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Growth and nutrient accumulation of Phragmites australis in relation to water level variation and nutrient loadings in a shallow lake

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Journal of Environmental Sciences 2013年第1期25卷 16-25页

作者： Ying Zhao Xinghui Xia zhifeng yang State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University

Shallow lake eutrophication is a global environmental issue. This study investigated the effects of water level variation and nutrient loadings on the growth and nutrient accumulation of Phragmites australis （reed） by field samplings in Baiyangdian Lake, the largest shallow lake of northern China. The field samplings were conducted in two sites of different nutrient loadings during the whole growth period of reeds, and three types of zones with different water depths were chosen for each site, including the terrestrial zone with water level below the ground, the ecotone zone with the water level varying from belowground to aboveground, and the submerged zone with water level above the ground. The result showed that reed growth was more limited by water level variation than nutrient loadings. The average stem lengths and diameters in terrestrial zones were about 26.3%-27.5% and 7.2%-12.0% higher than those in submerged zones, respectively. Similarly, the terrestrial status increased the aboveground biomass of reeds by 36.6%-51.8% compared with the submerged status. Both the nutrient concentrations and storages in the aboveground reeds were mainly influenced by the nutrient loadings in surface water and sediment rather than the water level variation of the reed growth environment, and the nutrient storages reached their maxima in late August or early September. It was observed that the maximum nitrogen storage occurred in the terrestrial zone with higher nutrient loadings, with the value of 74.5 g/m2. This study suggested that water level variation and nutrient loadings should be considered when using reeds to control and remediate eutrophication of shallow lakes.

关键词： water level variation nutrient loadings Phragmites australis reed growth nutrient accumulation

Effects of the Lithologic Character of Manufactured Sand on Properties of Concrete

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Journal of Wuhan University of Technology(Materials Science) 2014年第6期29卷 1213-1218页

作者：王稷良 yang zhifeng LIU Yihan Research Institute of Highway Ministry of Communication

Six representative parent rocks of sand, including limestone, quartzite, gneisses, granite, Basalt and Marble were selected to conduct a systematical research on the effects of various lithologies of manufactured sand on the workability, mechanism properties, volume stability and durability of manufacturedsand concrete. The experimental results show that the strength of manufactured-sand concrete is slightly higher than that of natural-sand concrete. Furthermore, substituting 15% cement of the concrete mixture with equal quantity of the six different lithology stone powder respectively, the data indicated that they can improve the concrete’s workability, postpone the plastic cracking time, enhance the anti-cracking grade, and have no obvious effect on the properties of antifreeze and sulfate attack resistance but reduce the capability to resist chloride ion penetration. Moreover, the differences in concrete’s workability, mechanism properties, volume stability and durability caused by various lithologies of manufactured sand and stone powder were not significant and the influence of lithology variety on the macro properties of concrete could be neglected eventually.

关键词： manufactured sand lithologic character workability volume stability durability

Soil Organic Carbon Changes in City Areas of China Over the Past Three Decades:Implications for Achieving Carbon Neutrality

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Engineering 2023年第9期28卷 11-15页

作者： Zhenrui Zhang Xinghui Xia zhifeng yang Key Laboratory of Water and Sediment Sciences of Ministry of Education&State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China

The substantial amount of greenhouse gas emissions from anthropogenic activities has caused the global mean surface temperature to increase by 0.99℃since the industrial revolution[1].China is committed to achieving carbon neutrality by 2060 in response to climate change[2].Soil stores approximately 2344–3000 Pg(1015 g)of carbon at depths of 0–100 cm in terrestrial ecosystems,an amount approximately equivalent to twice the amount in the atmospheric carbon pool and three times that in the terrestrial biomass;therefore,even a small change in soil carbon stocks will exert significant impacts on atmospheric CO_(2)concentrations[3].

关键词： stores terrestrial Carbon

A system dynamics urban water management model for Macao, China

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Journal of Environmental Sciences 2016年第12期28卷 117-126页

作者： Tong Wei Inchio Lou zhifeng yang Yingxia Li State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China. Department of Civil and Environmental Engineering University of Macao Macao 999078 China

Urban water resources have been facing significant pressure from population growth, urbanization, and climate change. A system dynamics urban water management model was proposed to simulate the dynamic interactions between urban water demands and society, economy, climate, and water conservation. The residents＇ water conseration willingness was incorporated in the model and water-saving effects were quantified. The simulation results for Macao showed that population size was the main driving force for urban water demand. The change of temperature and precipitation has obvious effects on the landscape water demand. The water demand output is sensitive to the change in population, per capita demand, and temperature. Increased precipitation will reduce urban water demand and increased economic growth will increase water demand. By implementing integrated water conservation measures and imoroved water conservation willinmaess, water demand could be reduced bv 17.5%.

关键词： Macao System dynamics Water conservation willingness Water demand

Microbial diversity of sediments from an inactive hydrothermal vent field,Southwest Indian Ridge

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Marine Life Science & Technology 2020年第1期2卷 73-86页

作者： zhifeng yang Xiang Xiao Yu Zhang School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Microbial Metabolism and School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

The Southwest Indian Ridge,which is the slowest-spreading of the main ridges,separates the African and Antarctic *** slow expanding rate is associated with less density of hydrothermal vent fields,shorter longevity of hydrothermal activity,cold mantle temperatures and thick ***,the microbial communities adapting to such specific characteristics of this area have remained largely *** study the microbial diversity at the Southwest Indian Ridge,we sampled three sediment cores in a newly found inactive vent field,the Tianzuo field,and used high-throughput sequencing of 16S rRNA genes to reveal the microbial *** communities of three sampling sites were very similar at the surface,and underwent a gradient change along ***,namely Alteromonadaceae,Nitrosococcus and the JTB255 marine benthic group,were the most dominant bacterial *** Group I was the dominant archaeal taxon in our *** addition,microbial populations capable of ammonia oxidation,nitrite oxidation,sulfur oxidation and manganese oxidation were detected to be the main *** enrichment of sulfur-oxidizing and manganese-oxidizing bacteria was observed in deep *** compared with other vent fields along different ocean ridges,the Tianzuo field showed distinct composition in both archaeal and bacterial *** results provide the first view of microbial communities of the Tianzuo field at the Southwest Indian Ridge,and give a better understanding of metabolic potential possessed by the microbial populations.

关键词： Hydrothermal Microbial diversity High-throughput sequencing Deep-sea sediments Ultraslow-spreading ridge

The frontier evolution and emerging trends of hydrological connectivity in river systems:a scientometric review

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Frontiers of Earth Science 2021年第1期15卷 81-93页

作者： Bowen LI zhifeng yang Yanpeng CAI Bo LI Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China

With the intensification of climate change and human activities,the watershed ecosystem is seriously fragmented,which leads to the obstruction of hydrological connectivity,and further causes the degradation of the *** the value of wetlands continues to be exploited,hydrological connectivity becomes increasingly *** this paper,the characteristics and development of hydrological connectivity research from 1998 to 2018 were analyzed through the scientometric analysis based on Web of Science ***,an analytical software for scientific measurement,is used to visualize the results of the *** analysis results of co-occurrence,co-operative and co-cited network indicate that the hydrological connectivity is a multidisciplinary field which involves the Environment Science and Ecology,Water Resources,Environmental Sciences,Geology and *** to Keyword cooccurrence analysis,ecosystem,floodplain,dynamics,climate change and management are the main research hotspots in each *** addition,the co-cited analysis of references shows that“amphibians”is the largest cluster of hydrological connectivity,and the“channel network”is the most important research *** is worth noting that the“GIWS”(Geographically Isolated Wetlands)is the latest research topic and may be a major research direction in the future.

关键词： hydrological connectivity citespace ecosystem geographically isolated wetlands

Evaluation of economic loss from energy-related environmental pollution： a case study of Beijing

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Frontiers of Earth Science 2013年第3期7卷 320-330页

作者： Chen CHEN Meirong SU Gengyuan LIU zhifeng yang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

With the growth of energy consumption, energy-related environmental pollution has become increasingly serious, which in turn causes enormous economic loss because of public health damage, corrosion of materials, crop yield reduction, and other factors. Evaluating economic loss caused by energy-related environmental pollution can contribute to decision making in energy management. A framework for evaluating economic loss from environmental pollution produced during energy production, transportation, and consumption is proposed in this paper. Regarding SO2, PMlo, and solid waste as the main pollutants, economic losses from health damage, materials corrosion, crop yield reduction, and solid waste pollution are estimated based on multiple concentration-response relationships and dos^response functions. The proposed framework and evaluation methods are applied to Beijing, China. It is evident that total economic loss attributable to energy-related environ-mental pollution fluctuated during 2000-2011 but had a general growth trend, with the highest value reaching 2.3× 108 CNY （China Yuan） in 2006. Economic loss caused by health damage contributes most to the total loss among the four measured damage types. The total economic loss strongly correlates with the amount of energy consumption, especially for oil and electricity. Our evaluation framework and methods can be used widely to measure the potential impact of environmental pollution in the energy lifecycle.

关键词： economic loss environmental pollution health damage energy lifecycle Beijing

An improved ET control method to determine the water-saving potential for farmland in Baiyangdian Watershed, China

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Frontiers of Earth Science 2013年第2期7卷 151-158页

作者： Aiping PANG Chuihui LI Tao SUN zhifeng yang State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China Key Laboratory for Water and Sediment Sciences (Ministry of Education) School of Environment Beijing Normal University Beijing 100875 China

Resource-based water-saving potential has been recognized as the reduction of evapotranspiration and water loss of inefficient irrigation systems. In this paper, an improved evapotranspiration control model is applied to calculate resource-based water-saving potential, considering the influences of effective rainfall （uncontrolled evapotranspiration） and irrigated water （controlled evapotranspiration）. Farmland in Baiyangdian Watershed, a highly productive area in northern China, is analyzed to determine the water-saving potential of irrigation processes. The water-saving potential was zero, 163.90 × 10^6m3, and 318.24 × 10^6m3 in wet, normal, and dry years, respectively, and was greater in years with less rainfall. Under the combined effect of rainfall, crop water consumption, and crop water requirements, the water-saving potential showed obvious temporal and spatial variations. July and August comprised almost 98.6% of the annual potential. In the northeast and southwest corner of the study area, potential approached zero. The potential was 1.53 times greater in the north-central than in the south-central area. The model can furnish the appropriate timing and region to water managers for implementing water-saving strategies.

关键词： resources-based water-saving potential evapotranspiration improved evapotranspiration control model Baiyangdian Watershed

An optimal hydropower contract load determination method considering both human and riverine ecosystem needs

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Frontiers of Earth Science 2015年第3期9卷 546-554页

作者： Xin'an YIN zhifeng yang Cailing LIU Yanwei ZHAO State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

In this research, a new method is developed to determine the optimal contract load for a hydropower reservoir, which is achieved by incorporating environ- mental flows into the determination process to increase hydropower revenues, while mitigating the negative impacts ofhydropower generation on riverine ecosystems. In this method, the degree of na^ral flow regime alteration is adopted as a constraint of hydropower generation to protect riverine ecosystems, and the maximization of mean annual revenue is set as the optimization objective. The contract load in each month and the associated reservoir operating parameters were simultaneously optimized by a genetic algorithm. The proposed method was applied to China＇s Wangkuai Reservoir to test its effectiveness. The new method offers two advantages over traditional studies. First, it takes into account both the economic benefits and the ecological needs of riverine systems, rather than only the economic benefits, as in previous methods. Second, although many measures have been established to mitigate the negative ecological impacts ofhydropower generation, few have been applied to the hydropower planning stage. Thus, since the contract load is an important planning parameter for hydropower generation, influencing both economic benefits and riverine ecosystem protection, this new method could provide guidelines for the establishment of river protection measures at the hydropower planning stage.

关键词： hydropower electricity supply load reservoiroperation river protection