Paddy Fields Research Articles

Zeolite mitigates alternate wetting and drying–induced potassium depletion and enhances potassium balance in rice paddies: a 6-year field study

Context or problemClinoptilolite zeolite has been studied as a means to optimize water and fertilizer use, mitigate potassium (K) loss, increase grain yield, and maintain positive K balances. However, there is limited information on field-aged effects of zeolite, especially under alternate wetting and drying irrigation (AWD). Objective or research questionThis study aimed to determine field-aged effects of zeolite on soil exchangeable K (SEK) and soil non-exchangeable K (NEK), K leaching, aboveground K uptake, water use efficiency (WUE), apparent K balance (AKB), soil K balance (SKB) and income of paddy field were analyzed under continuous flooding irrigation (CF) and AWD. MethodsWe conducted a six-year (2017–2022) field experiment with two irrigation regimes (CF and AWD) as main plots and zeolite addition at the rate of 0 (Z0) and 10 (Z10) t ha-1 as subplots. ResultsThe results showed that AWD significantly increased soil NEK (0.65kgha-1 in 2022) and decreased AKB2017-2019 (75.11%), AKB2017-2022 (76.26%), SKB2017-2019 (4.75kgha-1) and SKB2017-2022 (11.25kgha-1), respectively. Zeolite addition to paddy fields could decrease K leaching loss, increase soil exchangeable K, K balances and net income endured for six years, especially under AWD. Compared to ICFZ0, IAWDZ0 respectively decreased apparent K balance (AKB2017-2022) and soil K balance (SKB2017-2022) by 19.73% and 15.09%. Compared to Z0, Z10 respectively increased AKB2017-2019 and SKB2017-2019 by 48.51% and 243.61% and respectively increased AKB2017-2022 and SKB2017-2022 by 47.47% and 112.87%. IAWDZ10 has the highest AKB both in 3-yr aged field and 6-yr aged field, the highest soil NEK in 6-yr aged field. ConclusionsOverall, the combination of zeolite and AWD technology improved K balances and addressed the accelerated deficit of effective K in paddy fields under AWD. These positive effects persisted for 6 years, exceeding the originally observed 3-yr duration, suggesting zeolite has a long-life cycle and potential in rice production systems. IMplications or significancezeolite application can mitigate K depletion for at least six years, especially under AWD, promoting sustainable agriculture development and income of paddy field.

Implications of water management on methane emissions and grain yield in paddy rice: A case study under subtropical conditions in Brazil using the CSM-CERES-Rice model

Implications of water management on methane emissions and grain yield in paddy rice: A case study under subtropical conditions in Brazil using the CSM-CERES-Rice model

Converting paddy to upland alters soil neutral sugars by influencing microbial community and life history strategy

Neutral sugars, derived from plants and microorganisms, are essential components of the labile soil organic carbon (SOC) pool, serving as crucial C and energy sources for soil microorganisms and influencing the accumulation and stability of SOC. However, the extent and mechanisms of the change of soil neutral sugars after converting paddy fields to upland, remain unclear. This study investigated the effects of converting paddy fields to upland (vegetable and jasmine fields) on soil microbial communities and neutral sugars in Fuzhou, Fujian province, subtropics China. We found that the conversion of paddy fields (anaerobic) to uplands (aerobic) significantly decreased neutral sugars and altered their composition, while increasing the relative proportion of microbial-derived sugars (e.g., galactose and mannose). Compared to paddy soil, the total neutral sugars were reduced by 20.6–51.9 %, and microbial diversity was also reduced, shifting dominant species from r-strategists to K-strategists in vegetable and jasmine field soil. These results suggest that the conversion of paddy fields to uplands is unfavorable for soil C sequestration, but potentially enhance the soil C stability. Random forest and correlation analyses indicated that the changes in soil microbial community composition and life history strategies significantly influence the concentrations and composition of neutral sugars in soils. Overall, these findings underscore the critical roles of microbial diversity and life strategies in shaping soil C dynamics, suggesting that the agriculture practices that promote microbial diversity and support K-strategists may enhance soil C stability and sequestration.

A comparative assessment of grey water footprint estimation methods in paddy fields

A comparative assessment of grey water footprint estimation methods in paddy fields

Tetrachlorantraniliprole induces neurodevelopmental toxicity through oxidative stress-mediated apoptosis and dysregulation of Wnt signaling pathway.

Tetrachlorantraniliprole (TCTP) is a novel bisamide insecticide and widely used to protect against lepidopteran insect species. However, the application of TCTP in rice fields often leads to water pollution, posing threats to aquatic organisms and potentially to human health. Few studies have assessed the toxic effects of TCTP on aquatic animals. In this study, we used zebrafish as a model organism to evaluate the toxicity of TCTP. Our findings indicated that TCTP adversely affected the development of zebrafish larvae, impacting parameters such as heart rate, body length, and pericardial edema. Exposure to TCTP resulted in the increased embryo mortality along with higher concentrations of the compound. The expression of neurodevelopment-related genes was inhibited in embryos exposed to TCTP. Hematoxylin and eosin (HE) staining revealed that TCTP caused damage to the brain cells of the embryos. Behavioral analysis showed a reduction in activity of the larvaes, which aligned with a decrease in acetylcholinesterase (AChE) activity. Additionally, RNA sequencing (RNA-seq) was employed to elucidate the mechanisms of toxicity. GO and KEGG analysis identified that the pathways were related to oxidative stress, apoptosis and Wnt signaling. We observed an increase of reactive oxygen species (ROS) and Ca²/Mg²-ATPase activity, while antioxidant enzyme activities (SOD, MDA, CAT, Na/K-ATPase and T-ATPase) were significantly decreased in TCTP-exposed groups. Furthermore, TCTP induced brain cells apoptosis, as evidenced by the upregulation of pro-apoptotic genes (bax, p53, TNFα, caspase3 and caspase9) and the downregulation of anti-apoptotic gene (bcl2). Moreover, TCTP increased the expression of genes involved in Wnt signaling pathway. Notably, oxidative stress and neuronal damage induced by TCTP could be mitigated by astaxanthin, an antioxidant. Additionally, IWR-1, an inhibitor of Wnt signaling pathway, effectively alleviated the upregulation of genes associated with TCTP treatment and inhibited oxidative stress-induced apoptosis. In conclusion, this study demonstrated TCTP-induced defects of neurodevelopment and the brain cells in zebrafish larvae which were primarily driven by oxidative stress-induced apoptosis and dysregulation of Wnt signaling pathway. Importantly, these toxic phenotypes can be rescued by treatment with astaxanthin or IWR-1.

Effects of crop rotation and straw return on soil microbiome in a southern paddy field

Effects of crop rotation and straw return on soil microbiome in a southern paddy field

Degradation of Oxolinic Acid in Soil Under Simulated Natural Degradation Processes

Oxolinic acid (OA), a quinolone-class antibiotic commonly used in domestic agriculture, exhibits low bioavailability, raising concerns about its potential environmental persistence. Residual OA in the environment can undergo partial degradation through natural processes, which are influenced by various factors. This study aimed to investigate the photodegradation and biodegradation patterns of OA under various environmental factors, including temperature, light intensity, soil usage, soil organic matter content (OM). Additionally, adsorption and desorption experiments were conducted to elucidate the relationship between OA degradation and its adsorption-desorption behavior in soil. In this study, two UV-A intensities (2.3 and 1.5 mW cm<sup>-2</sup>) and two temperatures (21.8 and 35.0<sup>o</sup>C) were applied to examine the OA degradation behavior. Biodegradation tests were conducted using soil samples with varying land uses (rice paddy, field) and OM (6.4% and 2.3%). Additionally, sorption tests were performed using the soil samples and OA solutions, followed by desorption tests on the OA-sorbed soil samples. In the photodegradation experiment, the OA degradation rate ranged from 16.6% to 51% across all conditions after 20 d. Compared to other antibiotics reported in previous studies, OA exhibited relatively slow photodegradation, and the variations in degradation rates under the tested experimental conditions were not statistically significant. In the case of biodegradation, similar degradation rates were observed in the field and rice paddy soils, with faster degradation occurring in soils with lower OM. The differing biodegradation patterns observed across soil samples could be partially explained by the adsorption-desorption characteristics of OA in soils. The degradation of antibiotics through simulated natural processes such as photodegradation and biodegradation did not exhibit consistent trends depending on the environmental factors or soil properties. This suggests that the degradation of antibiotics is a complex process influenced by various factors, including, but not limited to, environmental factors and soil properties. This study highlights the need for further research to better understand the behavior of residual antibiotics in soil environments.

Diversity and dynamics of insect pests of paddy rice stored in the city of Issia; Central-West of Côte D’Ivoire

Paddy rice stocks are attacked by pests that sometimes cause enormous damage. This study aims to assess the diversity and abundance of insect pests of stored paddy rice in the city of Issia. Three samples in three kilograms were taken per bag at different levels of the bag and sorted manually in three stores in the city. The collected insects were examined using a Binocular magnifying glass in the laboratory. Overall, 4867 insects were inventoried. They are all beetles belonging to three families; Bostrichydae (Rhyzoperta dominica); Tenebrionidae (Tribolium chestnut); Curculiondae (Sitophilus oryzae L and Sitophilus zeamais). Data analysis showed that Tenebrionidae slightly predominate with 36.78%; followed by Bostrichydae with 35.63% and finally Curculiondae with 27.59. The study revealed that environmental conditions and storage duration influence the multiplication and evolution of insect populations in stocks.

Study of Load Measurement and Analysis on Tractor in Indonesia (Dry Paddy Fields)

Study of Load Measurement and Analysis on Tractor in Indonesia (Dry Paddy Fields)

Comparative assessment of exposure tools to estimate pesticide concentrations in rice paddies: a discussion of the Brazilian context.

Estimating pesticide concentrations in paddy rice systems is challenging due to unique cultivation methods and water management practices. Various models, ranging from simple exposure calculators to complex scenario-dependent tools, have been developed globally to address this issue (PADDY, MED-Rice, RICEWQ, PFAM). In Brazil, pesticides are used in paddy rice production, and there is a potential risk of these compounds reaching waterbodies. Legislative changes in 2023 made environmental risk assessment mandatory for pesticide registration in Brazil. However, Brazil has not officially adopted a specific modelling tool for paddy rice systems. This critical review evaluates (i) the strengths and limitations of pesticide exposure models for paddy rice most commonly used in Europe, North America, Asia and Latin America; (ii) it reviews the tools used in a regulatory context outside Brazil; (iii) it discusses exposure tools used in lower tiers and then proceeds to a discussion of more sophisticated tools used in higher tiers; (iv) provides and overview of paddy rice production system in Brazil, (v) performs a comparative analysis of the features of each exposure tool against the characteristics of the Brazilian paddy rice production system, and finally, this review (vi) discusses which exposure tools may be most appropriate for integration into a prospective regulatory ERA framework in Brazil. The goal of this review is to contribute to the ongoing regulatory changes and discussions by identifying appropriate models that can effectively assess the environmental risks associated with pesticide use in Brazilian paddy rice cultivation.

Unveiling carbon dynamics in year-round waterlogged pond fields: insights into soil organic carbon accumulation and sustainable management

Agri-ecosystems with flooded fields are pivotal in global carbon (C) dynamics. Although extensive research has focused on carbon sequestration in paddy fields, year-round waterlogged pond fields remain underexplored. This study investigates carbon dynamics in pond fields planted with Semen Euryales for 0, 24, and 60 years, examining soil organic carbon (SOC) accumulation and shifts in its composition. The results revealed a progressive increase in SOC, driven by particulate organic C (POC) and mineral-associated organic (MAOC). SOC increased significantly from 7.49 g kg–1 to 46.10 g kg–1 over the 60 years, with particulate organic carbon (POC) rising from 12.0% to 42.0% and mineral-associated organic carbon (MAOC) decreasing from 87.8% to 58.0%. Lignin phenols, reflecting plant-derived carbon, surged from 11.0% to 68.8%, while amino sugars, indicative of microbial residues, declined from 89.0% to 31.2%, suggesting reduced microbial activity under prolonged anaerobic conditions. Total microbial phospholipid fatty acid (PLFA) decreased by 40.6% and 43.8% after 24 and 60 years, respectively, further supporting the conclusion that anaerobic conditions limit microbial survival. The prolonged waterlogging reduced microbial decomposition, enhancing the accumulation of POC, particularly from plant-derived carbon such as Semen Euryales residues. The accumulation of microbial residues, especially fungal necromass, played a significant role in forming MAOC. That is, continuous waterlogging promoted POC accumulation and also contributed to MAOC stabilization. The findings provide valuable insights into sustainable carbon management practices in pond fields and contribute to climate change mitigation.Graphical

Short-Term Phosphorus Fertilization Alters Soil Fungal Community in Long-Term Phosphorus-Deprived Yellow Soil Paddy Fields

Short-Term Phosphorus Fertilization Alters Soil Fungal Community in Long-Term Phosphorus-Deprived Yellow Soil Paddy Fields

Estimation of Surface–Subsurface Irrigation Water Use and Scheduling for Sustainable Boro Paddy Cultivation under Canal Command Area of Damodar Valley Corporation (DVC) in India

Estimation of Surface–Subsurface Irrigation Water Use and Scheduling for Sustainable Boro Paddy Cultivation under Canal Command Area of Damodar Valley Corporation (DVC) in India

Morpho-Physiological Adaptations of Rice Cultivars Under Heavy Metal Stress: A Systematic Review and Meta-Analysis

Soil contamination, including in rice fields, arises from a variety of natural processes and anthropogenic activities, leading to an accumulation of heavy metals. While extensive research has addressed the bioaccumulation of heavy metals in rice, only limited systematic reviews have examined their specific impact on the morpho-physiological traits of rice plants. This review aims to provide a comprehensive synthesis of current studies detailing the rice cultivars, types of heavy metals investigated, study designs, sampling locations, and experimental sites while systematically analyzing the morphological and physiological responses of rice cultivars to heavy metal stress. Studies show that morphological traits generally exhibit a decline under heavy metal exposure. Physiologically, rice cultivars tend to show decreased total chlorophyll and carotenoid levels, along with increased levels of malondialdehyde (MDA), hydrogen peroxide (H₂O₂), and antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and proline. These findings suggest that plant genotype, type of heavy metal, and intensity of stress significantly modulate the morphological and physiological responses of rice, highlighting critical areas for further research in heavy metal stress tolerance in rice cultivars.

Grapevine, stone fruit, and tree nut crop response to simulated tetflupyrolimet drift

Abstract Off-target rice herbicide drift is historically a concern in California, where susceptible crops such as orchards and vineyards are nearby. Tetflupyrolimet is a potent inhibitor of dihydroorotate dehydrogenase which provides excellent grass weed control in rice cropping systems. In efforts to steward tetflupyrolimet before its registration in California, this research was conducted to compare the onset of foliar symptoms from tetflupyrolimet applications onto almond, grapevine, peach, pistachio, plum, and walnut. Tetflupyrolimet was applied to these tree and vine crops at fractional rates of 1/200×, 1/100×, 1/33×, and 1/10× of the 125 g ai ha–1 rice use rate. Almond, pistachio, and walnut trees also received the 1× of the rice use rate. Tetflupyrolimet treatments were applied on one side of 3- to 4-yr-old almond, peach, pistachio, plum, and walnut trees and on one side of 25- to 26-yr-old grapevines in 2022 and 2023. Visible injury ratings were carried out weekly to assess symptomology throughout the growing seasons and at leaf out the following springs. Tree trunk diameter was recorded before and after herbicide applications. No injury was observed on any crops tested, regardless of the tetflupyrolimet application rate. In all orchard crops, tree trunk diameter was not affected by tetflupyrolimet treatments. Likewise, grape yield was not reduced even at the 1/10× tetflupyrolimet fractional rate. Since no injury symptoms were recorded, this research suggested that tetflupyrolimet can be safely used at nearby rice fields and might be a target for future registration consideration in orchard and vineyard crops.

Analysis of the Water Quality of the Iwan River in Darmaji Village, Kopang District, Central Lombok Regency

The Iwan River is one of the rivers in Darmaji Village, Kopang District, Central Lombok Regency. People often use This river for daily life, washing, bathing and irrigating rice fields. People also throw household waste into river water bodies. This hamlet does not yet have clean water and a PDAM network. This research uses the pollution index method to determine the water quality of the Iwan River in Darmaji Village and the water quality status of the Iwan River in Darmaji Village. The research method used is quantitative research with an experimental approach according to Government Regulation Number 22 of 2021 and Water Quality Status with the Pollution Index. Based on the results of the Iwan River water quality, it is still below quality standards, so it is still safe for washing and agricultural activities; namely, in upstream samples, there are TSS results of 0.724 mg/L, temperature 26.8, pH 7, BOD 0.5 mg/L, COD 8 mg/L, oil and fat 1.518 mg/L and total Coliform 24000 MPN/ml while the middle sample had TSS results of 1.574mg/L, Temperature 26.7, pH 6, BOD 1.1mg/L, COD 4mg/L, oil and fat 0.066 mg/L, and total Coliform 930 MPN/ml. In downstream samples, there were TSS results of 1.68 mg/L, Temperature 26.8, pH 7, BOD 0.5 mg/L, COD 12mg/L, oil and fat 0.108mg/L and total Coliform 230MPN/ml and Based on the Pollution Index calculation results, the Iwan River is polluted (lightly polluted) but still safe to use for agriculture.

Soil permeability shaping ARGs patterns by affecting soil available nutrients in paddy fields.

Though the evidence for soil property could influence the antibiotic resistance genes (ARGs) profiles is mounting, studies regarding the effect of soil permeability on soil ARGs patterns are still ignored. This study investigated the dynamic distribution of ARGs in paddy fields with different soil permeability over various rice growing stages, as well as revealed the abiotic and biotic factors that shaping ARGs profiles. Results indicate that soil with high permeability improved the ARGs abundance through elevating the available nutrients in the soil. The ARGs abundance trend across rice growth stages was consistent in different zones (decreasing at heading, increasing at maturity), with high-permeability soil showing minimal variation. The partial least-squares path model (PLS-PM) revealed that soil available nutrients (e.g., AP and NH4+-N) and potential hosts (e.g., Bradyrhizobium and Serratia) play key roles in driving ARGs dynamics in soils with varying permeability. Meanwhile, increased permeability stabilized ventilation conditions, raising redox potential (Eh) in flooded soils, thus reducing the variation rate of ARGs in soil. This study offers important insights into the dissemination of ARGs in paddy fields across different levels of soil permeability.

Gambut Muslim Community and Their Environmental Conservation; Intertwin among Fiqh, Economy, and Policy Factors

Islamic eco-theology doctrines encourage believers to care for the environment and forbids destructive actions that could harm or degrade the environmental condition. However, in recent years, many paddy fields and peatlands in Banjar Regency, which should have been preserved for environmental restoration, have been transformed into residential areas. Therefore, this research aims to explore factors influencing the conversion in the Gambut Subdistrict, Banjar Regency, ranging from a religious perspective or fiqh, the economic situation of local people, and relevant regulation enforcement. The research is a field study with a mixed-method approach. Data collection involved 120 respondents residing in the Gambut Subdistrict. Additionally, interviews were conducted with community leaders, organizational representatives, and local government officials. Using a multiple regression approach, the study found that since 2000, 55 new residential complexes have been constructed in the region. The research findings reveal that although economic factors have a minimal impact on environmental conservation variables, fiqh perspectives, and policy variables do affect significantly. These three factors, namely fiqh perspectives, economic factors, and policies collectively exert a significant influence on environmental conservation. Qualitatively, the primary cause of the conversion of paddy fields and peatlands into residential areas is the lack of environmental fiqh literacy. This deficiency has resulted in low awareness of the importance of preserving paddy fields and peatlands as environmental support areas, leaving them vulnerable to encroachment by capital owners eager to develop residential areas. Furthermore, weak oversight by authorities and policymakers has exacerbated this situation.

Spatial Dynamics and Drivers of Urban Growth in Thua Thien Hue Province, Vietnam: Insights for Urban Sustainability in the Global South

Investigating the historical patterns of urban growth and their drivers is crucial to informing sustainable urban planning policies, especially in cities of the Global South. In Vietnam, most studies focus primarily on city extents, offering little insight into urban growth across various provinces. This study, therefore, combined categorical land use and land cover change detection, Random Forest classification and expert interviews to quantify the urban growth between 2000 and 2020, assess urban encroachment upon other land uses, and identify key drivers shaping this growth in Thua Thien Hue province. Findings show that the urban land areas were 27.94 km2, 82.97 km2, and 209.80 km2 in 2000, 2010, and 2020, respectively. Urban encroachment upon other land use types, especially cropland, barren land, rice paddies, shrubs, and forests, was observed in these periods. Additionally, accessibility to built-up areas, DEM, proximity to rice paddies, slope, proximity to street roads, accessibility to social areas, and proximity to cropland are the major spatial drivers of urban growth in the province. The study concludes that rapid urban expansion is evident in the province at the expense of other land use types, especially agricultural land use types, which may impact food security and livelihoods in the province.

Vulnerability and adaptation in flood-prone ecosystems of Bangladesh: a case study of rice farming households

Floods in Bangladesh significantly impact rice production, a vital element of food security. While regional flood effects have been extensively studied, the specific impacts on rice, the country’s primary staple, remain underexplored. This study assesses the effects of floods on rice production, availability, and prices, alongside identifying household vulnerabilities and adaptation strategies. Using both quantitative and qualitative data from secondary sources and interviews with farmers, we analyzed how floods affect rice cultivation and market dynamics. Our findings showed that floods predominantly affect wet season Aman rice, temporarily disrupting cultivation, national yield, and market prices. However, the adoption of stress-resistant varieties and improved agricultural practices has mitigated these effects. While floods have minimal effects on overall rice production, their consequences significantly increase rice prices at the retail level. Importantly, whereas floods prior to 2007 often resulted in substantial rice shortages, the post-2007 era, despite frequent and severe flooding, has witnessed a surplus in rice production. We estimated that despite five flood events in 2020, the country maintained a surplus of 2.9 million tons with minimal reliance on imports. This resilience is attributed to strategic planning, including the diversification of food sources and stockpiling. The government has strengthened the public food distribution system to address immediate food vulnerabilities and encouraged private imports to ensure a stable supply and market prices. Furthermore, government procurement policies are geared towards guaranteeing fair prices for rice farmers. Our findings underscore the importance of integrating these insights into policy frameworks to enhance flood adaptation strategies in Bangladesh.