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1.
通过样点实地调查,调查到海南清澜省级自然保护区具有真红树植物11科24种,半红树植物15科20种;根据组成种类,群落特征和立地条件,把红树林植物群落划分为12个红树林群系和4个半红树林群系。 相似文献
2.
植物抗氧化研究对寻找高效率、低毒性天然抗氧化剂具有重要的指导意义。以在海南分布较广的红树林植物海莲进行抗氧化活性研究,以期对海莲开发利用的可能性提供理论依据。采用清除DPPH自由基和清除ABTS自由基对海莲不同部位———根、茎、叶、花的乙酸乙酯提取物进行抗氧化能力评价,采用比色法和福林酚法测定总黄酮和总酚含量。结果显示,海莲茎的提取物在4个部位中抗氧化活性最好,清除二者的IC50分别为(0.234±0.053)mg/m L和(0.196±0.080)mg/m L,海莲中酚类物质含量较大,4个部位中茎的总酚含量最多,含量为13.2 mg。说明海莲各部位均显示出了较好的抗氧化能力,具有较好的开发潜力。 相似文献
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红树林是热带和亚热带海岸带上特有的森林群落,为极其独特的生态系统。海南红树林植物种类十分丰富,有红树植物38种,其中真红树植物26种,半红树植物12种,属典型的东方群系。因环境破坏、生境丧失和人为干扰等因素的影响,多数物种的生存环境已遭到严重破坏、群落结构日趋简单;水椰Nypa fruticans、红榄李Lumnitzera littorea、海南海桑Sonnerati hainanensis等物种已处于濒危状态。笔者由此提出"两个核心+四个层面"的恢复手段,即建立种质资源保育基因库、采取红树林复合种植模式、完善红树林立法体系、加强红树林科研深度、提高遥感技术利用水平以及开展湿地生态旅游等多种保护策略,为红树林的生态恢复和园林应用提供参考。 相似文献
5.
经过多年的研究和实践,人们已深刻地认识到,海南省的发展战略应该积极发展服务型、开放型和生态型经济,形成以旅游业为龙头、以现代服务业为主导的特色经济结构。显然要实现这个宏伟的目标,生物多样性的保护和持续利用就是最根本和最关键的问题。如果作为生态旅游基本资源的季节性雨林、红树林、海洋生物资源和农业生物多样性被毁,一切都将是一纸空文。本文就拟简略地探讨一下有关这些方面的问题,并提出一些建议供有关方面参考。 相似文献
6.
W.A. Houston 《Mangroves and Salt Marshes》1999,3(1):29-40
A hailstorm in October 1994 was found to have moderately or severely impacted on 5.3% of the mangrove forests in Port Curtis. All mangrove species showed evidence of hail damage, including the three most common species (Rhizophora stylosa, Ceriops tagal and Avicennia marina). Physical effects of hail damage included stripping of leaves from plants, holes punched through leaves, bruising to bark, divots removed from bark, branch and plant death. Speciesspecific differences in vulnerability to the effects of hail were observed with C.tagal experiencing relatively higher mortality rates than the other two common mangrove species. A delayed pattern of mortality was observed in two species _ C.tagal and A.marina. Alterations to mangrove community structure included: (1) reductions in stem density, stem diameter and basal area, (2) reductions in canopy cover (based on a photographic index of foliage projective cover) and (3) changes in relative abundance of species in mangrove zones. Recovery was observed in some stands but others had not recovered to prehail levels of canopy cover two years after the hailstorm. Recovery had occurred by regeneration of fresh leaves but no recruitment of young plants had been observed during the study. The forests in the impact area were dominated by either Ceriops tagal or Rhizophora stylosa with Avicennia marinaas a subdominant in places. C.tagal dominated forests within the impact area were relatively more severely affected (41.8% in the severe category) than R.stylosa dominated communities (only 17.4% in the severe category). This indicated that C.tagal dominated forests were more vulnerable to the effects of hail damage than R.stylosa dominated forests. In addition, hailimpacted C.tagal dominated forests represented a relatively high percentage of the area of C.tagal dominated forests in Port Curtis (44.3%). This percentage was much higher than hailimpacted R.stylosa dominated forests in Port Curtis (2.7%). These two factors – relatively severe impact on C.tagal communities and a relatively higher percentage affected within the Port Curtis area – illustrate that hailstorms, as a form of natural disturbance, are an important influence on the forest ecology of mangrove ecosystems in this region. 相似文献
7.
Fujimoto Kiyoshi Miyagi Toyohiko Kikuchi Takao Kawana Toshio 《Mangroves and Salt Marshes》1996,1(1):47-57
Mangrove habitats on Kosrae are divided into three types, i.e., an estuary or delta type, a backmarsh or lagoon type and a coral reef or tidal-flat type. Most of the mangrove forests of Kosrae have been developed during the last 2000 years by accumulating mangrove peat with the gradual sea-level rise of 1 to 2 mm/yr except the landward part of the estuary or delta type. On the other hand, during the period of rapid sea-level rise of about 10 mm/yr between 4100 and 3700 yr B.P., the mangrove forests ceased peat accumulation and retreated landward. Until 3500 yr B.P., mangrove forests were distributed only in narrow bands in the inlets. Therefore, the critical rate of mangrove peat accretion with sea-level rise is estimated at more than 2 mm/yr and less than 10 mm/yr. If the anticipated sea-level rise exceeds this critical rate, all of the mangrove forests of Kosrae will retreat landward and reduce rapidly. 相似文献
8.
雷州半岛红树林盐土的某些理化性质 总被引:3,自引:0,他引:3
红树林盐土是红树植被下的一类特殊土壤。雷州半岛红树林盐土各土层pH值为3.08 ~ 5.98,绝大多数低于4。土壤有机质平均含量为24.1 g/㎏,在土壤剖面中有机质含量分布没有规律性。土壤阳离子代换量为3.83 ~14.53 cmol/kg,平均6.94 cmo1/kg。土壤水溶性盐分7.6 ~ 42.1g/㎏,平均18.4 g/㎏,水溶性盐分有向下淋溶的趋势。土壤中<0.01 mm粒级含量一般>200 g/kg,土壤质地大多为中壤土类至中粘土类。 相似文献
9.
直接提取8个红树林土壤的总DNA,用放线菌门的特异性PCR引物进行扩增,通过构建16S rRNA文库,测序及系统发育分析,获取新颖放线菌菌株.结果发现,有酸微菌亚纲(Acidimicrobidae) (30.2%)、放线菌亚纲(Actinobacteridae) (68.0%)、红蝽菌亚纲(Coriobacteridae)(1.1%)和去腈基菌亚纲(Nitriliruptoridae)( 0.7%)成员,没有红色杆菌亚纲( Rubrobacteridae)成员.仙农指数和Chao1物种多样性指数(Schao1)表明,红树林土壤样品中含有丰富的放线菌多样性.以16S rDNA基因的相似率≥97%作为临界点,45.1%可能代表新候选种(candidate species)(未培养、分离).本研究为进一步获取新颖的红树林放线菌资源提供了基础. 相似文献
10.