Environment Promotion and Microclimate Improvement of Old Communities with Combination of Peacetime and Epidemic Situation: A Case Study of Fuguoli Community in Beijing

As the basic unit of a city,community is an important carrier of residents’ healthy life.With the development of society,the environmental status of old communities has been unable to meet the needs of residents’ healthy life,and it is urgent to optimize the community environment.The emergence of novel coronavirus also put forward more strict requirements for the grassroots governance of old communities in China.Taking Fuguoli community in Beijing City as an example,the problems existing in the external environment of old communities were excavated from the perspective of functional requirements,and the distributed green space layout pattern and the dynamic simulation of community microclimate environment was constructed through the method of field survey and numerical simulation.Furthermore,the environmental optimization strategies of old communities with combination of peacetime and epidemic situation were put forward to help the epidemic prevention and control.

Characteristic Town Environment Design Based on Brand Community——A Case Study of the Forest Hot Spring Township in Ninghai

Brand community is a specific,geographically-unconstrained community based on specific brands and is constructed with consumer groups of different levels,choices and territories. The development issues of characteristic towns were incorporated into the perspective of brand communities,and the development connotation of characteristic towns was discussed in light of the definition,constituent elements and characteristics of brand communities,and a functional platform with organic combination of industry,city,people and literature was established through the exploration of Ninghai forest hot spring town,combined with local spatial resources. Based on this,the planning and design of Ninghai forest hot spring town will form a characteristic town that integrates industrial functions,cultural functions and community functions.

Single and combined effects of secondary polyethylene microplastic on the growth of Pak choi and the soil microbiome composition

It has been confirmed that microplastics(MPs)are present in the environment.This study simulated secondary PE-MPs via aging and mechanical processes to evaluate their effects on Pak choi(Brassica rapa L.)over 21 d.Two common pollutants,dichlorodiphenyltrichloroethane(DDT)and naphthalene,were used in the combined toxicity tests.The results indicated that the growth of Pak choi was significantly inhibited after exposure to secondary PE-MPs,and the combined effects were antagonistic,owing to the adsorption capacity of secondary PE-MPs to DDT and naphthalene.Oxidative stress in Pak choi can be markedly affected,leading to oxidative damage to plant cells.The moisture content,soil bulk density,soil density,cation exchange capacity(CEC),and FDA hydrolase in the planted soils increased in the treated groups,and the TOC content changed significantly.We also found that the microbial composition of the soil in the DDT and naphthalene groups showed more significant alterations than that in the other groups.Alpha diversity analysis showed that species diversity increased in the combined groups but indicated a clear downward trend in the single MPs groups.This study suggests that secondary PE-MPs harm the growth of Pak choi and can change soil properties,revealing the harm to the ecosystem of MPs in the soil.

Impacts of methamidophos,copper,and their combinations on bacterial community structure and function in black soil

The potential ecotoxicologial risks of methamidophos,copper,and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rDNA-PCR-DGGE analysis approach,and functional characteristics at community levels by using BIOLOG^(GN) system analysis method as well as two conventional methods(DHA and SIR).All results of DGGE banding fingerprint patterns(amplified by bacterial specific 16S rDNA V_(3) high variable region universal primer)indicated that the species richness of bacterial community in tested soil was significantly decreased to different extents by using different concentrations of single methamidophos,copper,especially some of their combinations had worse effects than their corresponding single factors.In addition,the structures of soil bacterial community had been disturbed under all stresses applied in this study because of the enrichment of some species and the disappearance of other species from the bacterial community.The effects of the single factors with lower concentrations on the communiy structure were weaker than those with higher concentrations.Moreover,the bacterial community structures under the combined stresses of methamidophos and copper were significantly different from those of control and their corresponding single factors.The change of DHA and carbon source substrate utilizing fingerprint patterns based on BIOLOG^(GN)system were two relatively sensitive directors corresponding to the stress presented in this study.Between methamodophos and copper,there happened the significant joint-toxic actions when they were used in combination on DHA and carbon source substrate utilizing fingerprint patterns of soil bacterial communities.The DHA of soil under the combined stresses was lower than that of the control and that under the single factors,and the BIOLOG^(GN) substrate utilizing patterns of soil treated by combinations were distinctively differentiated from the control and their corresponding single factors.From all of above,the methamidophos,copper,especially their combinations had the clearly potential ecotoxicological risks to influence the natural soil microbial ecological system by changing the structure,richness,and the functional characteristics of microbial community.

Responses of soil enzyme and microbial community under co-loading of different microplastics and sulfamethoxazole

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%.

Developments and Prospects of Long-Span High-Speed Railway Bridge Technologies in China

With the rapid developments of the high-speed railway in China, a great number of long-span bridges have been constructed in order to cross rivers and gorges. At present, the longest main span of a constructed high-speed railway bridge is only 630 m. The main span of Hutong Yangtze River Bridge and of Wufengshan Yangtze River Bridge, which are under construction, will be much longer, at 1092 m each. In order to overcome the technical issues that originate from the extremely large dead loading and the relatively small structural stiffness of long-span high-speed railway bridges, many new technologies in bridge construction, design, materials, and so forth have been developed. This paper carefully reviews progress in the construction technologies of multi-function combined bridges in China, including com- bined highway and railway bridges and multi-track railway bridges. Innovations and practices regarding new types of bridge and composite bridge structures, such as bridges with three cable planes and three main trusses, inclined main trusses, slab-truss composite sections, and steel-concrete composite sections, are introduced. In addition, investigations into high-performance materials and integral fabrication and erection techniques for long-span railway bridges are summarized. At the end of the paper, prospects for the future development of long-span high-speed railwav bridges are provided.

Soil particle and moisture-related factors determine landward distribution of bacterial communities in a lateral riverside continuum of the Xilin River Basin

Continuous landscape components along the lateral riverside are affected by both hydrologic connectivity and disconnectivity.In recent years,anthropogenic activities and climate changes have caused wetland shrinkage and land degradation along the lateral riverside of many arid and semiarid regions.Since microorganisms are major drivers of soil biochemical cycling,it is essential to examine soil microbial communities along the lateral landscape continuum to understand their ecosystem functioning and predict future land changes.Here,we collected samples along a lateral riverbed center-riverbed edge-oxbow lake-floodplain-terrace continuum(i.e.,landward distribution)in the Xilin River Basin,Inner Mongolia,China.The floodplain had the highest microbial diversity and heterogeneity,with Bacteroidetes,β-andγ-Proteobacteria being the most abundant taxa.In contrast,the terrace had the lowest microbial diversity and heterogeneity,with Acidobacteria,Actinobacteria,Verrucomicrobia,Gemmatimonadetes,andα-Proteobacteria as the most abundant taxa.Silt particle,salinity,and moisture were the most influential factors for landward variation of bacterial communities along the riverside continuum.Altogether,we demonstrate that dominant bacterial lineages,soil particles,and moisture-related factors are valuable indicators of this continuum,which can be leveraged for the early prediction of drought-induced wetland shrinkage and grassland desertification.

Customary Management System of Irrigation Ponds in Japana Case Study in a Globally Important Agricultural Heritage Systems(GIAHS) Site of Noto Island,Ishikawa Prefecture

Recent research has showed increasing interest at the vital role of irrigation ponds that plays at biodiversity conservation,and provides ecological functions at a wide range.However,many irrigation ponds were abolished due to the economic and societal transformation in the rural.In particular,small-scale ponds were abolished and rebuilt to other public uses based on the consensus building process among the community.At the same time,civil organizations also launched initiatives to conserve irrigation ponds for its ecological significance or landscape scenery.However,study pertinent to the small scale ponds in the rural setting is largely neglected.This research aims at revealing the current situation of the utilization and management of small irrigation ponds using a case study of Noto Island in Ishikawa Prefecture.It was found that irrigation ponds are still under the traditional co-management of rural community.The most important finding in this study is that the traditional management of pond water use largely contributes to mitigate the harvest loss from natural disasters such as drought in the face of extreme climate.However,irrigation ponds are facing the threat of degradation due to the sharp decrease of farm population and the existing large number of part time farmers.Therefore,the small scale irrigation ponds and pertinent management and water use allotment should be revalued for its functions at a wide range from the biological and ecological functions and human knowledge system to mitigate disaster threats.