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Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of China
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作者 Wenjie Yang Jie Yu +9 位作者 Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing Cao Jinshan Liu Weihong Qiu Zhaohui Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2421-2433,共13页
The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status... The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical fertilizers.Critical nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential yield.Based on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of China,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern China.The results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at harvest.However,yield was not correlated with the inputs of N,P,and K fertilizers.Based on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,respectively.Then,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,and<95%)and the model,the five groups of topsoil critical nutrient levels and fertilization coefficients(Fc)were determined.Finally,we proposed a new method for calculating the recommended fertilizer input rate as:Fr=Gy×Nr×Fc,where Fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and Fc is a coefficient for N(N_c)/P(P_c)/K(K_c)fertilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer input by 43.5%(57.5 kg P_(2)O_(5) ha^(-1))in northern China and did not reduce the wheat yield.This outcome can significantly increase the farmers’benefits(by 7.58%,or 139 US$ha^(-1)).Therefore,this new recommended fertilization method can be used as a tool to guide N,P,and K fertilizer application rates for dryland wheat production. 展开更多
关键词 fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients
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Litter Productivity and Nutrient Return Characteristics of Three Typical Forest Stands in Golden Mountain
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作者 Fengchen Yan Jiang Zhu +2 位作者 Juyang Wu Jinshi Chen Zijun Tian 《Open Journal of Applied Sciences》 2024年第2期353-370,共18页
Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study i... Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study in southwest Hubei Province and carbon sink function of the whole forest ecosystem. Methods: Three typical forest stands (Chinese fir plantation, Cryptomeria fortunei plantation and evergreen and deciduous broad-leaved mixed forest) in Golden Mountain Forest Farm in southwest Hubei Province were investigated and monitored continuously for the litter types and productivity and nutrient return. Results: The annual litter productivity of the three forest stands ranged from 161.77 to 396.26 kg·hm<sup>-2</sup>;Litters of branches, leaves and reproductive organs accounted for 14.14% - 20.85%, 33.26% - 78.33%, 7.52% - 42.18% of the total, respectively;The litter productivity and total litter productivity of each composition in the three forest stands show unimodal or bimodal changes over months, and the total litter productivity reached the highest value in January, April and October respectively. For different nutrient contents of the three forest stands, the common feature is C > N. The order of nutrient return amount from greatest to least is evergreen and deciduous broad-leaved mixed forest, Cryptomeria fortunei plantation and Chinese fir plantation. For different nutrient return amounts, the common feature is C > N, and the nutrient return amounts are 76.51-180.69 kg·hm<sup>-2</sup> and 2.3 - 5.71 kg·hm<sup>-2</sup> respectively. Conclusion: The annual litter productivity and nutrient return amount of the evergreen and deciduous broad-leaved mixed forest are the highest among the three forest stands. Therefore, protecting the evergreen and deciduous broad-leaved mixed forest and studying the litter changes of Chinese fir plantation and Cryptomeria fortunei plantation are of far-reaching significance for the development of sustainable forest management in this region and the further improvement of the carbon sequestration function of the whole forest ecosystem. 展开更多
关键词 Golden Mountain Litter Productivity nutrient Return Amount nutrient Content
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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize 被引量:1
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens 被引量:1
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作者 Yuan Yuan Shun Zhong +3 位作者 Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1567-1577,共11页
The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were i... The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods. 展开更多
关键词 Bee pollen nutrientS Wall disruption Phenolic compounds In vitro digestion
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Litterfall production modeling based on climatic variables and nutrient return from stands of Eucalyptus grandis Hill ex Maiden and Pinus taeda L.
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作者 Andrés Baietto Andrés Hirigoyen +1 位作者 Jorge Hernández Amabelia del Pino 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期26-36,共11页
Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus stands.The short rotation regimes used for the stands require high nutrient levels,with litterfall being a major... Native grasslands in the Pampas of South America are increasingly being replaced by Eucalyptus and Pinus stands.The short rotation regimes used for the stands require high nutrient levels,with litterfall being a major source of nutrient return.To model the litterfall production using climatic variables and assess the nutrient return in 14-year-old Eucalyptus grandis and Pinus taeda stands,we measured litter production over 2 years,using conical litter traps,and monitored climatic variables.Mean temperature,accumulated precipitation,and mean maximum vapor pres-sure deficit at the seasonal level influenced litterfall produc-tion by E.grandis;seasonal accumulated precipitation and mean maximum temperature affected litterfall by P.taeda.The regression tree modeling based on these climatic vari-ables had great accuracy and predictive power for E.grandis(N=33;MAE(mean absolute error)=0.65;RMSE(root mean square error)=0.91;R^(2)=0.71)and P.taeda(N=108;MAE=1.50;RMSE=1.59;R^(2)=0.72).The nutrient return followed a similar pattern to litterfall deposition,as well as the order of importance of macronutrients(E.grandis:Ca>N>K>Mg>P;P.taeda:N>Ca>K>Mg>P)and micronutrients(E.grandis and P.taeda:Mn>Fe>Zn>Cu)in both species.This study constitutes a first approximation of factors that affect litterfall and nutrient return in these systems. 展开更多
关键词 AFFORESTATION LITTERFALL nutrient recycling Climate modeling MYRTACEAE PINACEAE
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Characterization of Nutrients,Heavy Metals,Petroleum and Their Impact on Phytoplankton in Laizhou Bay:Implications for Environmental Management and Monitoring
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作者 WANG Kai ZHAO Linlin +3 位作者 ZHU Yugui YANG Liqiang WANG Yunfeng HONG Xuguang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期822-834,共13页
The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petro... The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental challenges.This study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in LB.The results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the SWLB.After adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)concentrations.We highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community structure.Therefore,it is recommended that more monitoring and management efforts be focused on these regions in the future. 展开更多
关键词 Huanghe River Estuary Laizhou Bay nutrientS heavy metals PHYTOPLANKTON BIODIVERSITY
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Litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon
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作者 Ricardo Antonio Marenco Saul Alfredo Antezana-Vera +1 位作者 Daniela Pereira Dias Luiz Antonio Candido 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期131-141,共11页
Litterfall is the largest source of nutrients to for-est soils of tropical rainforests.However,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seas... Litterfall is the largest source of nutrients to for-est soils of tropical rainforests.However,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central Amazon.This study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central Amazon.Litterfall was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates determined.Leaf area index was also recorded in the dry and rainy seasons.Monthly litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy season.Climatic seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality oppositely.While phosphorous increased,potassium decreased during the dry season.Over seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf aging.Regardless,the five nutrients had similar remobilization rates over the year.The absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change. 展开更多
关键词 THROUGHFALL nutrient cycling Climatic seasonality Leaf mass per area
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Effects of inorganic nutrients and environmental factors on the removal of n-propylbenzene and isopropylbenzene in seawater by cryptophytes Rhinomonas reticulata S6A
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作者 Jiali CUI Shuhao DU +3 位作者 Yumei LI Haiping LI Ping ZHANG Fanping MENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1200-1215,共16页
To effectively remove n-propylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)leaked into seawater using Rhinomonas reticulata S6A(a newly isolated marine microalga),the effects of three inorganic nutrients and four environm... To effectively remove n-propylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)leaked into seawater using Rhinomonas reticulata S6A(a newly isolated marine microalga),the effects of three inorganic nutrients and four environmental factors on their degradation were determined after 7 d of inoculation.Results show that NaNO_(3) at 300 mg/L caused a higher removal efficiency of both n-PBZ and i-PBZ(44.79%and 39.26%),while for NaH_(2) PO_(4)·H_(2) O,greater removal rates of two PBZs(47.30%and 42.23%)were achieved at 30 and 20 mg/L,respectively.NaHCO_(3) supplementation(500-750 mg/L)resulted in a large reduction(43.67%-45.04%)in i-PBZ concentration.The change in seawater pH(from 6 to 9)did not affect the elimination of n-PBZ and i-PBZ.The most suitable salinity and temperature were 30 and 25-30℃,respectively,leading to the PBZs removal of~40%.Light intensity exhibited significant influence on elimination of PBZs,and the maximum removal efficiencies of 56.07%(n-PBZ)and 55.00%(i-PBZ)were recorded under 200 and 600μmol/(m^(2)·s),respectively.In addition,the microalga could still remove PBZs when it failed to grow well due to darkness,strong light,low temperature,or low salinity,which might mean that good growth of alga is not always a necessary condition for PBZs removal.Therefore,attention should be paid to the suitability of nutrient levels and environmental conditions(excluding pH)in seawater when using microalgae for bioremediating PBZs-contaminated seawater. 展开更多
关键词 propylbenzene(PBZ) Rhinomonas reticulata seawater inorganic nutrient environmental factor
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Effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets
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作者 Zexi Li Yunfei Li +6 位作者 Yufei Zhao Guifu Wang Rujie Liu Yue Li Qamar Aftab Zewei Sun Qingzhen Zhong 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2106-2121,共16页
Background Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization.The rational allocation of dietary starch sources and th... Background Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization.The rational allocation of dietary starch sources and the exploration of appropriate dietary glucose release kinetics may promote the dynamic balance of dietary glucose and amino acid supplies.However,research on the effects of diets with different glucose release kinetic profiles on amino acid absorption and portal amino acid appearance in piglets is limited.This study aimed to investigate the effects of the kinetic pattern of dietary glucose release on nitrogen utilization,the portal amino acid profile,and nutrient transporter expression in intestinal enterocytes in piglets.Methods Sixty-four barrows(15.00±1.12 kg)were randomly allotted to 4 groups and fed diets formulated with starch from corn,corn/barley,corn/sorghum,or corn/cassava combinations(diets were coded A,B,C,or D respectively).Protein retention,the concentrations of portal amino acid and glucose,and the relative expression of amino acid and glucose transporter m RNAs were investigated.In vitro digestion was used to compare the dietary glucose release profiles.Results Four piglet diets with different glucose release kinetics were constructed by adjusting starch sources.The in vivo appearance dynamics of portal glucose were consistent with those of in vitro dietary glucose release kinetics.Total nitrogen excretion was reduced in the piglets in group B,while apparent nitrogen digestibility and nitrogen retention increased(P<0.05).Regardless of the time(2 h or 4 h after morning feeding),the portal total free amino acids content and contents of some individual amino acids(Thr,Glu,Gly,Ala,and Ile)of the piglets in group B were significantly higher than those in groups A,C,and D(P<0.05).Cluster analysis showed that different glucose release kinetic patterns resulted in different portal amino acid patterns in piglets,which decreased gradually with the extension of feeding time.The portal His/Phe,Pro/Glu,Leu/Val,Lys/Met,Tyr/Ile and Ala/Gly appeared higher similarity among the diet treatments.In the anterior jejunum,the glucose transporter SGLT1 was significantly positively correlated with the amino acid transporters B0AT1,EAAC1,and CAT1.Conclusions Rational allocation of starch resources could regulate dietary glucose release kinetics.In the present study,group B(corn/barley)diet exhibited a better glucose release kinetic pattern than the other groups,which could affect the portal amino acid contents and patterns by regulating the expression of amino acid transporters in the small intestine,thereby promoting nitrogen deposition in the body,and improving the utilization efficiency of dietary nitrogen. 展开更多
关键词 Glucose release kinetics Nitrogen utilization nutrient transporter PIGLET
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Linking nutrient resorption stoichiometry with plant growth under long-term nitrogen addition
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作者 Aijun Xing Haihua Shen +3 位作者 Longchao Xu Mengying Zhao Zhengbing Yan Jingyun Fang 《Forest Ecosystems》 SCIE CSCD 2024年第5期642-649,共8页
Increased nitrogen(N)input can potentially lead to secondary phosphorus(P)limitation;however,it remains unclear whether differences in the plant's ability to cope with this P deficiency are related to their growth... Increased nitrogen(N)input can potentially lead to secondary phosphorus(P)limitation;however,it remains unclear whether differences in the plant's ability to cope with this P deficiency are related to their growth responses.Using a long-term experiment of N addition in a boreal forest,we explored the potential role of plant nutrient resorption efficiency and its stoichiometry in mediating plant growth responses to increased N input.We recorded the cover and measured the concentration and resorption efficiency of leaf N and P as well as the photosynthesis of a grass Deyeuxia angustifolia and a shrub Vaccinium vitis-idaea.The cover of the grass D.angustifolia increased with increasing N addition,while that of the shrub V.vitis-idaea decreased with N addition rate and almost disappeared from the high-level N addition over time.P resorption efficiency(PRE)increased in D.angustifolia but decreased in V.vitis-idaea with increasing leaf N:P which was increased by N addition for both species.In addition,photosynthesis increased linearly with N resorption efficiency(NRE)and PRE but was better explained by NRE:PRE,changing nonlinearly with the ratio in a hump-shaped trend.Furthermore,the variance(CV)of NRE:PRE for V.vitis-idaea(123%)was considerably higher than that for D.angustifolia(29%),indicating a more stable nutrient resorption stoichiometry of the grass.Taken together,these results highlight that efficient P acquisition and use strategy through nutrient resorption processes could be a pivotal underlying mechanism driving plant growth and community composition shifts under N enrichment. 展开更多
关键词 Nitrogen deposition Understory layer Community shift nutrient limitation Phosphorus resorption efficiency Stoichiometric homeostasis
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Effects of nutrient limitations on the sinking velocity of Thalassiosira weissflogii
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作者 Jie Zhu Qiang Hao +2 位作者 Wei Zhang Yingying Ma Jiangning Zeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期163-172,共10页
The sinking of diatoms is critic al to the formation of oceanic biological pumps and coastal hypoxic zones.However,little is known about the effects of different nutrient restrictions on diatom sinking.In this study,w... The sinking of diatoms is critic al to the formation of oceanic biological pumps and coastal hypoxic zones.However,little is known about the effects of different nutrient restrictions on diatom sinking.In this study,we measured the sinking velocity(SV) of Thalassiosira weissflogii using a new phytoplankton video observation instrument and analyzed major biochemical components under varying nutrient conditions.Our results showed that the SV of T.weissflogii under different nutrient limitation conditions varied substantially.The highest SV of(1.77±0.02) m/d was obtained under nitrate limitation,signific antly surpassing that under phosphate limitation at(0.98±0.13) m/d.As the nutrient limitation was released,the SV steadily decreased to(0.32±0.03) m/d and(0.15±0.05) m/d,respectively.Notably;under conditions with limited nitrate and phosphate concentrations,the SV values of T.weissflogii significantly positively correlated with the lipid content(P <0.001),with R^(2) values of 0.86 and 0.69,respectively.The change of the phytoplankton SV was primarily related to the intracellular compo sition,which is controlled by nutrient conditions but did not significantly correlate with transparent extracellular polymer and biosilica contents.The results of this study help to understand the regulation of the vertical sinking process of diatoms by nutrient restriction and provide new insights into phytoplankton dynamics and their relationship with the marine nutrient structure. 展开更多
关键词 nutrient limitation Thalassiosira weissflogii sinking velocity biochemical component lipid content
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Large-scale interplant exchange of macromolecules between soybean and dodder under nutrient stresses
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作者 Jingxiong Zhang Shalan Li +9 位作者 Wenxing Li Zerui Feng Shuhan Zhang Xijie Zheng Yuxing Xu Guojing Shen Man Zhao Guoyan Cao Xuna Wu Jianqiang Wu 《Plant Diversity》 SCIE CAS CSCD 2024年第1期116-125,共10页
Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adap... Parasitic plants and their hosts communicate through haustorial connections.Nutrient deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient stresses.In this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N or-P.Importantly,large-scale interplant transport of mRNAs and proteins was detected.Although the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant communications.Furthermore,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently regulated.This study provides new insight into the communication between host plants and parasites under stress conditions. 展开更多
关键词 CUSCUTA Mobile molecules nutrient deficiency Host plant-parasitic plant interaction Interplant transport Systemic signaling
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Response of soil nutrients to terracing and environmental factors in the Loess Plateau of China
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作者 Die Chen Wei Wei +2 位作者 Liding Chen Bojun Ma Hao Li 《Geography and Sustainability》 CSCD 2024年第2期230-240,共11页
Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in... Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water resources.Soil nutrients play a crucial role in determining soil quality,particularly in landscapes prone to drought.They are influenced by factors such as land-use type,slope aspect,and altitude.In this study,we sought to examine the impact of terracing on soil nutrients(soil organic content(SOC),total nitrogen(TN),nitrate-nitrogen(NO_(3)^(-)-N),ammonium nitrogen(NH_(4)^(+)-N),total phosphorus(TP),available phosphorus(AP),total potassium(TK),and available potassium(AK))and how they vary with environmental factors in the Chinese Loess Plateau.During the growing season,we collected 540 soil samples from the 0 to 100 cm soil layer across five major land-use types,different slope aspects,and varying altitudes.Additionally,a meta-analysis of literature data further corroborated the effective accumulation of soil nutrients through terracing in the Loess Plateau.Our findings are as follows:(1)Terraced fields,regardless of land-use type,showed a significant improvement in SOC and TN content.(2)Soil nutrient contents within terraced fields were predominantly higher on sunny slopes.(3)Terraces at lower altitudes are characterized by elevated SOC concentrations.(4)A meta-analysis of literature data pertaining to terracing and soil nutrients in this region confirmed the effective accumulation of soil nutri-ents through terracing.The elucidated outcomes of this study offer a profound theoretical underpinning for the accurate planning and management of terraces,the scientific utilization of land resources,and the enhancement of land productivity. 展开更多
关键词 TERRACE Soil nutrients Land-use Slope aspect ALTITUDE Loess Plateau
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A hybrid CNN-LSTM model for diagnosing rice nutrient levels at the rice panicle initiation stage
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作者 Fubing Liao Xiangqian Feng +6 位作者 Ziqiu Li Danying Wang Chunmei Xu Guang Chu Hengyu Ma Qing Yao Song Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期711-723,共13页
Nitrogen(N)and potassium(K)are two key mineral nutrient elements involved in rice growth.Accurate diagnosis of N and K status is very important for the rational application of fertilizers at a specific rice growth sta... Nitrogen(N)and potassium(K)are two key mineral nutrient elements involved in rice growth.Accurate diagnosis of N and K status is very important for the rational application of fertilizers at a specific rice growth stage.Therefore,we propose a hybrid model for diagnosing rice nutrient levels at the early panicle initiation stage(EPIS),which combines a convolutional neural network(CNN)with an attention mechanism and a long short-term memory network(LSTM).The model was validated on a large set of sequential images collected by an unmanned aerial vehicle(UAV)from rice canopies at different growth stages during a two-year experiment.Compared with VGG16,AlexNet,GoogleNet,DenseNet,and inceptionV3,ResNet101 combined with LSTM obtained the highest average accuracy of 83.81%on the dataset of Huanghuazhan(HHZ,an indica cultivar).When tested on the datasets of HHZ and Xiushui 134(XS134,a japonica rice variety)in 2021,the ResNet101-LSTM model enhanced with the squeeze-and-excitation(SE)block achieved the highest accuracies of 85.38 and 88.38%,respectively.Through the cross-dataset method,the average accuracies on the HHZ and XS134 datasets tested in 2022 were 81.25 and 82.50%,respectively,showing a good generalization.Our proposed model works with the dynamic information of different rice growth stages and can efficiently diagnose different rice nutrient status levels at EPIS,which are helpful for making practical decisions regarding rational fertilization treatments at the panicle initiation stage. 展开更多
关键词 dynamic model of deep learning UAV rice panicle initiation nutrient level diagnosis image classification
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Subsoil tillage enhances wheat productivity,soil organic carbon and available nutrient status in dryland fields
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作者 Qiuyan Yan Linjia Wu +6 位作者 Fei Dong Shuangdui Yan Feng Li Yaqin Jia Jiancheng Zhang Ruifu Zhang Xiao Huang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期251-266,共16页
Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nut... Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China. 展开更多
关键词 TILLAGE dryland wheat fields soil aggregate size soil nutrients soil carbon and nitrogen fractions
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Tracing the sources of nutrients through the Tsushima/Korea Strait
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作者 Jing Zhang Xinyu Guo +2 位作者 Lei Zhu Jianlong Feng Liang Zhao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期142-152,共11页
The nutrients from the East China Sea(ECS) through the Tsushima/Korea Strait(TS) strongly impact the eco system of the Japan Sea(JS).The complex origins of the Tsushima Warm Current and the various nutrient sources in... The nutrients from the East China Sea(ECS) through the Tsushima/Korea Strait(TS) strongly impact the eco system of the Japan Sea(JS).The complex origins of the Tsushima Warm Current and the various nutrient sources in the ECS result in complex spatial-temporal variations in nutrients in the TS.Using a physical-biological model with a tracking technique,we studied the effects of nutrient sources from the ECS on the TS.Among all the nutrient sources,the Kuroshio has the highest nutrient concentrations in the TS.Its maximum concentration occurs at the bottom,while those of rivers and atmospheric depo sition occur at the surface,and that of the Taiwan Strait occurs in the middle layer.The nutrient transport through the TS exhibits similar seasonal variations,as does the volume transport.The transport of nutrients from the Kuroshio accounts for more than 85% of the total.The transport of nutrients from the Taiwan Strait is greater during autumn and winter.The transport of dissolved inorganic nitrogen(DIN) from both rivers and atmospheric deposition through the TS peak in August.Nutrient transport cannot be equated with volume transport.The DIN in the less saline zone originates not only from rivers but also from atmospheric deposition and the Kuroshio.The transport of nutrients from the Taiwan Strait is not as significant as its volume transport in the TS. 展开更多
关键词 dissolved inorganic nitrogen dissolved inorganic phosphate East China Sea Japan Sea nutrient transport
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Rhizobium Inoculation and Micronutrient Addition Influence the Growth,Yield,Quality and Nutrient Uptake of Garden Peas(Pisum sativum L.)
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作者 MdAbdul Quddus MdAtaur Rahman +8 位作者 Razu Ahmed Mohammad Eyakub Ali Khokan Kumer Sarker MdAlamgir Siddiky Mohibur Rahman Lamya Ahmed Alkeridis Samy Sayed Ahmed Gaber Akbar Hossain 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期901-922,共22页
Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity ... Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in Bangladesh.Therefore,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden peas.Treatments were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)Mo1.All treatments were arranged in a randomized complete block design and repeated all treatments in three times.The application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over control.The same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden peas.Among all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and profitability.The results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden peas.The results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea. 展开更多
关键词 NODULATION nutrient content Pisum sativum L. PROFITABILITY RHIZOBIUM Zn B Mo
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Impact of sourdough fermentation on nutrient transformations in cereal-based foods:Mechanisms,practical applications,and health implications
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作者 Zhen Wang Luyang Wang 《Grain & Oil Science and Technology》 CAS 2024年第2期124-132,共9页
Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransfor... Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods. 展开更多
关键词 Sourdough fermentation Lactic acid bacteria PROTEOLYSIS Starch hydrolysis Low-GI nutrientS
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Unexpected Diversity in Ecosystem Nutrient Responses to Experimental Drought in Temperate Grasslands
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作者 Biying Qiu Niwu Te +8 位作者 Lin Song Yuan Shi Chuan Qiu Xiaoan Zuo Qiang Yu Jianqiang Qian Zhengwen Wang Honghui Wu Wentao Luo 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期831-841,共11页
The responses of ecosystem nitrogen (N) and phosphorus (P) to drought are an important component of globalchange studies. However, previous studies were more often based on site-specific experiments, introducing a sig... The responses of ecosystem nitrogen (N) and phosphorus (P) to drought are an important component of globalchange studies. However, previous studies were more often based on site-specific experiments, introducing a significantuncertainty to synthesis and site comparisons. We investigated the responses of vegetation and soil nutrientsto drought using a network experiment of temperate grasslands in Northern China. Drought treatment (66%reduction in growing season precipitation) was imposed by erecting rainout shelters, respectively, at the driest,intermediate, and wettest sites. We found that vegetation nutrient concentrations increased but soil nutrient concentrationsdecreased along the aridity gradient. Differential responses were observed under experimentaldrought among the three grassland sites. Specifically, the experimental drought did not change vegetation andsoil nutrient status at the driest site, while strongly reduced vegetation but increased soil nutrient concentrationsat the site with intermediate precipitation. On the contrary, experimental drought increased vegetation N concentrationsbut did not change vegetation P and soil nutrient concentrations at the wettest site. In general, the differentialeffects of drought on ecosystem nutrients were observed between manipulative and observationalexperiments as well as between sites. Our research findings suggest that conducting large-scale, consistent, andcontrolled network experiments is essential to accurately evaluate the effects of global climate change on terrestrialecosystem bio-geochemistry. 展开更多
关键词 Climate change drought experiment precipitation nutrient cycles
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Effect of dietary supplementation with discardednutrient medium of Cordyceps militaris on layingperformance and diversity of intestinal flora in laying hens
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作者 XU Fangxu ZHANG Jinying +2 位作者 LI Bingxin LIU Yefei WANG Ze 《沈阳师范大学学报(自然科学版)》 CAS 2024年第2期186-192,共7页
The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordy... The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 展开更多
关键词 Cordyceps militaris discarded nutrient medium drug susceptibility intestinal flora laying hens
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