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Analysis of Tidal Current Energy Potential in the Major Channels of the Bohai Strait Based on Delft3D

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JOURNAL OF OCEAN UNIVERSITY OF CHINA 2024年第4期23卷 859-870页

作者： Ma, Pengcheng Shi, Hongyuan xue, Huaiyuan Li, pingping Sun, Yongkang Ludong Univ China Sch Hydraul Engn Yantai 264025 Peoples R China Ludong Univ China Inst Coastal Res Yantai 264025 Peoples R China Yantai Kekan Marine Technol Co Ltd Yantai 264025 Peoples R China

The utilization and development of tidal current energy can help alleviate the current energy shortage, improve the global ecological environment, and maintain sustainable development. In this study, numerical simulation is carried out on a rectangular grid using Delft3D. The tidal current energy potential of the major channels in the Bohai Strait is further simulated and estimated by comparing the simulated and measured data. Results show that the flow module in Delft3D has good modeling ability for the assessment of tidal current energy potential. The average flow velocity, maximum flow velocity, and energy flow density are consistent. The Laotieshan Channel, located in the northern part of the Bohai Strait, shows a large tidal current energy potential. The maximum flow velocity of this channel can reach 2 m s-1, and the maximum energy flow density can exceed 500 W m-2. The tidal current energy in the Laotieshan Channel is more than 10 times that in other channels. Therefore, this study advocates for the continued exploration and exploitation of the tidal current energy resources in the Laotieshan Channel.

关键词： Delft3D Bohai Strait tidal current energy numerical simulation power density STREAM POWER RESOURCE IMPACTS EXTRACTION FUTURE WAVE

Atmospheric iron deposition in a megacity of northwest China:Solubility,speciation,and deposition fluxes

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Particuology 2024年第7期90卷 383-393页

作者： Xiaotao Yang pingping Liu Zhiwei xue Hao Zhang Xuan Li Hongmei Xu Zhenxing Shen Department of Environmental Science and Engineering Xi'an Jiaotong UniversityXi'anChina State Key Laboratory of Loess and Quaternary National Key R&D of China Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina No.203 Research Institute of Nuclear Industry Xi'an710086China Xi'an Environmental Monitoring Station Xi'an 710054China

Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human *** this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,China,from 2020 to *** spatiotemporal distributions and deposition fluxes of total and water-soluble(ws)Fe as well as the speciation and potential sources of ws-Fe were *** areas had the highest concentrations of total Fe and ws-Fe,which were mainly due to copious emissions of heavy metals during *** total Fe concentrations peaked in spring,primarily due to the substantial input of crustal dust,which also led to the lowest Fe solubility in this *** contrast,the highest levels of ws-Fe occurred during winter due to an increase in biomass *** the water-soluble forms,ws-Fe(II)was dominant and accounted for 74.8%of the total amount of *** dust was the main contributor to total Fe,whereas biomass burning primarily contributed to peak ws-Fe *** average total and ws-Fe deposition fluxes in Xi'an were the highest in spring and lowest in autumn,which were related to the distributions of the dustfall deposition fluxes and their Fe contents during these *** study provided a broader and comprehensive understanding of atmospheric iron deposition in Chinese urban area,which is of positive significance for understanding atmospheric chemistry and global climate change.

关键词： Atmospheric dustfall Iron Speciation distribution Seasonal variation Functional area Sources

Phenotypic plasticity of Artemisia ordosica seedlings in response to different levels of calcium carbonate in soil

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Journal of Arid Land 2019年第1期11卷 58-65页

作者： xue pingping ZHAO xuelai GAO Yubao HE Xingdong College of Life Sciences Nankai University

Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO_3(calcium carbonate) on the phenotypic plasticity of a psammophyte, Artemisia ordosica, an important plant species on sandy lands in arid and semi-arid areas of China, by performing pot experiments under different CaCO_3 contents with a two-factor randomized block design and two orthogonal designs. We analyzed the growth responses(including plant height, root length, shoot-leaf biomass and root biomass) of A. ordosica seedlings to different soil CaCO_3 contents. The results revealed that, with a greater soil CaCO_3 content, A. ordosica seedlings gradually grew more slowly, with their relative growth rates of plant height, root length, shoot-leaf biomass and root biomass all decreasing significantly. Root N/P ratios showed significant negative correlations with the relative growth rates of plant height, shoot-leaf biomass and root length of A. ordosica seedlings; however, the relative growth rate of root length increased significantly with the root P concentration increased, showing a positive correlation. These results demonstrate that soil CaCO_3 reduces the local P availability in soil, which produces a non-adaptive phenotypic plasticity to A. ordosica seedlings. This study should prove useful for planning and promoting the restoration of damaged/degraded vegetation in arid and semi-arid areas of China.

关键词： Artemisia ordosica N/P ratio phenotypic plasticity relative growth rate soil CaCO3 soil P availability arid and semi-arid areas

Seed bank and regeneration dynamics of Emmenopterys henryi population on the western side of Wuyi Mountain,South China

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Journal of Forestry Research 2017年第5期28卷 943-952页

作者： Lianjin Guo pingping xue Mei Li Xinghua Shao College of Life Sciences Shangrao Normal University

Emmenopterys henryi Oliv. (Rubiaceae) is an endangered tree species that is native to China. The wild populations of E. henryi have declined rapidly because of its poor natural regeneration, but the actual regeneration processes are not yet understood. In field tracking surveys and experiments in the Wuyishan Nature Reserve in Southeast China to determine the most important stage that affects the regeneration process, seed bank characteristics, seed germination, and seedling growth dynamics were studied in the typical habitats of E. henryi, Phyllostachys pubescens and broad-leaved forests. Results showed that in both P. pubescens and broad-leaved forests, more than 70% of the E. henryi seeds were distributed in moss and litter layers, and few were found in the soil beneath them. However, seed germination in the soil layer was significantly higher than in the moss and litter layers. Seed density, overall seed quality, and germination rate in the broad-leaved forest were significantly higher than in P. pubescens forest. Seed germination was highest in the microsites around the edge of the crown projection area of E. henryi mother trees. The order of survival rate of the seedlings on different ground surfaces was soil > moss > litter. In both habitats, the average seed density was 24.9 seeds m(-2), and the total germination rate was less than 3.5 parts per thousand. However, seedlings developed from only 1% of the germinated seeds, indicating that the seed germination is the most important stage in the natural regeneration of E. henryi.

关键词： Seed germination Seed viability Seed bank Seedling establishment Seedling survival

Drought resistance of four grasses using pressure-volume curve

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Frontiers in Biology 2007年第4期2卷 425-430页

作者： HE Xingdong CONG Peifang GAO Yubao LU Jianguo WANG Haitao xue pingping ZHANG Xu College of Life Sciences Nankai UniversityTianjin 300071China College of Environmental Science and Engineering Nankai UniversityTianjin 300071China College of Physics Nankai UniversityTianjin 300071China

Pressure-volume curve(PV curve)technique is a major method for studying critical plant water potential and critical tissue water content when plasmolysis takes *** the present study,a mathematical solution method is put forward to obtain parameters based on the PV *** cal-culated results for the parameters of Lolium perenne,Festuca arundinacea,Leymus chinensis and Stipa krylovii indicated that the mathematical solution method is convenient for actual research compared with the graphical *** analysis of the calculations suggested that drought resistance decreased in the following order:***>*** and ***>***.

关键词： pressure-volume curve water potential of plant plasmolysis index of drought resistance

Effects of soil stoichiometry of the CaCO_3/available phosphorus ratio on plant density in Artemisia ordosica communities

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Chinese Science Bulletin 2012年第5期57卷 492-499页

作者： ZHAO xueLai HE XingDong xue pingping ZHANG Ning WU Wei LI Rong CI HuaCong XU JingJing GAO YuBao ZHAO HaLin Colleee of Life Sciences Nankai UniversityTianiin 300071China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

In soil, CaCO3 can reduce the availability of phosphorus in arid and semi-arid regions, thereby influencing plant growth. However, the effects of soil stoichiometry of the CaCO3/available phosphorus ratio (CaCO3/AP ratio) on plant density are unknown. In this study, we examined 4 Artemisia ordosica communities located in arid and semi-arid regions, and performed a pot experiment with an orthogonal design to examine the relationships between the soil CaCO3/AP ratio and plant density. The results showed that the soil stoichiometry of the CaCO3/AP ratio had a greater effect on growth of A. ordosica than either CaCO3 or AP as single factor. The influence of the soil CaCO3/AP ratio on density of A. ordosica was related to the climatic zone and the types and/or amplitudes of increases in the soil CaCO3/AP ratio. When the soil CaCO3/AP ratio was within the same amplitude and was less than 2.5, the A. ordosica density increased in the semi-arid region, whereas the density decreased with increasing soil CaCO3/AP ratios in the arid region. In the semi-arid region, when the soil CaCO3/AP ratio was within the same amplitude and the increase in the soil CaCO3 content was greater than the increase in soil AP, the A. ordosica density increased with increasing soil CaCO3/AP ratios. This means that the relationship between the soil CaCO3/AP ratio and the A. ordosica density remained the same. In the arid region, an increase in the soil CaCO3/AP ratio as a result of increased soil CaCO3 content and decreased soil AP resulted in increased density of A. ordosica. Therefore, the relationship between soil CaCO3/AP ratios and density of A. ordosica was altered by these changes in soil chemistry. Thus, the soil stoichiometry of the CaCO3/AP ratio is an important factor affecting the density of A. ordosica in arid and semi-arid regions.

关键词：化学计量学土壤化学种植密度油蒿群落半干旱地区碳酸钙含量 CaCO3含量比例

Development Status,Challenges and Strategic Reflection of China’s Grain Industry

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Development Status,Challenges and Strategic Reflection of Ch...

线性散焦PT对称波导中饱和非线性孤子传输与控制

作者： pingping xue Institute of Food Economics Nanjing University of Finance ＆ Economics

Under the background of global economic and social integration,the expansion and contraction of world grain supply and demand,the evolution of the world grain trade structure,and fluctuations in international grain prices have a significant impact on the development of China’s grain *** the foundation for the development of China’s grain industry is solid,there are still disadvantages such as grain security concerns,weak grain industry market forces,and insufficient *** order to build a high level grain security system,China should base on the situation of domestic factor resources and grain production and marketing,find out the strategic positioning of the grain industry development,and propose relevant suggestions for the circulation market subject cultivation,scientific and technological innovation,and industrial integration.

关键词： Grain security Grain industry Positioning Countermeasures

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光子学报 2023年第6期52卷 304-312页

作者：武琦王娟芬杜晨锐杨玲珍薛萍萍樊林林太原理工大学光电工程学院太原030600

为了研究线性散焦宇称-时间对称双通道波导中分数阶衍射饱和非线性下孤子的模式以及孤子的传输与控制,通过改进的平方算子迭代法对含有线性势的分数阶饱和非线性薛定谔方程进行数值计算得到孤子模式,傅里叶配置法判断孤子线性稳定性,并... 详细信息

为了研究线性散焦宇称-时间对称双通道波导中分数阶衍射饱和非线性下孤子的模式以及孤子的传输与控制,通过改进的平方算子迭代法对含有线性势的分数阶饱和非线性薛定谔方程进行数值计算得到孤子模式,傅里叶配置法判断孤子线性稳定性,并利用分步傅里叶法模拟仿真孤子的传输。研究结果表明:在散焦饱和非线性中,该宇称-时间对称波导可支持稳定的双峰灰孤子模式。随着饱和非线性系数和传播常数绝对值的增大,双峰灰孤子的背景强度增大,灰度值减小,功率增大。Lévy指数、增益/损耗系数和饱和非线性系数的增加会导致孤子的横向能流密度变化增大,但在波导通道位置处接近于0。在聚焦饱和非线性下,线性散焦宇称-时间对称波导对亮孤子光束具有控制作用。当光束在波导中心输入,孤子以呼吸子的形式长距离传输;在非波导中心输入,光束以初始输入位置为边界振荡传输。随着饱和非线性系数的增大,光束的振荡频率增加,光束宽度变宽,峰值强度减小。宇称-时间对称波导势阱深度的增加会导致光束的振荡频率增加,峰值强度增加。该研究结果可为宇称-时间对称波导对光束的控制提供一定的理论参考。

关键词：非线性光学宇称-时间对称光波导灰孤子光束控制饱和非线性分数阶薛定谔方程

Effects of soil nitrogen:phosphorus ratio on growth rate of Artemisia ordosica seedlings

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Research in Cold and Arid Regions 2010年第4期2卷 328-334页

作者： Wei Wu XingDong He HuaCong Ci Rong Li pingping xue YuBao Gao HaLin Zhao College of Life Sciences Nankai UniversityTianjin 300071China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of ScienceLanzhouGansu 730000China

To address how the ratios of nitrogen and phosphorus (N:P ratios) in soil affect plant growth, we performed a two-factor (soil available N:P ratios and plant density) randomized block pot experiment to examine the relationships between soil N:P ratios, and the N:P ratios and growth rate of Artemisia ordosica seedlings. Under moderate water stress and adequate nutrient status, both soil N:P and plant density influenced the N:P ratios and growth rates of A. ordosica. With the increase of soil N:P ratios, the growth rates of A. ordosica seedlings decreased significantly. With the increase of soil N:P ratios, N:P ratios in A. ordosica seedlings increased significantly. While the nitrogen concentrations in the plant increased slightly, the phosphorus concentrations significantly decreased. With the increase of plant density, the shoot N:P ratios and growth rates significantly decreased, which resulted from soil N:P ratios. Thus, soil N:P ratios influenced the N:P ratios in A. ordosica seedlings, and hence, influenced its growth. Our results suggest that, under adequate nutrient environment, soil N:P ratios can be a limiting factor for plant growth.

关键词： Artemisia ordosica soil N:P ratio plant N:P ratio plant growth rate nutrient limitation