Field Drainage Research Articles

High drain field impact ionization transistors as ideal switches

Impact ionization effect has been demonstrated in transistors to enable sub-60 mV dec−1 subthreshold swing. However, traditionally, impact ionization in silicon devices requires a high operation voltage due to limited electrical field near the device drain, contradicting the low energy operation purpose. Here, we report a vertical subthreshold swing device composed of a graphene/silicon heterojunction drain and a silicon channel. This structure creates a low voltage avalanche impact ionization phenomenon and leads to steep switching of the silicon-based device. Experimental measurements reveal a small average subthreshold swing of 16 µV dec−1 over 6 decades of drain current and nearly hysteresis-free, and the operating voltage at which a vertical subthreshold swing occurs can be as low as 0.4 V at room temperature. Furthermore, a complementary silicon-based logic inverter is experimentally demonstrated to reach a voltage gain of 311 at a supply voltage of 2 V.

Effects of Fallow Season Water and Straw Management on Methane Emissions and Associated Microorganisms

The effects of fallow season water and straw management on methane (CH4) emissions during the fallow season and the subsequent rice-growing season are rarely reported, and the underlying microbial mechanisms remain unclear. A field experiment was conducted with four treatments: (1) fields flooded in both the fallow and rice seasons (FF), (2) fields drained in the fallow season and flooded in the rice season (DF), (3) FF with straw retention (FFS), and (4) DF with straw retention (DFS). The CH4 emissions in fields under different water and straw treatments were monitored using the static closed chamber method. Methanogenic and methanotrophic communities in these fields were examined using terminal restriction fragment length polymorphism (T-RFLP) analysis based on the mcrA gene and pmoA gene encoding methyl coenzyme M reductase and particulate methane monooxygenase, respectively. The results showed that CH4 emissions were significantly affected by water management, straw retention, season, and their interactions. Over 80% of CH4 emissions occurred during the rice season. Field drainage during the fallow season reduced CH4 emissions by 47.0% and 53.8% with and without straw during the rice season, respectively. Water management altered the abundance and composition of methanogens and methanotrophs, whereas the effects of straw retention were less pronounced. The quantitative polymerase chain reaction (qPCR) assay revealed that field drainage in the fallow season decreased the mcrA gene abundance by 30.0% and 23.2% with and without straw in rice season, respectively, and increased the pmoA gene abundance by 108.9% and 213.7% with and without straw in rice season, respectively. CH4 flux was significantly positively associated with mcrA gene copy number and the ratio of mcrA to pmoA gene copy number, whereas it was significantly negatively correlated with the pmoA gene copy number. Results indicated that fallow drainage greatly decreased CH4 emission not only during the fallow season but also during the subsequent rice season by altering the community composition of methanogens and methanotrophs. These findings provide scientific insight into the role of water and straw management in controlling CH4 emissions through microbial community dynamics.

Simulation of edge water invasion mitigation of the SAGD chamber by low temperature oxidation (LTO) coking air injection and optimization of operating parameters

During the long-term use of steam assisted gravity drainage (SAGD) in oil fields, the continuous expansion of the steam chamber often leads to edge water invasion, which significantly reduces thermal efficiency and oil production rate. To address this challenge, we hypothesize that a low temperature oxidation (LTO) coke formation air injection method may alleviate edge water invasion. To test our hypothesis, we developed a numerical SAGD model tailored to a typical SAGD field, the Guantao Du84 block in the Liaohe Oilfield, China. The model incorporates a four-step coke generation kinetics and considers the complexity of coke distribution. Our results reveal that coke generation (1) shifts the direction of edge water flow from the steam chamber to a vertical downward direction, (2) causes pore clogging, resulting in reduced flow velocity, (3) leads to reduced porosity and water cut, significantly improving oil recovery as compared to nitrogen injection (e.g., by 18.2% in the Guantao Du84 block), and (4) allows for proactive establishment of coke zones before the water cut reaches 85%. Through this numerical study, we investigate the feasibility of implementing the method of LTO coking air injection in SAGD fields and provide insights into its optimization.

Effects of depressions and drainage systems on soybean (Glycine max (L.) Merill) growth during the early growth stages under excess water stress conditions

ABSTRACT Soybean (Glycine max (L.) Merill) productivity is severely compromised under conditions of excess water, particularly during the early growth stages. Depressions in converted paddy fields are believed to significantly contribute to excess water stress. Farmers typically use drainage systems, such as field ditches and pipe drains to improve field drainage. In this study, we aimed to evaluate the impacts of depressions and drainage systems on soybean growth during the early growth stages in farming fields. Using uncrewed aerial vehicles and imaging processing software, we observed the soybean coverage ratio at two and four weeks after sowing. We analyzed the relationship between the coverage ratio and depression depth, distance from field ditches, and distance from pipe drains. Depressions deeper than 2 cm were present in all study fields, and the coverage ratio increase from 2 to 4 weeks after sowing was negatively correlated with depression depth. Although the distance from pipe drains was negatively related to the coverage ratio increase, the distance from field ditches had a limited effect. The construction of pipe drains significantly improved the coverage ratio increase, particularly in areas with deep depressions and near pipe drains, by up to 23.0 times in this study. Therefore, constructing pipe drains near depressions is an effective way to mitigate the impact of depressions and excess water stress on soybean growth during the early stages. Our results will be useful for developing strategies to improve drainage and soybean growth during early growth stages.

Design and implementation of tilting‐plate drainage equipment for paddy field

AbstractDrainage equipment is an important part of paddy field drainage and irrigation system, and its performance research and application are conducive to the promotion and implementation of high‐standard farmland construction. Aiming at the different water demand of rice in different growing stages, low water level control precision, large manual operation and extensive management of existing drainage machinery, a tilting‐plate drainage equipment using upper overflow mode was proposed in this paper. Based on the Geneva mechanism principle, a unique linkage mechanism is designed, which can realize water retaining operation and silt discharge operation through a single motor drive, and the relationship between the motor angle and the water retaining height is established. Through mechanical analysis and dynamic simulation of the mechanism, the motion characteristics of the water baffle, silt plate and the change of the motor torque are studied. A remote control system based on a 4G module is designed to control the drainage equipment easily through the user layer. The performance test of the prototype shows that the precision error of the optimized water retaining height control is less than 3.75%. The maximum height of water retaining operation is 180 mm, and the maximum load of silt discharge operation is 10 kg, which can meet the actual operation requirements. The design is beneficial to improve the precision and intelligence level of paddy field drainage management, and the research process can provide some help for the development and application of this kind of equipment.

Gate mesa terminal with drain-field-plated β-Ga2O3 MOSFET with ultra-high power figure of merit

In this article, a novel gate mesa terminal (GMT) device structure incorporating a drain field plate is proposed. This design features mesa terminals with varying bevel angles positioned atop the gate. The objective is to enhance the breakdown voltage (Vbr) and reduce the on-resistance (Ron) of the lateral β-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET). Through the implementation of the GMT structure, the peak electric field within the β-Ga2O3 MOSFET is redirected towards the passivation layer. This effectively mitigates the electric field in the epitaxial layer, thereby increasing Vbr. The optimal values for Vbr, specific on-resistance (Ron,sp) and maximum transconductance (gm) across various GMT structures are 4827 V, 9.9 mΩ·cm2 and 15.32 mS/mm, respectively. These metrics represent a 2.63-fold, 0.88-fold, and 1.25-fold improvement compared to the non-GMT structure. Additionally, when the doping concentration of epitaxial layer is 1 × 1016 cm−3, the GMT achieves an enhanced threshold voltage of +0.26 V. By simulating different bevel angles, field plate parameters, epitaxial layer doping concentrations, and mesa thicknesses, an optimal power figure of merit (PFOM) of 1.914 GW cm−2 is attained. This innovative design introduces a fresh concept for the development of the next generation of high voltage and high-power devices rated above 4 KV.

Centrifuge modeling-of-models investigation on earthquake-induced excess pore pressure behavior of silty sand

Two centrifuge experiments conducted at Rensselaer Polytechnic Institute (RPI) aimed to evaluate the effectiveness of the used centrifuge scaling laws and validate results obtained within the project, related to the liquefaction behavior of silty sand soils under simulated field drainage conditions. These experiments, replicating a 5-m thick silty sand layer under 1 atm overburden pressure and featuring a double drainage condition, were performed at two different centrifugal accelerations. Due to the difficulties encountered in saturating silty sand, this paper presents a bottom-up saturation method, verified through assessments of remaining air volume after saturation. Despite differing g-levels, the tests consistently demonstrated similar behaviors in terms of acceleration, pore pressure buildup and dissipation, and stress-strain responses, validating the saturation and modeling technique for silty sand.

Application of morphotectonic indices for assessing active tectonics: A case study of Acheron river basin

Rivers tend to alter the morphology of their bed and valley as a response to changes in their base level. The study of a drainage basin's tectonic activeness is very important. But especially in areas where rates of vertical tectonic movements are scarce, the morphometric analysis can be proved to be a very accurate method for assessing the effects of neotectonic movements on a drainage network. This method is easy to apply, as it does not require a lot of data. This study concerns the drainage basin of Acheron river in Epirus, Greece. In order to assess of river's response to active tectonic movements, a morphometric analysis was conducted, using a digital elevation model (DEM). Seven morphometric parametres and five geomorphic indices were calculated for the entire basin, as well as 9 sub-basins. Subsequently, each sub-basin was categorised into three categories regarding tectonic activeness (high-medium-low) for each index individually. The relative active tectonics index was also calculated, as the average of the aforementioned morphometric parametres and geomorphic indices. Based on that, each sub-basin was categorised into three categories regarding the overall tectonic activeness (low-medium-high). These results were compared with the drainage pattern and field observations, so as to gain insights on the tectonic activeness of the sub-basins and the entire basin of Acheron.

18 A/1020 V p-GaN-gated HEMTs with Isosceles Trapezoidal-Shaped Multi-Finger Structure

In this article, we investigate the effects of gate and drain field plates and isosceles trapezoidal-shaped multi-finger structures on the characteristics of high current p-GaN-gated high-electron-mobility transistors (HEMTs). By optimizing the lengths of gate and drain field plates, the p-GaN-gated HEMTs with 200 μm have a breakdown voltage of 1893 V, a specific on-resistance of 7.0 mΩ-cm2, and a Baliga figure of merit (BFOM) value of 511 MW cm−2. Using the optimized isosceles trapezoidal-shaped multi-finger metallization on the source and drain, the p-GaN-gated HEMT with a 100 mm gate width can reach a current of 2.3 A. Combining all the optimum parameters of field plates and isosceles trapezoidal-shaped multi-finger, the fabricated 600 mm p-GaN-gated HEMT exhibits an output current of 18 A, an on-resistance of 0.7 Ω, and a breakdown voltage of 1020 V. Furthermore, the device also exhibits good thermal stability at high temperatures. These results demonstrate the potential and advantages of p-GaN-gated HEMT for power applications.

Improved high voltage operation of amorphous In–Ga–Zn–O thin film transistor by carrier density enhancement

We report on improved high voltage operation of amorphous-In–Ga–Zn–O (a-IGZO) thin film transistors (TFTs) by increasing carrier density and distributing the high bias field over the length of the device which utilizes an off-set drain structure. By decreasing the O2 partial pressure during sputter deposition of IGZO, the channel carrier density of the high voltage a-IGZO TFT (HiVIT) was increased to ∼1018 cm−3. Which reduced channel resistance and therefore the voltage drop in the ungated offset region during the on-state. To further decrease the electric field in the offset region, we applied Ta capping and subsequent oxidation to locally increase the oxygen vacancy levels in the offset region thereby increasing local carrier density. The reduction of the drain field in the offset region from 1.90 V μm−1 to 1.46 V μm−1 at 200 V drain voltage, significantly improved the operational stability of the device by reducing high field degradation. At an extreme drain voltage of 500 V, the device showed an off-state current of ∼10−11 A and on-state current of ∼1.59 mA demonstrating that with further enhancements the HiVIT may be applicable to thin-film form, low leakage, high voltage control applications.

Novel double deck gate field plate structure on a normally-off AlGaN/GaN HEMT- An extensive analysis

A novel double deck gate field plate structure on a normally-off AlGaN/GaN HEMT is proposed and compared with the conventional no field plate structure. Several passivation materials with relative permittivity (εr) ranging from 3.9 to 22 is taken into consideration to study the breakdown and DC characteristics. The implementation of field plate along with a higher εr material helps in improving breakdown voltage (VBr) as they both decrease the electric field at the gate's drain edge. Aiming device optimization several field plate configurations are studied including tri field plate structure, dual field plate structures and single gate FP structure. Extensive analysis in these structures are done with different lengths of the field plates and distance between source and drain. Distance between source and drain (LSD) is varied from 8.4 to 13.4 μm, source FP lengths (LS_FP) varies from 1 to 7 μm, gate FP lengths (LG_FP) varies from 0.9 to 2.3 μm and drain FP lengths (LD_FP) varies from 0.2 to 4.9 μm. In all scenarios with varying LSD, VBr rises with increasing LSD. For source, gate and drain FP lengths variation, VBr decreases as it gets longer because the electric field becomes very high. As the distance between the FP edge and the drain becomes narrower with increase in FP lengths, the breakdown occurs at lower voltage. At LSD 13.4 μm, this novel double deck gate FP structure with conventional drain field plate structure gives highest VBr of 1660 V and a small Ron of 2.39 Ω mm as compared to other structures. It also outperforms the other three structures in FT (9.84 GHz) at this particular LSD. Analysis of the simulated structures shows that the union of gate-drain field plate boosts the VBr while decreasing the Ron, resulting in improved electrical performance and a wider application range.

Kinetics study and bio-phase characteristics of drainage in paddy fields purified by a compound ecological ditch

Kinetics study and bio-phase characteristics of drainage in paddy fields purified by a compound ecological ditch

Analysis of breakdown voltage for GaN MIS-HEMT with various composite field plate configurations and passivation layers

The effects of different field plate designs on the breakdown voltage of GaN Metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) were examined in this study. The study's primary goal was to determine the dependence of breakdown voltage with respective to composite field plate designs using TCAD simulation. For devices featuring only G-FP, with a fixed gate to drain distance of 15 μm and a fixed G-FP to drain distance of 15 μm, the maximum breakdown voltage was achieved 1 μm G-FP. Breakdown voltage trends were also determined for composite field plate configurations, such as adding a source field plate (S-FP) or a drain field plate (D-FP) with a fixed 1 μm G-FP length. A further enhancement in device breakdown performance was demonstrated by employing a novel D-FP structure. A single D-FP improves the breakdown voltage from 1.4 kV (conventional breakdown voltage with 1um G-FP) to 1.6 kV when combined with 1 μm G-FP, while the novel two-step D-FP achieves a breakdown voltage of about 1.7 kV when combined with 1 μm G-FP. We also investigated the influence of high-k dielectric passivation layers on the breakdown voltage. The breakdown voltage of the devices with optimized G-FP can be further improved by using high-k dielectric material as a passivation layer. The thorough investigations contribute to a better understanding of GaN MIS-HEMT breakdown characteristics and prospective pathways for improving their performance via unique field plate designs and superior dielectric materials.

Two-stage channels can enhance local biodiversity in agricultural landscapes

Field drainage causes habitat loss, alters natural flow regimes, and impairs water quality. Still, drainage ditches often are last remnants of aquatic and wetland habitats in agricultural landscapes and as such, can be important for local biodiversity. Two-stage channels are considered as a greener choice for conventional ditches, as they are constructed to mimic the structure of natural lowland streams providing a channel for drainage water and mechanisms to decrease diffuse loading. Two-stage channels could also benefit local biodiversity and ecosystem functions, but existing information on their ecological benefits is scarce and incomplete. We collected environmental and biological data from six agricultural stream systems in Finland each with consequent sections of a conventional ditch and a two-stage channel to study the potential of two-stage channels to enhance aquatic and riparian biodiversity and ecological functions. Biological data included samples of stream invertebrates, diatoms and plants and riparian beetles and plants. Overall, both section types were highly dominated by few core taxa for most of the studied organism groups. Riparian plant and invertebrate communities seemed to benefit from the two-stage channel structure with adjacent floodplains and drier ditch banks. In addition, two-stage channel sections had higher aquatic plant diversity, algal productivity, and decomposition rate, but lower stream invertebrate and diatom diversity. Two-stage channel construction did not diversify the structure of stream channels which is likely one explanation for the lack of positive effects on benthic diversity. However, both section types harbored unique taxa found only in one of the two types in all studied organism groups resulting in higher local gamma diversity. Thus, two-stage channels enhanced local biodiversity in agricultural landscapes. Improvements especially in aquatic biodiversity might be achieved by increasing the heterogeneity of in-stream habitat structure and with further efforts to decrease nutrient and sediment loads.

Influence of irrigation water and soil on annual mercury dynamics in Sacramento Valley rice fields.

Methylmercury (MeHg) is a human and environmental toxin produced in flooded soils. Little is known about MeHg in rice (Oryza Sativa L.) fields in Sacramento Valley, California. The objectives of this study were to quantify mercury fractions in irrigation water and within rice fields and to determine their mercury pools in surface water, soil, and grain. Soil, grain, and surface water (dissolved and particulate) MeHg and total mercury (THg) were monitored in six commercial rice fields throughout a winter fallow season and subsequent growing season. Both dissolved and particulate mercury fractions were higher in fallow season rice field water. Total suspended solids and particulate mercury concentrations were positively correlated (r=0.99 and 0.98 for THg and MeHg, respectively), suggesting that soil MeHg was suspended in the water column and potentially exported. Dissolved THg and MeHg concentrations were positively correlated with absorbance at 254nm (r=0.47 and 0.58, respectively) in fallow season field water. In the growing season, fields with higher irrigation water MeHg concentrations (due to recycled water use) had elevated field-water MeHg (r=0.86) and grain MeHg concentrations (r=0.96). Based on a mass balance analysis, soil mercury pools were orders of magnitude larger than surface water or grain mercury pools; however, fallow season drainage and grain harvest were the primary pathways for MeHg export. Based on these findings, reducing (1) discharge when water is turbid, (2) straw inputs, and (3) use of recycled irrigation water could help reduce mercury exports in rice field drainage water.

Influence of Pleistocene glacial deposits on the transport of agricultural nitrate in the river Wensum catchment, UK

Mitigating NO3− pollution requires an understanding of the hydrological processes controlling contaminant mobilisation and transport, particularly in agricultural catchments underlain by Pleistocene glacial deposits. Focusing on the Wensum catchment in East Anglia, UK, precipitation (n = 20), stream water (n = 50), field drainage (n = 22) and groundwater (n = 84) samples collected between February–March 2011 and April–September 2012 were variously analysed for water stable isotopes (δ2HH2O and δ18OH2O), the dual-isotopes of NO3− (δ15NNO3 and δ18ONO3), groundwater residence time indicators (CFCs and SF6) and hydrochemical parameters. The residence time indicators suggested a component of modern (post-1960) groundwater throughout the sequence of glacial deposits that corresponds with the penetration of agricultural NO3−. Denitrification and lower NO3− concentrations (<8 mg L−1) are observed in the glacial tills, compared with higher NO3− concentrations (<90 mg L−1) observed under more oxidising conditions in the glacial sands and gravels. Storm hydrograph separation for two storms in April and September 2012 using two- and three-component mixing models showed a faster response with field drainage (36–38 %) and baseflow (5–37 %) contributing to the total stream discharge in areas of clay loam soils over glacial tills. In these areas, the dual stable isotopes of NO3− (δ15NNO3 = +11.8 ‰ and δ18ONO3 = +7.1 ‰) indicated a denitrified source of nitrogen from field drainage and groundwater. In comparison, a dampened response and a higher percentage of baseflow (29–80 %) was observed in areas of sandy clay loam soils over glacial sands and gravels. In these areas, mean NO3− isotopic signatures (δ15NNO3 = +7.8 ‰ and δ18ONO3 = +5.0 ‰) indicated a source of nitrified NH4+. In conclusion, understanding hydrological processes in catchments underlain by variable glacial deposits can inform nutrient management plans and cultivation practices to reduce the risk of agricultural NO3− contamination.

Hydrological effects of open ditch damming and controlled subsurface drainage in a Nordic agricultural field

Abstract Controlled drainage (CRD) is an agricultural water management practice designed to adjust the capacity of a drainage system under varying hydrological conditions. This simulation study aimed to quantify the potential of combining a controlled subsurface drainage (CS) with open ditch damming (CD) to manage the water table depth (WTD) and field water balance in Nordic conditions. Simulations with and without controlled drainage were run using a hydrological model that had been set up for a flat loamy field in Northern Ostrobothnia, Finland, for the period 2010–2021. All CRD scenarios reduced the probability of deep WTDs during growing seasons (May–Sep). The impact of CS on WTDs was greater and more uniform than CD. The CRD effects on water balance were seen in water outflow pathways, as CS reduced drain discharge while CD had the opposite effect. When both methods were applied simultaneously, annual evapotranspiration increased 5–12% compared with the free drainage scenario. The effects of CRD on evapotranspiration were greatest during the dry years indicating that CRD has potential to reduce drought in food production areas. None of the CRD scenarios could maintain optimal WTDs during the entire growing season, highlighting the complexity of optimizing field water management using CRD alone.

Mobilization of Cadmium and Arsenic During Anoxic-Oxic Alteration in Paddy Soils: A Vital Role of Manganese

ABSTRACT Flooding and drainage of paddy fields can induce the activation of soil cadmium (Cd)/arsenic (As), which will accumulate in rice grains and threaten human health. Mn oxides influence soil Cd and As availability, but few detailed studies have been reported on how Mn redox simultaneously affects Cd and As mobility during flooding and drainage. Two paddy soils with various Mn contents were incubated under three redox conditions, namely 30-d reduction, 30-d oxidation and 20-d reduction subsequent with 10-d oxidation, to investigate Cd and As migration. During reduction, the soil abundant in native Mn oxides possessed more high-valence Mn oxides, which promoted As oxidation and retarded the reductive dissolution of Fe (oxyhydro)oxides, thereby decreasing As mobility. Cd mobility mainly depended on the conversion between Fe-Mn oxides-bound Cd and exchangeable Cd. The high Mn content was conducive to decreasing Cd mobilization. Furthermore, the oxidation of As in soils was linked with a Fenton-like effect. The generated hydroxyl radicals (•OH) decreased with oxidation and the oxidation of Mn(II) by •OH inhibited As migration but promoted Cd activation. In summary, the mobility of Cd and As was lower in Mn rich soils, which may involve the immobilization, oxidation and catalytic effects of Mn oxides.

Simulation Study on Water Quality of Paddy Field Ditches Considering the Effects of Rainfall and Sediment Release

As the main channel for the drainage of paddy fields, the water quality of canals directly affects the water quality of surrounding water bodies. Factors such as rainfall and the release of accumulated pollutants from the sediment of the canals have a direct impact on the water quality of drainage ditches. Based on the measured hydrological and water quality data, a dynamic water quality model was built to simulate the runoff and water quality changes in a paddy field for different return periods (1, 2, 5, 10, 20, and 50 years), and to consider the effects of released drainage sediment on the water quality of the paddy field. The change in water quality in paddy fields and ditches in different periods was studied. The simulation results showed that under different return periods, the total nitrogen concentration and total phosphorus concentration in the water of the paddy field and ditch increased first, and then decreased with time in June and July–September, while the pollutant concentration remained basically stable after the end of rainfall. With the increase in return period, the total nitrogen concentration and total phosphorus concentration decreased gradually. The release of nitrogen and phosphorus from the sediment of ditches resulted in an increase in the total nitrogen concentration and total phosphorus concentration in the ditches, and an increase in the pollution load. Under the influence of rainfall and fertilizer, the total nitrogen concentration and total phosphorus concentration in paddy ditch drainage were generally higher and more polluted in June than in July–September, and under the influence of released sediment, the ditch drainage was most polluted in June when the return period was one year, with the total nitrogen concentration and total phosphorus concentration at the outlet of the paddy ditch reaching 21.63 mg/L and 0.88 mg/L, respectively. The research results can provide a theoretical basis and basic support for the interception and treatment of non-point source pollution in farmland.

Effects of Nitrogen Input and Aeration on Greenhouse Gas Emissions and Pollutants in Agricultural Drainage Ditches

Understanding the patterns of greenhouse gas emissions and the changes in pollution load in terrestrial freshwater systems is crucial for accurately assessing the global carbon cycle and overall greenhouse gas emissions. However, current research often focuses on wetlands and rivers, with few studies on agricultural drainage ditches, which are an important part of the agricultural ecosystem. Investigating the greenhouse gas emission patterns and pollution load changes in agricultural drainage ditches can help accurately assess the greenhouse effect of agricultural systems and improve fertilization measures in farmlands. This study explored the effects of nitrogen input and aeration on the pollution load and greenhouse gas emission processes in paddy field drainage ditches. The results showed that aeration significantly reduced the concentration of ammonium nitrogen (NH4+) in the water, decreased the emissions of nitrous oxide (N2O) and methane (CH4), and slightly increased the emission of carbon dioxide (CO2), resulting in an overall reduction of the global warming potential (GWP) by 34.02%. Nitrogen input significantly increased the concentration of ammonium nitrogen in the water, slightly reduced the emissions of N2O and CH4, and increased the CO2 emissions by 46.60%, thereby increasing the GWP by 15.24%. The drainage ditches reduced the pollution load in both the water and sediment, with the overall GWP downstream being 9.34% lower than upstream.