Agricultural Drainage Research Articles

Isolating Indigenous Metal Resistant Gram-Positive Bacteria: Assessing Their Selenite Reduction Potential

The objective of this study is to isolate gram-positive bacilli from soil and to study the effects of physiological parameters on their heavy metal resistance. High levels of metals in the soil can have major toxic effects on soil microorganisms and may cause a great change in the species diversity and population sizes of soil microbes. In current study soil samples were collected from the agriculture drainage water and soil in Lahore. After the selection of sixty gram-positive strains, their biochemical and metabolic profile was structured and all were auxin producing. The isolates were resistant to multiple heavy metals including Ni. Pb, Cr, Li and Hg. Their selenite reduction was estimated at varyingpH, Temperature and concentrations of selenite and all were resistant upto 3000 ?g/ml, However, their efficacy of reducing selenite was majorly affected by set physiological parameters.

Influence of the use of remediated soil and agricultural drainage water on the safety of tomato fruits

The objective of this study is to assess the effectiveness of different techniques employed in remediating contaminated soil and wastewater ecosystems to ensure the safety of tomato fruits (Solanum lycopersicum L. var. cerasiforme) cultivated in these environments. Three biochemical techniques T1–T3, besides two controls CCU and CCT, were used to remediate contaminated soil ecosystems using rock phosphate, elemental sulfur, bentonite, phosphate-dissolving bacteria, and Thiobacillus sp. The contaminated agricultural drainage water was remediated by a down-flow hanging sponge (DHS) system. Two experiments were conducted: a pot experiment took place in the greenhouse at the National Research Center of Cairo (Egypt) and a field experiment was carried out at the basin site in the village of El-Rahawy, applying the optimal treatment(s) identified from the greenhouse experiment. The health risk assessment for potentially toxic elements (PTEs) in the harvested tomato fruits was conducted by calculating estimated daily intake (EDI) and target risk quotient (THQ) values. Results from the greenhouse experiment indicated the high effectiveness of the DHS technique in remediating El-Rahawy agricultural drainage water. The content of PTEs after remediation was significantly reduced by 100%, 93.3%, 97.8, and 77.8% for cadmium, copper, manganese, and zinc, respectively. The application of treated drainage water in employed reclaimed soil ecosystems led to a remarkable decrease in PTE levels, especially under T3 treatment; the reduction reached 89.4%, 89.5%, and 78.4% for nickel, copper, and zinc, respectively. The bioremediation technique also reduced the content of PTEs in tomato fruits harvested from both greenhouse and field experiments; the cadmium content, for example, was below detection limits in all treatments. The T3 treatment applied in the greenhouse experiment caused the highest percentage decrease among the employed PTEs in tomato fruits grown in the greenhouse. The same trend was also reached in the field experiment. Microbiological analyses of tomato fruits revealed that E. coli, Salmonella, or S. aureus bacteria were identified on tomato fruits harvested from either greenhouses or field experiments, showing that the counted total bacteria were higher under the field experiment compared to the greenhouse experiment. The health risk assessment parameter THQ was below 1.0 for all tested metals under all treatments. This means that no potential health risk is expected from consuming tomato products produced under the different employed remediation treatments. In conclusion, the employed bioremediation techniques successfully reduced the PTE content and microbial load in both soil and drainage water ecosystems and in harvested tomato fruits. Henceforth, no health risks are expected from the consumption of this product.

Performance of an integrated sediment interceptor in removing phosphorus from agricultural drainage water

Reducing phosphorus (P) loss from agricultural drainage water is challenging. In this study, we aimed to remove P from agricultural drainage water by developing an integrated sediment interceptor with adsorbent modules filled with Zr/Zn nanocomposite-modified ceramsite (ZMC-interceptor). The results of sequential chemical extraction and 31P NMR showed that the contents of H2O-P (1.15 % of total P), NaHCO3-Pi (10.48 % of total P), and ortho-P (orthophosphate, 90.6 % of total P) in the sediments of the ZMC-interceptors were higher than those in nearby field soils. The average enrichment ratios of particulate P (PP, >450 nm), medium-colloidal P (MCP, 220–450 nm), fine-colloidal P (FCP, 1–220 nm), and truly dissolved P (Truly DP, <1 nm) in the sediment over the field soil were 1.37, 1.21, 1.70, and 3.01, respectively. No significant differences were found in the sediment P-trapping function with and without ZMC integrated sediment interceptors. However, the ZMC-interceptors remarkably reduced total P (39.7 % for influent concentrations of 0.19–0.68 mg L−1) from agricultural drainage water compared to those unmodified ceramsite-interceptors (21.7 % for influent concentrations of 0.17–0.66 mg L−1) during the drainage ‘window period’ (June–August 2022). This was mainly due to the higher removal efficacies of MCP (19.7 %), FCP (23.3 %), and Truly DP (34.8 %) of the ZMC-interceptors. This study highlighted that the ZMC-interceptor not only trapped P in the sediment but also facilitated the removal of different-sized P fractionated from agricultural drainage water.

Reduction of some Heavy Elements of Agricultural Drainage Water using the Azolla Plant (Azolla)

The study was conducted at the Faculty of Science, University of Tikrit and included alaboratory experiments to estimate the proportion of some heavy elements (lead, potassium, cadmium, magnesium, iron) in the biomass ofAzolla pinnata plant to estimate its biocontrol ability to treat agricultural drainage water as samples were taken from the Azolla pinnata cultivated in two different types of agricultural drainage water and Tape water to estimate the percentage of elements before treatment in the water and after it at three periods (21,14,7) days. The results revealed Increasing the concentration of potassium, lead and magnesium elements in the extracted biomass of Azolla pinnata samples after treatmentof agricultural drainage water (1,2) while this increase was slight in tap water, as for cadmium, the results showed a decrease in its concentration in extracted biomass of A. pinnatasamples grown in agricultural drainage water (1,2) and tap water, and that the were non-significant differences (P &lt;0.05) in the concentration ofiron element in extracted plant samples grown in agricultural drainage water1 as it remained at its concentration (2.69 ±0.00) during the three weeks, it also maintained its concentration in the samples of the extracted plant grown in tap water, reaching(2.86 ± 0.00), while the result shows there was a slight decrease in the concentration of Iron inthe extracted plant in treated agricultural drainage water 2, reaching (2.86) in the first week, decreasing to (2.69±0.00) in the second and third week.

Bacterial diversity in agricultural drainage ditches shifts with increasing urea-N concentrations.

Urea-based fertilizers applied to crop fields can enter the surface waters of adjacent agricultural drainage ditches and contribute to the nitrogen (N) loading in nearby watersheds. Management practices applied in drainage ditches promote N removal by the bacterial communities, but little is known about the impacts of excess urea fertilizer from crop fields on the bacterial diversity in these ditches. In 2017, sediments from drainage ditches next to corn and soybean fields were sampled to determine if fertilizer application and high urea-N concentrations alters bacterial diversity and urease gene abundances. A mesocosm experiment was paired with a field study to determine which bacterial groups respond to high urea-N concentrations. The bacterial diversity in the ditch next to corn fields was significantly different from the other site. The bacterial orders of Rhizobiales, Bacteroidales, Acidobacteriales, Burkholderiales, and Anaerolineales were most abundant in the ditch next to corn and increased after the addition of urea-N (0.5mg N L-1) during the mesocosm experiment. The results of our study suggests that urea-N concentrations >0.07mg N L-1, which are higher than concentrations associated with downstream harmful algal blooms, can lead to shifts in the bacterial communities of agricultural drainage ditches.

Agricultural drainage pipe in Guadua angustifolia: implications of Manning roughness in Pitalito forest stands

Water extraction in agricultural fields with high saturation levels requires drainage systems that increase land preparation costs, so looking for new options for materials that function as drainage pipes that provide a better technical–economic relationship is crucial. In this study, Manning roughness values were analyzed in the culms of Guadua angustifolia considering three factors: flow, section, and location site of the forest stands. This study was carried out in the rural area of the municipality of Pitalito; the characterization of culms was made based on the Colombian technical standards (NTC) 5726 and 5727, the cutting and elaboration of test pieces according to the NTC 5525, and finally, the hydraulic tests were carried out. The roughness values oscillated between 0.1089 and 0.0337 according to the different flow evaluated values in the laboratory tests, between 0.1004 and 0.0356 for the sections analyzed, and between 0.0909 and 0.0533 according to the sample extraction area. The multifactor ANOVA established a significant relationship for the flow and section on the Manning n roughness, while the zone was insignificant.

Flood damage cost prediction using random forest

Floods are one of nature's deadliest catastrophes, causing permanent and catastrophic damage on the socioeconomic system, agriculture and human life. The problems arise when floods could cause a lot of economic damage such as damage to buildings, agriculture and others. Flood damage estimation is a subject of study that has not received much attention. The objective of this research is to explore the Random Forest algorithm in the flood damage cost prediction. The damages specified by the Malaysia’s Department of Irrigation (JPS) are structures such as culverts, MTB bridges, riverbank ruins, concrete main channels, farm roads, hydrological stations, agricultural and water drainage, JPS pump houses and tyres in Terengganu. Terengganu is one of the states in Malaysia which has to endure floods during the monsoon season by the end of the year. The methods employed in this research include data collection, data pre-processing, backend engine coding and user interface design. This project was implemented using the Python programming language. The data were collected from the annual flood report provided by the JPS Negeri Terengganu. The research used the rainfall and streamflow data from the year 2012 to 2022 as attributes to forecast the cost of the JPS structures damages in Terengganu. The prediction results showed that the best model achieved the accuracy of 91.47% with a Mean Squared Logarithmic Error (MSLE) of 0.48 and Coefficient of Determination (R2) of 0.92. In the performance evaluation, the model with 80:20 training and testing data ratio produced the best result in predicting the flood damage cost. The potential enhancements to this research involve extending the scope to encompass all Malaysian states, incorporating diverse flooded structures and adding more input variables for a more improved and more reliable flood prediction system.

Workshop Pemahaman Gen Z tentang Banjir dan Pencegahan

Flooding is an event that occurs as a result of the accumulation of water and cannot be accommodated by the soil.Flooding in Jakarta has become a routine problem over time, due to natural and human factors faced by the DKI Jakarta community.Losses caused by floods, especially indirect losses Not only the physical impacts suffered by the community but also non-physical losses such as schools being demolished, prices of basic necessities rising, and sometimes even deaths. Kodoatie and Syarief (2006) provide some examples of flood impacts or losses, loss of life or injury, property loss, settlement damage, trade area damage, industrial area loss, agricultural land damage, drainage and irrigation system damage, road and railway damage, highways, bridges, and airports damage, telecommunications system damage. Then the DKI Jakarta Regional Government coordinates with the Central Government to address the problem, the flood management policies are divided into short, medium and long-term periods. (Handayani, 2013). In this service to the community, there is an understanding of flooding and persecution using the method of devotion to the society in the form of socialization. This activity was followed by 24 people of the Generation Z, this Socialization has the theme “Flood Prevention and Management”. The purpose of this socialization is to expect the generation Z to gain a better understanding of the Flood and to emphasize the sense of self-awareness not to take actions that aggravate the flood.

Effect of Environmental Variables on Zooplankton in Various Habitats of the Nile River

The present study investigated the effect of environmental variables on the abundance and distribution of zooplankton in different habitats along the Nile River in Shattura Village. Zooplankton samples were collected from three distinct sites along the Nile River in Shattura Village, each exhibiting different environmental characteristics: Site 1 with vegetation, site 2 lacking vegetation, and site 3 being a drain canal. The study spanned from spring 2020 to winter 2021, during which the physico-chemical parameters of the water were analyzed. Rotifera constituted the majority of the zooplankton (54.73%), followed by Cladocera (20.59%), Copepoda (13.1%), and Ostracoda (8.9%). Among the 52 identified zooplankton species, Rotifera comprised 18 species, Cladocera 13 species, Copepoda 10 species, and Ostracoda 11 species. Site 1 exhibited the highest zooplankton density (44.08%), attributed to the presence of vegetation, followed by site 3 (37.18%), influenced by agricultural drains, and site 2 had the lowest density (18.73%). Zooplankton abundance peaked in summer and declined in winter. Notably, Rotifera abundance increased in populated sites (site 3), whereas other zooplankton groups thrived in less populated areas. Correlation analyses revealed positive associations between Rotifera and Cladocera with electric conductivity, total dissolved solids (TDS), chloride (Cl), calcium (Ca), and sulfate (SO4). Conversely, Copepoda showed positive correlations with water transparency, pH, dissolved oxygen, and biological oxygen demand (BOD). Overall, seasonal variations significantly impacted the zooplankton community, with Rotifera dominating and Ostracoda being the least abundant. High values of the Shannon–Weaver diversity index, richness, and evenness suggested ample food resources and favorable growth conditions. Transparency, conductivity, pH, dissolved oxygen, and BOD were identified as the key influencing parameters on zooplankton abundance. Additionally, vegetation and agricultural drains strongly influenced total zooplankton levels.

Improving irrigated maize (Zea mays L.) production with saline agricultural drainage water using drip irrigation system and organic mulches: Field study and simulation modelling

Due to the scarcity of fresh water in dry areas, including Egypt, emphasis has been placed on the importance of studying non-traditional water sources as an alternative source of irrigation. Therefore, this research aimed at investigating the impact of saline agricultural drainage water, drip irrigation and organic mulching using rice straw on maize water productivity under Egypt’s arid condition. The field experiment included sixteen treatments during two seasons, 2022 and 2023. Irrigation systems were [Furrow irrigation system (FIS) and drip irrigation system (DIS)] while saline agricultural drainage water strategies were [FW (0.55 dS/m), SW1 (1.35 dS/m), SW2 (3 dS/m) and SW3 (5 dS/m)] represented as sub main plot and organic mulching using rice straw (OMRS) was also investigated. The highest MY values were achieved with DIS with FW and also with irrigation with salty agricultural drainage water, with the necessity of using organic mulches of rice straw. The highest MY values were achieved as a result of achieving the best water-salt balance within the root propagation zone. The highest values were 10.89 t/ha with FW and there were no significant differences between them and the values of 10.83 t/ha when irrigated with saline agricultural drainage water for 2022 and the similar results were achieved during the 2023 season. Based on the above, SW1 can be used directly without mixing with FW1 if the ability of the grown plant to tolerate the level of salinity concentration, with the necessity of using organic mulches. The SALTMED model simulated reasonably well the soil moisture and soil salinity as well as maize yield and for all treatments, with R2 of 0.87, 0.98 and 0.96, respectively.

Land drainage functioning and hydrological impacts in rural catchments: model development and field experiments

The development of an integrated theory of subsurface drainage based on hydrology and hydrogeology concepts is presented. The historical context, the main hypothesis derived from the Boussinesq equation and the validation of the model predictions are discussed. Theoretical developments of this equation demonstrate that a single parameter (σ)—a combination of soil and drainage system properties—is sufficient for predicting the dynamics of subsurface drain flow rates. We also demonstrate that these drain flow rates are a function of the level of water replenishment in the system (classically the water table elevation), of the recharge intensity of the aquifer and of a buffer function related to the swelling or deflation of the water table shape during recharge events. For values of σ>1, the buffer role of the water table is negligible. In that case approx. 13% of the water table recharge contributes to the flow rate, which is shown to explain the observed disconnection between water table elevations and peak flow rates at the outlet of classic agricultural drainage systems and to predict these peak flow rates accurately. A modelling approach based on this theory and validated experimentally (SIDRA model) allowed us to test the quality of the peak flow prediction. The SIDRA model also includes a surface runoff module and has been coupled to different modelling tools and used to analyse the impacts of subsurface drainage on water quality. The approach contributed towards the development of tools that helped to connect better the drainage systems to the hydrological functioning of watersheds.

Identification of water pollution sources and analysis of pollution trigger conditions in Jiuqu River, Luxian County, China.

Against the backdrop of ecological conservation and high-quality development in the Yangtze River Basin, there is an increasing demand for enhanced water pollution prevention and control in small watersheds. To delve deeper into the intricate relationship between pollutants and environmental features, as well as explore the key factors triggering pollution and their corresponding warning thresholds, this study was conducted along the Jiuqu River, a strategically managed unit in the upstream region of the Yangtze River, between 2022 and 2023. A total of seven monitoring sites were established, from which 161 valid water samples were collected. The k-nearest neighbors mutual information (KNN-MI) technique indicated that water temperature (WT) and relative humidity (RH) were the main environmental factors. The principal component analysis (PCA) of ten water quality parameters and three environmental factors unveiled the distinguishing characteristics of the primary pollution sources. Consequently, the pollution sources were categorized as treated wastewater > groundwater runoff > phytoplankton growth > abstersion wastewater > agricultural drainage. Furthermore, the regression decision tree (RDT) algorithm was used to explore the combined effects between pollutants and environmental factors, and to provide visual decision-making process and quantitative results for understanding the triggering mechanism of organic pollution in Jiuqu River. It conclusively identifies total phosphorus (TP) as the predominant triggering parameter with the threshold of 0.138mg/L. The study is helpful to deal with potential water pollution problems preventatively and shows the interpretability and predictive performance of the RDT algorithm in water pollution prevention.

The Performance and Feasibility of Solar-Powered Desalination for Brackish Groundwater in Egypt

With a deficit of about 20 BCM in 2022, Egypt faces a severe water shortage due to rapid population growth (109.3 million in 2022). Egypt launched a program to utilize non-conventional water sources, like treated wastewater, agriculture drainage water, and desalination. Egypt is expanding its non-conventional water resources, boosting desalination capacity from 86,000 m3/day in 2015 to 680,000 m3/day in 2022, with plans to reach 1,250,000 m3/day by 2025. Despite the improvements in desalination technologies and cost, its high energy use and environmental impacts are still limiting its use. Egypt’s desalination relies on grid electricity, but renewable energy is crucial for remote areas where no electricity grid exists. Scaling up renewable energy in desalination faces challenges like land availability and high costs. GIS was used for optimal site selection for a brackish groundwater solar desalination plant in the Western North Nile Delta. Factors like solar radiation, groundwater quality, aquifer potentiality, geology, and seawater intrusion were carefully assessed. An evaluation of a sustainable 1000 m3/day solar-powered RO desalination pilot plant’s economic and technical viability is provided, along with its performance assessment. Limitations, challenges, and potential improvements are discussed. The study finds that RO–PV desalination for brackish groundwater is technically mature, with competitive Capex costs (USD 760-USD 850/m3) and low Opex (USD 0.55–USD 0.63/m3). Solar desalination for brackish groundwater with salinity less than 23,000 ppm can reduce energy consumption to 3.6–4.2 kWhr/m3. Water storage and hybrid systems with solar and conventional energy are suggested to enhance efficiency. This implies a growing market for small- to medium-scale RO solar-powered desalination in remote areas in the near future.

IMPACTS OF INTENSIVE AGRICULTURE ON BIRDS: A REVIEW

Intensive agriculture has had a negative impact on biodiversity and human health across the world. Specifically, bird populations have declined for many years due to soil degradation and agrochemical pollution. This review, which draws on 890 sources, including research articles and literature reviews, examines the interaction between birds and intensive agriculture to better understand its effects and conservation implications. Intensive agricultural activities have resulted in significant population declines among insectivorous and carnivorous birds, while generalist bird populations have increased. The heavy use of pesticides in intensive agriculture affects food availability for birds by reducing invertebrate and vertebrate populations as well as natural vegetation cover, which has a significant impact on bird diversity. Additionally, the accumulation of toxic compounds reduces bird reproductive success. In general, intensive agroecosystems have consistently had lower avian diversity than forest habitats and even lower-impact agricultural systems. However, some agroecosystems, such as rice fields, agricultural drainages, and canal systems, create alternative habitats that can benefit waterfowl. Future work should consider strategies such as restoring and enhancing vegetation edges, preserving natural vegetation, implementing organic farming practices, maintaining water bodies, and providing economic incentives for landowners to conserve biodiversity on their land to promote bird diversity conservation.

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.

Phosphorus removal from agricultural tile drainage effluent with activated alumina in novel adsorption reactors.

Subsurface tile drains under agricultural field crops are a major source of phosphorus (P) discharge to aquatic ecosystems, contributing to the eutrophication of surface waters. Adsorption reactors for P removal from drainage water (P-reactors) could reduce P outflow from agricultural land but were rarely studied in cold, temperate climates. In our study, four low-cost P-reactors were installed in agricultural fields in south-central Québec, Canada. Activated alumina (AA) beads were used as P-adsorptive material, and the reactors were connected to tile drain outlets. Paired water samples (39 events) from reactor inlets and outlets were analyzed for P species and other physicochemical parameters during one calendar year to assess the P removal from tile drain effluent in the P-reactors. Collectively, the P-reactors retained approximately half (48%) of the total mass of P flowing through the tile drains, mostly (92%) as particulate P. The mass of AA beads adsorbed 11% of the dissolved-P fractions. Results are interpreted in the context of the field drainage area and will require adjustments to the P-reactor design to accommodate larger fields. The P-reactors remained structurally intact throughout all four seasons in a cold temperate climate, showing the potential of simple, inexpensive P-reactors to reduce P concentration in tile drain effluent.

Online coupling of miniaturized HPLC and high performance thin layer chromatography by a fractionation unit for effect directed analysis

The rising discharge of anthropogenic chemicals into aquatic environments poses a significant threat, necessitating effective monitoring strategies. This study introduces an innovative approach to effect-directed analysis (EDA) by coupling liquid chromatography (LC) with high-performance thin-layer chromatography (HPTLC), utilizing a modified MALDI spotter. The objective is to optimize fractionation parameters for sample application and assess the method's viability in identifying acetylcholinesterase (AChE) inhibitors, specifically malathion, parathion, and chlorfenvinphos.The optimization process involves controlling sample volume, spot shape, and spot distances on HPTLC plates. Successful application is demonstrated by a miniaturized LC system coupled to the HPTLC plate via spotter, allowing effective separation and identification of AChE inhibitors. The study further explores the method's application to water samples from a river with predominantly agricultural drainage area.Spiked samples reveal distinct active spots, identified through extraction and subsequent high-resolution mass spectrometry (HRMS) measurements. However, results indicate the absence of AChE inhibitors in non-spiked water samples, affirming the efficacy of the EU ban on most organophosphate pesticides. The usefulness of HPTLC in separation of coeluting substances from HPLC is emphasized, demonstrating its suitability for the effect-directed analysis of complex samples.This work shows the integration of HPTLC with liquid chromatography for EDA, offering a powerful tool for identifying and monitoring AChE inhibitors in water samples. The approach addresses limitations in current monitoring strategies and provides insights into the presence and impact of chemicals in aquatic ecosystems. The study contributes to ongoing efforts to enhance water quality monitoring, aligning with the principles of the EU Water Framework Directive.

Two thousand years of garden urbanism in the Upper Amazon.

A dense system of pre-Hispanic urban centers has been found in the Upano Valley of Amazonian Ecuador, in the eastern foothills of the Andes. Fieldwork and light detection and ranging (LIDAR) analysis have revealed an anthropized landscape with clusters of monumental platforms, plazas, and streets following a specific pattern intertwined with extensive agricultural drainages and terraces as well as wide straight roads running over great distances. Archaeological excavations date the occupation from around 500 BCE to between 300 and 600 CE. The most notable landscape feature is the complex road system extending over tens of kilometers, connecting the different urban centers, thus creating a regional-scale network. Such extensive early development in the Upper Amazon is comparable to similar Maya urban systems recently highlighted in Mexico and Guatemala.

Flow Rate and Volume Estimates from Variable Frequency Drive Operated Drainage Sump Pumps

Highlights This article provides an overview of operations and benefits of using a variable frequency drive to operate agricultural subsurface drainage system sump pumps. A methodology is proposed to monitor flow rates leaving agricultural subsurface drainage pump stations via a MATLAB algorithm. The results of this research were mixed because the algorithm estimates did not always match with the corresponding flowmeter measurements. Abstract. Subsurface drainage plays a crucial role in excess water removal through perforated pipes buried in the soil. The Red River Valley of eastern North Dakota and west central Minnesota often requires pumped drainage outlets due to its flat topography, with many modern systems incorporating variable frequency drives (VFD) for improved efficiency. VFDs adjust pump speeds to match drainage needs, but this dynamic operation complicates accurate flow rate estimation for edge-of-field monitoring. This project aimed to devise an automated method for calculating flow rate estimates from VFD pumping systems involving tank geometry, operational water levels, and pump duty cycling. Linear regressions with calibration data from a transit-time ultrasonic flowmeter produced mixed outcomes. Some linear regressions revealed errors in calculated versus measured flow rate of =14%, while other regressions showed errors nearing 40%. To address this, future efforts should explore methods incorporating the pump’s electrical characteristics. This approach would provide a more accurate representation of the unstable and intricate pumping operations during transient conditions. Keywords: Edge-of-field monitoring, Flow rate, Pump, Red River Basin, Subsurface drainage, Variable frequency drive

Agricultural Drainage, Water Pollution, and Biotic Health in the USA Cornbelt

A stable landscape balances geologic fragility, climate change and land use. In the USA Cornbelt, land improvement contractors have moved earth to fill wetlands, build ditches and plow in varying diameters of subsurface pipe to alter the hydrology and natural watershed plumbing. Nonpoint source (NPS) pollution from rural sediment and nutrients remains the most difficult challenge to meeting water quality standards in the USA. Cornbelt states have invested in nutrient management plans to reduce the nitrogen and phosphorus loads to the Gulf of Mexico, and most local levels of government are engaged in water quality planning to reduce sediment, bacteria, and nutrient impacts on local lakes and streams. Rural drainage systems constructed decades ago need upgrading because of changes in cropping technology and climate. However, drainage engineers/contractors need 21st century technology to upgrade water management. Downstream flooding, infrastructure damage and loss of aquatic habitat have been observed systemically in the Midwestern USA. States have set goals to reduce NPS pollution, yet a proposed drainage improvement could degrade ecosystem services. The drainage authority/engineer needs a protocol/model to better assess water management by examining the fluvial processes within, at and below the outlet of a proposed drainage project.