Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine ...Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine Bangladesh,are generally low in organic matter status and deficient in necessary nutrient elements for crop production.Addressing this challenge,the present study was conducted to investigate the effects of various organic nutrient sources with inorganic fertilizers on crop yields,nutrient uptake,and soil fertility in farm(L1)and char land(L2)of Brahmaputra River in Mymensingh,Bangladesh from 2022(Y1)to 2023(Y2).For each location,eight treatments viz.T1(Control),T2[100%recommended fertilizer dose(RFD)],T3(75%RFD),T4(75%N from RFD 25%N from cow dung),T5(75%+N from RFD 25%N from poultry manure),T6(75%N from RFD 25%N from vermicompost),T7(75%N from++RFD 25%N from household compost)and T8(75%N from RFD 25%N from rice straw compost)were arranged in++a randomized complete block design with three replications using Wheat–Mungbean–T.Aman rice cropping pattern where three way interaction was considered for results.Treatment T5 performed the best in both years in both locations as it enhanced the yield components(p 0.05)and caused yield increment over control.The yield improvement in<Char land soils was higher than that in farm soils.For all three crops,treatment T5 consistently augmented the uptake of nitrogen,phosphorus,potassium,and sulphur by different parts of the crops and improved soil fertility properties such as organic matter status,cation exchange capacity,total nitrogen,available phosphorus,and sulphur as well as exchangeable potassium in both locations in both years.Cost and return analysis of different treatments for the whole cropping system showed that the highest marginal benefit-cost ratio(16.35 and 15.07)and gross return(about Tk 768,595/ha and 728,341/ha)were obtained from the T5 treatment in farm soils and Char land soils,respectively.Followed by poultry manure,vermicompost performed well in addition to mineral fertilizers for improving crop yield and soil fertility but its economic efficiency was less due to high input cost.These findings may be useful to the smallholder farmers in char areas,who could benefit from increased productivity,reduced reliance on chemical fertilizers,and improved soil health,contributing to the long-term sustainability of char land agriculture.展开更多
To better understand the effects of ground-level ozone(O_(3))on nutrients and stoichiometry in different plant organs,urban tree species Celtis sinensis,Cyclocarya paliu-rus,Quercus acutissima,and Quercus nuttallii we...To better understand the effects of ground-level ozone(O_(3))on nutrients and stoichiometry in different plant organs,urban tree species Celtis sinensis,Cyclocarya paliu-rus,Quercus acutissima,and Quercus nuttallii were sub-jected to a constant exposure to charcoal-filtered air(CF),nonfiltered air(NF),or NF+40,60,or 80 nmol O_(3)mol^(-1)(NF40,NF60,and NF80)starting early in the summer of the growing season.At the end of summer,net CO_(2)assimila-tion rate(A),stomatal conductance(gs),leaf mass per area(LMA),and/or leaf greenness(SPAD)either were not sig-nificantly affected by elevated O_(3)or were even higher in some cases during the summer compared with the CF or NF controls.LMA was significantly lower in autumn only after the highest O_(3)exposures.Compared to NF,NF40 caused a large increase in gs across species in late summer and more K and Mn in stems.At the end of the growing season,nutri-ent status and stoichiometric ratios in different organs were variously altered under O_(3)stress;many changes were large and often species-specific.Across O_(3)treatments,LMA was primarily associated with C and Mg levels in leaves and Ca levels in leaves and stems.NF40 enriched K,P,Fe,and Mn in stems,relative to NF,and NF60 enhanced Ca in leaves relative to CF and NF40.Moreover,NF resulted in a higher Ca/Mg ratio in leaves of Q.acutissima only,relative to the other O_(3)regimes.Interestingly,across species,O_(3)stress led to different nutrient modifications in different organs(stems+branches vs leaves).Thus,ambient and/or elevated O_(3)exposures can alter the dynamics and distribution of nutrients and disrupt stoichiometry in different organs in a species-specific manner.Changes in stoichiometry reflect an important defense mechanism in plants under O_(3),and O_(3)pollution adds more risk to ecological stoichiometries in urban areas.展开更多
Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially i...Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.展开更多
Background There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming,but these feedstuffs are fibrous in nature.This study investigated the relationship b...Background There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming,but these feedstuffs are fibrous in nature.This study investigated the relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization,energy metabolism,and gut microbiota in growing pigs.Methods Thirty-six growing barrows(47.2±1.5 kg)were randomly allotted to 6 dietary treatments with 2 apparent viscosity levels and 3β-glucan-to-arabinoxylan ratios.In the experiment,nutrient utilization,energy metabolism,fecal microbial community,and production and absorption of short-chain fatty acid(SCFA)of pigs were investigated.In vitro digestion and fermentation models were used to compare the fermentation characteristics of feedstuffs and ileal digesta in the pig’s hindgut.Results The production dynamics of SCFA and dry matter corrected gas production of different feedstuffs during in vitro fermentation were different and closely related to the physical properties and chemical structure of the fiber.In animal experiments,increasing the dietary apparent viscosity and theβ-glucan-to-arabinoxylan ratios both increased the apparent ileal digestibility(AID),apparent total tract digestibility(ATTD),and hindgut digestibility of fiber components while decreasing the AID and ATTD of dry matter and organic matter(P<0.05).In addition,increasing dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased gas exchange,heat production,and protein oxidation,and decreased energy deposition(P<0.05).The dietary apparent viscosity andβ-glucanto-arabinoxylan ratios had linear interaction effects on the digestible energy,metabolizable energy,retained energy(RE),and net energy(NE)of the diets(P<0.05).At the same time,the increase of dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased SCFA production and absorption(P<0.05).Increasing the dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios increased the diversity and abundance of bacteria(P<0.05)and the relative abundance of beneficial bacteria.Furthermore,increasing the dietaryβ-glucan-to-arabinoxylan ratios led to a linear increase in SCFA production during the in vitro fermentation of ileal digesta(P<0.001).Finally,the prediction equations for RE and NE were established.Conclusion Dietary fiber physicochemical properties alter dietary fermentation patterns and regulate nutrient utilization,energy metabolism,and pig gut microbiota composition and metabolites.展开更多
To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conduct...To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before harvest.The appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of storage.The results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli color.Furthermore,during the growth stage,total sugar accumulation was higher in the 5-ARG group.In addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest broccoli.In conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of broccoli.Therefore,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.展开更多
Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of ...Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of sodium selenite(Na2SeO3),nanoparticles(SeNPs)and microparticles(SeMPs)of Se in cucumber seedlings,via two experiments:one with seed priming and the other with foliar application of Sematerials.The doses used were:0,0.1,0.5,1.0,1.5 and 3.0 mg⋅L^(−1),for each form of Se and for each form of application.Treatment 0 consisted of the application of distilled water,which was used as a control.The results indicated that the SeMPs treatment at 3.0 mg⋅L^(−1)for seed priming had the greatest effect on stem diameter and leaf area.Foliar application of SeMPs at 1.5 mg⋅L^(−1)was the most effective at increasing the leaf area.In terms of fresh and dry biomass(aerial,root and total)for seed priming,all the treatments were superior to the control,and SeMPs at 1.5 and 3.0 mg⋅L^(−1)caused the greatest effects.With foliar application,fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg⋅L^(−1),and dry biomass(aerial,root and total)increased with the SeMPs at 1.0 and 3.0 mg⋅L^(−1).With respect to the photosynthetic pigments,proteins,phenols and minerals,the Se treatments,both for seed priming and foliar application,caused increases and decreases;however,reduced glutathione(GSH)increased with treatments in both forms of application.The Se concentration in the seedlings increased as the dose of Se material increased,and greater accumulation was achieved with foliar application of SeNPs and SeMPs.The results indicate that the use of Se materials is recommended,mainly the use of SeMPs,which improved the variables studied.This opens new opportunities for further studies with SeMPs,as little information is available on their application in agricultural crops.展开更多
A field trial to evaluate the growth and nutrient uptake of cocoa intercropped with coconut was conducted in Cocoa Research Institute of Nigeria(CRIN)Headquarters,Idi-Ayunre,Ibadan,Oyo State between 2019 and 2022.Ther...A field trial to evaluate the growth and nutrient uptake of cocoa intercropped with coconut was conducted in Cocoa Research Institute of Nigeria(CRIN)Headquarters,Idi-Ayunre,Ibadan,Oyo State between 2019 and 2022.There were four treatments comprising of cocoa sole,cocoa/plantain,cocoa/coconut and cocoa/coconut/plantain intercrop.The experimental design was Randomized Complete Block(RCB)replicated three times.Result obtained showed that cocoa/plantain was significantly higher(p<0.05)than all other treatments in all parameters considered and closely followed by cocoa/coconut,then cocoa sole with cocoa/plantain/coconut giving the least performance.The same trend was observed in the nutrient uptake.It was also observed in the trial that the two crops:cocoa and coconut did not show any deleterious effect on their growth when intercropped together.This showed that the two crops are compatible when grown on the same piece of land.Therefore,cocoa/coconut intercrop could be recommended to cocoa farmers in south west Nigeria to increase their revenue generation when coconut starts bearing fruit instead of sole planting of cocoa.展开更多
Afforestation on formerly cultivated or aban-doned agricultural land is a common strategy to increase forest areas and enhance carbon sequestration.Deep soil ploughing before afforestation improves soil conditions,fac...Afforestation on formerly cultivated or aban-doned agricultural land is a common strategy to increase forest areas and enhance carbon sequestration.Deep soil ploughing before afforestation improves soil conditions,facilitating tree growth and carbon storage.This study assessed the growth and biomass parameters of Pinus sylves-tris in 10-and 20 years old plantations established on deeply ploughed and non-ploughed soils in Lithuania.Biomass allocation and carbon and nutrient concentrations including N,P,K,Ca and Mg were analysed in aboveground biomass components.Deep ploughing in the 10 years old stands negatively impacted vertical growth and stem development but did not significantly affect overall biomass accumula-tion.In contrast,in the 20 years old stands,deep plough-ing resulted in taller trees with larger diameters and higher biomass accumulation compared to non-ploughed sites.Biomass distribution within tree canopies varied between ploughed and non-ploughed sites,indicating diverse effects of deep ploughing.Carbon and nutrient concentrations in biomass components showed site-specific variations,with deep ploughing influencing carbon concentrations in needles and stem bark.Overall,deep ploughing showed potential for enhancing tree growth and biomass accumulation,with implications for carbon sequestration in forest ecosystems.These findings help us understand the impact of an alternative soil management practice,deep ploughing,on forest development and carbon dynamics.展开更多
Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation.However,studies on t...Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation.However,studies on the effects of processive oxidative stress on nutrient transport in the placenta have received little attention.The present study was conducted on sows at 85 days of gestation to study the effects of pterostilbene(PTE)on maternal oxidative stress status and placental nutrient transport.Results PTE increased the antioxidant capacity and immunoglobulin content in mothers’blood and milk,reduced the level of inflammatory factors,and improved the nutrient content of milk.PTE also reduced sow backfat loss and the number of weak sons,and increased piglet weaning weight and total weaning litter weight.We subsequently found that PTE enhanced placental glucose and fatty acid transport and further affected glycolipid metabolism by increasing the expression of LAL,PYGM,and Gbe-1,which activated the PI3K phosphorylation pathway.Moreover,PTE addition altered the relative abundance of the Firmicutes,Proteobacteria,Parabacillus,and Bacteroidetes-like RF16 groups in sow faeces.PTE increased the levels of acetate,propionate,butyrate and isovalerate in the faeces.Conclusions These findings reveal that the addition of PTE during pregnancy and lactation mitigates the effects of processive oxidative stress on offspring development by altering maternal microbial and placental nutrient trans-port capacity.展开更多
The degradation of animal carcasses can lead to rapid waste release(e.g.,pathogenic bacteria,viruses,prions,or parasites)and also result in nutrient accumulation in the surrounding environment.However,how viral profil...The degradation of animal carcasses can lead to rapid waste release(e.g.,pathogenic bacteria,viruses,prions,or parasites)and also result in nutrient accumulation in the surrounding environment.However,how viral profile responds and influences nutrient pool(carbon(C),nitrogen(N),phosphorus(P)and sulfur(S))in polluted water caused by animal carcass decomposition had not been explored.Here,we combined metagenomic analysis,16S rRNA gene sequencing and water physicochemical assessment to explore the response of viral communities under different temperatures(23℃,26℃,29℃,32℃,and 35℃)in water polluted by cadaver,as well as compare the contribution of viral/bacterial communities on water nutrient pool.We found that a total of 15,240 viral species were classified and mainly consisted of Siphoviridae.Both temperature and carrion reduced the viral diversity and abundance.Only a small portion of the viruses(∼8.8%)had significant negative correlations with temperature,while most were not sensitive.Our results revealed that the viruses had lager contribution on nutrient pool than bacteria.Besides,viral-related functional genes involved in C,N,P and S cycling.These functional genes declined during carcass decomposition and covered part of the central nutrient cycle metabolism(including carbon sugar transformation,denitrification,P mineralization and extracelluar sulfate transfer,etc.).Our result implies that human regulation of virus communities may be more important than bacterial communities in regulating and managing polluted water quality and nutrition.展开更多
Tropical coastal ecosystems,vital habitats for economically significant marine species,face increasing threats from eutrophication driven by human-induced nutrient pollution.This study investigated the metabolomic pro...Tropical coastal ecosystems,vital habitats for economically significant marine species,face increasing threats from eutrophication driven by human-induced nutrient pollution.This study investigated the metabolomic profile of Anadara granosa,a marine bivalve,to identify metabolites indicative of eutrophic conditions.Conducted in Cirebon Bay,Indonesia,the research spanned five locations reflecting varying eutrophication levels.Bottom-layer water samples were analyzed for pH,dissolved oxygen,salinity,water transparency,and nutrient concentrations(phosphate,nitrate,ammonia).Proton-Nuclear Magnetic Resonance(Proton-NMR)metabolomics of A.granosa revealed metabolite variations linked to water quality.Eutrophic conditions,prevalent in the bay’s northern side,were characterized by inorganic nitrogen levels above 0.2 mg L^(-1) and phosphate exceeding 0.024 mg L^(-1).These were linked to urban,aquaculture,and agricultural runoff,driving increased phytoplankton biomass and reduced salinity variability.Metabolomic analysis identified inosine and dimethylglycine as potential biomarkers.Elevated inosine levels in eutrophic environments suggest increased cellular activity due to greater food availability,while higher dimethylglycine concentrations detected in low-nutrient as its role in osmotic regulation.Both metabolites correlated with ammonia concentrations(P<0.05,R^(2)=0.631),a key contributor to eutrophication.These findings highlight inosine and dimethylglycine as effective indicators of nutrient enrichment,providing insights into eutrophication’s impact on coastal ecosystems and A.granosa’s physiological responses.展开更多
Interaction between the Yangtze River and its tributaries in the Three Gorges Reservoir has an important influence on tributary algal blooms.Taking the Xiaojiang River as a typical tributary,a binary mixing model used...Interaction between the Yangtze River and its tributaries in the Three Gorges Reservoir has an important influence on tributary algal blooms.Taking the Xiaojiang River as a typical tributary,a binary mixing model used stable isotopes of hydrogen and oxygen to quantitatively analyze the water contribution and nutrient source structure of the tributary backwater area.Results showed that the isotope content(δD:−54.7‰,δ^(18)O−7.8‰)in the Yangtze River was higher than that in the tributaries(δD:−74.2‰,δ^(18)O−17.0‰)in the non-flood season and lower than that in the tributaries in the flood season.The Yangtze River contributed more than 50%water volume of the tributary backwater area in the non-flood season.The total nitrogen and total phosphorus concentrations in the backwater area were estimated based on water contribution ratio,and the results were in good agreement with the monitoring results.Load estimation showed that the nitrogen and phosphorus contribution ratio of the Yangtze River to the tributary backwater area was approximately 40%-80%in the non-flood season,and approximately 20%-40%in the flood season,on average.This study showed that the interaction between the Xiaojiang River and the Yangtze River is significant,and that Yangtze River recharge is an important source of nutrients in the Xiaojiang backwater area,which may play a driving role in Xiaojiang River algal blooms.展开更多
Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is sti...Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is still unclear,partly due to lack of data spanning the entire summer.In this study,nitrate,phosphate,and silicate combined with temperature,salinity,and apparent oxygen utilization(AOU)were analyzed along 45°E in the Cosmonaut Sea during December 2019,January 2021,and February 2022.The variations in nutrient utilization in the euphotic layer were studied using biogeochemical tracers,and seasonal nutrient depletion was also estimated.The results showed that nutrient distribution varied significantly from December to February.Significant positive correlations were observed for nitrate and silicate concentrations with salinity and AOU,indicating that nutrient distributions were mainly influenced by water mass and phytoplankton production.Increasing∆[N*]and decreasing∆[Si*]in the upper 50 m were observed south of 63.5°S from December to February,which possibly contributed to a progressive shift in dominant phytoplankton population from Phaeocystis antarctica to diatoms.The seasonal nutrient depletion generally increased from December to February.Moreover,the consumption of silicate substantially increased compared to nitrate,indicating that the abundance of diatoms was increasing with time during the austral summer.Our observations suggest that nutrient utilization status is closely related to phytoplankton community structure in the euphotic layer of the Cosmonaut Sea.展开更多
Diet and nutrition significantly influence health, largely by regulating intestinalnutrient absorption. The intestinal epithelium, as the primary site for nutrientuptake, undergoes continuous renewal driven by precise...Diet and nutrition significantly influence health, largely by regulating intestinalnutrient absorption. The intestinal epithelium, as the primary site for nutrientuptake, undergoes continuous renewal driven by precise regulation of intestinalstem cells (ISCs). Nutrient sensing and metabolism are key determinants of ISCfate, making ISCs a central link between nutrient metabolism and the regulationof intestinal tissue renewal and homeostasis. Understanding how ISCs respond ormake adaptations to nutritional signals is therefore vital for maintaining intestinalhomeostasis. Recent studies have spotlighted the origin and identity of ISCs andbroadened our insight into the plasticity and function of ISCs under differentconditions. Mitochondria, the central hubs of energy production and metabolicsignals provided by dietary components and metabolic substrates, such as glucose,amino acids, and lipids, govern the intricate balance between self-renewal anddifferentiation of ISCs. This review highlights the importance of nutrient sensing,metabolic regulation, and mitochondrial function in the specification of ISC fate.A thorough understanding of these mechanisms paves the way for the developmentof stem cell-based therapy for the mucosal healing of gastrointestinaldiseases and diet intervention to foster body health.展开更多
Deprivation of glucose and lactate provides an effective pathway to terminate the nutrients supplement for tumor growth.In this work,biomimetic nanozymes called m@BGLC are constructed for catalytic tumor inhibition th...Deprivation of glucose and lactate provides an effective pathway to terminate the nutrients supplement for tumor growth.In this work,biomimetic nanozymes called m@BGLC are constructed for catalytic tumor inhibition through nutrients deprivation and oxidative damage induction.Concretely,the catalytic enzymes of glucose oxidase(GOx),lactate oxidase(LOx)and chloroperoxidase(CPO)are precrosslinked with bovine serum albumin(BSA)to construct nanozymes,which are then biomimetic functionalized with cancer cell membrane to prepare m@BGLC.Benefiting from the biomimetic camouflage with homologous cell membrane,m@BGLC inherit homotypic binding and immune escape abilities,facilitating the tumor targeting accumulation and preferable cell internalization for improved drug delivery efficiency.Subsequently,under the cascade catalysis of nanozymes,m@BGLC consume glucose and lactate for tumor starvation therapy through nutrients deprivation,and meanwhile,the resulting hyprochloric acid(HClO)causes an oxidative damage of cells to synergistically inhibit tumor growth.In vitro and in vivo findings demonstrate a robust tumor eradication effect of m@BGLC without obvious adverse reactions via the targeted combination therapy.Such cascade catalytic nanomedicine may inspire the development of sophisticated strategies for tumor combination therapy under unfavorable tumor microenvironments.展开更多
Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the p...Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the publisher's production process.The published incorrect version and the corrected version of Fig.4 are given below.展开更多
The study determined the carbon stocks and litter nutrient concentration in tropical forests along the ecological gradient in Kenya.This could help understand the potential of mitigating climate change using tropical ...The study determined the carbon stocks and litter nutrient concentration in tropical forests along the ecological gradient in Kenya.This could help understand the potential of mitigating climate change using tropical forest ecosystems in different ecological zones,which are being affected by climate change to a level that they are becoming carbon sources instead of sinks.Stratified sampling technique was used to categorize tropical forests into rain,moist deciduous and dry zone forests depending on the average annual rainfall received.Simple random sampling technique was used to select three tropical forests in each category.Modified consistent sampling technique was used to develop 10 main 20 m×100 m plots in each forest,with 202 m×50 m sub-plots in each plot.Systematic random sampling technique was used in selecting 10 sub-plots from each main plot for inventory study.Non-destructive approach based on allometric equations using trees’diameter at breast height(DBH),total height and species’wood specific gravity were used in estimating tree carbon stock in each forest.Soil organic carbon(SOC)and litter nutrient concentration(total phosphorus and nitrogen)were determined in each forest based on standard laboratory procedures.The results indicated that,whilst trees in rain forests recorded a significantly higher(p<0.001)DBH(20.36 cm)and total tree height(12.1 m),trees in dry zone forests recorded a significantly higher(p<0.001)specific gravity(0.67 kg m^(−3)).Dry zone tropical forests stored a significantly lower amount of total tree carbon of 73 Mg ha^(−1),compared to tropical rain forests(439.5 Mg ha^(−1))and moist deciduous tropical forests(449 Mg ha^(−1)).The SOC content was significantly higher in tropical rainforests(3.9%),compared to soils from moist deciduous(2.9%)and dry zone forests(1.8%).While litter from tropical rain forests recorded a significantly higher amount of total nitrogen(3.4%),litter from dry zone forests recorded a significantly higher concentration of total phosphorus(0.27%).In conclusion,ecological gradient that is dictated by the prevailing temperatures and precipitation affects the tropical forests carbon stock potential and litter nutrient concentration.This implies that,the changing climate is having a serious implication on the ecosystem services such as carbon stock and nutrients cycling in tropical forests.展开更多
Cyanobacterial blooms,exacerbated by climate change and eutrophication,increasingly compromise water quality by producing taste and odor(T&O)compounds including 2-methylisoborneol(MIB).Cyanobacteria synthesize MIB...Cyanobacterial blooms,exacerbated by climate change and eutrophication,increasingly compromise water quality by producing taste and odor(T&O)compounds including 2-methylisoborneol(MIB).Cyanobacteria synthesize MIB by redirecting carbon metabolism intermediates into the methylerythritol phosphate pathway.This process appears to be influenced by rising atmospheric CO_(2) partial pressure(pCO_(2)).This study examines how elevated pCO_(2) affects MIB production in Synechococcus sp.FACHB-1061 under varying nutrient conditions.The results indicate that elevated pCO_(2) boosts cyanobacterial biomass and total MIB yield,particularly in nutrient-rich environments,by reducing limitations in bioavailable inorganic carbon.In contrast,in nutrient-limited conditions,both total MIB concentration and per-cell production significantly increased with higher pCO_(2).Elevated pCO_(2) altered the activities of nitrate reductase and carbonic anhydrase,reducing impaired nitrogen assimilation and enhanced carbon fixation.The increase and compositional changes in extracellular polymeric substances suggested carbon overflow and a decline in cellular quality under insufficient nutrients.Additionally,markers of oxidative stress,such as increased superoxide dismutase activity and higher malondialdehyde levels,suggested that oxidative stress might stimulate secondary metabolite production.Metabolomic analysis revealed that critical intermediates of the Calvin cycle and glycolysis,such as glyceraldehyde-3-phosphate and acetyl-CoA,were upregulated with elevated pCO_(2) in nutrient-limited status,leading to increase of key precursors for MIB.These results highlight the complex interplay between nutrient and rising pCO_(2) in regulating cyanobacterial MIB biosynthesis.The findings suggest that conventional nutrient control strategies for mitigating cyanobacterial blooms and associated T&O issues may need reassessment under future climate scenarios.展开更多
Biochar and animal manure application can improve crop yields in salt-affected soil.Previous studies have primarily applied biochar and animal manure either alone or at fixed ratios,while their combined effects with v...Biochar and animal manure application can improve crop yields in salt-affected soil.Previous studies have primarily applied biochar and animal manure either alone or at fixed ratios,while their combined effects with varying combination proportions are still unclear.To address this knowledge gap,we performed a 2-a experiment(2023-2024)in a salinized cotton field in Wensu County of Xinjiang Uygur Autonomous Region of China with the following 6 treatments:control;application of biochar(10t/hm^(2))alone(BC100%);application of cow manure(10 t/hm^(2))alone(CM100%);application of 70%biochar(7 t/hm^(2))combined with 30%cow manure(3 t/hm^(2))(BC70%+CM30%);application of 50%biochar(5 t/hm^(2))combined with 50%cow manure(5 t/hm^(2))(BC50%+CM50%);and application of 30%biochar(3 t/hm^(2))combined with 70%cow manure(7 t/hm^(2))(BC30%+CM70%).By measuring soil pH,electrical conductivity,soil organic matter,available phosphorus,available potassium,and available nitrogen at 0-20 and 20-40 cm depths,as well as yield components and cotton yield in 2023 and 2024,this study revealed that soil nutrients in the 0-20 cm depth were more sensitive to the treatment.Among all the treatments,BC50%+CM50%treatment had the highest value of soil pH(9.63±0.07)but the lowest values of electrical conductivity(161.9±31.8μS/cm),soil organic matter(1.88±0.27 g/kg),and available potassium(42.72±8.25 mg/kg)in 2024.Moreover,the highest cotton yield(5336.63±467.72 kg/hm^(2))was also observed under BC50%+CM50%treatment in 2024,which was 1.9 times greater than that under the control treatment.In addition,cotton yield in 2023 was jointly determined by yield components(density and number of cotton bolls)and soil nutrients(available phosphorus and available potassium),but in 2024,cotton yield was only positively related to yield components(density,number of cotton bolls,and single boll weight).Overall,this study highlighted that in salt-affected soil,the combination of biochar and cow manure at a 1:1 ratio is recommended for increasing cotton yield and reducing soil salinity stress.展开更多
The exchange of inorganic nutrients at the coastal sediment-water interface(SWI)plays a crucial role in regulating the nutrient budget in overlying water.The related studies mainly focus on the mid-to high-latitude re...The exchange of inorganic nutrients at the coastal sediment-water interface(SWI)plays a crucial role in regulating the nutrient budget in overlying water.The related studies mainly focus on the mid-to high-latitude regions,leaving a significant gap in the quantitative assessment of nutrient exchange and environmental controls at the SWI in lowlatitude coastal regions.We quantitatively assess the exchange of inorganic nutrients at the SWI in three tropical bays(Dongzhai Harbor,Xiaohai Lagoon,Qinglan Harbor).Sediments act as a source of ammonium,phosphate,and silicate,but for nitrate,sediments can be both a source and sink,although with substantial spatial and temporal variations in their fluxes.Labile organic matter is a critical regulator for the fluxes of inorganic nutrients at the SWI.The sedimentary nutrients input with high N/P molar ratio will alter the nutrient stoichiometry to mitigate the nitrogen limitation in coastal waters.However,the internal sediment release in these tropical bays plays a relative weak role in contributing to the nutrient addition in comparison with the other external nutrient sources including riverine input,submarine groundwater discharge,and atmospheric deposition.According to the global compilation on SWI nutrient fluxes,we propose that water column primary production and external inputs to interpret the variation in exchange and fluxes of nutrients at the SWI in different ecosystems.Such a conceptual understanding of these chain biogeochemical processes involving external nutrient input,primary production,particulate organic matter settling,and the accumulation and release of inorganic nutrients in sediments will be helpful for the scientific-based pollution prevent and control in coastal waters.展开更多
基金funded by Taif University,Saudi Arabia,Project No.(TU-DSPP-2025-30)The Science and Technology Fellowship Trust(SL No.39.00.0000.035.22.013.19.144)under the Ministry of Science and Technology of Bangladesh partially financed the current research。
文摘Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture.Char land soils,widely distributed in riverine Bangladesh,are generally low in organic matter status and deficient in necessary nutrient elements for crop production.Addressing this challenge,the present study was conducted to investigate the effects of various organic nutrient sources with inorganic fertilizers on crop yields,nutrient uptake,and soil fertility in farm(L1)and char land(L2)of Brahmaputra River in Mymensingh,Bangladesh from 2022(Y1)to 2023(Y2).For each location,eight treatments viz.T1(Control),T2[100%recommended fertilizer dose(RFD)],T3(75%RFD),T4(75%N from RFD 25%N from cow dung),T5(75%+N from RFD 25%N from poultry manure),T6(75%N from RFD 25%N from vermicompost),T7(75%N from++RFD 25%N from household compost)and T8(75%N from RFD 25%N from rice straw compost)were arranged in++a randomized complete block design with three replications using Wheat–Mungbean–T.Aman rice cropping pattern where three way interaction was considered for results.Treatment T5 performed the best in both years in both locations as it enhanced the yield components(p 0.05)and caused yield increment over control.The yield improvement in<Char land soils was higher than that in farm soils.For all three crops,treatment T5 consistently augmented the uptake of nitrogen,phosphorus,potassium,and sulphur by different parts of the crops and improved soil fertility properties such as organic matter status,cation exchange capacity,total nitrogen,available phosphorus,and sulphur as well as exchangeable potassium in both locations in both years.Cost and return analysis of different treatments for the whole cropping system showed that the highest marginal benefit-cost ratio(16.35 and 15.07)and gross return(about Tk 768,595/ha and 728,341/ha)were obtained from the T5 treatment in farm soils and Char land soils,respectively.Followed by poultry manure,vermicompost performed well in addition to mineral fertilizers for improving crop yield and soil fertility but its economic efficiency was less due to high input cost.These findings may be useful to the smallholder farmers in char areas,who could benefit from increased productivity,reduced reliance on chemical fertilizers,and improved soil health,contributing to the long-term sustainability of char land agriculture.
基金supported by the National Natural Science Foundation of China(NSFC)(No.42107299).
文摘To better understand the effects of ground-level ozone(O_(3))on nutrients and stoichiometry in different plant organs,urban tree species Celtis sinensis,Cyclocarya paliu-rus,Quercus acutissima,and Quercus nuttallii were sub-jected to a constant exposure to charcoal-filtered air(CF),nonfiltered air(NF),or NF+40,60,or 80 nmol O_(3)mol^(-1)(NF40,NF60,and NF80)starting early in the summer of the growing season.At the end of summer,net CO_(2)assimila-tion rate(A),stomatal conductance(gs),leaf mass per area(LMA),and/or leaf greenness(SPAD)either were not sig-nificantly affected by elevated O_(3)or were even higher in some cases during the summer compared with the CF or NF controls.LMA was significantly lower in autumn only after the highest O_(3)exposures.Compared to NF,NF40 caused a large increase in gs across species in late summer and more K and Mn in stems.At the end of the growing season,nutri-ent status and stoichiometric ratios in different organs were variously altered under O_(3)stress;many changes were large and often species-specific.Across O_(3)treatments,LMA was primarily associated with C and Mg levels in leaves and Ca levels in leaves and stems.NF40 enriched K,P,Fe,and Mn in stems,relative to NF,and NF60 enhanced Ca in leaves relative to CF and NF40.Moreover,NF resulted in a higher Ca/Mg ratio in leaves of Q.acutissima only,relative to the other O_(3)regimes.Interestingly,across species,O_(3)stress led to different nutrient modifications in different organs(stems+branches vs leaves).Thus,ambient and/or elevated O_(3)exposures can alter the dynamics and distribution of nutrients and disrupt stoichiometry in different organs in a species-specific manner.Changes in stoichiometry reflect an important defense mechanism in plants under O_(3),and O_(3)pollution adds more risk to ecological stoichiometries in urban areas.
文摘Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.
基金supported by the National Key Research and Development Program(No.2021YFD1300201)Jilin Provincial Department of Science and Technology Innovation Platform and Talent Special Project(No.20230508090RC).
文摘Background There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming,but these feedstuffs are fibrous in nature.This study investigated the relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization,energy metabolism,and gut microbiota in growing pigs.Methods Thirty-six growing barrows(47.2±1.5 kg)were randomly allotted to 6 dietary treatments with 2 apparent viscosity levels and 3β-glucan-to-arabinoxylan ratios.In the experiment,nutrient utilization,energy metabolism,fecal microbial community,and production and absorption of short-chain fatty acid(SCFA)of pigs were investigated.In vitro digestion and fermentation models were used to compare the fermentation characteristics of feedstuffs and ileal digesta in the pig’s hindgut.Results The production dynamics of SCFA and dry matter corrected gas production of different feedstuffs during in vitro fermentation were different and closely related to the physical properties and chemical structure of the fiber.In animal experiments,increasing the dietary apparent viscosity and theβ-glucan-to-arabinoxylan ratios both increased the apparent ileal digestibility(AID),apparent total tract digestibility(ATTD),and hindgut digestibility of fiber components while decreasing the AID and ATTD of dry matter and organic matter(P<0.05).In addition,increasing dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased gas exchange,heat production,and protein oxidation,and decreased energy deposition(P<0.05).The dietary apparent viscosity andβ-glucanto-arabinoxylan ratios had linear interaction effects on the digestible energy,metabolizable energy,retained energy(RE),and net energy(NE)of the diets(P<0.05).At the same time,the increase of dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios both increased SCFA production and absorption(P<0.05).Increasing the dietary apparent viscosity andβ-glucan-to-arabinoxylan ratios increased the diversity and abundance of bacteria(P<0.05)and the relative abundance of beneficial bacteria.Furthermore,increasing the dietaryβ-glucan-to-arabinoxylan ratios led to a linear increase in SCFA production during the in vitro fermentation of ileal digesta(P<0.001).Finally,the prediction equations for RE and NE were established.Conclusion Dietary fiber physicochemical properties alter dietary fermentation patterns and regulate nutrient utilization,energy metabolism,and pig gut microbiota composition and metabolites.
文摘To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before harvest.The appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of storage.The results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli color.Furthermore,during the growth stage,total sugar accumulation was higher in the 5-ARG group.In addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest broccoli.In conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of broccoli.Therefore,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.
文摘Selenium(Se)is a nutrient that is considered beneficial for plants,because its improvement in growth,yield and quality helps plants to mitigate stress.The objective of this research was to evaluate the application of sodium selenite(Na2SeO3),nanoparticles(SeNPs)and microparticles(SeMPs)of Se in cucumber seedlings,via two experiments:one with seed priming and the other with foliar application of Sematerials.The doses used were:0,0.1,0.5,1.0,1.5 and 3.0 mg⋅L^(−1),for each form of Se and for each form of application.Treatment 0 consisted of the application of distilled water,which was used as a control.The results indicated that the SeMPs treatment at 3.0 mg⋅L^(−1)for seed priming had the greatest effect on stem diameter and leaf area.Foliar application of SeMPs at 1.5 mg⋅L^(−1)was the most effective at increasing the leaf area.In terms of fresh and dry biomass(aerial,root and total)for seed priming,all the treatments were superior to the control,and SeMPs at 1.5 and 3.0 mg⋅L^(−1)caused the greatest effects.With foliar application,fresh root biomass improved to a greater extent with the SeMPs treatment at 3.0 mg⋅L^(−1),and dry biomass(aerial,root and total)increased with the SeMPs at 1.0 and 3.0 mg⋅L^(−1).With respect to the photosynthetic pigments,proteins,phenols and minerals,the Se treatments,both for seed priming and foliar application,caused increases and decreases;however,reduced glutathione(GSH)increased with treatments in both forms of application.The Se concentration in the seedlings increased as the dose of Se material increased,and greater accumulation was achieved with foliar application of SeNPs and SeMPs.The results indicate that the use of Se materials is recommended,mainly the use of SeMPs,which improved the variables studied.This opens new opportunities for further studies with SeMPs,as little information is available on their application in agricultural crops.
文摘A field trial to evaluate the growth and nutrient uptake of cocoa intercropped with coconut was conducted in Cocoa Research Institute of Nigeria(CRIN)Headquarters,Idi-Ayunre,Ibadan,Oyo State between 2019 and 2022.There were four treatments comprising of cocoa sole,cocoa/plantain,cocoa/coconut and cocoa/coconut/plantain intercrop.The experimental design was Randomized Complete Block(RCB)replicated three times.Result obtained showed that cocoa/plantain was significantly higher(p<0.05)than all other treatments in all parameters considered and closely followed by cocoa/coconut,then cocoa sole with cocoa/plantain/coconut giving the least performance.The same trend was observed in the nutrient uptake.It was also observed in the trial that the two crops:cocoa and coconut did not show any deleterious effect on their growth when intercropped together.This showed that the two crops are compatible when grown on the same piece of land.Therefore,cocoa/coconut intercrop could be recommended to cocoa farmers in south west Nigeria to increase their revenue generation when coconut starts bearing fruit instead of sole planting of cocoa.
基金supported by the Long-term Research Programme“Sustainable Forestry and Global Changes”,conducted by the Lithuanian Research Centre for Agriculture and Forestry(LAMMC).
文摘Afforestation on formerly cultivated or aban-doned agricultural land is a common strategy to increase forest areas and enhance carbon sequestration.Deep soil ploughing before afforestation improves soil conditions,facilitating tree growth and carbon storage.This study assessed the growth and biomass parameters of Pinus sylves-tris in 10-and 20 years old plantations established on deeply ploughed and non-ploughed soils in Lithuania.Biomass allocation and carbon and nutrient concentrations including N,P,K,Ca and Mg were analysed in aboveground biomass components.Deep ploughing in the 10 years old stands negatively impacted vertical growth and stem development but did not significantly affect overall biomass accumula-tion.In contrast,in the 20 years old stands,deep plough-ing resulted in taller trees with larger diameters and higher biomass accumulation compared to non-ploughed sites.Biomass distribution within tree canopies varied between ploughed and non-ploughed sites,indicating diverse effects of deep ploughing.Carbon and nutrient concentrations in biomass components showed site-specific variations,with deep ploughing influencing carbon concentrations in needles and stem bark.Overall,deep ploughing showed potential for enhancing tree growth and biomass accumulation,with implications for carbon sequestration in forest ecosystems.These findings help us understand the impact of an alternative soil management practice,deep ploughing,on forest development and carbon dynamics.
基金Natural Science Foundation of Heilongjiang Province(YQ2022C014)National Natural Science Foundation of China(32302768).
文摘Background Progressive oxidative stress easily occurs as a result of a gradual increase in the intensity of maternal metabolism due to rapid foetal development and increased intensity of lactation.However,studies on the effects of processive oxidative stress on nutrient transport in the placenta have received little attention.The present study was conducted on sows at 85 days of gestation to study the effects of pterostilbene(PTE)on maternal oxidative stress status and placental nutrient transport.Results PTE increased the antioxidant capacity and immunoglobulin content in mothers’blood and milk,reduced the level of inflammatory factors,and improved the nutrient content of milk.PTE also reduced sow backfat loss and the number of weak sons,and increased piglet weaning weight and total weaning litter weight.We subsequently found that PTE enhanced placental glucose and fatty acid transport and further affected glycolipid metabolism by increasing the expression of LAL,PYGM,and Gbe-1,which activated the PI3K phosphorylation pathway.Moreover,PTE addition altered the relative abundance of the Firmicutes,Proteobacteria,Parabacillus,and Bacteroidetes-like RF16 groups in sow faeces.PTE increased the levels of acetate,propionate,butyrate and isovalerate in the faeces.Conclusions These findings reveal that the addition of PTE during pregnancy and lactation mitigates the effects of processive oxidative stress on offspring development by altering maternal microbial and placental nutrient trans-port capacity.
基金supported by the National Natural Science Foundation of China (No.42007026)the Medical Innovation and Development Project of Lanzhou University (lzuyxcx-2022-172)
文摘The degradation of animal carcasses can lead to rapid waste release(e.g.,pathogenic bacteria,viruses,prions,or parasites)and also result in nutrient accumulation in the surrounding environment.However,how viral profile responds and influences nutrient pool(carbon(C),nitrogen(N),phosphorus(P)and sulfur(S))in polluted water caused by animal carcass decomposition had not been explored.Here,we combined metagenomic analysis,16S rRNA gene sequencing and water physicochemical assessment to explore the response of viral communities under different temperatures(23℃,26℃,29℃,32℃,and 35℃)in water polluted by cadaver,as well as compare the contribution of viral/bacterial communities on water nutrient pool.We found that a total of 15,240 viral species were classified and mainly consisted of Siphoviridae.Both temperature and carrion reduced the viral diversity and abundance.Only a small portion of the viruses(∼8.8%)had significant negative correlations with temperature,while most were not sensitive.Our results revealed that the viruses had lager contribution on nutrient pool than bacteria.Besides,viral-related functional genes involved in C,N,P and S cycling.These functional genes declined during carcass decomposition and covered part of the central nutrient cycle metabolism(including carbon sugar transformation,denitrification,P mineralization and extracelluar sulfate transfer,etc.).Our result implies that human regulation of virus communities may be more important than bacterial communities in regulating and managing polluted water quality and nutrition.
文摘Tropical coastal ecosystems,vital habitats for economically significant marine species,face increasing threats from eutrophication driven by human-induced nutrient pollution.This study investigated the metabolomic profile of Anadara granosa,a marine bivalve,to identify metabolites indicative of eutrophic conditions.Conducted in Cirebon Bay,Indonesia,the research spanned five locations reflecting varying eutrophication levels.Bottom-layer water samples were analyzed for pH,dissolved oxygen,salinity,water transparency,and nutrient concentrations(phosphate,nitrate,ammonia).Proton-Nuclear Magnetic Resonance(Proton-NMR)metabolomics of A.granosa revealed metabolite variations linked to water quality.Eutrophic conditions,prevalent in the bay’s northern side,were characterized by inorganic nitrogen levels above 0.2 mg L^(-1) and phosphate exceeding 0.024 mg L^(-1).These were linked to urban,aquaculture,and agricultural runoff,driving increased phytoplankton biomass and reduced salinity variability.Metabolomic analysis identified inosine and dimethylglycine as potential biomarkers.Elevated inosine levels in eutrophic environments suggest increased cellular activity due to greater food availability,while higher dimethylglycine concentrations detected in low-nutrient as its role in osmotic regulation.Both metabolites correlated with ammonia concentrations(P<0.05,R^(2)=0.631),a key contributor to eutrophication.These findings highlight inosine and dimethylglycine as effective indicators of nutrient enrichment,providing insights into eutrophication’s impact on coastal ecosystems and A.granosa’s physiological responses.
基金supported by the National Natural Science Foundation of China(No.U2040210).
文摘Interaction between the Yangtze River and its tributaries in the Three Gorges Reservoir has an important influence on tributary algal blooms.Taking the Xiaojiang River as a typical tributary,a binary mixing model used stable isotopes of hydrogen and oxygen to quantitatively analyze the water contribution and nutrient source structure of the tributary backwater area.Results showed that the isotope content(δD:−54.7‰,δ^(18)O−7.8‰)in the Yangtze River was higher than that in the tributaries(δD:−74.2‰,δ^(18)O−17.0‰)in the non-flood season and lower than that in the tributaries in the flood season.The Yangtze River contributed more than 50%water volume of the tributary backwater area in the non-flood season.The total nitrogen and total phosphorus concentrations in the backwater area were estimated based on water contribution ratio,and the results were in good agreement with the monitoring results.Load estimation showed that the nitrogen and phosphorus contribution ratio of the Yangtze River to the tributary backwater area was approximately 40%-80%in the non-flood season,and approximately 20%-40%in the flood season,on average.This study showed that the interaction between the Xiaojiang River and the Yangtze River is significant,and that Yangtze River recharge is an important source of nutrients in the Xiaojiang backwater area,which may play a driving role in Xiaojiang River algal blooms.
基金The National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”under contract Nos IRASCC 01-01-02 and IRASCC 02-02the National Key Research and Development Program of China under contract No.2022YFE0136500+1 种基金the National Natural Science Foundation of China(NSFC)under contract Nos 41976228,42276255 and 42176227the Scientific Research Fund of the Second Institute of Oceanography under contract Nos JG2011,JG2211 and JG2013.
文摘Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is still unclear,partly due to lack of data spanning the entire summer.In this study,nitrate,phosphate,and silicate combined with temperature,salinity,and apparent oxygen utilization(AOU)were analyzed along 45°E in the Cosmonaut Sea during December 2019,January 2021,and February 2022.The variations in nutrient utilization in the euphotic layer were studied using biogeochemical tracers,and seasonal nutrient depletion was also estimated.The results showed that nutrient distribution varied significantly from December to February.Significant positive correlations were observed for nitrate and silicate concentrations with salinity and AOU,indicating that nutrient distributions were mainly influenced by water mass and phytoplankton production.Increasing∆[N*]and decreasing∆[Si*]in the upper 50 m were observed south of 63.5°S from December to February,which possibly contributed to a progressive shift in dominant phytoplankton population from Phaeocystis antarctica to diatoms.The seasonal nutrient depletion generally increased from December to February.Moreover,the consumption of silicate substantially increased compared to nitrate,indicating that the abundance of diatoms was increasing with time during the austral summer.Our observations suggest that nutrient utilization status is closely related to phytoplankton community structure in the euphotic layer of the Cosmonaut Sea.
基金Supported by the Ministry of Science and Technology of China,No.2022YFF1203300National Key Research and Development Program,No.2023YFC2307001China Postdoctoral Science Foundation,No.2023TQ0125 and No.2024M751031.
文摘Diet and nutrition significantly influence health, largely by regulating intestinalnutrient absorption. The intestinal epithelium, as the primary site for nutrientuptake, undergoes continuous renewal driven by precise regulation of intestinalstem cells (ISCs). Nutrient sensing and metabolism are key determinants of ISCfate, making ISCs a central link between nutrient metabolism and the regulationof intestinal tissue renewal and homeostasis. Understanding how ISCs respond ormake adaptations to nutritional signals is therefore vital for maintaining intestinalhomeostasis. Recent studies have spotlighted the origin and identity of ISCs andbroadened our insight into the plasticity and function of ISCs under differentconditions. Mitochondria, the central hubs of energy production and metabolicsignals provided by dietary components and metabolic substrates, such as glucose,amino acids, and lipids, govern the intricate balance between self-renewal anddifferentiation of ISCs. This review highlights the importance of nutrient sensing,metabolic regulation, and mitochondrial function in the specification of ISC fate.A thorough understanding of these mechanisms paves the way for the developmentof stem cell-based therapy for the mucosal healing of gastrointestinaldiseases and diet intervention to foster body health.
基金financial support of Guangdong Basic and Applied Basic Research Foundation(No.2022B1515020095)National Natural Science Foundation of China(No.52073140)。
文摘Deprivation of glucose and lactate provides an effective pathway to terminate the nutrients supplement for tumor growth.In this work,biomimetic nanozymes called m@BGLC are constructed for catalytic tumor inhibition through nutrients deprivation and oxidative damage induction.Concretely,the catalytic enzymes of glucose oxidase(GOx),lactate oxidase(LOx)and chloroperoxidase(CPO)are precrosslinked with bovine serum albumin(BSA)to construct nanozymes,which are then biomimetic functionalized with cancer cell membrane to prepare m@BGLC.Benefiting from the biomimetic camouflage with homologous cell membrane,m@BGLC inherit homotypic binding and immune escape abilities,facilitating the tumor targeting accumulation and preferable cell internalization for improved drug delivery efficiency.Subsequently,under the cascade catalysis of nanozymes,m@BGLC consume glucose and lactate for tumor starvation therapy through nutrients deprivation,and meanwhile,the resulting hyprochloric acid(HClO)causes an oxidative damage of cells to synergistically inhibit tumor growth.In vitro and in vivo findings demonstrate a robust tumor eradication effect of m@BGLC without obvious adverse reactions via the targeted combination therapy.Such cascade catalytic nanomedicine may inspire the development of sophisticated strategies for tumor combination therapy under unfavorable tumor microenvironments.
文摘Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the publisher's production process.The published incorrect version and the corrected version of Fig.4 are given below.
基金funded by the Kenya National Research Fund(NRF-Kenya,2018).
文摘The study determined the carbon stocks and litter nutrient concentration in tropical forests along the ecological gradient in Kenya.This could help understand the potential of mitigating climate change using tropical forest ecosystems in different ecological zones,which are being affected by climate change to a level that they are becoming carbon sources instead of sinks.Stratified sampling technique was used to categorize tropical forests into rain,moist deciduous and dry zone forests depending on the average annual rainfall received.Simple random sampling technique was used to select three tropical forests in each category.Modified consistent sampling technique was used to develop 10 main 20 m×100 m plots in each forest,with 202 m×50 m sub-plots in each plot.Systematic random sampling technique was used in selecting 10 sub-plots from each main plot for inventory study.Non-destructive approach based on allometric equations using trees’diameter at breast height(DBH),total height and species’wood specific gravity were used in estimating tree carbon stock in each forest.Soil organic carbon(SOC)and litter nutrient concentration(total phosphorus and nitrogen)were determined in each forest based on standard laboratory procedures.The results indicated that,whilst trees in rain forests recorded a significantly higher(p<0.001)DBH(20.36 cm)and total tree height(12.1 m),trees in dry zone forests recorded a significantly higher(p<0.001)specific gravity(0.67 kg m^(−3)).Dry zone tropical forests stored a significantly lower amount of total tree carbon of 73 Mg ha^(−1),compared to tropical rain forests(439.5 Mg ha^(−1))and moist deciduous tropical forests(449 Mg ha^(−1)).The SOC content was significantly higher in tropical rainforests(3.9%),compared to soils from moist deciduous(2.9%)and dry zone forests(1.8%).While litter from tropical rain forests recorded a significantly higher amount of total nitrogen(3.4%),litter from dry zone forests recorded a significantly higher concentration of total phosphorus(0.27%).In conclusion,ecological gradient that is dictated by the prevailing temperatures and precipitation affects the tropical forests carbon stock potential and litter nutrient concentration.This implies that,the changing climate is having a serious implication on the ecosystem services such as carbon stock and nutrients cycling in tropical forests.
基金supported by the National Natural Science Foundation of China(No.41977387)the National Research Foundation,Prime Minister’s Office,Singapore under its Campus for Research Excellence and Technological Enterprise(CREATE)program.
文摘Cyanobacterial blooms,exacerbated by climate change and eutrophication,increasingly compromise water quality by producing taste and odor(T&O)compounds including 2-methylisoborneol(MIB).Cyanobacteria synthesize MIB by redirecting carbon metabolism intermediates into the methylerythritol phosphate pathway.This process appears to be influenced by rising atmospheric CO_(2) partial pressure(pCO_(2)).This study examines how elevated pCO_(2) affects MIB production in Synechococcus sp.FACHB-1061 under varying nutrient conditions.The results indicate that elevated pCO_(2) boosts cyanobacterial biomass and total MIB yield,particularly in nutrient-rich environments,by reducing limitations in bioavailable inorganic carbon.In contrast,in nutrient-limited conditions,both total MIB concentration and per-cell production significantly increased with higher pCO_(2).Elevated pCO_(2) altered the activities of nitrate reductase and carbonic anhydrase,reducing impaired nitrogen assimilation and enhanced carbon fixation.The increase and compositional changes in extracellular polymeric substances suggested carbon overflow and a decline in cellular quality under insufficient nutrients.Additionally,markers of oxidative stress,such as increased superoxide dismutase activity and higher malondialdehyde levels,suggested that oxidative stress might stimulate secondary metabolite production.Metabolomic analysis revealed that critical intermediates of the Calvin cycle and glycolysis,such as glyceraldehyde-3-phosphate and acetyl-CoA,were upregulated with elevated pCO_(2) in nutrient-limited status,leading to increase of key precursors for MIB.These results highlight the complex interplay between nutrient and rising pCO_(2) in regulating cyanobacterial MIB biosynthesis.The findings suggest that conventional nutrient control strategies for mitigating cyanobacterial blooms and associated T&O issues may need reassessment under future climate scenarios.
基金funded by the Key Research and Development Project of Xinjiang Uygur Autonomous Region(2023A02002-2)the National Key Research and Development Program of China(2023YFD1901503)the Central Guidance Fund for Local Science and Technology Development of Xinjiang Uygur Autonomous Region(ZYYD2024CG03)。
文摘Biochar and animal manure application can improve crop yields in salt-affected soil.Previous studies have primarily applied biochar and animal manure either alone or at fixed ratios,while their combined effects with varying combination proportions are still unclear.To address this knowledge gap,we performed a 2-a experiment(2023-2024)in a salinized cotton field in Wensu County of Xinjiang Uygur Autonomous Region of China with the following 6 treatments:control;application of biochar(10t/hm^(2))alone(BC100%);application of cow manure(10 t/hm^(2))alone(CM100%);application of 70%biochar(7 t/hm^(2))combined with 30%cow manure(3 t/hm^(2))(BC70%+CM30%);application of 50%biochar(5 t/hm^(2))combined with 50%cow manure(5 t/hm^(2))(BC50%+CM50%);and application of 30%biochar(3 t/hm^(2))combined with 70%cow manure(7 t/hm^(2))(BC30%+CM70%).By measuring soil pH,electrical conductivity,soil organic matter,available phosphorus,available potassium,and available nitrogen at 0-20 and 20-40 cm depths,as well as yield components and cotton yield in 2023 and 2024,this study revealed that soil nutrients in the 0-20 cm depth were more sensitive to the treatment.Among all the treatments,BC50%+CM50%treatment had the highest value of soil pH(9.63±0.07)but the lowest values of electrical conductivity(161.9±31.8μS/cm),soil organic matter(1.88±0.27 g/kg),and available potassium(42.72±8.25 mg/kg)in 2024.Moreover,the highest cotton yield(5336.63±467.72 kg/hm^(2))was also observed under BC50%+CM50%treatment in 2024,which was 1.9 times greater than that under the control treatment.In addition,cotton yield in 2023 was jointly determined by yield components(density and number of cotton bolls)and soil nutrients(available phosphorus and available potassium),but in 2024,cotton yield was only positively related to yield components(density,number of cotton bolls,and single boll weight).Overall,this study highlighted that in salt-affected soil,the combination of biochar and cow manure at a 1:1 ratio is recommended for increasing cotton yield and reducing soil salinity stress.
基金The Major Science and Technology Plan of Hainan Province under contract No.ZDKJ2021008the Hainan Provincial Natural Science Foundation of China under contract No.623RC456+1 种基金the Hainan Province Science and Technology Special Fund under contract Nos ZDYF2021SHFZ064 and ZDYF2022SHFZ056the Collaborative Innovation Center of Marine Science and Technology in Hainan University under contract No.XTCX2022HYC19.
文摘The exchange of inorganic nutrients at the coastal sediment-water interface(SWI)plays a crucial role in regulating the nutrient budget in overlying water.The related studies mainly focus on the mid-to high-latitude regions,leaving a significant gap in the quantitative assessment of nutrient exchange and environmental controls at the SWI in lowlatitude coastal regions.We quantitatively assess the exchange of inorganic nutrients at the SWI in three tropical bays(Dongzhai Harbor,Xiaohai Lagoon,Qinglan Harbor).Sediments act as a source of ammonium,phosphate,and silicate,but for nitrate,sediments can be both a source and sink,although with substantial spatial and temporal variations in their fluxes.Labile organic matter is a critical regulator for the fluxes of inorganic nutrients at the SWI.The sedimentary nutrients input with high N/P molar ratio will alter the nutrient stoichiometry to mitigate the nitrogen limitation in coastal waters.However,the internal sediment release in these tropical bays plays a relative weak role in contributing to the nutrient addition in comparison with the other external nutrient sources including riverine input,submarine groundwater discharge,and atmospheric deposition.According to the global compilation on SWI nutrient fluxes,we propose that water column primary production and external inputs to interpret the variation in exchange and fluxes of nutrients at the SWI in different ecosystems.Such a conceptual understanding of these chain biogeochemical processes involving external nutrient input,primary production,particulate organic matter settling,and the accumulation and release of inorganic nutrients in sediments will be helpful for the scientific-based pollution prevent and control in coastal waters.
