The impact of the organic carbon to nitrate ratio (C/N ratio) on mixotrophic denitrification rate has been scarcely studied. Thus, this work aims to investigate the effect of the C/N ratio on the mixotrophic denitrification when methanol is used as a source of organic matter and elemental sulfur as an electron donor for autotrophic denitrification. For this, two initial concentrations of NO-N (50 and 25 mg/L) at a stoichiometric ratio of S/N, and four initial C/N ratios (0, 0.6, 1.2, and 1.9 mg CHOH/mg NO -N) were used at 25 (±2) °C. The results showed that when using a C/N ratio of 0.6, the highest total nitrogen removal was obtained and the accumulation of nitrites was reduced, compared to an autotrophic system. The most significant contribution to nitrate consumption was through autotrophic denitrification (AuDeN) for a C/N ratio of 0.6 and 1.2, while for C/N = 1.9 the most significant contribution of nitrate consumption was through heterotrophic denitrification (HD). Finally, organic supplementation (methanol) served to increase the specific nitrate removal rate at high and low initial concentrations of substrate. Therefore, the best C/N ratio was 0.6 since it allowed for increasing the removal efficiency and the denitrification rate.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1080/10934529.2021.2004839 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Divergent responses of plant multi-element coupling to nitrogen and phosphorus addition in a meadow steppe.
BMC Plant Biol
January 2025
Institute of Grassland Science, School of Life Sciences, Key Laboratory of Vegetation Ecology, Ministry of Education, Northeast Normal University, Changchun, China.
The intricate biogeochemical cycling of multiple elements plays a pivotal role in upholding a myriad of ecosystem functions. However, our understanding of elemental stoichiometry and coupling in response to global changes remains primarily limited to plant carbon: nitrogen: phosphorus (C: N: P). Here, we assessed the responses of 11 elements in plants from different functional groups to global changes.
View Article and Find Full Text PDFHow do trees fail in intraspecific competition? A test for the roles of non-structural carbohydrates and stoichiometries in Pinus massoniana.
Plant Physiol Biochem
January 2025
College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, 310058, China. Electronic address:
Competition is ubiquitous and an important driver of tree mortality. Non-structural carbohydrates (NSCs, including soluble sugars and starch) and C-N-P stoichiometries are affected by the competitive status of trees and, in turn, physiologically determine tree growth and survival in competition. However, the physiological mechanisms behind tree mortality caused by intraspecific competition remain unclear.
View Article and Find Full Text PDFExperimental Investigation on Macroscopic and Microscopic Mechanical Properties of Geopolymer-Stabilized Macadam.
Materials (Basel)
January 2025
School of Civil Engineering, Central South University, Changsha 410075, China.
Geopolymer, as a promising inorganic binding material, holds potential for use in constructing base layers for highway pavements. This study aims to evaluate the mechanical properties of geopolymer-stabilized macadam (GSM) at both the micro- and macro-scale by a series of tests, demonstrating that high-Ca GSM is a high-quality material for pavement base layers. The results demonstrated that GSM exhibits outstanding mechanical and fatigue properties, significantly surpassing those of cement-stabilized macadam (CSM).
View Article and Find Full Text PDFExploring the Potential of sp. SW4-6 as a Probiotic for Enhancing Water Quality in Aquaculture.
Microorganisms
December 2024
Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung 912, Taiwan.
Aquaculture, a vital industry supplying a significant portion of the world's seafood, faces challenges such as the deterioration of the aquaculture environment. The objective of this study was to isolate and identify microorganisms with the capacity to eliminate nitrite in water from shrimp ponds and evaluate their potential as probiotics to improve water quality. Additionally, the study also determines the ideal conditions for the probiotic to effectively reduce nitrite-N and ammonia-N.
View Article and Find Full Text PDFCereal-legume intercropping stimulates straw decomposition and promotes soil organic carbon stability.
Sci China Life Sci
January 2025
State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou, 730000, China.
Increasing carbon (C) sequestration and stability in agricultural soils is a key strategy to mitigate climate change towards C neutrality. Crop diversification is an initiative to increase C sequestration in fields, but it is unclear how legume-based crop diversification impacts the functional components of soil organic carbon (SOC) in dryland, including the formation and transformation of particulate organic carbon (POC) and mineral-associated organic carbon (MAOC). We investigated the decomposition of straw residues, the fate of photosynthesized C, as well as the formation of MAOC and POC fractions using an in situC labeling technique in the soybean-wheat intercropping, soybean-maize intercropping and their respective monocropping systems, with and without cover crops.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!