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temporal changes in soil bacterial and archaeal communities with different fertilizers in tea orchards

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第11期15卷 953-965页

作者： Hua WANG Shao-hui YANG Jing-ping YANG Ya-min LV Xing ZHAO Ji-liang PANG Institute of Environmental Protection College of Environmental and Resource Sciences Zhejiang University College of Life and Environmental Sciences Hangzhou Normal University

It is important to understand the effects of temporal changes in microbial communities in the acidic soils of tea orchards with different fertilizers. A field experiment involving organic fertilizer （OF）, chemical fertilizer （CF）, and unfertilized control （CK） treatments was arranged to analyze the temporal changes in the bacterial and archaeal communities at bimonthly intervals based on the 16S ribosomal RNA （rRNA） gene using terminal restriction fragment length polymorphism （T-RFLP） profiling. The abundances of total bacteria, total archaea, and selected functional genes （bacterial and archaeal amoA, bacterial narG, nirK, nirS, and nosZ） were determined by quantitative poly- merase chain reaction （qPCR）. The results indicate that the structures of bacterial and archaeal communities varied significantly with time and fertilization based on changes in the relative abundance of dominant T-RFs. The abundancy of the detected genes changed with time. The total bacteria, total archaea, and archaeal amoA were less abundant in July. The bacterial amoA and denitrifying genes were less abundant in September, except the nirK gene. The OF treatment increased the abundance of the observed genes, while the CF treatment had little influence on them. The soil temperature significantly affected the bacterial and archaeal community structures. The soil moisture was signif- icantly correlated with the abundance of denitrifying genes. Of the soil chemical properties, soil organic carbon was the most important factor and was significantly correlated with the abundance of the detected genes, except the nirK gene. Overall, this study demonstrated the effects of both temporal alteration and organic fertilizer on the structures of mi- crobial communities and the abundance of genes involved in the nitrogen cycle.

关键词： Bacterial and archaeal communities Fertilizer Soil temporal changes Tea orchard Functional genes

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Detecting remotely triggered temporal changes around the Parkfield section of the San Andreas fault

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Earthquake Science 2010年第5期23卷 497-509页

作者： Peng Zhao Zhigang Peng Karim Ghazi Sabra School of Earth and Atmospheric Science Georgia Institute of Technology Atlanta GA 30338 USA School of Mechanical Engineering Georgia Institute of Technology Atlanta GA 30338 USA

Detecting temporal changes in fault zone properties at seismogenic depth have been a long-sought goal in the seismological community for many decades. Recent studies based on waveform analysis of repeating earthquakes have found clear temporal changes in the shallow crust and around active fault zones associated with the occurrences of large nearby and teleseismic earthquakes. However, repeating earthquakes only occur in certain locations and their occurrence times cannot be controlled, which may result in inadequate sampling of the interested regions or time periods. Recent developments in passive imaging via auto- and cross-correlation of ambient seismic wavefields （e.g., seismic noise, earthquake coda waves） provide an ideal source for continuous monitoring of temporal changes around active fault zones. Here we conduct a systematic search of temporal changes along the Parkfield section of the San Andreas fault by cross-correlating relatively high-frequency （0.4-1.3 Hz） ambient noise signals recorded by 10 borehole stations in the High Resolution Seismic Network. After using stretch/compressed method to measure the delay time and the decorrelation-index between the daily noise cross-correlation functions （NCCFs）, we find clear temporal changes in the median seismic velocity and decorrelation-index associated with the 2004 M6.0 Parkfield earthquake. We also apply the same procedure to the seismic data around five regional/teleseismic events that have triggered non-volcanic tremor in the same region, but failed to find any clear temporal changes in the daily NCCFs. The fact that our current technique can detect temporal changes from the nearby but not regional and teleseismic events, suggests that temporal changes associated with distance sources are very subtle or localized so that they could not be detected within the resolution of the current technique （-0.2%）.

关键词： temporal changes remote triggering seismic noise cross-correlation interferometry seismic coda

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Assessment of temporal changes in Water Quality on Selected Parameters in Cole Mere

Assessment of Temporal Changes in Water Quality on Selected ...

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作者： Surajo Aminu Usman Aminu Ahmed Aliko Abba Sabo Department of Biology Jigawa State College of Education Department of Plant Biology Bayero University

temporal variability in some water quality parameters were investigated through field test and laboratory analysis in Cole Mere over the summer months(June,July and August) of 2013.A total of 10 sites were selected(within the lake) and sampled at approximately month *** surface water temperature recorded in June,July and August samplings were 14.1°C,21.9°C and 18.2°C *** differences in the mean temperature were statistically significant(p=temporal variability and elevated summer chlorophyll a concentrations are clear indications of eutrophic ***,no significant differences were recorded with regards to p H and dissolved oxygen between the months.

关键词： Chlorophyll cole mere eutrophication temporal changes

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Analysis of the temporal and spatial distribution of water quality in China＇s major river basins, and trends between 2005 and 2010

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Frontiers of Earth Science 2015年第3期9卷 463-472页

作者： Jinjian LI Xiaojie MENG Yan ZHANG Juan LI Linlin XIA Hongmei ZHENG State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

In this study, based on environmental quality monitoring data on 22 pollutants from 490 control sections, we analyzed the spatial distribution and temporal changes of water quality in ten Chinese river basins （watersheds） to reveal the trends from 2005 to 2010. We used a comprehensive water pollution index （WPI） and the proportions of this index accounted for by the three major pollutants to analyze how economic development has influenced water quality. Higher values of the index represent more serious pollution. We found that WPI was much higher for the Hai River Basin （1.83 to 5.60 times the averages in other regions）. In the Yangtze River Basin, WPI increased from upstream to downstream. The indices of some provinces toward the middle of a basin, such as Hebei Province in the Hal River Basin, Shanxi Province in the Yellow River Basin, and Anhui Province in the Huai River Basin, were higher than those of upstream and downstream provinces. In the Songhua, Liao, and South- east river basins, WPI decreased during the study period： in 2010, it decreased by 33.9%, 44.3%, and 67.2%, respectively, compared with the 2005 value. In the Pearl River, Southwest, and Inland river basins, WPI increased by 23.1%, 47.7%, and 38.5% in 2010, compared with 2005. A comparison of WPI with the GDP of each province showed that the water pollution generated by economic development was lightest in northwestern, southwestern, and northeastern China, and highest in central and eastern China, and that the water environment in some coastal regions were improving. However, some provinces （e.g., Shanxi Province） were seriously polluted.

关键词： water environment temporal changes spatial

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Empirical changes in the Prevalence of Overweight and Obesity among Chinese Students from 1985 to 2010 and Corresponding Preventive Strategies

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Biomedical and Environmental Sciences 2013年第1期26卷 1-12页

作者： JI Cheng Ye CHEN Tian Jiao Working Group on Obesity in China (WGOC) Institute of Child and Adolescent Health School of Public Health Peking University Health Science CenterBeijing 100191 China Institute of Child and Adolescent Health School of Public Health Peking UniversityHealth Science Center Beijing 100191 China' 3. WGOC.' Working Group on Obesity in China International LifeSciences Institute Focal Point in China WGOC: Working Group on Obesity in China International LifeSciences Institute Focal Point in China

Objective To determine the extent of the obesity epidemic in school‐aged Chinese children in 2010 and track the increasing trend in different socioeconomic regions over the preceding 25 years. Strategies for preventing childhood obesity are suggested. Methods We used a dataset provided by the Chinese National Survey on Students’ Constitution and Health from 1985‐2010. Subjects were 7‐18‐year‐old students randomly selected from urban and rural areas in 30 provinces. Eight subgroups were created according to region and socioeconomic status. Results Increased rates of the epidemic （overweight and obesity combined） were greatest in large coastal cities‐32.6% and 19.1% among males and females, respectively. These rates has neared that of developed countries. Similar increases were found in all other regions, including the once poverty‐stricken rural west. The epidemic in most of the rural areas began after 2000, but has spread swiftly over the last decade. In 2010, it was estimated that 9.9% of Chinese school‐aged children and adolescents were overweight and that an additional 5.1% were obese, representing an estimated 30.43 million individuals. Conclusion The prognosis for China＇s childhood‐obesity epidemic is dire. To prevent childhood obesity, we suggest several strategies, including reasonable dietary intake, increase physical activity, a change in sedentary lifestyles and corresponding behavioral modifications.

关键词： Obesity Chinese school‐aged children Prevalence temporal changes Socioeconomic status

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Tear inflammation related indexes after cataract surgery in elderly patients with type 2 diabetes mellitus

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World Journal of Clinical Cases 2023年第2期11卷 385-393页

作者： Jun Lv Cheng-Jian Cao Wei Li Shuang-Le Li Jun Zheng Xiu-Li Yang Department of Optometry North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina Zigong Academy of Medical Sciences Zigong First People’s HospitalZigong 643000Sichuan ProvinceChina FB Biologie Philipps-Universitaet MarburgMarburg 35043Germany Department of Ophthalmology Zigong First People’s HospitalZigong 643000Sichuan ProvinceChina

BACKGROUND Quantitative studies on the changes in inflammation-related content in tears,especially the effect of diabetes,are *** this study,we measured the preoperative and postoperative tear inflammatory mediator levels in cataract patients,focusing on the expression of inflammatory factors in postoperative cataracts in the diabetic,and investigated the effect of drugs on the control of postoperative *** To study the expression of inflammatory factors in elderly people with type 2 diabetes after cataract *** Patients with a mean age of 70.3±6.3 years were divided into group A(composed of elderly patients with cataracts and type 2 diabetes,n=20 eyes)and group B(patients with age-related cataract,n=20 eyes).Their tears were collected before each operation and on days 1 and 3,and weeks 1,2,3,and 4 ***(150μL)was dropped into the conjunctival sac of the surgical eye,followed by oculogyration in four *** fluid in the conjunctival sac was extracted using a sterile syringe and stored in Eppendorf tubes at-80°C until *** expression levels of matrix metalloproteinase-2(MMP-2),MMP-9,tissue inhibitor of metalloproteinase-1(TIMP-1),TIMP-2,interleukin-6(IL-6),and IL-20 in tear fluid were measured using enzyme-linked immunosorbent *** The postoperative expression levels of MMP-2,MMP-9,TIMP-2,IL-6,and IL-20 in group A were significantly higher than those in group B,whereas the concentration of TIMP-1 in group A remained lower than that in group *** levels of MMP-2 and IL-6 in both groups continuously increased until the peak in the first postoperative week,and then gradually decreased over the next three ***,MMP-2 declined to a lower level than that preoperatively at week 4,but IL-6 decreased to the same level as that *** level of MMP-9 peaked in the first two weeks postoperative and then returned to the same level as 1-day *** concentration of TIMP-1 pos

关键词： Type 2 diabetes mellitus Elderly patients Cataract surgery Tear inflammation-related indicators temporal changes Prognosis

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Recent advances in imaging crustal fault zones: a review

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Earthquake Science 2015年第2期28卷 151-162页

作者： Hongfeng Yang Earth System Science Programme The Chinese University of Hong Kong

Crustal faults usually have a fault core and surrounding regions of brittle damage, forming a low-velocity zone （LVZ） in the immediate vicinity of the main slip interface. The LVZ may amplify ground motion, influence rupture propagation, and hold important information of earthquake physics. A number of geophysical and geodetic methods have been developed to derive high-resolution structure of the LVZ. Here, I review a few recent approaches, including ambient noise cross-correlation on dense across-fault arrays and GPS recordings of fault-zone trapped waves. Despite the past efforts, many questions concerning the LVZ structure remain unclear, such as the depth extent of the LVZ. High-quality data from larger and denser arrays and new seismic imaging technique using larger portion of recorded waveforms, which are currently under active development, may be able to better resolve the LVZ structure. In addition, effects of the alongstrike segmentation and gradational velocity changes across the boundaries between the LVZ and the host rock on rupture propagation should be investigated by conducting comprehensive numerical experiments. Furthermore, high-quality active sources such as recently developed large-volume airgun arrays provide a powerful tool to continuously monitor temporal changes of fault-zone properties, and thus can advance our understanding of fault zone evolution.

关键词： Fault zone structure Fault zone waves Earthquake rupture temporal changes

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Illuminating high-resolution crustal fault zones using multi-scale dense arrays and airgun source

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Earthquake Research Advances 2021年第1期1卷 10-18页

作者： Hongfeng Yang Yaohui Duan Junhao Song Weitao Wang Wei Yang Xiaofeng Tian Baoshan Wang Earth System Science Programme Faculty of ScienceThe Chinese University of Hong KongHong KongChina Shenzhen Research Institute The Chinese University of Hong KongShenzhenChina Institute of Geophysics China Earthquake AdministrationBeijingChina Center of Geophysical Exploration China Earthquake AdministrationZhengzhouChina School of Earth and Space Sciences University of Science and Technology of ChinaHefeiChina

High-resolution imaging of fault zone structure and its temporal changes can not only advance our understanding of earthquake physics,but is also critical for better seismic hazard preparation and *** the past a few years,we deployed multi-scale dense arrays across the Chenghai fault system in Binchuan,Yunnan,*** first array consisted of 381 intermediate-period three-component seismometers with an average station spacing of~2 *** array has been deployed in the field for~3 months in 2017 and recorded numerous local and teleseismic *** time analyses based on teleseismic earthquakes and an airgun source in the region indicated clear signature of low-velocity fault zones in the southern branch of the Chenghai fault *** 2018 we deployed two other linear arrays using the same instruments with much smaller inter-station spacing,e.g.30-50 m,across the southern branch the Chenghai *** profile lengths were 8 and 5 km,*** sections of the airgun source on the two linear arrays clearly marked a low-velocity zone(LVZ)within the southern array but no such signature in the northern array,suggesting along-strike variation of the *** the instruments within our dense arrays had an intermediate frequency band,we demonstrated that they were capable of characterizing crustal structure with techniques commonly applied to broadband signals such as receiver *** our best knowledge,this was the first time to have multi-scale across-fault dense arrays with three-component seismometers in such *** results lay out the pavement to comprehensively investigate fault zone structures as well as to derive subsurface structural changes using dense arrays and the airgun source.

关键词： Fault zone temporal changes Dense array Airgun source

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Characterizing selected soil attributes of different land-use management to assess reforestation benefits of deforested riparian buffers

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Ecological Processes 2018年第1期7卷 467-478页

作者： Velu Rasiah Singarayer K.Florentine Whispering Ridge Drive GuelphOntario N1G 3Z4Canada Centre for Environmental Management School of Health and Life SciencesFederation University AustraliaPO Box 663Mount HelenVIC 3350Australia

Introduction:The information available on the sensitivity of soil biotic and abiotic attributes,which can be used to track the impact of reforestation in riparian buffers,is often insufficient to refine management practices and convince stakeholders of the benefits of ***:In this study,conducted in Victoria,Australia,the changes in soil biotic and abiotic attributes,organic carbon(OC),mineral nitrogen(MN),total dissolved solutes(TDS)and pH were characterised to assess the impact of land-use change from bare riparian(BR)to reforested riparian(RR).Additionally,the benefits of revegetating a deforested creek bank with regard to salinity abatement and C-sequestration potentials were ***:The TDS depletion in the RR strips varied spatiotemporally from 65 to 169 mg/L,the net OC deposition from 16 to 19 g C/kg soil and MN deposition from 1.2 to 2.1 g N/kg soil,***,the net changes in pH from alkaline to near neutral condition varied by 0.4 to 1.0 pH *** 30%to 60%of the net OC depletion after deforestation was redeposited under RR over 3 to 6 *** TDS depletion after land-use changed from BR to RR ranged from 15 to 32%over 3 to 6 ***:The soil attributes OC,MN and TDS characteristics under different land-use practices varied *** information may be useful to convince stakeholders to undertake reforestation of creek banks for salinity abatement,and that change in land-use has the potential to increase C sequestration at a farm scale.

关键词： Creek bank riparian Deforestation Reforestation Soil biotic and abiotic attributes Site specificity temporal changes Carbon sequestration Soil salinity

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