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1.
Aboveground and belowground root biomasses (Babove and Broot) were measured for young, isolated Rhizophorastylosa on Iriomote Island, Japan. The relationship between these two parameters was significant and given as the equation, Broot(g dry weight) = 0.394 × Babove(g dry weight) – 485 (r = 0.986). Multiple regression analyses also revealed good correlation between diameter and biomass of prop roots (Dprop and Bprop) and between prop root and root biomasses. Consequently, root biomass could be estimated from the measurements of diameter and biomass of prop roots using the multiple regression equation, Broot(g dry weight) = 80.0 ×Dprop(cm) + 0.86 ×Bprop (g dry weight) – 251. The relationship between DBH (diameter at breast height) and prop root biomass was also adequately described using an allometric equation.In Hinchinbrook Channel, Australia, redox potential (measured as Eh) and organic carbon stocks in the top 5cm of mangrove sediments were measured along a 600m transect from the frequently inundated, Rhizophora dominated zone on the creek edge, towards higher grounds, where Ceriops spp. became increasingly dominant. Eh values were about –60mV near the creek edge and increased to 260mV on higher grounds. Organic carbon stocks showed an opposite trend to Eh, with the values decreasing from about 360tCha–1 to 160tCha–1. At 18 sites, representing six different habitats, organic carbon stocks were also measured along with the DBH of mangrove trees. DBH was converted into aboveground biomass and then into root biomass using the equations obtained in the study on Iriomote Island. The average organic carbon stocks in the top 50 cm of sediments, aboveground biomass and root biomass were 296tCha–1, 123 tCha–1 and 52 tCha–1, respectively, and accounted for 64%, 25% and 11% of the total organic carbon stock.  相似文献   
2.
The effectiveness of encasement and traditional techniques for planting red mangroves (Rhizophora mangle) in moderate to high wave energy environments was assessed. The three encasement types were the halflength PVC pipes, fulllength PVC pipes, and bamboo pipes. Plantings were conducted in August, 1997 at two locations in the Indian River Lagoon, Florida: Sebastian and Rocky Point. Furthermore, plantings were conducted in November, 1997 using fulllength encasements and conventional planting. Results indicate that seedlings planted within fulllength PVC encasements had the highest survivorship and growth because of their protection from waves and currents. Failure of seedlings within bamboo encasements seemed to be caused by insufficient light exposure. When comparing the two locations, a significantly greater growth was observed at the Sebastian location than at the Rocky Point location for the planting conducted in November, but not for those planted in August. No significant difference was observed in seedling survival when comparing those planted in August and November. However, there was a significantly greater growth in mangroves planted in August. With the exception of width of surf zone, there was no significant difference in the selected environmental parameters between the two locations.  相似文献   
3.
Background: Progress of forest production in response to the environment requires a quantitative understanding of leaf area development. Therefore, it is necessary to investigate the dynamics of seasonal crown foliage in order to understand the productivity of mangroves, which play an important role in the subtropical and tropical coastlines of the world. Method: Crown foliage dynamics of the mangrove Rhizophora styloso were studies to reveal patterns of leaf recruitment, survival and seasonal leaf area growth. Results: Flushing of leaves occurred throughout the year, but both flushing and leaf area growth pattern of leaves varied with season. Maximum flushing occurred in summer, but leaf areas did not differ significantly with season. The half-expansion period is longer, and the intrinsic rate of increase was lower in winter. Summer flushed leaves grew faster at their initial stage and reached their maximum area over a shorter period of time. The difference in temperature and air vapor pressure deficit (VPD) between summer and winter contributed to the present dynamics of foliage patterns. The mean leaf longevity was estimated to be 13.1 month. The crown foliage area was almost stable throughout the year. Conclusions: Homeostatic control of the crown foliage area may be accompanied by the existence of ecophysiological mechanisms in R. stylosa. Integrating crown foliage dynamics into forest models represents an important step towards incorporating physiological mechanisms into the models for predicting growth responses to environmental changes and for understanding the complex responses of tree growth and litter production.  相似文献   
4.
We report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico,with dominant vegetation of Red mangrove(Rhizophora mangle L.),Black mangrove(Avicennia germinans L.),white mangrove(Laguncularia racemosa Gaertn.)and button mangrove(Conocarpus erectus L.).We sampled soils with high fertility during the dry season in 2009 and 2010at three sites on Atasta Peninsula,Campeche.We used allometric equations to estimate above ground biomass(AGB)of trees.AGB was higher in C.erectus(253.18±32.17 t·ha-1),lower in A.germinans(161.93±12.63t·ha-1),and intermediate in R.mangle(181.70±16.58 t·ha-1)and L.racemosa(206.07±19.12 t·ha-1).Of the three studied sites,the highest absolute value for AGB was 279.72 t·ha-1in button mangrove forest at any single site.Carbon stored in soil at the three sites ranged from36.80±10.27 to 235.77±66.11 t·ha-1.The Tukey test(p0.05)made for AGB was higher for black mangrove showed significant differences in soil carbon content between black mangrove and button mangrove.C.erectus had higher AGB compared with the other species.A.germinans trees had lower AGB because they grew in hypersaline environments,which reduced their development.C.erectus grew on higher ground where soils were richer in nutrients.AGB tended to be low in areas near the sea and increased with distance from the coast.A.germinans usually grew on recently deposited sediments.We assumed that all sites have the same potential to store carbon in soil,and then we found that there were no significant differences in carbon content between the three samples sites:all sites had potential to store carbon for long periods.Carbon storage at the three sampling sites in the state of Campeche,Mexico,was higher than that reported for other locations.  相似文献   
5.
采用气相色谱—质谱联用分析法,分析测定红树植物红海榄胚轴中挥发油和脂肪酸的成分。结果表明,挥发油中分离出29个峰,鉴定出29种化合物,酚类物质有11种,是最多的一类,其总量达到了挥发油总量的47.12%。其中3-甲氧基-1,2-丙二醇含量最为丰富,占挥发油总量的26.39%;另外,还含有对甲基苯酚、橙花叔醇、榄香素等具有芳香气味的中药有效成分化合物。脂肪酸中分离出30个峰,鉴定出26种化合物,其中脂肪酸有8种,占脂肪酸总量的19.55%;十六酸(棕榈酸)、8,11,14-二十碳三烯酸、9,12-十八碳二烯酸(亚油酸)含量比较高,分别占脂肪酸总量的7.59%、4.25%、3.22%。  相似文献   
6.
Matthijs  S.  Tack  J.  van Speybroeck  D.  Koedam  N. 《Mangroves and Salt Marshes》1999,3(4):243-249
The relationship between soil redox state, sulphide concentration, salinity and spatial patterns of mangrove species distribution was investigated in the mangrove forest of Gazi Bay (Kenya). Field measurements were conducted to examine the relationship between species distribution along a band transect of 280m and soil redox potential (Eh) and sulphide patterns, as well as the indirectly related (through flooding regimes) soil salinity. Of the three major species Avicenniamarina, Ceriops tagal and Rhizophoramucronata present along the transect, only the distribution of the latter correlated with the measured soil variables, R. mucronata being absent from the lessreduced zone with high salinity. Bruguieragymnorhiza and Heritieralittoralis occur in minor populations, they are restricted to the saline, sulphidepoor and lessreduced substrates. From the results it is concluded that soil redox potential (Eh), sulphide concentration and salinity may contribute to structure mangroves through the distribution of dominant species, however in combination with other environmental conditions and processes of vegetation dynamics.  相似文献   
7.
Riley encased methodology (REM) was developed for the purpose of establishing mangroves along highenergy shorelines, revetments, and bulkheads where natural recruitment no longer occurs and where conventional planting methods are ineffective. The principles of REM include the processes of individual seedling isolation within tubular encasements and adaptation of the juvenile plant to the external environment of the restoration site. The success of REM results from specifications for encasement preparation, propagule or seedling selection, and positioning of both encasements and seedlings according to elevation and tidal regimes.  相似文献   
8.
转红树总DNA紫花苜蓿T1代耐盐株系的生理生化特性分析   总被引:1,自引:1,他引:0  
以花粉管通道法转红树总DNA紫花苜蓿阿尔冈金T1代耐盐植株幼苗为材料,经300 mmol/L NaCl处理后,测定叶绿素、脯氨酸、丙二醛含量和抗氧化酶活性等耐盐相关生理生化指标。结果显示,转基因株系叶绿素含量下降0.09~0.29倍,而对照植株下降0.32倍;转基因株系脯氨酸含量升高1.2~4.2倍,对照植株的脯氨酸升高0.9倍;转基因株系丙二醛含量升高0.15~0.29倍,对照植株的丙二醛含量升高0.36倍;转基因株系超氧化物歧化酶活性升高0.20~0.25倍,对照植株的超氧化物歧化酶活性升高0.19倍;转基因株系过氧化物酶和过氧化氢酶活性分别是对照的1.6~5.6倍和1.2~1.3倍。转基因株系表现出耐盐植物的生理生化特性。  相似文献   
9.
红树叶蛋白质样品制备方法的比较及其双向电泳分析   总被引:2,自引:0,他引:2  
采用水溶液提取法(磷酸盐缓冲液系统)、三氯乙酸-丙酮沉淀法和Phenol改良提取法,对红树叶进行蛋白质提取,并比较分析了这3种方法的蛋白质提取率、完整性、溶解性等。结果表明:水溶液提取法得到的是胶状沉淀,基本为多糖类物质,蛋白质含量很低;三氯乙酸-丙酮沉淀法提取的蛋白质纯度较高,但双向电泳背景最低,提取率较低,蛋白质的完整性差;Phenol改良提取法的蛋白质提取率高,约为三氯乙酸-丙酮法的10倍,双向电泳凝胶背景比三氯乙酸-丙酮沉淀法要深,蛋白质的完整性好,能够被电泳分离的蛋白质点是三氯乙酸-丙酮沉淀法的7倍左右。Phenol改良提取法在蛋白质的提取率以及完整性方面远远高于其他2种蛋白质提取方法。  相似文献   
10.
红海榄赤斑病病原菌鉴定及其生物学特性研究   总被引:6,自引:0,他引:6  
 本文对来自红海榄(Rhizophora stylosa)赤斑病同一病斑上获得的2个菌株PⅠ-1和PⅡ-3进行了鉴定和生物学特性研究。结果表明,PⅡ-3菌株的致病力比PⅠ-1的稍强;2个菌株均具有一定的寄主专化性。经形态特征观察与rDNA-ITS序列分析,2个菌株均鉴定为异色拟盘多毛孢(Pestalotiopsis versicolor)。生物学特性测定结果表明,温度、pH值和光照对2个菌株菌丝生长及孢子萌发的影响差异不大,生长温度均为10~32℃(最适25℃),pH值为3.0~10.9(最适4.0);孢子萌发温度均为10~35℃(最适25~28℃),pH值为2.5~8.0(最适3.0);黑暗条件有利于2个菌株菌丝生长和孢子萌发。但2个菌株的产孢特性存在明显差异,其中PⅠ-1产孢的最适温度为28℃而PⅡ-3为20℃;PⅠ-1产孢的最适pH值为5.1而PⅡ-3为9.0;PⅠ-1产孢对光照不敏感,而PⅡ-3在黑暗条件下几乎不产孢。另外,在相似条件下,PⅠ-1产孢量比PⅡ-3大,而PⅡ-3菌丝生长速度比PⅠ-1快,孢子萌发率也比PⅠ-1高。由此可见,2个菌株PⅠ-1和PⅡ-3虽属于同一个种,但某些生物学特性存在一定的差异。  相似文献   
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