• Journal of Forest and Environmental Science
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• v.34 no.6
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• pp.429-434
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• 2018

Extractable iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) contents and their distribution with depths in soils of forested and adjacent deforested areas at Jahazpura, Teknaf, Cox's Bazar of Bangladesh were studied. The soils under forest showed higher levels of DTPA-extractable micronutrients in all three layers of soil in comparison to those of the deforested areas. The differences between forested and deforested sites were, in most cases, significant.. The top soils of forested sites had the higher contents of micronutrient and generally decreased with depth in forested soils, while there was no regular trend of distribution in deforested soils. The study also revealed that contents of extractable Fe, Mn and Cu were sufficient in all depths and sites but Zn was deficient in bottom layer of forested and all three layers of deforested sites. The results suggested that organic matter, clay and soil pH could play important roles in concentrations and distributions of micronutrients in soils of the study areas.

• Journal of Plant Biology
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• v.7 no.2
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• pp.1-8
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• 1964

Cha, Jong Whan (Dept. of Biology, Graduate School, Dong Kuk Univ.) The changes of chemical properties of forest soils in dry and wet seasons. Kor. Jour. Bot. VII(2): 1-8, 1964. Soil selected for the present investigation was collected from a mountain of the Forestry Experiment Station of the vicinity of Seoul. The forest communities studied were three forest and a unplanted soils. The soil samples were obtained from each forest type during dry and wet seasons. And these samples were collected from four horizons of all communities respectively. It was showed that exchangeable hydrogen was increased by rainfall, and total exchangeable base decreased in the same way. The content of nitrogen is washed away by rainfall, especially ammonium nitrogen was highly significant between dry and wet season. On the contrary, organic matter and available phosphorus were of no significant difference between dry and wet seasons. The values of pH appeared a different response in dry and wet seasons according to the plant communities. The needle-leaved forest soils showed more acidity than the broad-leaved forest soils, and the least acidity in open places. All nutrients in soil studied gradually decreased down the profiles. According to statistical analyses of the soil components among all soil horizons, total exchangeable bases in wet season indicated only significant at 1%. Exchangeable hydrogen and organic matter of the soil in dry season was particularly very low with increased depth in the profile. The fertility level of most forested soils selected for the present investigation is low according to chemical tests for available nutrient elements.

• Advances in environmental research
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• v.4 no.4
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• pp.247-262
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• 2015

The few lignin biomarker studies conducted in tropical environments are hampered by having to use references signatures established for plants and soils characteristic of the temperate zone. This study presents a lignin biomarker analysis (vanillyls (V), p-hydroxyls (P), syringyls (S), cinnamyls (C)) of the dominant plant species and soil horizons as well as an analysis of the interrelated terrigenous organic matter (TOM) dynamics between vegetation and soil of the $Tapaj{\acute{o}}s$ river region, an active colonization front in the Brazilian Amazon. We collected and analyzed samples from 17 fresh dominant plant species and 48 soil cores at three depths (0-5 cm, 20-25 cm, 50-55 cm) from primary rainforest, fallow forest, subsistence agriculture fields and pastures. Lignin signatures in tropical plants clearly distinguish from temperate ones with high ratios of Acid/aldehyde of vanillyls ((Ad/Al)v) and P/V+S. Contrary to temperate environments, similarly high ratios in tropical soils are not related to TOM degradation along with pedogenesis but to direct influence of plants growing on them. Lignin signatures of both plants and soils of primary rainforest and fallow forest clearly distinguish from those of non-forested areas, i.e., agriculture fields and pastures. Attalea speciosa Palm trees, an invasive species in all perturbed landscapes of the Amazon, exhibit lignin signatures clearly distinct from other dominant plant species. The study of lignin signatures in tropical areas thus represents a powerful tool to evaluate the impact of primary rainforest clearing on TOM dynamics in tropical areas.

• The Korean Journal of Ecology
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• v.28 no.6
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• pp.417-431
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• 2005

Soils of Korea experienced with long-term acidic deposition have been exhaustively leached exchangeable base cation (BC) for plant nutrient comparable with soils of forest decline areas in Europe and N. America. Ratios of $BC/Al^{3+}$ of most soils are below than 1, which value is critical load for plant growth. Acid soil applied with dolomitic liming is increased as much as 20% and 244% in concentrations of $Ca^{2+}$ and $Mg^{2+}$, respectively, as well as shrub leaves increase much cation uptake by 1 year later. Ions of $NO_3^-$ and $NH_4^+$ in acid rain are absorbed by the canopy acted as the sink but f is leached out from the canopy to throughfall as the source at Gwangneung forest with a little of acidic deposition, however, such sink and source functions are not found at Kwanaksan forest because of so much deposition. In coniferous and deciduous forested watershed ecosystems ions of $K^+$, $Cl^-$, $NO_3^-$ and $SO_4^{2-}$ from throughfall are retained in forest floor but ions of $Na^+, $Mg^{2+}$ and $Ca^{2+}$ are leached from the floor to streamwater.

• Journal of Forest and Environmental Science
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• v.29 no.2
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• pp.116-124
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• 2013

Differences in rates and patterns of nitrogen cycling have been correlated with nitrogen stable isotope measurements in forest ecosystems of tropical and temperate regions, but limited similar work has been conducted in sub-tropical forests. This study investigated patterns in stable N isotopic composition in a subtropical forest in Taiwan by sampling three soil profiles and overstory and understory foliage. Soil ${\delta}^{15}N$ in the forest floor ranged from -1.8 to -1.8‰. Mineral soils had higher ${\delta}^{15}N$ (4.1 to 6.0‰). Foliage ${\delta}^{15}N$ in overstory trees ranged from -6.6 to -2.0‰, and understory foliage ${\delta}^{15}N$ ranged from -5.0 to -1.2‰. There was a weak correlation between foliar % N and ${\delta}^{15}N$ ($r^2=0.214$). Compared to results from similar surveys in tropical and temperate forests, foliar ${\delta}^{15}N$ values were generally lower. These results help highlight the need for improved knowledge regarding the relationships between patterns in N stable isotopes and processes affecting rates of N cycling, especially as related to wider scale patterns in forest ecosystems within the east-Asia region.

• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.127-137
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• 1987

This study was conducted to examine the effects of trampling on the changes in soil and vegetation around the trails. The study areas were established both on the trails and in the forested areas located in Ui and Jeongnung valleys at Pukhansan National Park. Soil core sampling, measurements of vegetations and counts of persons visited per hour were done during the period from April 6 to October 9, 1986. The physical properties of soils became better with increasing distances from the trail, and the best conditions were observed in the forested areas. The differences were not significant among the zones within the trailside. More number of individuals and basal area (or coverage) in woody plants were observed in the forested areas than at trailsides. For the herb layer, however, more number of individuals and coverage were shown at the trailside. In the Ui valley, the quantitative measures of herbaceous plants decreased as the bulk density and penetration resistance increased. In the Jeongnung valley, however, only bulk density was negatively related to the quantitative measures. The fact that there were poor relations between soil factors and quantitative measures of herbaceous plants in Jeongnung valley might be influenced by other factors rather than soil compaction. Thus, more research would be needed to understand the critical factors affecting the vegetational changes in recreation areas.