A5010035693- Soil Carbon and Nitrogen Dynamics
- Biological Control of Invasive Species
- Agriculture, Soil, Plant Science
- Rice Cultivation and Yield Improvement
- Cassava research and cyanide
- Urban and Rural Development Challenges
- Constructed Wetlands for Wastewater Treatment
- Peatlands and Wetlands Ecology
- Agronomic Practices and Intercropping Systems
- Rural development and sustainability
- Land Rights and Reforms
- Groundwater and Isotope Geochemistry
- Soil and Unsaturated Flow
- Soil and Water Nutrient Dynamics
- Agricultural Science and Fertilization
- Local Economic Development and Planning
- Weed Control and Herbicide Applications
- GABA and Rice Research
- Isotope Analysis in Ecology
- Plant nutrient uptake and metabolism
- Urbanization and City Planning
- Bioenergy crop production and management
- Wastewater Treatment and Reuse
- Anaerobic Digestion and Biogas Production
- African history and culture studies
Iwate University
2019-2025
National Institute for Agro-Environmental Sciences
2023-2025
Japan Society for the Promotion of Science
2023-2025
Yamagata University
2016-2022
University of Nairobi
1972
Azolla (Azolla filiculoides) is a common aquatic fern that has been used successfully as dual crop with lowland rice. It grows rapidly and the ability to fix N2 for rice paddy. However, its ecological significance especially on greenhouse gases emissions remains unclear. To investigate effect of azolla cover methane (CH4) nitrous oxide (N2O) from paddy, pot experiment two treatments, control (rice plant only) plus covering flooding water), was carried out in Tsuruoka, Yamagata, Japan, 2016....
Hot-water- and water-extractable organic matter were obtained from soil samples collected a rice paddy 31 years after the start of long-term experiment in Yamagata, Japan. Specifically, hot-water-extractable carbon nitrogen (HWEOC HWEON) by extraction at 80°C for 16 h, (WEOC WEON) room temperature. The surface (0–15 cm) subsurface (15–25 layers five plots that had been treated with inorganic fertilizers alone or plus matter, as follows: PK, NPK, NPK straw (RS), compost (CM1), high dose...
Poultry-litter biochar and Azolla as green manure amendments are reported to enhance paddy soil fertility rice yields. However, whether their co-application in lowland paddies has synergistic effects those benefits accompanied by greenhouse gas (GHG) emissions remains unknown. The objective of this study was determine the poultry-litter (hereafter: biochar) its with Azolla), on simultaneous methane (CH4) nitrous oxide (N2O) from a planted during single growing season Tsuruoka, Yamagata,...
To determine methane (CH4) emission differences between edible and forage rice cultivars, we conducted a pot experiment in Yamagata, Japan to grow Haenuki, Fukuhibiki (for feed rice) Tachisuzuka whole-crop silage (WCS) under similar soil meteorological conditions. The total amounts of N, P, K fertilizers applied for were 1.7, 1.3, 1.3 times, respectively, higher than those Haenuki. CH4 fluxes, plant night respirations measured once weekly or fortnightly. As per the results, whole growth...
Different weeding frequencies (WFs)―0WF, 2WF, 4WF, 6WF, and 8WF―were adopted in an organic rice field to investigate their influence on weed types, biomass, tiller number, N concentration, uptake. The study was located Tsuruoka, Yamagata, Japan. Rice (cv. Sasanishiki) planted from May September 2019, all events were carried out until 49 days after transplantation (DAT) using a rotary weeder. samples collected at 60, 88, 110 DAT. Echinochloa crus-galli (E. crus-galli), Schoenoplectus...
Global warming can accelerate soil organic matter (SOM) decomposition resulting in faster carbon loss and positive climate-C feedback. Previous studies on response of SOM to climate change mainly focus plow layer. However, the effects elevated CO2 (SOC) total nitrogen (TN) contents mineralization are rarely studied subsoil In this study, samples were collected from 0–50-cm paddy layer Tsukuba free-air enrichment experimental site with (+200 ppm) (+2 °C), Japan, after 5-year rice growth...
To investigate the influence of Azolla (A. filiculoides Lam.) incorporated as a green manure and its subsequent growth dual crop with rice on simultaneous methane (CH4) nitrous oxide (N2O) emissions from flooded alluvial soil planted rice, pot experiment three treatments, chemical fertilizers (NPK) control, incorporation (AGM), AGM plus basal (NPK+AGM) was conducted in Tsuruoka, Yamagata, Japan 2017. NPK+AGM treatments significantly increased CH4 at early stages before 63 days after...
Foxtail (Alopecurus aequalis) and milk vetch (Astragalus sinicus) are typical winter weeds grown in single-cropping rice fields during the fallow season central Japan. These generally incorporated into soil as green manure plowing, before transplanting, to improve fertility yield. To understand carbon (C) decomposition nitrogen (N) mineralization behavior of organic farming, we carried out two experiments. Firstly, examined effect adding 1% foxtail soils that were sampled from farmed...
Interests in studies of the status land are varied. The tenure systems, allocation and functional utilization, value, disposition size, quality pattern parcels, but a few range topics appearing literature on to which many disciplines have contributed. Numerous been made systems rural areas, structure ownership urban areas has largely ignored.1 Thus, primary purpose this paper is examine Nairobi.2 Various important questions investigated. For example, who owns what ? What acreages values...
Our previous pot experiments showed that using Azolla either or both as dual and green manure with rice increases its yield significantly reduces methane (CH4) nitrous oxide (N2O) emissions. To confirm these findings in an actual field, was grown a crop (herein Cover) incorporated plus cropping AGM + at the beginning of experiment along rice. Compared control (chemical fertilizer; herein NPK), NPK Cover treatments did not influence cumulative CH4 emissions throughout growth period. However,...
Significantly, soil fertility and rice variety influence growth. Under different conditions, Indica "Takanari (Tak)" outperformed Japonica "Koshihikari (Kos)" in terms of N-uptake biomass production. However, it is still unclear how Tak Kos respond to growth low-fertility (sandy) normal (alluvial) soils. Therefore, we conducted a pot experiment at Tsuruoka the 2022 rice-growing season. were transplanted individually interplanted (Tak+Kos) with main treatments alluvial soil, sandy, sand...
<span style="color: windowtext; line-height: 200%; font-family: 'Times New Roman','serif'; font-size: 12pt; mso-fareast-font-family: 'ＭＳ 明朝'; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA;" lang="EN-US">Hot water- and water-extracted organic matter was extracted from soil samples collected after a 31-year long-term experiment which aimed to assess the effect of different fertilization strategies (inorganic fertilizers matters) commonly used for paddy...
This study investigated the effect of land-use and management change (LUMC) on carbon (C) nitrogen (N) dynamics after 15–40 years. LUMC constituted from rice paddies to chestnut orchard, wetland, buckwheat upland fields in Shonai region, Yamagata Prefecture, Northeast Japan. Soil samples were collected top – (0–15 cm) sub-layers (15–30 for analysis soil organic C (SOC) its δ13C value, total N (TN), their stocks. decomposition (Dec-C) net mineralization (Net Min-N) determined according...
To determine the difference in greenhouse gas emissions between two rice (Oryza sativa L.) varieties; Takanari (Tak) and Koshihikari (Kos), under organic cultivation with or without weeds management, a pot experiment was conducted at Tsuruoka, Yamagata, Japan. The Tak Kos varieties were transplanted individually interplanted as Tak+Kos, main treatments of weeding (w) no-weeding (nw). Methane (CH4), nitrous oxide (N2O), plant night respiration (CO2 emission) fluxes measured once weekly...