A5009468903- Microplastics and Plastic Pollution
- Climate change and permafrost
- Peatlands and Wetlands Ecology
- Water Resources and Management
- Soil and Water Nutrient Dynamics
- Soil Carbon and Nitrogen Dynamics
- Recycling and Waste Management Techniques
- Agriculture, Soil, Plant Science
- Geological Studies and Exploration
- Aquatic and Environmental Studies
- Coastal wetland ecosystem dynamics
- Heavy metals in environment
- Soil and Environmental Studies
- Marine and coastal ecosystems
- Cryospheric studies and observations
- biodegradable polymer synthesis and properties
- Soil and Land Suitability Analysis
- Ecology and biodiversity studies
- Fire effects on ecosystems
- Urban and spatial planning
- Mine drainage and remediation techniques
- Indigenous Studies and Ecology
- Coal and Its By-products
- Geochemistry and Geologic Mapping
- Electrostatics and Colloid Interactions
Tokyo Metropolitan University
2015-2024
National University of Mongolia
2024
Japan Atomic Energy Agency
2024
Science Council of Japan
2022
Nihon University
1998-2012
Martin Luther University Halle-Wittenberg
2004
Kobe University
1995-2001
Graduate School USA
1995-1996
The pivotal role of soil as a resource is not fully appreciated by the general public. Improving education in science represents challenge world where resources are under serious threat. Today's high school students, world's future landowners, agriculturalists, and decision makers, have potential to change society's apathy towards soils issues. This research aimed compare level and/or secondary schools forty-three countries worldwide, together comprising 62% population. Comparisons were made...
Abstract The Yenisei river passes every type of permafrost regime, from south to north, being characterized by increasing continuity the and decreasing thickness active layer. We used that situation test hypothesis amounts properties dissolved organic matter (DOM) in small streams draining forested catchments respond different regimes. Water samples were taken eight tributaries along between 67°30′N 65°49′N latitude. analysed for carbon (DOC) nitrogen (DON) DOM was its chemical composition...
Abstract Because of low net production in arctic and subarctic surface water, dissolved organic matter (DOM) discharged from terrestrial settings plays an important role for carbon nitrogen dynamics aquatic systems. Sorption, typically controlling the export DOM soil, may be influenced by permafrost regime. To confirm potential sorptive control on release soils central northern Siberia, we examined sorption mineral Gelisols Inceptisols with varying depth active layer. Water‐soluble O...
Urban soils have been drastically disturbed and modified by human activities. Soil sealing, necessary for transportation infrastructure development, is one such process, which often results in negative effects on the soil ecosystem functions. However, sealed can play a critical role material cycling through ground surfaces urban ecosystems. This study investigated of asphalt sealing mineral beneath roads Tokyo. The confirmed that pavements were characterized high pH levels, CaO content,...
Abstract Elemental composition and solution 13C NMR spectra for six humic acid fractions with different particle sizes (i.e. 3K, 10K, 30K, l00K, 300K, 500K) which were prepared from a in an Umbric Andosol by successive gel permeation chromatography determined. of the size clearly differed one another. Contents nitrogen hydrogen increased increase size. Small middle (3K to l00K) showed low contents corresponding those typical acids, while large (300K distributed ranges other acids. As...
Abstract Water-soluble ionic substances in acid sulfate soils are likely to be strong controls for crop production and have impacts on aquatic ecosystems. In dry seasons, particular, oxidation of the soil surface followed by acidification probably produces lots acids soluble metals. To estimate metal loads from environments, we determined composition water-soluble ions distributed Mekong Delta, Vietnam. At end season, were taken each horizon two profiles delta under different land...
Plastic pollution in river environments has become an emerging global concern. However, the migration of plastic and changes its properties between compartments are less understood. This study demonstrates debris aging dynamics floodplain, surface water, sediment Tuul River, Mongolia. occurrence is evaluated terms their abundance, size, shape, polymer type, photodegradation each compartment. Photodegradation stages were calculated using carbonyl index (CI). abundance was 5.46 ± 3.53 items m
Abstract Humic acids (HAs) extracted from an Umbric Andosol (UA) and a Dystric Cambisol (DC) were fractionated into 7 fractions by successive gel permeation chrontatography (GPC) their studied spectral analysis. With increasing particle sizes, the absorption of methylene groups amide peptides increased in IE spectra both HAs that carboxylic decreased IR UA, HA obtained Andosol. Based on 1? NMR data there was significantly negative linear correlation (−0.950, p< 0.001) between Har (δ 6.0-9.0...
Abstract Humic (HAs) and fulvic acids (F As) were obtained from A horizons of four different soils (a Fibric Histosol, Dystric Cambisol, Umbric Andosol, buried Andosol) by the sequential extraction with pyrophosphate solutions at pHs (i.e. pH 3, 5, 7, 9, 11, 13). The yield FAs decreased increase in values 3 to then, increased or remained constant 9 13. distribution pattern HAs differed among soils, total for extracted extending acid neutral region (3–7) was equal higher than that alkaline...
Abstract Acids and soluble metal loads resulting from strong acidification preceded by severe drying of acid sulfate soils are fatal soil conditions for agricultural productivity aquaculture environments. A greater concentration dissolved Al Fe after seasonal drought was confirmed in our previous paper using the Mekong Delta. Furthermore, moisture desiccation land-use change subsoil excavation drainage probably promotes oxidation followed acidification. We prepared air-dried condition actual...
The effects of different land-use histories on contents soil carbon (C) and nitrogen (N) fluxes greenhouse gases [carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O)] measured using the closed chamber method were investigated in Arkaim museum reserve located South Ural Russia. A natural forest site (NF) two grassland sites that had (CL: cropland until 1991; PST: pasture both have been fallow for 18 years) selected sampling gas flux measurements. vegetation NF was mainly Betula pendula...
Abstract The relationships between surface active properties and humic acid (HA) particle sizes were investigated. Two HAs from an Ando soil a Brown forest separated into 6 size fractions by gel permeation chromatography. Surface-active characterized excess value (\gT mol cm-2), cross-sectional area per molecule (A nm2), critical micelle concentration (CMC g L-1), efficiency effectiveness of water tension reduction obtained the measurement HA solutions different fractions. For soil, except...