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Effects of Non-protein Nitrogen Supplement on Growth Performance of Graze Cattle
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作者 LI Ying-guang YANG De-cheng +5 位作者 LI Jun-ping GUAN Chao ZHANG Yuan-qing YANG Zhong ZHANGXi-zhong YANG Xiao-min 《Animal Husbandry and Feed Science》 CAS 2011年第6期5-6,共2页
[Objective] The experiment was conducted to investigate the growth performance of graze cattle fed on non-protein nitrogen (NPN) supplement. [ Method] The experiment was conducted in late spring and early summer bef... [Objective] The experiment was conducted to investigate the growth performance of graze cattle fed on non-protein nitrogen (NPN) supplement. [ Method] The experiment was conducted in late spring and early summer before grazing. Thirty Chinese SimmentaI-Taihang taxa bulls at the age of 9-10 months weighing 150-170 kg were divided into the control group, experimental group 1 and experimental group 2, 10 in each group, Each cattle in the experimental group 1 fed on the basal diet supplemented 1.0 kg cornmeal every day. Each cattle in the experimental group 2 fed on the basal diet supplemented 1.0 kg cornmeal and 0.25 kg NPN supplement every day. Those in the control group were fed on the basal di- et. The experiment was performed for 100 d. [Result] The average daily gain of the experimental group I was 217 g larger than that of the control group, while the average daily gain of the experimental group 2 was 429 g larger than that of the control group. The differences in the average daily gain were significant between the three groups. [ Conclusion ] The growth performance of cattle grazed in northern slopes was obviously improved by supplementing a small amount of concentrate in feed. The improvement was more remarkable if a small amount of NPN supplement was also added in feed. 展开更多
关键词 Taihang taxa bull non-protein nitrogen supplement Graze Supplementary feeding Weight gain
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Production Technology and Application of Slow-Release Non-protein Nitrogen Extruded Feed Additive
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作者 XIE Hong-wei SUN Dong-bo +3 位作者 LIU Bo-chen DING Lan-feng BAO Yu-qing SHI Jian-chun 《Animal Husbandry and Feed Science》 CAS 2011年第3期7-8,12,共3页
Slow-release non-protein nitrogen feed has a large market demand. It has a long research history, but its production technology needs further improvement in order to realize the industrial production of slow-release n... Slow-release non-protein nitrogen feed has a large market demand. It has a long research history, but its production technology needs further improvement in order to realize the industrial production of slow-release non-protein nitrogen extruded feed. By designing the best formula and using chelating and emulsifying process, the slow-release non-protein nitrogen extruded feed additives were produced. This product increases milk yield and improves milk quality, thus increasing economic efficiency. 展开更多
关键词 Slow release non-protein nitrogen Feed additives RUMINANTS
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Increased dependence on nitrogen-fixation of a native legume in competition with an invasive plant 被引量:1
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作者 Meixu Han Haiyang Zhang +12 位作者 Mingchao Liu Jinqi Tang Xiaocheng Guo Weizheng Ren Yong Zhao Qingpei Yang Binglin Guo Qinwen Han Yulong Feng Zhipei Feng Honghui Wu Xitian Yang Deliang Kong 《Plant Diversity》 SCIE CAS CSCD 2024年第4期510-518,共9页
Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native ... Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native plants interact with the quantity and activity of nutrient-acquisition agents.Here a pot experiment was conducted with monoculture and mixed plantings of an invasive plant,Xanthium strumarium,and a common native legume,Glycine max.We measured traits related to root and nodule quantity and activity and mycorrhizal colonization.Compared to the monoculture,fine root quantity(biomass,surface area)and activity(root nitrogen(N)concentration,acid phosphatase activity)of G.max decreased in mixed plantings;nodule quantity(biomass)decreased by 45%,while nodule activity in Nfixing via rhizobium increased by 106%;mycorrhizal colonization was unaffected.Contribution of N fixation to leaf N content in G.max increased in the mixed plantings,and this increase was attributed to a decrease in the rhizosphere soil N of G.max in the mixed plantings.Increased root quantity and activity,along with a higher mycorrhizal association was observed in X.strumarium in the mixed compared to monoculture.Together,the invasive plant did not directly scavenge N from nodule-fixed N,but rather depleted the rhizosphere soil N of the legume,thereby stimulating the activity of N-fixation and increasing the dependence of the native legume on this N source.The quantity-activity framework holds promise for future studies on how native legumes respond to alien plant invasions. 展开更多
关键词 Mycorrhizal strategy nitrogen depletion Plant invasion Root nutrient acquisition strategy Symbiotic nitrogen fixation
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Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods 被引量:1
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作者 Yongjian Chen Lan Dai +7 位作者 Siren Cheng Yong Ren Huizi Deng Xinyi Wang Yuzhan Li Xiangru Tang Zaiman Wang Zhaowen Mo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期511-535,共25页
Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and frag... Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant rice.However,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain unknown.The field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice cultivars.Compared with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP contents.The rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization treatments.The N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response parameters.The key parameters for the HRY and 2-AP content were assessed by redundancy analysis.Furthermore,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant rice.Moreover,high N and Si accumulation directly promoted the 2-AP content or affected the antioxidant response parameters and indirectly regulated 2-AP synthesis.The interactions of the MT method with the N-Si fertilization treatments varied in the fragrant rice cultivars in terms of the HRY and 2-AP content,whereas the MD method was beneficial to the 2-AP content in both fragrant rice cultivars under the N-Si fertilization treatments. 展开更多
关键词 fragrant rice 2-AP content head rice yield mechanical planting nitrogen silicon
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Identification of the lysine and histidine transporter family in Camellia sinensis and the characterizations in nitrogen utilization 被引量:1
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作者 Wei Huang Danni Ma +9 位作者 Fawad Zaman Xulei Hao Li Xia E Zhang Pu Wang Mingle Wang Fei Guo Yu Wang Dejiang Ni Hua Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期273-287,共15页
In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen wit... In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen with a relatively high level of amino acids.However,systematic identification and molecular characterization of the LHT gene family has rarely been reported in tea plants.In this study,22 CsLHTs were identified from the‘Shuchazao’genome and classified into two groups.The modeled three-dimensional structure and the conserved domains presented a high similarity among the LHTs proteins.Moreover,it was predicted that a few genes were conserved through the analysis of the physiochemical characters,structures and cis-elements in promoters.The expression patterns in tea plants revealed that CsLHT7 was mainly expressed in the roots,and CsLHT4 and CsLHT11 exhibited relatively high expression in both the roots and leaves.Moreover,the expression of all three genes could be induced by organic nitrogen.Additionally,heterogeneous expression of CsLHT4,CsLHT7 and CsLHT11 in Arabidopsis thaliana decreased the aerial parts biomass compared with that in WT plants while significantly increased the rosette biomass only for CsLHT11transgenic plants versus WT plants.Overall,our results provide fundamental information about CsLHTs and potential genes in N utilization for further analysis in tea plants. 展开更多
关键词 Camellia sinensis nitrogen Lysine and histidine transporter(LHT)family
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Composition Engineering Opens an Avenue Toward Efficient and Sustainable Nitrogen Fixation 被引量:1
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作者 Xiaolin Wang Liming Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期313-325,共13页
In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active ... In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active sites as exemplified by diatomic metals anchored graphdiyne via the combination of hierarchical high-throughput screening,first-principles calculations,and molecular dynamics simulations.Totally 43 highly efficient catalysts feature ultralow onset potentials(|U_(onset)|≤0.40 V)with Rh-Hf and Rh-Ta showing negligible onset potentials of 0 and-0.04 V,respectively.Extremely high catalytic activities of Rh-Hf and Rh-Ta can be ascribed to the synergistic effects.When forming heteronuclears,the combinations of relatively weak(such as Rh)and relatively strong(such as Hf or Ta)components usually lead to the optimal strengths of adsorption Gibbs free energies of reaction intermediates.The origin can be ascribed to the mediate d-band centers of Rh-Hf and Rh-Ta,which lead to the optimal adsorption strengths of intermediates,thereby bringing the high catalytic activities.Our work provides a new and general strategy toward the architecture of highly efficient catalysts not only for electrocatalytic nitrogen reduction reaction(eNRR)but also for other important reactions.We expect that our work will boost both experimental and theoretical efforts in this direction. 展开更多
关键词 composition engineering strategy diatomic catalysts electrocatalytic nitrogen reduction reaction first-principles calculations graphdiyne hierarchical high-throughput screening synergistic effects
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Strategies to achieve effective nitrogen activation
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作者 Bin Chang Huabin Zhang +1 位作者 Shuhui Sun Gaixia Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期137-163,共27页
Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few... Ammonia serves as a crucial chemical raw material and hydrogen energy carrier.Aqueous electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few years.Although some achievements have been revealed in aqueous NRR,significant challenges have also been identified.The activity and selectivity are fundamentally limited by nitrogen activation and competitive hydrogen evolution.This review focuses on the hurdles of nitrogen activation and delves into complementary strategies,including materials design and system optimization(reactor,electrolyte,and mediator).Then,it introduces advanced interdisciplinary technologies that have recently emerged for nitrogen activation using high-energy physics such as plasma and triboelectrification.With a better understanding of the corresponding reaction mechanisms in the coming years,these technologies have the potential to be extended in further applications.This review provides further insight into the reaction mechanisms of selectivity and stability of different reaction systems.We then recommend a rigorous and detailed protocol for investigating NRR performance and also highlight several potential research directions in this exciting field,coupling with advanced interdisciplinary applications,in situ/operando characterizations,and theoretical calculations. 展开更多
关键词 activation via mediators catalyst optimization electrochemical nitrogen fixation high-energy activation of nitrogen nitrogen
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Nitrogen rhizodeposition from corn and soybean,and its contribution to the subsequent wheat crops
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作者 Sainan Geng Lantao Li +6 位作者 Yuhong Miao Yinjie Zhang Xiaona Yu Duo Zhang Qirui Yang Xiao Zhang Yilun Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2446-2457,共12页
Nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important role.Ho... Nitrogen(N)is a key factor in the positive response of cereal crops that follow leguminous crops when compared to gramineous crops in rotations,with the nonrecyclable rhizosphere-derived N playing an important role.However,quantitative assessments of differences in the N derived from rhizodeposition(NdfR)between legumes and gramineous crops are lacking,and comparative studies on their contributions to the subsequent cereals are scarce.In this study,we conducted a meta-analysis of NdfR from leguminous and gramineous crops based on 34 observations published worldwide.In addition,pot experiments were conducted to study the differences in the NdfR amounts,distributions and subsequent effects of two major wheat(Triticum aestivum L.)-preceding crops,corn(Zea mays L.)and soybean(Glycine max L.),by the cotton wick-labelling method in the main wheat-producing areas of China.The meta-analysis results showed that the NdfR of legumes was significantly greater by 138.93%compared to gramineous crops.In our pot experiment,the NdfR values from corn and soybean were 502.32 and 944.12 mg/pot,respectively,and soybean was also significantly higher than corn,accounting for 76.91 and 84.15%of the total belowground nitrogen of the plants,respectively.Moreover,in different soil particle sizes,NdfR was mainly enriched in the large macro-aggregates(>2 mm),followed by the small macro-aggregates(2–0.25 mm).The amount and proportion of NdfR in the macro-aggregates(>0.25 mm)of soybean were 3.48 and 1.66 times higher than those of corn,respectively,indicating the high utilization potential of soybean NdfR.Regarding the N accumulation of subsequent wheat,the contribution of soybean NdfR to wheat was approximately 3 times that of corn,accounting for 8.37 and 4.04%of the total N uptake of wheat,respectively.In conclusion,soybean NdfR is superior to corn in terms of the quantity and distribution ratio of soil macro-aggregates.In future field production,legume NdfR should be included in the nitrogen pool that can be absorbed and utilized by subsequent crops,and the role and potential of leguminous plants as nitrogen source providers in crop rotation systems should be fully utilized. 展开更多
关键词 crop rotation nitrogen rhizodeposition meta-analysis soil aggregates nitrogen transfer
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An optimized strategy of nitrogen-split application based on the leaf positional differences in chlorophyll meter readings
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作者 Gaozhao Wu Xingyu Chen +9 位作者 Yuguang Zang Ying Ye Xiaoqing Qian Weiyang Zhang Hao Zhang Lijun Liu Zujian Zhang Zhiqin Wang Junfei Gu Jianchang Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2605-2617,共13页
Modern rice production faces the dual challenges of increasing grain yields while reducing inputs of chemical fertilizer.However,the disequilibrium between the nitrogen(N)supplement from the soil and the demand for N ... Modern rice production faces the dual challenges of increasing grain yields while reducing inputs of chemical fertilizer.However,the disequilibrium between the nitrogen(N)supplement from the soil and the demand for N of plants is a serious obstacle to achieving these goals.Plant-based diagnosis can help farmers make better choices regarding the timing and amount of topdressing N fertilizer.Our objective was to evaluate a non-destructive assessment of rice N demands based on the relative SPAD value(RSPAD)due to leaf positional differences.In this study,two field experiments were conducted,including a field experiment of different N rates(Exp.I)and an experiment to evaluate the new strategy of nitrogen-split application based on RSPAD(Exp.II).The results showed that higher N inputs significantly increased grain yield in modern high yielding super rice,but at the expense of lower nitrogen use efficiency(NUE).The N nutrition index(NNI)can adequately differentiate situations of excessive,optimal,and insufficient N nutrition in rice,and the optimal N rate for modern high yielding rice is higher than conventional cultivars.The RSPAD is calculated as the SPAD value of the top fully expanded leaf vs.the value of the third leaf,which takes into account the non-uniform N distribution within a canopy.The RSPAD can be used as an indicator for higher yield and NUE,and guide better management of N fertilizer application.Furthermore,we developed a new strategy of nitrogen-split application based on RSPAD,in which the N rate was reduced by 18.7%,yield was increased by 1.7%,and the agronomic N use efficiency was increased by 27.8%,when compared with standard farmers'practices.This strategy of N fertilization shows great potential for ensuring high yielding and improving NUE at lower N inputs. 展开更多
关键词 CANOPY crop management practices nitrogen nitrogen nutrition index rice SPAD
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Isotope constraints on seasonal dynamics of nitrogen in Zhanjiang Bay, a typical mariculture bay in South China
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作者 Chunqing Chen Qibin Lao +3 位作者 Fajin Chen Guangzhe Jin Jiacheng Li Qingmei Zhu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期60-70,共11页
Eutrophication in coastal waters has been increasing remarkably,severely impacting the water quality in mariculture bays.In this study,we conducted multiple isotopic measurements on suspended particulate nitrogen(δ^(... Eutrophication in coastal waters has been increasing remarkably,severely impacting the water quality in mariculture bays.In this study,we conducted multiple isotopic measurements on suspended particulate nitrogen(δ^(15)N-PN) and dissolved nitrate(δ^(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)) in Zhanjiang Bay,a typical mariculture bay with a high level of eutrophication in South China,to investigate the changes in nitrogen sources and their cycling between the rainy and dry seasons.During the rainy season,the study found no significant relation between δ^(15)NPN and δ^(15)N-NO_(3)^(-)due to the impact of heavy rainfall and terrestrial erosion.In the upper bay,a slight nitrate loss and slightly higher δ_(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)values were observed,attributed to intense physical sedimentwater interactions.Despite some fluctuations,nitrate concentrations in the lower bay mainly aligned with the theoretical mixing line during the rainy season,suggesting that nitrate was primarily influenced by terrestrial erosion and that nitrate isotopes resembled the source.Consequently,the isotopic values of nitrate can be used for source apportionment in the rainy season.The results indicated that soil nitrogen(36%) and manure and sewage(33%) were the predominant nitrogen sources contributing to nitrogen loads during this period.In contrast,the dry season saw a deficient ammonium concentration(<0.2 μmol/L) in the bay,due to nearly complete consumption by phytoplankton during the red tide period.Additionally,the significant loss of nitrate and simultaneous increase in the stable isotopes of dissolved and particulate nitrogen suggest a strong coupling of assimilation and mineralization during the dry season.More active biogeochemical processes during the dry season may be related to decreased runoff and increased water retention time.Overall,our study illustrated the major seasonal nitrogen sources and their dynamics in Zhanjiang B ay,providing valuable insights for formulating effective policies to mitigate eutrophication in mariculture bays. 展开更多
关键词 nitrogen stable nitrogen isotopes biogeochemical processes EUTROPHICATION Zhanjiang Bay
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Influence of nitrogen status on fermentation performances of non-Saccharomyces yeasts:a review
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作者 Jinchen Li Mengmeng Yuan +3 位作者 Nan Meng Hehe Li Jinyuan Sun Baoguo Sun 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期556-567,共12页
Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances inclu... Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic fermentation.Such influences are imposed on yeast growth and fermentation performances including the formation of secondary metabolites.Saccharomyces cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen impacts.On the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being reported.This review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent studies.Detailed discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final section.In summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile production.Research gaps will therefore be elucidated for future research. 展开更多
关键词 Non-Saccharomyces yeasts nitrogen Fermentation kinetics nitrogen preference Wine aroma
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Tracing nitrate sources in one of the world's largest eutrophicated bays(Hangzhou Bay):insights from nitrogen and oxygen isotopes
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作者 Zhi Yang Jianfang Chen +6 位作者 Haiyan Jin Hongliang Li Zhongqiang Ji Yangjie Li Bin Wang Zhenyi Cao Qianna Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期86-95,共10页
Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributi... Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributions of salinity,nutrients [nitrate(NO_(3)^(-)),nitrite,ammonium,and phosphate],and the stable isotopic composition of NO_(3)^(-)(δ^(15)N and δ^(18)O) were used to investigate sources of dissolved inorganic nitrogen(DIN) to Hangzhou B ay.Spatial distributions of nitrate,salinity,and nitrate δ^(18)O indicate that the Qiantang River,the Changjiang River,and nearshore coastal waters may all contribute nitrate to the bay.Based on the isotopic compositions of nitrate in these potential source waters and conservative mixing of nitrate in our study area,we suggest that the NO_(3)^(- )in Hangzhou B ay was likely derived mainly from soils,synthetic N fertilizer,and manure and sewage.End-member modeling indicates that in the upper half of the bay,the Qiantang River was a very important DIN source,possibly contributing more than 50% of DIN in the bay head area.In the lower half of the bay,DIN was sourced mainly from strongly intruding coastal water.DIN coming directly from the Changjiang River made a relatively small contribution to Hangzhou Bay DIN in August 2019. 展开更多
关键词 nitrogen isotopes oxygen isotopes nitrogen cycle nitrate sources Hangzhou Bay
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Plant Nitrogen Metabolism: Balancing Resilience to Nutritional Stress andAbiotic Challenges
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作者 Muhammad Farhan Manda Sathish +10 位作者 Rafia Kiran Aroosa Mushtaq Alaa Baazeem Ammarah Hasnain Fahad Hakim Syed Atif Hasan Naqvi Mustansar Mubeen Yasir Iftikhar Aqleem Abbas Muhammad Zeeshan Hassan Mahmoud Moustafa 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期581-609,共29页
Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen metabolism.This review explores nitrogen’s regulatory role in plant responses to these challenges,unvei... Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen metabolism.This review explores nitrogen’s regulatory role in plant responses to these challenges,unveiling a dynamic interplay between nitrogen availability and abiotic stress.In the context of soil salinity,a nuanced rela-tionship emerges,featuring both antagonistic and synergistic interactions between salinity and nitrogen levels.Salinity-induced chlorophyll depletion in plants can be alleviated by optimal nitrogen supplementation;however,excessive nitrogen can exacerbate salinity stress.We delve into the complexities of this interaction and its agri-cultural implications.Nitrogen,a vital element within essential plant structures like chloroplasts,elicits diverse responses based on its availability.This review comprehensively examines manifestations of nitrogen deficiency and toxicity across various crop types,including cereals,vegetables,legumes,and fruits.Furthermore,we explore the broader consequences of nitrogen products,such as N_(2)O,NO_(2),and ammonia,on human health.Understand-ing the intricate relationship between nitrogen and salinity,especially chloride accumulation in nitrate-fed plants and sodium buildup in ammonium-fed plants,is pivotal for optimizing crop nitrogen management.However,prudent nitrogen use is essential,as overapplication can exacerbate nitrogen-related issues.Nitrogen Use Effi-ciency(NUE)is of paramount importance in addressing salinity challenges and enhancing sustainable crop productivity.Achieving this goal requires advancements in crop varieties with efficient nitrogen utilization,pre-cise timing and placement of nitrogen fertilizer application,and thoughtful nitrogen source selection to mitigate losses,particularly urea-based fertilizer volatilization.This review article delves into the multifaceted world of plant nitrogen metabolism and its pivotal role in enabling plant resilience to nutritional stress and abiotic challenges.It offers insights into future directions for sustainable agriculture. 展开更多
关键词 Synthetic nitrogen nitrogen signaling sustainable agriculture EUTROPHICATION AMMONIUM NITRATE
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Water and nitrogen footprint assessment of integrated agronomic practice management in a summer maize cropping system
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作者 Ningning Yu Bingshuo Wang +3 位作者 Baizhao Ren Bin Zhao Peng Liu Jiwang Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3610-3621,共12页
The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two ... The footprints of water and nitrogen(WF and NF)provide a comprehensive overview of the type and quantity of water consumption and reactive nitrogen(Nr)loss in crop production.In this study,a field experiment over two years(2019 and 2020)compared three integrated agronomic practice management(IAPM)systems:An improved management system(T2),a high-yield production system(T3),and an integrated soil-crop management system(ISCM)using a local smallholder farmer’s practice system(T1)as control,to investigate the responses of WF,Nr losses,water use efficiency(WUE),and nitrogen use efficiency(NUE)to IAPM.The results showed that IAPM optimized water distribution and promoted water use by summer maize.The evapotranspiration over the whole maize growth period of IAPM increased,but yield increased more,leading to a significant increase in WUE.The WUE of the T2,T3,and ISCM treatments was significantly greater than in the T1 treatment,in 2019 and 2020respectively,by 19.8-21.5,31.8-40.6,and 34.4-44.6%.The lowest WF was found in the ISCM treatment,which was 31.0%lower than that of the T1 treatment.In addition,the ISCM treatment optimized soil total nitrogen(TN)distribution and significantly increased TN in the cultivated layer.Excessive nitrogen fertilizer was applied in treatment T3,producing the highest maize yield,and resulting in the highest Nr losses.In contrast,the ISCM treatment used a reduced nitrogen fertilizer rate,sacrificing grain yield partly,which reduced Nr losses and eventually led to a significant increase in nitrogen use efficiency and nitrogen recovery.The Nr level in the ISCM treatment was34.8%lower than in the T1 treatment while NUE was significantly higher than in the T1 treatment by 56.8-63.1%in2019 and 2020,respectively.Considering yield,WUE,NUE,WF,and NF together,ISCM should be used as a more sustainable and clean system for sustainable production of summer maize. 展开更多
关键词 integrated agronomic practice management water footprints nitrogen footprints water use efficiency nitrogen use efficiency yield
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Genetic and Agronomic Parameter Estimates of Growth, Yield and Related Traits of Maize (Zea mays L.) under Different Rates of Nitrogen Fertilization
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作者 Prince Emmanuel Norman Lansana Kamara +6 位作者 Aloysius Beah Kelvin Sahr Gborie Francess Sia Saquee Sheku Alfred Kanu Fayia Augustine Kassoh Yvonne Sylvia Gloria Ethel Norman Abdul Salaam Kargbo 《American Journal of Plant Sciences》 CAS 2024年第4期274-291,共18页
This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in... This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup>) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p < 0.05) influenced grain yield production. Mean grain yields and economic parameter estimates increased with increasing nitrogen rates, with the 30 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup> plots exhibiting the lowest and highest grain yields of 1238 kg∙ha<sup>−</sup><sup>1</sup> and 2098 kg∙ha<sup>−</sup><sup>1</sup>, respectively. Variety and nitrogen effects on partial factor productivity (PFP<sub>N</sub>), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p < 0.05) by these factors. The highest PFP<sub>N</sub> (41.3 kg grain kg<sup>−</sup><sup>1</sup>∙N) and AEN (29.4 kg grain kg<sup>−</sup><sup>1</sup>∙N) were obtained in the 30 kg∙N∙ha<sup>−</sup><sup>1</sup> plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL<sup>−</sup><sup>1</sup> spent on N) were obtained in the 180 kg∙N∙ha<sup>−</sup><sup>1</sup>. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fertilization and improved farming practices that could be exploited for increased productivity of maize. 展开更多
关键词 nitrogen Rates Genetic and Agronomic Estimates Introduced Genotypes Grain Yield Zea mays
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Development of a novel critical nitrogen concentration-cumulative transpiration curve for optimizing nitrogen management under varying irrigation conditions in winter wheat
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作者 Tianyang Ye Yu Zhang +9 位作者 Jingyan Xuan Xintian Wang Yang Li Junhao Xu Liujun Xiao Leilei Liu Liang Tang Weixing Cao Bing Liu Yan Zhu 《The Crop Journal》 SCIE CSCD 2024年第4期1242-1251,共10页
Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop w... Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop water status.With three-year field experiments with winter wheat,encompassing two irrigation levels(rainfed and irrigation at jointing and anthesis)and three N levels(0,180,and 270 kg ha1),this study aims to establish a novel approach for determining the Nc dilution curve based on crop cumulative transpiration(T),providing a comprehensive analysis of the interaction between N and water availability.The Nc curves derived from both crop dry matter(DM)and T demonstrated N concentration dilution under different conditions with different parameters.The equation Nc=6.43T0.24 established a consistent relationship across varying irrigation regimes.Independent test results indicated that the nitrogen nutrition index(NNI),calculated from this curve,effectively identifies and quantifies the two sources of N deficiency:insufficient N supply in the soil and insufficient soil water concentration leading to decreased N availability for root absorption.Additionally,the NNI calculated from the Nc-DM and Nc-T curves exhibited a strong negative correlation with accumulated N deficit(Nand)and a positive correlation with relative grain yield(RGY).The NNI derived from the Nc-T curve outperformed the NNI derived from the Nc-DM curve concerning its relationship with Nand and RGY,as indicated by larger R2 values and smaller AIC.The novel Nc curve based on T serves as an effective diagnostic tool for assessing winter wheat N status,predicting grain yield,and optimizing N fertilizer management across varying irrigation conditions.These findings would provide new insights and methods to improve the simulations of water-N interaction relationship in crop growth models. 展开更多
关键词 Crop dry matter Crop cumulative transpiration Bayesian statistical model Critical nitrogen dilution curve nitrogen nutrition index
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One-Step Scalable Fabrication of Nitrogen and Chlorine Co-doped Graphene by Electrochemical Exfoliation for High-Performance Supercapacitors
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作者 Qian Li Hu Zheng +4 位作者 Binbin Liu Tianzhen Jian Wenqing Ma Caixia Xu Kai Wang 《Transactions of Tianjin University》 EI CAS 2024年第5期448-458,共11页
The stacking and aggregation of graphene nanosheets have been obstacles to their application as electrode materials for microelectronic devices.This study deploys a one-step,scalable,facile electrochemical exfoliation... The stacking and aggregation of graphene nanosheets have been obstacles to their application as electrode materials for microelectronic devices.This study deploys a one-step,scalable,facile electrochemical exfoliation technique to fabricate nitrogen(N)and chlorine(Cl)co-doped graphene nanosheets(i.e.,N-Cl-G)via the application of constant voltage on graphite in a mixture of 0.1 mol/L H_(2)SO_(4)and 0.1 mol/L NH_(4)Cl without using dangerous and exhaustive operation.The introduction of Cl(with its large radius)and N,both with high electrical negativity,facilitates the modulation of the electronic structure of graphene and creation of rich structural defects in it.Consequently,in the as-constructed supercapacitors,N-Cl-G exhibits a high specific capacitance of 77 F/g at 0.2 A/g and remarkable cycling stability with 91.7%retention of initial capacitance after 20,000 cycles at 10 A/g.Furthermore,a symmetrical supercapacitor assembled with N-Cl-G as the positive and negative electrodes(denoted as N-Cl-G//N-Cl-G)exhibits an energy density of 3.38 Wh/kg at a power density of 600 W/kg and superior cycling stability with almost no capacitance loss after 5000 cycles at 5 A/g.This study provides a scalable protocol for the facile fabrication of high-performance co-doped graphene as an electrode material candidate for supercapacitors. 展开更多
关键词 GRAPHENE Electrochemical exfoliation Supercapacitor nitrogen CHLORINE
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The nitrogen transformation behavior based on the pyrolysis products of wheat straw
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作者 Shun Guo Yunfei Li +1 位作者 Shengwei Tang Tao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期58-65,共8页
In order to provide basic design parameters for the industrial pyrolysis process,the transformation behavior of nitrogen was investigated using wheat straw as raw material.The distributions of nitrogen in pyrolysis ch... In order to provide basic design parameters for the industrial pyrolysis process,the transformation behavior of nitrogen was investigated using wheat straw as raw material.The distributions of nitrogen in pyrolysis char,oil,and gas were obtained and the nitrogenous components in the products were analyzed systematically by X-ray photoelectron spectroscopy(XPS),pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)and thermogravimetric-Fourier transform infrared spectrometry(TG-FTIR).The nitrogen distribution ranges of the pyrolysis char,oil,and gas were 37.34%–54.82%,32.87%–40.94%and 10.20%–28.83%,respectively.More nitrogen was retained in char at lower pyrolysis temperature and the nitrogen distribution of oil was from rise to decline with increasing temperature.The most abundant N-containing compounds in three-phase products were pyrrole-N,amines,and HCN,respectively.In addition,the transformation mechanism of nitrogen from wheat straw to pyrolysis products was concluded. 展开更多
关键词 PYROLYSIS nitrogen transformation Wheat straw Py-GC/MS TG-FTIR
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Environmental concentration of ammonia nitrogen induced marked changes in proteome of clam Ruditapes philippinarum in dose-and time-dependent manner
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作者 Ming CONG Zhaoshun LI +2 位作者 Wenwen TIAN Yuanmei LI Jiasen LÜ 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1634-1650,共17页
Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,whic... Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,which is vital to elucidate the underlying mechanism of ammonia nitrogen.In this study,clams R.philippinarum were exposed to ammonia nitrogen for 21 d at two environmentally relevant concentrations.The tandem mass tags approach(TMT)was applied to assay the differentially expressed proteins(DEPs)in clam gill tissues on the 3 rd and 21 st day.Finally,a total of 7263 proteins were identified.Bioinformatics analyses revealed that clam protein profiles changed in dose-and time dependent manner after ammonia nitrogen exposure.We inferred that the clams may face heavy challenges after ammonia exposure,such as unbalanced gender ratio,lysosomal disease,energy lack,neurological disorders,altered glutamine metabolism,increased lipid synthesis,and impaired immunity.Variation profiles of enzyme activities of glutaminase and glutamine synthase provided direct evidence to verify the related inference from proteome data.Most of the inferred toxic effects merit further study.This study identified important proteins related to ammonia nitrogen toxicity in the clam and indicated the severe stress of marine ammonia pollution on the healthy development of mollusc aquaculture. 展开更多
关键词 ammonia nitrogen Ruditapes philippinarum proteomic analysis TOXICITY
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Appropriate Supply of Ammonium Nitrogen and Ammonium Nitrate Reduces Cadmium Content in Rice Seedlings by Inhibiting Cadmium Uptake and Transport
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作者 HU Yunchao YAN Tiancai +13 位作者 GAO Zhenyu WANG Tiankang LU Xueli YANG Long SHEN Lan ZHANG Qiang HU Jiang REN Deyong ZHANG Guangheng ZHU Li LI Li ZENG Dali QIAN Qian LI Qing 《Rice science》 SCIE CSCD 2024年第5期587-602,I0062-I0064,共19页
Reasonable nitrogen(N) application is a promising strategy for reducing crop cadmium(Cd) toxicity. However, the specific form of N and the required amount that affect Cd tolerance and accumulation in rice remain uncle... Reasonable nitrogen(N) application is a promising strategy for reducing crop cadmium(Cd) toxicity. However, the specific form of N and the required amount that affect Cd tolerance and accumulation in rice remain unclear. This study explored the influence of different N-fertilizer forms(NH_(4)NO_(3), NH_4Cl, and KNO_(3)) and dosages on Cd tolerance and uptake in Cd-stressed N-sensitive and N-insensitive indica rice accessions. The results indicated that the Cd tolerance of N-sensitive indica accessions is more robust than that of N-insensitive ones. Furthermore, the shoot Cd content and Cd translocation rate in both N-sensitive and N-insensitive indica accessions decreased with an appropriate supply of NH_(4)NO_(3) and NH_4Cl, whereas they were comparable or slightly increased with increased KNO_(3). Unfortunately, we did not find significant and regular differences in Cd accumulation or translocation between N-sensitive and N-insensitive rice accessions. Consistent with the reduction of shoot Cd content, the addition of NH_(4)NO_(3) and NH_4Cl also inhibited the instantaneous root Cd^(2+) uptake. The expression changes of Cd transport-related genes under different N forms and dosages suggested that the decreased shoot Cd content, caused by the increased supply of NH_(4)NO_(3) and NH_4Cl, is likely achieved by reducing the transcription of OsNRAMP1 and OsIRT1. In summary, our findings reveal that an appropriate supply of NH_(4)NO_(3) and NH_4Cl could reduce Cd uptake and transport in rice seedlings, suggesting that rational N management could reduce the Cd risk in rice production. 展开更多
关键词 Oryza sativa CADMIUM nitrogen ammonium nitrate ammonium chloride
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