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Changes in Lake Ice Cover on the Morskie Oko Lake in Poland(1971-2007)

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Advances in Climate Change Research 2010年第2期1卷 71-75页

作者： Adam Choiński Leszek Kolendowicz Joanna Pociask-Karteczka Leszek Sobkowiak institute of Physical geography and environmental Planning institute of geography and Spatial Management

On the basis of data from the period 1971-2007, and by applying trend analysis, a study on formation, disappearance and duration of lake ice cover on the Morskie Oko Lake in the Tatra Mountains in southern Poland was carried out. The results show decreasing trends in the maximum thickness of winter lake ice cover and in duration of lake ice phenomena, while air temperature recorded at the same period at the foot of the Tatra Mountains shows increasing trend. There are strong relationships between the course of lake ice phenomena and air temperature.

关键词： lake ice cover thickness duration of lake ice phenomena air temperature

Socioeconomic drivers of the human microbiome footprint in global sewage

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Frontiers of environmental science & Engineering 2024年第10期18卷 155-164页

作者： Minglei Ren Shaojuan Du Jianjun Wang Key Laboratory of Lake and Watershed science for Water Security Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Lake science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Nanjing institute of environmental sciences Ministry of Ecology and EnvironmentNanjing 210042China

The human microbiome leaves a legacy in sewage ecosystems,also referred to as the human sewage microbiomes(HSM),and could cause potential risk to human health and ecosystem ***,these host-associated communities remain understudied,especially at a global scale,regarding microbial diversity,community composition and the underlying ***,we built a metagenomic read mapping-based framework to estimate HSM abundance in 243 sewage samples from 60 countries across seven *** approach revealed that 95.03% of human microbiome species were identified from global sewage,demonstrating the potential of sewage as a lens to explore these human-associated microbes while bypassing the limitations of human privacy *** identified significant biogeographic patterns for the HSM community,with species richness increasing toward high latitudes and composition showing a distance-decay relationship at a global ***,the HSM communities were mainly clustered by continent,with those from Europe and North America being separated from Asia and ***,global HSM diversity was shown to be shaped by both climate and socioeconomic ***,the average annual temperature was identified as the most important factor for species richness(33.18%),whereas economic variables such as country export in goods and services contributed the most to the variation in community composition(27.53%).Economic and other socioeconomic variables,such as education,were demonstrated to have direct effects on the HSM,as indicated by structural equation *** study provides the global biogeography of human sewage microbiomes and highlights the economy as an important socioeconomic factor driving host-associated community composition.

关键词： Human sewage microbiome Biogeography Socioeconomic factors Climate factors

Lattice Boltzmann model for shallow water in curvilinear coordinate grid

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Journal of Hydrodynamics 2017年第2期29卷 251-260页

作者：赵庄明黄平李少钿 South China institute of environmental sciences the Ministry of Environmental Protection of PRC Department of environmental science School of Environmental Science and EngineeringSun Yat-sen University

In this study, a multi-relaxation time lattice Boltzmann model for shallow water in a curvilinear coordinate grid is developed using the generalized form of the interpolation supplemented lattice Boltzmann method. The Taylor-Colette flow tests show that the proposed model enjoys a second order accuracy in space. The proposed model is applied to three types of meandering channels with 180°, 90°and 60° consecutive bends. The numerical results demonstrate that the simulated results agree well with previous computational and experimental data. In addition, the model can achieve the acceptable accuracy in terms of the water depth and the depth-averaged velocities for shallow water flows in curved and meandering channels over a wide range of bend angles.

关键词： Curvilinear coordinate lattice Boltzmann method meandering flow multi-relaxation-time model shallow water

Evolvement Characteristics of Population and Economic Gravity Centers in Tarim River Basin,Uygur Autonomous Region of Xinjiang,China

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Chinese Geographical science 2013年第6期23卷 765-772页

作者： WANG Yang CHEN Yaning LI Zhi College of Resources and environmental science Xinjiang University State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences

Using the data at the county levcl and the regional gravity center model, we calculated six key socio-economic gravity centers, namely population, GDP, output values of primary, secondary and tertiary industries, and arable land area in the Tarim River Basin for each year from 1980 to 2009. We inspected the spatial dynamics of these centers and found that the gravity centers of population and economy evolved simultaneously. The disproportional growth between the population and the economy is also analyzed. The results show that： 1） The gravity centers of the GDR the output values of the main three industries and arable land area show migration trending from southwest to northeast, while the population gravity center shows an excessive growth in the southwest during the same time period. The migration amplitude of the GDP and output values of primary industry, secondary industry, tertiary industry are measurably higher than that of the population. 2） The population gravity center has a negative correlation with the gravity centers of secondary and tertiary industries output values in both longitudinal and latitudinal directions, and a positive correlation with that of primary industry output value in the longitudinal direction. Based on the analysis of correlation coefficient and offset distance, the imbalance between the population and the economy has increased since the 1980s, with regional economic differences now exceeding the international cordon.

关键词： regional gravity center model population gravity center economic gravity center Tarim River Basin

Interdecadal variation of drought patterns and associated influencing factors in the north-south transitional zone of China

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Journal of Geographical sciences 2024年第7期34卷 1253-1279页

作者： DONG Qingdong ZHU Lianqi DUAN Zheng WANG Liyuan CHEN Chaonan LI Yanhong ZHU Wenbo GURUNG Sher Bahadur The College of geography and environmental science Henan UniversityKaifengHenan475004China Department of Physical geography and Ecosystem science Lund UniversityLundS-22362Sweden Central Department of geography Tribhuvan UniversityKathmandu44600Nepal

In the context of global warming,escalating water cycles have led to a surge in drought frequency and ***,multidecadal fluctuations in drought and their multifaceted influencing factors remain inadequately *** study examined the multidecadal changes in drought characteristics(frequency,duration,and severity)and their geographical focal points within China's north-south transitional zone,the Qinling-Daba Mountains(QDM),from 1960 to 2017 using the Standardized Precipitation Evapotranspiration Index(SPEI).In addition,a suite of eight scenarios,correlation analysis,and wavelet coherence were used to identify the meteorological and circulation factors that influenced drought *** results indicate the following:(1)From 1960 to 2017,the QDM experienced significant interdecadal variations in drought frequency,duration,and severity,the climate was relatively humid before the 1990s,but drought intensified ***,the 1990s marked the period of the longest drought duration and greatest severity,while the years spanning 2010 to 2017 experienced the highest frequency of drought events.(2)Spatially,the Qinling Mountains,particularly the western Qinling Mountain,exhibited higher drought frequency,duration,and severity than the Daba *** disparity can be attributed to higher rates of temperature increase and precipitation decrease in the western Qinling Mountain.(3)Interdecadal variations in droughts in the QDM were directly influenced by the synergistic effects of interdecadal fluctuations in air temperature and *** factors modulate temperature and precipitation through phase transitions,thereby affecting drought dynamics in the *** Atlantic Multidecadal Oscillation emerges as the primary circulation factors influencing temperature changes,with a mid-1990s shift to a positive phase favoring *** East Asian Summer Monsoon and El Ni?o-Southern Oscillation are the main circulation factors a

关键词： drought standardized precipitation evapotranspiration index multidecadal shift transitional zone Qinling-Daba Mountains

Regional Difference in Social Capital and Its Impact on Regional Economic Growth in China

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Chinese Geographical science 2010年第5期20卷 442-449页

作者： PAN Fenghua HE Canfei Department of Urban and Economic geography College of Urban and Environmental Science Peking University Beijing 100871 China

Social capital has played an increasingly important role in regional *** is a country with high stocks of social *** several different indicators of social capital,this study tries to research the regional disparities in social capital and the influence of social capital on economic growth of China in *** social capital with indicators of associations,charities and blood donation rates,this study finds significant regional disparities in social capital at provincial level in *** indicators for social capital are highly correlated with regional economic *** analysis shows that social capital has a significant and positive effect on a long-term provincial economic *** relationship exists after controlling policy,macro location factors,and per capita GDP in the initial *** empirical findings indicate that institutions,culture and social relations are critical for regional development in ***,the creation and support of social capital should be paid more attention to when making regional policy.

关键词： social capital trust economic growth transaction cost

Prediction of effluent concentration in a wastewater treatment plant using machine learning models

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Journal of environmental sciences 2015年第6期27卷 90-101页

作者： Hong Guo Kwanho Jeong Jiyeon Lim Jeongwon Jo Young Mo Kim Jong-pyo Park Joon Ha Kim Kyung Hwa Cho School of environmental science and Engineering Gwangju Institute of Science and Technology (GIST) School of Urban and environmental Engineering Ulsan National Institute of Science and Technology HECOREA. INC

Of growing amount of food waste, the integrated food waste and waste water treatment was regarded as one of the efficient modeling method. However, the load of food waste to the conventional waste treatment process might lead to the high concentration of total nitrogen（T-N） impact on the effluent water quality. The objective of this study is to establish two machine learning models-artificial neural networks（ANNs） and support vector machines（SVMs）, in order to predict 1-day interval T-N concentration of effluent from a wastewater treatment plant in Ulsan, Korea. Daily water quality data and meteorological data were used and the performance of both models was evaluated in terms of the coefficient of determination（R^2）, Nash-Sutcliff efficiency（NSE）, relative efficiency criteria（d rel）. Additionally, Latin-Hypercube one-factor-at-a-time（LH-OAT） and a pattern search algorithm were applied to sensitivity analysis and model parameter optimization, respectively. Results showed that both models could be effectively applied to the 1-day interval prediction of T-N concentration of effluent. SVM model showed a higher prediction accuracy in the training stage and similar result in the validation ***, the sensitivity analysis demonstrated that the ANN model was a superior model for 1-day interval T-N concentration prediction in terms of the cause-and-effect relationship between T-N concentration and modeling input values to integrated food waste and waste water treatment. This study suggested the efficient and robust nonlinear time-series modeling method for an early prediction of the water quality of integrated food waste and waste water treatment process.

关键词： Artificial neural network Support vector machine Effluent concentration Prediction accuracy Sensitivity analysis

The Glacier Area Changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate Change

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Journal of Mountain science 2011年第6期8卷 882-893页

作者： WANG Liping XIE Zichu WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui The College of Resources and environmental science Hunan Normal University Changsha China Cold and Arid Regions environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China Department of geography Hunan University of Science and Technology Xiangtan China

Glacier area changes in the Qangtang Plateau are analyzed during 1970-2000 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid *** results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2000 in the whole Qangtang ***,the glaciers seemed still more stable in the study area than in most areas of western *** estimate that glacier retreat was likely due to air temperature warming during 1970-2000 in the Qangtang ***,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.

关键词： The Qangtang Plateau Glacier change Multi-temporal Climate change Functional model ofglacier system Simulation

Research on the conversion relationships between the river and groundwater in the Yellow River drainage area

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science China(Technological sciences) 2004年第z1期47卷 25-41页

作者： WANG Wenke KONG Jinling DUAN Lei WANG Yanlin MA Xiongde environmental science and Engineering institute Chang'an University Xi'an 710054 China Environmental Science and Engineering Institute Chang'an University Xi'an 710054 China Environmental Science and Engineering Institute Chang'an University Xi'an 710054 China Environmental Science and Engineering Institute Chang'an University Xi'an 710054 China Environmental Science and Engineering Institute Chang'an University Xi'an 710054 China

Conversion relationships between the river and groundwater in the Yellow River drainage area are studied in this paper based on the geologic and physiognomy conditions and the data of the groundwater regime, isotope, groundwater flow field and field survey. Then eight recharge and discharge modes on the relationships are put forward and the hydraulic characteristics of the modes are analysed, which provides a scientific basis for quantitatively simulating and assessing the conversion relationships, maintenance mechanism of the Yellow River and the regeneration ability of the groundwater in the area.

关键词： conversion relationship between river and groundwater, recharge and discharge mode, the Yellow River drainage area.