Annual Ring Structure Research Articles

Towards a method for determining the age of chum salmon

The purpose of the work is to perform a quantitative comparative analysis of the structure and size of annual rings of chum salmon scales to prepare a methodological manual for determining age. The research material included scale preparations from 493 chum salmon producers of different ages, on which sclerites were counted and the diameter of annual rings was measured.Methods used: comparative data analysis, descriptive statistics methods.Results: it was found that the size of the scales, the size of each of the annual rings, as well as the number of sclerites in the annual rings of male and female chum salmon within each age group do not differ. The number of sclerites forming each annual ring, as well as the radius of the rings, varies significantly among different individuals. With age, as the length and mass of fish increase, the size of the scales naturally increases. Moreover, an acceleration in the growth rate is observed during the year preceding puberty. As a result, the number of sclerites in the last annual ring, as well as the size of this ring in fish that reach sexual maturity is always greater than in fish of the same age, but remaining in the sea to continue feeding.Practical significance: the presented article is a scientific accompaniment of a methodological manual for the practical determination of the age of chum salmon by scales.

Elasto-plastic material model of green beech wood

Physically modelling the mechanical response of a tree by numerical simulation depends on having accurate data on the mechanical properties of green hardwood. Lacking such data, we developed and validated an orthotropic elasto-plastic (E–P) material model, based on the results of experiments performed on European beech (Fagus sylvatica L.) green wood, capable of including both the non-linearity and orthotropic properties of the material. We selected 655 clear samples with the special orthotropic structure of annual rings. All samples were prepared immediately after felling; their moisture content (MC) was 80% on average. The mechanical responses in normal directions and shear are represented by bi-linear stress–strain curves. The E–P model was validated by comparing the force–deflection response of three-point bending of green wood samples in a finite-element method (FEM) simulation (the average relative error was 4.6% for point-wise and 1.7% for integral-wise comparison). The output of this work was a consistent set of material constants for the E–P material model that is now available for the structural analysis of beech wood with MC above to fibre saturation point (FSP), especially green wood, subjected to relatively high loads (such that a plastic deformation appears) and that can very well predict a non-linear response above the proportional limits.

The influence of road traffic and industrial plant-induced air pollution on the physical, mechanical, chemical and morphological properties of the black pine wood

Road traffic pollution and industrial plant-induced pollution affect negatively the development of forest trees. How forest trees are affected by their growing environment is important for sustainable environment. The study aimed to investigate the physical, mechanical, chemical, and morphological properties of the Pinus nigra (black pine) tree which grows under different conditions. Tree samples were chosen from three different lands where were inside the forest (O), near the roadside (Y), and near the factory (F). It was studied whether there were any significant differences among the “O”, “Y” and “F” in terms of their wood properties such as physical, mechanical, chemical, and morphological. As a result, the “O” samples demonstrated more regular annual ring structure. On the other hand, it was observed that the “Y” samples had longer and wider tracheid cells. In addition, “Y” samples had better mechanical strength than “O” and “F”. Environmental pollution caused the presence of some different elements (chlorine and iron) in “Y” and “F”. As a result, it was determined that the trees growing near the roadside or near industrial plants have significant differences from forest trees which are far away from pollutions. It is possible to say that Pinus nigra (black pine) is resistant to environmental stress. For this reason, it can be recommended to use it as a barrier to reduce air pollution on the roadsides.

Analysis of anomalies in the structure and size of annual rings in mossy and ledum pine forests

Analysis of anomalies in the structure and size of annual rings in mossy and ledum pine forests

Trends in radial growth of Scott pine trees in geographical crops

The purpose of the research is to identify trends in the change in radial growth, the width and structure of annual rings in forest-steppe and steppe pine ecotypes in 59-61-year-old geographical cultures. To achieve the intended goal, according to the methodology adopted in forest inventory, 32 trial plots were laid, on which the diameter of trees at a height of 1.3 m with an accuracy of 0.1 cm and the height with a Blume-Leiss altimeter with an accuracy of 0.1 m were measured with a measuring fork. area (PP) from 3 trees of average diameter and height, radial wood cores were taken with a Haglof-60 age borer at a height of 1.3 m. After dating the growth rings of wood, their width was measured at the Lintab-6 complex, divided into early and late. The obtained data were statistically processed using the programs Statistica 8.2 and Excel-10. In the forest-steppe and steppe ecotypes, the trends of radial growth were determined and their features with age were revealed. So, up to 10 years it increases, then sharply decreases and after 20 years it stabilizes.

Graphene-based aerogel microspheres with annual ring-like structures for broadband electromagnetic attenuation

Graphene aerogels have attracted extensive attention in electromagnetic protection due to lightweight and efficient microwave absorbing properties, but until now the design of its shape and structure is still a research hotspot. Herein, reduced graphene aerogel microspheres (CSA-RGO AMs) with annual ring structure with regular interlayer spacing are synthesized by wet spinning-chemical reduction-lyophilization. Due to the special chiral helical structure and electromagnetic cross-polarization, the impedance matching and attenuation ability of microspheres to electromagnetic waves are enhanced. The CSA-RGO AMs at a low load of 4 wt% can achieve the minimum reflection loss (RLmin) of − 63 dB with a thickness of 3.6 mm, and the effective absorption bandwidth (EAB) reaches 7.04 GHz. On this basis, we further obtain polyaniline@reduced graphene oxide microspheres (PANi@RGO AMs) with the same chiral helical structure through in-situ doping polymerization of polyaniline. Heterogeneous interfaces bring the interface polarization and enhance the reflection and scattering of electromagnetic waves. And the corresponding RLmin can reach − 48 dB when the thickness is only 2.8 mm, and the EAB remains 6.88 GHz. Therefore, the new strategy for constructing chiral structures proposed in this study provides a new idea for realizing high-performance electromagnetic wave absorption of graphene-based aerogel absorbers.

Spatial variation of eucalyptus fibres considering the structure of annual growth rings

Background: The fibres dimensions vary along a tree trunk, and these variations are related to the apical meristem and vascular cambium activities; understanding these variations would guide the best use of wood. There have been studies on the pattern of fibres dimensions variation along the tree trunk in the radial and longitudinal directions; however, the vast majority do not take into account the structure of the annual growth rings. Hence, this study aimed to obtain the pattern of fibres dimensions variation and their quality indexes along the tree trunk take into account the structure of the annual growth rings. Two Eucalyptus urophylla x Eucalyptus grandis hybrid clones were used in the study. Ten-year-old trees were selected and discs were removed from 13 longitudinal positions. The disks were prepared and the growth rings were subsequently identified and the samples used for maceration were collected. Twenty fibres were measured in the annual growth rings present in each longitudinal position. Results: In the longitudinal direction, within the annual growth rings, the fibre dimensions and their quality indices did not show a well-defined pattern of variation. In the radial direction, the length, cell wall thickness, wall fraction, and Runkel ratio of the fibres tended to increase following the pith-bark direction, while the lumen diameter and flexibility coefficient decreased. Conclusion: Nevertheless, the fibre width and fibre slenderness index did not present a well-defined pattern of variation in the radial direction.

The structure and formation of giant Marimo (Aegagropila linnaei) in Lake Akan, Japan

Aegagropila linnaei is a freshwater green alga, which at one time was distributed widely in the northern hemisphere. The aggregate often forms beautiful spherical shapes known as “lake balls” or “Marimo”. The population of Marimo has been rapidly decreasing worldwide, and today the large Marimo, with a diameter of more than 12 cm, exit only in Lake Akan in Japan. However, how Marimo grow and maintain their unique spherical shape in natural habitats remains unsolved. Here we show that Marimo are “polished” into spheres by the rotation induced by wind waves. Such a process enhances the water exchange between the interior and exterior of the Marimo, thereby recycling nutrients for growth. Our results provide an intriguing model of a physical environment interacting with biological processes in a self-sustaining ecosystem. We also demonstrate that Marimo have a spherical annual ring structure, and their growth rate is associated with ice cover. The balance between the ecology of Marimo and the water environment in Lake Akan is highly vulnerable and at risk of irreversible degradation. We must endeavor to rescue Marimo from the fate of a "canary in the coal mine" of global climate change.

Identification of Calendar Years with Late Spring Frosts on the Basis of Anatomical Structure of Annual Rings of the Common Oak on the Zilair Plateau (Southern Urals)

Identification of Calendar Years with Late Spring Frosts on the Basis of Anatomical Structure of Annual Rings of the Common Oak on the Zilair Plateau (Southern Urals)

Numerical modelling of wood under combined loading of compression perpendicular to the grain and rolling shear

Numerical modeling is an efficient tool for experimental validation and for gaining a deeper understanding of complex material phenomena, especially when causal relationships are overlaid by material variability. Wood is such a highly orthotropic and complex material, which in engineering problems however is considered as macro-homogeneous. The aim of this study is to numerically investigate stress and strain states of wood in the radial-tangential plane and the influence of the orthotropic material behavior on the structural response. Model validation is based on experiments performed on clear wood of Norway spruce (Picea abies) by using a biaxial test setup. Three material models were used, namely Hill’s plasticity model, the Hoffman criterion and a novel quadratic multi-surface (QMS) criterion. After validation on the local material scale, the models were applied to the engineering problem of compression perpendicular to the grain for studying the effect of the unloaded length. As a novel part, the influence of the annual ring structure on the local material behavior and the global elasto-plastic force–displacement behavior of wood under compression perpendicular to the grain were numerically investigated. Hill’s failure criterion was found to be the least suitable at both length scales, local material behavior and global structural response. The Hoffman and the QMS criteria showed quite good agreement with the biaxial experiments in terms of force–displacement relations and strain distributions for different loading situations, especially for combinations with radial compression, while there was less agreement with experiments for the behavior of combinations with tangential compression. Application of these material models to compression perpendicular to the grain for studying the unloaded length effect yielded similar trends as observed in structural tests. A reasonable and similar force–displacement response by Hoffman and QMS criteria was observed, while Hill’s model yielded significantly overestimated force carrying capacity. Differences in force–displacement response for different loading situations were well in line with literature findings and the influence of the annual ring curvature on the overall force–displacement behavior could be quantified.

What Quantitative Anatomy Can Provide for Kinetics of Xylogenesis: Analysis of Cell Radial Diameters

A theoretical and experimental verification of a simple hypothesis was carried out in this study to determine if features of the anatomical structure of coniferous annual rings (in a case study of pine trees from moisture-deficient growth conditions in the steppe zone) quantified in tracheidograms of annual rings can be used to reconstruct the kinetics of seasonal growth. During two sharply different growth seasons, sampling was performed periodically, and seasonal growth of tree rings was measured where the forming annual ring was separated into zones (cambium, extension zone, zone of cell wall thickening, zone of mature tracheids). Based on these data and total tracheidograms, a simple scheme for converting the variability of the radial cell sizes into cumulative and differential cell production curves was proposed. Statistical analysis revealed both correspondence and discrepancies between theoretical and experimental data, showed the prospects of the proposed approach, and suggested the need for longer seasonal observations

Wood annual ring structured elastomer composites with high thermal conduction enhancement efficiency

The construction of heat conduction pathways in a polymer matrix is crucial for improving the thermal management performance of polymer composites. Three-dimensional thermally conductive scaffolds with highly aligned filler structures are attractive to construct rapid conduction pathways in polymer composites. A typical example is the xylem tissue in tree trunks, although it is to transport water and nutrients upward. Herein, inspired by the annual ring structure of natural trees, a thermal conductive carbon nanotubes-based skeleton (T-SGM) with long-range ordered microstructures was developed through combining one-dimensional carbon nanotubes and two-dimensional graphene oxide sheets in alkaline conditions, assisted by a combined drying method. After the incorporation of T-SGM into polydimethylsiloxane resin, wood annual ring structured composites were prepared and they can exhibit a through-plane thermal conductivity enhancement of ~744% at a low skeleton content of 6.0 vol%. In addition, the excellent resilience of the composites is still maintained. The infrared thermal imaging results demonstrated that wood annual ring structured composites have high potential in thermal management applications.

Evaluation of rolling shear modulus and strength of Japanese cedar cross-laminated timber (CLT) laminae

Cross-laminated timber (CLT) panels are fabricated with their layers stacked crosswise. Owing to the low shear modulus and strength in the rolling shear direction, the shear properties of cross-layers influence the overall deflection and shear capacities of CLT panels. The aim of the present study is to determine the rolling shear properties of Japanese cedar and investigate how annual ring patterns and lamina geometry influence shear properties. Using a test configuration similar to the standard shear test configuration prescribed in European Standards (EN 408), a single lamina shear test was conducted. To investigate the influence of thickness-to-width aspect ratio of the lamina on the rolling shear properties, samples with three different widths, including 62, 88, and 112 mm, with a constant thickness of 24 mm were tested. The geometrical features of the annual ring patterns of each test sample were measured. The mean rolling shear moduli were 72, 91, and 109 MPa, and the mean rolling shear strengths were 1.54, 1.83, and 2.02 MPa for the 62-, 88-, and 112-mm sample widths, respectively. Shear strength was highly correlated with shear modulus. The mean shear modulus and strength, in addition to the 5% quantile, increased with an increase in lamina width. Across all sample widths, rolling shear modulus and strength decreased with an increasing radial distance from the pith. Using the principle of continuum mechanics, the influence of the annual ring angle relative to the shear force direction was examined quantitatively using the finite element method. The results suggest that shear modulus and its variance are influenced greatly by the annual ring structure.

Linkages between the Structure of Annual Rings of Scots Pine and Stand Density in the Region of the Chernobyl Accident

We have studied the features of annual ring development in stands of Bryansk oblast polluted by radionuclides from the Chernobyl accident. The evidence of relationships between average annual radial increment and the average width of spring and summer layers of timber within an annual ring and stand density is observed in 80-year-old blueberry pine forests. We find direct links between annual increment and its spring and summer components with average distance between trees. The stand density has the most pronounced effect on the spring growth of timber, with an increment gradient from 0.204 to 0.244 mm m–1. In summer it varies from 0.038 to 0.066 mm m–1. The contribution of the late timber in a tree ring increases from 50.4–54.8% in the least dense to 72.5–75.8% in the densest stands. However, chronic irradiation does not differ across the stand density gradient. The stimulation of the annual growth increment by irradiance is estimated from 50.4 to 51.9%. It contributes from 39.1 to 46.1% of the spring increment to 43.2–58.6% of the summer increment with 95% confidence.

Evidences of wider latewood in Pinus sylvestris from a forest-steppe of Southern Siberia

Climate affects wood formation with consequences for the functioning and survival of trees. Since tree-rings tissues (i.e., earlywood and latewood) are formed at different time in the season, the impact of climate change might differently affect their functions.In this study, we combine quantitative tracheid anatomy with the Vaganov-Shashkin growth model (VS-model) to investigate how summer drought affected the annual ring structure of Pinus sylvestris L. from a forest-steppe zone in Southern Siberia. In particular, we used climate-growth relationships over a 50-year period to identify the timing of climatic signal of early-, transition-, and late-wood tracheid’s diameters (DEW, DTW and DLW). Corresponding daily growth rates (Gr) obtained by the VS-model were applied to calculate the changes in the width of the relative tree-ring sectors considering different levels of aridity.Results indicate that tracheid size is sensitive to drought with temporal shifts among the climatic signal of DEW (in May), DTW (June) and DLW (July). A comparison of modeled daily-growth rate cumulated over the climatic window of each ring sector and grouped by years with different level of aridity, indicated that a release of summer drought mostly affected the widths of the transition (+28.1%) and (+48.6%) latewood sectors, thus matching observations performed on the same cores.These results suggest that current changes in climate seasonality, as occurring in the selected area, are positively impacting both the hydraulic efficiency (by increasing the diameter of the earlywood cells) and the latewood width of the wood produced in the area.

Структура годичных колец древесины сосны обыкновенной в зоне аварии на Чернобыльской АЭС в связи с густотой древостоев

RUSSIAN JOURNAL OF FOREST SCIENCE, 2018, No. 4, P. 285-291 LINKAGES BETWEEN STRUCTURE OF ANNUAL RINGS OF SCOTS PINE AND STAND DENSITY IN THE REGION OF CHERNOBYL ACCIDENT A. A. Belov All-Russian Research Institute of Silviculture and Mechanization of Forestry Institutskaya st. 15, Pushkino, Moscow Oblast, 141202, Russia E-mail: belov@roslesrad.ru Received 29 September 2016 We studied features of annual rings development in the stands of Bryansk Oblast polluted by radionuclides from Chernobyl accident. The evidence of relationships between zverage annual radial increment, average width of spring and summer layers of timber within an annual ring and stand density was observed in 80-years old blueberry pine forests. We found direct links between annual increment, and its spring and summer components, with average distance between trees. The stand density had the most pronounced effect on the spring growth of timber with the increment gradient from 0.204 to 0.244 mm m -1 . While in summer it varied from 0.038 to 0.066 mm m -1 . The contribution of the late timber in a tree-ring increased from 50.4-54.8% in the least dense to 72.5-75.8% in the densest stands. However chronic irradiation did not differ across the stand density gradient. Stimulation of the annual growth increment by irradiance was estimated from 50.4 to 51.9%. It contributed from 39.1 to 46.1 of the spring increment to 43.2-58.6% of the summer increment with 95% confidence. Keywords: Scots pine, stand density, radiocaesium soil pollution, radial increment, tree-ring structure. DOI: 10.1134/S0024114818040046 REFERENCES Antanaitis V.V., Zagreev V.V., Prirost lesa (Forest yield), Moscow: Lesnaya promyshlennost', 1981, 100 p. 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Bitvinskas T.T., Dendroklimaticheskie issledovaniya (Dendroclimatic studies), Leningrad: Gidrometeoizdat, 1974, 172 p. Demakov Y.P., Vozmozhnosti dendrokhronologii v indikatsii i prognoze techeniya prirodnykh i antropogenno obuslovlennykh protsessov (Advances of dendrochronology in indication and prediction of natural and human induced processes), Mathematical and physical methods in ecology and monitoring of environment , Proc. Conf. Moscow, 23-25 October 2001, Moscow: Izd-vo MGUL, 2001, pp. 257-263. Ishutkin V.V., Gosudarstvennyi doklad ''O sostoyanii okruzhayushchei prirodnoi sredy Bryanskoi oblasti'' (The State report on the status of environment in Bryansk oblast in 2009), Bryansk: Komitet prirodopol'zovaniya i okhrany okruzhayushchei sredy, litsenzirovaniya otdel'nykh vidov deyatel'nosti Bryanskoi oblasti, 2010, 294 p. Lomov V.D., Stroenie godichnykh sloev drevesiny sosny v svyazi s razmeshcheniem derev'ev i sostavom drevostoya (Structure of annual rings of pine timber at various tree locations and specie composition of forest), In: Voprosy lesovedeniya i lesovodstva (Challenges in forest science and silviculture) : Izd-vo MLTI, 1985, Vol. 176, pp. 50-53 (101 p.). Matveev S.M., Rumyantsev D.E., Dendrokhronologiya (Dendrochronology), Voronezh: Izd-vo VGLTA, 2013, 139 p. Moiseev B.N., Strakhov V.V., Raschety vozmozhnoi reaktsii lesov Rossii na global'noe poteplenie klimata (Evaluation of possible feedback of Russian forests to global climate warming), Lesnoe khozyaistvo , 2002, No. 4, pp. 5-8. Ovodov A.V., Kachestvo drevesiny sosny v nasazhdeniyakh, sozdannykh posevom i posadkoi: Avtoref. diss. kand. s.-kh. nauk (Timber quality of pine plantations grown from saplings and from seeds. Extended abstract of candidate's agric. sci. thesis), Arkhangelsk: SAFU, 2010, 16 p. Prikaz Rosleskhoza N 192 , 1994, September 5. Rudakov V.E., Metod izucheniya vliyaniya kolebanii klimata na tolshchinu godichnykh kolets (A method of study of climate fluctuations effect on thickness of tree rings), Doklady Akademii nauk Armyanskoi SSR , 1951, Vol. 13, No. 3, pp. 75-79. Sanitarnye pravila v lesakh Rossiiskoi Federatsii ( Sanitary regulations in forests of the Russian Federation ), 1992. Slyadnev A.P., Vliyanie biologicheskikh osobennostei sosnovykh nasazhdenii i azotnogo udobreniya na formirovanie godichnykh kolets (The effect of biological features of pine forests and the nitrogen fertilizer on annual ring development), Izvestiya vysshikh uchebnykh zavedenii. Lesnoi zhurnal , 1972, No. 6, pp. 69-74. Tyukavina O.N., Izmenenie assimilyatsionnogo apparata, vodnogo rezhima i struktury godichnogo kol'tsa sosny pod vliyaniem osusheniya. Avtoref. diss. kand. s.-kh. nauk (Alterations of assimilation apparatus, water regime and annual ring structure of pines under drainage. Extended abstract of candidate's agric. sci. thesis), Arkhangelsk: AGTU, 2003, 19 p. Vaganov E.A., Terskov I.A., Analiz rosta dereva po strukture godichnykh kolets (Growth of a tree: analysis of annual rings structure), Novosibirsk: Nauka, 1977, 94 p.

Comparison of the Structure of Juvenile and Mature Wood of Larix decidua Mill. from Fast-Growing Plantations in Poland

The main objective of this study was to reveal variations in the wood structure and to define the location of the boundary between juvenile and mature wood Larix decidua Mill. from fast growing tree plantations. To reach these findings, the samples of wood from four short-rotation plantations in Central Europe (Poland) were selected and compared. The procedure used to determine the demarcation point between juvenile and mature wood resulted in strong correlations between the width of growth rings and the initial cambial age. It was found that the structure of wood from fast-growing trees differs from commercially available timber. The wood derived from plantations revealed wider annual rings than wood from natural forests. The analysis of the variability of wood structure resulted in defining the location of the boundary between juvenile and mature wood. Based on the analysis of structure of annual rings, the boundary of juvenile wood in fast-growing larch is placed between the 12th and 15th annual ring. The investigated material contained high proportions of juvenile wood, which makes up more than 70% of trunk volume. On the microscopic level, no visible changes, indicating the presence of a mature wood zone, were found.

Stress reactions of Scots pine trees to injuring by ground fire

Controlled burning has been carried out to stimulate moderate ground fire in the Scots pine (Pinus sуlvestris L.) stand (age class I) in the Krasnoyarsk forest steppe at the beginning of the growing season. The structure of annual rings and trophic supply, as well as the cambial zone antioxidant system condition and the content of photosynthetic pigments in the needles of dominant and suppressed trees in the experimental and control plots, were studied 3 h, 5 days, and 2.5 months after the fire. The fire narrowed the annual ring width, since the number and size of early and late tracheids decreased. The primary reaction to pyrogenic heat shock (sharp reduction of chlorophyll content in needles and manifestation of oxidative stress in the stem cambial zone) was an elevated level of hydrogen peroxide and activity of most antioxidant enzymes and a reduction in the nonstructural carbohydrates pool. Restoration of the cambium function after the fire was promoted by an increased activity of amylase, invertase, and peroxidase.

Dynamic response of earlywood and latewood within annual growth ring structure of Scots pine subjected to changing relative humidity

Abstract Scots pine (Pinus sylvestris L.) was subjected to relative humidity (RH) changes, and the dynamic strain field on the surface and in the bulk wood was monitored by digital speckle pattern interferometry and X-ray computed microtomography assisted by digital volume correlation. If a freely shrinking specimen was subjected to an RH decrement, earlywood (EW) and latewood (LW) at the surface layer were deformed in the opposite directions at the beginning of drying due to moisture gradient across the specimen. As a result, the surface and core behaved as independent sub-components, with the surface restrained in its response by the dimensionally unchanged core. With time, both LW and EW shrank as moisture content (MC) became uniform across the specimen. When an entire wood specimen was restrained from movement and desiccated in ambient RH, EW was stretched to compensate for the considerable shrinkage of LW. Knowledge about surface deformation at the annual ring level as a function of varying RH may be helpful to assess the risks associated with the damage of paint layers caused by fluctuations of ambient RH.

Determination of Trace Elements Across Annual Ring Structure of Ferromanganese Nodule by Laser Ablation-ICP-MS

Trace elements were determined across the annual ring structures of a ferromanganese nodule by laser ablation/inductively coupled plasma mass spectrometry (LA-ICP-MS). The determined values were obtained from 30 points by spatial-resolution analysis using LA-ICP-MS. The ferromanganese nodule was also sampled by hand-picking, and the samples were determined by ICP-MS in order to compare the determined values by LA-ICP-MS. With internal standard corrections using Mg or Mo, the determined values by LA-ICP-MS were in good agreement with those by ICP-MS. LA-ICP-MS verified that the Fe concentration increased with increasing Co and REE concentration in a ferromanganese nodule. This fact seemed to indicate that the determined values by LA-ICP-MS were acceptable. Furthermore, the variation of a cerium anomaly across the annual ring structure was verified by LA-ICP-MS. A positive cerium anomaly was observed at the points where Fe was enriched. From these results, the determination method for a spatial-resolution analysis of a ferromanganese nodule using LA-ICP-MS was developed and achieved.