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agriculturalwatersheds, etc ; electron microscopy; forestry; titanium; titanium dioxide; Show all 5 Subjects
Abstract:
... Surface waters from three catchments having contrasting land-uses (forested, agricultural, and urban) were sampled monthly and analysed for nanoparticulate titanium dioxide (NPs-TiO₂) by single particle ICPMS and electron microscopy. We report one-year of data for NPs-TiO₂ having average number and mass concentrations of 9.1 × 10⁸ NPs-TiO₂ particles L⁻¹ and 11 µg NPs-TiO₂ L⁻¹ respectively. An incr ...
agriculturalwatersheds, etc ; automation; hysteresis; land use; storms; stream flow; time series analysis; turbidity; water quality; Show all 9 Subjects
Abstract:
... The advent of in situ optical sensors that can collect sub‐daily measurements of nutrients and turbidity in flowing water bodies has yielded comparatively much larger water quality data sets than were previously available. With these newly available data sets, there has been increased interest in studying event‐based concentration‐discharge (c‐Q) relationships to infer the sources and pathways of ...
agriculturalwatersheds, etc ; base flow; nonpoint source pollution; parameter uncertainty; rain; resource allocation; surveys; time series analysis; China; Show all 9 Subjects
Abstract:
... Accurate baseflow quantification is an important step in the survey and evaluation of water resources, non‐point source pollution quantification, and optimization of water resource allocation. We selected a typical agricultural watershed with high precipitation rates in eastern China as the study area and investigated the impact of the combination of a recession constant (on an annual, monthly, or ...
agriculturalwatersheds, etc ; algorithms; data collection; equations; model validation; models; rain; rainfall simulation; rill erosion; runoff; sediment transport; soil; soil quality; Show all 13 Subjects
Abstract:
... Water erosion is the main cause of soil degradation in agricultural areas. Rill erosion can contribute vastly to the overall erosion rate. It is therefore crucial to identify areas prone to rill erosion in order to protect soil quality. Research on rainfall-runoff and subsequent sediment transport processes is often based on observing these processes at several scales, followed by a mathematical d ...
agriculturalwatersheds, etc ; agricultural soils; animal manures; atmospheric deposition; bioavailability; fractionation; human health; models; pollution; pollution control; regression analysis; research; risk; Show all 13 Subjects
Abstract:
... The bioavailable trace metals are closely related to environmental safety and human health, which might have different source characteristics from the total trace metals in soil. To identify such differences, 31 farmland soil samples were collected from a typical agricultural watershed in East China and analyzed for bioavailable trace metal sources by using chemical fractionation, linear regressio ...
... Understanding the origins of groundwater and its movement from hillslopes to valleys is critical for conserving water supplies, determining water-use policies and controlling pollution. These factors are also the keys for understanding the dominant processes in hydrological models. In this study, the sources of groundwater from hillslopes to valleys were explored by using a multiple-hillside obser ...
agriculturalwatersheds, etc ; agricultural land; cesium radioisotopes; forest land; grasslands; land cover; research; sediments; shrublands; soil; soil erosion; soil organic carbon; tillage; China; Show all 14 Subjects
Abstract:
... The dynamics of the soil organic carbon (SOC) pool and the mechanisms that underpin those dynamics are at the frontier of terrestrial carbon (C) cycling research. Soil erosion seriously affects the migration and redistribution of SOC, driving a critical part of the C cycle. In this study, soil samples were collected from a 14.69 m sediment profile formed between 1960 and 2017, which was located in ...
agriculturalwatersheds, etc ; Silurian period; anthropogenic activities; atmospheric precipitation; base flow; bedrock; cold season; groundwater; rivers; salinity; solutes; subsurface drainage; Illinois; Indiana; Ohio; Show all 15 Subjects
Abstract:
... Subsurface drainage modifications are a common practice in agricultural watersheds, especially in poorly drained soils of the American Midwest, yet our understanding of their impact on baseflow generation processes is incomplete. By extension, these same practices can make baseflow vulnerable to salinization. To address these knowledge gaps, a combined geochemical and multiple isotope approach was ...
agriculturalwatersheds, etc ; Bayesian theory; aquatic environment; eutrophication; hydrogeochemistry; land use; microorganisms; municipal wastewater; nitrates; nitrogen; pollution; rivers; sewage; soil; stable isotopes; swine; China; Show all 17 Subjects
Abstract:
... Excessive quantities of nitrates in the aquatic environment can cause eutrophication and raise water safety concerns. Therefore, identification of the sources of nitrate is crucial to mitigate nitrate pollution and for better management of the water resources. Here, the spatiotemporal variations and sources of nitrate were investigated by stable isotopes (δ¹⁵N and δ¹⁸O), hydrogeochemical variables ...
agriculturalwatersheds, etc ; case studies; digital elevation models; geostatistics; rivers; Poland; Show all 6 Subjects
Abstract:
... A digital elevation model (DEM) is an essential element of input data in the model research of watersheds. Recently, progress in measurement techniques has led to the availability of such data with high spatial resolution. Therefore, simplification of DEMs to shorten the time of their processing is a significant, but insufficiently investigated issue. This study, gradually and with various methods ...
agriculturalwatersheds, etc ; catenas; computer software; data collection; hydrodynamics; hydrologic models; land use planning; rain; runoff; seasonal variation; soil erosion; time series analysis; watershed management; Show all 13 Subjects
Abstract:
... The detrimental impacts of surface runoff and soil erosion, particularly in cultivated areas, call for the use of distributed runoff and soil erosion models with a view to supporting adapted catchment management strategies. However, runoff model parameterization remains challenging in agricultural catchments due to the high spatial and seasonal variability of soil properties. Data acquisition is d ...
agriculturalwatersheds, etc ; agricultural land; grain yield; lakes; nitrogen; nitrogen fertilizers; nutrient use efficiency; rhizosphere; soil water; spring wheat; water use efficiency; water utilization; China; Show all 13 Subjects
Abstract:
... Inappropriate irrigation and nitrogen application had caused low water and nitrogen use efficiency and severe NO₃⁻-N leaching in spring wheat field in the Wuliangshuhai lake watershed (WLSLW) of Northwest China. Thus, aimed at determining the rational irrigation and nitrogen fertilization for spring wheat in this area, field experiments were carried out in the 2019 and 2020 seasons to investigate ...
agriculturalwatersheds, etc ; data collection; gully erosion; inventories; land degradation; land management; neural networks; remote sensing; research; sediments; soil; soil conservation; streams; topography; water conservation; China; Show all 16 Subjects
Abstract:
... As a primary sediment source, gully erosion leads to severe land degradation and poses a threat to food and ecological security. Therefore, identification of susceptible areas is critical to the prevention and control of gully erosion. This study aimed to identify areas prone to gully erosion using four machine learning methods with derived topographic attributes. Eight topographic attributes (ele ...
agriculturalwatersheds, etc ; base flow; drought; groundwater; groundwater extraction; groundwater recharge; hydrologic cycle; irrigation scheduling; paddies; soil water; soil water content; subwatersheds; water supply; water table; Show all 14 Subjects
Abstract:
... Agricultural water demands are mainly dependent on the supply from groundwater withdrawals and the supply from agricultural reservoirs. To understand the water cycle of the agricultural catchment, it is necessary to consider the actual situation of the water cycle of paddy fields in catchments through accurate hydrological modeling. In this study, streamflow simulations were implemented in conside ...
agriculturalwatersheds, etc ; aquatic ecosystems; atmospheric precipitation; climate change; forests; runoff; temperature; Show all 7 Subjects
Abstract:
... The aims of this study are: i) to better understand the coupled interactions between land use changes, climate change and the aquatic ecosystem in a small agricultural catchment (<100 km²) with a long observation history (1963–2018) and a known land use history, and ii) to test available approaches to separate land use and climate change impacts on water resources in such a small catchment. The pr ...
agriculturalwatersheds, etc ; agricultural development; catenas; clay fraction; forest land; fractal dimensions; hydrology; land productivity; land use; mudstone; particle size; particle size distribution; soil quality; soil texture; Show all 14 Subjects
Abstract:
... The particle-size distribution (PSD) of soils is a basic physical attribute that affects edaphic hydrological, chemical, and biological properties as well as soil quality and land productivity. Purple soil, as an early weathering product of purple mudstone, is a valuable resource for agricultural development in southwestern China. However, little is known regarding PSDs of purple soil, especially ...
agriculturalwatersheds, etc ; Bayesian theory; income; pollutants; risk; risk reduction; wastewater; water management; Show all 8 Subjects
Abstract:
... Increasing amounts of wastewater are discharged to water bodies, with a risk of exceeding their capacity to cope with such loads. Nutrient discharge forms two types of risk, i.e., economic and excess effluent risks. In this study, a Bayesian dual risk aversion based stochastic programming (BDRSP) is proposed for selecting optimal effluent trading and multi-risk management schemes. The BDRSP framew ...
agriculturalwatersheds, etc ; Bacillariophyceae; agricultural runoff; arsenic; biofilm; biofuels; biomass; chromium; energy efficiency; feedstocks; lead; microalgae; microbiome; municipal wastewater; nitrogen; periphyton; phosphorus; pollution; remediation; slow-release fertilizers; solubilization; Show all 21 Subjects
Abstract:
... Untreated domestic wastewater and agricultural runoff are emerging as a potent cause of non-point source (NPS) pollutants which are a major threat to aquatic ecosystems. Periphyton biofilm-based technologies due to their high growth rate, energy efficiency and low input costs offer promising solutions for controlling nutrient pollution in agricultural systems. In this study we employed periphyton ...
agriculturalwatersheds, etc ; cadmium; land use; marine pollution; nickel; rivers; sediments; toxicity; Chesapeake Bay; Show all 9 Subjects
Abstract:
... Trace metals in sediments from the Chester River, a tidal tributary of the upper Chesapeake Bay with a predominantly rural, agricultural watershed, were investigated to better understand distributions and potential sources of metals. Sediments were analyzed for Al, Fe, Ni, Cr, Cu, Zn, As, Ag, Cd and organic C. Concentrations exceeded sediment toxicity guidelines in 44% of samples for Pb, and >20% ...
agriculturalwatersheds, etc ; agricultural land; automation; drainage; environment; soil erosion; temporal variation; turbidity; Nebraska; Show all 9 Subjects
Abstract:
... Quantifying temporal variability and fluxes within hydrologic catchments is critical to understanding the underlying chemical and physical processes leading to material transport. Measuring variability and fluxes requires sampling at time scales similar to the time scale of process occurrence. This demand has led to the development of automated sampling systems designed to sample at high frequenci ...