期刊文献+
共找到3,732篇文章
< 1 2 187 >
每页显示 20 50 100
Effects of Biostimulation-Bioaugmentation on Coastal Microbial Community in an in situ Mesocosm System
1
作者 YUAN Fangzheng ZHAO Yangyong +2 位作者 DAI Yulai YANG Wen ZHU Jinyong 《Journal of Ocean University of China》 CAS CSCD 2024年第1期233-246,共14页
Globally,various types of pollution affect coastal waters as a result of human activities.Bioaugmentation and biostimulation are effective methods for treating water pollution.However,few studies have explored the res... Globally,various types of pollution affect coastal waters as a result of human activities.Bioaugmentation and biostimulation are effective methods for treating water pollution.However,few studies have explored the response of coastal prokaryotic and eukaryotic communities to bioaugmentation and biostimulation.Here,a 28-day outdoor mesocosm experiment with two treatments(bioaugmentation-A and combined treatment of bioaugmentation and biostimulation-AS)and a control(untreated-C)were carried out.The experiment was conducted in Meishan Bay to explore the composition,dynamics,and co-occurrence patterns of prokaryotic and eukaryotic communities in response to the A and AS using 16S rRNA and 18S rRNA gene amplicon sequencing.After treatment,Gammaproteobacteria and Epsilonproteobacteria were significantly increased in group AS compared to group C,while Flavobacteriia and Saprospirae were significantly reduced.Dinoflagellata was significantly reduced in AS compared to C,while Chrysophyta was significantly reduced in both AS and A.Compared to C,the principal response curve analyses of the prokaryotic and eukaryotic communities both showed an increasing trend followed by a decreasing trend for AS.Furthermore,the trends of prokaryotic and eukaryotic communities in group A were similar to those in group AS compared with group C,but AS changed them more than A did.According to the species weight table on principal response curves,a significant increase was observed in beneficial bacteria in prokaryotic communities,such as Rhodobacterales and Oceanospirillales,along with a decrease in autotrophs in eukaryotic communities,such as Chrysophyta and Diatom.Topological properties of network analysis reveal that A and AS complicate the interactions between the prokaryotic and eukaryotic communities.Overall,these findings expand our understanding of the response pattern of the bioaugmentation and biostimulation on coastal prokaryotic and eukaryotic communities. 展开更多
关键词 prokaryotic community eukaryotic community BIOAUGMENTATION BIOSTIMULATION coastal waters
下载PDF
Community-led total sanitation(CLTS)implementation in West Mamprusi Municipal Assembly in Ghana.What do communities think eleven years on?
2
作者 Elijah Adam Emmanuel Badu 《Global Health Journal》 2024年第2期67-73,共7页
Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)stil... Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)still have no access to adequate toilet facilities.This has brought untold health repercussions to the inhabitants,the community,and the environment at large.To address this menace,the community-led total sanitation(CLTS)was implemented.This study aimed to assess communities’perspectives on the implementation of CLTS and to understand the factors influencing its success and failures.Methods A mixed-method approach involving sequential qualitative and quantitative methods was employed in this study.Participants for the quantitative study were randomly selected and surveyed using questionnaires.The qualitative study employed focus group discussion involving purposively sampled participants including assembly members,opinion leaders,and assembly staff.Results The CLTS program in WMMA realized an apparent use of construction and proper use of household latrines leading to a reduction of open defecation free(ODF)and two communities achieving sanitized status in the history of the study area,enabling the training of latrine artisans and natural leaders to facilitate the CLTS expansion and sustainability,improved sanitation and hygiene,strengthened the enforcement of community rules and regulations and many others.Conclusion The CLTS program has received more widespread acceptance in the study area than the previous government policy of constructing public toilets,which was greeted with massive failures due to poor implementation.To ensure that gains achieved through CLTS implementation are sustained longer,it is recommended that chiefs and opinion leaders should be involved in the CLTS programs to ensure checks and enforcement.The entrenchment of bylaws and more education to address enduring myths and misconceptions will sustain the program.Subsidies in the form of sanitation loans for latrine construction materials by the government and supporting non-governmental organizations(NGOs)will be paramount in sustaining ODF. 展开更多
关键词 community-led total sanitation(CLTS) community development Ghana SANITATION
下载PDF
Construction of Urban Mixed-age Community: Opportunities, Challenges and Countermeasures: A Case Study of“Fangjia Hutong”in Beijing
3
作者 FAN Anuo 《Journal of Landscape Research》 2024年第3期31-36,共6页
In the context of China’s economic development and population aging,the innovation and exploration of the old-age care model has emerged as a new community transformation and development direction.Given the differing... In the context of China’s economic development and population aging,the innovation and exploration of the old-age care model has emerged as a new community transformation and development direction.Given the differing needs and characteristics of individuals across the lifespan,it is evident that a design approach that incorporates mixed-age integration and mutual-help communities is a viable strategy for enhancing intergenerational exchanges.This entails the creation of a diverse and open community that is conducive to habitation for individuals of all ages,encompassing the full spectrum of needs,from those of young children to the elderly.Such a community must be designed and constructed with the population in mind,from the initial planning and design stages to the operational phase.This encompasses a comprehensive range of services,including food,clothing,housing,transportation,and medical care and recreation. 展开更多
关键词 Mixed-age community Old-age care community construction
下载PDF
Community Caregivers’ Experiences and Programmatic Strategies to Improve Active Case Finding in Community Tuberculosis Care in Botswana 2016-2021
4
作者 Unami Modongo-Mathebula Mary Moleki Tefera Agizew 《Journal of Tuberculosis Research》 2024年第2期105-118,共14页
Background: The community tuberculosis care program was started to reduce the impact of TB and increase successful treatment outcomes, thus contributing to meeting WHO targets on TB. According to the Botswana Ministry... Background: The community tuberculosis care program was started to reduce the impact of TB and increase successful treatment outcomes, thus contributing to meeting WHO targets on TB. According to the Botswana Ministry of Health, community tuberculosis care was introduced with the main goal of reducing tuberculosis-related morbidity and mortality among communities through the expansion of direct observed therapy and community involvement to community settings. The community caregivers were to support tuberculosis patients throughout their treatment period until they were cured or had completed their treatment. Settings: Two major cities of Botswana, Francistown and Gaborone, with more than twenty-two health clinics offering tuberculosis care. Objective: To investigate community caregivers’ experiences and identify programmatic strategies to improve active TB case findings under the community TB care (CTBC) program in Botswana during 2016-2021. Methods: We adopted a descriptive qualitative research design, followed by convenience purposive sampling. We obtained consent and interviewed 40 participants who met the inclusion criteria, 16 out of 73 in Gaborone and 24 out of 38 from Francistown. Results: We interviewed 40 caregivers with a mean age of 43.4 years. Accepting the caregiving role was identified as the main experience by more than two thirds of the caregivers. While at least more than two-fifth felt obligated to care for the patient at home due to personal relations. More than half of the respondents found caregiving difficult or frustrating due to some challenges encountered during the caregiving role. Behavioral modifications were suggested under different subthemes as strategies to improve active case finding. [-rId13-]Conclusion: Acceptance was the major experience in CTBC. Intensification of known programmatic strategies was suggested by caregivers to improve tuberculosis active case finding in CTBC. 展开更多
关键词 community Experiences CAREGIVERS Active Case Finding TUBERCULOSIS community Tuberculosis Care
下载PDF
Macroinvertebrate Community Index (MCI) and Quantitative Macroinvertebrate Community Index (QMCI) Analysis: A Comparative Study between Le Afe and Mulivaifagatoloa Rivers, Upolu Island, Samoa
5
作者 S. Taupega-Satau P. Amosa +2 位作者 A. Leauga J. Nunufolau T. Veni Nun Yan 《Journal of Geoscience and Environment Protection》 2024年第8期149-167,共19页
The diversity of Samoa’s freshwater macroinvertebrates remains largely unexplored, with past studies focusing on specific species without comprehensive cataloguing. This research evaluated the health of Upolu Island... The diversity of Samoa’s freshwater macroinvertebrates remains largely unexplored, with past studies focusing on specific species without comprehensive cataloguing. This research evaluated the health of Upolu Island’s rural rivers through macroinvertebrate analysis, particularly in the Le Afe and Mulivaifagatoloa Rivers. Collaborating with Samoa’s Water Resources Division in the Ministry of Natural Resources and Environment (MNRE), three sites along each river were sampled, representing a gradient from pristine to anthropogenically impacted areas. A total of 2953 macroinvertebrates were collected and classified into five categories using established identification keys. The Macroinvertebrate Community Index (MCI) and Quantitative Macroinvertebrate Community Index (QMCI) were applied for analysis. The results showed no clear pattern of pollutant-sensitive species prevalence or decline in less disturbed rivers. High MCI scores with low QMCI values indicated numerous low-scoring species, while the opposite suggested a richness of high-scoring taxa. Although MCI and QMCI are tools for monitoring freshwater health, this study lays the groundwork for future research to categorize Samoan macroinvertebrates and assign tolerance scores based on their presence in varying river conditions. . 展开更多
关键词 MACROINVERTEBRATES Macroinvertebrate community Index (MCI) Quantitative Macroinvertebrate community Index (QMCI) Water Quality
下载PDF
Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community:a comparative analysis 被引量:2
6
作者 Guolong Zhao Biao Zhao +5 位作者 Wenfeng Ding Lianjia Xin Zhiwen Nian Jianhao Peng Ning He Jiuhua Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期190-271,共82页
The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,su... The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,such as thin-walled structures,microchannels,and complex surfaces.Mechanical machining is the main material removal process for the vast majority of aerospace components.However,many problems exist,including severe and rapid tool wear,low machining efficiency,and poor surface integrity.Nontraditional energy-assisted mechanical machining is a hybrid process that uses nontraditional energies(vibration,laser,electricity,etc)to improve the machinability of local materials and decrease the burden of mechanical machining.This provides a feasible and promising method to improve the material removal rate and surface quality,reduce process forces,and prolong tool life.However,systematic reviews of this technology are lacking with respect to the current research status and development direction.This paper reviews the recent progress in the nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in the aerospace community.In addition,this paper focuses on the processing principles,material responses under nontraditional energy,resultant forces and temperatures,material removal mechanisms,and applications of these processes,including vibration-,laser-,electric-,magnetic-,chemical-,advanced coolant-,and hybrid nontraditional energy-assisted mechanical machining.Finally,a comprehensive summary of the principles,advantages,and limitations of each hybrid process is provided,and future perspectives on forward design,device development,and sustainability of nontraditional energy-assisted mechanical machining processes are discussed. 展开更多
关键词 difficult-to-cut materials geometrically complex components nontraditional energy mechanical machining aerospace community
下载PDF
Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil 被引量:1
7
作者 Minghui Cao Yan Duan +6 位作者 Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期698-710,共13页
Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidif... Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies. 展开更多
关键词 FERTILIZATION manure substitution soil fertility maize yield bacterial community
下载PDF
Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China 被引量:1
8
作者 Minzhe Fang Changjin Cheng +2 位作者 Nianpeng He Guoxin Si Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期1-11,共11页
Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations... Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods. 展开更多
关键词 BIOME-BGC community traits Forest Ecosystems Model parameterization
下载PDF
Insights into microbiota community dynamics and flavor development mechanism during golden pomfret(Trachinotus ovatus)fermentation based on single-molecule real-time sequencing and molecular networking analysis 被引量:1
9
作者 Yueqi Wang Qian Chen +5 位作者 Huan Xiang Dongxiao Sun-Waterhouse Shengjun Chen Yongqiang Zhao Laihao Li Yanyan Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期101-114,共14页
Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the ... Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products. 展开更多
关键词 Fermented golden pomfret Microbiota community Volatile compound Co-occurrence network Metabolic pathway
下载PDF
Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020 被引量:1
10
作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang... Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure. 展开更多
关键词 community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
下载PDF
Plant community on a volcano mountaintop reveals unique high-altitude vegetation in southeastern Brazil
11
作者 Igor Musauer KESSOUS Ruy JoséValka ALVES +1 位作者 Nílber Gonçalves da SILVA Amilcar Walter SAPORETTI JUNIOR 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3018-3030,共13页
Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be challenging.Similar to islands,species isolation in mountainous regions results in comparable patterns of evoluti... Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be challenging.Similar to islands,species isolation in mountainous regions results in comparable patterns of evolution and extinction,rendering their biodiversity unique and highly susceptible to anthropogenic threats.The topographic relief in mountains plays a crucial role in creating habitat complexity,which in turn contribute to high plant diversity.Here,we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau,a region situated in the ecotone between the Atlantic Forest and Cerrado,characterized by natural radiation and significant anthropogenic intervention.We employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the region.Additionally,we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the Cerrado.The plateau exhibits high plant diversity,including 1,659 specific and infraspecific taxa,especially belonging to Asteraceae and Poaceae.Our analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres,despite being associated with campos de altitude.The region possesses a unique set of biodiversity,indicating that it may be a distinct formation.Additionally,we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic Forest.Our study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing. 展开更多
关键词 Atlantic Forest BIOGEOGRAPHY CERRADO community ecology GRASSLAND
下载PDF
Effect of land use on soil nematode community composition and co-occurrence network relationship
12
作者 Xiaotong Liu Siwei Liang +3 位作者 Yijia Tian Xiao Wang Wenju Liang Xiaoke Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2807-2819,共13页
Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,for... Land use influences soil biota community composition and diversity,and then belowground ecosystem processes and functions.To characterize the effect of land use on soil biota,soil nematode communities in crop land,forest land and fallow land were investigated in six regions of northern China.Generic richness,diversity,abundance and biomass of soil nematodes was the lowest in crop land.The richness and diversity of soil nematodes were 28.8and 15.1%higher in fallow land than in crop land,respectively.No significant differences in soil nematode indices were found between forest land and fallow land,but their network keystone genera composition was different.Among the keystone genera,50%of forest land genera were omnivores-predators and 36%of fallow land genera were bacterivores.The proportion of fungivores in forest land was 20.8%lower than in fallow land.The network complexity and the stability were lower in crop land than forest land and fallow land.Soil pH,NH_(4)^(+)-N and NO_(3)^(–)-N were the major factors influencing the soil nematode community in crop land while soil organic carbon and moisture were the major factors in forest land.Soil nematode communities in crop land influenced by artificial management practices were more dependent on the soil environment than communities in forest land and fallow land.Land use induced soil environment variation and altered network relationships by influencing trophic group proportions among keystone nematode genera. 展开更多
关键词 soil nematode trophic groups community composition co-occurrence network land use
下载PDF
The microbial community,nutrient supply and crop yields differ along a potassium fertilizer gradient under wheat-maize double-cropping systems
13
作者 Zeli Li Fuli Fang +10 位作者 Liang Wu Feng Gao Mingyang Li Benhang Li Kaidi Wu Xiaomin Hu Shuo Wang Zhanbo Wei Qi Chen Min Zhang Zhiguang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3592-3609,共18页
Soil microorganisms play critical roles in ecosystem function.However,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains unclear.In thi... Soil microorganisms play critical roles in ecosystem function.However,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains unclear.In this long-term field experiment(2008-2019),we researched bacterial and fungal diversity,composition,and community assemblage in the soil along a K fertilizer gradient in the wheat season(K0,no K fertilizer;K1,45 kg ha^(-1) K_(2)O;K_(2),90 kg ha^(-1)K_(2)O;K3,135 kg ha^(-1)K_(2)O)and in the maize season(K0,no K fertilizer;K_(1),150 kg ha^(-1) K_(2)O;K_(2),300 kg ha^(-1)K_(2)O;K_(3),450 kg ha^(-1)K_(2)O)using bacterial 16S rRNA and fungal internally transcribed spacer(ITS)data.We observed that environmental variables,such as mean annual soil temperature(MAT)and precipitation,available K,ammonium,nitrate,and organic matter,impacted the soil bacterial and fungal communities,and their impacts varied with fertilizer treatments and crop species.Furthermore,the relative abundance of bacteria involved in soil nutrient transformation(phylum Actinobacteria and class Alphaproteobacteria)in the wheat season was significantly increased compared to the maize season,and the optimal K fertilizer dosage(K2 treatment)boosted the relative bacterial abundance of soil nutrient transformation(genus Lactobacillus)and soil denitrification(phylum Proteobacteria)bacteria in the wheat season.The abundance of the soil bacterial community promoting root growth and nutrient absorption(genus Herbaspirillum)in the maize season was improved compared to the wheat season,and the K2 treatment enhanced the bacterial abundance of soil nutrient transformation(genus MND1)and soil nitrogen cycling(genus Nitrospira)genera in the maize season.The results indicated that the bacterial and fungal communities in the double-cropping system exhibited variable sensitivities and assembly mechanisms along a K fertilizer gradient,and microhabitats explained the largest amount of the variation in crop yields,and improved wheat?maize yields by 11.2-22.6 and 9.2-23.8%with K addition,respectively.These modes are shaped contemporaneously by the different meteorological factors and soil nutrient changes in the K fertilizer gradients. 展开更多
关键词 potassium fertilizer gradient microbial community wheat-maize double cropping climate change yield
下载PDF
Zooplankton community response to eddy during dinoflagellate Noctiluca scintillans blooms off Pakistan,northern Arabian Sea
14
作者 Mahugnon Boris DEDO Xiping LIAN +2 位作者 Kaizhi LI Chenhui XIANG Yehui TAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1557-1570,共14页
Eddies are major elements of ocean dynamics that affect ocean production.Understanding their effects on plankton distribution may help understand the dynamics of harmful phytoplankton blooms.Previous studies on the ef... Eddies are major elements of ocean dynamics that affect ocean production.Understanding their effects on plankton distribution may help understand the dynamics of harmful phytoplankton blooms.Previous studies on the effects of eddies in the northern Arabian Sea have primarily focused on the zooplankton community,and few have observed zooplankton dynamics during winter blooms of Noctiluca scintillans.We investigated zooplankton community structure and the related environmental variability during a N.scintillans bloom that was affected by an eddy in February 2018.The sampling stations were deployed at eddy core and eddy edge distinguished in salinity,temperature,and velocity.Results show that N.scintillans bloomed at the eddy core with high-velocity currents induced by warm eddies that moved from eddy core to eddy edge.As a result,blooms significantly changed the zooplankton community structure.Non-bloom stations had higher zooplankton diversity than bloom stations.Zooplankton at non-bloom stations were dominated by either tunicates or copepods,such as Thalia democratica and Pleuromamma gracilis.In addition to the influence of N.scintillans blooms,the velocity of eddy currents was a crucial factor on the similarities in the zooplankton community composition between eddy edge and eddy core.Moreover,the lower abiotic factors in bloom area contribute to the structuring of the zooplankton community during N.scintillans blooms. 展开更多
关键词 EDDY zooplankton community Noctiluca scintillans northern Arabian Sea
下载PDF
Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem
15
作者 HAO Aihua LUO Zhengming CHEN Xiaojiang 《Journal of Mountain Science》 SCIE CSCD 2024年第1期146-159,共14页
Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradient... Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity. 展开更多
关键词 Warming effect Plant diversity pattern community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai
下载PDF
Dynamic analysis of major public health emergency transmission considering the dual-layer coupling of community–resident complex networks
16
作者 杨鹏 范如国 +1 位作者 王奕博 张应青 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期158-169,共12页
We construct a dual-layer coupled complex network of communities and residents to represent the interconnected risk transmission network between communities and the disease transmission network among residents. It cha... We construct a dual-layer coupled complex network of communities and residents to represent the interconnected risk transmission network between communities and the disease transmission network among residents. It characterizes the process of infectious disease transmission among residents between communities through the SE2IHR model considering two types of infectors. By depicting a more fine-grained social structure and combining further simulation experiments, the study validates the crucial role of various prevention and control measures implemented by communities as primary executors in controlling the epidemic. Research shows that the geographical boundaries of communities and the social interaction patterns of residents have a significant impact on the spread of the epidemic, where early detection, isolation and treatment strategies at community level are essential for controlling the spread of the epidemic. In addition, the study explores the collaborative governance model and institutional advantages of communities and residents in epidemic prevention and control. 展开更多
关键词 propagation dynamics complex networks public health events community structure
下载PDF
Oils with different degree of saturation:effects on ileal digestibility of fat and corresponding additivity and bacterial community in growing pigs
17
作者 Lu Wang Yifan Chen +2 位作者 Yuansen Yang Nuo Xiao Changhua Lai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1657-1668,共12页
Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of o... Background Oils are important sources of energy in pig diets.The combination of oils with different degree of saturation contributes to improve the utilization efficiency of the mixed oils and may reduce the cost of oil supplemented.An experiment was conducted to evaluate the effects of oils with different degree of saturation on the fat digestibility and corresponding additivity and bacterial community in growing pigs.Methods Eighteen crossbred(Duroc×Landrace×Yorkshire)barrows(initial body weight:29.3±2.8 kg)were surgically fitted with a T-cannula in the distal ileum.The experimental diets included a fat-free basal diet and 5 oil-added diets.The 5 oil-added diets were formulated by adding 6%oil with different ratio of unsaturated to saturated fatty acids(U:S)to the basal diet.The 5 oils were palm oil(U:S=1.2),canola oil(U:S=12.0),and palm oil and canola oil were mixed in different proportions to prepare a combination of U:S of 2.5,3.5 and 4.5,respectively.Results The apparent and standardized ileal digestibility(AID and SID)of fat and fatty acids increased linearly(P<0.05)as the U:S of dietary oils increased except for SID of fat and C18:2.The AID and SID of fat and fatty acids differed among the dietary treatments(P<0.05)except for SID of unsaturated fatty acids(UFA)and C18:2.Fitted one-slope broken-line analyses for the SID of fat,saturated fatty acids(SFA)and UFA indicated that the breakpoint for U:S of oil was 4.14(R^(2)=0.89,P<0.01),2.91(R^(2)=0.98,P<0.01)and 3.84(R^(2)=0.85,P<0.01),respectively.The determined SID of fat,C18:1,C18:2 and UFA in the mixtures was not different from the calculated SID of fat,C18:1,C18:2 and UFA.However,the determined SID of C16:0,C18:0 and SFA in the mixtures were greater than the calculated SID values(P<0.05).The abundance of Romboutsia and Turicibacter in pigs fed diet containing palm oil was greater than that in rapeseed oil treatment group,and the two bacteria were negatively correlated with SID of C16:0,C18:0 and SFA(P<0.05).Conclusions The optimal U:S for improving the utilization efficiency of mixed oil was 4.14.The SID of fat and UFA for palm oil and canola oil were additive in growing pigs,whereas the SID of SFA in the mixture of two oils was greater than the sum of the values of pure oils.Differences in fat digestibility caused by oils differing in degree of saturation has a significant impact on bacterial community in the foregut. 展开更多
关键词 ADDITIVITY Bacterial community Fat and fatty acids Growing pigs Ratio of unsaturated to saturated fatty acids Standardized ileal digestibility
下载PDF
Effects of potassium lactate on sensory attributes,bacterial community succession and biogenic amines formation in Rugao ham
18
作者 Renyong Liao Ying Wang +4 位作者 Qiang Xia Changyu Zhou Fang Geng Daodong Pan Jinxuan Cao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期198-210,共13页
To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community a... To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate. 展开更多
关键词 Rugao ham Potassium lactate Biogenic amines Microbial community Metabolic pathways
下载PDF
A method for cleaning wind power anomaly data by combining image processing with community detection algorithms
19
作者 Qiaoling Yang Kai Chen +2 位作者 Jianzhang Man Jiaheng Duan Zuoqi Jin 《Global Energy Interconnection》 EI CSCD 2024年第3期293-312,共20页
Current methodologies for cleaning wind power anomaly data exhibit limited capabilities in identifying abnormal data within extensive datasets and struggle to accommodate the considerable variability and intricacy of ... Current methodologies for cleaning wind power anomaly data exhibit limited capabilities in identifying abnormal data within extensive datasets and struggle to accommodate the considerable variability and intricacy of wind farm data.Consequently,a method for cleaning wind power anomaly data by combining image processing with community detection algorithms(CWPAD-IPCDA)is proposed.To precisely identify and initially clean anomalous data,wind power curve(WPC)images are converted into graph structures,which employ the Louvain community recognition algorithm and graph-theoretic methods for community detection and segmentation.Furthermore,the mathematical morphology operation(MMO)determines the main part of the initially cleaned wind power curve images and maps them back to the normal wind power points to complete the final cleaning.The CWPAD-IPCDA method was applied to clean datasets from 25 wind turbines(WTs)in two wind farms in northwest China to validate its feasibility.A comparison was conducted using density-based spatial clustering of applications with noise(DBSCAN)algorithm,an improved isolation forest algorithm,and an image-based(IB)algorithm.The experimental results demonstrate that the CWPAD-IPCDA method surpasses the other three algorithms,achieving an approximately 7.23%higher average data cleaning rate.The mean value of the sum of the squared errors(SSE)of the dataset after cleaning is approximately 6.887 lower than that of the other algorithms.Moreover,the mean of overall accuracy,as measured by the F1-score,exceeds that of the other methods by approximately 10.49%;this indicates that the CWPAD-IPCDA method is more conducive to improving the accuracy and reliability of wind power curve modeling and wind farm power forecasting. 展开更多
关键词 Wind turbine power curve Abnormal data cleaning community detection Louvain algorithm Mathematical morphology operation
下载PDF
Responses of soil enzyme and microbial community under co-loading of different microplastics and sulfamethoxazole
20
作者 Huang Juan Chen Hsuan +2 位作者 Cao Meifang Ma Yixuan Qian Xiuwen 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期275-285,共11页
Polyamide/polyethylene(PA/PE)microplastics were injected into soil containing sulfamethoxazole(SMX)to investigate their combined effects on SMX removal,soil enzyme activity,and microbial communities.The results show t... Polyamide/polyethylene(PA/PE)microplastics were injected into soil containing sulfamethoxazole(SMX)to investigate their combined effects on SMX removal,soil enzyme activity,and microbial communities.The results show that both PA and PE transiently increase SMX removal and inhibite the stimulation of microbial species diversity by SMX.The effect of PE is more significant.Meanwhile,PE combined with SMX increases the relative abundances of Actinobacteria and Pseudomonas,while PA combined with SMX decreases the relative abundances of Nocardioides and Streptomyces.In addition,PA/PE combined with SMX can increase dehydrogenase,urease,ammonia monooxygenase,and nitrate reductase activities in the soil while inhibiting the activity of laccase.Compared with PA combined with SMX,the activities of dehydrogenase,urease,ammonia monooxygenase,and laccase of PE combined with SMX increase by 9.82%,10.41%,8.07%,and 5.47%,while the activities of nitrate reductase and neutral phosphatase decrease by 1.47%and 6.78%. 展开更多
关键词 microplastics SULFAMETHOXAZOLE combined effect soil enzyme microbial community
下载PDF
上一页 1 2 187 下一页 到第
使用帮助 返回顶部