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1. A Resurrected Scenario: Single Gain and Massive Loss of Nitrogen-Fixing Nodulation

Author:
van Velzen, Robin; Doyle, Jeff J.; Geurts, Rene
Source:
Trends in plant science 2019 v.24 no.1 pp. 49-57
ISSN:
1360-1385
Subject:
nitrogen; nitrogen fixation; nitrogen-fixing bacteria,   etc   ; genes; nitrogen-fixing plants; nodulation; root nodules; symbiosis;     Show all 8 Subjects
Abstract:
... Root nodule endosymbiosis with nitrogen-fixing bacteria provides plants with unlimited access to fixed nitrogen, but at a significant energetic cost. Nodulation is generally considered to have originated in parallel in different lineages, but this hypothesis downplays the genetic complexity of nodulation and requires independent recruitment of many common features across lineages. Recent phylogeno ...
DOI:
10.1016/j.tplants.2018.10.005

2. Nitrogen limitation affects the sinking property of Microcystis by promoting carbohydrate accumulation

Author:
Huang, Yingying; Hong, Jingjie; Liang, Chengyu; Li, Gengyang; Shen, Lin; Zhang, Haichun; Hu, Xiongxing; Chen, Xuechu
Source:
Chemosphere 2019 v.221 pp. 665-671
ISSN:
0045-6535
Subject:
nitrate nitrogen; nitrogen,   etc   ; Microcystis; autumn; carbohydrate content; carbohydrates; lakes; summer;     Show all 8 Subjects
Abstract:
... Nitrogen limitation has been proven to inhibit Microcystis proliferation, and the significant decline in Microcystis blooms in late summer or autumn has been considered to be related to the nitrogen depletion in water. Sinking loss is another factor that influences the dynamics of cyanobacteria in lakes. However, to date, it is still unclear how the sinking property of Microcystis responds to nitr ...
DOI:
10.1016/j.chemosphere.2019.01.080

3. How Does an Acidic Support Affect the Hydrotreatment of a Gas Oil with High Nitrogen Content?

Author:
Nguyen, Minh-Tuan; Pirngruber, Gerhard D.; Albrieux, Florian; Chainet, Fabien; Tayakout-Fayolle, Melaz; Geantet, Christophe
Source:
Energy & fuels 2019 v.33 no.2 pp. 1467-1472
ISSN:
1520-5029
Subject:
nitrogen; nitrogen content,   etc   ; adsorption; aluminum oxide; catalysts; fuel oils; pyrroles;     Show all 7 Subjects
Abstract:
... Two NiMo sulfide catalysts, supported on Al₂O₃ and silica–alumina, respectively, were compared in the hydrotreatment of a mixture of straight-run and coker gas oil. Experiments were conducted in a continuous fixed bed reactor, at 623–643 K and 5 MPa. The Al₂O₃-supported catalyst proved to be slightly more active in HDN and significantly more active in HDS than its silica–alumina analogue. The acti ...
DOI:
10.1021/acs.energyfuels.8b04116

4. Slow episodic movement driven by elevated pore-fluid pressures in shallow subaqueous slopes

Author:
Carey, J.M.; Crutchley, G.J.; Mountjoy, J.J.; Petley, D.N.; McSaveney, M.J.; Lyndsell, B.
Source:
Geomorphology 2019 v.329 pp. 99-107
ISSN:
0169-555X
Subject:
nitrogen,   etc   ; deformation; landslides; New Zealand;     Show all 4 Subjects
Abstract:
... Subaqueous slopes are susceptible to a broad range of failure mechanisms and deformation styles, many of which are not well characterised. We undertook novel laboratory-based testing using a Dynamic Back-Pressured Shearbox on samples collected from an area subject to ongoing slope failures, situated on the upper slope of New Zealand's Hikurangi Margin, to determine how increases in pore water and ...
DOI:
10.1016/j.geomorph.2018.12.034

5. Comparison of nitrogen deposition across different land use types in agro-pastoral catchments of western China and Mongolia

Author:
Lv, Jinling; Buerkert, Andreas; Benedict, Katherine B.; Liu, Guojun; Lv, Chaoyan; Liu, Xuejun
Source:
Atmospheric environment 2019 v.199 pp. 313-322
ISSN:
1352-2310
Subject:
ammonium nitrogen; nitrate nitrogen; nitrogen,   etc   ; ammonia; atmospheric chemistry; cropland; land use; nitrogen dioxide; pastures; watersheds; wet deposition; China; Mongolia;     Show all 13 Subjects
Abstract:
... Very few comparative studies on atmospheric dry and wet nitrogen (N) deposition have been conducted in agro-pastoral catchment areas. In an effort to fill this knowledge gap, three interconnected land use types (cropland, mountain pasture, and plain pasture) with six sampling sites (Chinese cropland (CC), Chinese mountain pasture (CM), Chinese plain pasture (CP) Mongolia cropland (MC), Mongolia mo ...
DOI:
10.1016/j.atmosenv.2018.11.021

6. An efficient way to enhance the total nitrogen removal efficiency of the Anammox process by S0-based short-cut autotrophic denitrification

Author:
Chen, Fangmin; Li, Xiang; Yuan, Yan; Huang, Yong
Source:
Journal of environmental sciences (China) 2019
ISSN:
1001-0742
Subject:
ammonium nitrogen; nitrate nitrogen; nitrogen dioxide,   etc   ; Thiobacillus; anaerobic ammonium oxidation; denitrification; microbial communities; nitrates; nitrifying bacteria; sulfur; total nitrogen; wastewater;     Show all 12 Subjects
Abstract:
... In order to reduce the amount of NO3−–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO2−–N in a single reactor, the preference of S0 for reacting with coexisting NO2−–N and NO3−–N in the sulfur autotrophic denitrifying (SADN) process and the coupling effect of short-cut SADN and the Anammox process were studied. The results showed that S0 ...
DOI:
10.1016/j.jes.2019.01.010

7. Effects of fertilizer nitrogen shortly before forcing through flowering on carbon-nitrogen composition and flowering of Phalaenopsis

Author:
Lin, Jen-An; Susilo, Hadi; Lei, Jia-Yun; Chang, Yao-Chien Alex
Source:
Scientia horticulturae 2019
ISSN:
0304-4238
Subject:
nitrogen; nitrogen content; nitrogen fertilizers,   etc   ; Phalaenopsis; cultivars; fertilizer rates; flowering; growth habit; hybrids; roots; vegetative growth;     Show all 11 Subjects
Abstract:
... Phalaenopsis (Phalaenopsis spp.) is an important orchid crop worldwide. Effect of fertilization on its growth has been much investigated, but studies about how nitrogen (N) fertilization affects flowering have sometimes yielded conflicting results. This study investigated how short-term N application affects the flowering of phalaenopsis, in relation to the size of stored N pool. Two cultivars wit ...
DOI:
10.1016/j.scienta.2019.02.006

8. Effective partial nitrification of ammonia in a fluidized bed bioreactor

Author:
Wang, Haolong; Kim, Mingu; Li, Kai; Shao, Yuanyuan; Zhu, Jesse; Nakhla, George
Source:
Environmental technology 2019 v.40 no.1 pp. 94-101
ISSN:
1479-487X
Subject:
ammonium nitrogen; nitrate nitrogen; nitrite nitrogen,   etc   ; ammonia; anaerobic ammonium oxidation; biofilm; bioreactors; dissolved oxygen; environmental technology; fluidized beds; nitrogen; nitrogen-fixing bacteria; pollution load; polyethylene; temperature;     Show all 15 Subjects
Abstract:
... A lab-scale fluidized bed bioreactor with high-density polyethylene as biofilm carrier media was operated to study partial nitrification (PN) performance with high ammonia concentrations. The system was run at nitrogen loading rates (NLRs) from 1.2 to 4.8 kg N/(m³ d) with empty bed contact time of 2.0 and 2.7 h and four different influent ammonia concentrations of 100, 200, 300 and 400 mg/L. Disso ...
DOI:
10.1080/09593330.2017.1380710

9. Nitrogen variations during the ice-on season in the eutrophic lakes

Author:
Yang, Tingting; Hei, Pengfei; Song, Jindong; Zhang, Jing; Zhu, Zhongfan; Zhang, Yingyuan; Yang, Jing; Liu, Chunlan; Jin, Jun; Quan, Jin
Source:
Environmental pollution 2019 v.247 pp. 1089-1099
ISSN:
0269-7491
Subject:
ammonium nitrogen; nitrogen; nitrogen cycle,   etc   ; case studies; eutrophication; ice; lakes; limnology; macrophytes; pollution; pollution control; quantitative analysis; sediments; winter; China;     Show all 15 Subjects
Abstract:
... Nitrogen accumulation in sediments, and the subsequent migration and transformations between sediment and the overlying water, plays an important role in the lake nitrogen cycle. However, knowledge of these processes are largely confined to ice-free seasons. Recent research under ice has mainly focused on the water eco-environmental effects during winter. Sediment N accumulation during the ice-on ...
DOI:
10.1016/j.envpol.2018.12.088

10. Side-by-side comparison of 15 pilot-scale conventional and intensified subsurface flow wetlands for treatment of domestic wastewater

Author:
Nivala, Jaime; Boog, Johannes; Headley, Tom; Aubron, Thomas; Wallace, Scott; Brix, Hans; Mothes, Sibylle; van Afferden, Manfred; Müller, Roland A.
Source:
The Science of the total environment 2019 v.658 pp. 1500-1513
ISSN:
0048-9697
Subject:
ammonium nitrogen; nitrate nitrogen; nitrite nitrogen,   etc   ; Escherichia coli; Phragmites; aeration; gravel; municipal wastewater; sand; subsurface flow; wetlands;     Show all 11 Subjects
Abstract:
... This study reports a systematic assessment of treatment efficacy for 15 pilot-scale subsurface flow constructed wetlands of different designs for CBOD5, TSS, TOC, TN, NH4-N, NO3-N, NO2-N, and E. coli over the course of one year in an outdoor study to evaluate the effects of design and plants. The systems consisted of a range of designs: horizontal flow (HF) with 50 and 25 cm depth, unsaturated ver ...
DOI:
10.1016/j.scitotenv.2018.12.165

11. Comprehensive analysis of nitrogen distributions and ammonia nitrogen release fluxes in the sediments of Baiyangdian Lake, China

Author:
Zhu, Yaoyao; Jin, Xin; Tang, Wenzhong; Meng, Xin; Shan, Baoqing
Source:
Journal of environmental sciences (China) 2019 v.76 pp. 319-328
ISSN:
1001-0742
Subject:
ammonium nitrogen; nitrate nitrogen; nitrogen,   etc   ; United States Environmental Protection Agency; ammonia; benthic organisms; economic development; lakes; pollution; sediments; China;     Show all 11 Subjects
Abstract:
... The condition of Baiyangdian Lake (BYDL) will improve as the Xiongan New Area evolves and fulfills its role of easing overcrowding and supporting economic growth. Water and sediment samples from BYDL were analyzed to provide information on nitrogen (N) contamination in BYDL. The mean ammonium N (NH4+-N), nitrate N, and total N concentrations in the water samples were 0.36, 0.12, and 2.22 mg/L, res ...
DOI:
10.1016/j.jes.2018.05.024

12. Denitrification and the controlling factors in Yunnan Plateau Lakes (China): Exploring the role of enhanced internal nitrogen cycling by algal blooms

Author:
Wu, Sifeng; Wu, Zhen; Liang, Zhongyao; Liu, Yong; Wang, Yilin
Source:
Journal of environmental sciences (China) 2019 v.76 pp. 349-358
ISSN:
1001-0742
Subject:
nitrogen; nitrogen content; nitrogen cycle,   etc   ; algal blooms; ammonia; denitrification; denitrifying bacteria; freshwater ecosystems; lakes; metabolism; nitrates; nitrification; nutrients; sediments; China;     Show all 15 Subjects
Abstract:
... Denitrification plays an important role in nitrogen (N) removal in freshwater ecosystems. This internal process regulates the fluctuations of N concentration, especially for lakes with high nutrients concentrations and long residence time. Lakes in Yunnan plateau (southwestern China) provide typical cases, while studies in this region have been rare. Therefore, we studied denitrification of two la ...
DOI:
10.1016/j.jes.2018.05.028

13. Nitrogen removal in response to the varying C/N ratios in subsurface flow constructed wetland microcosms with biochar addition

Author:
Zhou, Xu; Wu, Shubiao; Wang, Ruigang; Wu, Haiming
Source:
Environmental science and pollution research international 2019 v.26 no.4 pp. 3382-3391
ISSN:
0944-1344
Subject:
ammonium nitrogen; carbon nitrogen ratio; nitrogen,   etc   ; adsorption; biochar; chemical oxygen demand; municipal wastewater; nitrification; oxygen; pollution control; subsurface flow; wetlands;     Show all 12 Subjects
Abstract:
... Biochar as a substrate has great potential to promote pollutant removal efficiency in subsurface flow constructed wetlands (SSFCWs). However, information about the effect of different influent C/N ratios on treatment efficiency in SSFCWs with biochar is still scarce. In this study, SSFCW microcosms added with and without biochar were performed to investigate comparatively nitrogen removal in respo ...
DOI:
10.1007/s11356-018-3871-4

14. Do N‐fixing legumes promote neighbouring diversity in the tropics?

Author:
Xu, Han; Detto, Matteo; Li, Yanpeng; Li, Yide; He, Fangliang; Fang, Suqin
Source:
Thejournal of ecology 2019 v.107 no.1 pp. 229-239
ISSN:
0022-0477
Subject:
nitrogen; nitrogen fixation; nitrogen-fixing plants,   etc   ; ecosystems; habitat preferences; habitats; leaves; legumes; metabolism; soil; tropical rain forests; tropics; China;     Show all 13 Subjects
Abstract:
... 1. Although nitrogen‐fixing plants play a crucial role in maintaining high ecosystem productivity, their effects on forest diversity are greatly debated. Legumes can reduce local diversity because of the fertilization effect; however, they can also facilitate species coexistence through complementary resource utilization. 2. In natural forests, nitrogen requirements and biological nitrogen fixatio ...
DOI:
10.1111/1365-2745.13017

15. Impact of carbon to nitrogen ratio on the performance of aerobic granular reactor and microbial population dynamics during aerobic sludge granulation

Author:
Wang, Xiaochun; Chen, Zhonglin; Shen, Jimin; Zhao, Xia; Kang, Jing
Source:
Bioresource technology 2019 v.271 pp. 258-265
ISSN:
0960-8524
Subject:
ammonium nitrogen; carbon nitrogen ratio; nitrogen,   etc   ; carbon; genes; microbial communities; microorganisms; pollution control; population dynamics; ribosomal DNA; sludge;     Show all 11 Subjects
Abstract:
... Carbon to nitrogen (C/N) ratio is one of the most important factor affecting aerobic granular sludge (AGS) growth and pollutant removal in aerobic granular sludge sequencing batch reactor (AGSBR). For stability of sludge granulation process, AGSs were domesticated in five sequence batch reactors (SBRs) with different C/N ratios (6, 7, 8, 9, and 10), which the ammonia nitrogen concentration of infl ...
DOI:
10.1016/j.biortech.2018.09.119

16. Intermittent operating characteristics of an ecological soil system with two-stage water distribution for wastewater treatment

Author:
Wu, Suqing; Wang, Hong; Fan, Chunzhen; Zhou, Weili; He, Shengbing; Zheng, Xiangyong
Source:
Chemosphere 2019 v.215 pp. 8-14
ISSN:
0045-6535
Subject:
ammonium nitrogen; nitrogen; total nitrogen,   etc   ; chemical oxygen demand; denitrification; sewage treatment; total phosphorus; wastewater; wastewater treatment; water distribution; China;     Show all 11 Subjects
Abstract:
... Ecological soil systems (ESSs) are usually used to remove nitrogen from wastewater. Due to the poor denitrification performance of traditional ecological soil systems (ESSs), this study proposes a two-stage water distribution system to improve the nitrogen removal. The effects of different distribution ratios on the system treatment effect were studied in an intermittent operation mode. After dete ...
DOI:
10.1016/j.chemosphere.2018.10.014

17. Legume nodulation: The host controls the party

Author:
Ferguson, Brett J.; Mens, Céline; Hastwell, April H.; Zhang, Mengbai; Su, Huanan; Jones, Candice H.; Chu, Xitong; Gresshoff, Peter M.
Source:
Plant, cell and environment 2019 v.42 no.1 pp. 41-51
ISSN:
0140-7791
Subject:
nitrogen; nitrogen fertilizers; nitrogen fixation,   etc   ; bacteria; crops; cultivars; food production; food security; genomics; legumes; models; nodulation; sustainable agriculture; symbiosis;     Show all 14 Subjects
Abstract:
... Global demand to increase food production and simultaneously reduce synthetic nitrogen fertilizer inputs in agriculture are underpinning the need to intensify the use of legume crops. The symbiotic relationship that legume plants establish with nitrogen‐fixing rhizobia bacteria is central to their advantage. This plant–microbe interaction results in newly developed root organs, called nodules, whe ...
DOI:
10.1111/pce.13348

18. Effect of Fe2+ addition on chemical oxygen demand and nitrogen removal in horizontal subsurface flow constructed wetlands

Author:
Zhang, Yan; Liu, Xuelan; Fu, Chunyan; Li, Xinhua; Yan, Baixing; Shi, Tianhong
Source:
Chemosphere 2019 v.220 pp. 259-265
ISSN:
0045-6535
Subject:
ammonium nitrogen; nitrate nitrogen; nitrogen,   etc   ; Phragmites australis; chemical oxygen demand; denitrification; iron; microorganisms; organic carbon; pH; subsurface flow; total nitrogen; wetlands;     Show all 13 Subjects
Abstract:
... Horizontal subsurface flow constructed wetlands (CWs) planted with Phragmites australis were set up to analyze the effect of external ferrous iron (Fe2+) addition on chemical oxygen demand (COD) and nitrogen removal. The results showed that external Fe2+ addition has no significant effect on COD removal, while the COD removal efficiencies in CWs with Fe2+ addition were slightly lower than those in ...
DOI:
10.1016/j.chemosphere.2018.12.144

19. Biochar additions alter phosphorus and nitrogen availability in agricultural ecosystems: A meta-analysis

Author:
Gao, Si; DeLuca, Thomas H.; Cleveland, Cory C.
Source:
The Science of the total environment 2019 v.654 pp. 463-472
ISSN:
0048-9697
Subject:
ammonium nitrogen; carbon nitrogen ratio; nitrate nitrogen,   etc   ; agroecosystems; biochar; carbon; feedstocks; meta-analysis; microbial biomass; nitrogen; organic fertilizers; phosphorus; soil amendments; soil pH; soil types; temperature;     Show all 16 Subjects
Abstract:
... Biochar is a carbon (C) rich product of thermochemical conversion of organic material that is used as a soil amendment due to its resistance to decomposition and its influence on nutrient dynamics; however, individual studies on biochar effects on phosphorus (P) and nitrogen (N) have proven inconsistent. Herein, we performed a meta-analysis of 124 published studies to evaluate the influence of bio ...
DOI:
10.1016/j.scitotenv.2018.11.124

20. Integrated reclamation of saline soil nitrogen transformation in the hyphosphere by earthworms and arbuscular mycorrhizal fungus

Author:
Zhang, Wenwen; Wang, Chong; Liu, Mengli; Yu, Yingchai
Source:
Applied soil ecology 2019 v.135 pp. 137-146
ISSN:
0929-1393
Subject:
ammonium nitrogen; microbial nitrogen; nitrate nitrogen,   etc   ; earthworms; food production; genes; genetic markers; hyphae; mycorrhizal fungi; nitrogen cycle; saline soils; salt concentration; soil organic carbon; soil salinization; soil salts;     Show all 15 Subjects
Abstract:
... Soil salinization greatly alters nitrogen cycling and threatens the sustainable productivity of food production areas worldwide. A two-compartment microcosm was used to investigate the integrated effects of arbuscular mycorrhizal fungi (AMF) hyphae and earthworms on nitrogen transformation at different incubation times in saline soil. The treatments were designed with or without hyphae and with or ...
DOI:
10.1016/j.apsoil.2018.12.005