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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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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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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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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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Effects of Forest Types on Soil Available Nutrients and Carbon Contents in Coastal Areas,China
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作者 Zirui Chen Jiale Liu Haijun Sun 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第10期2557-2569,共13页
Clarifying the soil nutrient dynamics caused by forest type variations in the coastal region helps scientifically to apply fertilizer to forest plantations and enhance the carbon(C)sink capacity.Pure forests of Ligust... Clarifying the soil nutrient dynamics caused by forest type variations in the coastal region helps scientifically to apply fertilizer to forest plantations and enhance the carbon(C)sink capacity.Pure forests of Ligustrum and Metasequoia,as well as their mixed forests,in a coastal region of China were investigated by collecting 0-20 and 20-40 cm soil samples and analyzing their differences in bulk density,water content,pH,soil organic matter(SOM),ammonium(NH_(4)^(+)-N),nitrate(NO_(3)^(-)-N)and total nitrogen(TN),available phosphorus(AP)and potassium(AK),microbial biomass C(MBC)and N(MBN),and enzyme activity.The results demonstrated that different forest types had no significant(p≥0.05)effect on 0-20 cm soil bulk density,water content,pH,NH_(4)^(+)-N,and SOM.However,the surface soil NO_(3)^(-)-N,TN,AP,and AK contents as well as enzyme activity changed significantly(p<0.05),in which the soil AK content of the ligustrum×metasequoia mixed forest was 47.5%and 65.5%higher than that of the ligustrum and metasequoia pure forest,respectively.The mixed forest soil had the highest MBN content,which was significantly(p<0.05)25.1%higher than that in the pure metasequoia forest.Meanwhile,soil phosphatase activities in ligustrum and metasequoia pure forests were significantly(p<0.05)lower than those in the mixed forests by 17.4%and 43.1%,respectively.However,soil NO_(3)^(-)-N and AP contents in the metasequoia pure forest were significantly(p<0.05)higher than those in the ligustrum pure forest and mixed forests.Soil MBC content and reductase NO_(3)^(-)-N activity were significantly(p<0.05)higher in ligustrum pure forest than in metasequoia pure forest and mixed forests.In addition,the results of two-way ANOVA showed that there were no significant(p≥0.05)differences in nutrient contents(e.g.,NH_(4)^(+)-N,AP,AK,and SOM)in different soil layers(0-20 and 20-40 cm)within the same forest type,except for NO_(3)^(-)-N.However,forest types had a significant(p<0.05)impact on NO_(3)^(-)-N and AP contents in 20-40 cm soil layer.Combining the two factors of forest stand and soil layer,there was a significant(p<0.05)interaction effect for their soil NH_(4)^(+)-N,NO_(3)^(-)-N,AP,and AK contents.In conclusion,significant(p<0.05)differences were observed in nutrient contents in 0-20 cm soil layer from different forest types,with soil fertility indices inmixed forests generally higher than in pure forests.Therefore,establishing mixed forests in coastal saline region is recommended to retain soil fertility and to enhance the C sink capacity of forestry. 展开更多
关键词 Agroforestry ecosystem mixed forest NITROGEN saline-alkali land soil nutrient SOM
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The link between dietary nutrients intake and cardiovascular diseases in cold regions
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作者 Rennan Feng Qianqi Hong +5 位作者 Jingjing Cao Jian Li Lanxin Deng Jing Wang Yang Zhao Cheng Wang 《Frigid Zone Medicine》 2024年第1期1-11,共11页
Background:The cold winter weather in northern China influences the dietary habits of its residents,contributing to a heightened risk of cardiovascular disorders,such as hypertension and coronary heart disease.Key fac... Background:The cold winter weather in northern China influences the dietary habits of its residents,contributing to a heightened risk of cardiovascular disorders,such as hypertension and coronary heart disease.Key factors include low vegetable consumption and high salt and fat intakes.This study aims to investigate the relationships between northern dietary nutrient intake in northern China and cardiovascular disorders during the winter season.Methods:A food frequency questionnaire tailored to the actual eating habits in northern China was designed.Retrospective data from 955 Chinese adults were collected from November to March between 2014 to 2023.Logistic regression was employed to analyze the relationship between dietary nutrients and cardiovascular diseases,with model performance assessed using receiver operating characteristic(ROC)curves.Results:Adjusted for gender,age,and body mass index(BMI),an inverse association was observed between vitamin A(OR=0.706,95%CI:0.550,0.907),nicotinic acid(OR=0.584,95%CI:0.447,0.762),phosphorus(OR=0.777,95%CI:0.608,0.994),selenium(OR=0.719,95%CI:0.560,0.923),zinc(OR=0.683,95%CI:0.531,0.880),methionine(OR=0.730,95%CI:0.569,0.936),arginine(OR=0.753,95%CI:0.588,0.964),lysine(OR=0.706,95%CI:0.550,0.907),aspartic acid(OR=0.730,95%CI:0.569,0.936)and hypertension.Additionally,a negative association was found between niacin(OR=0.752,95%CI:0.597,0.946)and coronary heart disease.Conversely,a positive association was identified between iodine and hypertension(OR=1.305,95%CI:1.020,1.669)and coronary heart disease(OR=1.301,95%CI:1.037,1.634).Conclusion:Our study suggests that maintaining a balanced dietary intake of vitamin A,niacin,phosphorus,selenium,zinc,methionine,arginine,lysine,and aspartic acid can be beneficial in preventing hypertension.Adequate niacin intake is associated with a lower risk of coronary heart disease.However,excessive iodine intake may contribute to hypertension and coronary heart disease. 展开更多
关键词 nutrients NORTHERN HYPERTENSION coronary heart disease COLD
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Temporal, Spatial, and Hypsometrical Dispersion of Nutrients in the Hula Valley, Israel
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作者 Moshe Gophen Valerie Orlov-Levin 《Open Journal of Ecology》 2024年第8期604-628,共25页
Until 1957 most of the Hula Valley was occupied by swampy wetland covered by dense vegetation and old Lake Hula. Organic matter was accumulated in the bottom, decomposed under anoxic conditions creating Peat material.... Until 1957 most of the Hula Valley was occupied by swampy wetland covered by dense vegetation and old Lake Hula. Organic matter was accumulated in the bottom, decomposed under anoxic conditions creating Peat material. The wetland and the old lake were drained and the land-use was converted into agricultural development. Nutrients migrations from the Hula Valley through the headwater discharges carrying nutrients, where nitrogen enhancement is critical, significantly affecting water quality in down-stream Lake Kinneret. The fate of the Hula originated nutrients is partly known whilst fate of the others which might be probably a threat on the Kinneret water quality is unknown. The hypsometrical and spatial distribution of the Hula Valley originated nutrients within three depths level was indicated: shallowest level of surface water, intermediate level of underground water table and the deepest level of Lignite waters. The Hypsometrical and spatial distribution and regional origin of the nutrient in the Hula Valley was defined. Organic Nitrogen, Sulfate and Nitrates are mostly Hula Valley originated nutrients whilst most of the Phosphorus externally contributed to Lake Kinneret originate outside the Hula Valley. An underground north-south Hydrological gradient and nutrient migration along was indicated. It is suggested that an underground plastic barrier do not totally prevent horizontal nutrient migration. Hypsometrical downward migrated nutrients probably accumulate within the “Lignite” depth level. Management policy of increasing Peat Soil moisture, is recommended. 展开更多
关键词 Hula Valley Kinneret nutrients RUNOFF UNDERGROUND LIGNITE
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Effect of Saline Water on Soil Acidity, Alkalinity and Nutrients Leaching in Sandy Loamy Soil in Rwamagana Bella Flower Farm, Rwanda
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作者 Abel Mwubahaman Wali Umaru Garba +3 位作者 Hussein Bizimana Jean de Dieu Bazimenyera Eric Derrick Bugenimana Jean Nepomuscene Nsengiyumva 《Agricultural Sciences》 2024年第1期15-35,共21页
The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific consideration... The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels. 展开更多
关键词 nutrients LEACHING Saline Water Soil Acidity Soil Alkalinity
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Relationships between Application Amount of Quicklime and Soil Nutrients,Flue-cured Tobacco Quality in Panzhihua City 被引量:2
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作者 潘兴兵 张宗锦 +2 位作者 庞良玉 官宇 汪莹 《Agricultural Science & Technology》 CAS 2015年第12期2707-2710,共4页
[Objective] This study aimed to investigate the improving effect of quick- lime on acid soil in tobacco-growing areas in Panzhihua City. [Method] The effects of four application amounts (450, 900, 1 350 and 1 800 kg/... [Objective] This study aimed to investigate the improving effect of quick- lime on acid soil in tobacco-growing areas in Panzhihua City. [Method] The effects of four application amounts (450, 900, 1 350 and 1 800 kg/hm2) of quicklime on soil nutrients and flue-cured tobacco quality were observed for two consecutive years. [Result] In acid soil, the application of quicklime significantly improved soil pH. In addition, it showed significant effects on soil nutrients, flue-cured tobacco quality, tobacco output and tobacco leaf chemical components. When the application amount of quicklime was increased to 1 350 kg/hm2, the improving effect of quick- lime on soil nutrients was best, the flue-cured tobacco yield and quality all reached the highest, and the chemical components of tobacco leaves were closest to the in- herent indicators of high-quality tobacco leaves. [Conclusion] This study will provide certain reference for accurate application of quicklime in tobacco-growing area in Panzhihua City. 展开更多
关键词 Panzhihua QUICKLIME Soil nutrients Flue-cured tobacco QUALITY
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Monthly variation in litterfall and the amount of nutrients in an Aleurites montana plantation 被引量:11
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作者 LIN Han HONG Tao WU Cheng-zhen CHEN Hui CHEN Can LI Jian LIN Yong-ming FAN Hai-lan 《Forestry Studies in China》 CAS 2012年第1期30-35,共6页
In this study, the dynamics of monthly variation in litterfall and the amount of nutrients, i.e., organic C, N, P and K, in an Aleurites montana plantation were analyzed, based on a field study and experiments over on... In this study, the dynamics of monthly variation in litterfall and the amount of nutrients, i.e., organic C, N, P and K, in an Aleurites montana plantation were analyzed, based on a field study and experiments over one year. The results show that the litterfall mass of A. montana collected generally presents an ascending trend with maximum defoliation occurring in the autumn and winter (October-December), accounting for 75.67% of the total amount of annual litterfalk The sequence in the amount of nutrients in A. montana litter was as follows: organic C 〉 N 〉 K 〉 P; their monthly amounts show various dynamic curves. Similar to the dynamics of the mass of monthly litterfall, the monthly returns of C, N, P and K generally show an ascending trend with their peak values all occurring in December. The mass of A. montana litterfall and the dynamics of its monthly nutrient return provide, to a certain degree, a scientific reference for planting and fertilizing A. montana. 展开更多
关键词 Aleurites montana LITTERFALL monthly variation nutrient amounts
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Analysis of differences in nutrients chemistry in seamount seawaters in the Kocebu and M4 seamounts in Western Pacific Ocean 被引量:1
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作者 Jun MA Jinming SONG +4 位作者 Xuegang LI Qidong WANG Huamao YUAN Ning LI Liqin DUAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第5期1662-1674,共13页
Comprehensive surveys were conducted in the Kocebu deep seamount and the M4 shallow seamount in the Western Pacific Ocean in March 2018 and May 2019,respectively.The distributions of nutrients in euphotic zone of the ... Comprehensive surveys were conducted in the Kocebu deep seamount and the M4 shallow seamount in the Western Pacific Ocean in March 2018 and May 2019,respectively.The distributions of nutrients in euphotic zone of the two seamount-areas were revealed,and the causative controlling factors were analyzed.Results show that the vertical distribution of nutrients in the two seamount-areas accorded with the general law of the oligotrophic ocean.The concentrations of NO_(3)-N,PO_(4)-P,and SiO_(3)-Si generally increased gradually with the increase of water depth,and they were extremely low in water layers within100 m.The area of high NO_(2)-N concentration well agreed with the Deep Chlorophyll Maximum Layer.On the other hand,the distribution of water masses and phytoplankton and hydrological conditions in the two seamount-areas were different,resulting in lower concentrations of NO_(3)-N,PO_(4)-P,and SiO_(3)-Si in the water layers below 100 m in the Kocebu seamount area than those in the M4 seamount area.In addition,NO_(2)-N was affected by the distribution of phytoplankton,and distributed mainly in the water layers of 150 and100 m.There was upwelling in the euphotic zone of M4 seamount area,causing accumulations of nutrients and phytoplankton around the seamount,forming a"seamount effect";however,no such an effect was found in Kocebu seamount area.Affected by the composition of biological community and the"seamount effect",the nitrogen limitation in the M4 seamount area was not significant,and the dissolved inorganic nitrogen(DIN):PO_(4)-P and SiO_(3)-Si:DIN were closer to the Redfield ratios. 展开更多
关键词 nutrients comparison SEamount Western Pacific Ocean
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Influence of methyl donor nutrients as epigenetic regulators in colorectal cancer:A systematic review of observational studies 被引量:2
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作者 Lourdes Pilar Chávez-Hidalgo Silvia Martín-Fernández-de-Labastida +1 位作者 Marian M de Pancorbo Marta Arroyo-Izaga 《World Journal of Gastroenterology》 SCIE CAS 2023年第7期1219-1234,共16页
BACKGROUND Dietary methyl donors might influence DNA methylation during carcinogenesis of colorectal cancer(CRC).However,whether the influence of methyl donor intake is modified by polymorphisms in such epigenetic reg... BACKGROUND Dietary methyl donors might influence DNA methylation during carcinogenesis of colorectal cancer(CRC).However,whether the influence of methyl donor intake is modified by polymorphisms in such epigenetic regulators is still unclear.AIM To improve the current understanding of the molecular basis of CRC.METHODS A literature search in the Medline database,Reference Citation Analysis(https://www.referencecitationanalysis.com/),and manual reference screening were performed to identify observational studies published from inception to May 2022.RESULTS A total of fourteen case-control studies and five cohort studies were identified.These studies included information on dietary methyl donors,dietary components that potentially modulate the bioavailability of methyl groups,genetic variants of methyl metabolizing enzymes,and/or markers of CpG island methylator phenotype and/or microsatellite instability,and their possible interactions on CRC risk.CONCLUSION Several studies have suggested interactions between methylenetetrahydrofolate reductase polymorphisms,methyl donor nutrients(such as folate)and alcohol on CRC risk.Moreover,vitamin B6,niacin,and alcohol may affect CRC risk through not only genetic but also epigenetic regulation.Identification of specific mechanisms in these interactions associated with CRC may assist in developing targeted prevention strategies for individuals at the highest risk of developing CRC. 展开更多
关键词 Colorectal cancer DNA methylation EPIGENETICS Methyl donors Microsatellite instability nutrients
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Coral reef ecological pump for gathering and retaining nutrients and exporting carbon:a review and perspectives 被引量:1
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作者 Linbin Zhou Yehui Tan Liangmin Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第6期1-15,共15页
How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oas... How coral reefs with high productivity and biodiversity can flourish in oligotrophic tropical oceans has inspired substantial research on coral reef ecosystems.Increasing evidence shows that similar to water in an oasis in the desert,there are stable nutrient supplies to coral reefs in oligotrophic oceans.Here,with emphasis on the fluxes of organic matter,we summarize at the ecosystem level(1)the multiple input pathways of external nutrients,(2)the storage of nutrients in reef organisms,(3)the efficient retaining and recycling of dissolved and particulate organic matter within coral reef ecosystems,(4)the distinctly high phytoplankton productivity and biomass inside and near oceanic coral reefs,and(5)the export of reef-related organic carbon to adjacent open oceans.These properties enable coral reefs to function as ecological“pumps”for gathering nutrients across ecosystems and space,retaining and recycling nutrients within the ecosystem,supporting high phytoplankton productivity,and exporting organic carbon to adjacent open oceans.Particularly,the high phytoplankton productivity and biomass make waters around coral reefs potential hotspots of carbon export to ocean depths via the biological pump.We demonstrate that organic carbon influx is vital for coral reef ecosystems’carbon budget and carbon export.The concept of the coral reef ecological pump provides a framework to improve the understanding of the functioning of the coral reef ecosystem and its responses to disturbance.Prospects of the coral reef ecological pump in coral reef studies are discussed in changing oceans driven by human activities and global change in the Anthropocene. 展开更多
关键词 Darwin’s Paradox coral reef nutrients coral reef ecological pump carbon export ocean carbon cycle
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Spatial distribution and export of nutrients and metal elements in the subterranean estuary of Daya Bay
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作者 Zhaoxi Liu Mingchen Ge +4 位作者 Qianqian Wang Xuejing Wang Kai Xiao Gang Li Hailong Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期77-86,共10页
Subterranean estuaries(STE)are important seawater-groundwater mixing zones with complex biogeochemical processes,which play a vital role in the migration and transformation of dissolved materials.In this study,we firs... Subterranean estuaries(STE)are important seawater-groundwater mixing zones with complex biogeochemical processes,which play a vital role in the migration and transformation of dissolved materials.In this study,we first investigated the spatial distributions of dissolved inorganic nitrogen(DIN),dissolved inorganic phosphorous(DIP),dissolved inorganic silicon(DSi)and metal elements(As,Ba,Cr,Cu,Fe,Mn,Ni,Pb,and Zn)in STE including upper intertidal,seepage face and subtidal zones.We then estimated submarine groundwater discharge(SGD)and associated nutrient and metal element fluxes.From the generalized Darcy’s law method,SGD was estimated to be 30.13 cm/d,which was about 7 times larger than the inflow(4.16 cm/d).The nutrient and metal fluxes from SGD were estimated to be(5.33±4.99)mmol/(m^(2)·d)for DIN,(0.22±0.03)mmol/(m^(2)·d)for DIP,(16.20±2.05)mmol/(m^(2)·d)for DSi,(1325.06±99.10)μmol/(m^(2)·d)for Fe,(143.41±25.13)μmol/(m^(2)·d)for Mn,(304.06±81.07)μmol/(m^(2)·d)for Zn,(140.21±13.33)μmol/(m^(2)·d)for Cu,(84.49±2.94)μmol/(m^(2)·d)for Pb,(37.38±5.51)μmol/(m^(2)·d)for Ba,(27.88±3.89)μmol/(m^(2)·d)for Cr,(10.10±6.33)μmol/(m^(2)·d)for Ni,and(6.25±3.45)μmol/(m^(2)·d)for As.The nutrient and metal fluxes from SGD were relatively higher than those from the inflow,suggesting that nearshore groundwater acted as the sources of nutrients and metal elements discharging into the sea.The environmental potential pollution of coastal seawater was evaluated by pollution factor index(Pi),comprehensive water quality index(CWQI),and ecological risk index(ERI).Pb mainly caused potential danger of nearshore environment with considerable contamination(Pi=5.78±0.19),heavy pollution(CWQI=4.09)and high ecological risk(ERI=18.00).This study contributed to better understanding the behavior of nutrients and metal elements and improving the sustainable management of STE under the pressure of anthropogenic activities and climate change. 展开更多
关键词 subterranean estuaries submarine groundwater discharge nutrients metal elements pollution assessment Daya Bay
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Effect of light and nutrients on interspecific interactions between submerged macrophytes:implications for restoration of multispecies aquatic vegetation in eutrophic lakes
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作者 Yiping WANG Xiaoguang XU +5 位作者 Dujun LI Yongjun LU Xinhou ZHANG Chuyao YANG Qiu JIN Guoxiang WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1821-1833,共13页
Constructing multispecies submerged vegetation systems and maintaining stable seasonal succession is crucial for restoring shallow eutrophic lakes.However,little is known about the interactions between successional an... Constructing multispecies submerged vegetation systems and maintaining stable seasonal succession is crucial for restoring shallow eutrophic lakes.However,little is known about the interactions between successional and existing species of different growth forms,particularly under the low light and high nutrient conditions of eutrophic lakes.We measured the functional traits of mature Vallisneria natans(Lour.)Hara plants and Potamogeton crispus L.shoots in monoculture and mosaic patterns under different light and nutrient conditions.The effect of light on functional traits of the submerged macrophyte species was more significant than that of nutrients,but the reverse was true for P.crispus biomass allocation.Moreover,interspecific interactions affected only the submerged macrophytes under the low light condition and varied with species.Specifically,the interaction of P.crispus to V.natans was biased towards competition,while the interaction of V.natans to P.crispus was converted from facilitation to competition by eutrophication,particularly in the homogenous mosaic growth pattern.This study demonstrates that sufficient light is a prerequisite and patch planting is an effective means to form a multispecies submerged vegetation system.In addition,we emphasize that the coexistence of eutrophication and low light will likely result in a competition between submerged macrophytes thus simplifying the vegetation,even if their growth forms and growing seasons are different.These findings help explain the collapse of multispecies submerged vegetation and guide the restoration of aquatic plants in eutrophic lakes. 展开更多
关键词 submerged macrophyte LIGHT NUTRIENT MONOCULTURE MOSAIC interspecific interaction
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Association of nutrients intake during pregnancy with the risk of allergic disease in offspring:a meta-analysis of prospective cohort studies
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作者 Hua Feng Yan Chen +5 位作者 Xiujuan Xiong Qunying Xu Zhongwei Zhang Qinghua Xi Yongning Wu Yuanan Lu 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期711-719,共9页
To investigate the role of nutrients intake during pregnancy with longitudinal development of rhinitis,asthma,eczema,wheeze,and food allergy in offspring.The PubMed,Embase,and Cochrane library were searched for articl... To investigate the role of nutrients intake during pregnancy with longitudinal development of rhinitis,asthma,eczema,wheeze,and food allergy in offspring.The PubMed,Embase,and Cochrane library were searched for articles published throughout May 2022.The pooled effect estimate were presented using relative risk and calculated by the random-effects model.Twenty-three prospective cohort studies enrolling 210817 individuals were included.The risk of wheeze in offspring were lowered when high vitamin D,vitamin E,zinc,and milk intakes during pregnancy,whereas high meat intake during pregnancy could induce additional risk of wheeze in offspring.Moreover,highβ-carotene and magnesium intakes during pregnancy were related to lower eczema risk in offspring,whereas eczema risk in offspring was increased for pregnant women with high intake of butter and margarine.Finally,the asthma risk in offspring could protect against for pregnant women with high intake of vitamin D and apple,whereas high folic acid during pregnancy could produce excess asthma risk in offspring.This study provides the summary evidences regarding the role of nutrients intake during pregnancy and subsequent risk of rhinitis,asthma,eczema,wheeze,and food allergy,and further effective intervention strategies should be employed to improve childhood allergic diseases. 展开更多
关键词 nutrients PREGNANCY OFFSPRING ALLERGY Immune disease
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Research Progress on Nutrients of Artemisia argyi
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作者 Gao He-mei Li Hong-mei Jiang Cheng-zhe 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期89-96,共8页
Artemisia argyi is a traditional Chinese herb,which is widely distributed in various areas in China.In recent years,due to the development of A.argyi related industries and the continuous improvement of people’s heal... Artemisia argyi is a traditional Chinese herb,which is widely distributed in various areas in China.In recent years,due to the development of A.argyi related industries and the continuous improvement of people’s health awareness,experts and scholars are concerned about the nutrients and effects of A.argyi.A.argyi is rich in carbohydrates,proteins,essential amino acids,fatty acids,minerals,vitamins,dietary fibers,flavonoids and other nutrients.It has the effects of antioxidant,anti-tumor,antibacterial,antiinflammatory,neuroprotection and immune regulations,and has been widely applied in the fields of COVID-19 prevention,food health care,food preservation and feed breeding,and has good development potential.This review summarized the research and application of A.argyi nutrients,in order to provide reference and application for further study. 展开更多
关键词 Artemisia argyi nutrients APPLICATION
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Effects of Tillage Depth on Nutrients and Microbial Communities in Tobacco-Planting Soil
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作者 Guanxing Shang Qibo Zou +7 位作者 Jiamei Zhang Jing Wang Yuanbo Zhang Mingchang Liu Shihai Wang Dan Zhang Wei Wang Yiming Wang 《Agricultural Sciences》 2023年第12期1702-1715,共14页
The implementation of appropriate tillage practices is of great significance for agricultural production. However, the effects of different tillage depths on soil nutrients content and microbial communities in tobacco... The implementation of appropriate tillage practices is of great significance for agricultural production. However, the effects of different tillage depths on soil nutrients content and microbial communities in tobacco-planting soils are still lacking systematic research. In this study, three different tillage depths of 15 cm (T1), 20 cm (T2), and 30 cm (T3) were set up for field experiments in Liupanshui, Guizhou Province, to explore the effects of tillage depth on tobacco-planting soil nutrients and bacterial and fungal communities based on 16S rRNA and ITS sequencing and figure out the key factors affecting soil microbial communities. The results showed that T2 and T3 increased the contents of organic matter, total nitrogen, total phosphorus, available phosphorus, and available potassium in tobacco-planting soil, and increased the diversity of bacterial communities compared with T1. There was no significant difference in the structure of bacterial and fungal communities in different tillage depth treatments, but some dominant genera were significantly enriched in T2 and T3. Desulfobacter, Setophoma, Humicola, and Acremonium were significantly enriched in T2. Chthonomonas and Fusarium were significantly enriched in T3. These genera favor the decomposition of organic matter and the cycling of nutrients, and control soil pests and diseases. Redundancy analysis indicated that TP and AK were the key factors influencing the dominant genera of bacteria and fungi. This study provides a scientific basis for the selection of soil tillage depth for tobacco production in this region. 展开更多
关键词 Tillage Depth TOBACCO Soil nutrients Bacterial Community Fungal Community
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Latest advances in epigenetic mechanisms of nutrients in breast cancer and the relation of homocysteine mechanism
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作者 Rümeysa Rabia Kocatürk Vildan Enisoğlu Atalay 《Food and Health》 2023年第2期13-21,共9页
The incidence rate of breast cancer is the second highest of all cancers.Alterations to one's epigenome are among the most critical factors in breast cancer control.In breast cancer,nutrients can influence epigene... The incidence rate of breast cancer is the second highest of all cancers.Alterations to one's epigenome are among the most critical factors in breast cancer control.In breast cancer,nutrients can influence epigenetic pathways and homocysteine(Hcy)levels.Hcy has been related to cognitive decline,Alzheimer's disease,and cancer.Similar to how altered Hcy metabolism is strongly influenced by genetic,epigenetic,and environmental factors,it is significantly linked to cancer.This review aims to discuss the relationship between the levels of Hcy in breast cancer and the effects of nutrients on epigenetic processes.Dietary interventions have the ability to control epigenetic processes,and the Hcy levels are associated with both epigenetic mechanisms and nutritional supplements in breast cancer.Certain nutrients have been discovered to have an impact on these processes.Altered Hcy metabolism is influenced by genetic,epigenetic,and environmental factors and has a substantial link to the emergence of cancer.Nutrients,such as folic acid,vitamin B12 and many phytonutrients that have been found to affect the epigenetic processes in breast cancer may alter DNA methylation and histone modification,which in turn may affect how cancer cells behave.The review emphasizes the need for additional studies to fully comprehend nutrition's potential for the epigenetic mechanism and the relation between Hcy metabolism in breast cancer. 展开更多
关键词 breast cancer EPIGENETIC HOMOCYSTEINE NUTRITION nutrients
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Effect of root derived organic acids on the activation of nutrients in the rhizosphere soil 被引量:6
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作者 陈永亮 郭玉强 +3 位作者 韩士杰 邹春静 周玉梅 程国玲 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期115-118,164,共4页
Four types of soils, including brown coniferous forest soil, dark brown soil, black soil, and black calic soil, sampled from three different places in northeast China were used in this test. The functions of two root-... Four types of soils, including brown coniferous forest soil, dark brown soil, black soil, and black calic soil, sampled from three different places in northeast China were used in this test. The functions of two root-derived organic acids and water were simulated and compared in the activation of mineral nutrients from the rhizosphere soil. The results showed that the organic acids could activate the nutrients and the activated degree of the nutrient elements highly depended on the amount and types of the organic acid excreted and on the physiochemical and biochemical properties of the soil tested. The activation effect of the citric acid was obviously higher than that of malic acid in extracting Fe, Mn, Cu, and Zn for all the tested soil types. However, the activation efficiencies of P, K, Ca, and Mg extracting by the citric acid were not much higher, sometimes even lower, than those by malic acid. The solution concentration of all elements increased with increase of amount of the citric acid added. 展开更多
关键词 Organic acids NUTRIENT ACTIVATION RHIZOSPHERE
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