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geomorphologic patterns of dune networks in the Tengger Desert,China

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Journal of Arid Land 2016年第5期8卷 660-669页

作者： WEN Qing DONG Zhibao Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Department of geography Shaanxi Normal University

Dune networks are widely distributed in the world＇s deserts,which include primary ridges and secondary ***,they have not been sufficiently studied in a systematic manner and their origins and spatial and morphological characteristics remain *** provide information on the geomorphology of dune networks,we analyze the software geomorphologic patterns of the dune networks in China＇s Tengger Desert using matrix and lab.ratory to process remote-sensing *** on analysis of image features and their layout in a topographic map,we identify two types of dune networks （square and rectangular dune networks） with different size and morphological structures in the Tengger *** important geomorphic pattern parameters,ridge length,spacing,orientation and defect density,are *** length of primary ridges of dune networks decreases from northwest of the desert to the southeast,resulting an increasing spacing and a transition from rectangular dune networks to square dune *** regime and sediment supply are responsible for the variation in pattern *** use the spacing and defect density data to estimate the construction time of dune networks and found that the dune networks in the Tengger Desert formed since about 1.3 ka BP.

关键词： aeolian geomorphology dune networks geomorphological parameters geomorphic pattern analysis Tengger Desert

The Climatic Fluctuation and Important Events of Holocene Megathermal in China

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Science China Chemistry 1994年第3期37卷 353-365页

作者：施雅风孔昭宸王苏民唐领余王富葆姚檀栋赵希涛张丕远施少华 Lanzhou institute of Gladology and Geocryology Academia Sinica Lanzhou 730000 PRC institute of Botany Academia Sinica Beijing 100044. Lake Sediment and Environment lab Nanjing Institute of Geography and Limnology Academia SinicaNanjing 210008. Nanjing institute of Geology and Paleontology Academia Sinica Nanjing 210008. Department of Geology and Ocean Sciences Nanjing University Nanjing 210008. institute of Geology Academia Sinica Beijing 100029. institute of geography Academia Sinica Beijing 100101.

Data from various sources including the ice core, inland lakes , paleosols in loess and eolian sands, sea level fluctuations, paleozoological, archeological evidences especially palynology and bontanical studies of China are reviewed . Holocene Megathermal mainly appeared during 8. 5-3 ka BP and lasted for 5. 5 ka. There were several strong climatic fluctuations and cooling events during this period, e. g. it was an unstable temperature fluctuation phase during 8. 5-7. 2 ka BP and was accompanied with the increase of the precipitation as well as the northward and westward migration of the vegetation zone ; the rapid development of Neolithic Culture happened in this phase. It was a stable warm and wet phase from 7. 2 to 6 ka BP, i. e. Megathermal Maximum, when monsoon was rainfall almost throughout China, plants were unprecedentedly flourished, and the Yangshao Culture reached its climax. It is characterized by strong climatic fluctuation and adverse environment during 6-5 ka BP and the impact of strong cooling events on the culture development. After 5 ka BP, the climate and environment were better than those of the former phase, and there was a sharp increase on the number of archaeological sites. Around 4 ka BP, the climate deteriorated and catastrophic flood happened ; from then to 3 ka BP, the climate was still warm and humid.

关键词： Holocene Megathermal climatic fluctuation environment.

Degradation of a protected mountain area by tourist traffic:case study of the Tatra National Park,Poland

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Journal of Mountain Science 2021年第10期18卷 2503-2519页

作者： Joanna FIDELUS-ORZECHOWSKA Elzbieta GORCZYCA Marcin BUKOWSKI Kazimierz KRZEMIEN institute of geography Pedagogical University of KrakowPodchorqzych 230-084 KrakowPoland institute of geography and Spatial Management Jagiellonian UniversityGronostajowa 730-387 KrakowPoland Tatra National Park Kuznice 134-500 ZakopanePoland

Mountain protected areas are characterized by high biodiversity,which makes it a great challenge for managers to maintain a balance between their use and the stability of natural *** that balance is particularly difficult in areas with high tourism *** expected volume of tourist traffic should be considered at the planning stage of the tourist infrastructure development *** capacity of tourist infrastructure can lead to environmental degradation,which is hard,or at times impossible,to *** our research,we identified patterns of tourist footpath and road functioning in an environmentally protected area with high volumes of tourist *** from geomorphologic mapping was analyzed in order to identify tourist footpath and road structures in the Tatra National Park(TNP).Fieldwork was conducted in several stages between 1995 and *** from the years 1977,2009,2017 and 2019 were used to identify and compare degraded zones along selected tourist *** zones were defined as areas surrounding a footpath or tourist road with a mean width larger than or equal to 10 meters,with heavily damaged or completely removed vegetation and exposed,weathered cover,where geomorphic processes that would not take place under normal conditions are readily *** examined tourist footpaths and roads vary in terms of their morphometric *** has shown important differences between mean and maximum footpath width as well as maximum incision depth for the forest zone versus the subalpine and alpine zones.A lack of differences in these parameters was noted between the alpine and subalpine *** has shown that an increase in the surface area of degraded zones found adjacent to tourist footpaths occurred in all the studied geo-ecological zones in the study ***,the largest increase occurred atop wide ridgelines found in the alpine *** zones may be an indication of exce

关键词： Tourist traffic Degraded zones Mountain area Morphogenetic processes Carrying capacity

Quantifying cold front induced water transport of a bay with in situ observations using manned and unmanned boats

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Acta Oceanologica Sinica 2018年第11期37卷 1-7页

作者： WEEKS Eddie ROBINSON Mark E LI Chunyan Coastal Studies institute Department of Oceanography and Coastal Sciences Louisiana State University Department of geography and Anthropology Louisiana State University

The generation of high-resolution data is increasingly important in understanding the complexities of coastal ocean and developing sound management strategies, especially in view of the long-term impact of severe weather systems. The impact of severe weather systems, when integrated over time, can be significant when compared with tidal oscillations. This paper presents a study of water transport out of Vermilion Bay in response to a short, intense event associated with a passing atmospheric cold front, and reports the application of an Acoustic Doppler Current Profiler （ADCP） mounted on an Automated Surface Craft （ASC）, known as the auto-boat or unmanned boat, developed in our lab.at the Louisiana State University, to generate high resolution data accurately at a fraction of the cost of a manned boat. In our study, we used a manned boat and an unmanned boat, each for over 24 h to cover an entire diurnal tidal cycle, to measure flow velocity profiles to calculate the total transport. A stationary ADCP was deployed in the Southwest Pass of the Vermilion Bay from May 2009 to April 2012, providing data almost continuously （with only one major gap）, with a 717-day record of water transport between the northern Gulf of Mexico and Vermilion Bay, and demonstrates the importance of the pass in water transport.

关键词： cold fronts unmanned boat Vermillion Bay Acoustic Doppler Current Profiler surveys regression on transport

Preliminary study on assessment of nutrient transport in the Taihu Basin based on SWAT modeling

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Science China Earth Sciences 2006年第Z1期49卷 135-145页

作者： LAI Geying, YU Ge & GUI Feng Nanjing institute of geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China The Graduate School of the Chinese Academy of Sciences, Beijing 100039, China Key lab.of Poyang Lake Ecological Environment and Resource Development, Jiangxi Normal University, Nanchang 330027, China Nanjing institute of geography & Limnology Chinese Academy of Sciences Nanjing China The Graduate School of the Chinese Academy of Sciences Beijing China Key lab.of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China

With the Taihu Basin as a study area, using the spatially distributed and mechanism-based SWAT model, preliminary simulations of nutrient transport in the Taihu Basin during the period of 1995～2002 has been carried out. The topography, soil, meteorology and land use with industrial point pollution discharge, the loss of agricultural fertilizers, urban sewerage, and livestock drainages were all considered in the boundary conditions of the simulations. The model was calibrated and validated against water quality monitoring data from 2001 to 2002. The results show that the annual total productions of nitrogen (TN) and phosphorus (TP) into Lake Taihu are 40000t and 2000t respectively. Nutrient from the Huxi Region is a major resource for Lake Taihu. The non-point source (surface source) pollution is the main form of catchment sources of nutrients into Lake Taihu,occupied TN 53% and TP 56% respectively. TN and TP nutrients from industrial point pollution discharge are 30% and 16%, and sewerage in both forms of point source and non-point source are TN 31% and TP 47%. Both the loss of agricultural fertilizers and livestock drainages from the catchment should be paid more attention as an important nutrient source. The results also show that SWAT is an effective model for the simulation of temporally and spatially nutrient changes and for the assessment of the trends in a catchment scale.

关键词： Taihu Basin, nutrients, catchment resource inputs, SWAT model, simulation.

A system dynamics approach for water resources policy analysis in arid land:a model for Manas River Basin

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Journal of Arid Land 2013年第1期5卷 118-131页

作者： ShanShan DAI LanHai LI HongGang XU XiangLiang PAN XueMei LI Faculty of Hospitality and Tourism Management Macao University of Science and Technology Macao 999078 China State Key lab.ratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Xinjiang Key lab.of Water Cycle and Utilization in Arid Zone Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China School of Tourism Management Sun Yat-sen University Guangzhou 510275 China

The Manas River Basin in Xinjiang Uygur autonomous region, similar to other arid regions, is facing water constraints which challenge decision-makers as to how to rationally allocate the availab.e water resources to meet the demands from industries and natural ecosystems. Policies which integrate the supply and demand are needed to address the water stress issues. An object-oriented system dynamics model was developed to capture the interrelationships between water availab.lity and increasing water demands from the growth of industries, agri- cultural production and the population through modeling the decision-making process of the water exploration ex- plicitly, in which water stress is used as a major indicator. The model is composed of four sectors： 1 ） natural surface and groundwater resources; 2） water demand; 3） the water exploitation process, including the decision to build reservoirs, canals and pumps; 4） water stress to which political and social systems respond through increasing the supply, limiting the growth or improving the water use efficiency. The model was calibrated using data from 1949 to 2009 for population growth, irrigated land area, industry output, perceived water stress, groundwater resources availab.lity and the drying-out process of Manas River; and simulations were carried out from 2010 to 2050 on an annual time step. The comparison of results from calibration and observation showed that the model corresponds to observed behavior, and the simulated values fit the observed data and trends accurately. Sensitivity analysis showed that the model is robust to changes in model parameters related to population growth, land reclamation, pumping capacity and capital contribution to industry development capacity. Six scenarios were designed to inves- tigate the effectiveness of policy options in the area of reservoir relocation, urban water recycling, water demand control and groundwater pumping control. The simulation runs demonstrated that the te

关键词： water resources management sustainable development system dynamics modeling water stress arid river basin

Spatial and temporal trends of climate change in Xinjiang, China

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Journal of Geographical Sciences 2011年第6期21卷 1007-1018页

作者： LI Qihu CHEN Yaning SHEN Yanjun LI Xingong XU Jianhua Key lab.of GIScience of the Ministry of Education East China Normal University Shanghai 200062 China State Key lab.ratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography CAS Urumqi 830002 China Key lab.ratory of Agricultural Water Resources Center for Agricultural Resources Research CAS Shijiazhuang 050021 China Department of geography University of Kansas Lawrence KS 66045 USA

Temperature and precipitation time series datasets from 1961 to 2005 at 65 meteorological stations were used to reveal the spatial and temporal trends of climate change in Xinjiang, China. Annual and seasonal mean air temperature and total precipitation were analyzed using Mann-Kendall （MK） test, inverse distance weighted （IDW） interpolation, and R/S methods. The results indicate that：（1） both temperature and precipitation increased in the past 45 years, but the increase in temperature is more obvious than that of precipitation; （2） for temperature increase, the higher the latitude and the higher the elevation the faster the increase, though the latitude has greater influence on the increase. Northern Xinjiang shows a faster warming than southern Xinjiang, especially in summer; （3） increase of precipitation occurs mainly in winter in northern Xinjiang and in summer in southern Xinjiang. lli, which has the most precipitation in Xinjiang, shows a weak increase of precipitation; （4） although both temperature and precipitation increased in general, the increase is different inside Xinjiang; （5） Hurst index （H） analysis indicates that climate change will continue the current trends.

关键词： climate change MK test Xinjiang IDW R/S

Grain-size cycles in Salawusu River valley since 150 ka BP

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Journal of Geographical Sciences 2001年第4期11卷 81-92页

作者： ZHANG Yu-hong LI Bao-sheng JIN He-ling David Dian ZHANG YAN Mun-cun ZHU Yi-zhi YAO Chun-xia Dept. of geography South China Normal University State Key lab.of Loess and Quaternary Geology Institute of Earth Environment CAS Cold and Arid Regions Environmental and Engineering Research institute CAS Dept. of geography and Geology Hong Kong University Dept. of Hydraulic Engineering Tsinghua University State Key lab.of Loess and Quaternary Geology Institute of Earth Environment CAS Dept. of geography South China Normal University

The palaeo-mobile dune sands and fluvio-lacustrine facies with palaeosols in Milanggouwan stratigraphic section of the Salawusu River valley situated at the southeast of the Mu Us Desert experienced abundant remarkable alternative changes of coarse and fine rhythms in grain-size since 150 ka BP, and the grain-size parameters Mz,σ, Sk, Kg and SC/D also respond to the situation of multi-fluctuational alternations between peak and valley values. Simultaneity the grain-size eigenvalues F5, F16, F25, F50, F75, F84 and F95 are respondingly manifested as greatly cadent jumpiness. Hereby, the Milanggouwan section can be divided into 27 grain-size coarse and fine sedimentary cycles, which can be regarded as a real and integreted record of climate-geological process of desert vicissitude resulted from the alternative evolvement of the ancient winter and summer monsoons of East Asia since 150 ka BP.

关键词： Salawusu River valley Milanggouwan section 150 ka BP grain-size palaeoclimate cycles

Multi-Objective Optimization for China's Power Carbon Emission Reduction by 2035

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Journal of Thermal Science 2019年第2期28卷 184-194页

作者： WU Jianjun TANG Guihua WANG Run SUN Yanwei Key lab.of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences University of Chinese Academy of Sciences MOE Key lab.ratory of Thermo-Fluid Science and Engineering Xi'an Jiaotong University Hubei University geography & Spatial Information Techniques Department of Ningbo University

Low carbon transformation plays an important role in promoting the energy production and consumption revolution. Currently, the power sector of China still faces a series of challenges, such as the overcapacity of coal-fired power, the renewable energy consumption, the new constraints of carbon-emissions, and fragmented power planning. This study develops a multi-objective optimization model to predict the future trend of China power structure by 2035. The key factors such as network, power, load and storage are taken into account. Besides, the technical feasibility, economic rationality and social acceptable constraints are also fully considered. Through planning and optimization, the premise of low carbon transformation is to ensure the continuity of existing policies for removing inefficient assets, and the core is to develop and utilize non-fossil energy on a large scale. Specifically, the capacity of coal-fired power will be attained in the peak in 2025, and the factor will also transfer from main power supplier to main power and energy supplier. Before 2025, the clean replacement of incremental power installation will be completed. In 2035, 92% of new investment comes from non-fossil energy. The economy and competitiveness of wind power and PV(Photovoltaic) power generation are continuously increasing. By 2020, the coal-fired power and the wind power in eastern of China will be parity firstly. In 2025, the cost of PV and wind power will be the same. Furthermore, the evaluation dimension of modern power system with clean, low-carbon, safety and high efficiency are innovatively constructed, and the index system target of 2035 is quantitatively analyzed and prospected.

关键词： power sector carbon emission reduction optimization energy outlook comprehensive evaluation