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The importance of soil management has been recognized internationally. In Japan, the interest in soil management has recently been increasing as the compost input into agricultural land has been decreasing. Owing to recent increases in chemical fertilizer prices, increased production costs in agriculture have become a challenge. Furthermore, the current strategy of the Japanese and European Commission for Sustainable Food Systems is to reduce the use of chemical fertilizers. From this perspective, there are considerable expectations for soil management and fertilizer reduction using organic matter. This review focuses on cover crops for soil management and for green manuring, an organic material that is advantageous in terms of transportation costs and the application of labor. First, the results of scientific research on the function of cover crops in improving the soil environment in the surface layer (organic matter accumulation, erosion control, and improvement of soil biological properties) and in the subsurface soil layer (physical properties) are reviewed. Next, the mechanisms of cover crops in supplying nutrients (nitrogen, potassium, and phosphorus) to cash crops as green manure are reviewed. Finally, I reviewed the ways in which the benefit of cover crops can be enhanced (species selection, growth stage of incorporation, and methods and timings of seeding the following crops). Because the effects of the introduction of cover crops on soil quality and cash crop production have been indicated quantitatively, the use of cover crops is expected to expand and contribute to reducing chemical fertilizer use and improving soil quality in the future. [ABSTRACT FROM AUTHOR]

Butterflies are declining globally, mainly due to expansion and abandonment of agricultural land. Quantifying the relative importance of agricultural land-use types for butterflies is essential to conservation planning in agricultural landscapes, where land-use changes frequently occur. Here, we surveyed species richness, abundance, and composition in natural lands (wetland and forest), agricultural land, and abandoned agricultural land in two topographic settings (hillslope and lowland) in Hokkaido, northern Japan. The species richness and abundance of open-land butterflies tended to be the highest in agricultural lands in both topographic settings. Although those of communities were lowest in natural lands, such areas had unique species compositions. Topography can be an important factor explaining the variation in species richness and abundance among abandoned agricultural lands. In hillslope areas, abundance of open-land butterflies was lower in abandoned agricultural lands than in active ones. In lowland areas, however, species richness and abundance of abandoned agricultural lands were comparable to those of active ones in both communities and functional groups. Our results suggest that both topography and land-use type have significant effects on butterfly community composition in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Japan's susceptibility to and severity of floods have necessitated flood control policies by the government. "Overflowing flood control", in which the floods due to torrential rains are systematically diverted to agricultural lands in the upper to middle reaches, is one of them. More information is needed on the public assessment of the overflowing flood control policy, and this research seeks to bridge this gap. Data evaluating rice affected by the policy were collected from a random nth-price auction using a developed online system. The sample consisted of 47 consumers living in the downstream areas of the Edogawa River, one of Japan's first-class, or prime, rivers. Data on their attitudes toward the policy were collected with a questionnaire. Multiple ordered probit models are used for regression analysis. The results show that the sample respondents were willing to pay an average of JPY 1578 for 5 kg of rice, slightly higher than the national average rice production cost, and that 36% of the sample agreed with the flood control policy, which is positively associated with large families or owning many assets. [ABSTRACT FROM AUTHOR]

Decarbonization and idle cropland reclaiming pose critical policy challenges. Agrivoltaic systems (AVSs), which merge agriculture and photovoltaics, offer a promising solution by reducing land use conflicts between agriculture and energy production. This study develops a GIS-based methodology to identify reclaimable idle croplands and assess the AVS's contribution to agriculture and photovoltaic energy in Japan's Kansai region. Using official geographic data and excluding high-risk areas, this study employs GIS for quantitative analysis. Our method detected more reclaimable idle cropland than previous studies. Focusing on food security while limiting AVS installations to reclaimable idle croplands could still generate up to 4564.08 GWh of electricity (0.8% of regional consumption) and 930.82 tons of soybeans (6.2% of regional yield). Under a more stringent scenario that excludes areas less suitable for solar power, 5 of 227 municipalities could achieve 15% electricity self-sufficiency through AVS. This research uncovers the existence of reclaimable idle croplands that could not be detected by existing methods and a decentralized power source available alongside food security maintenance. These insights will inform decarbonization and agricultural policy and guide the development of supportive and regulatory AVS frameworks. [ABSTRACT FROM AUTHOR]

Rice terraces are a time-honored agricultural feature that overcomes rough terrain and hostile growing conditions. In addition to playing an essential role in agricultural production and land conservation, rice terraces have been recognized as living cultural landscapes, important agricultural heritage, and popular agritourism destinations for their aesthetic, sociocultural, and environmental values. However, there is a lack of understanding of this emerging niche market, especially from outsider perspectives. To fill the gap, this study analyzes Google Maps reviews of seventy representative rice terraces in Japan based on a mixed-method content analysis, aiming to identify visitors' overall experiences, seasonal perceptions, and the causes of negative experiences. The results indicate that the overall experience of rice terraces in Japan includes seven themes: agricultural landscapes, times and seasons, visual perception, accessibility and infrastructure, sense of place, Genfukei of Japan, and food. Visitors' perceptions toward the four seasons of the rice terraces have distinctive characteristics and result in different satisfaction levels. The main reasons for negative experiences are farmland abandonment, lack of character, poor accessibility, and bad timing. Leveraging the power of netnography, the study sheds light on the sustainable development of agricultural heritage tourism through the introduction of rice terrace conservation initiatives in Japan and the exploration of rice terrace experience. [ABSTRACT FROM AUTHOR]

How do you explain centralized farm mobilization in Japan and decentralized farm mobilization in Korea in response to agricultural liberalization pressures? The divergence is puzzling given strong similarities in Japan and Korea's agricultural sectors and institutions. Electoral competition that accentuates the urban–rural divide in society works in favor of centralized farm political mobilization, whereas electoral competition that minimizes the urban–rural divide works in favor of decentralized farm political mobilization. The logic is that when electoral competition cuts across the urban–rural cleavage, farmers face greater challenges in mobilizing under a centralized farm group for electoral purposes. Simply put, farmers are unable to act as a unified voting bloc. Relatedly, political parties also face less electoral incentives to specifically target farmers as a unified voting bloc. [ABSTRACT FROM AUTHOR]

There has been broad recognition that current food systems need to go through a process of transformation and transition. In the similar way that other areas have transitioned to be more sustainable, the transition process for food systems has some issues related to justice in terms of achieving more sustainable and inclusive food production, distribution and consumption. Acknowledging the importance of these issues, this article aims to understand how knowledge about desired changes is produced and shared among people engaged in activities to transform food production and consumption. To this end, it analyses the short narratives of urban citizens in Japan engaged in participatory farming, adopting the concepts focusing on the contrasts embedded in the short stories, learning from risk studies. The farmer, volunteer staff members and urban citizens collaborate to grow rice using traditional techniques. Their narratives reveal some contrasts in how they used to engage with food, farms and the local environment, and their engagement now. Furthermore, it was observed that these citizens reconfirm the importance of knowledge learned through actual work on the farm and the different roles played by the farmer, volunteers and local participants in creating and passing on knowledge. In such ways, people's interaction leads to the creation of shared meanings of "appropriateness" in terms of existing and emerging food-related practices. This matter of meaning-making for "appropriateness" is often overlooked in the discussion of the justice in food systems' transitions. [ABSTRACT FROM AUTHOR]

Soil properties have been known to be the factors that influence the ionization process in soil, which cause the impulse impedance, Zimpulse to be lower than that at steady state resistance, RDC. Many studies have established the relationship between the percentage reduction of Zimpulse from RDC in such that the percentage reduction is more pronounced in high resistivity soil, or in high RDC, than that at low resistivity soils. Nevertheless, Zimpulse is not the only parameter in representing the characteristics of soil under high impulse conditions, where from the voltage and current waveforms, the current rise and discharged times can also be established, where more accurate and extensive analysis of the electrical characteristics of ground electrodes subjected to high impulse currents can be achieved. This paper presents the experimental results of four ground electrodes, installed in agricultural land, with soil resistivity, of below 3 Ωm, subjected to high impulse currents, where the parameters of current rise times, Zimpulse and current discharged times were investigated. Two of these ground electrodes are having close RDC values, despite having different electrode's configurations, were also investigated. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate people's preferences for the geographical distance between residential locales and two types of urban agricultural land, namely, traditional agricultural land and a more complex and intensive agricultural landscape called "satoyama" and to evaluate the heterogeneity in people's preferences. The enhancement of urban sustainability is a crucial issue in sustainable development that can be potentially improved by urban agriculture. However, urban residents' perceptions and preferences regarding the distance between urban agricultural land and their locales remain unclear, and concrete measures to maintain and expand urban agriculture are still vague. Therefore, an online survey and choice experiment was conducted, with respondents from Ishikawa Prefecture in Japan, who are assumed to be familiar with the agricultural context. Mixed logit and latent class logit models were employed to evaluate urban residents' heterogeneous perceptions and preferences. The results reveal that: (1) urban residents generally prefer urban agricultural land in areas away from their residence; (2) preferences are diverse, and those who are relatively young, with higher income, and more environmentally conscious favor dwelling near urban agricultural land; (3) there is a quadratic relationship between the distance connecting people's locales and urban agricultural land, and thus, the most desirable distance exists; and (4) there is a difference in the proximity that people prefer between traditional agricultural land and satoyama. Based on the results, policy implications for urban planners and policymakers include implementing urban agriculture in peri-urban areas and handling a tradeoff between residential opposition and the intensity of urban agriculture. [ABSTRACT FROM AUTHOR]

Benefiting from rich agricultural land, easy transport and fishing, etc., more and more people are moving to live in coastal areas, with more than 200 million people now living in coastal areas that are vulnerable to extreme sea level events. Sea level information is useful for coastal societies. Image measurement is rapidly developing as a new type of measurement tool. A multicamera-based sea level monitoring system along Japan's coast near the Pacific is proposed in this paper, and a long-distance sea wave matching method for this system is described. The whole system employs multiple binocular vision systems to take sea surface images and obtain the sea level height based on the disparity between the field of views of the left and right cameras, forming a local measurement and overall analysis monitoring system. Sea level monitoring requires a high processing accuracy and speed to realize a timely response to extreme events. Thus, the paper extracts sea waves and integrates a sea wave's appearance features as feature points and descriptors and pioneers the idea of searching deterministic features for fast image processing. The average stereo matching precision of the proposed method is up to 89.9% with a running time smaller than 40 ms for most pairs of images. Experiments on various real sea surface image pairs are conducted to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

During the 2023-2024 winter, 11 high pathogenicity avian influenza (HPAI) outbreaks caused by clade 2.3.4.4b H5N1 and H5N6 HPAI viruses were confirmed in Japanese domestic poultry among 10 prefectures ( n = 10 and 1, respectively). In this study, we aimed to genetically and pathologically characterize these viruses. Phylogenetic analysis revealed that H5N1 viruses were classified into the G2d-0 genotype, whereas the H5N6 virus was a novel genotype in Japan, designated as G2c-12. The G2c-12 virus shared PB2, PB1, PA, HA, and M genes with previous G2c viruses, but had NP and NS genes originating from avian influenza viruses in wild birds abroad. The N6 NA gene was derived from an H5N6 HPAI virus that was different from the viruses responsible for the outbreaks in Japan in 2016-2017 and 2017-2018. Experimental infections in chickens infected with H5N1(G2d-0) and H5N6(G2c-12) HPAI viruses showed no significant differences in the 50% chicken lethal dose, mean death time, or virus shedding from the trachea and cloaca, or in the histopathological findings. Different genotypes of the viruses worldwide, their introduction into the country, and their stable lethality in chickens may have triggered the four consecutive seasons of HPAI outbreaks in Japan.

This study aimed to examine the issues and development directions concerning farm stays led by residents in Saikai City of Nagasaki Prefecture, Japan. The main outcomes were as follows: first, the financial situation of the secretariat was severe, and adminislxative support was indispensable. Second, due to the influence of COVID-19, the income from educational trips decreased sharply in comparison to that from tourism. Third, to maintain the secretariat, it was deemed necessary to attract tourists. The development directions involved creating full-time farm stays and promoting them under the regional management organization. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated the importance of the bioavailability of particulate phosphorus (PP) exported from various watersheds, especially agricultural land. However, few studies have documented the influence of hydrological conditions on the sources and bioavailability of PP exported from watersheds with multiple land uses. In this study, to assess the sources and bioavailability of PP under different hydrological conditions, we conducted synoptic monitoring of compositional changes in the chemical fractions of PP exported from the Yasu River Watershed, which is covered with a mixture of forest (57.7%) and rice paddy (20.5%) areas. In this river, total phosphorus was composed mainly of PP at all monitoring sites and time points. The sequential extraction of PP revealed that a fraction bound to redox‐sensitive iron and manganese, regarded as bioavailable, was specific to the drainage waters of rice paddies, while a fraction bound to organic matter, regarded as less bioavailable, was specific to a forested stream. In the downstream of the Yasu River covering the whole watershed, PP exported under the base flow and small rainfall conditions was composed mainly of the rice paddy‐derived fraction, while most of the PP exported under heavy rainfall conditions was the forest‐derived fraction. These results suggest that the sources and bioavailability of PP can vary dynamically, depending on the hydrological regimes and land use pattern in the watershed. Even taking into account the fact that the large amount of PP exported during heavy rainfall is considered to be forest‐derived PP with low bioavailability, the monitoring results suggested that the annual amount of bioavailable PP exported is larger than that of dissolved phosphorus, and can have a large impact on phosphorus recycling in the downstream lake ecosystem through sedimentation and regeneration. [ABSTRACT FROM AUTHOR]

Despite rapid population aging and depopulation in Japan, groundwater nitrate contamination still poses serious environmental problems. One of the main factors contributing to elevated nitrate levels in Japanese groundwater sources is agricultural intensification, frequently because of increased fertilizer use. We investigated the impact of population aging and depopulation on groundwater nitrate contamination on a western Japanese island that has extensive citrus farming. In comparison to Ocho village, where the average age of farmers is 73 years, Kubi village's farmers are slightly older on average, at 76 years, and agricultural land has decreased by 46% over the past ten years, from 2005 to 2015. Ocho had 830 residents, which was twice as many as Kubi. In comparison to Ocho (4.8 mg/L), Kubi village had higher average NO3−−N concentrations (6.6 mg/L). NO3−−N contamination sources in Kubi and Ocho were determined using stable nitrogen isotopes and a Bayesian isotope mixing model. These source distributions were more strongly associated with social and land use factors. It was believed that the older farmers in Kubi employed a significant quantity of chemical fertilizers, which caused inefficient nitrogen uptake by plants, leading to increased leaching and more groundwater contamination than in Ocho. [ABSTRACT FROM AUTHOR]

Policies in Japan are shifting focus on sustainable land-use management-related policies through consensus building, given the complex options for the community and the landowners. For instance, conversion of agricultural lands to renewable energy sites, which is an example of "land-use conversion for a newly found objective", is rapidly progressing, and actions on "managing of croplands in a minimal (low labor demand) way" has been embodied in certain policies. Currently, there are political and scientific efforts to balance environmental conservation with production activities in agriculture and forestry sectors based on science and evidence. With policies catching up, it is possible to confirm what has been moved from the planning to the implementation stage of the proposed consensus-building system by summarizing and discussing the current progress of the project. More specifically, we highlighted the trends in reusing agricultural lands under the current national-level policies and management options for croplands, such as the "less maintenance way." We also discussed and presented the preliminary results, insights, and prospects from the ongoing project, which then led to the discussion of future considerations in sustainable land-use management in Japan. [ABSTRACT FROM AUTHOR]

In order to increase productivity in national agricultural land and help depopulated villages with aging farmers, current agricultural policy in Japan rewards small farmers who contribute their land to agriculture corporations in which they own shares, have a vote, and labor in the fields for a low wage. Membership is individual, and the sacred link between household and land is virtually cut. Akata, a small village in northeast Japan, has formed agriculture corporations that result in tensions, new alignments, and marginalizations that are well captured by Foucault's concept of heterotopia: a displacement and regrowth that juxtapose villagers' pasts, presents, and futures in disruptive yet creative ways. An anthropological analysis unearths social nuances bridging new roles and older connections. [ABSTRACT FROM AUTHOR]

Using D2 gas as a substrate, this study investigated the hydrogen deposition velocities of farmland soils around a reprocessing plant located in Rokkasho Village, Aomori, Japan. To determine the hydrogen deposition velocities, closed chambers with fans were set on the soils of farmlands that grow Japanese radishes, and changes in D2 concentration in the chambers were measured by gas chromatography. Results showed hydrogen deposition velocities of six soils were within the range of 1.0 × 10-4 ~ 2.0 × 10-4 m s-1. The heavy water (HDO) formations were detected in the soil after the experiment, showing the oxidation of D2 and conversion to water. Relationships between the obtained hydrogen deposition velocities and environmental conditions such as soil temperature, moisture and porosity were examined. A correlation was found between the hydrogen deposition velocities and soil gas phase rate (r = 0.98, p < 0.05)., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Infectious diseases in livestock not only cause significant economic losses but also affect food security. Although wildlife may be involved in these infectious diseases by serving as reservoirs, research has primarily focused on livestock and related species. Moreover, while these species represent a potential threat in wildlife-borne infectious diseases, comprehensive surveys of the presence of various species are limited. In this study, we aimed to quantitatively investigate the occurrence of various mammals and birds at three pig farms in Japan. We conducted camera trap surveys from October 15, 2020, to March 24, 2022, and determined the relative abundance index inside and outside the sanitary control zone. Wild boar (Sus scrofa), sika deer (Cervus nippon), and Japanese serow (Capricornis crispus) were photographed only outside the sanitary control zone. In contrast, small and medium-sized mammals, such as feral cats (Felis catus), raccoons (Procyon lotor), and rodent species (Muridae), and birds, such as the rufous oriental turtle dove (Streptopelia orientalis) and crows of the genus Corvus, were photographed both inside and outside the sanitary control zone. This comprehensive quantitative evidence suggests that various mammals and birds may be in indirect contact with livestock, highlighting the need to improve biosecurity at livestock farms. Moreover, while fences are effective against large mammals, they are inefficient against small to medium-sized mammals and birds. Therefore, the results of this study provide important insights into enhancing biosecurity on livestock farms by strengthening physical fencing, disinfecting clothing and equipment, and complying with standards of hygiene management., Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Didecyldimethylammonium chloride (DDAC), a toxic quaternary ammonium compound (QAC) linked to multidrug resistance, is used widely in households and hospitals and on swine farms to prevent disease transmission. However, little is known about its occurrence in watersheds receiving livestock wastewaters or manure. We monitored DDAC and tracers (veterinary and human drugs) once a season over a year at 14 sites in a Japanese watershed where swine outnumbered humans 1.2 to 1 and where both swine and human wastewaters were largely treated on site. DDAC concentrations in sewage-treatment-plant effluent (33-52 ng/L) were close to, whereas those in river waters (3.6-16,672 ng/L) far exceeded, those reported worldwide. DDAC mass flows at the catchment outlet (1692-3816 μg/s) were higher than those of any of the drugs. DDAC concentrations were significantly correlated with total concentrations of veterinary drugs (Spearman's correlation coefficient, 0.95, P < 0.01), indicating that the major pathway of DDAC entry to surface waters was via effluent discharge from swine farms. Comparison of observed and predicted mass flows implied that a substantial percentage of DDAC was washed from the barn floor into swine excrement. To our knowledge, this is the first study to demonstrate QAC hotspots attributable to animal husbandry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Following the Fukushima Daiichi Nuclear Power Plant disaster in March 2011, the Japanese government initiated an unprecedented decontamination programme to remediate 137 Cs-contaminated soils and allow population return. This programme involved the removal of topsoil under farmland and residential land, and its replacement with "fresh soil" composed of granitic saprolite. However, decontamination was limited to these two land uses, without remediating forests, which cover 70 % of the surface area in the affected region. In this unprecedented context, the specific impact of this unique decontamination programme on 137 Cs transfers in river systems remains to be quantified at the catchment scale. In this study, based on the analysis of a sediment core collected in June 2021 in the Mano Dam reservoir draining a decontaminated catchment, the effects of soil decontamination on particle-bound 137 Cs dynamics and sediment source contributions in response to a succession of extreme precipitation events were retrospectively assessed. The sequence of sediment layer deposition and its chronology were reconstructed through the analysis of several diagnostic properties (organic matter, elemental geochemistry, visible colourimetry, granulometry) and contextual information. During abandonment (2011-2016), cropland contribution decreased (31 %). Concurrently, 137 Cs activity and deposition flux decreased (19 and 29%year -1 , respectively). Following decontamination (2017), sediment transfer increased (270 %) in response to increased contributions from decontaminated cropland and "fresh soil" (625 % and 180 % respectively). Meanwhile, forest contributions remained stable. In contrast, 137 Cs activity dropped (65 %), although 137 Cs deposition flux remained constant. Forests acted as a stable source of 137 Cs. Accordingly, 137 Cs deposition flux after decontamination (2016-2021) was similar to that observed during the 5-years period of land abandonment (2011-2016), as a result of the regrowth of spontaneous vegetation over farmland, protecting soil against erosion. Future research should further investigate the impact of longer land abandonment that prevailed in some regions decontaminated lately on the 137 Cs fluxes in the rivers., Competing Interests: Declaration of competing interest Olivier Evrard reports financial support was provided by French National Research Agency. Olivier Evrard reports financial support was provided by French Alternative Energies and Atomic Energy Commission (CEA). Olivier Evrard reports financial support was provided by French National Center for Scientific Research (CNRS). Thomas Chalaux-Clergue reports financial support was provided by French Alternative Energies and Atomic Energy Commission. Thomas Chalaux-Clergue reports financial support was provided by Japan Society for the Promotion of Science (JSPS). Olivier Evrard reports financial support was provided by Environmental Radioactivity Research Network Center (ERAN). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Forty-two Japanese Black cattle on two farms in Kagoshima prefecture, Japan were used in this study. The rearing style of farm A was in a dark barn with a large roof to block sunlight (n=21). The rearing style of farm B was grazing, and exposed to direct sunlight (n=21). Blood sampling was performed twice on the same cattle in August 2022 (summer) and February 2023 (winter). As the results, the serum 25(OH)D 3 concentrations were significantly lower in cattle of farm A than in cattle of farm B (P<0.01), and were significantly lower in winter season than in summer season (P<0.01). These results showed that there were differences in blood 25(OH)D 3 concentrations between the farms or seasons.

Estimation of the soil organic carbon (SOC) stock based on the monitoring data is important to validate the carbon model estimates and provide the initial values of SOC stock to the model. The Japanese National Greenhouse Gas Inventory Report (NIR) has applied the RothC model since 2015 to report changes in SOC in agricultural land. This study estimated soil carbon and nitrogen stocks and C:N ratio of top 30 cm arable land in Japan using the 2015–2018 database of the national soil monitoring project. Estimates based on the stationary monitoring data from the top 30 cm of the soil layer arethe first public release. We modified categorization of the soil temperature regime and soil-type classification for estimation, expecting to mitigate the underestimation and overestimation of SOC stock in the areas of soil temperature 15–17°C and more than 17°C, respectively, and to optimize the soil classification to 16 fewer types to allow an appropriate estimation even in the current situation of decreasing number of survey sites. Statistical analysis to see the effects of land use and soil temperature on SOC stock, TN stock, and C:N ratio showed that soil types other than Andosols had an inverse temperature-dependent trend for all variables, while Andosols had an unclear trend in soil temperature, supporting existing studies. Also, when Lowland soils (Fluvisols or Anthrosols in the World Reference Base) were surrounded by Andosols, redeposition of volcanic ash could affect the temperature trend in SOC stock for Lowland soils. The distribution map of the SOC stock and C:N ratio across Japan visually showed a high value in the Andosols distribution areas and a temperature-dependent trend at the distribution areas of the other soil types. The total SOC stock estimated in this study was 176±12.8 TgC in paddy field, 100±8.6 TgC in upland field, 25±1.7 TgC in orchard, 78±8.9 TgC in grassland, and 379±17.9 TgC in total, the standard deviations of which were much smaller than those of the mean values for each land use calculated by the simple average method. [ABSTRACT FROM AUTHOR]

Agricultural land accounts for 37% of the world's terrestrial area, and the multiple functions of agroecosystems—providing food, soil and water retention, and various cultural services—are of great importance for sustainable land management. To ensure that multifunctionality, payment for ecosystem services (PES) schemes have been developed for heterogeneous agroecosystems. However, the effects of the schemes have not been fully measured because, in most cases, they have been implemented as action-oriented programs rather than outcome-based payments. This study examines the effect of a community-based PES (CB-PES) program on the prevention of farmland abandonment to assess the agricultural outcomes of PES implementation in hilly and mountainous areas in Japan. We interviewed farmers in enrolled communities, mapped enrolled plots, and analyzed agricultural census data on the socioeconomic characteristics and farmland management conditions of 12,261 farmers in 960 agricultural communities in a typical hilly and mountainous area of Noto Peninsula in northern Japan. The results confirm that direct payments are effective in enhancing community management and in preventing additional farmland abandonment. In addition, we found that several socioeconomic and environmental factors at both the community and farmer levels—including geographical conditions, collective management activities, absence of successors, farm scale, and off-farm income dependency—simultaneously affected the farmland abandonment process. Specifically, collective practices within and between communities is a significant factor in preventing farmland abandonment more than collaboration with outsiders. Considering the depopulation and aging of rural communities throughout Japan, intercommunity enrollment could improve the effectiveness of CB-PES by upscaling the current payment scheme to maintain community functions. [ABSTRACT FROM AUTHOR]

The golden mussel Limnoperna fortunei (Dunker, 1857) is an invasive freshwater bivalve species that exerts harmful effects on the environment, as well as man-made structures, such as water-treatment systems. By using conventional sampling methods, it is difficult to detect mussels under low-density conditions; however, environmental DNA (eDNA) analysis may be a rapid and efficient method for monitoring this aquatic organism. In this study, we conducted surveys based on the eDNA analysis of L. fortunei in 15 farm ponds in Japan and compared the results with those of two conventional survey methods, visual census and plankton larval survey, to clarify the effectiveness of eDNA analysis for field surveys of L. fortunei. Primers and a probe specific to L. fortunei were developed, and a method for analysis was established. In the laboratory experiments, the species eDNA was detected in all water tanks containing the mussels, and the concentration of eDNA was high in the experimental tank that had high density of L. fortunei. In the field survey, L. fortunei eDNA was detected in all ponds where the mussels were found by conventional survey, and low concentrations of eDNA were also detected in several ponds where no L. fortunei were found by traditional methods. These results suggest that eDNA analysis has greater sensitivity for the detection of L. fortunei in farm ponds than that of conventional methods. Environmental DNA surveys have little impact on water management and are suitable for surveys at water facilities that have not yet been damaged by the mussels. [ABSTRACT FROM AUTHOR]

Fertilizer-derived P is accumulated in cropland soils and their phytoavailability is variable depending on the speciation of P, which is affected by soil properties. In this study, we aimed to clarify how soil properties affect the speciation of P accumulated in fertilized soils. Soil samples were collected from the cultivated soil layers of 137 vegetable fields in Aichi prefecture, Japan. The speciation of soil P was evaluated by Truog method, sequential extraction by acetic acid, NH4F, and NaOH (Sekiya method), P K-edge X-ray adsorption near-edge structure (XANES). Phosphorus accumulated in cropland consisted predominantly of the inorganic form. Phosphorus extracted by the Truog method and acetic acid was correlated with exchangeable Ca and total C. The XANES analysis indicated that the P species extracted by Truog and acetic acid were associated with Ca, while those extracted by acetic acid also included crystalized calcium phosphate with higher crystallinity than CaHPO4, for example, hydroxyapatite. Due to the high application of P fertilizer and manure with lime, P was accumulated as calcium phosphate except for soils with relatively high contents of oxalate extractable Al and Fe. The amounts of NH4F-extracted P were higher in soils with larger amounts of oxalate extractable Al and Fe. Based on the XANES analyses, the P species extracted by NH4F were associated with Al and Fe, which is inconsistent with the operational definition of NH4F-soluble species. The P in soils extracted by NaOH was correlated with various soil properties, especially with clay content. The P species extracted by NaOH could not be identified. Our results revealed that the important factors controlling available P associated with Ca were total C and exchangeable Ca, whereas those controlling the P extracted by NH4F were oxalate extractable Al and Fe, because this fraction of P was associated with Al and Fe. [ABSTRACT FROM AUTHOR]

Improving the efficiency of machinery utilization is crucial in modern arable farming. As farms expand in scale, they need more machines, and more complex forms of organization are required to manage the appropriate and efficient utilization of an increasing number of machinery. In this study, we investigated relatively large‐scale rice farms in Japan and assessed the relationship between the types of organization and farm attributes, such as farmland conditions and human resources. While adjusting this effect with propensity scores, we then estimated how the type of organization affects the number of major machines and machine workdays. When compared on a same‐scale, same condition basis, family farms were the most sparing in the use of machinery, and even the farmland concentration effect, achieved by community farms, could not compensate for this difference. Our findings also indicated that nonfamily farms achieved high levels of machinery utilization with a greater operational scale (L23, M11, Q12). [ABSTRACT FROM AUTHOR]

Mammalian orthoreoviruses (MRVs), belonging to the genus Orthoreovirus in the family Spinareoviridae, possess a double-stranded RNA segmented genome. Due to the segmented nature of their genome, MRVs are prone to gene reassortment, which allows for evolutionary diversification. Recently, a genotyping system for each MRV gene segment was proposed based on nucleotide differences. In the present study, MRVs were isolated from the fecal samples of Japanese Black cattle kept on a farm in Japan. Complete genome sequencing and analysis of 41 MRV isolates revealed that these MRVs shared almost identical sequences in the L1, L2, L3, S3, and S4 gene segments, while two different sequences were found in the S1, M1, M2, M3, and S2 gene segments. By plaque cloning, at least six genetic constellation patterns were identified, indicating the occurrence of multiple inter- (S1 and M2) and intra- (M1, M3, and S2) reassortment events. This paper represents the first report describing multiple reassortant MRVs on a single cattle farm. These MRV gene segments exhibited sequence similarity to those of MRVs isolated from cattle in the U.S. and China, rather than to MRVs previously isolated in Japan. Genotypes consisting solely of bovine MRVs were observed in the L1, M1, and M2 segments, suggesting that they might have evolved within the cattle population., (© 2024. The Author(s).)

Infectious bursal disease (IBD), caused by IBD virus (IBDV), is highly contagious, immunosuppressive and causes a negative economic impact on poultry industry. IBDV-vaccinated broiler farms at south Kyushu, Japan had a bursa-to-bodyweight ratio (BB ratio) reduction at 28 days (d) old, followed by high mortality 30 d later. We analysed the influence of the IBDV on atrophy of the bursa of fabricius (BF) and the subsequent mortality after 30 d. Ten broilers were sampled at each timepoint from the farm with high mortality at 21, 25, 28 and 35 d. A second flock from the same farm was sampled at 14, 21, 25, 28, 35 and 42 d. IBDV was detected in BF samples at 25, 28 and 35 d and at 21, 25, 28 and 35 d in the first and second flocks, respectively, using immunohistochemical staining and RT-PCR. IBDV isolates from both flocks were closely related to the China KM523643 strain. Histopathology and TUNEL assay indicated apoptosis, severe lymphoid depletion, vacuoles within follicles, lymphoid follicle atrophy and fibrosis in the BF. We observed 75% of the polyserositis and 10% of the airsacculitis at 30 D in dead broilers. The antigenic variant IBDV infection was appeared to be the main influencing factor on BF atrophy and BB ratio reduction in the broilers. High mortality in the broilers after 30 d could be due to secondary infection. The disease caused by IBDV had a negative economic impact in the farm. RESEARCH HIGHLIGHTS New variant IBDV caused bursa atrophy and reduced BB ratio in 28-day-old broilers. After vIBDV had infected broilers, at 21 days old they became immunosuppressed. High mortality at 30 days old in broilers was due to secondary infection. New vIBDV has a negative economic impact on broiler farms in Japan. [ABSTRACT FROM AUTHOR]

Agricultural management practices such as cover crop could restore soil physical and chemical properties, and in turn positive effect of crop productivity. However, it can vary with soil type, climate, and type of cover crop species. In addition, different cover crops provide different benefits to agricultural land. For instance, legumes (e.g. clover (Trifolium repers L.)) fix atmospheric nitrogen (N) for their own use. After terminating the legume cover crop, it will release N into the soil as the residues decompose and provide available N to the main crops. Some of cover crop (e.g. phacelia (Hydrophylloideae)) are able to suppress weeds or prevent insect damages by competition, shading, and allelopathy. Recently, researchers reported that cover crop mixture may provide greater diversity of benefits than monoculture cover crop. Therefore, the objective of this study was to demonstrate soil physical and chemical properties assessment under cover crops (clover, phacelia, and their mixture) vegetation. [ABSTRACT FROM AUTHOR]

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The emu is a novel poultry species in Japan. However, Japanese farmed emu populations have reduced genetic diversity owing to inbreeding. We have previously suggested that there are genetic resources in the Tohoku Safari Park (TSP) and Fuji/Kakegawa Kachoen Garden Park (FGP/KGP) to extend the genetic diversity of commercial emu farms based on microsatellite (SSR) and mitochondrial DNA. However, those markers provide relatively poor information. Thus, we investigated the genetic structure of farmed Japanese populations based on a large-scale genotyping system using RAD-seq and verified the usefulness of TSP and FGP/KGP as genetic resources for expanding genetic diversity. Admixture, phylogenetic, and principal component analyses based on 28,676 SNPs showed that TSP individuals were ancestors in the Okhotsk Emu Farm (OEF). FGP/KGP individuals showed a unique genetic component that differed from that of the others. We have previously reported that the mitochondrial haplotypes of FGP/KGP were shared with an isolated wild population in eastern Australia. These results suggest that FGP/KGP individuals originated from an eastern Australia isolated population different from other populations including ancestral of OEF/TSP. Our results would provide information for the development of Japanese emu farms and industry and for the conservation of genetic resources in the Australian wild emu., (© 2024. The Author(s).)

In Japan, outbreaks of H5N8 highly pathogenic avian influenza (HPAI) were reported between November 2020 and March 2021 in 52 poultry farms. Understanding HPAI epidemiology would help poultry industries improve their awareness of the disease and enhance the immediate implementation of biosecurity measures. This study was a simulation-based matched case-control study to elucidate the risk factors associated with HPAI outbreaks in chicken farms in Japan. Data were collected from 42 HPAI-affected farms and 463 control farms that were within a 5-km radius of each case farm but remained uninfected. When infected farms were detected as clusters, one farm was randomly selected from each cluster, considering the possibility that the cluster was formed by farm-to-farm transmission within an epidemic area. For each case farm, up to three control farms were selected within a 5-km radius. Overall, 26 case farms (16 layer and 10 broiler farms) and 75 control farms (45 layer and 30 broiler farms) were resampled 1000 times for the conditional logistic regression model with explanatory variables comprising geographical factors and farm flock size. A larger flock size and shorter distance to water bodies from the farm were found to increase infection risk in layer farms. Similarly, in broiler farms, a shorter distance to water bodies increased infection risk. On larger farms, frequent access of farm staff and instrument carriages to premises could lead to increased infection risk. Waterfowl visiting water bodies around farms may also be associated with infection risk., Competing Interests: Declaration of competing interest none., (Copyright © 2023. Published by Elsevier Ltd.)

Objectives: Linezolid is a last-resort antimicrobial in human clinical settings to treat multidrug-resistant Gram-positive bacterial infections. Mobile linezolid resistance genes (optrA, poxtA, and cfr) have been detected in various sources worldwide. However, the presence of linezolid-not-susceptible bacteria and mobile linezolid resistance genes in Japan remains uncertain. Therefore, we clarified the existence of linezolid-not-susceptible bacteria and mobile linezolid resistance genes in farm environments in Japan., Methods: Enterococci isolates from faeces compost collected from 10 pig and 11 cattle farms in Japan in 2021 were tested for antimicrobial susceptibility and possession of mobile linezolid resistance genes. Whole-genome sequencing of optrA and/or poxtA genes positive-enterococci was performed., Results: Of 103 enterococci isolates, 12 from pig farm compost were not-susceptible (2 resistant and 10 intermediate) to linezolid. These 12 isolates carried mobile linezolid resistance genes on plasmids or chromosomes (5 optrA-positive Enterococcus faecalis, 6 poxtA-positive E. hirae or E. thailandicus, and 1 optrA- and poxtA-positive E. faecium). The genetic structures of optrA- and poxA-carrying plasmids were almost identical to those reported in other countries. These plasmids were capable of transferring among E. faecium and E. faecalis strains. The optrA- and poxtA-positive E. faecium belonged to ST324 (clade A2), a high-risk multidrug-resistant clone. The E. faecalis carrying optrA gene on its chromosome was identified as ST593., Conclusions: Although linezolid is not used in livestock, linezolid-not-susceptible enterococci could be indirectly selected by frequently used antimicrobials, such as phenicols. Moreover, various enterococci species derived from livestock compost may serve as reservoirs of linezolid resistance genes carried on globally disseminated plasmids and multidrug-resistant high-risk clones., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

We examine the effect of direct payments in less-favoured areas (LFAs) on agricultural land use and farm numbers in Japan, using community-level panel data. Direct payments, which take a unique form in Japan, are made to rural communities that have sloping farmland and are designated as 'less-favoured'. We exploit whether a community is located in a designated area as an instrument for receipt of direct payments. Our instrumental variable estimates find that, although LFA payments fostered continued land use and prevented farmland abandonment through maintenance of farm households and household members, these effects are modest. [ABSTRACT FROM AUTHOR]

The objectives of this study were to assess abortion risk (AR) and the number of piglets that died during suckling periods per litter (DP) in farms infected with porcine epidemic diarrhea (PED) in relation to herd immunization procedures. Data were obtained from 91 farms in Japan that had PED infection during 2013 to 2014. The 91 PED-positive farms were asked the number of abortions that occurred and DP for 3 months (1 month before PED outbreak (previous month), 1 month after PED outbreak (the month of PED), and from 1 month after PED outbreak to 2 months after PED outbreak (following month)). AR in each month was calculated as the number of abortions divided by sow inventory. Both AR and DP in the month of PED were higher than those in the previous and following months (p < .05). Farms that performed a herd immunization procedure had higher AR and DP in the month of PED than those that did not perform the procedure (p < .05). In summary, PED occurrence increased AR and DP. [ABSTRACT FROM AUTHOR]

In the face of climate-related challenges in agriculture, Japan's 'Direct Payment for Environmentally Friendly Farming' policy stands as a proactive effort to incentivize sustainable practices among smallholder farmers. This study evaluates the policy's impact on smallholder farmers' net farm income within the Tohoku Region, employing a propensity score matching (PSM) methodology to analyze survey data encompassing household-specific attributes and engagement with the policy. Our results indicate that participation in the direct payment scheme enhances farmer income, averting an estimated reduction of 125 thousand JPY per annum. While direct payments demonstrated a positive effect on smallholder income, our findings surprisingly revealed that skill training, a key non-financial support, had a negligible impact on household earnings. The findings highlight the policy's efficacy in promoting practices that decrease reliance on chemical inputs and increase organic farming, thereby contributing to carbon emissions mitigation. Notably, our analysis suggests that subsidies directed towards integrating renewable energy on farms may have a less immediate financial impact compared to other forms of support. This research underscores the complex interplay between agricultural subsidies, environmental sustainability, and farmer income, revealing that direct financial incentives are pivotal in fostering climate-conscious agricultural practices among smallholders., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study investigated the effects of parity, season, and the previous lactation's milk yield on fertility in dairy cows. A total of 5,514 calving records for Holstein cows that calved between 2016 and 2018 on a single large dairy farm in Japan were used for analysis. The proportion of cows that get pregnant by 360 days after calving was defined as the percentage of all cows eligible for breeding that became pregnant. In the all-cow model, pregnancy probability associated with both parity and calving season (p < 0.05). Pregnancy probability decreased with an increase in parity, with hazard ratios (HRs) of 1.75 (1.58-1.94) for parity 1, 1.25 (1.13-1.39) for parity 2, 1.15 (1.04-1.29) for parity 3, and 1.13 (1.00-1.27) for parity 4, relative to parity ≥5. In terms of calving season, the lowest pregnancy probability was found in spring, and the HRs relative to spring were 1.16 (1.07-1.26) for summer, 1.35 (1.24-1.47) for autumn, and 1.17 (1.07-1.27) for winter. In the multiparous-cow model, pregnancy probability associated with the previous lactation's milk yield (p < 0.05), but not with parity or calving season. Cows with high and middle previous milk yields had lower pregnancy probabilities than those with low milk yields., (© 2024 Japanese Society of Animal Science.)

Brown rats (Rattus norvegicus), roof rats (Rattus rattus), and house mice (Mus musculus) are considered to be important pests on livestock farms. Although the diel activity patterns of rodents are key to their control, information on this aspect of their ecology is limited. Furthermore, the effect of carnivores on rodent activity patterns as well as the carnivore species present on livestock farms is unclear. Here, we set camera traps in an open-type cow barn and in an enclosed pig barn on the same livestock farm in Japan from August through October 2021. The only rodents observed in both barns were roof rats, and the carnivore species observed were dogs (Canis familiaris), cats (Felis catus), and Japanese weasels (Mustela itatsi). Roof rats showed different patterns of activity and behavior between the barns. However, because the pattern in both barns was nocturnal, the activity patterns of roof rats and carnivores showed a moderate to high degree of overlap. Therefore, roof rats did not appear to shift their activity patterns to avoid nocturnal carnivores. Taken together, the present study provides valuable information for rodent control on livestock farms in Japan., (© 2024 The Author(s). Animal Science Journal published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Animal Science.)

We performed a parasitological examination of the gastrointestinal tract of farmed ring-necked pheasants (Phasianus colchicus karpowi) on two farms in Ehime, Japan. Fecal examination through flotation and sedimentation methods (43, 103, and 50 samples in three consecutive years from 2020, respectively) detected coccidian oocysts (5-58%), or capillarid (40-56%) and heterakid eggs (45-72%). Following artificial sporology, most sporulated coccidian oocysts were ellipsoidal without micropyle nor residuum, but with 1-3 polar refractile granules, morphologically reminiscent of Eimeria phasiani (Apicomplexa: Eucoccidiorida: Eimeriidae). Intensive sequencing of mitochondrial cytochrome c oxidase subunit I gene (cox-1) using pan-eimerian primers and multiple oocyst samples from different pheasants indicated a single species. We characterized, for the first time, the cox-1 sequence of E. phasiani, known to be prevalent in wild and captive ring-necked pheasants worldwide. Worm recovery under a dissection microscope revealed two capillariid and one heterakid nematode species: Eucoleus perforans (Nematoda: Trichocephalida: Capillariidae) in the esophageal epithelium (prevalence, 8-73%), Capillaria phasianina (Capillariidae) in the cecal mucosa (10-87%), and Heterakis gallinarum (Nematoda: Ascaridida: Heterakidae) in the cecal lumen (69-88%). The small subunit ribosomal RNA gene (SSU rDNA) of E. perforans was perfectly identical to that in a previous isolate from farmed Japanese green pheasants (Phasianus colchicus versicolor) at a distant locality in Japan. The SSU rDNA of C. phasianina was characterized, for the first time, demonstrating a sister relationship with Capillaria anatis, parasites found in the ceca of domestic ducks, geese, and various wild anatid birds., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The objective of this study was to analyze death and culling (DC) of calves during the first month of life and associated economic losses on dairy farms in eastern Hokkaido, Japan. The DC in the first month of life of 4411 Holstein and Wagyu crossbred calves born in the year 2019-2020 on 39 dairy farms milking Holsteins was investigated. Based on a target DC rate of 6.75%, farms were classified into two groups, those with high DC rates (HDC, 11.68%, n = 18) and those with low DC rates (LDC, 2.67%, n = 21), and analyzed for DC factors (breed, sex, parity of dams, and housing type of dams) and diseases causing DC, their loss estimates, and replenishment of DC calves (birth rate, purchase of heifers, and housing type of dams). Comparisons between groups were made using the Kaplan-Meier method, the Mann-Whitney U test, and chi-square test. The DC rate of Holsteins was significantly higher (P < 0.001) for HDC farms than for LDC ones. But, the DC rate of Wagyu crossbreds was not different between the groups, which suggested hybrid vigor. The DC rates for digestive diseases were significantly higher (P < 0.01) in the HDC farms, except for congenital diseases and deaths of unknown cause. The overall loss estimates of DC per calf-month for all farms was 8892, JPY/calf-months, 14,726 for HDC farms, and 4065 for LDC farms. The loss estimates of items with significant differences in DC rates were significantly higher (P < 0.05) in the HDC farms, with higher loss estimates for Holsteins and digestive diseases being the most common characteristics of HDC farms. In binomial logistic regression analysis with "HDC farms or not" as the response variable and replenishment of DC calves as the explanatory variable, HDC was significantly more likely (OR: 1.10, P < 0.05) on farms with a higher birth proportion of Holsteins, and HDC farms supplemented the DC calves by increasing the birth proportion of Holsteins., Competing Interests: Declaration of Competing Interest The authors declare that this study is not supported by any special funds., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The purpose of this study was to clarify the genetic diversity of Phytopythium helicoides and to understand the transmission mode of the pathogen in Japan. In total, 232 P. helicoides isolates were collected from various host plants and geographic origins, including farms and natural environments. We developed 6 novel microsatellite markers for use in the study and found 90 alleles among the 6 markers in the 232 isolates. The analysis of molecular variance suggested that P. helicoides has high variance within individuals and low fixation indices between populations. A phylogenetic analysis revealed that isolates collected from the same hosts and/or geographic origins were often grouped together. For example, several isolates from natural environments were grouped with isolates from nearby agricultural areas. On the other hand, 2 geographically distant populations collected from the same host plant had similar genotypes. Our results suggested that migration of the pathogen could be facilitated naturally via drainage systems or by human activity in the transport of agricultural materials. [ABSTRACT FROM AUTHOR]

Natural disasters have caused enormous impacts on rural societies in both developed and developing countries for the recent years. Due to climate change, the frequency and intensity of extreme weather have increased and it is predicted to be more rampant for the coming decades. As rural societies are mainly dependent on agriculture, the rapid recovery and reconstruction of damaged agricultural lands and infrastructure is crucial to enhance their resilience. The rapid measures and actions in the post-disaster can reduce the impacts and can help farmers save their livelihoods as well as consumers ensure their provisions. This paper focuses on administrative issues in the recovery management in the post-disaster period in Japan. Especially, it takes up the underlying issues that impede the disaster recovery process and the application of Geographic Information System (GIS) and Unmanned Aerial Vehicle (UAV) in case of earthquake and flood disasters including storms and heavy rainfall. The data was collected through questionnaire survey to the agricultural departments in all the prefectural offices in Japan. From the results, the administrative issues were attributed to the complexity of project procedures and documentation, human resources, rural planning, the lack of capacity in construction companies, in most of the prefectures. The use of GIS and UAV was limited in many prefectures due to the lack of knowledge or experience. However, GIS could help the recovery processes quicken for some prefectures. Based on the findings, it is suggested to make a manual about GIS database building which can be shared among prefectural offices and farmers to inherit the past lessons and enhance resilience for the future. [ABSTRACT FROM AUTHOR]

While wetlands have been converted into farmlands, large amounts of farmlands are now being abandoned, and this novel habitat is expected to be inhabited by species which depend on wetlands. Here we examined the effects of habitat and landscape variables on the densities of wetland bird species in abandoned farmlands. We surveyed birds in abandoned farmlands with different patch area, habitat, and landscape variables in Kushiro district, eastern Hokkaido, northern Japan. We also surveyed birds in 15 ha of the remaining wetlands as a reference habitat. We used abundance-based hierarchical community models (HCMs) to estimate patch-level estimates of abundance of each species based on sampling plots data that only partially covered the studied patches. We observed 14 wetland species and analyzed them with HCMs. Abandoned farmland patch areas had significant positive effects on the densities of two species. Tree densities and shrub coverage exerted positive and negative effects on some species. Amounts of surrounding wetland/grassland had positive effects on many species. Ensemble of species-level models suggested that 24.7 and 10.6 ha of abandoned farmlands would be needed to harbor a comparable total abundance and species richness in 15-ha wetlands, respectively. These required amounts can be increased/decreased depending on the covariates. The use of HCMs allows us to predict species- and community-level responses under varied conditions based on incomplete sampling data. A quantity of 1.6 times larger areas of abandoned farmlands may be required to restore wetland bird communities in eastern Hokkaido. [ABSTRACT FROM AUTHOR]

Quercus acutissima Carruth. is an economically important species that has long been cultivated in Japan, so is a valuable subject for investigating the impact of human activities on genetic variation in trees. In total, 2152 samples from 18 naturally regenerated populations and 28 planted populations in Japan and 13 populations from the northeastern part of Eurasia, near Japan, were analyzed using six maternally inherited chloroplast (cpDNA) simple sequence repeat (SSR) markers. Although 23 haplotypes were detected in total, both the Japanese natural and artificial populations exhibited much lower genetic diversity than the continental populations. The level of genetic differentiation among natural populations in Japan was also much lower (G'ST = 0.261) than that on the continent (G'ST = 0.856). These results suggest that human activities, such as historical seed transfer, have reduced genetic diversity within and among populations and resulted in a homogeneous genetic structure in Japan. The genetic characteristics of natural and artificial populations of Quercus acutissima in Japan are almost the same and it is likely that most of the natural populations are thought to have originated from individuals that escaped from plantations. [ABSTRACT FROM AUTHOR]

In the winter of 2021-2022, multiple subtypes (H5N8 and H5N1) of high pathogenicity avian influenza viruses (HPAIVs) were confirmed to be circulating simultaneously in Japan. Here, we phylogenetically and antigenically analyzed HPAIVs that were isolated from infected wild birds, an epidemiological investigation of affected poultry farms, and our own active surveillance study. H5 subtype hemagglutinin (HA) genes of 32 representative HPAIV isolates were classified into clade 2.3.4.4b lineage and subsequently divided into three groups (G2a, G2b, and G2d). All H5N8 HPAIVs were isolated in early winter and had HA genes belonging to the G2a group. H5N1 HPAIVs belong to the G2b and G2d groups. Although G2b viruses were widespread throughout the season, G2d viruses endemically circulated in Northeast Japan after January 2022. Deep sequence analysis showed that the four HPAIVs isolated at the beginning of winter had both N8 and N1 subtypes of neuraminidase genes. Environmental water-derived G2a HPAIV, A/water/Tottori/NK1201-2/2021 (H5N8), has unique polymerase basic protein 1 and nucleoprotein genes, similar to those of low pathogenicity avian influenza viruses (LPAIVs). These results indicate that multiple H5 HPAIVs and LPAIVs disseminated to Japan via transboundary winter migration of wild birds, and HPAIVs with novel gene constellations could emerge in these populations. Cross-neutralization test revealed that G2a H5N8 HPAIVs were antigenically distinct from a G2b H5N1 HPAIV, suggesting that antibody pressure in wild birds was involved in the transition of the HPAIV groups during the season.

Present study provides first comprehensive results on the residual levels of 19 antimicrobial (AM) residues in 12 Japanese swine manure composting facilities that use open or enclosed types of treatment methods. Tilmicosin (14000 μg/kg d.w.) and tiamulin (15000 μg/kg d.w.) were present in the highest concentrations in manure composts. Morantel (MRT) had the highest detection frequency (100%) in compost, suggesting its ubiquitous usage and resistance to degradation during composting. Sulfamethoxazole had low detection frequencies and concentrations, likely due to limited partitioning to the solid phase. A positive correlation (p < 0.05) between purchasing quantities and residue levels in manure composts was detected for fluoroquinolones (FQs). The removal efficiencies of AMs in enclosed-type facilities were lower and more inconsistent than those in open-type facilities. Tetracyclines (TCs), lincomycin, and trimethoprim were easily removed from open-type facilities, whereas FQs and MRT persisted in both facilities. After discontinuing the usage of oxytetracycline (OTC), TCs concentrations reduced drastically in input materials, remained pseudo-persistent in composts for up to 4 months, suggesting a time lag for composting and were not detected (<10 µg/kg) after 4 months of OTC withdrawal. This study emphasizes on the effectiveness of manure composting methods in reducing AM residues in swine waste., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Environmental decontamination after a nuclear disaster not only contributes to reducing the public's exposure to radiation, it also introduces waste disposal issues arising from the decontamination process. In addition to that issue, the optimisation of decontamination efforts necessitates the consideration of various environmental, economic, and societal factors. Stakeholders' perspectives are important for identifying the multifaceted aspects to be considered. We conducted a semi-structured interview survey in 2019 with ten residents in a rural community in Fukushima, Japan, which experienced a six-year-long evacuation due to the 2011 Fukushima Daiichi Nuclear Power Plant accident. The main survey questions addressed returnees' perceptions of the decontamination of farmlands and forests. The 'Steps for Coding and Theorization' procedure was used for qualitative analysis. The analysis illuminated the positive and negative impacts of the decontamination process on the rebuilding of the returnees' rural lives from various perspectives and identified elements to be considered for the optimisation of future remediation efforts. The removal of radioactive materials had a positive psychological impact on the returnees, fostering a sense of security that their crops were safe and instilling confidence that the high-quality environment of the region had been restored. These aspects were not included among the initial governmental objectives for decontamination, which were aimed solely at reducing radiation exposure. By contrast, the removal of fertile topsoil from farmland had a negative impact on the residents, making them hesitant to resume farming. Our findings suggest that emphasising procedural fairness in decision-making of decontamination options such as reflection of stakeholders' opinions led to residents perceiving their post-decontamination situation more positively. Our results provide valuable insights for optimising remediation strategies for the recovery process following a significant nuclear accident., (Creative Commons Attribution license.)