度越大.     

Intertidal substrate modification as a result of mangrove planting: Impacts of introduced mangrove species on sediment microfacies characteristics

A programme of mangrove planting has been undertaken around the island of Rodrigues (SW Indian Ocean) since the mid-1980’s involving the introduction of the species Rhizophora mucronata. We examined three coastal embayment sites (Baie Diamant, Anse Goeland and Anse Pansia) in which planting has been undertaken over different time periods within the past 20 years. Planting has met with variable success in the different sites, probably due to variations in fluvial and groundwater influence. At two sites (Baie Diamant – first planted in 1990, and Anse Pansia – first planted in 1995) ecological data indicates that the mangroves are becoming well-established, and sedimentary evidence suggests that relatively rapid modification of intertidal substrates has occurred. This is evident in the form of significant increases in sediment organic-matter content (especially fibrous organic-matter) and an increase in the accumulation of sediment fines inside the mangroves. A strong correlation exists between the magnitude and depth of substrate modification and mangrove forest density, especially root and sapling density. At the third site, Anse Goeland (first planted in 2001), mangrove establishment has not been successful, many of the seedlings have died and no secondary colonisation has occurred. Sediment substrates show no deviation from background levels in terms of organic content or weight % fines content, and we find no evidence for mangrove planting influencing sediment substrates. Despite evidence for the development of a distinctive mangrove facies at Baie Diamant and Anse Pansia there is, however, no evidence as yet for a marked change in substrate geochemistry such as would be demonstrated by evidence of active bioclast dissolution – a common process in many natural (mature) mangrove substrates. We infer this to be a function of the present relative immaturity of the still developing mangrove substrates, but may also be a function of the apparent paucity of burrowing crabs which play an important role in nutrient cycling and sediment geochemistry. Thus whilst the mangroves in some of the study sites are reaching a stage where they are producing distinctive sedimentary facies, the systems appear to be in a state of progressive sedimentary and diagenetic modification as the floral and infaunal components of the mangroves continue to develop.     

基于国产高分遥感的人工种植红树林种间分类方法研究——以广西茅尾海红树林为例

红树林的种间结构组成对红树林生态系统的健康和发展至关重要,而红树林种间分类问题一直以来都是基于遥感手段的红树林监测中的难点。针对该问题,以人工种植为特点的广西茅尾海红树林遥感种间分类为例,基于面向对象的分类思想,提出了一种现场样本与分割对象相结合的红树林种间分类方法。利用GF-2 PMS1高分辨率卫星遥感影像数据,开展了广西茅尾海红树林湿地典型植被精细分类和空间分布研究,并将分类结果与基于像素和传统面向对象SVM分类方法进行了对比。结果显示:总体上,面向对象分类方法更适合用于茅尾海红树林湿地典型植被分类;对于局部混生明显的区域使用基于像素SVM分类方法效果会更好;传统面向对象分类方法中将整个影像分割对象单元作为训练样本可能会在某种程度上造成负面影响。因此,使用文中提出的样本选择新方法进行面向对象分类精度最高,总体精度达到了93.13%,Kappa为0.89。     

Sources and distributions of terrigenous organic matter in a mangrove fringed small tropical estuary in South China

The sources and distributions of terrigenous organic matter (OM) were investigated in a small tropical estuary in the Hainan Island, South China. Plants, suspended particulate matter (SPM), and surface sediments samples in the estuary and coast were collected. Bulk properties [organic carbon (OC%), total nitrogen (TN%), stable carbon isotope (δ13C) and grain size] and lignin phenol concentrations were measured. OC% of mangrove plants was (43.4 ± 2.1)%, which is similar to the values reported for mangrove plants in other regions. OC% of sediment samples ranged from 0.07% to 1.42%, and they were related to the sediment texture. Lignin phenols in the sediment ranged from 5.16 mg/100 mg OC in the uppermost station to 0.51mg/100mg OC in the coast. The molar ratio of organic carbon to total nitrogen (C/N) (～7) and δ 13 C (～-31.1×10-3 ) of riverine SPM revealed that the major OM sources of riverine SPM were aquatic OM (phytoplankton and/or bacteria). Moreover, the lower lignin concentration (Λ8) and higher (Ad/Al)v of lignin phenols suggest that terrestrial OM in riverine SPM were mainly from soil. Furthermore, C/N ratio, δ13C and lignin phenols reveal that mangrove plants were the predominant OM sources of mangrove surface sediment. Based on the δ13C and lignin phenols, it can be concluded that the major OM sources in estuarine and coastal surface sediments were marine phytoplankton, riverine SPM and mangrove surface sediment. In addition, the higher (Ad/Al)v of lignin phenols in those coastal sediments indicate that seagrass might be a potential OM source in coastal sediments, however, the lower (Ad/Al)v in the estuarine sediments in turn suggests that seagrass could not be transported to the mangrove fringed region. A three-end-member model which is based on lignin concentrations and δ13C was applied to evaluate the contribution of mangroves to the organic matter preserved in the surface sediments. Around the mangrove fringed region, mangrove could contribute more than 50% to the sedimentary OM, and this value is much higher than riverine OM. Nevertheless, mangrove OM could not be efficiently transported to the coastal region. Our study suggests that mangrove forest is an important OM source in this small estuary.     

浙江省红树林分布和造林成效分析

基于不同时期浙江省红树林造林数据及林分生长监测,分析浙江省红树林时空变化和区域造林生长差异。结果表明:(1)截止到2020年浙江省红树林面积总计386.77hm²,其中温州市257.01hm²,台州市129.76hm²,主要造林树种为秋茄(Kandelia obovata)(368.48hm²)和苦槛蓝(Myoporum bontioides)(18.29hm²);(2)不同时期红树林面积占现有总面积的比例分别为0.11%(2000年前)、3.72%(2000—2010年)、36.17%(2011—2015年)和59.99%(2016—2020年);(3)2000年以前和2000—2010年的秋茄平均株高分别为205.5cm和246.13cm,林分盖度分别高达67.69%和77.90%;2011—2015年和2016—2020年秋茄株高分别为106.63cm和50.17cm;盖度分别为68.66%和24.56%;(4)不同区域红树林种植区滩涂沉积物中碱解氮、速效钾、有机质和含盐...     

基于阶跃函数的红树林凋落物变化模型研究

由于凋落物随时间变化而存在峰值,按一般的回归方法或分段拟合方法均不能建立理想的凋落物随时间变化的模型。利用阶跃函数,解决了分段模型一直无法解决的两个问题:一是变点的数学确定方法,另一个是变点的连续性问题。建立了基于符号函数的阶跃函数模型,并以此为基础,提出了具有峰值的凋落物耦合模型。为了检验凋落物模型的效果,以雷州半岛红树林为例,结果表明,决定系数0.8以上,回归模型达到显著性水平。     

Seasonal and spatial variation in species diversity, abundance, and element accumulation capacities of macroalgae in mangrove forests of Zhanjiang, China

The objective of this study was to investigate whether there was distinctive seasonal and zonal variation in the species diversity, biomass, and element accumulation capacities of macroalgae in two major intertidal mangrove stand types （Avicennia marina assemblage andSonneratia apetala assemblage） in the Zhanjiang region of southern China. Over a year, 31 species in 15 genera were identified in both mangrove assem-blages, of which the dominant species wereCladophoropsis zollingeriand Enteromorpha clathrat.Macroal-gal species were significantly most abundant in spring （p〈0.05）, followed by summer, winter, and autumn. Variation in the zonal distribution of macroalgal species was conspicuous in both intertidal mangrove as-semblages, with the greatest abundance in the middle zone, and the least in the front zone. Patterns in the seasonal and zonal variation in macroalgal biomass in theS. apetalaassemblage were similar to those of macroalgal species diversity in both mangrove assemblages. The seasonal patterns in tissue concentrations of 15 analyzed elements were not uniform among the macroalgaeC. zollingeri,E. clathrata, andGracilaria salicornia in theA. marina assemblage. All three species exhibited variation in their responses to ambient concentrations of different elements, implying their differential ability to absorb and selectively accumulate certain elements.     

1991—2011年廉江红树林分布及变化的遥感分析

利用1991年的1景TM遥感数据,2000年的ETM+遥感数据和2011年HJ-1A遥感数据进行廉江红树林信息的提取。结果表明：1991,2000和2011年廉江的红树林分布面积分别为131.6,628.7和1 056.2 ha。自1991年至2011年红树林呈增加的趋势,共增加924.6 ha,20年间研究区域的红树林约增加了7倍。湛江红树林国家自然保护区的建立对于红树林湿地生态系统的保护和恢复起到极大的促进作用,研究区域红树林造林恢复成果显著,种植了大量的人工红树林。     

海南红树林根系土壤中可培养细菌的多样性分析

为研究海南红树林根系土壤细菌多样性,充分发掘中国红树林特有微生物资源,作者于2012年12月份从10份采集于海南北港岛红树林根系淤泥样品中分离可培养海洋细菌,并基于16S rRNA基因序列分析的方法对样品中的细菌多样性进行研究。共分离得到122株海洋细菌,经并菌后选取其中的70株代表性菌株测序,结果发现它们分为4个类群:变形菌门(主要为γ-变形菌纲)(Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和放线菌门(Actinobacteria),分别占66%,19%,11%和4%。共代表30个属47个种,其中有9个潜在新种和2个潜在新属。本研究结果表明,北港岛红树林中存在着丰富的细菌多样性,很多类群可能是红树林特有细菌物种。     

Primary production and nutrients in a tropical macrotidal estuary, Darwin Harbour, Australia

Tropical estuaries are under increasing pressure worldwide from human impacts, but are poorly studied compared with temperate systems. This study examined a tropical macrotidal estuary, Darwin Harbour, in northern Australia, using a combination of direct measurements and literature values to determine the main sources of primary production and the sources of nutrients supporting growth. The main source of primary production was calculated to be the extensive area of fringing mangroves and resulted in a net autotrophic system (P_G:R = 2.1). Much of the carbon in the mangrove forests appears to be retained within the forests or respired, as the water column was also net autotrophic despite the carbon inputs. Phytoplankton were the second largest primary producer on a whole-of-harbour basis, with low biomass constrained by light and nutrient availability. The phytoplankton were likely to be nitrogen (N) limited, based on low N:phosphorus (P) ratios, low dissolved bioavailable N concentrations (ammonium (NH₄⁺), nitrate (NO₃⁻), urea), and evidence that phytoplankton growth in bioassays was stimulated by NH₄⁺ addition. The largest new source of N to the system was from the ocean due to higher N concentrations in the incoming tides than the outgoing tides. Atmospheric inputs via N fixation on the intertidal mudflats and subtidal sediments were substantially lower. The rivers feeding into the harbour and sewage were minor N inputs. Nitrogen demand by primary producers was high relative to available N inputs, suggesting that N recycling within the water column and mangrove forests must be important processes. Darwin Harbour is adjacent to the rapidly growing urban area of Darwin city, but overall there is no evidence of anthropogenic nutrient inputs having substantial effects on primary production in Darwin Harbour.     

Variations in mangrove forest productivity in northern Australia and Papua New Guinea

A survey method previously developed for estimating potential net primary production (P_N) of mangrove forests was applied at 19 widely separated sites in tropical northern Australia and six sites in the Gulf of Papua. These estimates are compared with previous results for mangrove forests at Hinchinbrook Island, north Queensland. Surveys of soil properties in these areas indicate that low availability of soil phosphorus is a major contributing factor to the consistently in P_N estimates of Cape York and North-western Australian forests (range in P_N=11–26; mean P_N= 19kg C ha^?1 day^?1) compared with the Hinchin-brook Island and Gulf of Papua forests (range in P_N=3–38; mean P_N=26 kg C ha^?1 day^?1). The regional variation and possible effects of other soil properties, such as redox potential and salinity, are discussed briefly. It is suggested that the generally low salinities and moderate soil redox status may partially offset the effects of low soil P in the Cape York region.     

深圳福田红树林区7种红树植物叶热值的季节变化

对广东深圳福田红树林自然保护区的7种红树植物叶热值和灰分含量的季节变化进行了研究.结果表明:(1)7种红树植物叶的灰分含量存在差异,且具有一定的季节变化;(2)7种红树植物叶中,大戟科的海漆、梧桐科的银叶树这两种红树植物叶的干重热值与灰分含量具有极显著的线性相关,其余5种红树植物叶的干重热值与灰分含量相关性不显著;(3)从干重热值的季节变化来看,2001年1月(冬季)、2001年4月(春季)7种红树植物叶的干重热值与灰分含量有极显著的线性相关,2000年7月(夏季)7种红树植物叶的干重热值与灰分含量有显著的线性相关,2000年10月(秋季)7种红树植物叶的干重热值与灰分含量相关性不显著;(4)7种红树植物叶的去灰分热值与干重热值存在不同的季节变化趋势,但7种红树植物叶的去灰分热值均是秋季最高.     

海南常见红树植物叶片脂肪酸组成

脂肪酸的组成分析对认识红树植物脂肪酸资源、红树林生态系统内部的营养关系、食物网的结构,以及红树植物对生境的适应等具有重要参考价值。本研究分析了海南岛铁炉港和清澜港两个港湾的红海榄(Rhizophora stylosa)、杯萼海桑(Sonneratia alba)、木果楝(Xylocarpus granatum)、角果木(Ceriops tagal)、榄李(Lumnitzera racemosa)、木榄(Bruguiera gymnorrhiza)和正红树(Rhizophora apiculata)等7种不同红树植物叶片中脂肪酸的组成及含量。在样品中共检测出25种脂肪酸,其中月桂酸、棕榈酸和肉豆蔻酸等8种存在于所有样品中。样品中含量最高的饱和脂肪酸均为棕榈酸(占比44.32%),其次为硬脂酸(占比7.74%),不饱和脂肪酸含量较高的有油酸(占比7.61%)、亚油酸(占比9.81%)和二十碳烯酸(占比12.16%)。植物样品的脂肪酸不饱和指数为0.24～1.13。除木果楝和清澜港采集的木榄样品外,其余样品种的不饱和脂肪酸含量均低于饱和脂肪酸。铁炉港的红海榄、杯萼海桑、角果木和榄李4种植物叶...     

广西钦州湾百年来红树林演变的有机碳同位素和孢粉示踪及其影响因素

气候变化和人类活动制约下的红树林演变是一种长时间尺度效应,而沉积物则是记录这种响应的最佳档案。采用古生态学研究思路,选择有效的示踪参数是解读这一档案的有效途径。本文通过广西钦州湾红树林区1根柱状沉积物中有机碳同位素(δ13C)、C/N分析和孢粉鉴定,以沉积物中的红树林源有机碳贡献和红树植物孢粉组合为示踪参数,在210Pb年龄框架构建的基础上,通过对比研究红树林源有机碳贡献和红树孢粉组合特征,揭示百年来钦州湾红树林兴衰和群落演替规律;进而重塑其红树林演变历史:兴盛期(1864-1918年)、衰退期(1918-1968年)和低谷期(1968-2007年),这与土地替代、遥感分析和现场勘测数据较为吻合。结合气候变化和人类活动资料,发现钦州湾红树林的近期衰退主要源于人类活动的影响,尤其是虾塘围垦;而与气候变化关系不大。     

Morphology, hydrography and sediment dynamics in a mangrove estuary: The Konkoure Estuary, Guinea

The Konkouré Estuary in the Republic of Guinea is a poorly understood atypical mangrove system. Sediment dynamics in tropical estuaries are controlled by a combination of processes including river discharge, morphology, salinity, erosion and deposition processes, the settling of mud, physico-chemical processes and mangrove swamps. Here we present a consistent set of data aimed at characterising the estuary and thus, increasing our understanding of tropical systems, as well as studying the impact of human intervention in the region. Water elevations, current measurements, salinity, suspended sediment concentrations, bathymetry and sediment cover are presented following a 3 year survey of the Konkouré Estuary. Here we provide conclusive evidence that the Lower Konkouré is a shallow, funnel shaped, mesotidal, mangrove-fringed, tide dominated estuary, well mixed during low river discharge. The estuary becomes stratified during high river flows and spring tides whereas a salt wedge appears during neap tides. The Konkouré Estuary has been described as hypersynchronous, and has three terminal outlets, two of which are landward-directed, attesting to a tidal pumping effect, while the third one is seaward-directed, and is controlled by the mangrove. The suspended matter is transported by the tidal effect within the middle estuary and is therefore trapped in the Turbidity Maximum zone (TMZ). The location of the TMZ is river-controlled and is correlated with residual currents but not with salinity front. A dam, constructed 130 km upstream, impacts on the hydrodynamics, and reduces the salinity intrusion by about 25%. It causes an increased low river discharge whereas its efficiency over high river flows is unclear.     

Spatiotemporal variations in the organic carbon accumulation rate in mangrove sediments from the Yingluo Bay,China, since 1900

Mangroves can not only provide multiple ecosystem service functions, but are also efficient carbon producers,capturers, and sinks. The estimation of the organic carbon accumulation rate(OCAR) in mangrove sediments is fundamental for elucidating the role of mangroves in the global carbon budget. In particular, understanding the past changes in the OCAR in mangrove sediments is vital for predicting the future role of mangroves in the rapidly changing environment. In this study, three dated sediment cores from interior and fringe of mangroves in the Yingluo Bay, China, were used to reconstruct the spatiotemporal variations of the calculated OCAR since 1900 in this area. The increasing OCAR in the mangrove interior was attributed to mangrove flourishment induced by climate change characterized by the rising temperature. However, in the mangrove fringe, the strengthening hydrodynamic conditions under the sea level rise were responsible for the decreasing OCAR, particularly after the1940 s. Furthermore, the duration of inundation by seawater was the primary factors controlling the spatial variability of the OCAR from the mangrove fringe to interior, while the strengthened hydrodynamic conditions after the 1940 s broke this original pattern.     

从海南岛全新世孢粉研究看海滨红树林的演化

海南岛是我国第二大岛,位于18°09'～21°10'N,108°03'～110°03'E北隔琼州海峡与雷州半岛相望.海岸线长达1500km,全岛面积为33900km2,四周地形低,中南部山地耸立,海拔100m以下的台地、平原占全岛面积的近2/3.