Search

Summary 1. Individual performance is a function of an individual’s traits and its environment. This function, known as an environmental filter, varies in space and affects community composition. However, filters are poorly characterized because dispersal patterns can obscure environmental effects, and few studies utilize longitudinal data linking individual performance to environment. 2. We model the effects of environmental filters on demographic rates of nearly all tree species (99) in a 25-ha subtropical rain forest plot. We develop a hierarchical Bayesian model of environmental filtering, drawing inspiration from classic studies of intraspecific natural selection. We characterize the specific environmental gradients and trait axes most important in filtering of demographic rates across species. 3. We found that stronger filtering along a given trait axis corresponded to less spatial variation in the value of favoured traits. 4. Environmental gradients associated with filtering were different for growth versus survivorship. 5. Species maximum height was under the strongest filtering for growth, with shorter species favoured on convex ridges. Shorter stature species may be favoured on ridges because trees on ridges experience higher wind damage and lower soil moisture. 6. Wood density filtering had the strongest effects on survival. Steep slopes and high available P in the soil favoured species with low-density wood. Such sites may be favourable for fast-growing species that exploit resource-rich environments. 7. Synthesis: We characterized trait-mediated environmental filters that may underlie spatial niche differentiation and life-history trade-offs, which can promote species coexistence. Filtering along trait axes with the strongest effects on local community composition, that is, traits with the strongest filtering, may necessarily have a weaker potential to promote species coexistence across the plot. The weak spatial variation in filters with strong effects on demography may result from long-term processes affecting the species pool that favour habitat generalist strategies.

Serpentine-derived soils have high concentrations of Cr and Ni from the parent materials and pose a risk to human health and environmental quality. The use of pXRF is a viable and effective technique for digital soil morphometrics. Soil digestion by aqua regia (AR) is a common method for screening heavy metals in contaminated soils. To provide in situ measurements, pXRF was performed for quantifying Cr and Ni in 49 soil horizons from 11 pedons at 3 serpentine areas in eastern Taiwan. Cr and Ni were also determined by the AR method for the samples. The correlation between pXRF and AR methods was linear and significant (r = 0.90 and 0.99, respectively, P < 0.001). The metal contents by pXRF were, however, higher than by AR. The difference is much larger for Cr than for Ni, because Cr was mainly fixed in the chromite minerals which were resistant to the AR reagent, but Ni was easily released from weatherable serpentine silicates. When additional 192 surface soil samples were used, the correlation was significant for Cr and Ni (r = 0.89 and 0.98, respectively, P < 0.001, n = 241). It was concluded that the pXRF was valid to rapidly screen Cr and Ni levels in serpentine soils in the field.

The phenotypic responses of human bone marrow mesenchymal cells (hBMSCs) on different ratio of chitosan/polycaprolactone (PCL) blends were investigated in this study. The results showed that hBMSCs existed different morphology on chitosan/PCL blends due to the different adhesion characteristic of cell on neat PCL and neat chitosan. Interestingly, comparing to hBMSCs on neat PCL, hBMSCs aggregated to form spheroid and to express ascendant trend of transforming growth factor β1, collagen type II, collagen type X, and Sox9 mRNA on the chitosan/PCL blended substrates with the decrease of PCL content. To confirm chondrogenesis of hBMSCs with spheroid on test substrates, Alcian Blue and Safranin O staining were used to detect the cartilaginous extracellular matrix (ECM). It revealed hBMSCs with spheroid on neat chitosan and 10 wt % PCL did turn to chondrogenic differentiation and synthesize cartilaginous ECM. Therefore, these findings provided new insights into the role of chitosan/PCL blended material could mediate the endogenous gene expression of hBMSCs to alter the phenotypic behavior through mediating the cell shape. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A:3344–3352, 2012.

Phosphors of SrAl2O4:Eu2+, Dy3+ were encapsulated with polyethylene plastic film by a physical technology. Water resistance measurements, Fourier transform infrared spectroscopy (FT-IR), thermogravimetric (TG) analysis, and photoluminescence (PL) spectrophotometry were used to characterize the phosphors Results showed that the encapsulated layer was a thin film with an encapsulation amount of 4.0 wt%, and encapsulation can effectively improve the water-resistance for the phosphor without any destroy of crystal structure of phosphors.

A new afterglow green phosphor of Zn2SiO4: Mn2+, Zr4+was prepared by high temperature solid-state method. Effects of various preparation techniques on the crystal characteristics, luminescent properties and afterglow performance have been investigated systematically. The phosphor powders were further investigated by photoluminescence excitation and emission spectra (PL) and brightness meter. The results showed that the PL of Zn2SiO4: Mn2+, Zr4+was observed in the green region due to transitions from the4T1g(G) to the5A1g(S) configuration of the Mn2+ions. This phosphor showed obvious long-lasting phosphorescence that could be clearly seen with naked eyes in a dark room for more than 2h after the irradiation source has been removed. The possible mechanism of this phosphor was also investigated based on the TL measurements.

A novel red long persistent phosphor of Sr2ZnSi2O7: Eu3+, Lu3+ was successfully synthesized with sol–gel method. Its properties were systematically characterized by X-ray diffraction(XRD), luminescence, afterglow decay curves and thermoluminescence (TL) spectra. The red phosphor showed one emission peak at 616.9nm, which is attributed to the typical 5D0–7F2 transition of Eu3+ ions as luminescent centers in Sr2ZnSi2O7 host. Lu3+ as a sensitized ion played an important role in enhancing the long afterglow performance of Sr2ZnSi2O7: Eu3+, Lu3+. Under UV light irradiation, this phosphor showed obvious red long-lasting phosphorescence that can be clearly seen with naked eyes in a dark room for over 20s after the irradiation source has been removed. Thermoluminescence (TL) measurement showed that Lu3+ co-dopan can reduce the trap depth of the title phosphor to obtain suitable ones.

Focused on environment parameters information of large dead-time and inertia, in this paper, the multi-parameters monitoring system of low-power wireless communication technology based on ZigBee CC2430 was designed. System uses a star topology network. By placing network nodes in monitoring area, the monitoring center collects monitoring information to achieve data analysis and management. The realization mathod of wireless nodes and data transmission and communications is presented. Experimental result shows that the performance of this system is quite stable and could be widely used for automatic monitoring in other environment places.

The reported complication rates of the distal radius fractures vary widely from 6% to 80%. Unlike damage to neural and tendinous structures, vascular complications have been extremely rare. We described an unusual case of distal radius fracture complicated with digital gangrenes because of occlusion of radial and ulnar arteries.

A novel red long-lasting phosphor CaAl2Si2O8:Mn2+ was successfully synthesized by sol-gel method. X-ray diffractometer(XRD) and fluorescence spectrometer were used to characterize the structure and photoluminescence of the persistent phosphors, respectively. Under UV light irradiation, this phosphor showed obvious long-lasting phosphorescence that can be clearly seen with naked eyes in a dark room for 18 min after the irradiation source has been removed. Thermoluminescence measurement showed that the phosphor has an appropriate energy depth of 0.43 ev.

The problems of stochastic stability and robust reliable sliding mode H∞ control for a class of nonlinear matched and mismatched uncertain systems with stochastic jumps are considered in this paper. A more practical model of actuator failures than outage is considered. Based on the state feedback method, the resulting closed-loop systems are reliable in that they remain robust stochastically stable and satisfy a certain level of H∞ disturbance attenuation not only when all actuators are operational, but also in case of some actuator failures. The uncertain system under consideration may have mismatched norm bounded uncertainties in the state matrix. The transition of the jumping parameters in the systems is governed by a finite-state markov process. A sufficient condition is given for the existence of integral sliding surface in terms of linear matrix inequalities (LMIs). Then, a reaching motion controller is designed such that the resulting closed-loop system can be driven onto the desired sliding surface in finite time. Moreover, a state feedback controller is also constructed by using the solution of LMIS. Finally, we give a design example in order to show the effectiveness of our method.

The accumulation and effect of cadmium (Cd) on the growth and enzymatic activities changes of antioxidants in Tagetes patula, French marigold, were investigated to reveal the physiological mechanisms corresponding to its Cd tolerance and accumulation. Hydroponically grown T. patula plants were treated with different concentrations of Cd (0, 10, 25, 50 μM Cd Cl(2)) at various regime of times. T. patula accumulated Cd to a maximum of 450 mg Cd kg(-1) dry weight (DW) in shoot and 3500 mg Cd kg(-1) DW in root after 14 days' exposure at 10 and 50 μM Cd Cl(2), respectively. The translocation factors of Cd were greater than 1 in plants exposed to 10 μM Cd Cl(2). Toxic effects were gradually observed with increasing Cd concentration (25 and 50 μM) accompanied with the reduction of biomass, chlorophyll content, decrease of cell viability and the increase level of lipid peroxidation. In leaves of T. patula, the activities of ascorbate peroxidase (APX), glutathione reductase (GR) and superoxide dismutase (SOD) were induced by Cd. However, in roots, activities of APX, GR, SOD and catalase (CAT) were significantly reduced by 25 and 50 μM Cd treatment but not 10 μM Cd. In-gel zymography analysis revealed that Cd induced the enzymatic activities of APX, MnSOD, CuZnSOD and different isozymes of GR in leaves. These results indicate that T. patula is a novel Cd accumulator and able to tolerate with Cd-induced toxicity by activation of its antioxidative defense system.

Despite being a major domain of global food supply, rice–wheat cropping system is questioned for its contribution to carbon flux. Enhancing the organic carbon pool in this system is therefore necessary to reduce environmental degradation and maintain agricultural productivity. A field experiment (November 2002–March 2006) evaluated the effects of soil management practices such as tillage, crop residue, and timing of nitrogen (N) application on soil organic carbon (SOC) sequestration in the lowland of Chitwan Valley of Nepal. Rice (Oryza sativa L.) and wheat (Triticum aestivum L.) were grown in rotation adding 12 Mg ha−1 y−1 of field-dried residue. Mung-bean (Vigna radiata L.) was grown as a cover crop between the wheat and the rice. Timing of N application based on leaf color chart method was compared with recommended method of N application. At the end of the experiment SOC sequestration was quantified for five depths within 50 cm of soil profile. The difference in SOC sequestration between methods of N application was not apparent. However, soils sequestered significantly higher amount of SOC in the whole profile (0–50 cm soil depth) with more pronounced effect seen at 0–15 cm soil depth under no-tillage as compared with the SOC under conventional tillage. Crop residues added to no-tillage soils outperformed other treatment interactions. It is concluded that a rice–wheat system would serve as a greater sink of organic carbon with residue application under no-tillage system than with or without residue application when compared to the conventional tillage system in this condition.

Chelate-induced phytoextraction is an innovative technique for cleaning metal- contaminated soil. The present study evaluates the degree of metal mobilization in soil and enhancement of phytoextraction of cadmium (Cd), lead (Pb), and zinc (Zn) by Sesbania sesban (L.) Merr. from artificially contaminated soil by application of ethylenediaminetetraacetic acid (EDTA). After 30 days of plant growth, the pots were divided into three sets (0.0, 2.5, and 5.0 mmol EDTA per kg soil). Experimental results indicated that levels of diethylenetriaminepentaacetic acid (DTPA)–extractable metals and metals in the leachate decreased as the EDTA dose increased. Plant growth parameters and total chlorophyll contents in the plants with EDTA applied were less than those of control. However, EDTA application significantly reduced metal accumulation in root and increased metal accumulation in the shoot of plants; similar results were obtained for the bioconcentration factor and translocation factor. The application of 5 mmol ED...

Dissolved organic carbon (DOC) can affect the mobility or bioavailability of heavy metals in a soil system. We investigated the effects of two compost-derived DOC solutions on the release of Cd, Zn, and Cu from two metal-spiked agricultural soils via repeated extraction experiments under acidic conditions. The two soils used in this study were acidic (pH 5.1-5.7) and differed primarily in soil texture (Sankengtzu [Sk] sandy loam vs. Potu [Pu] silty clay loam). The soils were spiked with individual metals (Cd, Zn, or Cu) to levels close to the limits imposed by local regulations. The metal-spiked soils were treated with two acidified DOC solutions (10 mmoUL DOC; pH 3; Na + exchanged), one derived from sewage sludge compost and the other from swine manure compost, followed by repeated extraction experiments. The results showed that the addition of DOC in the extraction solution can accelerate the acidification and the release of Cd, Zn, and Cu from the two soils. This effect was more obvious for the Sk sandy soil than for the Pu clay soil. The two DOC solutions, which were extracted from different sources, showed different behaviors of metal release. The differences might be related to the acid strength, metal-binding strength of acid sites, and the presence of other anions. The release of Cd from the soils was controlled mainly by the pH of the soil. Neither an inhibition effect of chloride ions nor an improvement effect of DOC on the Cd release was found. The release of Zn was slightly inhibited (~10%) by the DOC solution extracted from the sewage sludge compost (or Neihu secondary sludge compost [NH2SC]-DOC), especially from the Sk sandy soil, which was assumed to be the result of the formation of sulfide. The use of DOC extracted from the swine manure compost (or SMC-DOC) can result in the release of more Cu (up to 35%-40%) from both soils. The DOC solutions can be used for enhancing the efficiency of acid-washing techniques used for metal-contaminated soil remediation (especially for Cu).

A site in central Taiwan with an area of 1.3 ha and contaminated with Cr, Cu, Ni, and Zn was selected to examine the feasibility of phytoextraction. Based on the results of a preexperiment at this site, a total of approximately 20,000 plants of 12 species were selected from plants of 33 tested species to be used in a large-area phytoextraction experiment at this site. A comparison with the initial metal concentration of 12 plant species before planting demonstrated that most species accumulated significant amounts of Cr, Cu, Ni, and Zn in their shoots after growing in this contaminated site for 31 d. Among the 12 plant species, the following accumulated higher concentrations of metals in their shoots; Garden canna and Garden verbena (45-60 mg Cr kg(-1)), Chinese ixora and Kalanchoe (30 mg Cu kg(-1)), Rainbow pink and Sunflower (30 mg Ni kg(-1)), French marigold and Sunflower (300-470 mg Zn kg(-1)). The roots of the plants of most of the 12 plant species can accumulate higher concentrations of metals than the shoots and extending the growth period promotes accumulation in the shoots. Large-area experiments demonstrated that phytoextraction is a feasible method to enable metal-contaminated soil in central Taiwan to be reused.

Many studies have been conducted on phytoextraction; however, non-native hyperaccumulator species are not suitable for the natural environment of Taiwan in many cases. Drawing upon previous results, the growth and heavy metal accumulation in artificially cadmium-contaminated soils were compared for five local garden flower species. The treatments included a control (CK), 9.73 +/- 0.05 mg kg(-1) (Cd-10), and 17.6 +/- 0.8 mg kg(-1) (Cd-20). All plants were harvested at 35 days after transplanting and analyzed for Cd content. Cd accumulation in the shoot of French marigold (Tagetes patula L.) and Impatiens (Impatiens walleriana Hook. f.) grown in Cd-20 treatment were 66.3 +/- 6.5 and 100 +/- 11 mg kg(-1), which equated to a removal of 0.80 +/- 0.11 and 0.60 +/- 0.37 mg Cd plant(-1), respectively. The maximum Cd accumulation of Impatiens reached the threshold value (100 mg kg(-1)) characteristic of a Cd hyperaccumulator and its bioconcentration factor (BCF) and translocation factor (TF) were greater than one. Impatiens therefore has the potential to hyperaccumulate Cd from Cd-contaminated soils. With the exception of Garden verbena, significant relationships were found between Cd concentrations in soil extracted by 0.05 M EDTA, 0.005 M DTPA, and 0.01 M CaCl2 and the concentration of Cd in the shoots of the tested garden flowers.

Th e Coastal Range in eastern Taiwan is characterized by rapid uplift at a rate of about 5 mm yr −1 because of active arc-continent collision since the Mio-Pliocene. Th e Coastal Range includes three main levels of Holocene marine terraces, labeled the fi rst, second, and third levels descending to the coast. Th e soils that have developed on the terraces provide a chronosequence for pedogenic studies. Th irteen soil pedons formed from conglomerate associated with tuff were sampled along three transects in the central and southern part of the eastern coast of Taiwan near the localities of Chang-Bin, Cheng-Gong, and Du-Lan. Th e soils of the oldest terrace (fi rst level) are mainly Typic Hapluderts with one Typic Hapludoll; the soils of the intermediate terrace (second level) are Vertic or Typic Hapludolls; and the soils of the youngest terrace (third level) are Typic Udipsamments. Th e degree of development of these soils can be determined from horizon index (HI), weighted profi le development index (WPDI), weighted mean profi le (WMP) clay, WMP silt, WMP sand, and WMP cation exchange capacity with correlation coeffi cients (r) >0.6 by linear or logarithmic functions. Comparisons of the chronofunctions based on WMP clay data in subtropical and Mediterranean climates suggest that climatic conditions not only control weathering intensity but also infl uence rates of soil development. Th e pedogenic evidence in this study supports the correlation of terraces suggested by previous geomorphic and tectonic studies. Th e anomalous, relatively weaker degree of soil development on the oldest terrace at Du-Lan supports the conclusion that uplift rates in the Du-Lan area are greater than at Chang-Bin and Cheng-Gong.

Our previous study has illustrated that chitosan could enhance human anterior cruciate ligament (ACL) cells to exhibit a dramatic effect on increasing the gene expression of transforming growth factor beta1 (TGF-beta1), which is a specific gene for wound healing and collagen synthesis. However, human ACL cells could not adhere and proliferate well on chitosan. In order to overcome this drawback, we introduced polycaprolactone (PCL) into chitosan by the method of blending in this study. It was found that the morphology, viability and gene expression of human ACL cells on the chitosan/PCL blends could be effectively regulated. With the increase of PCL content in blends, human ACL cells presented more flatten shape, well-organized cytoskeleton, and higher proliferated ability. Compared to flatten shape, human ACL cells with round shape exhibited higher levels of mRNA expression of TGF-beta1 and collagen type III through 3-day culture period. Furthermore, these blended materials could upregulate protein synthesis of human ACL cells, which corresponded to their gene expressions. Therefore, it is possible to combine the advantages of chitosan and PCL to create a new blended material, which could control cellular morphologies specifically, and further to regulate the gene expression and protein production of cells for specific applications. We expected this concept, controlling the cell shape through biomaterial to modulate the behavior of cells, could provide a new vision for the material selection of ligament tissue engineering.

SSSAJ: Volume 74: Number 3 • May–June 2010 Soil Sci. Soc. Am. J. 74:880–891 Published online 19 Mar. 2010 doi:10.2136/sssaj2009.0020 Received 15 Jan. 2009. *Corresponding author (soilchen@ntu.edu.tw). © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher. Hydropedological Implications of Ferromanganiferous Nodules in Rice-Growing Plinthitic Ultisols under Different Moisture Regimes Pedology

The purpose of this study is to provide preliminary data on chloride diffusion of lightweight aggregate concrete containing crushed stone-powder. Accordingly, the study performed experiments using concrete aggregates of Crushed Aggregate (CG), Single-sized Lightweight Aggregate (SLG), Continuous Graded Lightweight Aggregate (CLG), and using water-binder ratio of 0.4, 0.5, 0.6, and using binder of FA and BFS. The chloride diffusion coefficient is calculated according to the NT BUILD 492. Diffusion coefficient of SLG and CLG were higher than that of CG concrete, but the difference was not significant. Also, chloride diffusion coefficient data indicated that it was highly affected by water-binder ratio, and it decreased with the decrease in waterbinder ratio. The admixture substitution of FA15% was effective in decreasing the diffusion coefficient only with water-binder ratio of 0.4 while admixture substitution of FA10+BFS20% was effective with all levels of water-binder ratio. The result of study shows lightweight aggregate concrete containing crushed stone-powder has slightly higher chloride diffusion coefficient than CG concrete, but the difference is not significant such that it can be overcome by adjusting water-binder ratio and admixture substitution. In addition, the data indicate the chloride diffusion coefficient of lightweight aggregate concrete can be estimated from the strength of lightweight aggregate.

Measurements of soil nitrogen (N) transformation rate are needed to be able to assess the plant availability and forest ecosystem losses of N, but little is known about lowland subtropical rainforests. The objectives of the present study were to determine the rates of N mineralization and nitrification in different seasons (January and August 2006) and in different landscape positions (footslope and summit) in the Nanjenshan forest of southern Taiwan, where vegetation types and soil properties vary among different landscape positions. Net N mineralization and nitrification were measured using 28-day in-situ open core and capped core incubations. The results from January 2006 showed that the concentrations of ammonium-N (NH4 +-N), mineral N (NH4 +-N plus NO3 −-N) and nitrate-N (NO3 −-N) were not significantly different between open and capped cores, or between summit and footslope. However, the results of August 2006 showed that the NH4 +-N concentrations of the summit soils were significantly hig...

Andisols have been shown to evolve over time to other, more weathered soil types. However, more information is needed on the time-scales over which these changes occur under different climatic conditions. In this study, we analyze mineral weathering and soil formation along a soil climosequence formed on volcanic deposits of > 400 ka of age in the subtropical climate of Northern Taiwan. We sampled 6 pedons at elevations between 140 and 1090 m above sea level (asl), representing a climatic gradient from about 22 °C mean annual temperature (MAT) and 2000 mm mean annual precipitation (MAP) to about 16.5 °C MAT and 5000 mm MAP. Our results show that phosphate retention, Al o + 1/2Fe o , Si o and the Fe o /Fe d ratio significantly increased with elevation. The high-elevation soils (> 900 m asl) contained metastable poorly crystalline materials (e.g. allophane, ferrihydrite) and classified as Andisols, whereas the low-elevation soils (

The Tadu tableland is located at the deformation front of the Western Foothills in central Taiwan. The surface of the tableland is covered by reddish soils and gravels, and is folded symmetrically with gently dipping strata running toward both wings. Previous geomorphic studies suggested a fluvial terrace landform developed on the surfaces of the tableland. However, other suggestions have been proposed in recent years. This study attempts to solve the argument by examining the pedogenesis of surface deposits. Five soil pedons were sampled to the depths of C horizons in the surface deposits of the tableland. Strong migration of illuvial clay was indicated by the accumulation of significant clay coatings in the sub-surface soils. These soils were classified as Paleudult and Kandiudult of Ultisols according to Soil Taxonomy. In addition, their morphological characteristics were further quantified in terms of soil development by the horizon index and weighted profile development index (WPDI). The WPDI values of 0.64–0.73 for the soils of the Tadu tableland agree with those of Ultisols developed on the Pakua tableland. Both qualification and quantification assessments indicate all soils of the Tadu tableland are equivalent in terms of degree of pedogenesis. As a result, all the geomorphic surfaces on the tableland probably developed at the same time, which rules out the interpretation of fluvial terraces developing on the tableland. The pedogenic evidence conditionally supports the recently proposed kinematic model for the development of the Tadu tableland.

Rice is one of the most important staple foods worldwide. Soil contamination with heavy metals and food safety problems occur in many countries as a result of numerous human activities, particularly wastewater and solid waste disposal. This review paper provides a schematic summary of heavy metals in identification processes, transport in soil to different rice varieties, and soil remediation strategies and techniques surrounding the agro-environmental impact in paddy soils based on a description of Taiwan’s experiences and database. In terms of the soil control standard, heavy metals including As, Cd, Cr, Cu, Hg, Ni, Pb and Zn are regulated by the Soil and Ground ater Pollution Remediation Act of Taiwan. Owing to the heavy metal source from wastewater along irrigation systems, heavy metals not only accumulate in the surface soil (0–30 cm), but are also highly distributed at the main entrance of irrigation water into individual paddy fields. Moreover, sediments in the irrigation canal have to be ...

Soil properties may affect the decomposition of added organic materials and inorganic nitrogen (N) production in agricultural soils. Three soils, Potu (Pu), Sankengtzu (Sk) and Erhlin (Eh) soils, mixed with sewage sludge compost (SSC) at application rates of 0 (control), 25, 75 and 150 Mg ha−1 were selected from Taiwan for incubation for 112 days. The aim of the present study was to examine the effects of SSC application rates on the carbon decomposition rate, N transformation and pH changes in three soils with different initial soil pH values (4.8–7.7). The results indicated that the highest peaks of the CO2 evolution rate occurred after 3 days of incubation, for all treatments. The Pu soil (pH 4.8) had a relatively low rate of CO2 evolution, total amounts of CO2 evolution and percentage of added organic C loss, all of which resulted from inhibition of microbial activity under low pH. For the Pu and Sk soils, the concentration of NH4 +-N reached its peak after 7–14 days of incubation, which indi...

In this study, concentrations of nickel (Ni) were quantified in the soils and plants in the agricultural areas of Salcedo watershed in Eastern Samar Island, Philippines. The quantity of total Ni in soils (TS-Ni) was significantly high with a mean of 1,409 mg kg(-1), while the soil available Ni (SA-Ni) was low with a mean of 8.66 mg kg(-1). As the levels of TS-Ni in the Salcedo watershed greatly exceeded the maximum allowable concentrations for agricultural soils, the site is not suitable for agricultural purposes. Despite significant TS-Ni levels, SA-Ni levels were very low due to tight binding between Ni and soil components. Consequently, all plants investigated did not meet the criterion for a Ni hyperaccumulator plant with low Ni contents (mean TP-Ni of 14.7 mg kg(-1)). Comparison of Ni levels between food plants and its recommended daily intake (RDI) suggests that consumption of food-plants grown in the study area is unlikely to pose health risks. However, caution must be taken against combined consumption of food plants with high Ni levels or their prolonged consumption, as it can induce accumulation of Ni above RDI.

Soils contaminated with metals are a serious problem in central Taiwan; 70% of the metals-contaminated soils in Taiwan are distributed there. We used soil turnover and dilution methods to reduce the total concentration of metals in soil, but this technique may be not suitable for other sites because of their shallow soil depths, which were less than 60 cm. Central Taiwan has the largest flower market in Taiwan and we propose that using local flower species to clean up the metals-contaminated soils is a feasible solution. A 1.3-ha area contaminated by multiple metals (As, Cr, Ni, Cu, and Zn) located in central Taiwan was selected for this large-area phytoremediation experiment. According to the Taiwan Environmental Protection Administration project contract, in-situ selection experiments were conducted to select 12 potential species from 33 tested species for further large area experiment. After in-situ planting of 33 species of plants in the contaminated soil for 33 d, bougainvillea and cockscomb showed y...

Feitsui reservoir, the major water supply of Taipei city, has shown declining water quality in recent years. The reservoir is located in an area famous for tea cultivation, and the question arises as to whether the hillside tea plantations have contributed to increased sediment and nutrient discharge into the reservoir. In this study, soil and phosphorus redistribution were examined along a steep tea plantation in the reservoir's catchment and the provenance of reservoir sediment was assessed. Fallout radionuclides were used as soil erosion/deposition tracers and as markers of sediment sources. Continuous fertilizer application has raised (inorganic) phosphorus levels in the studied tea plantation. The plantation's narrow bench terraces trap eroded material and slow down soil and nutrient translocation. Nevertheless, eroded soil and phosphorus have accumulated on a vegetated toeslope below the tea plantation. The reservoir sediment contained significant amounts of inorganic phosphorus and cesium-...

Most of the metals-contaminated and fallow lands in Taiwan are a result of irrigation with illegal effluent of factories. Phytoextraction methods can be applied to reach the target of fallow-lands reuse and earn more incomes for farmers. In many studies, Indian mustards (Brassica juncea) were planted in the metal-contaminated soils to study their suitability in phytoextraction. However, the total removal of metals by plants was quite different between accessions. In this pot study, three accessions of B. juncea (cv. 182921, cv. 211000, and cv. 426308) were planted in artificially Cd- or Pb-contaminated soils to investigate the differences between them. EDTA was applied to study its effect in increasing the bioavailability of Cd and Pb and their uptake by these Indian mustards. Experimental result showed that three accessions of Indian mustard can accumulate a high concentration of Cd and Pb when growing in the artificially Cd- and Pb-contaminated soils. Their shoot Cd or Pb concentrations were significantly enhanced, resulting from the application of EDTA. Among the three accessions, B. juncea cv. 211000 accumulated the highest concentrations of Cd and Pb in their shoots compared with B. juncea cv. 182921 and cv. 426308, but its total removal was the lowest due to its lower biomass.

Soil chronosequences developed on elevated marine terraces are ideal for studying changes in soil-forming processes with time. The coastal range of eastern Taiwan is a product of active arc–continent collision. Vertisols, Mollisols and Entisols are generally found on the different levels of marine terraces herein, but no detailed investigations of soil chronosequence have been conducted by integrating field morphology, physio-chemical characterization, micromorphology and mass-balance interpretations. Five soil pedons were selected on the three marine terraces including Tt-1 and Tt-2 pedons (Typic Hapluderts) on the first higher level with the oldest soil age (9–10 ka), Tt-3 (Vertic Hapludolls) and Tt-4 pedons (Typic Hapludolls) on the second intermediate level (5–6 ka), and Tt-5 pedon (Typic Udipsamments) on the third lower level with the youngest soil age (≤ 3.5 ka). The morphological characteristics showed that strongly developed angular blocky structures, pressure faces and slickensides are more common in higher terrace soils than in lower terrace soils. In this study, depth to C horizon, solum thickness, and thickness of the clay-enriched zone increase with relative terrace age. Although only one to two profiles per terrace were characterized, the following soil analytical characterizations increase with time: the degree of sand grains weathering, pH (H2O), organic carbon, CEC, contents of Fed, Feo and Mnd. Based on X-ray diffraction analysis of the clay-size fraction, soils on all terraces have a mixed mineralogy. Mica, smectite, and kaolinite have slightly increased with increasing terrace age. Furthermore, the dominant processes identified with mass-balance analysis include loss of bases (Ca and Mg), iron, and clay with time. The soil properties, including analytical and mineralogical characterizations, which do not have notable changes with time are primarily due to relatively young soil age (

This study examines the relationships between topography and spatial variations in groundwater and soil morphology within the multi-step Taoyuan–Hukou Tableland in northwest Taiwan. Several different geomorphological and pedological approaches were jointly undertaken, including analyses of a digital elevation model (DEM), a reclassified soil map, field survey results, engineering borehole data, and a hydrological simulation. Five major geomorphic surfaces were identified based on terrace scarps observed in the DEM; minor surfaces separated by small fluvial scarps or tectonic scarps were also mapped. The simplified soil map and field study of soil morphology reveal a number of soil-distribution patterns associated with specific topographic settings. Soil morphology changes from homogeneous red soils in the fore-edge of surfaces to mottled soils and finally to gley soils in back-edge regions. Such a pattern is more pronounced in the proximal part of a surface, while toward the distal zone the patterns tend to be obscured by increasing amounts of mottled and gley soils. The proportion of homogeneous soils increases with narrowing of the surface. For fan-shaped surfaces, soil types appear to be dominated by mottled soils except for at terrace edges, where homogeneous red soils occur. While homogeneous soils dominate tectonically elevated surfaces, a toposequence of homogeneous-mottled-gley soils occurs in the surrounded lowlands. Borehole data and hydrological models indicate that these soil-distribution patterns are strongly related to groundwater occurrence and fluvial processes, both of which are generally governed by topography. Despite the observed pedodiversity in this area, the common feature of these toposequences, i.e., the distribution of homogeneous red soils along the surface fore-edge, may serve as a basis for establishing a reliable soil chronosequence for the area.

Synthetic chelating agents are used to increase the phytoextraction of metals from contaminated soils, however the increased bioavailability of the metals may increases the potential risk of groundwater contamination. In this study, 4 mmol EDTA kg−1 was applied using four application methods to a Cd-, Zn-, and Pb-contaminated soil to evaluate the effects of multi-dose EDTA application on the metals concentrations in the soil solution, soil (as extracted by different methods), and shoots of rainbow pink (Dianthus chinensis). Results showed that application of 4 mmol kg−1 one time or application of 2 mmol kg−1 two times, significantly decreased the concentration of Cd, Zn, and Pb in the soil solution at the end of experiment (42nd day) compared with the application of 0.67 mmol kg−1 six times during 6 weeks experiments. Application of 2 mmol kg−1 two times significantly decreased the deionized water-extractable Cd and Pb concentrations in the soil compared with the application of 0.67 mmol kg−1 six times. However, there were no any effects of the different application methods on the concentration and total removal of Cd, Zn, and Pb in the shoots of rainbow pink. Results revealed that application of 2 mmol kg−1 two times was effective to decrease the potential groundwater contamination.

Until now, the mineral nutrition of rain forest trees is still poorly understood. Very few data are available on the nutrient characteristics of rain forest tree species and the influence of environmental factors especially for subtropical climates. This study evaluated the mineral nutrient status of the dominant tree species and its relation to environmental factors such as elevation, slope, landscape position, and soil nutrient status in a subtropical rain forest of southern Taiwan. Leaf, stem, and wood samples were collected for nutrient analysis from a total of 639 trees belonging to 20 dominant species from 27 contiguous 20 m × 20 m quadrants along an altitudinal transect ranging from 300 to 480 m. Composite soil samples were likewise collected from the 0–5 and 5–15 cm depths in the A horizon in each quadrant for chemical analysis. Soils in the study site ranged from well-developed, acidic with clayey subsoil Typic Paleudult in summit positions, to poorly developed and acidic Typic Dystrudept in backslope positions. Results revealed that leaf nutrient concentration was better correlated with the environmental factors than stem and wood nutrient concentrations. In addition, data showed generally wide concentration ranges for most mineral nutrients except P and Cu and most tree species were clustered at the lower end of the concentration ranges indicating they have low nutrient status. Among the macronutrients, P had the lowest and narrowest foliar concentration (0.25–2.8 g kg −1 ; mean = 0.8) while for the micronutrients, this was shown by Cu (3.88–17 mg kg −1 ; mean = 5.8). A few tree species were observed to accumulate (called “accumulator species”) some mineral nutrients like N, P, K, Ca, Mg, Cu and Zn indicating high absorption capacity for these nutrients. Foliar mineral nutrient concentration of the trees was generally correlated with the environmental factors such as elevation, topographic position, slope, vegetation type, and soil nutrient status. However, the effects were interrelated and difficult to isolate from each other although topographic position, vegetation type, and soil nutrient status appeared to be more related to the mineral nutrient concentration of the trees than the other environmental factors. In particular, plants on the footslope had generally higher concentration of N, P and K than those at the higher elevation of the upper backslope and summit. This suggests that the distribution of tree species in the study site is reflected by their foliar nutrient concentration. P appears to be the most limiting nutrient in the rain forest ecosystem studied although fertilization experiment is needed to verify the apparent P limitation.

The southern part of the Pakua tableland in Taiwan comprises a series of wide, unpaired river terraces that have as many as six altitude levels, from PK-1 (highest) to PK-6 (lowest). The terrace surfaces are covered with lateritic soils. This study described, sampled and analyzed the soils from each terrace. Soil taxonomies are Oxisol, Ultisol and Inceptisol. Soil morphological characteristics were quantified as a profile development index (PDI) to determine the degree of soil development. The chemical analyses included cation exchange capacity (CEC) and selected extraction of Fe in soils. Based on the degree of soil development, surface deposits on terrace flights form the post-incisive soil chronosequence, supporting the hypothesis of terrace formation by fluvial processes. Soil ages were estimated based on iron crystallinity (Fed–Feo)/Fet. Analytical results indicate that river terraces in the Pakua tableland are aged 40–400 ka. The long-term uplift rate of the tableland can be estimated using terrace ages and folding geometry. The variation of uplift rates demonstrates that the landscape underwent increased shortening of frontal thrusting by the Changhua Fault running beneath the tableland.

Dihydroartemisinin (DHA) exhibits anticancer activities in a variety of cancer cells, but DHA alone are not effective enough for cancer therapy. In this study we found the stress-regulated protein p8 was obviously increased after DHA treatment in several cancer cells, which further to induce autophagy by the upregulation of endoplasmic reticulum stress-related protein ATF4 and CHOP. Furthermore, when we silenced p8 by siRNA in cancer cells, the apoptosis induced by DHA were notably increased, whereas the overexpression of p8 in cancer cells leaded to the resistance to DHA-induced apoptosis. Moreover, we found the inhibition of autophagy with chloroquine (CQ) can enhance the anticancer effect of DHA both in vitro and in vivo. In conclusion, we found that p8-mediated autophagy attenuates DHA-induced apoptosis in cancer cells, which provides evidence to support the use p8 as a cancer therapeutic target, and suggests that the combination treatment with DHA and autophagy inhibitor might be an effective cancer therapeutic strategy.

Landscapes associated with Oxisols and Ultisols in Taiwan are stable and old, measured in hundred thousands of years, and the thickness can be up to 5 m. Plinthite may be present resulted from alternative wet and dry cycles by fluctuating water tables. However, plinthite only occurs in the Ultisols with seasonal high water tables on the Quaternary terraces of aged alluvium in northern and central Taiwan, particularly on paddy rice fields. Oxisols of Taiwan are generally well-drained and have no plinthite. Only three soil series of agricultural land have been confirmed as Oxisols in Taiwan, which are always for tea or pineapple production in land use. Ultisols are about 9.6 % (1,624 km2) of the rural soils in Taiwan, while Oxisols are only

Biosolids can enrich the contents of organic matter and nutrients in soils, consequently improving the growth of plants. In order to enhance the transpiration rate and therefore the upward movement of Cd from the soil to the shoots of a potential hyperaccumulator, rainbow pink (Dianthus chinensis), different amounts of biosolid were applied to potted Cd-contaminated soils, and their effects on the leaf area were assessed. Experimental results show that the dry weight of rainbow pink was not significantly affected by the treatments of Cd and biosolid. However, the leaf area and transpiration rate in the biosolid treatments significantly increased compared with the control. There was also a linear relationship between the leaf area and the transpiration rate.

Taiwan is located at the convergent boundary between the Philippine Sea plate and the continental margin of the Eurasian plate, which covers 36,000 km2 in area; however, there are more than 200 peaks over 3,000 m in altitude, whose geographical environment supports a rich fauna, flora, and biological diversity. There are over 4,000 vascular plant species and a spectrum of six forest types in the area. The climate is characterized by high temperature and humidity, substantial rainfall, and tropical cyclones in summer, alternated with the cool and dry condition of winter. The complex environment in Taiwan develops a wide variety of soils on the surfaces over the island. The soils in Taiwan consist of 11 of the 12 soil orders (except for Gelisol) in Soil Taxonomy. The various landforms and vegetation provide an excellent and convenient opportunity for studies on soil formation. There are five climatic regions in the main island of Taiwan, according to the Koppen classification system. In the case of soils affected by human activity in large-scale farming, the anthropogenic processes have been created in Taiwan for approximately 400 years, particularly based on puddling surface soils for paddy rice production. A total of 620 soil series in Taiwan rural soils can be classified into nine soil orders based on Soil Taxonomy. Also, nine soil orders were classified into this 620 soil series in Taiwan forest soils.

Soil used in this study was artificially contaminated with Cd, Zn, Pb, or applied in combinations (Cd-Zn, Cd-Pb, Zn-Pb, or Cd-Zn-Pb) to study the interactions of metals in soil contaminated with multiple metals. After planting rainbow pink (Dianthus chinensis) in these soils for 21 days, three different concentrations of ethylenedinitrilotetraacetic acid (EDTA) solutions were added to study the effect of applying EDTA on the interactions among these metals. The concentrations of Cd, Zn, and Pb in the soil solutions of different metals-treated soils increased significantly after applying 5 mmol EDTA kg(-1) soil (p0.05). The potential of groundwater contamination will increase after applying EDTA and it is not recommended to be in situ used or have to use very carefully. The existence of Pb in the Cd-contaminated soil enhanced the uptake of Cd in rainbow pink in the treatments of control and 2 mmol EDTA kg(-1) soil. Cadmium inhibited the concentration of Zn without applying EDTA. However, whether the application of EDTA or not and the applied EDTA concentration had the greatest effect on the uptake of Pb when compared to Cd and Zn. After applying 5 mmol EDTA kg(-1) soil, Cd or Zn in the Pb-contaminated soil inhibited the uptake of Pb in rainbow pink, but there were no effect in other treatments.

Very few studies have been conducted on the nature and characteristics of soils from Quaternary limestones in geologically young islands in the humid tropics. This study examined a hillslope in Leyte, Philippines, with soils from Quaternary (Late Pleistocene) limestone and evaluated their morphology

Soil quality indices (SQI) have been proposed in recent years as tools for assessing soil management practice effects on soil quality. In this paper, we report the result of our 4-year study on the use of a SQI to assess the effects of applying swine manure compost on soil quality. Cabbage (Brassica camperstris L.) and maize (Zea mays L.) were grown in rotation in plots applied with low, medium, and high rates of swine manure compost while the control received only chemical fertilizers. Selected soil physical, chemical, and biological properties (bulk density, aggregate stability, organic carbon content, soil pH, available N, P, and K, extractable Cu and Zn, and microbial biomass), all of which were identified as possible soil quality indicators, were monitored at regular intervals. Tissues of harvested crops were analyzed for Cu and Zn concentrations because they were anticipated to increase due to the high amounts of the metals in the manure compost. A SQI model was derived based on Mausbach and Seybold’s research and on our soil database and research experience in Taiwan. Data from our manure application experiment were used to calculate the SQI values for the different treatments. Results revealed that application of swine manure compost improved the soil quality of surface soil as indicated by increased values of soil quality indicators, SQI, and yields of the crops. In addition, Cu and Zn levels in the soil and in the crop tissues did not increase to harmful levels. Thus, it seems that the SQI was an effective tool to assess the effects of swine manure compost application on soil quality. The soil indicators we found effective included the monitored properties except for bulk density. All of these soil properties were significantly increased by manure compost application. Long-term application of 40‐60 tons ha j1 year j1 of manure compost may improve the soil quality and increase the yield of the crops without polluting the soil and crops with Cu and Zn. (Soil Science 2006;171:210‐222)

Soils science and fluvial geomorphology meet on the subject about flights of river terraces whose treads rise like stairs above active channels. The Pakua tableland in central Taiwan consists of widely unpaired terraces, including six levels in altitude formed by successive river incision. The terraces serve as geomorphic markers to gauge the differential or absolute deformation of the land surface but such application is hampered by the absence of well-documented ages. Six representative soil pedons were selected from the six levels of terraces in the tableland (from the highest pedon PK-1 to lowest pedon PK-6) to characterize the soil properties in a chronosequence and to relate the pedogenic processes in the major terraces to the formation and evolution of the landscape in the study area. The soil morphological, physical, and chemical properties as well as the clay mineral variation showed that pedogenic intensity is strongly dependent on the terrace levels with varying formation age. The soils can be divided into three domains as Hapludox for pedon PK-1, Paleudult (or Hapludult) for pedons PK-2, PK-3, PK-4, and PK-5, and Dystrudept for pedon PK-6, based on Soil Taxonomy. The degree of soil development increases with altitude in a sequence from PK-1 to PK-6 forming a postincisive type of soil chronosequence in accord with the evolution of the geomorphic surface by successive river incision in the study area. Based on the crystallinity ratios of free iron, the soils give an estimated age of 40-400 ka for the river terraces of the tableland.

International audience; The natural speciation of Mn (0.19 g/kg), Ni (46 mg/kg), and Zn (42 mg/kg) in the argillic horizon (120 cm depth, pH = 5.6) of an Ultisol from a paddy soil in northern Taiwan was investigated by advanced X-ray synchrotron techniques. Microchemical associations were imaged by synchrotron-based X-ray microfluorescence, host minerals were identified by standard and micrometer-resolved X-ray diffraction, and the local coordination environment of Mn, Ni, and Zn was probed using extended X-ray absorption fine structure (EXAFS) spectroscopy on a powdered sample and a soil thin section, and polarized EXAFS spectroscopy on a highly textured self-supporting clay film from the < 2 mu m fraction of the soil. Manganese was concentrated in Fe-Mn soft mottles (44.4 g/kg) as turbostratic hexagonal birnessite and lithiophorite having Mn3+/Mn4+ atomic ratios of similar to 20% and 50%, respectively. Quantitative analysis of high-order scattering paths of the EXAFS spectrum for natural and synthetic (Al0.67Li0.32)(Mn0.684+Mn0.323+)O-2(OH)(2) lithiophorite revealed that Mn3+ and Mn4+ are ordered in the [(Mn0.684+Mn0.323+)O-2](0.32-) layer. A structural model is proposed, in which Mn4+ and Mn3+ are ordered similarly to Al and Li in the [(A(0.67)(3+)Li(0.32)(+))(OH2)O-2](0.32+) layer, with Mn3+ cations being surrounded by six Mn4+, and Mn4+ cations by three Mn3+ and three Mn. Similar cation ordering in the manganese and aluminum layers likely provides a more homogeneous local balance of the excess and deficit of charges in each layer and increases the stability of lithiophorite. Ni (r = 0.70 angstrom) substitutes for Mn (r(Mn4+) = 0.54 angstrom, r(Mn3+) = 0.65 angstrom) in the manganese layer in the natural lithiophorite. In contrast, Zn (r = 0.74 angstrom) fills vacant sites in the gibbsitic layer of natural lithiophorite, in a similar manner as lithium (r = 0.74 angstrom) in synthetic lithiophorite. The partitioning of Ni and Zn between the two layers is a result of the general preference of Ni, whose size is intermediate between those of Mn3+ and Li+, for slightly smaller sites. In contrast with nickel, which is detected only where there is lithiophorite, the Zn-lithiophorite association found in Fe-Mn mottles is not representative of the bulk soil. The combined use of X-ray diffraction, and powder and polarized EXAFS spectroscopy revealed that Zn is predominantly bound to hydroxy-Al interlayers sandwiched between 2:1 vermiculite layers in the fine soil matrix. The incorporation of Zn in the gibbsitic layer of both lithiophorite and vermiculite helps increase the stability of these minerals by providing positive charge to balance the negative charge from the 2:1 phyllosilicate layer and the [(Mn0.684+Mn0.323+)O-2](0.32-) layer of lithiophorite. This binding environment for zinc is probably the main mechanism by which zinc is sequestered in acidic to near-neutral aluminum-rich clayey soils.

Rainbow pink (Dianthus chinensis), a potential phytoextraction plant, can accumulate high concentrations of Cd from metal-contaminated soils. The soils used in this study were artificially added with different metals including (1) CK: original soil, (2) Cd-treated soil: 10 mg Cd kg(-1), (3) Zn-treated soil: 100 mg Zn kg(-1), (4) Pb-treated soil: 1000 mg Pb kg(-1), (5) Cd-Zn-treated soil: 10 mg Cd kg(-1) and 100 mg Zn kg(-1), (6) Cd-Pb-treated soil: 10 mg Cd kg(-1) and 1000 mg Pb kg(-1), (7) Zn-Pb-treated soil: 100 mg Zn kg(-1) and 1000 mg Pb kg(-1), and (8) Cd-Zn-Pb-treated soil: 10 mg Cd kg(-1), 100 mg Zn kg(-1), and 1000 mg Pb kg(-1). Three concentrations of 2Na-EDTA solutions (0 (control), 2, and 5 mmol kg(-1) soil) were added to the different metals-treated soils to study the influence of applied EDTA on single and combined metals-contaminated soils phytoextraction using rainbow pink. The results showed that the Cd, Zn, Pb, Fe, or Mn concentrations in different metals-treated soil solutions significantly increased after applying 5 mmol EDTA kg(-1) (p0.05). The metal concentrations in different metals-treated soils extracted by deionized water also significantly increased after applying 5 mmol EDTA kg(-1) (p0.05). Because of the high extraction capacity of both 0.005 M DTPA (pH 5.3) and 0.05 M EDTA (pH 7.0), applying EDTA did not significantly increase the Cd, Zn, or Pb concentration in both extracts for most of the treatments. Applying EDTA solutions can significantly increase the Cd and Pb concentrations in the shoots of rainbow pink (p0.05). However, this was not statistically significant for Zn because of the low Zn concentration added into the contaminated soils. The results from this study indicate that applying 5 mmol EDTA kg(-1) can significantly increase the Cd, Zn, or Pb concentrations both in the soil solution or extracted using deionized water in single or combined metals-contaminated soils, thus increasing the accumulated metals concentrations in rainbow pink shoots. The proposed method worked especially well for Pb (p0.05). The application of 2 mmol EDTA kg(-1) might too low to enhance the phytoextraction effect when used in silty clay soils.

To understand whether soils on the same geomorphic surface have similar properties, this study examines the morphology of soils developed on the 30-kyr-old Taoyuan Terrace, Northwestern Taiwan. Relationships among soil morphology, variations in the groundwater table, and soil forming processes were established based on field investigations and previously published datasets. The soil series in the study area can be grouped into seven types, including three homogeneous groups, two mottled groups, one gley group, and one reworked group. Fifteen hand-core samples collected in the field and borehole data were used to understand spatial variations in soil morphology. The results indicate that soil morphology on the southern Taoyuan Terrace changes systematically from the fore-edge to the back-edge: from red/orange soils to yellow soils, then to mottled soils, and finally to gley soils. The borehole data indicate that the groundwater table is generally parallel to the ground surface but drops significantly near the terrace fore-edge. This pattern matches with the observed soil toposequence, indicating that the pedogenic processes in the study area are mainly controlled by groundwater distribution determined by topography. Although soils on the terrace fore-edge have developed under the well-drained conditions that favor lateritization, at least two distinct soil types (i.e., red and orange) can be observed there, reflecting different geomorphological settings in a paleo-fluvial landscape. This work suggests that geomorphological and hydrological conditions should be examined carefully before using soil morphology for correlating geomorphic surfaces.