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nitrogen dioxide, etc ; air pollution; air quality; meteorology; particulates; traffic; urban areas; urbanization; China; Show all 9 Subjects
Abstract:
... Traditional air quality data have a spatial resolution of 1 km or above, making it challenging to resolve detailed air pollution exposure in complex urban areas. Combining urban morphology, dynamic traffic emission, regional and local meteorology, physicochemical transformations in air quality models using big data fusion technology, an ultra-fine resolution modeling system was developed to provid ...
nitrogen content, etc ; adsorbents; adsorption; carbon; carbon dioxide; carbonization; heat; polyacrylonitrile; porosity; temperature; China; Show all 11 Subjects
Abstract:
... In this report, nitrogen-doped porous carbons were synthesized from polyacrylonitrile fiber by a facile two-step synthesis process i.e. carbonization followed by KOH activation. Activation temperature and KOH/carbon ratio are two parameters to tune the porosity and surface chemical properties of sorbents. The as-obtained sorbents were carefully characterized. Special attention was paid concerning ...
... BACKGROUND: Cereal–legume intercropping systems are an environmentally friendly practice in sustainable agriculture. However, research on the interspecific interaction of nitrogen (N) between rice and aquatic legumes has rarely been undertaken. To address this issue, a pot experiment was conducted to investigate N utilization and the N interaction between rice and water mimosa (Neptunia oleracea L ...
... The demand for nitrogen (N) for crop production increased rapidly from the middle of the twentieth century and is predicted to at least double by 2050 to satisfy the on-going improvements in productivity of major food crops such as wheat, rice and maize that underpin the staple diet of most of the world’s population. The increased demand will need to be fulfilled by the two main sources of N suppl ...
... The globally dominant N₂‐fixing cyanobacteria Trichodesmium and Crocosphaera provide vital nitrogen supplies to subtropical and tropical oceans, but little is known about how they will be affected by long‐term ocean warming. We tested their thermal responses using experimental evolution methods during 2 years of selection at optimal (28°C), supra‐optimal (32°C) and suboptimal (22°C) temperatures. ...
nitrogen; nitrogen cycle; nitrogen retention, etc ; ammonia; estuaries; fauna; genes; habitats; microbiology; salinity; Show all 10 Subjects
Abstract:
... Estuaries are depositional environments prone to terrigenous mud sedimentation. While macrofaunal diversity and nitrogen retention are greatly affected by changes in sedimentary mud content, its impact on prokaryotic diversity and nitrogen cycling activity remains understudied. We characterized the composition of estuarine tidal flat prokaryotic communities spanning a habitat range from sandy to m ...
ammonium nitrogen; nitrate nitrogen; nitrogen, etc ; Weissella; beans; denitrification; genes; mineralization; nitrates; nitrification; nitrites; nitrogen fixation; nitrous oxide; pH; pollution; research; seed germination; temperature; total nitrogen; water solubility; Show all 20 Subjects
Abstract:
... This study explored how a thermophilic microbial agent altered nitrogen transformation, nitrogen functional genes, and bacterial communities during bean dregs composting with (T) and without (CK) a thermophilic microbial agent for 15 days. The results showed that the maximum temperature in T reached 73 °C and remained above 70 °C for 8 days, while that in CK was only 65 °C. The pH in T had essenti ...
nitrogen; nitrogen content; nitrogen fertilizers, etc ; cotton; fallow; grasses; legumes; micronaire; research; sandy soils; urea; Show all 11 Subjects
Abstract:
... Cover crops can affect nitrogen fertilization efficiency, soil nitrogen content, and cotton yield. However, the interaction effects of controlled-release nitrogen fertilizers, applied N rate, and cover crops on cotton growth, yield and fiber quality remains unknown, especially in sandy soils with low N content. Soil nitrogen and cotton growth, yield and fiber quality were evaluated as a function o ...
nitrogen; nitrogen fixation; nitrogen-fixing bacteria, etc ; ecosystems; energy; glucose; glutamic acid; mass spectrometry; microbial communities; peat; plant nitrogen content; primary productivity; Show all 12 Subjects
Abstract:
... Biological nitrogen fixation (BNF) performed by diazotrophs is vital to our understanding of ecosystem functions, as plant nitrogen (N) is commonly a limiting nutrient for primary productivity. However, significant limitations have remained in our knowledge of the controls and rates of this process, due to technical difficulties in directly quantifying nitrogen (N₂) fixation rates. To address this ...
nitrogen; nitrogen fertilizers; total nitrogen, etc ; agronomy; cauliflower; lettuce; nutrition; residual effects; soil; sustainable development; Italy; Show all 11 Subjects
Abstract:
... Up to 75% of nitrogen (N) taken up during cauliflowers production is allocated to leaves, which are left as crop residues after harvest. The inclusion of cauliflower, cultivated alone or intercropped with legumes, in rotation schemes, is a promising tool to optimize N availability to subsequent crops. This original study assessed, for the first time in South Tyrol, Italy, the effect of removal or ...
... While large inputs of synthetic nitrogen fertilizers enable our current rate of crop production and feed a growing global population, these fertilizers come at a heavy environmental cost. Driven by microbial processes, excess applied nitrogen is lost from agroecosystems as nitrate and nitrous oxide (N₂O) contaminate aquatic ecosystems and contribute to climate change. Interest in nitrogen-fixing m ...
... Fluctuating light and nitrogen (N) deficiency can occur synchronously under natural growth conditions. However, little is known about the photosynthetic regulation under fluctuating light in plants grown with N deficiency. In the present study, we examined the effect of N supply on the response of photosystem I (PSI) to fluctuating light in tomato. Plants grown under high N concentration (HN-plant ...
nitrogen; nitrogen fixation, etc ; Saccharum; crop models; sugarcane; Brazil; Show all 6 Subjects
Abstract:
... There are growing evidence that nitrogen (N) recommendation based on the expected yield concept developed by Stanford in 1973 lacks in agronomic principles, despite it widespread use worldwide. In Brazil, the main sugarcane producer worldwide, for example, a fixed N factor of 1 kg N per Mg⁻¹ of stalk is used. However, literature demonstrates that sugarcane responsiveness to N is much higher in san ...
nitrogen; nitrogen fertilizers; total nitrogen, etc ; ammonia; biochar; dicyandiamide; hydroquinone; nitrification inhibitors; nitrous oxide; nutrient use efficiency; pH; paddies; pollution; rice; urea nitrogen; urease; Show all 16 Subjects
Abstract:
... The effects of combined biochar and double inhibitor application on gaseous nitrogen (N; nitrous oxide [N₂O] and ammonia [NH₃]) emissions and N leaching in paddy soils remain unclear. We investigated the effects of biochar application at different rates and double inhibitor application (hydroquinone [HQ] and dicyandiamide [DCD]) on NH₃ and N₂O emissions, N leaching, as well as rice yield in a padd ...
nitrogen; nitrogen content; plant nitrogen content, etc ; environmental impact; mobile telephones; precision agriculture; research; satellites; tomatoes; Italy; Show all 10 Subjects
Abstract:
... Optimizing nitrogen (N) fertilization is increasingly becoming a key issue to maximize productivity and farmers’ income while reducing environmental impact of agricultural productions. Among the most sophisticated approaches to support variable rate N applications, a central role is played by frameworks that integrate satellite images and smart-scouting driven ground estimates of plant N content ( ...
leaf nitrogen content; nitrogen; nitrogen content, etc ; cotton; flowers; model validation; models; nutrition; reflectance; spectral analysis; China; Show all 11 Subjects
Abstract:
... As an important index of a plant’s N nutrition, leaf nitrogen content (LNC) can be quickly monitored in real time with hyperspectral information, which is helpful to guide the precise application of N in cotton leaves. In this study, taking cotton dripping in Xinjiang, China, as the object of study, five N application treatments (0, 120, 240, 360, 480 kg·ha-1) were set up, and the hyperspectral da ...
nitrogen; nitrogen content; nitrogen fertilizers, etc ; Zea mays; corn; environment; food security; nutrient use efficiency; nutrition; phytomass; Show all 10 Subjects
Abstract:
... Maize (Zea mays L.) breeding is continuously moving forward yield gains for many fields crops, increasing dependency to technology such as high input seed costs and high use of nitrogen (N) fertilizers. For this crop, breeding improvement led to concomitantly enhancing N recovery and uptake but following a similar ratio relative to the plant biomass (W) and nitrogen nutrition index (NNI, as actual ...
... 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 ( ...
nitrogen; nitrogen cycle; nitrogen fixation, etc ; carbon sequestration; ecosystems; forest litter; global change; legumes; mineral soils; prediction; Show all 10 Subjects
Abstract:
... The responses of forests to nitrogen (N) deposition largely depend on the fates of deposited N within the ecosystem. Nitrogen‐fixing legume trees widely occur in terrestrial forests, but the fates of deposited N in legume‐dominated forests remain unclear, which limit a global evaluation of N deposition impacts and feedbacks on carbon sequestration. Here, we performed the first ecosystem‐scale ¹⁵N ...
... Improper fertilization or excessive nitrogen input may cause serious environmental problems and affect soil health. This is particularly the case in saline agroecosystems, as soil salinization alters nitrogen cycling and contributes to substantial nitrogen losses. However, the impact of amendment materials on the combined processes of nitrogen transformation and migration in salt-affected soil has ...