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1.
福建沿岸地区红树林的种类与分布   总被引:11,自引:0,他引:11  
于1998年11月至1999年1月对福建沿岸地区的红树林进行了调查,就福建红树林的种类组成、面积、分布情况、人工造林情况进行了论述,并就制约福建发展红树林的因素及解决方法提出了一些建议。  相似文献   

2.
文章以福建省漳江口国家级红树林自然保护区为研究区, 提出了一种联合星载光学和合成孔径雷达(SAR)影像的红树林与互花米草分布的自动提取算法, 提取研究区内红树林和互花米草的空间分布。本研究选择2016年、2017年和2018年各一景低潮时的Sentinel-2 A光学影像数据, 获取植被和其他地物的光谱和纹理信息。算法首先基于归一化植被指数、增强型植被指数、地表水分指数以及数字高程模型的相关规则计算红树林和互花米草的潜在分布区; 通过随机森林分类算法区分红树林和互花米草, 2016年、2017年和2018年影像的分类总体精度和Kappa系数分别为98.53%和0.980、96.52%和0.952、98.71%和0.978, 分类效果良好; 使用当年所有Sentinel-1 A/B的SAR影像获得研究区的常年海水分布范围, 使用与海水交界的判据, 实现红树林、互花米草提取范围的优化。研究表明, 研究区2016年、2017年和2018年红树林总面积分别为56.85hm2、59.88hm2和58.61hm2, 互花米草总面积分别为109.23hm2、124.00hm2和142.39hm2, 与前人的研究成果在红树林和互花米草的空间分布和面积量级上有较好的一致性。  相似文献   

3.
福建红树林上钻孔动物的生态   总被引:1,自引:0,他引:1  
黄戚民  周时强 《台湾海峡》1996,15(3):305-309
福建红树林上的钻孔动物共发现了5种,其中软体动物的龙骨节铠船蛆Bankia carinata、裂铠船蛆Teredo manni和甲壳动物的光背团水虱Sphaeroma retrolaevis是破坏红树林的主要的钻孔动物。钻孔动物钻凿红树茎的基部和裸露的根部,垂直分布受潮汐水位制约,在红树林区的纵深分布与水流畅通程度有关。  相似文献   

4.
通过总结目前红树林面临的各类生态退化机制,利用"压力-状态-响应(PSR)"分析模型,构建了红树林生态退化机制评估指标体系,并应用于福建省漳江河口红树林生态系统的案例研究.评价结果显示:漳江河口红树林生态退化压力仍处在较小的范围内,主要压力源来自生物入侵以及海岸带水产养殖和围垦;对影响显著的生态退化因子已经采取了有效的控制措施;保持并加强保护措施,将有助于当地红树林生态系统在未来维持稳定的状态.  相似文献   

5.
对中国红树林物种组成、资源状况和分布特征进行了调查和评价.结果表明,中国红树林天然分布南界为海南三亚(18°12′N),北界为福建福鼎(27°20′N)(人工引种北界为浙江乐清28°25′N).中国红树林区系有红树植物20科26属37种.广东、广西和海南沿海是中国红树林的主要分布地区.近50 年来,红树林面积先是锐减(1950年,48 266 hm2;1997年,14 877 hm2),2000年后略有回升(2002年,22 024.9 hm2;2008年,23 081.5 hm2).合理评估红树林湿地生态效价,完善红树林保护区制度,推进红树林湿地生态修复工程,构建红树林湿地保护网络系统,是中国红树林资源保护性开发利用的可行对策.  相似文献   

6.
This paper deals with the reaction of the contents of carbohydrate and nitrogenous compound in leaves of mangroves (Kandelia candel and Aegiceras corniculatum) to the change of seabeach soil salinity (range: 3-12) in the tidal swamp of Jiulongjiang River, Fujian Province, China.Results obtained show that: (i) contents of total sugar, starch and soluble sugar in the leaves of those mangrove plants would increase with increase in the soil salinity; (ii) with increase in the soil salinity, contents of total nitrogen and soluble protein in their leaves would decrease, but fluctuate at the soil salinity more than 10.  相似文献   

7.
福建九龙江口红树植物分子分类的研究   总被引:4,自引:0,他引:4  
周涵韬  林鹏  孙晟 《海洋科学》2001,25(8):42-46
运用RAPD技术对福建九龙江口龙海红树林自然保护区浮宫种苗园内白骨壤(Auicenmia marina),桐花树(Ageiceras corniculatum),无瓣海桑(Sonneratia apatala),秋茄(Kandeliacandel),木榄(Bruguiera gymnorthiza),海莲(B.sexangula),尖瓣海莲(B.sexangula var,rhynchopetala)等7种红树植物进行了遗传多样性分析,从30个10-mer随机引物中筛选出15个有效引物,利用这15个有效引物共扩增出630条DNA带,其中多态性条带535条,占总扩增条带的84.92%,利用Nei指数法得出7种红树植物间的遗传一致度和遗传距离,并运用UPGA统计分析法对红树植物的7个种间的亲缘关系进行聚类分析,7个种分为A,B两个大组,白骨壤,酮花树,无瓣海垒同属于A组,秋茄,木榄,海莲,尖瓣海莲分聚类在B组,分子聚类结果和传统的分类学相吻合,由此表达这15个有效引物的PAPD分子标记技术能较为客观地反庆出红树植物种间的遗传亲缘关系,并为从分子水平研究红树植物遗传多样性,保护,开发和利用红树林资源提供科学依据。  相似文献   

8.
The study aims to compare the differences of macrofauna communities of wetlands at 3-year-forest- age, 5-year-forest-age Sonneratia apetala artificial mangroves, 5-year-forest-age Kandelia candel ar- tificial mangroves with the same restoration background, and the naked tidal flat in the Qi’ao Island Mangrove Nature Reserve of Zhuhai, Guangdong Province. The results show that there were signif- icant structural differences in macrofauna communities among four kinds of habitats. The increase of biomass and species diversity of macrofauna at 3-year-forest-age S. apetala artificial mangroves was obviously faster than that at 5-year-forest-age K. candel artificial mangroves whose average tree height was close to that of 3-year-forest-age S. apetala artificial mangroves. The BIOENV analysis shows that it was related to the rapid growth of S. apetala, which rapidly changed the light level and shading conditions in the forests. The 5-year-forest-age S. apetala artificial mangroves had lower macrofauna species diversity but higher density and biomass than K. candel artificial mangroves with the same forest age. This was due to the rapid changes of physical and chemical properties of habitat soil by the ecological restoration of S. apetala artificial mangroves as well as the changed food sources possibly caused by the leaf-litter of such non-indigenous mangrove species S. apetala. However, further survey should be conducted on whether there are any negative ecological impacts of large-scale cultivation of S. apetala on macrofauna communities, so as to evaluate correctly S. apetala’s role in the restoration of coastal mangrove ecosystems.  相似文献   

9.
The mangrove, Avicennia marina var. resinifera in a tidally-flooded explosion crater, Tuff Crater, near the southern latitudinal limit of mangroves in New Zealand adopts two distinct growth forms, taller tree-like mangroves up to 4 m tall along the banks of the tidal creek, and low stunted shrub mangroves less than 1 m tall on the mudflats. Twelve trees were felled and on the basis of a biomass/height relationship for the taller trees and a biomass/canopy width relationship for the lower, above-ground biomass (excluding pneumatophores) was estimated. Average above-ground biomass for the taller mangrove was estimated to be 104·1 t ha?1 and for the lower 6·8 t ha?1. While the value for the taller mangroves is similar to figures reported for more complex tropical mangroves, the fact that 94% of the basin is covered by low generally sparse mangroves means that total biomass for the basin is estimated to be 153 t, an average of only 7·6 t ha?1. Litter-fall beneath the taller mangroves is estimated as 7·6±2·5 t ha?1 a?1 and beneath the lower mangroves 3·3±0·5 t ha?1 a?1. The value for the taller mangroves is similar to that reported from mangroves in many other parts of the world, but because of the extensive low sparse mangroves the total for the basin is estimated as 53·7 t a?1, an average rate of 2·7 t ha?1 a?1, a very low rate of litter-fall when compared with elsewhere. Decomposition of mangrove leaves occurs relatively rapidly with leaves losing half their dry weight in 10 weeks and then continuing to degrade but at a slower rate. Substrate sediment samples contain high organic matter content, and although some organic matter appears to be exported via the tidal creek, a proportion of the detrital production is evidently recycled in situ.  相似文献   

10.
Coastal mangroves, dwelling at the interface between land and sea, provide an important contribution to reducing risk from coastal hazards by attenuating incident waves and by trapping and stabilizing sediments. This paper focusses on relations between vegetation densities, wave attenuation rates, sediment characteristics and sedimentation rates in mangroves. These processes were studied along two cross-shore transects through mangroves fringing estuaries in the southern Andaman region of Thailand. Volumetric vegetation densities in these mangroves were ranging up to 32‰, depending on the water depth. Generalized total wave attenuation rates increased from 0.002 m 1 in the sparsely vegetated forest fringes with Avicennia and Sonneratia species, up to 0.012 m 1 in the dense Rhizophora vegetation in the back of the forests. The total wave attenuation rates integrate effects of shoaling and energy losses due to various bio-physical interactions within the mangrove ecosystem. Wave attenuation in the mangroves is presumably dominated by energy losses due to vegetation drag, since wave attenuation due to bottom friction and viscous dissipation on the bare mudflats is significantly lower than those inside the mangrove vegetation.Additionally, wave attenuation in the mangroves was found to facilitate enhanced net sediment deposition and a gradual fining of the bed material. These findings corroborate the coastal defence function of mangroves by quantifying their contribution to wave attenuation and sediment trapping. The explicit linking of these properties to vegetation composition and structure facilitates modelling studies investigating the mechanisms determining the coastal defence capacities of mangroves.  相似文献   

11.
红树林遥感智能分类方法研究   总被引:13,自引:0,他引:13  
滕骏华  刘宇 《台湾海峡》1997,16(3):331-338
利用GIS信息中的红树林地域分布规律作向导,充分利用械树林区的光谱信息进行红树林植被信息提取。在对比研究常规的红树林图象自理方法的基础上,提出了适用于红树林植被信息遥感监测的智能分类方法。  相似文献   

12.
Coastal wetlands provide important ecological services to the coastal zone, one of which is sediment retention. In this study we investigated sediment retention across a range of geomorphological settings and across vegetation zones comprising coastal wetlands. We selected six coastal wetlands dominated by mangroves over a gradient from riverine to tidal settings in Southeast Queensland, Australia. Each site was comprised of three distinct vegetation communities distributed as parallel zones to the coast line: seaward fringe mangroves, landward scrub mangroves and saltmarsh/ cyanobacteria mat of the high intertidal zone. We measured suspended sediment retention and sedimentation rates. Additionally, in order to assess the origin of sediment transported and deposited in the mangroves, glomalin, a novel terrestrial soil carbon tracer, was used. Our results show a mean average sedimentation of 0.64 ± 0.01 mg cm−2 spring tide−1, which was variable within sites, regardless of geomorphological setting. However, geomorphological setting influenced spatial patterns of sediment deposition. Riverine mangroves had a more homogeneous distribution of sediments across the intertidal zone than tidal mangroves, where most sedimentation occurred in the fringe zone. Overall, the fringe zone retained the majority of sediment entering the coastal wetland during a tidal cycle with 0.90 ± 0.22 mg cm−2 spring tide−1, accounting for 52.5 ± 12.5% of the total sedimentation. The presence of glomalin in suspended sediments, and thus the relative importance of terrigenous sediment, was strongly influenced by geomorphological setting, with riverine mangroves receiving more glomalin in suspended solids than tidal mangroves. Glomalin was also differentially deposited within the vegetation zones at different geomorphological settings: primarily at the fringe zone of tidal mangroves and within the scrub zone of riverine mangroves. The differences we observed in the spatial distribution of sedimentation and the difference in the origin of the sediment deposited in riverine and tidal mangroves are likely to have an impact on ecological processes.  相似文献   

13.
九龙江口红树植物分子分类的初步研究   总被引:5,自引:0,他引:5  
周涵韬  林鹏  郑文竹  孙晟  郑志强  林凡  陈鹭真 《台湾海峡》2001,20(1):66-71,T005
本研究工作以福建九龙江口龙海红树林自然保护区浮宫种苗园内7种红树植物为材料,采用改进的CTAB法获得了纯度较高(A260/A280在1.6~2.0之间),得率高(DNA平均得率约为120×10-6m/m,FreshWeight),片段完整(片段大小约为23kb左右)的基因组DNA,并运用RAPD技术对这7种红树植物进行了遗传多样性分析.从30个10-mer随机引物中筛选出9个有效引物,并利用这9个有效引物共扩增出352条DNA带.利用UPGMA法对红树植物的7个种间的亲缘关系进行聚类分析,得出7个种的DNA分子分类系统图,并与传统的分类进行比较,发现结果相符,从而确定了RAPD技术用于红树植物分子分类研究的可行性,并为从分子水平研究红树植物遗传多样性,保护、开发和利用红树林资源提供科学依据.  相似文献   

14.
The biomass, species composition and diversity of benthic diatom assemblages in mud-flat soils in Kandelia candel (L.) Druce communities with and without vegetation were studied seasonally at the Houyu Bay in Fuding City, Fujian Province, China. A total of 103 taxa were identified (including varieties). Eighty-four taxa were found in the mud-flat with vegetation and 74 taxa in the mud-flat without vegetation, while the biomass was large in January and April and decreased from July to October. The most abundant species in the mud-flat with vegetation are Nitzschia cocconeiformis, Gyrosigma scalproides and N. fasciculata, compared with G. scalproides and N.obtusa var. scalpelliformis in the mud-flat without vegetation. High/P values at 2 sites during all seasons suggest that diatom assemblages in the sediments of the Houyu Bay represent an original environment. Multi-dimensional scaling of diatom assemblages from mud-flats with and without vegetation shows that a slight seasonal change and only a single association occur in the mangroves.  相似文献   

15.
Changes in biotic and abiotic processes following mangrove clearing   总被引:1,自引:0,他引:1  
Mangrove forests, important tropical coastal habitats, are in decline worldwide primarily due to removal by humans. Changes to mangrove systems can alter ecosystem properties through direct effects on abiotic factors such as temperature, light and nutrient supply or through changes in biotic factors such as primary productivity or species composition. Despite the importance of mangroves as transitional habitats between land and sea, little research has examined changes that occur when they are cleared. We examined changes in a number of biotic and abiotic factors following the anthropogenic removal of red mangroves (Rhizophora mangle) in the Panamanian Caribbean, including algal biomass, algal diversity, algal grazing rates, light penetration, temperature, sedimentation rates and sediment organic content. In this first study examining multiple ecosystem-level effects of mangrove disturbance, we found that areas cleared of mangroves had higher algal biomass and richness than intact mangrove areas. This increase in algal biomass and richness was likely due to changes in abiotic factors (e.g. light intensity, temperature), but not biotic factors (fish herbivory). Additionally the algal and cyanobacterial genera dominating mangrove-cleared areas were rare in intact mangroves and included a number of genera that compete with coral for space on reefs. Interestingly, sedimentation rates did not differ between intact and cleared areas, but the sediments that accumulated in intact mangroves had higher organic content. These findings are the first to demonstrate that anthropogenic clearing of mangroves changes multiple biotic and abiotic processes in mangrove forests and that some of these changes may influence adjacent habitats such as coral reefs and seagrass beds. Additional research is needed to further explore the community and ecosystem-level effects of mangrove clearing and their influence on adjacent habitats, but it is clear that mangrove conservation is an important aspect of managing tropical coastal systems.  相似文献   

16.
红树林防护溃坝态海啸波冲击集装箱消能试验研究   总被引:1,自引:1,他引:0  
近年来海啸灾害频繁发生,对海工建筑物造成巨大损失。在以往的海啸事件中,红树林对海啸具有一定的消减作用。基于溃坝原理生成海啸波,进而研究红树林对海啸波消减作用及红树林防护下的海啸冲击集装箱的变迁表征。对闸门处溃坝研究结果表明,溃坝过程包含突然下降、相对稳定、缓慢下降三个阶段,且蓄能水位越高溃坝发生得越剧烈。海啸波冲击搬运集装箱可分为初始冲击、加速、匀速三个阶段,其动力成因包含了冲击力和浮力。红树林消减海啸波的流态表明尾涡重叠产生的紊动水流是消能的主因,合理密植、对称排布、交错排布有利于海啸波能的消减。此外,三角形交错红树林排布、海啸波强度减小、集装箱重度增加、以及海岸坡度增加均有利于减小集装箱的变迁距离。基于试验数据提出了红树林消波系数计算公式,本试验中红树林消波系数范围为0.02至0.42。  相似文献   

17.
《Ocean & Coastal Management》2003,46(9-10):823-844
Economists have always argued that only when people bear true economic costs of using natural resources, such as mangroves, that they will have appropriate incentives to use them efficiently and minimize their degradation and losses. More recently, non-economists, too, have started to call for the use of economic valuation information to argue for conservation of mangroves. This paper briefly examines the role economic valuation information can play, at least theoretically, in encouraging conservation of mangroves and increasing efficiency in resource use. In practice, the paper argues that a number of difficulties are likely to be encountered when determining true economic value of mangroves, particularly when small areas of mangroves are involved. A total reliance on economic valuation-based decision-making is questioned, particularly in the light of minimal ecological information often available in small island nations in the Pacific. An alternative decision-making process is proposed in which the relevance of economic valuation-based decision-making is recognized but at a second tier level.  相似文献   

18.
大亚湾红树林及海岸植物叶片盐腺与表皮非腺毛结构   总被引:1,自引:1,他引:0  
王厚麟  缪绅裕 《台湾海峡》2000,19(3):372-378
光镜下观察研究了大亚湾地区部分红树林和海岸植物叶片的盐腺(腺毛)和非腺毛的结构及部分种类的发育过程,结果表明:在21种植物中,叶片具盐腺的有桐花树、老鼠勒、白骨壤、黄槿、假茉莉、海南刺、二叶红薯,具非腺毛的有黄槿、白骨壤、钝叶豆腐木、草海桐。不同植物盐腺和表皮非腺毛的基本结构一致,反映出对难生境的趋同适应。  相似文献   

19.
Aquaculture is one of the fastest growing food industries. However, the rapid growth of aquaculture worldwide has resulted in growing concerns about its impact on important ecosystems. The expansion of aquaculture farms in the coastal areas has led to conversion of mangroves, more rapidly. To assess the impact of aquaculture on mangroves, the present study has been undertaken in Mahanadi delta of Orissa, East coast of India which is famous for its distinctive mangrove ecosystem. It has undergone tremendous changes due to the development of aquaculture and agriculture activities during last two decades. For this, satellite data of different time periods (Landsat MSS of 1973, Landsat TM of 1990 and IRS P6 LISS III of 2006) were used. It was found that the delta was occupied by dense mangrove (12.6%), open mangrove (3.3%), aquaculture (12.9%) and agriculture (30.9%) in 2006. A loss of 2606 ha mangrove area and an increase of 3657 ha aquaculture area was observed from 1973 to 2006 clearly depicts the augment of aquaculture industry. It is suggested that, regular monitoring of the mangroves and effective implementation of coastal management laws be strictly undertaken to prevent the further loss mangroves in Mahanadi delta.  相似文献   

20.
Management of mangroves in a sustainable ecological as well as economic way is a difficult proposition and needs multi-disciplinary intervention. This paper highlights the importance of criteria and indicators to evaluate the status of performance of communities in managing their mangroves sustainably. The framework developed on the basis of 6 principles, 12 criteria, 36 indicators and 47 verifiers had been applied for assessment of Eco-Development Committees of the Sunderbans, India. Results show the presence of a highly positive correlation between performance of the committees and condition of the mangrove environment. Level of implementation of legal and institutional management strategies to protect mangroves proves to be the essential pre-condition in achieving sustainability. The study further demonstrates the effectiveness of the developed framework in the context of community forestry since the methodology was designed to be simple and flexible so as to apply it in forest management unit level without any major difficulty.  相似文献   

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