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Fulltext Plant species- and stage-specific differences in microbial decay of mangrove leaf litter: the older the better?

Pradisty NA, Amir AA, Zimmer M

Oecologia, 2021 Apr;195(4):843-858.
PMID: 33559746 DOI: 10.1007/s00442-021-04865-3

Leaf litter and its breakdown products represent an important input of organic matter and nutrients to mangrove sediments and adjacent coastal ecosystems. It is commonly assumed that old-grown stands with mature trees contribute more to the permanent sediment organic matter pool than younger stands. However, neither are interspecific differences in leaf decay rates taken into account in this assumption nor is our understanding of the underlying mechanisms or drivers of differences in leaf chemistry sufficient. This study examines the influence of different plant species and ontogenetic stage on the microbial decay of mangrove leaf litter. A litterbag experiment was conducted in the Matang Mangrove Forest Reserve, Malaysia, to monitor leaf litter mass loss, and changes in leaf litter chemistry and microbial enzyme activity. Four mangrove species of different morphologies were selected, namely the trees Rhizophora apiculata and Bruguiera parviflora, the fern Acrostichum aureum and the shrub Acanthus ilicifolius. Decay rates of mangrove leaf litter decreased from A. ilicifolius to R. apiculata to B. parviflora to A. aureum. Leaf litter mass, total phenolic content, protein precipitation capacity and phenol oxidase activity were found to decline rapidly during the early stage of decay. Leaf litter from immature plants differed from that of mature plants in total phenolic content, phenolic signature, protein precipitating capacity and protease activity. For R. apiculata, but not of the other species, leaf litter from immature plants decayed faster than the litter of mature plants. The findings of this study advance our understanding of the organic matter dynamics in mangrove stands of different compositions and ages and will, thus, prove useful in mangrove forest management.

Matched MeSH terms: Rhizophoraceae*
Fulltext Genetic differentiation and phylogeography of partially sympatric species complex Rhizophora mucronata Lam. and R. stylosa Griff. using SSR markers

Wee AK, Takayama K, Chua JL, Asakawa T, Meenakshisundaram SH, Onrizal, et al.

BMC Evol. Biol., 2015 Mar 29;15:57.
PMID: 25888261 DOI: 10.1186/s12862-015-0331-3

BACKGROUND: Mangrove forests are ecologically important but globally threatened intertidal plant communities. Effective mangrove conservation requires the determination of species identity, management units, and genetic structure. Here, we investigate the genetic distinctiveness and genetic structure of an iconic but yet taxonomically confusing species complex Rhizophora mucronata and R. stylosa across their distributional range, by employing a suite of 20 informative nuclear SSR markers.
RESULTS: Our results demonstrated the general genetic distinctiveness of R. mucronata and R. stylosa, and potential hybridization or introgression between them. We investigated the population genetics of each species without the putative hybrids, and found strong genetic structure between oceanic regions in both R. mucronata and R. stylosa. In R. mucronata, a strong divergence was detected between populations from the Indian Ocean region (Indian Ocean and Andaman Sea) and the Pacific Ocean region (Malacca Strait, South China Sea and Northwest Pacific Ocean). In R. stylosa, the genetic break was located more eastward, between populations from South and East China Sea and populations from the Southwest Pacific Ocean. The location of these genetic breaks coincided with the boundaries of oceanic currents, thus suggesting that oceanic circulation patterns might have acted as a cryptic barrier to gene flow.
CONCLUSIONS: Our findings have important implications on the conservation of mangroves, especially relating to replanting efforts and the definition of evolutionary significant units in Rhizophora species. We outlined the genetic structure and identified geographical areas that require further investigations for both R. mucronata and R. stylosa. These results serve as the foundation for the conservation genetics of R. mucronata and R. stylosa and highlighted the need to recognize the genetic distinctiveness of closely-related species, determine their respective genetic structure, and avoid artificially promoting hybridization in mangrove restoration programmes.

Matched MeSH terms: Rhizophoraceae/classification*; Rhizophoraceae/genetics*
Four decades of data indicate that planted mangroves stored up to 75% of the carbon stocks found in intact mature stands

Bourgeois CF, MacKenzie RA, Sharma S, Bhomia RK, Johnson NG, Rovai AS, et al.

Sci Adv, 2024 Jul 05;10(27):eadk5430.
PMID: 38968357 DOI: 10.1126/sciadv.adk5430

Mangroves' ability to store carbon (C) has long been recognized, but little is known about whether planted mangroves can store C as efficiently as naturally established (i.e., intact) stands and in which time frame. Through Bayesian logistic models compiled from 40 years of data and built from 684 planted mangrove stands worldwide, we found that biomass C stock culminated at 71 to 73% to that of intact stands ~20 years after planting. Furthermore, prioritizing mixed-species planting including Rhizophora spp. would maximize C accumulation within the biomass compared to monospecific planting. Despite a 25% increase in the first 5 years following planting, no notable change was observed in the soil C stocks thereafter, which remains at a constant value of 75% to that of intact soil C stock, suggesting that planting effectively prevents further C losses due to land use change. These results have strong implications for mangrove restoration planning and serve as a baseline for future C buildup assessments.

Matched MeSH terms: Rhizophoraceae/growth & development; Rhizophoraceae/metabolism
Fulltext Mangroves give cause for conservation optimism, for now

Friess DA, Yando ES, Abuchahla GMO, Adams JB, Cannicci S, Canty SWJ, et al.

Curr Biol, 2020 02 24;30(4):R153-R154.
PMID: 32097637 DOI: 10.1016/j.cub.2019.12.054

Friess et al. discuss the results of conservation efforts for mangrove forests in recent years.

Matched MeSH terms: Rhizophoraceae*
Correlations between allocation to foliar phosphorus fractions and maintenance of photosynthetic integrity in six mangrove populations as affected by chilling

Yan L, Sunoj VSJ, Short AW, Lambers H, Elsheery NI, Kajita T, et al.

New Phytol, 2021 12;232(6):2267-2282.
PMID: 34610157 DOI: 10.1111/nph.17770

Chilling restrains the distribution of mangroves. We tested whether foliar phosphorus (P) fractions and gene expression are associated with cold tolerance in mangrove species. We exposed seedlings of six mangrove populations from different latitudes to favorable, chilling and recovery treatments, and measured their foliar P concentrations and fractions, photochemistry, nighttime respiration, and gene expression. A Kandelia obovata (KO; 26.45°N) population completely and a Bruguiera gymnorhiza (Guangxi) (BGG; 21.50°N) population partially (30%) survived chilling. Avicennia marina (24.29°N), and other B. gymnorhiza (26.66°N, 24.40°N, and 19.62°N) populations died after chilling. Photosystems of KO and photosystem I of BGG were least injured. During chilling, leaf P fractions, except nucleic acid P in three populations, declined and photoinhibition and nighttime respiration increased in all populations, with the greatest impact in B. gymnorhiza. Leaf nucleic acid P was positively correlated with photochemical efficiency during recovery and nighttime respiration across populations for each treatment. Relatively high concentrations of nucleic acid P and metabolite P were associated with stronger chilling tolerance in KO. Bruguiera gymnorhiza exhibited relatively low concentrations of organic P in favorable and chilling conditions, but its partially survived population showed stronger compensation in nucleic acid P and Pi concentrations and gene expression during recovery.

Matched MeSH terms: Rhizophoraceae*
Measurement of mass attenuation coefficients of Rhizophora spp. binderless particleboards in the 16.59-25.26 keV photon energy range and their density profile using x-ray computed tomography

Marashdeh MW, Bauk S, Tajuddin AA, Hashim R

Appl Radiat Isot, 2012 Apr;70(4):656-62.
PMID: 22304963 DOI: 10.1016/j.apradiso.2012.01.008

The mass attenuation coefficients of Rhizophora spp. binderless particleboard with four different particle sizes (samples A, B, C and D) and natural raw Rhizophora spp. wood (sample E) were determined using single-beam photon transmission in the energy range between 16.59 and 25.26 keV. This was done by determining the attenuation of K(α1) X-ray fluorescent (XRF) photons from niobium, molybdenum, palladium, silver and tin targets. The results were compared with theoretical values of young-age breast (Breast 1) and water calculated using a XCOM computer program. It was found that the mass attenuation coefficient of Rhizophora spp. binderless particleboards to be close to the calculated XCOM values in water than natural Rhizophora spp. wood. Computed tomography (CT) scans were then used to determine the density profile of the samples. The CT scan results showed that the Rhizophora spp. binderless particleboard has uniform density compared to natural Rhizophora spp. wood. In general, the differences in the variability of the profile density decrease as the particle size of the pellet samples decreases.

Matched MeSH terms: Rhizophoraceae*
The value of small mangrove patches

Curnick DJ, Pettorelli N, Amir AA, Balke T, Barbier EB, Crooks S, et al.

Science, 2019 01 18;363(6424):239.
PMID: 30655434 DOI: 10.1126/science.aaw0809
Matched MeSH terms: Rhizophoraceae*
Accumulation and distribution of lead and copper in Avicennia Marina and Rhizophora Apiculata from Balok mangrove forest, Pahang, Malaysia

Rina Sharlinda M, Kamaruzzaman B, Akbar John B, Siti Waznah A

Sains Malaysiana, 2011;40:1179-1186.

Bioaccumulation of lead and Copper in Avicennia marina and Rhizophora apiculata was studied. Samples of leaves, barks and roots were collected from Balok mangrove forest, Pahang. Pb and Cu accumulation was higher in Avicennia marina root tissue compared to bark and leaf but lower than surrounding sediment level. The average concentration of Pb in A. marina leaf, bark, root and sediment was observed to be 5.39 ppm, 3.63 ppm, 18.21 ppm and 23.13 ppm, and average Cu concentration was 4.13 ppm, 4.27 ppm, 4.81 ppm and 12.33 ppm, respectively. R. apiculata also showed higher concentration of Pb and Cu in root tissue compared to bark and leaf tissues but lower than surrounding sediment. The average concentration of Pb in R. apiculata leaf, bark, root and sediment was observed to be 4.30 ppm, 2.97 ppm, 22.45 ppm and 31.23 ppm, respectively. The average Cu concentration was 2.93 ppm, 4.71 ppm, 4.81 ppm and 15.52 ppm, respectively. Results of concentration factors (CF) showed that the accumulation of Pb and Cu was higher in A. marina than in R. apiculata.

Matched MeSH terms: Rhizophoraceae
Mass attenuation coefficients of natural Rhizophora spp. wood for X-rays in the 15.77-25.27 keV range

Shakhreet BZ, Bauk S, Tajuddin AA, Shukri A

Radiat Prot Dosimetry, 2009 Jul;135(1):47-53.
PMID: 19482883 DOI: 10.1093/rpd/ncp096

The mass attenuation coefficients (mu/rho) of Rhizophora spp. were determined for photons in the energy range of 15.77-25.27 keV. This was carried out by studying the attenuation of X-ray fluorescent photons from zirconium, molybdenum, palladium, silver, indium and tin targets. The results were compared with theoretical values for average breast tissues in young-age, middle-age and old-age groups calculated using photon cross section database (XCOM), the well-known code for calculating attenuation coefficients and interaction cross-sections. The measured mass attenuation coefficients were found to be very close to the calculated XCOM values in breasts of young-age group.

Matched MeSH terms: Rhizophoraceae/chemistry*
A new diglycosyl megastigmane from Carallia brachiata

Ling SK, Takashima T, Tanaka T, Fujioka T, Mihashi K, Kouno I

Fitoterapia, 2004 Dec;75(7-8):785-8.
PMID: 15567266

A new megastigmane diglycoside was isolated from the leaves of Carallia brachiata. The structure was determined by spectroscopic methods as 3-hydroxy-5,6-epoxy-beta-ionol -3-O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside (1). Additionally, 29 known compounds consisting of two megastigmanes, one 1,2-dithiolane derivative, seven aromatic compounds, five condensed tannins, 12 flavonoids, and two glyceroglycolipids were isolated and identified.

Matched MeSH terms: Rhizophoraceae*
Fulltext Low genetic diversity indicating the threatened status of Rhizophora apiculata (Rhizophoraceae) in Malaysia: declined evolution meets habitat destruction

Azman A, Ng KK, Ng CH, Lee CT, Tnah LH, Zakaria NF, et al.

Sci Rep, 2020 11 05;10(1):19112.
PMID: 33154411 DOI: 10.1038/s41598-020-76092-4

Worldwide, many mangrove species are experiencing significant population declines, including Rhizophora apiculata, which is one of the most widespread and economically important species in tropical Asia. In Malaysia, there has been an alarming decline in R. apiculata populations driven primarily by anthropogenic activities. However, the lack of genetic and demographic information on this species has hampered local efforts to conserve it. To address these gaps, we generated novel genetic information for R. apiculata, based on 1,120 samples collected from 39 natural populations in Peninsular Malaysia. We investigated its genetic diversity and genetic structure with 19 transcriptome and three nuclear microsatellite markers. Our analyses revealed a low genetic diversity (mean He: 0.352) with significant genetic differentiation (FST: 0.315) among populations of R. apiculata. Approximately two-third of the populations showed significant excess of homozygotes, indicating persistent inbreeding which might be due to the decrease in population size or fragmentation. From the cluster analyses, the populations investigated were divided into two distinct clusters, comprising the west and east coasts of Peninsular Malaysia. The western cluster was further divided into two sub-clusters with one of the sub-clusters showing strong admixture pattern that harbours high levels of genetic diversity, thus deserving high priority for conservation.

Matched MeSH terms: Rhizophoraceae/genetics*
Fulltext Treated Rhizophora mucronata tannin as a corrosion inhibitor in chloride solution

Agi A, Junin R, Rasol M, Gbadamosi A, Gunaji R

PLoS One, 2018;13(8):e0200595.
PMID: 30089104 DOI: 10.1371/journal.pone.0200595

Treated Rhizopora mucronata tannin (RMT) as a corrosion inhibitor for carbon steel and copper in oil and gas facilities was investigated. Corrosion rate of carbon-steel and copper in 3wt% NaCl solution by RMT was studied using chemical (weight loss method) and spectroscopic (FTIR) techniques at various temperatures in the ranges of 26-90°C. The weight loss data was compared to the electrochemical by the application of Faraday's law for the conversion of corrosion rate data from one system to another. The inhibitive efficiency of RMT was compared with commercial inhibitor sodium benzotriazole (BTA-S). The best concentration of RMT was 20% (w/v), increase in concentration of RMT decreased the corrosion rate and increased the inhibitive efficiency. Increase in temperature increased the corrosion rate and decreased the inhibitive efficiency but, the rate of corrosion was mild with RMT. The FTIR result shows the presence of hydroxyl group, aromatic group, esters and the substituted benzene group indicating the purity of the tannin. The trend of RMT was similar to that of BTA-S, but its inhibitive efficiency for carbon-steel was poor (6%) compared to RMT (59%). BTA-S was efficient for copper (76%) compared to RMT (74%) at 40% (w/v) and 20% (w/v) concentration respectively. RMT was efficient even at low concentration therefore, the use of RMT as a cost effective and environmentally friendly corrosion inhibiting agent for carbon steel and copper is herein proposed.

Matched MeSH terms: Rhizophoraceae/metabolism*
A coastal vegetation survey of Pahang, Malaysia

Rozainah M

Sains Malaysiana, 2006;35:55-62.

A survey on coastal vegetation of Pahang in some localities from Sg. Balok in Kuantan southwards to Kuala Endau in Rompin was conducted from middle 2004 to early 2005. A total of 88 species of plants were recorded and identified mostly to the generic or species level. The usual vegetation types were sand and mudflat beach vegetations like Pandanus odoratissimus, Ipomoea pes capre and Casuarina equisetifolia and mangrove vegetation like Sonneratia caseolaris, Rhizophora mucronata and Avicennia marina. This paper also reports some unique heath-type forest vegetation like Hopea spp. in Menchali area.

Matched MeSH terms: Rhizophoraceae
Usaha penanaman semula pokok paya bakau: kajian ke atas Bruguiera cylindrica di Pulau Carey, Selangor

Arbain Mokhtar, Azniza Abdul Ghani, Rozainah MZ

Sains Malaysiana, 2009;38.

Penanaman semula hutan paya bakau dipertimbangkan sebagai satu usaha terbaik bagi melindungi dan memelihara kawasan pesisir pantai. Dalam kajian ini sejumlah 180 anak benih Bruguiera cylindrica telah ditanam di kawasan pesisir pantai Pulau Carey. Dua set eksperimen daripada segi corak dan medium dilakukan dengan 3 plot replika bagi setiap rawatan dengan kaedah Blok Rawak Lengkap. Kadar keterushidupan anak bakau B. cylindrica dicatat setiap 2 minggu selama 20 minggu. Keputusan menunjukkan corak penanaman secara kelompok adalah lebih sesuai (20%). Anak bakau yang ditanam secara langsung di atas tanah menunjukkan kadar hidup yang lebih tinggi (30%). Namun ujian analisis ANOVA menunjukkan tiada perbezaan yang signifikan antara ketiga-tiga corak taburan penanaman dan penggunaan medium yang berbeza ini terhadap keterushidupan anak bakau B. cylindrica.

Matched MeSH terms: Rhizophoraceae
Fulltext Isolation and expression analysis of novel silicon absorption gene from roots of mangrove (Rhizophora apiculata) via suppression subtractive hybridization

Sahebi M, Hanafi MM, Abdullah SN, Rafii MY, Azizi P, Nejat N, et al.

Biomed Res Int, 2014;2014:971985.
PMID: 24516858 DOI: 10.1155/2014/971985

Silicon (Si) is the second most abundant element in soil after oxygen. It is not an essential element for plant growth and formation but plays an important role in increasing plant tolerance towards different kinds of abiotic and biotic stresses. The molecular mechanism of Si absorption and accumulation may differ between plants, such as monocotyledons and dicotyledons. Silicon absorption and accumulation in mangrove plants are affected indirectly by some proteins rich in serine and proline amino acids. The expression level of the genes responsible for Si absorption varies in different parts of plants. In this study, Si is mainly observed in the epidermal roots' cell walls of mangrove plants compared to other parts. The present work was carried out to discover further information on Si stress responsive genes in Rhizophora apiculata, using the suppression subtractive hybridization technique. To construct the cDNA library, two-month-old seedlings were exposed to 0.5, 1, and 1.5 mM SiO2 for 15 hrs and for 1 to 6 days resulting in a total of 360 high quality ESTs gained. Further examination by RT-PCR and real-time qRT-PCR showed the expression of a candidate gene of serine-rich protein.

Matched MeSH terms: Rhizophoraceae/genetics*; Rhizophoraceae/metabolism*
Serine-rich protein is a novel positive regulator for silicon accumulation in mangrove

Sahebi M, Hanafi MM, Siti Nor Akmar A, Rafii MY, Azizi P, Idris AS

Gene, 2015 Feb 10;556(2):170-81.
PMID: 25479011 DOI: 10.1016/j.gene.2014.11.055

Silicon (Si) plays an important role in reducing plant susceptibility against a variety of different biotic and abiotic stresses; and also has an important regulatory role in soil to avoid heavy metal toxicity and providing suitable growing conditions for plants. A full-length cDNAs of 696bp of serine-rich protein was cloned from mangrove plant (Rhizophora apiculata) by amplification of cDNA ends from an expressed sequence tag homologous to groundnut (Arachis hypogaea), submitted to NCBI (KF211374). This serine-rich protein gene encodes a deduced protein of 223 amino acids. The transcript titre of the serine-rich protein was found to be strongly enriched in roots compared with the leaves of two month old mangrove plants and expression level of this serine-rich protein was found to be strongly induced when the mangrove seedlings were exposed to SiO2. Expression of the serine-rich protein transgenic was detected in transgenic Arabidopsis thaliana, where the amount of serine increased from 1.02 to 37.8mg/g. The same trend was also seen in Si content in the roots (14.3%) and leaves (7.4%) of the transgenic A. thaliana compared to the wild-type plants under Si treatment. The biological results demonstrated that the accumulation of the serine amino acid in the vegetative tissues of the transgenic plants enhanced their ability to absorb and accumulate more Si in the roots and leaves and suggests that the serine-rich protein gene has potential for use in genetic engineering of different stress tolerance characteristics.

Matched MeSH terms: Rhizophoraceae/genetics; Rhizophoraceae/metabolism*
Fulltext Bioadsorption of multiple heavy metal ions by rhizophora apiculate sp. and elaesis guineensis sp.

Nicodemus Ujih, M.B., Mohammad Isa Mohamadin, Millaa Armila Asli, Bebe Norlita Mohamed

Scientific Research Journal, 2017;14(1):15-27.
MyJurnal

Heavy metal ions contamination has become more serious which is caused
by the releasing of toxic waterfrom industrial area and landfill that are very
harmful to all living organism especially human and can even cause death
if contaminated in small amount of heavy metal concentration. Currently,
peoples are using classic method namely electrochemical treatment,
chemical oxidation/reduction, chemical precipitation and reverse osmosis
to eliminate the metal ions from toxic water. Unfortunately, these methods
are costly and not environmentally friendly as compared to bioadsorption
method, where agricultural waste is used as biosorbent to remove heavy
metals. Two types of agricultural waste used in this research namely oil
palm mesocarp fiber (Elaesis guineensis sp.) (OPMF) and mangrove bark
(Rhizophora apiculate sp.) (MB) biomass. Through chemical treatment,
the removal efficiency was found to improve. The removal efficiency is
examined based on four specification namely dosage, of biosorbent to
adsorb fourtypes of metalsion explicitly nickel, lead, copper, and chromium.
The research has found that the removal efficiency of MB was lower than
OPMF; whereas, the multiple metals ions removal efficiency decreased in
the order of Pb2+ > Cu2+ > Ni2+ > Cr2+.

Matched MeSH terms: Rhizophoraceae
Fulltext Dosimetric study of Rhizophora Spp. particle board using Gafchromic XRQA2 film

A. N. Azahari, N. D.M Yusob, H.A. Saidun, N.K.Y Ali, R. Abdullah, R. Hashim, et al.

Malaysian Journal of Medicine and Health Sciences, 2020;16(102):46-50.
MyJurnal

Introduction: Various phantom with varied materials has been proposed to replace the human body. Besides, there is always a demand to use the local material as a phantom material, which is readily available and inexpensive. Wood is usually preferred because it is multifunction, environmentally friendly, low in toxic, inexpensive, as well as easy to use and prepare. Previous studies have found that Rhizophora spp. is a suitable natural source material and has been suggested due to its comparable dosimetric properties to commercial phantom. Methods: In this study, fabricated Rhizophora spp. particleboards phantom was opted as a solid-equivalent phantom medium at low energy photon beams using Gafchromic film x-ray quality assurance 2 (XRQA2). Additionally, the characteristics of XRQA2 film in the diagnostic energy range were generated. Results: Interestingly, the density of the fabricated Rhizophora spp particleboards was observed to have the same density with the water equivalent material (ρ= 1.00 g.cm-3) and has shown to have loosened agreement with PDD of water phantom at approximately 25% of the dose error. Also, further analysis using XRQA 2 film showed that energy was independent at different ranges. Conclusion: The analysis of fabricated Rhizophora spp particleboards undertaken here has extended our knowledge of the possibility of man- ufacturing cost-effective water equivalent phantom by using binder-less particleboard from Rhizophora spp. There- fore, a definite need for smaller interspacing particles should be considered to elevate the potential of Rhizophora spp particle boards as water equivalent materials.

Matched MeSH terms: Rhizophoraceae
Possible food sources of macrozoobenthos in the manko mangrove ecosystem, okinawa (Japan): a stable isotope analysis approach

Wardiatno Y, Mardiansyah, Prartono T, Tsuchiya M

Trop Life Sci Res, 2015 Apr;26(1):53-65.
PMID: 26019747

Identifying potential food sources in mangrove ecosystems is complex because of the multifarious inputs from both land and sea. This study, which was conducted in the Manko mangrove ecosystem of Okinawa, Japan, determined the composition of the stable isotopes δ(13)C and δ(15)N in primary producers and macrozoobenthos to estimate the potential food sources assimilated and to elucidate the target trophic levels of the macrozoobenthos. We measured the two stable isotope signatures of three gastropods (Cerithidea sp., Cassidula mustelina, Peronia verruculata), two crabs (Grapsidae sp., Uca sp.), mangrove tree (Kandelia candel) leaves, and sediment from the mangrove ecosystem. The respective carbon and nitrogen isotope signature results were as follows: -22.4‰ and 8.6‰ for Cerithidea sp., -25.06‰ and 8‰ for C. mustelina, -22.58‰ and 8‰ for P. verruculata, -24.3‰ and 10.6‰ for unidentified Grapsidae, -21.87 ‰ and 11.5 ‰ for Uca sp., -29.81‰ and 11‰ for K. candel, and -24.23‰ and 7.2‰ for the sediment. The stable isotope assimilation signatures of the macrozoobenthos indicated sediment as their food source. Considering the trophic levels, the stable isotope values may also indicate that the five macrozoobenthos species were secondary or higher consumers.

Matched MeSH terms: Rhizophoraceae
Fulltext Attenuation coefficients of Rhizophora spp. in the 11.22 to 28.43 keV photon energy range

Sabar Bauk, Abd. Aziz Tajuddin

Journal of Nuclear and Related Technologies, 2008;2008(1):11-19.
MyJurnal

The linear and the mass attenuation coefficients of Rhizophora spp. wood in the photon energy range of 11.22 - 28.43 keV were determined. This was done by studying the attenuation of x-ray fluorescent (XRF) photons from selenium, molybdenum, silver and tin targets. Both the Kα and Kβ peaks were utilised. The results were compared with theoretical values for average breast tissues for youngage, middle-age and old-age groups calculated by using a XCOM computer programme. The mass attenuation coefficient of Rhizophora spp. was found to be close to that of the calculated young-age breast in this photon energy range.

Matched MeSH terms: Rhizophoraceae

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