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红树植物秋茄次生木质部生态解剖学的比较 总被引：4，自引：0，他引：4
本文研究了不同纬度秋茄（Ｋａｎｄｅｌｉａ ｃａｎｄｅｌ）次生木质部的组织结构及数量特征。秋茄的导管多为梯纹导管。随着纬度的升高,温度下降,各分布区导管分子长度和导管直径呈现下降的真挚深圳福田的秋茄导管分子长度、导管直径均是最大是个例外＿;穿孔板横隔的数目也纬度的升高而减少;盐度高（３３）造成福建云霄竹塔的秋茄低导管颁布频率、低单管孔率、低双管孔率;秋茄的射线分布频率随着纬度的升高而减少（海南东寨港 相似文献
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Mangrove forests are vulnerably threatened by sea level rise (SLR). Vegetation organic carbon (OC) stocks are important for mangrove ecosystem carbon cycle. It is critical to understand how SLR affects vegetation OC stocks for evaluating mangrove blue carbon budget and global climate change. In this study, biomass accumulation and OC stocks of mangrove vegetation were compared among three 10 year-old Kandelia obovata (a common species in China) mangrove forests under three intertidal elevations through species-specific allometric equations. This study simulated mangrove forests with SLR values of 0 cm, 40 cm and 80 cm, respectively, representing for the current, future ~100 a and future ~200 a SLR of mangrove forests along the Jiulong River Estuary, China. SLR directly decreased mangrove individual density and inhibited the growth of mangrove vegetation. The total vegetation biomasses were (12.86±0.95) kg/m2, (7.97±0.90) kg/m2 and (3.89±0.63) kg/m2 at Sites SLR 0 cm, SLR 40 cm and SLR 80 cm, respectively. The total vegetation OC stock decreased by approximately 3.85 kg/m2 (in terms of C) from Site SLR 0 cm to Site SLR 80 cm. Significantly lower vegetation biomass and OC stock of various components (stem, branch, leaf and root) were found at Site SLR 80 cm. Annual increments of vegetation biomass and OC stock also decreased with SLR increase. Moreover, significant lower sedimentation rate was found at Site SLR 80 cm. These indicated that SLR will decrease mangrove vegetation biomass and OC stock, which may reduce global blue carbon sink by mangroves, exacerbate global warming and give positive feedback to SLR. 相似文献
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闽江河口秋茄湿地土壤腐殖质组成及剖面分布特征 总被引：3，自引：0，他引：3
以闽江河口秋茄湿地土壤为研究对象,研究了土壤腐殖质组成和剖面分布特征,并探讨了土壤腐殖质组成与土壤理化因子的关系。结果表明,秋茄湿地土壤腐殖质的组成中,胡敏酸占有机碳变化范围为6%～18%,富里酸占有机碳变化范围为15%～34%,闽江河口秋茄湿地土壤为富里酸型土壤。土壤胡敏酸和胡敏素含量随深度增加而波动降低;富里酸表层的含量最低,中间层最高。表层的HA/FA最高,中间层最低。土壤理化性质中,pH值、有机碳含量、粘粒含量、氮含量与土壤腐殖质分布有显著线性相关关系。 相似文献
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The purpose of this study was to investigate the accumulation behavior of two typical PAHs,phenanthrene(PHE) and fluoranthene(FLA),uptaken by the mangrove Kandelia candel in various treated sandy soils.The experiment lasted for three months.Soil and plant samples were collected after 3,6,9 and 13 weeks of the incubation and the levels of PAHs were analyzed using a GC/MS(HP6890-5975B).The results showed that the root accumulations of PHE and FLA were elevated with the increase of the PAH concentrations in the soil.With prolonged exposure time,PHE and FLA concentrations of the roots increased significantly in comparison with the control.PHE and FLA concentrations of root after 13 weeks of treatment ranged from 0.28 to 4.36 μg·g-1 and 0.79 to 35.76 μg·g-1,respectively.The calculated mean values of the root concentration factors were 0.58 for PHE and 0.71 for FLA.This indicated that root accumulation of FLA was greater than PHE,which would result from the higher octanol-water partition coefficient(Kow) of FLA.These results underline the ability of mangroves to remove PAHs from contaminated marine substrates and hence their potential use in bioremediation and the removal of PAHs from the marine food chain. 相似文献
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本文研究红树植物外来种无瓣海桑对乡土种秋茄形态可塑性、生物量积累、生物量分配的影响。实验样地设在福建省漳州市漳浦县"东山湾滨海湿地互花米草防控与生态修复示范基地",共设置4种样地类型,秋茄种植间距为0.25 m×0.25 m(Ⅰ)的秋茄人工纯林、种植间距分别为0.5 m×0.5 m(Ⅱ)、1 m×1 m(Ⅲ)、2 m×2 m(Ⅳ)外来种无瓣海桑与秋茄(种植间距为25 cm×25 cm)人工混交林。结果表明:种植无瓣海桑,导致3种混交林样地秋茄的形态指标(H、D)、生物量(AGB、BGB、TB、R/S)在不同季节均表现出显著或极显著低于秋茄纯林对照样地;随着无瓣海桑种植间距的减小,秋茄形态指标、生物量也会发生显著的减小趋势;秋茄的形态特征、R/S、BGB与AGB之间均表现出极显著的异速生长关系,混交林的异速生长关系指数和决定系数均显著小于秋茄纯林,随着无瓣海桑种植间距的不断减小;BGB与AGB之间的斜率发生显著减小的趋势。说明:种植无瓣海桑在一定程度上导致秋茄明显发生个体发育漂变,并在一定程度上显著抑制秋茄的形态可塑性、生物量的积累、增长速率和分配格局。随着无瓣海桑种植间距的减小,在一定程度上,使秋茄个体发育漂变程度更加明显,对秋茄形态可塑性、生物量的积累、增长速率和分配格局的抑制作用显著加强。研究结果表明种植外来种无瓣海桑对乡土种秋茄具有一定程度的入侵倾向。 相似文献
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重金属Cu2+胁迫对红树植物秋茄幼苗生长及某些生理特性的影响 总被引：1，自引：0，他引：1
为揭示铜污染对红树植物的毒性效应和植物的抗性机制,作者研究了红树植物秋茄(Kandelia obovata)幼苗在不同质量浓度的Cu2+(0,0.5,5,50,100,200 mg/L)离子胁迫90 d后,幼苗生长、部分生理指标的变化以及Cu2+在幼苗体内的累积情况。测定的主要参数有:幼苗的主根长度、侧根数目、生物量、叶片的光合速率、色素含量、可溶性糖和蛋白含量及抗氧化酶系活性。研究结果表明:当Cu2+浓度范围在(0.5~200 mg/L)时,主根长度、侧根数目、生物量、叶片的光合速率、色素含量、可溶性糖和蛋白含量均呈降低趋势;根系POD活性持续升高,叶片和根系的SOD和CAT活性呈先升后降趋势;根系MDA含量在整个Cu2+胁迫浓度范围保持相对稳定,叶片MDA含量在高浓度Cu2+胁迫下增加;Cu2+主要累积在根部而向地上部分转运的较少。根据不同浓度的Cu2+离子对秋茄幼苗生长及生理特性影响,秋茄幼苗对Cu2+胁迫的耐受质量浓度范围为5~50 mg/L。 相似文献
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Influence of waterlogging time on the growth of Kandelia candel(L.) Druce seedlings grown for 70 d in the artificialtidal tanks‘ simulated semidiurnal tide under greenhouse is studied. Sand and soil act as the substrate and artificial seawater with salinity of 15 is used in cultivation. Shorter waterlogging time (inundated for about 2 ～ 4 h) promotes the growth of K candel seedlings, while longer time (inundated more than 8 h) or no waterlogging (0 h) inhibits their growth. The number and length of aerating roots increase with the increase of waterlogging time. Under existing conditions, the optimal waterlogging time for the growth of K. candel seedlings is about 2 ～ 4 h in every tide cycle. Compared with other treatments, the 2 h sanded treatments obtain the highest biomass of seedlings, have the lowest mass loss ofhypocotyl and broaden the photosynthetic area by increasing the area per leaf after 70-d cultivation. And the soil treatments have the similar tendency. However, waterlogging for 8h in every tide cycle is critical for normal development of seedlings.K. candel seedlings are highly tolerant to waterlogging and a proper waterlogging is beneficial to the growth of K. candel seedlings. 相似文献
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九龙江口秋茄和白骨壤的渗透调节剂及其贡献 总被引：9，自引：0，他引：9
于1994年和1995年,在福建省九龙江口龙海市海岸采集秋茄和白骨壤样品,采用原子吸收分光光度法、而定法和比色法分析了其叶片组织中无机和有机渗透调节剂的含量及其贡献。结果表明,秋茄和白骨壤的无机渗透调节剂在总渗透调节中的贡献分别为87.8％和87．4％,有机渗透调节剂的贡献仅分别为12．2％和12．6％。在无机渗透调节剂中,Na 和Cl-占主导地位,其次为K ,而Ca2 、Mg2 和NO3-的贡献很小。在有机渗透调节剂中,可溶性糖占主导地位,游离氨基酸和有机酸的贡献较小。另外,秋茄和白骨壤根据分析的无机和有机渗透调节剂浓度计算出的渗透调节能力均小于实测值,说明存在其它一些未知的渗透调节剂。 相似文献