Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.jece.2024.114555

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Association for the Advancement of Science (AAAS)  

Rivers and streams contribute to global carbon cycling by decomposing immense quantities of terrestrial plant matter. However, decomposition rates are highly variable and large-scale patterns and drivers of this process remain poorly understood. Using a cellulose-based assay to reflect the primary constituent of plant detritus, we generated a predictive model (81% variance explained) for cellulose decomposition rates across 514 globally distributed streams. A large number of variables were important for predicting decomposition, highlighting the complexity of this process at the global scale. Predicted cellulose decomposition rates, when combined with genus-level litter quality attributes, explain published leaf litter decomposition rates with high accuracy (70% variance explained). Our global map provides estimates of rates across vast understudied areas of Earth and reveals rapid decomposition across continental-scale areas dominated by human activities.

DOI： 10.1126/science.adn1262

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.scitotenv.2024.172236

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.gsd.2024.101087

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.watres.2024.121260

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DOI： 10.1016/j.ecolmodel.2023.110605

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Spatiotemporal changes in waterborne disease risk were evaluated for the Chhnok Tru floating village in the Tonle Sap Lake by combining a hydraulic simulation and quantitative microbial risk assessment (QMRA). First, a three-dimensional (3D) hydraulic simulation was performed, and the transport of Escherichia coli (E. coli) was simulated. Prior to the simulation, by coupling satellite imagery analysis using the normalized difference water index (NDWI) and a sounding survey using an acoustic Doppler current profiler (ADCP), a new digital elevation model was generated for the complex channel network with high resolution. The results of the 3D hydraulic simulation revealed the flow regime and nonuniform pathogen distribution in the floating village. QMRA was performed for the village using the E. coli distribution calculated by the 3D hydraulic model. Subsequently, the disease risk in the village was visualized through an effective and easy-to-understand disease risk map. To demonstrate the usefulness of the hydraulic-simulation-based disease risk map, the map was used to quantitatively compare simple policies by evaluating their reduction in disease risk.

DOI： 10.3390/w15234199

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Language：English   Publishing type：Research paper (scientific journal)  

Man-made reservoirs are important for human daily lives and offer different functions, however they are contaminated due to anthropogenic activities. Dissolved organic matter (DOM) from each reservoir is unique in composition, which further determines its photo-reactivity. Thus, this study aimed to investigate the photo-reactivity of reservoir DOM in terms of the quantum yield for photo-production of singlet oxygen (Ф1O2). We sampled surface water of 50 reservoirs in Japan and determined their Ф1O2 using simulated sunlight together with bulk water analysis. Their Ф1O2 ranged from 1.46 × 10-2 to 6.21 × 10-2 (mean, 2.55 × 10-2), which was identical to those of lakes and rivers reported in the literature, but lower than those of wetland water and wastewater. High-energy triplet-state of DOM accounted for 59.4% of the 1O2 production in the reservoir water on average. Among the bulk water properties, the spectral slope of wavelength from 350 to 400 nm (S350-400) was statistically detected as the most important predictor for Ф1O2. Furthermore, the multiple linear regression model employed S350-400 and the biological index as predictors with no intercorrelations and reasonable accuracy (r2 = 0.86), while the random forest model showed a better accuracy (r2 = 0.90). Overall, these major findings are beneficial for understanding the photo-reactivity of reservoir waters.

DOI： 10.1016/j.watres.2023.120456

PubMed

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/00986445.2023.2218276

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DOI： 10.3390/photochem3020017

Web of Science

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DOI： 10.3390/land12050993

Web of Science

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Photochemical reactions widely occur in the aquatic environment and play fundamental roles in aquatic ecosystems. In particular, solar-induced photodegradation is efficient for many organic micropollutants (OMPs), especially those that cannot undergo hydrolysis or biodegradation, and thus can mitigate chemical pollution. Recent reports indicate that photodegradation may play a more important role than biodegradation in many OMP transformations in the aquatic environment. Photodegradation can be influenced by the water matrix such as pH, inorganic ions, and dissolved organic matter (DOM). The effect of the water matrix such as DOM on photodegradation is complex, and new insights concerning the disparate effects of DOM have recently been reported. In addition, the photodegradation process is also influenced by physical factors such as latitude, water depth, and temporal variations in sunlight as these factors determine the light conditions. However, it remains challenging to gain an overview of the importance of photodegradation in the aquatic environment because the reactions involved are diverse and complex. Therefore, this review provides a concise summary of the importance of photodegradation and the major processes related to the photodegradation of OMPs, with particular attention given to recent progress on the major reactions of DOM. In addition, major knowledge gaps in this field of environmental photochemistry are highlighted.

DOI： 10.1016/j.watres.2022.118236

PubMed

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/su15032082

Web of Science

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Language：Japanese   Publisher：Japan Society on Water Environment  

The ratio of electricity consumption in sewage treatment to the total electricity consumption in Japan is increasing yearly. Thus, it is important to efficiently operate sewage treatment plants considering the quality of incoming sewage. However, no study has identified how the overall quality of sewage water in urban areas relationships to its sewershed characteristics. Therefore, in this study, we analyzed data from the Tokyo metropolitan area to understand the relationship between the spatiotemporal distribution of sewershed characteristics and sewage water quality. Results indicate that biochemical oxygen demand and total nitrogen concentration are correlated to daytime population density in each sewershed, which is affected by land use. In addition, sewage water quality showed seasonal relationships to utility expenditures and monthly air temperature, indicating the temporal relationship between these sewershed characteristics and sewage water quality. In conclusion, through this study, the spatiotemporal distribution of sewershed characteristics was clarified and the relationship was identified between sewershed characteristics and sewage water quality. Results imply that the sewage water quality in the Tokyo metropolitan area can possibly be modeled on the basis of daytime population density, land use, utility expenditures and monthly air temperature, which might be beneficial for the efficient long-term operation of sewage treatment plants.

DOI： 10.2965/jswe.46.35

DOI： 10.3739/rikusui.85.87_references_DOI_HCONJ0wq3MQjHD0uDWHP52q0JDK

CiNii Research

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.chemosphere.2022.134106

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.envadv.2022.100176

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.chemosphere.2021.132318

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry (RSC)  

Monitoring bacteria is essential for ensuring microbial safety of water sources, including river water and treated wastewater.

DOI： 10.1039/d1va00017a

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Publishing type：Part of collection (book)   Publisher：Springer Nature Singapore  

DOI： 10.1007/978-981-16-6632-2_18

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s10661-021-09649-z

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Other Link： https://link.springer.com/article/10.1007/s10661-021-09649-z/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Even though wind, water depth, and shear stress are important factors governing sediment resuspension in lakes, their actual relations to total suspended solids (TSS) distribution in natural environments have not been well elucidated. This study aims to elucidate the impact of the wind on the spatio-temporal variation of TSS in Tonle Sap Lake, Cambodia, during low-water (March and June, <1 m) and high-water (September and December, 8–10 m) seasons. To this end, wind and TSS data for December 2016 and March, June, and September 2017 were collected and analyzed. For spatial interpolation of wind speed, the inverse distance weighted method was found to be better (R2 = 0.49) than the vectorized average (R2 = 0.30) and inverse of the ratio of distance (R2 = 0.31). Spatial interpolation showed that the wind speed and direction on the lake were <5 m/s and southward during the low-water season and <7 m/s and westward during the high-water season. The TSS concentration in the low-water season was higher (>50 mg/L) than that in the high-water season. The TSS concentration during the low-water season was empirically described by wind speed (W), water depth (D), and shear stress (τ_wave) with a function of W3, W3/D, and exp(W/D) or exp(τ_wave), depending on the location in the lake. The critical shear stress due to wind-induced waves at most of the places in the lake was higher than the total shear stress indicated. Sedimentation was predominant in December and June, and erosion (siltation) was dominant in March. Most of the siltation in March was dominant in the southern part of the lake.

DOI： 10.3390/earth2030025

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s11356-021-15205-6

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Other Link： https://link.springer.com/article/10.1007/s11356-021-15205-6/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IWA Publishing  

Abstract

The main objective of this research was to explore the fluorescence quenching mechanism of a humic substance (Suwannee River natural organic matter (SWNOM)) to amino acids (tryptophan, tyrosine) and protein (bovine serum albumin, (BSA)) by multi-spectroscopic methods. The locations of the peaks of tryptophan, tyrosine, and BSA from Parallel Factor Analysis were at Ex/Em 280/356 nm, 275/302 nm, and 280/344 nm, respectively. For SWNOM, two peaks appeared at Ex/Em of 240/448 nm, and 350/450 nm. Static quenching was the dominant quenching mechanism between BSA and SWNOM, whereas no quenching was observed between tryptophan or tyrosine and SWNOM. Fourier-transform infrared spectroscopy and thermodynamic calculation demonstrated that hydrogen bonding and van der Waals force are the potential binding forces of the BSA-SWNOM complex, as a result of rearrangement in the secondary polypeptide carbonyl hydrogen bonding network of BSA. This rearrangement led to the conformational change in BSA that induced quenching of BSA fluorescence by SWNOM.

DOI： 10.2166/ws.2021.103

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s11270-021-05084-5

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Other Link： https://link.springer.com/article/10.1007/s11270-021-05084-5/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

DOI： 10.1007/s11355-020-00435-6

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Other Link： http://link.springer.com/article/10.1007/s11355-020-00435-6/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IWA Publishing  

Abstract

Fluorescence quenching of proteinaceous substances by natural organic matter is a well-known phenomenon, but there are no known methods for correcting it. The main objective of this research was to develop an empirical equation to correct the fluorescence quenching of different concentrations of bovine serum albumin (BSA – 0.15, 0.25, 0.5, 0.75, 1, 1.25 μmol/L (μM)) by Suwannee river natural organic matter (SWNOM - 0,2,4,6,8,10 mg-C/L) using the fluorescence titration method. The excitation emission matrix (EEM) data were analyzed by parallel factor analysis with inner filter effect removal. With increasing SWNOM concentration, BSA peak intensity quenching was in the range 29–85%, with a linear relationship for increment of either BSA or SWNOM concentration. A higher ratio of SWNOM to BSA resulted in greater BSA peak intensity quenching. The unquenched BSA peak (BSA (RU)) is given by the empirical equation.

The calculated unquenched BSA peak intensities using the empirical equation agreed well with the actual unquenched peak values (R2 = 0.98, mean absolute error = 0.33 RU). The equation is expected to help in rapid estimation of the quenching effect of SWNOM on BSA.

DOI： 10.2166/wpt.2021.001

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.agee.2020.107123

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Photocatalytic nanofiltration (NF) membranes with enhanced flux and anti-fouling properties were prepared from a layered in situ nanocomposite of metal organic framework (i.e., UiO-66) and graphene oxide (UiO-66_GO) on a polyamide NF membrane using a pressure-assisted self-assembly method. For filtering pure water and humic acid, the composite membrane with a 10% UiO-66_GO loading (UiO-66_GO/NF-10%) showed a higher water flux (up to 63 kg/m2 h bar), flux recovery (80%), and total fouling resistance (33%) than the pristine NF membrane. Physical and chemical characterization revealed that this performance was attributed to improvements in hydrophilicity, porosity, surface smoothness, and charge repulsion. The UiO-66_GO/NF-10% composite membrane exhibited better physical stability with a relatively low mass loss (8.64%) after five washes than the membranes with mass loadings of 5 and 15 wt%. Furthermore, the UiO-66_GO/NF-10% composite membrane exhibited considerable photocatalytic activity under ultraviolet (UV) irradiation (bandgap: 3.45 eV), which reduced irreversible fouling from 20.7% to 2.4% and increased flux recovery to 98%. This study demonstrated that surface modification with the UiO-66_GO nanocomposite produced a high-flux anti-fouling photocatalytic NF membrane, which is promising for water purification.

DOI： 10.3390/catal10060711

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer International Publishing  

DOI： 10.1007/978-3-030-43484-7_26

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：EDP Sciences  

Species distribution models (SDMs) have been used to understand the habitat suitability of key species. Habitat suitability plots, one outcome from SDMs, are valuable for understanding the habitat suitability and behavior of organisms. The sample size is often constrained by budget and time, and could largely influence the reliability of habitat suitability plots. To understand the effect of sample size on habitat suitability plots, the present study utilized random forests (RF) combined with partial dependence function. And the bluegill (Lepomis macrochirus), a main exotic fish species in the Japan rivers, was selected as target species in this study. Total of 1010 samples of bluegill observations along with four environmental variables were surveyed by the National Censuses on River Environments. The area under curves was calculated after generating RF models, to assess the predictive model performance, and this process was repeated 1000 times. To draw habitat suitability plots, we applied partial dependence function to the formulated RF models, and 15 different sample sizes were set to examine the effect on habitat suitability plots. We concluded that habitat suitability plots are affected by sample size and prediction performance. Notably, habitat suitability plots drawn from the sample size of 50 greatly varied among the 1000-time iterations, and they are all different from the observations. Furthermore, to deal with the case of limited samples, we proposed a novel approach “averaged habitat suitability plot” for delineating habitat suitability plots. The proposed approach enables us to assess the habitat suitability even with a small sample size.

DOI： 10.1051/limn/2020010

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Nanocomposites of UiO-66 and graphene oxide (UiO-66_GO) were prepared with different GO contents by a one-step hydrothermal method, and their photocatalytic activities for the degradation of carbamazepine (CBZ) were investigated under ranges of GO loading, catalyst dose, initial pollutant concentration, and solution pH. The UiO-66_GO nanocomposites showed photocatalytic rate constant up to 0.0136 min−1 for CBZ degradation and its high overall removal efficiency (>90%) in 2 h. The photocatalytic rate constant over the UiO-66_GO nanocomposite was about 2.8 and 1.7 times higher than those over pristine GO and UiO-66, respectively. The enhancement of photocatalytic activity by GO was attributed to increased surface area and porosity, improved light absorption, and narrowed band gap. The composite also showed substantial recyclability and stability over five consecutive cycles of photocatalytic degradation. The experimental results indicated that O2●− and OH● are the responsible radicals for photocatalytic degradation, which helped us propose a photocatalytic mechanism for the enhanced CBZ photodegradation. This work provides a reference for the development of GO-based composite photocatalysts and expands the application of UiO-66 as a photocatalyst for the degradation of persistent micropollutants in water.

DOI： 10.3390/jcs4020054

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DOI： 10.1016/j.ecss.2019.106580

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.watres.2020.115643

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Society of Civil Engineers (ASCE)  

DOI： 10.1061/(asce)ir.1943-4774.0001439

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DOI： 10.1002/hyp.13525

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/hyp.13525

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DOI： 10.1126/sciadv.aav0486

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DOI： 10.1016/j.chemosphere.2017.04.008

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DOI： 10.1371/journal.pone.0176484

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DOI： 10.1016/j.scitotenv.2016.10.068

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DOI： 10.2208/jscejhe.73.I_1201

CiNii Books

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DOI： 10.1016/j.watres.2016.07.033

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食物連鎖の根底を担う藻類を含め生物にとって不可欠な微量元素である鉄は, 陸域から河川や地下水を経て下流に移行し, 沿岸域での基礎生産に貢献していると考えられている。本総説では, このような流域における鉄の生物地球化学動態について既往研究を整理した。鉄の化学的特性として, 中性pHでは無機第二鉄の溶解度はサブナノモーラーであること, 溶存有機物が鉄の溶解度を上昇させること, 種々の熱力学・光化学的反応が鉄の生物利用性と密接に関係することが明らかにされている。また, 微細藻類による鉄の生物利用性は鉄の化学種に強く依存するため, 陸域由来鉄が沿岸域の基礎生産に及ぼす影響を適切に評価するには, 鉄の化学種に着目して研究を進めていく必要がある。森・川・海のつながりにおける鉄と有機物の動態研究では, 陸での有機鉄の溶出から沿岸域生態系への移行までをカバーした総合的な研究が重要と考えられる。

DOI： 10.2965/jswe.39.197

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DOI： 10.1007/s10201-015-0458-3

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DOI： 10.2208/jscejer.71.III_287

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DOI： 10.14862/geochemproc.62.0_263

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DOI： 10.1021/es405496b

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

The oxidation kinetics of ferrous iron (Fe(II)) in the presence of humic substances, which widely occur in natural water, was investigated by determining the oxidation rate constants of Fe(II) by dissolved oxygen (O₂) and hydrogen peroxide(H₂O₂) (k_O2 and k_H2O2, respectively) in a bicarbonate buffer at pH 8. The Fe(II) oxidation experiments indicated that both k_O2 and k_H2O2 varied widely depending on the type of the co-existing humic substance, while the oxidation rate constant for O₂ was found to be greater in the presence of humic substance. The oxidation rate constant for H₂O₂ significantly correlated with the contents of carboxyl group and aromatic carbon in humic substance. The finding from our study indicates that the oxidation rate of Fe(II) is likely altered by the complexation of Fe(II) with humic substances with the rate dependent on the types and quantities of Fe-binding sites in humic substance in addition to the charge characteristics of coordinating ligand.

DOI： 10.2208/jscejer.69.iii_291

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

In this study, we investigated i) relationship between habitat type and qualitative and quantitative characteristics of deposited sediment and (ii) the characteristics of deposited sediment and respiration activity of the sediment as determined by oxygen consumption rate in a floodplain of the Tagliamento River. Field observation indicated that C/N ratio and size of sediment increased in upstream-connected backwater and main stream, while habitats with high abundance of trees provided high density of fine particulate sediment (FPS) as well as high content of fine particulate organic matter (FPOM). We confirmed that the FPS density and FPOM content have strong correlation with dissolved oxygen consumption rate, suggesting that the oxygen consumption rate in water column is influenced by habitat type and quality and quantity of sediments.

DOI： 10.2208/jscejer.68.III_205

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

It is important to understand complexation between humic substances and iron in view of the assessment of iron bioavailability in natural water environment. In this study, iron complexation by humic substances from a variety of origins were investigated by measuring stability constant and complexation capacity using the competitive ligand method. In addition, relationship between such complexation parameters and chemical properties of humic substances was examined. Statistically significant positive correlation between the complexation capacity and amount of aromatic carbons of humic substances (as determined by ¹³C-NMR) was provided. Therefore, functional groups resident in aromatic region are likely responsible for iron coordination. In addition, stability constant has significant correlation with sulfer and nitrogen content of humics (as determined by elemental analysis), suggesting that sulfonic and amino groups bind to iron with higher stability constant.

DOI： 10.2208/jscejer.68.III_525

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DOI： 10.1021/jp202440e

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DOI： 10.1007/s10533-010-9412-y

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  The initial effect of dam impoundment on particulate organic matter (POM) dynamics in streams was studied in the forested region of the Ibi River basin, including a newly constructed dam (Tokuyama Dam). In the intact sites, POM fractions larger than 1μm mostly consisted of allochthonous POM and only the largest fraction (> 2mm) reflected the seasonality of litter fall in its concentration. In the downstream section of the dam, only large fraction (> 2mm) showed a sharp decrease in concentration. For POM from 63μm to 2mm, nearly 50% of reservoir-derived POM was exchanged in 3km downstream section. Thus, the downstream POM dynamics probably reflected the low primary production in the reservoir.

DOI： 10.2208/jscejg.65.237

J-GLOBAL

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This study focused on the relationship between land use and coliphage concentration in rivers in Gifu city. We sampled river water at 20 sites along four urban rivers and analyzed water chemistry and concentrations of F-RNA and somatic phages and Escherichia coli. Coliphage concentrations were the highest along agricultural land followed by urban area and forest. River section receiving treated sewage water showed lower coliphage concentration than that without treated sewage water in urban area. This study revealed that pathogenic virus concentration is higher in suburb, agricultural and residential areas, than in the city center, which implied diffuse pollution of pathogenic virus in water environment.

DOI： 10.11532/proes1992.45.379

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Language：Japanese   Publisher：日本陸水学会  

DOI： 10.14903/jslim.71.0.28.0

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DOI： 10.2208/jscejg.62.74

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Language：Japanese   Publisher：Japan Society on Water Environment  

Switzerland is the primary "watershed of Europe." The Swiss Alps feeds all major Central European rivers including the Rhône, Danube, Rhine and Po. The country also plays a very active international role in environmental affairs since many multinational organizations such as the United Nations, the International Union for Conservation of Nature and Natural Resources (IUCN) and the Ramsar Convention are based in Switzerland. In the present paper we give a brief overview of the water policy of Switzerland and provide selected examples of the state and trends of the water environment. The most fundamental principles in water management were formulated in the Water Protection Law in 1991 and subsequently updated in 1991. In it, the protection of groundwater and the maintenance of residual flow in rivers and streams were manifested. Ground water supplies 80 % of the total water consumption of the human population. Local authorities identify groundwater protection areas, and unpolluted wastewater such as storm water is also used to recharge the aquifer. Furthermore, minimum residual flows are calculated to maintain the ecological integrity of rivers and streams. Finally, we compare the Swiss situation with the water conservation policy in Japan.

DOI： 10.2965/jswe.26.93

CiNii Books

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Other Link： https://jlc.jst.go.jp/DN/JALC/00163980607?from=CiNii

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Civil Engineers  

Experiments on the leaching of DOM from riverine POM fractions were conducted to investigate the qualitative and quantitative formation of dissolved organic matter (DOM). Amphipods (Gammarus sp.) were fed in the laboratory with preconditioned leaves of Fraxinus excelsior, Alnusincana, and Querrus robur, twigs of Populus nigra, and epilithic algae (periphyton). Amphipods produced two FPOM fractions (L-FPOM: 250-500μm; M-FPOM; 100-250μm). L-FPOM consisted primarily of fecal pellets while M-FPOM was mainly composed of CPOM fragments created by the feeding activity. FPOM fractions and CPOM were exposed in 100ml Erlenmeyer bottles and stirred at 100rpm at 12°C under dark conditions. DOC release rate, UV absorption (E285) and microbial respiration (Biological Oxygen Demand in 3 days) were repeatedly measured over a 14-day period.<BR>FPOM exhibited significantly lower DOC release rate than CPOM in first 24 hours of the experiment while it was slightly higherthan CPOM in the second week. DOM release rate from air-dried leaves (CPOM) was significantly correlated with chlorophyll acontent. Microbial respiration suggested that POM was converted by bacterial community into more refractory compound whilereleasing relatively labile DOM. In addition, POM derived from epilithic algae showed distinct leaching mechanism from allochthonous POM.

DOI： 10.11532/proes1992.40.139

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.11532/proes1992.35.415

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DOI： 10.3825/ece.9.85

Scopus

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Event date： 2024.6

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Language：English   Presentation type：Poster presentation  

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Language：Japanese   Presentation type：Oral presentation (general)  

researchmap

Language：English   Presentation type：Oral presentation (general)  

Venue：Semarang   Country：Indonesia  

researchmap

Language：English   Presentation type：Oral presentation (general)  

Venue：Semarang   Country：Indonesia  

researchmap