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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
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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
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Effects of Biostimulation-Bioaugmentation on Coastal Microbial Community in an in situ Mesocosm System
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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
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The microbial community,nutrient supply and crop yields differ along a potassium fertilizer gradient under wheat-maize double-cropping systems
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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
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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem
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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
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Response of Bacterial Community and Enzyme Activity of Greenhouse Tomato under Different Irrigation Systems
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作者 Haijian Yang Mingzhi Zhang +1 位作者 Na Xiao Yuan Li 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1543-1568,共26页
The micro-sprinkler irrigation mulched(MSM)has been suggested as a novel water-saving approach in con-trolled environment agriculture.However,the effects of microbial community structure and enzyme activity in the rhi... The micro-sprinkler irrigation mulched(MSM)has been suggested as a novel water-saving approach in con-trolled environment agriculture.However,the effects of microbial community structure and enzyme activity in the rhizosphere soil on crop growth under MSM remain unclear.This study conducted a randomized experimen-tal design using greenhouse tomatoes to investigate changes in bacterial community structure and enzyme activity in rhizosphere soil under different irrigation frequencies(F)and amounts(I)of MSM.Thefindings revealed that with the increase of F or I,The total count of soil bacteria in tomatoesfirst rose and then fell in terms of Opera-tional Taxonomic Units(OTUs)classification.Compared to other F,the most abundance of nitrogen and phos-phorus metabolism genes and enzyme activities were observed with a 5-day F.Moreover,the diversity of soil bacterial community structure initially rose before eventually declining with the increase of the I.Applying 1.00 Epan(cumulative evaporation of a 20 cm standard pan)under MSM helped boost the abundance of nitrogen and phosphorus metabolism functional genes in soil bacteria,ensuring higher enzyme activities related to nitro-gen,carbon,and phosphorus metabolism in the rhizosphere soil of tomatoes.Tomatoes’yield initially rose before eventually declining with the increase in F or I,whereas I had a more significant effect on yield.A 1.00%increase in I yielded a minimum of 39.24%increase in tomato yield.The study showed a positive correlation between soil bacterial community,soil enzyme activity,and greenhouse tomato yield under MSM.Considering the results comprehensively,the combined irrigation mode of F of 5 d and I of 1.00 Epan was recommended for greenhouse tomatoes under MSM.This conclusion provides theoretical support for water-saving practices and yield improve-ment in facility agriculture,especially tomato cultivation. 展开更多
关键词 Greenhouse tomato YIELD bacterial community enzyme activity MODEL
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Systematic Review of Community Type 2 Diabetes Structured Health Education (CT2DSHE)
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作者 Gift Phiri 《Open Journal of Nursing》 2024年第8期377-400,共24页
Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming t... Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming to summarize the results of prior primary research studies on available evidence Community type 2 diabetes structured education (CT2DSHE). Methods: Research question: Type 2 diabetic structured health education within a community how effective is it? Qualitative Systematic review, defined as a way to get reliable and objective picture of current available evidence on the specific topic—(CT2DSHE), (Denscombe, 2021) through reflexivity synthesis of available data as an example. This is valuable in time constraints such as project assignments that must be met within specific time and also to bring together available evidence together [1]. Results: This review has shown that CT2DSHE is effective with seven out of the eleven authors supporting, three authors against and one was neutral, further showed that knowledge and skills acquired can last longer with patient activation improved among T2DM patients ideal for sustaining their self-management of T2DM. Conclusion: This research provides suggestive answers to the research question: “Type 2 diabetic structured health education within a community how effective is it?”, This has demonstrated CT2DSHE effectiveness in knowledge acquisition and improving T2DM awareness among T2DM patients, whilst evidencing long effects beyond the study times of 3 - 9 months period in relation to patient activation. Also Identified diabetes education self-management on newly diagnosed (DESMOND) patient as CT2DSHE program for recommendation. Patient or Public Contribution: This work aspires to contribute to CT2DSHE in these areas;Influencing policy decision-making for community diabetes care within the UK and world at large., Contributing to already vast knowledge on diabetes self-management and reasons why?, Influencing educators on how CT2DSHEP are designed, delivered by putting the patient at the Centre and bringing different perspectives on CT2DSHEP in one place that is serving users time of having to consult several resources especially busy clinicians [2] [3]. 展开更多
关键词 community Health EDUCATION EFFECTIVENESS Impact Structured and Planned Type 2 Diabetes (T2DM)
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Study on Construction Strategy of Rainwater Landscape System in Urban Residential Community
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作者 刘丽 刘晓青 《Agricultural Science & Technology》 CAS 2017年第12期2580-2582,共3页
On the basis of analyzing the function and restriction conditions of water features in residential community, the feasibility and specific strategies of using rain- water to construct the waterscape system in resident... On the basis of analyzing the function and restriction conditions of water features in residential community, the feasibility and specific strategies of using rain- water to construct the waterscape system in residential community were proposed, with the aim to deal with the problems of urban water shortage, urban waterlogging and initial rainwater non-point source pollution. 展开更多
关键词 Waterscape system Urban residential community CONSTRUCTION Facllltles
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Construction and application of an assessment index system for evalu ating the eco-community’s sustainability 被引量:1
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作者 韩英 代力民 +2 位作者 赵小汎 于大炮 吴胜男 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第2期154-158,共5页
An assessment index system including environment, socio-culture, economy and technology was established for evaluating environmental construction level of community (objective construction), and questionnaire was de... An assessment index system including environment, socio-culture, economy and technology was established for evaluating environmental construction level of community (objective construction), and questionnaire was designed according to paper review for evaluating residential satisfaction (subjective satisfaction). The index system was divided into four layers: system (A), subsystems (B), categories (C), and indicators (D), and in total of 38 indicators was established. The Xihe community, affiliated to Nanfen district, Benxi City, Liaoning Province, China was selected as a case study. Results indicated that the community sustainability index related to objective environmental construction was 0.4355 and was classified as class Ⅲ (moderate); the community sustainability index related to the residential satisfaction was 0.4255, belonging to class Ⅲ. In conclusion, the sustainability of Xihe community was moderate and needed to be improved. Residential satisfaction was lower than objective environmental construction. The assessment index system established in this study is able to reflect the comprehensive sustainability of community and can be used to evaluate other similar communities' sustainability. 展开更多
关键词 community sustainability assessment index system objective environmental construction residential satisfaction Xihe community
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Soil Microbial Community Structure in Diverse Land Use Systems:A Comparative Study Using Biolog,DGGE,and PLFA Analyses 被引量:56
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作者 XUE Dong YAO Huai-Ying +1 位作者 GE De-Yong HUANG Chang-Yong 《Pedosphere》 SCIE CAS CSCD 2008年第5期653-663,共11页
Biolog, 16S rRNA gene denaturing gradient gel electrophoresis (DGGE), and phospholipid fatty acid (PLFA) analyses were used to assess soil microbial community characteristics in a chronosequence of tea garden syst... Biolog, 16S rRNA gene denaturing gradient gel electrophoresis (DGGE), and phospholipid fatty acid (PLFA) analyses were used to assess soil microbial community characteristics in a chronosequence of tea garden systems (8-, 50-, and 90- year-old tea gardens), an adjacent wasteland, and a 90-year-old forest. Biolog analysis showed that the average well color development (AWCD) of all carbon sources and the functional diversity based on the Shannon index decreased (P 〈 0.05) in the following order: wasteland 〉 forest 〉 tea garden. For the DCCE analysis, the genetic diversity based on the Shannon index was significantly lower in the tea garden soils than in the wasteland. However, compared to the 90-year-old forest, the tea garden soils showed significantly higher genetic diversity. PLFA analysis showed that the ratio of Gram positive bacteria to Cram negative bacteria was significantly higher in the tea garden soils than in the wasteland, and the highest value was found in the 90-year-old forest. Both the fungal PLFA and the ratio of fungi to bacteria were significantly higher in the three tea garden soils than in the wasteland and forest, indicating that fungal PLFA was significantly affected by land-use change. Based on cluster analysis of the soil microbial community structure, all three analytical methods showed that land-use change had a greater effect on soil microbial community structure than tea garden age. 展开更多
关键词 BIOLOG DCCE microbial community structure PLFA tea garden soil
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Global Climate Internal Variability in a 2000-year Control Simulation with Community Earth System Model(CESM) 被引量:13
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作者 WANG Zhiyuan LI Yao +1 位作者 LIU Bin LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2015年第3期263-273,共11页
Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation ... Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation was carried out with fixed external forcing factors (1850 Common Era. (C.E.) conditions) for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation (ENSO), the Atlantic Multi-decadal Oscilla- tion (AMO), the Pacific Decadal Oscillation (PDO), and the North Atlantic Oscillation (NAO), were compared with reanalysis datasets to evaluate the model performance. The results are as follows: 1) CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2) climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3) the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM. 展开更多
关键词 community Earth system Model (CESM) climate simulation past 2000 years climate system intemal variability
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Some Limitations of BIOLOG System for Determining Soil Microbial Community 被引量:8
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作者 YAOHUAIYING C.D.CAMPBELL 《Pedosphere》 SCIE CAS CSCD 2000年第1期37-44,共8页
A laboratory experiment was conducted to evaluate the effect of triphenyltetrazolium chloride (TTC) on soil microorganisms and the availability of pH characterization medium in BIOLOG plates. Application of TTC decrea... A laboratory experiment was conducted to evaluate the effect of triphenyltetrazolium chloride (TTC) on soil microorganisms and the availability of pH characterization medium in BIOLOG plates. Application of TTC decreased the color development sharply and resulted in a great biocidal effect on the growth and reproduction of soil microorganisms, indicating that TTC can affect the discrimination on soil microbial community. The microtitration plates with 21 carbon sources and two different pH levels (4.7 and 7.0) were used to determine microbial community structure of eight red soils. The average utilization (average well colour development) of the carbon sources in the plates with different pH levels generally followed the same sigmoidal pattern as that in the traditional BIOLOG plates, but the pH 4.7 plates increased the discrimination of this technique, compared with the pH 7.0 plates. Since most tested soils are acid, it seemed that it’s better to use a suitable pH characterization medium for a specific soil in the sole carbon source test. 展开更多
关键词 BIOLOG microbial community red soil triphenyltetrazolium chloride
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Effects of a decade of organic fertilizer substitution on vegetable yield and soil phosphorus pools, phosphatase activities, and the microbial community in a greenhouse vegetable production system 被引量:8
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作者 ZHANG Yin-jie GAO Wei +5 位作者 LUAN Hao-an TANG Ji-wei LI Ruo-nan LI Ming-yue ZHANG Huai-zhi HUANG Shao-wen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第7期2119-2133,共15页
Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated th... Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices. 展开更多
关键词 organic substitution management soil P pools phosphatase activity microbial community soil C/P PLS-PM
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Effects of long-term straw incorporation on nematode community composition and metabolic footprint in a rice–wheat cropping system 被引量:3
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作者 CHEN Yun-feng XIA Xian-ge +4 位作者 HU Cheng LIU Dong-hai QIAO Yan LI Shuang-lai FAN Xian-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第8期2265-2276,共12页
Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,suc... Soil nematode communities can provide valuable information about the structure and functions of soil food webs,and are sensitive to agricultural practices,including short-term straw incorporation.However,currently,such effects under longterm straw incorporation conditions at different fertility levels are largely unknown.Thus,we conducted a 13-year ongoing experiment to evaluate the effects of long-term straw incorporation on the structure and functions of the soil food web in low and high fertility soils through analyzing its effects on nematode communities,food web indices and metabolic footprints.Four treatments were included:straw removal(–S)under non-fertilized(–NPK)or fertilized(+NPK)conditions;and straw incorporation(+S)under–NPK or+NPK conditions.Soil samples from a 0–20 cm depth layer were collected when wheat and rice were harvested.Compared with straw removal,straw incorporation increased the abundances of total nematodes,bacterivores,plant-parasites and omnivores-predators,as well the relative abundances of omnivores-predators with increases of 73.06,89.29,95.31,238.98,and 114.61%in–NPK soils and 16.23,2.23,19.01,141.38,and 90.23%in+NPK soils,respectively.Regardless of sampling times and fertilization effects,straw incorporation increased the diversity and community stability of nematodes,as indicated by the Shannon-Weaver diversity index and maturity index.Enrichment and structure index did not show significant responses to straw incorporation,but a slight increase was observed in the structure index.The analysis of nematode metabolic footprints showed that straw incorporation increased the plant-parasite footprint and structure footprint by 97.27 and 305.39%in–NPK soils and by 11.29 and 149.56%in+NPK soils,but did not significantly influence enrichment,bacterivore and fungivore footprints.In conclusion,long-term straw incorporation,particularly under a low fertility level,favored the soil nematodes and regulated the soil food web mainly via a top-down effect. 展开更多
关键词 soil nematodes community composition metabolic footprint straw incorporation rice-wheat cropping system top-down effect
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Wheat, maize and sunflower cropping systems selectively influence bacteria community structure and diversity in their and succeeding crop's rhizosphere 被引量:21
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作者 WEN Xin-ya Eric Dubinsky +2 位作者 WU Yao YU Rong CHEN Fu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第8期1892-1902,共11页
supported by the Special Fund for Agro-scientific Research in the Public Interest in China (201103001)
关键词 bacterial community structure and diversity rhizosphere cropping system 454 pyrosequencing
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A Model for Regional Energy Utilization by Offline Heat Transport System and Distributed Energy Systems—Case Study in a Smart Community, Japan 被引量:4
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作者 Liyang Fan Weijun Gao Zhu Wang 《Energy and Power Engineering》 2013年第3期190-205,共16页
Under the Kyoto Protocol,Japanwas supposed to reduce six percent of the green house gas (GHG) emission in 2012. However, until the year 2010, the statistics suggested that the GHG emission increased 4.2%. What is more... Under the Kyoto Protocol,Japanwas supposed to reduce six percent of the green house gas (GHG) emission in 2012. However, until the year 2010, the statistics suggested that the GHG emission increased 4.2%. What is more challenge is, afterFukushimacrisis, without the nuclear energy,Japanmay produce about 15 percent more GHG emissions than1990 inthis fiscal year. It still has to struggle to meet the target set by Kyoto Protocol. The demonstration area of “smart community” suggests Japanese exploration for new low carbon strategies. The study proposed a demand side response energy system, a dynamic tree-like hierarchical model for smart community. The model not only conveyed the concept of smart grid, but also built up a smart heat energy supply chain by offline heat transport system. Further, this model promoted a collaborative energy utilization mode between the industrial sector and the civil sector. In addition, the research chose the smart community inKitakyushuas case study and executed the model. The simulation and the analysis of the model not only evaluate the environmental effect of different technologies but also suggest that the smart community inJapanhas the potential but not easy to achieve the target, cut down 50% of the CO2 emission. 展开更多
关键词 Smart community DEMAND Side Response Distributed Energy system Reutilize FACTORY EXHAUST HEAT OFFLINE HEAT Transport system
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Insights into community-based bioassessment of environmental quality status using microphytobenthos in estuarine intertidal ecosystems 被引量:2
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作者 DU Guoying CHUNG Ik kyo XU Henglong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期112-120,共9页
The feasibility of community-based bioassessment of environmental quality status was studied using microphytobenthos(MPB) in estuarine intertidal ecosystems.The sediment samples of MPB were collected monthly during ... The feasibility of community-based bioassessment of environmental quality status was studied using microphytobenthos(MPB) in estuarine intertidal ecosystems.The sediment samples of MPB were collected monthly during a 1-year cycle(September 2006-August 2007) at four sampling stations in the Nakdong River Estuary,Korea.Environmental variables,such as salinity,radiation,grain size of sediment,Si(OH)4(Si),nitrate(NO3^-),nitrite(NO2^-),ammonium(NH4~+) and phosphates(PO4^(3-)),were measured synchronously for comparison with biotic parameters.The statistical analyses were carried out for assessment the relationship between biotic and environmental parameters.The results showed that:(1) the MPB community structures were significant differences among four sampling stations;(2) spatial variation in the MPB communities were significantly correlated with environmental variables,especially the nutrient NH4+ in combination with salinity and grain size;(3) three species(Navicula lacustris,Pleurosigma anglulatum and Fragilaria sp.1) were significantly correlated with nutrients and/or Si;and(4) the species richness and diversity were significantly correlated with the grain size.It is suggested that MPB communities may be used as a potentially robust bioindicator for assessing environmental quality status in estuarine intertidal ecosystems. 展开更多
关键词 marine bioassessment field community MICROPHYTOBENTHOS estuarine intertidal ecosystem Nakdong River
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Factors Affecting Patient Satisfaction with Community Health Service under the Gatekeeper System:A Cross-sectional Study in Nanjing,China 被引量:3
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作者 LI Wen Zhen GAN Yong +6 位作者 ZHOU Yan Feng CHEN Ya Wen LI Jing KKANDAWIRE Naomiem HU Sai QIAO Yan LU Zu Xun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第9期685-690,共6页
The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service(CHS) under the gatekee... The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service(CHS) under the gatekeeper system. Our study showed that the cognition of gatekeeper policy was associated with four dimensions including doctor‐patient relationships, information and support, organization of care, and accessibility(P 〈 0.001). One or more factors such as gender and self‐perceived health scores also affected their satisfaction. General practitioners must be prepared to focus on these aspects of information and support, organization of care, and accessibility as indicators of potential opportunities for improvement. Additionally, policymakers can improve patients' satisfaction with CHS by strengthening their awareness of the gatekeeper policy. 展开更多
关键词 CHS A Cross-sectional Study in Nanjing China Factors Affecting Patient Satisfaction with community Health Service under the Gatekeeper system
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Community structure and assembly of denitrifying bacteria in epiphytic biofilms in a freshwater lake ecosystem 被引量:2
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作者 Guoqing LI Dingbo YAN +3 位作者 Pinhua XIA Haipeng CAO Tao LIN Yin YI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第3期1039-1050,共12页
Denitrifying bacteria are a crucial component of aquatic ecosystem in nitrogen cycle.However,the denitrifying bacterial community dynamics and structure in epiphytic biofilms remain unexplored.The abundance of denitri... Denitrifying bacteria are a crucial component of aquatic ecosystem in nitrogen cycle.However,the denitrifying bacterial community dynamics and structure in epiphytic biofilms remain unexplored.The abundance of denitrification gene(nir)and structure of nirS-denitrifying bacterial community in the epiphytic biofilms collected in July and November of 2018 from a typical plateau lake(Caohai Wetland,Guizhou,China)were studied by Real-time Quantitative Polymerase Chain Reaction(qPCR)and highthroughput sequencing.Results show that the gene abundance of nirK was higher than that of nirS(P<0.05),and it was significantly different during the growth period(July)than the decline period(November).The denitrifying bacterial species was similar in the two months and shared 76.18%of OTUs.Proteobacteria(56.55%±22.15%)was the dominant phylum in all the samples.Epiphytic biofilms between growth period and decline period displayed significantly different microbial community structures due to differences in species abundance.Water temperature was the crucial factor that affected the denitrifying microbial community structure in our study.Environmental factors explain only partially the dynamic characteristics of denitrifying microbial communities,implying that the stochastic processes affected the construction of denitrifying microbial communities.As the null model analysis results show,dispersal limitation(stochastic)and undominated processes significantly influenced the assembly of denitrifying microbial communities.This study broadened our understanding of the denitrifying bacterial community structure and its function on epiphytic biofilms in freshwater ecosystems with new information provided. 展开更多
关键词 denitrifying bacteria epiphytic biofilms community assembly null model
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Understory flora and community physiognomy of planted forests in the degraded purple soil ecosystem, South China 被引量:1
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作者 YUZhan-yuan YUEYong-jie +4 位作者 GUOJian-fen CHENGuang-shui XIEJin-sheng HEZong-ming YANGYu-sheng 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期109-112,共4页
The flora and community physiognomy of degraded plantation ecosystems onpurple soil were investigated in Ninghua County of Fujian Province, China to understand therelationship between plant diversity and ecosystem pro... The flora and community physiognomy of degraded plantation ecosystems onpurple soil were investigated in Ninghua County of Fujian Province, China to understand therelationship between plant diversity and ecosystem processes.. Four different restorationcommunities (labeled as ecological restoration treatment Ⅰ, Ⅱ, Ⅲ and Ⅳ) were selected byspace-time replacement method according to the erosion intensity in degraded purple soil ecosystem.The results showed that there were totally 86 plant species belonging to 78 genera and 43 familiesin the degraded purple soil ecosystem. Of the 15 types of distribution area in spermatophyte genus,12 types were found in the purple soil ecosystem. Along restoration gradient from low to high, plantgrowth type and life form spectra became abundant more and more, and the spermatophyte genera foreach distribution area type and genera numbers for different foliage characters increased as well.It is concluded that the plant flora and physiognomy in ecological restoration process become morecomplex and diverse, indicating that the forest ecosystem on purple soil tends to be more stable. 展开更多
关键词 purple soil FLORA community physiognomy BIODIVERSITY ecosystem processes
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Characterization of Bacterial Community,Ammonia-Oxidizing Bacteria,and Nitrospira During the Operation of a Commercial-Scale Recirculating Aquaculture System for Culturing Pufferfish Takifugu rubripes 被引量:1
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作者 MA Yuexin YU Zichao +3 位作者 DU Xin ZHANG Tao WANG Ning TAO Wei 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第6期1399-1408,共10页
We investigated the changes in communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira during the operation of a pufferfish Takifugu rubripes recirculating aquaculture system by using high-throughput DNA seq... We investigated the changes in communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira during the operation of a pufferfish Takifugu rubripes recirculating aquaculture system by using high-throughput DNA sequencing.Differences in bacterial communities were observed at days 1-32,47-62 and 78-93 of biofilm development by using 16S rRNA gene pyrosequencing.The relative abundance of Proteobacteria(Gammaproteobacteria)increased,while that of Bacteroidetes(Flavobacteria)decreased.The proportions of Nitrosomonas and Nitrospina ranged from 0.02%to 0.30%and from 0.02%to 0.83%,respectively.Ammonia monooxygenase gene pyrosequencing revealed that the top three operational taxonomic units were related to Nitrosomonas aestuarii(17.5%-61.1%),uncultured beta proteobacterium clone B67S-54(1.9%-45.2%),and uncultured bacterium clone AZPa8(3.6%-24.7%).Nitrite oxidoreductase gene pyrosequencing revealed that the relative abundance of the dominant strain Nitrospira sp.Ecomares 2.1 increased,but that of the abundant species Nitrospira marina decreased.Our results demonstrated that the communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira were changing during the operation of the pufferfish recirculating aquaculture system. 展开更多
关键词 BIOFILTER bacterial community ammonia-oxidizing bacteria NITROSPIRA recirculating aquaculture system
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