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... The environmental behavior of arsenic (As) is commonly affected by the biogeochemical processes of iron (Fe) and nitrogen (N). In this study, field experiments were conducted to explore As uptake in rice and As translation and distribution in As-contaminated iron-rich paddy soils after applying different forms of N fertilizers, including urea (CO(NH₂)₂), ammonium bicarbonate (NH₄HCO₃), nitrate of ...
nitratenitrogen, etc ; ammonium nitrogen; automation; carbon dioxide; climate change; plant litter; rain; rhizodeposition; snow; soil ecology; soil respiration; soil temperature; soil water; water content; China; Show all 15 Subjects
Abstract:
... Soil respiration, the second largest CO₂ flux in terrestrial ecosystems, involves the microbial respiration of litter from aboveground sources, belowground litter and root respiration, from rhizodeposition. In the subtropical forests of the Ailao Mountain, a chamber with automated CO₂ efflux was set up with two treatments: a control treatment with litterfall to measure the total soil respiration ( ...
... Recent increases in soil-borne plant disease have limited further expansion of some crops produced in protected agriculture. Soil fumigation effectively minimizes the impact of soil pathogens causing many diseases. We provide the first report of the efficacy of the Chinese fungicide ethylicin as a soil fumigant against the plant pathogens such as Fusarium spp. and Phytophthora spp., and against th ...
nitratenitrogen, etc ; catalase; compound fertilizers; crop yield; deficit irrigation; enzyme activity; fertilizer rates; fruit weight; fruits; irrigation rates; mangoes; maturity stage; microirrigation; nutrient content; phosphorus; potassium; soil; soil enzymes; soil nutrients; soil quality; urease; water conservation; water solubility; water use efficiency; China; Show all 25 Subjects
Abstract:
... Reasonable irrigation and fertilization practices can not only improve soil quality, but also increase crop yield, and water-fertilizer use efficiency. However, it is still unclear that the micro-irrigation and fertilization mode is conducive to improving the soil comprehensive environment, the mango yield and water-fertilizer use efficiency in the dry-hot region. The effects of regulated deficit ...
... The recirculating pond aquaculture system (RPAS) consisted of culture ponds, a purification pond, inflow ditch, outflow pipe, ecological ditch, and electrically driven pump. The performance of RPAS on grass carp (Ctenopharyngodon idellus) was explored in this study. In both the RPAS and the traditional pond aquaculture system (TPAS), water quality, fish growth performance, muscle quality, and tiss ...
nitratenitrogen, etc ; aquifers; chlorides; denitrification; groundwater; lithology; models; sustainable development; Ghana; Show all 9 Subjects
Abstract:
... The identification of the chemical status of groundwater is a prerequisite for the sustainable management and development of groundwater resources. A better assessment of the chemical status of the groundwater requires the knowledge and understanding of the natural background concentrations to establish threshold values of chemical pollutants in groundwater. The aim of this study is to estimate th ...
nitratenitrogen, etc ; ammonium nitrogen; biogeochemistry; climate change; environment; rain; reactive phosphorus; rivers; Show all 8 Subjects
Abstract:
... Climate change and anthropogenic water demand have increased the frequency and duration of drying periods across rivers and streams worldwide. However, the biogeochemical processes during the water return in desiccated riverbeds are still unclear. Drying is a complex and diverse process and biogeochemical implications upon flow resumption may depend on attributes of the drying and river sediment c ...
nitratenitrogen, etc ; alpine grasslands; ammonium nitrogen; botany; carbon sequestration; field experimentation; nitrogen; China; Show all 8 Subjects
Abstract:
... The fates and redistribution of deposited nitrogen (N) determine the influence on N cycling in terrestrial ecosystems. However, the different fates between deposited nitrate nitrogen (NO₃⁻) and ammonium nitrogen (NH₄⁺) as well as the amount of deposited N retained in ecosystems are still not fully understood. We conducted a field experiment to investigate the fates of deposited NO₃⁻ and NH₄⁺ by ap ...
nitratenitrogen, etc ; base flow; dissolved organic carbon; evapotranspiration; hysteresis; solutes; summer; watersheds; Colorado; Show all 9 Subjects
Abstract:
... Concentration‐discharge (C‐Q) relationships can provide insight into how catchments store and transport solutes, but analysis is often limited to long‐term behaviour assessed from infrequent grab samples. Increasing availability of high‐frequency sensor data has shown that C‐Q relationships can vary substantially across temporal scales, and in response to different hydrologic drivers. Here, we pre ...
nitratenitrogen, etc ; barley straw; carbon; infrastructure; summer; vegetation; water quality; wetland plants; wetlands; Show all 9 Subjects
Abstract:
... Floating treatment wetlands are an innovative wetland design to passively improve water quality and remove pollutants from reservoirs with limited infrastructure modification or construction as compared to traditional treatment wetlands. However, design recommendations remain limited. Therefore, the objectives of this study were: 1. Determine nitrate-N removal rates in two floating treatment wetla ...
nitratenitrogen, etc ; altitude; carbon dioxide; nitrogen; psychological stress; soil; total nitrogen; Himalayan region; India; Show all 9 Subjects
Abstract:
... Nitrogen is an essential macronutrient necessary for a variety of physiological processes in plants, available in numerous fractions, each of which has direct relationship with the area’s environmental circumstances since it causes the formation of these fractions. Seasonal and altitudinal variations in nitrogen concentration were found to have a significant impact. The soil of the western Himalay ...
nitratenitrogen, etc ; agronomy; field experimentation; nitrogen; nutrition; phosphorus; phytoaccumulation; soil; soil minerals; winter wheat; zinc; Show all 11 Subjects
Abstract:
... Nitrogen (N) fertilization increases zinc (Zn) acquisition in cereal crops. However, little is known about the effects of N fertilization on grain Zn concentration in relation to availability of soil N and phosphorous (P) and root mycorrhizal colonization. The present study used a 12-year location-fixed field experiment with winter wheat grown at five N fertilization rates (0, 80, 160, 240 and 320 ...
nitratenitrogen, etc ; alloys; capacitance; electrochemistry; electrodes; electrolytes; foams; nitrates; nitrogen; particle size; reaction kinetics; wastewater; Show all 12 Subjects
Abstract:
... It still remains a hotspot and great challenge to efficiently remove the nitrate nitrogen from high salt wastewater. Herein, a novel three dimensional porous bimetallic copper-nickel alloy electrode was fabricated with Ni foam (NiF) as substrate. The physicochemical and electrochemical characterization results showed Cu–Ni/NiF electrode possessed the smaller particle size (0.3–1.0 μm) and electrod ...
... In this study, nitrogen transformation of chicken manure (CM) and cattle dung (CD) during composting was analyzed and its related functional keystones were identified. The results showed that chicken manure showed more severe nitrogen conversion during composting. The main N conversion factors in cattle dung were nitrite nitrogen (NO₂–-N) and ammonium nitrogen (NH₄⁺-N), while the main N conversion ...
... For investigating the microbial community, interspecific interaction and nitrogen metabolism during the transform process from heterotrophic to synergistic and autotrophic denitrification, a filter was built, and carbon source and sulfur concentration were changed to release the transformation process. The results demonstrated that the transformation process was feasible to keep nitrate nitrogen ( ...
... PURPOSE: Plants growing in the soils of karst forests associate with arbuscular mycorrhizae (AM) or ectomycorrhizae (ECM) to acquire nutrients. We researched how these different mycorrhizal associations affect rhizosphere soil nutrient economy in these calcareous soils. METHODS: Bulk and rhizosphere soils were sampled beneath 25 AM and 9 ECM plants growing in primary forests at the Puding Karst Cr ...
nitratenitrogen, etc ; Clarias gariepinus; Lactuca sativa var. capitata; aquaponics; catfish; clay; filtration; hydroponics; nitrogen; phosphorus; wastewater; Show all 11 Subjects
Abstract:
... The aquaponic recirculation system (ARS) combined aquaculture and hydroponic systems in a mutually beneficial environment. In this study, African catfish, Clarias gariepinus with Butterhead lettuce, Lactuca sativa were cultivated to evaluate gravel-based media and lightweight extended clay aggregate (LECA) as a physical filtration in the nutrient's removal. The performance of both tested growing m ...
nitratenitrogen, etc ; biomass; conifers; fine roots; forests; hardwood; leaves; nitrogen; soil water; spatial distribution; water purification; Show all 11 Subjects
Abstract:
... In forest ecosystems, understanding the relationship between the vertical distribution of fine roots and residual soil nitrogen is essential for clarifying the diversity–productivity–water purification relationship. Vertical distributions of fine‐root biomass (FRB) and concentrations of nitrate‐nitrogen (NO₃‐N) in soil water were investigated in a conifer plantation with three thinning intensities ...
nitratenitrogen, etc ; ammonium nitrogen; aquaculture; dissolved oxygen; groundwater; models; pH; prediction; support vector machines; water quality; Show all 10 Subjects
Abstract:
... Good water quality is important for normal production processes in industrial aquaculture. However, in situ or real-time monitoring is generally not available for many aquacultural systems due to relatively high monitoring costs. Therefore, it is necessary to predict water quality parameters in industrial aquaculture systems to obtain useful information for managing production activities. This stu ...
nitratenitrogen, etc ; bioreactors; denitrification; environment; nitrogen; rain; subsurface drainage; temperature; water quality; wood chips; South Dakota; Show all 11 Subjects
Abstract:
... Edge-of-field practices such as denitrifying woodchip bioreactors can be used to improve the water quality of agricultural effluents. This study evaluated the effectiveness of four field-scale woodchip bioreactors in removing nitrate‑nitrogen (nitrate-N) from subsurface drainage in eastern South Dakota. Four woodchip bioreactors were installed and monitored between 2014 and 2016 near Arlington, Ba ...