Forest Soils In Japan Research Articles

Impact of Heat on Soil Water Repellency in Forest Soils from Different Depths using Water-Repellent Japanese Cedar (Cryptomeria japonica) Forest Soil

ome soils under plant species, such as casuarina, pine, eucalyptus, cedar, and cypress, show water- repellent conditions. Wildfires are common in forests dominated by these plant species as they produce highly flammable debris. The heat generated during wildfires alters soil characteristics, including soil water repellency (SWR). The responses of SWR to heat can differ depending on the heating temperature and the soil depth. This study aimed to examine the effects of different heating temperatures on SWR through a soil profile using Japanese cedar (Cryptomeria japonica) forest soil in Japan. Soil samples were collected from four different depths (0-5, 5-10, 10-15, 15-20 cm). Soils were exposed to heat with seven heating temperatures (TH) (50, 100, 150, 200, 250, 300, and 350° C) separately for 1 h using a programmable muffle furnace. The degree (contact angle) and the persistence of SWR in both heated and non-heated samples were measured using the molarity of an ethanol droplet test and the water drop penetration time (WDPT) test, respectively. In non-heated soils, the 0-5 cm layer showed the highest SWR (contact angle ~110°; WDPT≥3600 s). SWR decreased with depth to be non-repellent at 15-20 cm (contact angle≤90°; WDPT≤1 s). In heated samples, SWR of 0-5, 5-10, and 10-15 cm layers decreased with increasing TH, while the selection from 15-20 cm was non-repellent in all treatments. Soils of 0-5 cm depth showed extreme SWR (WDPT=≥3600 s) up to 200° C and became non-repellant at 250° C, while those of 5-10 cm showed extreme SWR up to 150° C, severe SWR (WDPT~1350 s) at 200° C, and became non- repellent at 250° C. The soils from 10-15 cm showed severe SWR (WDPT~2100 s) at TH of 50° C and became non-repellent at 100° C. Results revealed that upper soil layers with higher SWR required higher TH to become non-repellent, and soils from lower layers with lower SWR became non-repellent at lower TH. Further experiments are necessary to identify the changes in molecular levels of organic matter in response to the impacts of heat on SWR. 
 Keywords: Cryptomeria japonica, Laboratory heating, Soil water repellency, Wildfires

Classification of volcanic soils in the Soil Classification System of Japan and verification based on forest soils

ABSTRACT In 2017, the Japanese Society of Pedology (the Fifth Committee for Soil Classification and Nomenclature) established the Japanese soil classification system. In the classification system, all the soils derived from volcanic ejecta (volcanic ash, pumice, scoria, etc.) are classified into the Great Group of Andosols, excluding Man-made and Organic soils, although some volcanic soils were classified into other soil groups, such as the Podozols and Brown forest soils in the previous classification systems. The aim of the present study was to verify and propose revision for the new system based on physicochemical data collected from forest soils across the Japan archipelago. Approximately 20% of the forest soils have andic properties and were classified into the Andosols in the Soil Classification System of Japan, which is consistent with the Andisols in Soil taxonomy and Andosols in World Reference Base for Soil Resources, excluding a few soils with low andic horizon thickness. Many other forest soils that were not classified into Andosols possessed some of the regosolic andic properties, and it was challenging to classify them into Regosolic Andosols or Brown forest soils. Therefore, additional diagnostic activities on the volcanic ejecta and glass are required to classify such soils appropriately. In the new classification system, the Fulvic Andosols soil group was abolished and substituted with the Humic and Brown-humic subgroups under the Non-allophanic and Allophanic Andosols, respectively. The revision was consistent with the traditional forest soil classification system. In conclusion, the classification of volcanic soils in the Soil Classification System of Japan was verified using forest soil data in Japan. Abbreviations CFSJ: Classification of Forest Soils in Japan (1975); CSCSJ: Comprehensive Soil Classification System of Japan, 1st approximation (2011); SCSJ: Soil Classification System of Japan (2017); ST: Keys to Soil taxonomy, Twelfth Edition (2014); USCSJ: Unified Soil Classification System of Japan, 2nd Approximation (2002); WRB: World Reference Base for Soil Resources (2014, 2015 updated)

Priming effect of Miscanthus sinensis derived biochar on brown forest soil

ABSTRACT The role of biochar in the mitigation of CO2 emissions has been extensively studied in agricultural soils but is not well understood in Japanese forest soils, especially in relation to CO2 emissions from applied biochar and native soil C (i.e., the priming effect; PE). We hypothesized that the type of biochar and/or the application method (mixed or sprinkled) affect the direction and magnitude of PE in forest soil, and in particular, negative PE can be achieved relatively easily if biochar produced under higher temperature conditions were sprinkled on the soil surface. To test our hypothesis, we measured CO2 emissions from biochar-amended brown forest soil in Japan and examined its PE by conducting a medium-term (~4 months) incubation study. As substrates, we used plain straw from the C4 grass Miscanthus sinensis (SU) and two qualities of biochar produced from it at either 300°C (BC300) or 800°C (BC800) and compared two application methods: mixed into or sprinkled onto the soil. BC800 had a greater C content and C:N ratio as well a lower volatile matter content and higher nonvolatile matter content than BC300. SU had the lowest C content and C:N ratio of all the substrates. We found that biochar quality (volatile and nonvolatile matter content) was clearly related to the decomposition rate when mixed into the soil, but we could not find this relationship when biochar was sprinkled onto the soil. The addition of biochar to the soil induced a positive PE in the early stages (except for BC800 sprinkled) but suppressed CO2 emissions from native soil organic matter (negative PE) in the later stages, whereas the PE with SU application was always positive regardless of application method. Our results suggest that when biochar is sprinkled onto soil it is more likely to suppress soil-derived CO2 emission than when mixed in soil; however, the trend based on biochar quality was unclear.

Abundance of the soil entomopathogenic fungus Metarhizium anisopliae sensu lato in agricultural field and forest soils in Japan

Abundance of the soil entomopathogenic fungus Metarhizium anisopliae sensu lato in agricultural field and forest soils in Japan

Draft Genome Sequence of a Caffeine-Utilizing Bacterium, Cupriavidus sp. Strain D384.

ABSTRACTCupriavidus sp. D384 was isolated from forest soil in Japan and is known to utilize caffeine as a sole source of carbon and energy. We report here the 6,835,230-bp genome sequence for this strain, which contains 6,116 predicted coding sequences, including gene operon for alkaloid degradation.

Cladophialophora inabaensis sp. nov., a New Species among the Dark Septate Endophytes from a Secondary Forest in Tottori, Japan.

A novel species of Cladophialophora is herein described from the natural environment of secondary forest soil in Japan, which was able to be colonized by the host plant root. Morphological observations indicated that the isolate is distinct from previously identified species, and, thus, is described as the new species, C. inabaensis sp. nov.

Differences in the Spatial Variability Among CO2, CH 4, and N 2O Gas Fluxes from an Urban Forest Soil in Japan.

The spatial variability of carbon dioxide (CO(2)), methane (CH(4)), and nitrous oxide (N(2)O) fluxes from forest soil with high nitrogen (N) deposition was investigated at a rolling hill region in Japan. Gas fluxes were measured on July 25th and December 5th, 2008 at 100 points within a 100 × 100 m grid. Slope direction and position influenced soil characteristics and site-specific emissions were found. The CO(2) flux showed no topological difference in July, but was significantly lower in December for north-slope with coniferous trees. Spatial dependency of CH(4) fluxes was stronger than that of CO(2) or N(2)O and showed a significantly higher uptake in hill top, and emissions in the valley indicating strong influence of water status. N(2)O fluxes showed no spatial dependency and exhibited high hot spots at different topology in July and December. The high N deposition led to high N(2)O fluxes and emphasized the spatial variability.

Isolation of Bacillus sp. strains capable of decomposing alkali lignin and their application in combination with lactic acid bacteria for enhancing cellulase performance

Effective biological pretreatment method for enhancing cellulase performance was investigated. Two alkali lignin-degrading bacteria were isolated from forest soils in Japan and named CS-1 and CS-2. 16S rDNA sequence analysis indicated that CS-1 and CS-2 were Bacillus sp. Strains CS-1 and CS-2 displayed alkali lignin degradation capability. With initial concentrations of 0.05-2.0 g L(-1), at least 61% alkali lignin could be degraded within 48 h. High laccase activities were observed in crude enzyme extracts from the isolated strains. This result indicated that alkali lignin degradation was correlated with laccase activities. Judging from the net yields of sugars after enzymatic hydrolysis, the most effective pretreatment method for enhancing cellulase performance was a two-step processing procedure (pretreatment using Bacillus sp. CS-1 followed by lactic acid bacteria) at 68.6%. These results suggest that the two-step pretreatment procedure is effective at accelerating cellulase performance.

A pedotransfer function for estimating bulk density of forest soil in Japan affected by volcanic ash

Pedotransfer functions (PTFs) for estimating bulk density (BD) of forest soils in Japan affected by volcanic ash were developed using 3513 stone-free soil data. We found that 29 existing PTFs of five empirical types and one physical type generally overestimated the BD. This occurred because volcanic soil with the unique physical and chemical properties and forest soils with high pore volume resulted in lower BD and higher organic carbon content (OC) compared with other soil groups and produced a much lower bulk density of the ‘pure’ mineral fraction, a parameter of the physical PTF (1.153 in this study), compared with previous studies. Revised PTFs were newly developed by a non-linear least-squares method using the same algorithms of the six types of published PTFs. The best fit revised PTFs were a decimal one, BD=1/(0.882+0.133OC), and a physical one based on organic matter fraction (OM), BD=100/[(OM/0.140)+{(100−OM)/1.152}]. The revised PTFs predicted 37% of the samples to within ±10% and 67% of the samples to within ±20% in relative error for BD and explained 68% of BD variations. The variable mixture proportion of volcanic ash in the soils, the differences of soil textures, and the topographic conditions of the forest soils in Japan may have caused the variation in the observed BD.

Volcanic ash additions control soil carbon accumulation in brown forest soils in Japan(SSPN Award Paper)

Volcanic ash additions control soil carbon accumulation in brown forest soils in Japan(SSPN Award Paper)

Volcanic ash additions control soil carbon accumulation in brown forest soils in Japan

The objective of the present study was to clarify the influence of volcanic ash addition on soil carbon stocks and the carbon accumulation process in brown forest soils (BFS) in Japan. The degree of volcanic ash addition to the soil was estimated according to the acid ammonium oxalate extractable aluminum (Alox) and lithic fragment contents, and their vertical distribution patterns. The BFS was classified in order of increasing volcanic ash influence on the soil into the following types: high Alox content with no gravel (H-Alox-NGv), high Alox with a high gravel content (H-Alox-Gv), moderate Alox (M-Alox), and low Alox (L-Alox), and then analyzed for carbon content, carbon amount, carbon stock, Alox amount and pyrophosphate extractable aluminum (Alpy) amount. The correlation between the carbon and Alpy amounts and the relationship between the Alpy and Alox amounts in the BFS samples indicated that the amount of carbon is determined by Al—humus complex formation, which is defined by the active Al generated from additional volcanic ash in BFS soil samples of BFS. Therefore, soils with thicker horizons and greater amounts of Alox had higher carbon levels in deeper horizons. For this reason, soil carbon stocks at depths of 0–30 cm and 0–100 cm, and in the effective soil depth of BFS, were larger and followed the order H-Alox-NGv = H-Alox-Gv > M-Alox > L-Alox. Furthermore, successive accumulations of volcanic ash on the soil surface promoted soil carbon accumulation as a result of the development of the surface horizon in H-Alox-NGv BFS. Our results suggest that volcanic ash additions control the soil carbon accumulation of forest soil in Japan.

Proposal for advanced classification of brown forest soils in Japan with reference to the degree of volcanic ash additions

The advanced classification of brown forest soils (BFS) is based on the specific properties of these soils, including the acid ammonium oxalate extractable aluminum (Alox) and lithic fragment contents, as well as their vertical distributions in the soil profile. In the present study, these properties were used to classify BFS, resulting in four types: (1) H-Alox-NGv BFS, (2) H-Alox-Gv BFS, (3) M-Alox BFS, (4) L-Alox BFS. H-Alox-NGv BFS is derived from volcanic ash characterized by a high Alox content and no lithic fragment, whereas L-Alox BFS is derived from weathered bedrock and has a low Alox content. H-Alox-Gv BFS and M-Alox BFS are derived from mixtures of volcanic ash and weathered bedrock. H-Alox-Gv BFS is characterized by high Alox content and many lithic fragments, whereas M-Alox BFS has moderate Alox content. H-Alox-NGv BFS and black soils (BLS) develop from accumulated volcanic ash, as indicated by declining Alox and clay content with decreasing depth in the surface horizons, as a result of successive additions of less-weathered volcanic ash to the soil surface.

Methylovulum miyakonense gen. nov., sp. nov., a type I methanotroph isolated from forest soil

A novel methanotroph, designated strain HT12(T), was isolated from forest soil in Japan. Cells of strain HT12(T) were Gram-reaction-negative, aerobic, non-motile, coccoid and formed pale-brown colonies. The strain grew only with methane and methanol as sole carbon and energy sources. Cells grew at 5-34 °C (optimum 24-32 °C). The strain possessed both particulate and soluble methane monooxygenases and assimilated formaldehyde using the ribulose monophosphate pathway. The major cellular fatty acids were C(16 : 0) (46.9 %) and C(14 : 0) (34.2 %), whereas unsaturated C(16) fatty acids, typical of type I methanotrophs, were absent. Comparative 16S rRNA gene sequence analysis showed that the most closely related strains were Methylosoma difficile LC 2(T) (93.1 % sequence similarity) and Methylobacter tundripaludum SV96(T) (92.6 % similarity). Phylogenetic analysis based on the pmoA gene indicated that strain HT12(T) formed a distinct lineage within the type I methanotrophs and analysis of the deduced pmoA amino acid sequence of strain HT12(T) showed that it had a 7 % divergence from that of its most closely related species. The DNA G+C content was 49.3 mol%. Based on this evidence, strain HT12(T) represents a novel species and genus of the family Methylococcaceae, for which the name Methylovulum miyakonense gen. nov., sp. nov. is proposed. The type strain of the type species is HT12(T) ( = NBRC 106162(T) = DSM 23269(T) = ATCC BAA-2070(T)).

Two new species of Pythium, P. senticosum and P. takayamanum, isolated from cool-temperate forest soil in Japan

Pythium senticosum and P. takayamanum spp. nov. were isolated from cool-temperate forest soil in Japan. P. senticosum can grow at 5 C and is fast growing at 25 C with a radial growth of 22.2 mm 24 h−1. The species is morphologically characterized by ovoid to ellipsoid sporangia with apical papilla, ornamented oogonia with acute conical spines, and antheridia with broad attachment to oogonia. P. takayamanum is very different and can grow at 35 C. This species is morphologically characterized by its wavy antheridial stalks and ellipsoidal oogonia with constricted areas. Phylogenetic analyses of the ITS rDNA region and the partial COX2 gene showed that the two species are genetically distinct from each other and from their closest relatives. P. senticosum is closely related to P. dimorphum and P. undulatum whereas P. takayamanum is closely related to P. rhizosaccharum and P. parvum.

Chemical properties and pedogenesis of yellowish/yellow brown forest soils in the submontane and mountain zones of Kyushu district, southwestern Japan

This study aimed to clarify pedogenetic processes and classification of yellowish Brown Forest Soils according to the Classification of Forest Soils in Japan and the Yellow Brown Forest soils according to the Unified Soil Classification System of Japan in the warm and cool temperate forest of Kyushu district, Japan. In addition, the study aimed to clarify a problem with the Unified Soil Classification System of Japan. Thirty-six soil profiles of Brown Forest Soils, including 13 yellowish Brown Forest Soils and 15 Yellow Brown Forest soils, were compared with regard to their chemical properties and the relationship with climatic conditions was assessed. The yellowish Brown Forest Soils had thin A horizons, low pH and low levels of free oxides in the B horizons, and a low amount of silica and a high aluminum and iron to silica ratio. These features were related to the paleo reddish weathering. The immaturely developed A horizon of the yellowish Brown Forest Soils was caused by these weathered, low-activity substances. The Yellow Brown Forest soils had low levels of active iron oxides and a low activity ratio of free iron oxides compared with the Haplic Brown Forest soils in the same thermal climatic conditions. The activity ratio of free iron oxides was correlated to mean annual air temperature with the carbon stocks and with many other chemical properties. Accordingly, classification of Brown Forest Soils was clearer according to thermal climatic conditions. The activity ratio of free iron oxides can become an effective index that distinguishes Yellow Brown Forest soils under warm temperate lucidophyllous forest and Haplic Brown Forest soils under cool temperate broad-leaved deciduous forest with considerable vertical soil zonality.

Alkalibacillus silvisoli sp. nov., an alkaliphilic moderate halophile isolated from non-saline forest soil in Japan

Two alkaliphilic, moderately halophilic bacteria, designated BM2(T) and HN2, were isolated from non-saline forest soil in Japan. The cells of strain BM2(T) were motile, aerobic, rod-shaped and Gram-positive. The peptidoglycan was of the A1gamma type, and the diamino acid was meso-diaminopimelic acid. Growth was observed at NaCl concentrations between 5.0 and 25.0 % (w/v) (the optimum being 10.0-15.0 %, w/v), at pH 7.0-10.0 (optimum, pH 9.0-9.5) and at 20-50 degrees C. The predominant isoprenoid quinone was MK-7. The major cellular fatty acids were iso-C(15 : 0) and anteiso-C(17 : 0). The G+C content of total DNA of strain BM2(T) was 37.0 mol%. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain BM2(T) was most closely related to Alkalibacillus haloalkaliphilus DSM 5271(T) (98.0 % sequence similarity). DNA-DNA hybridization results indicated low levels of relatedness between strain BM2(T) and A. haloalkaliphilus JCM 12303(T) (23 and 16 % reciprocally), Alkalibacillus filiformis JCM 13893(T) (25 and 21 %) and Alkalibacillus salilacus JCM 13894(T) (27 and 19 %). On the basis of the phylogenetic and phenotypic characteristics, strain BM2(T) represents a novel species, for which the name Alkalibacillus silvisoli sp. nov. is proposed. The type strain is BM2(T) (=JCM 14193(T)=DSM 18495(T)).

日本の森林土壌におけるN2Oフラックス：土壌・植生の違いに着目して

日本の森林土壌におけるN2Oフラックス：土壌・植生の違いに着目して

Estimate equation of gas diffusion coefficient of forest soils in Japan

Estimate equation of gas diffusion coefficient of forest soils in Japan

General Chemical Properties of Brown Forest Soils Developed from Different Parent Materials in the Submontane Zone of the Kanto and Chubu Districts, Japan

It is essential to analyze chemical properties including the amount of various materials and the soil colloid characteristics in forest soils to forecast wood production and the distribution of and variations in the environmental functions of forest soils, such as conservation of stream water and carbon sequestration. Approximately 70% of the forest soils in Japan consists of Brown Forest Soils (BFS), which are considered to be typical zonal soils under the humid-temperate and warm-temperate regime of Japan. BFS were subclassifled into several groups according to the soil moisture environment along the slope and morphological properties. However, even the same type of soil may display different properties depending on the climatic conditions, parent materials and vegetation types. In the present study, the variations in the carbon content, nitrogen content, cation exchange capacity and some properties depending on the parent materials, were clarified by using 34 sola of BFS, and 3 sola of black soils (BLS) for comparison, which were distributed in the submontane zone of the Kanto and Chubu districts in central Japan under the same climatic conditions. We observed differences in the pH, cation exchange capacity, base saturation and clay content among BFS samples derived from various parent materials. The BFS derived from volcanic ash contained obviously larger amounts of carbon and nitrogen than the BFS derived from other parent materials. However, the BFS derived from volcanic ash differed from the BLS derived from volcanic ash in the vertical distribution pattern of carbon and nitrogen. Thus, even in the submontane zone of the Kanto and Chubu districts, the chemical properties of BFS varied considerably with the parent materials. It was concluded that the classification of BFS by the parent materials was useful for evaluating the ability of the BFS, that cover 70% of the forests in Japan, to store various materials.

Contribution of Parker and Product indexes to evaluate weathering condition of Yellow Brown Forest soils in Japan

Soil weathering is recognizable through study on physico-chemical characteristics of soil. In this study, Parker, ([(Na) a / 0.35] + [(Mg) a / 0.9] + [(K) a / 0.25] + [(Ca) a / 0.7]) × 100, and Product, [SiO 2 / (TiO 2 + Fe 2O 3 + SiO 2 + Al 2O 3)] × 100, weathering indexes, originally developed for study on rocks, were tested on Yellow Brown Forest soils from two different regions in Japan. The results showed that the contribution of the mentioned indexes can be used for study on soils weathering. In other word, in a two-dimensional coordination system where the axes are Parker and Product indexes, regarding to the chemical bases of the indexes, initial and lateral products of weathering can be tracked at the same time. Additionally, the indexes relations with soil color were studied after exposing the samples at a high temperature. Remarkable relationships between a* / b* ratio–parameters of psychometric chromaticness of color in CIE color standard system–and these two weathering indexes demonstrated that a* / b* ratio can be applied reliably to estimate the quantities of Parker and Product indexes in Yellow Brown Forest soils.