Arable land polluted by cadmium （Cd） and arsenic （As） is a widespread problem. We applied zero-valent iron （ZVI） and ZVI mixed with limestone （ZVI + LS） as soil amendments， combined with two types of water management strategies， including flooding （F） and alternate wetting and drying （AWD）， to study their immobile ability to prevent Cd and As simultaneously in paddy soil and rice systems. This study lays a theoretical foundation for the reuse of contaminated soils. The dosages of ZVI were set at 1%（ZVI1） and 4%（ZVI4） of the soil mass， while the dosage of LS was 0.3% when mixed with ZVI （ZVI1 + LS and ZVI4 + LS）. The results showed that F management， compared to AWD management， raised soil pH by 0.24-0.85. The immobile effect of F management combined with ZVI4 + LS was the most effective treatment. Specifically， the available fraction （T-EC-Cd） and residual fraction Cd （T-RES-Cd） in the soil decreased by 12.33% and 2.94%， respectively. In contrast， the readily reducible iron and manganese fraction Cd （T-FE-Cd）， organic fraction Cd （T-OM-Cd）， and crystalline iron oxide fraction Cd （T-FEC-Cd） increased by 12.06%， 1.94%， and 1.27%， respectively. The application of ZVI could promote the formation of the amorphous iron oxide fraction of Cd， while LS facilitated the precipitation of CdCO3 and Cd（OH）2 through the speciation changes of Cd in soil colloids and the adsorption mechanisms by amendment. However， the immobile effect of ZVI4 under AWD management was the most effective treatment for As， mainly due to the formation of more Fe-As co-precipitates， such as Fe2As4O9 and FeHAsO4. The changes in rice quality and physiological and biochemical indexes influenced by the amendments were consistent with the trends in soil Cd and As bioavailability. AWD management combined with the ZVI4 + LS treatment significantly reduced the accumulation of Cd and As in rice roots and their translocation to the grains， which were both less than the national safety standards （GB 2762-2022）. The primary pathway for Cd accumulation in the grains changed from root uptake to a combination of root uptake （27.47%） and Cd remobilization from the straw （72.53%）， while As accumulation remained predominantly through straw remobilization.

Alternate wetting and drying (AWD) irrigation improves water use efficiency (WUE) in rice, but its effectiveness in ratoon rice under varying climatic conditions remains unclear. This study is the first 3-year field experiment to assess the climate-dependent impacts of AWD irrigation on ratoon rice, particularly under extreme heat conditions. A 3-year field experiment (2020-2022) was conducted to examine AWD irrigation's effects on soil properties, rice growth, yield, and WUE in a main-season-ratoon rice system. Four irrigation methods were tested: conventional irrigation (CK), AWD during the main-season rice filling period (T1), AWD during the ratoon rice filling period (T2), and AWD during both periods (T3). Weather data showed higher temperatures and lower rainfall in 2022 compared to 2020 and 2021. AWD irrigation increased soil bulk density and total nitrogen, and and NO3- concentrations, while reducing NH4+ concentrations in both rice seasons. In 2020 and 2021, AWD irrigation positively increased root dry weight and activity, net photosynthetic rate, chlorophyll fluorescence, nitrogen metabolism enzyme activity, yield and WUE. However, the opposite was observed in 2022. Specifically, in 2020 and 2021, compared with CK, T1 and T3 increased the yield in the main season by 12.81% and 11.66%; T1, T2 and T3 increased the yield in the ratoon season by 12.93%, 7.66% and 24.10%; T1 and T3 increased the WUE in the main season by 14.90% and 14.07%; and T1, T2 and T3 increased the WUE in the ratoon season by 11.10%, 15.01% and 33.00%, respectively. In 2022, compared with CK, T1 and T3 reduced the yield in the main season by 12.04% and 12.60% and the yield in the ratoon season by 13.72% and 16.37%, and T1 and T3 reduced the WUE in the main season by 10.34% and 10.35% and the WUE in the ratoon season by 3.45% and 10.34%, respectively. AWD irrigation enhances yield and WUE under normal conditions but reduces them under extreme heat. This study highlights the need for adaptive irrigation strategies, integrating heat-tolerance measures to counteract the adverse effects of climate change on ratoon rice production.

HighlightsWhat are the main findings?An IoT-based precision irrigation system integrating soil moisture and water-level sensors with scheduled sensor-based automation effectively controlled AWD irrigation without manual intervention.The IRRI35 treatment maintained high grain yield (7.76 t ha−1) while reducing water use by 28%, energy consumption by 37%, and significantly improving water use efficiency compared to continuous flooding.What are the implications of the main findings?Automated irrigation can overcome key adoption barriers of AWD by minimizing labor requirements and improving water governance.Large-scale implementation could reduce irrigation energy demand, and enhance sustainability in rice production systems.Despite its significant water-saving potential, the adoption of alternate wetting and drying (AWD) irrigation remains limited due to infrastructure constraints and intensive manual monitoring requirements. An automated precision irrigation system was developed and tested at the Bangladesh Rice Research Institute research farm in Gazipur, Bangladesh. The system combined ultrasonic water-level sensors, capacitive soil moisture sensors, an Arduino-based microcontroller, a GSM communication module, and solar-powered automatic control gates. Field performance was evaluated following a Randomized Complete Block Design (RCBD) under four irrigation treatments: IRRISAT, IRRI35, IRRI25, and continuous flooding (CF). The first three irrigation treatments were operated using scheduled daily decision windows, in which irrigation actions were automatically triggered based on predefined schedules and sensor threshold values. In IRRISAT, irrigation started when soil moisture dropped slightly below saturation and stopped at a ponding depth of 5 cm, while IRRI35 and IRRI25 were triggered at volumetric soil water contents of 35% and 25%, respectively, with the same upper cutoff of 5 cm ponding depth; CF served as the control. The IRRI35 treatment achieved a high grain yield (7.76 t ha−1) while reducing water use by 28% and energy consumption by 37% compared to CF. Water use efficiency was considerably higher under IRRI35 (9.4 kg ha−1 mm−1) than under CF (6.7 kg ha−1 mm−1). The automated system proved to be reliable and precise in scheduled irrigation control, significantly reducing water use and labor requirements. The findings suggest that large-scale adoption of the system under real-world cultivation conditions could reduce irrigation energy needs and contribute to sustainable water governance in rice production.

The agricultural sector in Bangladesh is a significant contributor to greenhouse gas (GHG) emissions, driven by intensive crop production, irrigation-dependent groundwater extraction, and associated energy use. At the same time, high-input agriculture remains essential for food security and economic growth, creating a critical sustainability challenge. This study provides an integrated overview linking Bangladesh’s economic context, agri-food land use, and groundwater management to GHG emissions. Based on a synthesis of peer-reviewed literature, national statistics, and international datasets, the review examined how dry-season irrigation—largely dependent on diesel and electricity-powered groundwater pumping—drives energy demand and emissions. The analysis highlights the influence of climatic variability and geographic conditions on emission patterns, with methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) identified as the dominant gases from agricultural activities. The review further evaluates mitigation options, including alternate wetting and drying (AWD), surface water use, solar irrigation, prilled urea utilization (PU), urea deep placement (UDP), integrated plant nutrient system (IPNS), and anaerobic digestion. Existing policy frameworks and groundwater management practices are also assessed. The findings underscore the need to better integrate groundwater management with low-carbon agricultural practices to reduce emissions while sustaining productivity under climate change in Bangladesh.

This study assesses the economic efficiency (EE) of low-emission rice production under Alternate Wetting and Drying (AWD) irrigation in the Mekong Delta using survey data from 250 households. Descriptive statistics profile farm characteristics, practices, and costs; efficiency is estimated with non-parametric Data Envelopment Analysis (DEA), and determinants are examined via Ordinary Least Squares. Farmers adopting AWD achieved an average profit of 26.30 million VND per hectare per crop, with average costs of 21.80 million VND and an average yield of 7.14 tons/ha/crop. The cost structure is dominated by fuel and energy, fertilizer, and hired labor. Reported fertilizer use averaged 100.62 kg/ha of nitrogen, 47.84 kg/ha of phosphorus, and 53.37 kg/ha of potassium per crop—broadly consistent with prior Mekong Delta figures (e.g., N ≈ 99.6, P ≈ 46.69, K ≈ 51.8 kg/ha/crop), with phosphorus application marginally lower in some comparisons. The DEA results indicate an average EE of 48.45%, alongside technical and allocative efficiency of 69.94% and 70.44%, respectively. The regression shows that education and cultivated area are significant positive correlates of efficiency, whereas age, gender, household labor, and farming experience are not statistically significant. Overall, while AWD rice farming delivers measurable outcomes on yields and costs, average EE remains below optimal, highlighting the importance of scale and human capital for performance gains.

Biofortified rice has emerged as one of the most promising strategies to enhance the micronutrient content of staple crops, offering a practical pathway to reduce stunting and improve nutritional security. In response to the challenges posed by climate change, water scarcity, and the need for more efficient production systems, this study examined the effects of water- and crop- management technologies on the physiological performance and yield of biofortified rice. A factorial randomized complete block design compared continuous flooding and alternate wetting and drying (AWD) irrigation with two crop management systems: conventional and a new technology. The AWD system enhanced photosynthesis without significantly affecting transpiration or stomatal conductance, indicating improved carbon assimilation and more efficient water use. Both AWD and the new technology individually increased dry grain yield per clump, while their combination produced heavier grains, higher productivity, greater 1000-grain weight, and improved water-use efficiency compared with other treatments. Although yield differences were not statistically significant, the consistent upward trends indicate synergistic potential when nutrient management is optimized. Overall, integrating AWD irrigation with new technology crop management can enhance resource efficiency in biofortified rice cultivation while maintaining yield stability under water- limited conditions.

Abstract Rice is cultivated on approximately 1,000,000 ha in the Mediterranean area, with production concentrated in Egypt, Italy, Türkiye, Spain, Grece and Portugal. In these areas, rice is traditionally established by wet seeding and cultivated under continuous flooding (WFL), which requires larger volumes of water compared to other irrigation practices. The aim of this study is to benchmark irrigation methods alternative to WFL across sites representative of the rice agro-ecosystems producing areas of 5 of the main rice-producing countries. For each site, WFL and one or more alternative methods, selected and adapted to site-specific conditions, were implemented and monitored for at least two years. The alternative methods included: alternate wetting and drying (AWD), dry seeding and delayed flooding (DFL), water input/output reduction (WIR), hybrid irrigation (HYBRID), sprinkler irrigation (SPRINKLER), surface drip irrigation (DRIP), and subsurface drip irrigation (SDI). The results suggest that AWD, DFL and WIR, which are easy-to-implement flooding techniques, increase water productivity (WP) and preserve yield production. Both SPRINKLER and HYBRID showed a higher increase in WP (by about 50%) while maintaining or even increasing yield production, but at the cost of changes in irrigation management and investments for equipment purchases (limited in the case of HYBRID and greater for SPRINKLER). DRIP and SDI increasing WP by more than 100% but, sometimes, yield was significantly reduced. Additionally, pressurized irrigation methods, and especially DRIP and SDI, showed the need for careful consideration of site conditions (during system design and management) to avoid yield losses.

The sustainability of rice production in traditional ways under intensive puddled condition is increasingly threatened due to fresh water scarcity and soil degradation by intensive puddling in many areas. Repeatedly imposing wetting and drying cycle and conservation tillage can improve soil physical environment and root growth. This study investigated the combined impacts of alternate wetting and drying (AWD) irrigation and reduced tillage on the physico-chemical properties, root growth dynamics and yield of rice. A field experiment was conducted with two water regimes- continuously flooded (CF) and AWD; and three tillage intensities- conventional, reduced and zero tillage. A rice variety BRRI Dhan 87 was grown. Different root parameters and yield parameters were measured. Soil physical changes and nutrient availability were determined. The root length (20%), root dry mass (70%) and yield (20%) were significantly greater in reduced tillage compared to zero tillage. However, there was no yield difference in conventional and reduced tillage. The penetration resistance of soil was not differed between AWD and CF treatment with similar yield. The nitrogen content in soil (0.30%) and plant (2.93%) was greater in AWD fields with reduced tillage than CF system. The results of this study suggested that combination of AWD and reduced tillage improved soil structure and nutrient availability which positively influenced yield of rice.

The systematic acquisition of field data is a major bottleneck for identifying scalable solutions that effectively reduce emissions while maintaining productivity in agricultural systems such as rice. This 2 nd volume of a multilayered presentation of Greenhouse Gas (GHG) emission measurements in rice fields links up with a review of scientific findings achieved with well-established measurement approaches. Special emphasis is given to advanced systems with laser-based trace gas analyzers (TGA) integrated into an upgraded closed chamber system. A synchronized field experiment was conducted under Alternate Wetting and Drying (AWD) and Continuous Flooding (CF), comparing a) manual sampling with gas chromatography representing a time-tested reference method, b) a TGA in a stand-alone (portable) configuration, and c) a TGA assembled with a semi-automated multi-valve system. Following a preparatory test resulting in an optimum sampling interval of 4 min, the reliability of the TGA measurements was assessed by calculating R² from linear regression of gas concentration versus sampling time. Based on a paired t-test, the three approaches did not present any significant difference except for rare outliers with p ≤ 0.01 reaching a maximum difference of 12.62 mg m - ² d - ¹. In total, these disparities were small compared to overall emission levels and occurred randomly across treatments, indicating that there was no systematic bias between approaches. In the second part of this volume, we broadened the perspective to a comparative assessment of methods supplemented by projecting future developments in GHG measurements in rice. Both portable and multi-valve TGA systems provide greater efficiency and real-time data acquisition while their mutual comparison is a function of research objectives and project settings. Regarding technical features of future measurement systems in rice, we highlighted the multi-valve TGA system as a feasible core component of a high-throughput screening platform intended to identify low-emission rice varieties for immediate dissemination across scales and integration into breeding programs. Finally, we assessed the possible synergies of these high-frequency TGA data sets with other emerging technologies, namely Remote Sensing and Machine Learning, under a diversified regulatory framework for GHG accounting that will likely dissolve the distinction of Tier 2 and 3 approaches for rice production.

Climate change and declining water resources adversely affect rice production. Conventional continuous flooding in rice cultivation requires high water input, posing challenges under water scarcity and contributing to greenhouse gas (GHG) emissions. Alternate wetting and drying (AWD) is a water‐saving irrigation method that addresses water limitations in flooded cultivation. A Scopus literature search resulted in 1,830 articles, of which 77 were selected for quantitative analysis based on inclusion and exclusion criteria. The critical review revealed that AWD reduces water input, increases water productivity and use efficiency. Physiological adjustments include enhanced indole acetic acid, abscisic acid, and cytokinin regulation, and increased enzymatic activities of sucrose and starch synthases. These changes improve root architecture and gas exchange traits, and facilitate efficient assimilate partitioning to maintain stable grain yield. AWD mitigates GHG emissions, reduces pests and disease incidences. Integration of organic amendments enhances soil health and moisture retention capacity. However, widespread adoption is hindered by weed infestations, sociocultural resistance, and economic risk perceptions. Research gaps include limited integration of weed and nutrient management, uncertain AWD performance under extreme weather events, and yield variations due to agroecological conditions. Addressing these through targeted research, local agricultural policies and farmer‐centric strategies is key to promoting AWD for sustainable rice cultivation.

Climate change and diminishing water resources are concomitant threats to sustainable rice production. Alternate wetting and drying (AWD), a water-saving irrigation practice, reduces water requirements for rice (Oryza sativa L.) cultivation. However, the effects of AWD on grain yields are variable. Therefore, the study evaluated the impacts of AWD on root traits, canopy microclimate, anthesis timing, hormonal regulation and grain yield in rice varieties, “IR 64”, “Anna (R) 4”, “CO 53”, and “TKM 15”. AWD was imposed 14 days after transplanting and underwent 14 drying–wetting cycles. Total root length, volume, and surface area increased with AWD, while root diameter decreased compared to continuous flooding (CF), particularly in “Anna (R) 4” and “TKM 15”. This indicates improved root plasticity and water uptake to maintain cooler canopies. As a result, anthesis timing was advanced by 30–40 min. “Anna (R) 4” had the earliest flower opening, thereby reducing spikelet sterility by shifting flowering to cooler morning hours. Hormonal profiles revealed that IBA enhanced root development and elevated MeJA contributed to early anthesis in “Anna (R) 4”. tZR in “Anna (R) 4” was maintained at comparable levels to CF, facilitating grain filling in AWD. Spikelet sterility, chalkiness, grain yield and total dry matter production were decreased in AWD across all varieties. However, “Anna (R) 4” maintained the lowest yield reduction and superior grain quality due to lower sterility and chalkiness. The study identified “Anna (R) 4” as an adaptive variety with key traits of root plasticity, early anthesis, reduced sterility and chalkiness for yield protection.

Rice cultivation is a major contributor to agricultural nitrous oxide (N2O) emissions, a greenhouse gas with a global warming potential approximately 300 times greater than carbon dioxide (CO2) and an atmospheric lifetime of ~121 years. Although water-saving irrigation practices, including Alternate Wetting and Drying (AWD) and Mid-Season Drainage (MD), effectively reduce methane (CH4) emissions by up to 27.6% and decrease irrigation water use by 15–30%, they often intensify soil aeration and stimulate microbial nitrification-denitrification, leading to substantial increases in N2O emissions. Reported increases range from 28.8% to more than 16-fold, with specific studies showing rises from 0.02 to 0.51 kg N2O-N ha−1 under AWD and up to 242% under MD. These trade-offs threaten the long-term sustainability of water-saving rice systems. Iron-based soil amendments (IA) have emerged as a promising mitigation strategy to counteract these elevated N2O emissions. For instance, iron (Fe) powder enhances the activity of Fe-reducing bacteria, such as Geobacter and Anaeromyxobacter, generating Fe2+ and lowering the soil's redox potential, which promotes the complete reduction of N2O to N2. Furthermore, other Fe amendments, including Fe-modified biochar and soluble ferrous iron (Fe2+), help mitigate N2O emissions by immobilizing NH4+, reducing the populations of ammonia-oxidizing bacteria, and supplying surplus electrons that enable denitrifiers to fully reduce N2O to N2. Empirical studies show that Fe-based amendments can reduce N₂O emissions by ~40% (iron-slag silicate fertilizer) and lower nitrification rates from 9.38 to 5.43 μg N g−1 d−1 when applied as Fe-modified biochar. Iron powder also enhances atmospheric N fixation, reducing reliance on synthetic nitrogen fertilizers. Integrating IA with AWD and/or MD, therefore, offers a synergistic pathway to sustain the benefits of water-saving irrigation while minimizing unintended increases in N2O emissions. Field-scale, multi-season studies are still needed to validate long-term impacts and assess residual Fe behavior, but current evidence demonstrates strong potential for these combined strategies to support climate-resilient, low-emission rice production aligned with global mitigation goals.

Agricultural methane (CH₄) emissions remain a critical yet under-addressed component of global climate mitigation, particularly in tropical economies. This study investigates the long- and short-run drivers of CH₄ emissions from Indonesia’s agricultural sector between 1970 and 2022, focusing on three major sources: rice cultivation, enteric fermentation, and manure management. Using a dynamic econometric framework—including Autoregressive Distributed Lag (ARDL), Dynamic Ordinary Least Squares (DOLS), and Newey–West estimators—we quantify source-specific impacts and evaluate structural changes following post-2008 climate policy reforms. Results confirm rice cultivation as the dominant long-run contributor, where a 1% increase in CH₄ from paddy fields corresponds to a 0.72% rise in total agricultural methane emissions. Enteric fermentation and manure management also show significant effects, though to a lesser extent. A post-2008 policy dummy indicates a structural shift in emission dynamics, reflecting Indonesia’s transition toward climate-aligned agriculture through REDD+ and the National Action Plan for GHG Reduction (RAN-GRK). Short-run dynamics reveal corrective adjustments after emission shocks, highlighting system responsiveness to policy and environmental changes. The study underscores both the potential and the limitations of national mitigation efforts in reshaping long-term emission trends. Findings suggest that methane mitigation strategies—such as alternate wetting and drying (AWD) in rice farming and improved feed quality for livestock—can reduce emissions without compromising productivity. This study offers novel empirical insights for policymakers and climate practitioners seeking to integrate food security, sustainability, and low-emission agricultural development in emerging economies.

Arsenic (As) accumulation in rice (Oryza sativa L.) is considered a major environmental and food safety concern, particularly in flooded agroecosystems where reducing conditions mobilize As from soils. Portugal is one of Europe’s rice producers, especially in the Tejo, Almansor, and Sorraia valleys. As such, this study evaluates As pathways across 5000 ha of rice fields in the Tagus, Sorraia, and Almansor alluvial plains by combining soil, water, and plant analyses with a geostatistical approach. The soils exhibited consistently elevated As concentrations (mean of 18.9 mg/kg), exceeding national reference values for agricultural soils (11 mg/kg) and forming a marked east–west gradient with the highest levels in the Tagus alluvium. Geochemical analysis showed that As is strongly correlated with Fe (r = 0.686), indicating an influence of Fe-oxyhydroxides under oxidizing conditions. The irrigation waters showed low As (mean of 2.84 μg/L for surface water and 3.51 μg/L for groundwater) and predominantly low sodicity facies, suggesting that irrigation water is not the main contamination vector. In rice plants, As accumulation follows the characteristic organ hierarchy roots > stems/leaves > grains, with root concentrations reaching up to 518 mg/kg and accumulating progressively in the maturity phase. Arsenic content in harvested rice grains was 266 μg/kg (with a maximum of 413.9 μg/kg), being close to EU maximum limits when considering typical inorganic As proportions, assuming 60 to 90% inorganic fraction. Together, the findings highlight that a combined approach is essential, and identify soil geochemistry (and not irrigation water) as the primary source of As transfer in those agroecosystems, due to the flooded conditions that trigger the reductive dissolution of Fe oxides, releasing As. Additionally, the results also identified the need for targeted monitoring in areas of elevated As content in soils and support future mitigation through As speciation analysis, cultivar selection, improved fertilization strategies, and water-management practices such as Alternate Wetting and Drying (AWD), to ensure the long-term food safety.

Methane emissions from rice paddies account for over 11% of global atmospheric CH4, making water management practices such as Alternate Wetting and Drying (AWD) critical for climate change mitigation. Remote sensing offers an objective approach to monitoring AWD implementation and improving greenhouse gas estimation accuracy. This study investigates the backscattering mechanisms of L-band SAR for inundation/non-inundation classification in paddy fields using full-polarimetric ALOS-2 PALSAR-2 data. Field surveys and satellite observations were conducted in Ryugasaki (Ibaraki) and Sekikawa (Niigata), Japan, collecting 1360 ground samples during the 2024 growing season. Freeman–Durden decomposition was applied, and relationships with plant height and water level were analyzed. The results indicate that plant height strongly influences backscatter, with backscattering contributions from the surface decreasing beyond 70 cm, reducing classification accuracy. Random forest models can classify inundated and non-inundated fields with up to 88% accuracy when plant height is below 70 cm. However, when using this method, it is necessary to know the plant height. Volume scattering proved robust to incidence angle and observation direction, suggesting its potential for phenological monitoring. These findings highlight the effectiveness of L-band SAR for water management monitoring and the need for integrating crop height estimation and regional adaptation to enhance classification performance.

Hierarchical ROS network regulating rice root iron plaque formation, Fe speciation, mineral crystallinity, and absorption of nutrient elements has been revealed. The root iron plaque (RIP) of rice plays a critical role in heavy metal adsorption and rhizosphere environment regulation. However, the regulatory mechanisms of reactive oxygen species (ROS) in RIP formation remain poorly understood. This study investigated hydroponically cultivated rice under Fe(II) concentration gradients (50-200mg L-1) and water management regimes [contrast of continuous waterlogging (CW) with alternate wetting and drying (AWD)]. Using ROS scavengers [Cu(II), DMTU, TBA] to specifically inhibit O2·-, H2O2, and ·OH generation, we systematically elucidated ROS-mediated regulation of RIP formation, Fe redox speciation, and mineralogical structure. Key findings include: (i) ROS scavenging experiments revealed O2·- as the dominant contributor to RIP formation (17.55 ± 0.89% reduction after scavenging), followed by H2O2 (11.86 ± 0.45%) and ·OH (6.35 ± 0.34%); (ii) O2·- depletion reduced Fe(III)/Fe(II) ratios from 4:1 to 1:1, suppressed crystalline mineral formation (e.g., hematite), and increased weakly crystalline siderite proportions; (iii) XPS and XRD analyses demonstrated that ROS drive Fe(II) oxidation and mineral phase transitions by oxidative chain reactions (O2·- → H2O2 → ·OH), with O2·- being pivotal for maintaining high oxidation states and crystallinity in RIP. (iv) The mineral crystallinity of RIP affects its regulatory effect on nutrient elements. Scavenging O2·- treatment results in low crystallinity of RIP, which weakens its adsorption and fixation capacity for trace elements, such as Mn, Zn, and Cu. Consequently, the contents of Mn, Zn, and Cu in the iron plaque are low, while their contents in rice plants are high. This study unveils a hierarchical ROS regulatory network governing RIP formation, providing theoretical foundations for optimizing RIP functionality through water management strategies.

Abstract Water scarcity is a growing challenge for sustainable agriculture, particularly in water-intensive crops like rice. This study evaluates the impacts of three irrigation methods; drip irrigation (D), alternate wetting and drying (AWD), and continuous flooding (CF) on rice yield, water productivity, and economic returns over three years. Two irrigation levels (I1: Application of water equal to 25% of the water between the saturation point and field capacity when the soil moisture was near field capacity, I2: Application of water to field capacity when 25% of the available water holding capacity was depleted) were applied. Results revealed that irrigation methods and levels significantly influenced rice yield at the 1% level. The highest average yield (7.95 t/ha) was obtained from CF, followed by AWDI1 (7.60 t/ha) and DI1 (6.39 t/ha). Drip irrigation and AWD reduced water use by 30–57% compared to CF but resulted in yield losses of 2–52%. However, the AWDI1 treatment recorded the highest water productivity and net income (US$2455 ha), outperforming CF and DI1. Economic analyses confirmed the viability of AWD and drip irrigation as sustainable alternatives to CF, balancing water conservation with profitability. These methods are particularly effective in regions with limited water availability, offering a sustainable approach to rice cultivation without significant trade-offs in yield quality. This study also underscores the importance of integrating physical and economic indicators when selecting irrigation strategies to ensure food security and resource sustainability in the face of water scarcity.

Capacity building in agri-food innovations is increasingly recognized as a critical pathway to address the dual challenges of ecological sustainability and livelihood enhancement. This study was undertaken using a structured framework to strengthen socio-ecological growth through targeted objectives. The key objectives included developing the technical and entrepreneurial competencies of tribal farm women for adopting climate-smart, nutrient-smart, and water-smart practices; institutionalizing community-based platforms such as farmer producer organizations to foster participatory learning and collective action; integrating digital tools and ICT-based solutions into extension processes; and promoting resilience and awareness of socio-ecological linkages by incorporating modules on climate adaptation, biodiversity conservation, and nutrition-sensitive farming. The study was conducted in selected villages of Nalgonda district, Telangana, India with a sample size of 110 tribal farm women. Interventions introduced were Good Agricultural Practices, reduced seed rate, line sowing of paddy, water management through Alternate Wetting and Drying (AWD), weed management through judicious use of herbicides, adoption of climate-resilient and high-zinc rice varieties, and provision of sprayers to tribal farm women for custom hiring enterprises. Results showed that adoption of GAPs improved paddy yield while herbicide application reduced labor costs. The establishment of custom hiring services further enhanced income opportunities for women farmers. The integrated capacity-building approach not only improved productivity and reduced input costs but also strengthened livelihood security and ecological resilience among tribal farm women. These findings highlight the potential of targeted agri-food innovations to accelerate sustainable agricultural transformations and promote inclusive socio-ecological development. Moreover, the demonstrated success underscores the need for scalable models supported by an enabling policy framework, which can facilitate wider replication and sustained impact across similar agro-ecological and socio-economic contexts.

ABSTRACT Alternate wetting and drying (AWD) irrigation alleviates prolonged flooding‐induced soil redox potential decline and methane emissions in rice paddies. AWD typically maintains a 15 cm water table depth. While straw incorporation intensifies soil reduction under prolonged flooding, the optimal intensity of AWD under straw incorporation remains unclear. We conducted a field experiment in northeast China comparing two AWD regimes (AWD15 and AWD20, draining to 15/20 cm depth) with straw incorporation. Soil reductive substance content, root activity, tillering dynamics and yield were systematically monitored. The results demonstrated that compared with AWD15, the AWD20 treatment significantly reduced the content of soil reductive substances, with a 22.6% and 42.7% decrease in soil Fe 2+ and Mn 2+ content, respectively, and an 80.9% and 82.7% decrease in total reductive matter content and active reductive matter content, respectively, at mid‐season drainage. The soil Fe 2+ content was negatively correlated with the redox potential of the soil. After rewetting, AWD20 treatment significantly increased soil microbial biomass carbon (MBC) and nitrogen (MBN) content. Compared with the AWD15 treatment, only the number of tillers decreased by 4.8% in the AWD20 treatment, while there was no statistical difference in rice root activity, effective spike number, carbon and nitrogen content of rice, nitrogen fertiliser partial factor productivity (PFP), harvest index, yield and yield stability. The findings suggest that AWD20 holds promise as a sustainable irrigation strategy for straw‐incorporated rice systems, contributing to improved plant growth conditions and enhanced field sustainability.

Redox-mediated Fe-P coupling modulates phosphorus releasing in paddy soils: Hydrological controls under water-saving irrigation.