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Scenario simulation and forecast of land use/cover in northern china

Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： li yuechen 1,2,3.& he chunyang 3.1 college of geographical science, chongqing normal university, chongqing 400047, china 2 college of Resources and Environmental science, chongqing university, chongqing 400044, china 3 college of Resources science & Technology, Beijing normal university, Beijing 100875, china college of geographical science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental science Chongqing University Chongqing 400044 China college of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

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Discrimination between Demodex folliculorum(Acari:Demodicidae) isolates from china and Spain based on mitochondrial cox1 sequences

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Journal of Zhejiang university-science B(Biomedicine & Biotechnology) 2013年第9期14卷 829-836页

作者： Ya-e ZHAO Jun-xian MA li HU li-ping WU Manuel DE ROJAS Department of Immunology and Pathogen Biology Xi'an Jiaotong University College of Medicine Department of Microbiology and Parasitology Faculty of PharmacyUniversity of Sevilla

For a long time,classification of Demodex mites has been based mainly on their hosts and phenotypic characteristics.A new subspecies of Demodex folliculorum has been proposed,but not ***,cox1 partial sequences of nine isolates of three Demodex species from two geographical sources(china and Spain) were studied to conduct molecular identification of *** showed that the mitochondrial cox1 fragments of five *** isolates from the facial skin of Chinese individuals were 429 bp long and that their sequence identity was 97.4%.The average sequence divergence was 1.24% among the five Chinese isolates,0.94% between the two geographical isolate groups(china(5) and Spain(1)),and 2.15% between the two facial tissue sources(facial skin(6) and eyelids(1)).The genetic distance and rate of third-position nucleotide transition/transversion were 0.0125,2.7(3.1) among the five Chinese isolates,0.0094,3.1(3.1) between the two geographical isolate groups,and 0.0217,4.4(3.1) between the two facial tissue *** trees showed that *** from the two geographical isolate groups did not form sister clades,while those from different facial tissue sources *** to the molecular characteristics,it appears that subspecies differentiation might not have occurred and that *** isolates from the two geographical sources are of the same ***,population differentiation might be occurring between isolates from facial skin and eyelids.

关键词： Demodex folliculorum cox1 partial sequences Divergence Genetic relationship Phylogenetic tree

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The GROUNDWATER RESOURCES AND ITSSUSTAINABLE DEVELOPMENTIN The SOUTH EDGE OF TARIM BASIN

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Chinese geographical science 2001年第1期11卷 57-62页

作者： MA Jin-zhu, li Ji-jun (college of Resources & Environment, Lanzhou university, Lanzhou 730000, P. R. china) college of Resources & Environment Lanzhou University Lanzhou P. R. China

There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05 × 109m3/a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60.4%, while spring water reducing 35.6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85 × 109m3/a with the recharge reducing to 3.1 × 109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glaoier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.

关键词： groundwater resources sustainable development safe yield Tarim Basin

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Land cover dynamic changes in northern china： 1989-2003

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Journal of geographical sciences 2008年第1期18卷 85-94页

作者： li yuechen college of geographical science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental science Chongqing University Chongqing 400044 China college of Resources science ＆ Technology Beijing Normal University Beijing 100875 China

The 13 provinces （autonomous regions and municipalities） in northern china are located in latitude 31°-54°N and longitude 73°-136°E including Beijing, Tianjin, hebei, Shanxi, Inner Mongolia, Jilin, liaoning, heilongjiang, Shaanxi, Gansu, Ningxia, Qinghai, and Xinjiang, where environments are fragile. In recent years, the eco-environmental problems such as vegetation destruction, desertification and soil erosion etc. become serious because of climate change and unreasonable human activities. In this paper, landscape pattern and its evolution in northern china from 1989 to 2003 was investigated by the combined use of RS and GIS based on the basic theory and method of landscape ecology. Land use/cover maps of the study area in 1989, 1999 and 2003 were produced by using 1 km monthly NOAA Advanced Very High Resolution Radiometer （AVHRR） and SPOTNGT normalized Difference Vegetation Index （NDVI） dataset from national climate bureau of china which were geo-registered to Lambert azimuthal equal-area map projection and were used in the paper. Landscape evolution in the area over the study period was investigated by two methods：（a） the changes of various landscape metrics were analyzed using the landscape structure analysis program FRAGSTATS; （b） the transition matrix of landscape patch types was calculated with the help of the RS and GIS software. The results showed that from 1989 to 2003, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The diversity index and evenness index increased during the period, which means that the landscape pattern tended to be diversified and even. The fragmentation index of grassland, forestland and water areas also increased significantly. This showed that the distribution and structure of forestland, grassland and water areas had been changed greatly during the period, especially grassland which became more and more fragmentized, and its fragmentation index increased from 19.23%

关键词： landscape pattern land use/cover northern china

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Evaluation on the human settlements environment suitability in the Three Gorges Reservoir Area of chongqing based on RS and GIS

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Journal of geographical sciences 2011年第2期21卷 346-358页

作者： li yuechen college of Geography and Tourism Chongqing Normal University Chongqing 400047 China Key Laboratory of GIS Application Chongqing Municipal Education Commission Chongqing 400047 China

To explore geographical differences in quantitative characteristics and spatial pattern of human settlements environmental suitability （HSES） in the Three Gorges Reservoir Area （TGRA）, terrain, climate, hydrology, vegetation and other natural factors were selected to build the livable environmental evaluation, and the quantitative analysis was conducted through Remote Sensing（RS） and Geographic Informational System （GIS） to reveal geo- graphical characteristics and spatial patterns of HSES. The results are obtained as follows：（1） inhabitants of the TGRA of chongqing are concentrated in the area with moderate *** HSES, which is 78% of the total population distributed in 48% of the study area; （2） the HSES is closely related to the terrain, and it forms an arc-banded spatial succession pattern： relatively low in the northeast and the southeast while comparatively high in the west and the south; （3） large numbers of people are distributed in the area with low suitability （with higher population density than the average of the western china）, but economic development level in these areas is quite low. Moreover, these areas are ecological sensitive and fragile, many kinds of eco-environmental problems have been caused by human activities. Therefore, population migration and layout are reasonable options for the development of these areas.

关键词： Three Gorges Reservoir Area of chongqing human settlements environment suitability GIS RS

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Quantitative estimation of climate change effects on potential evapotranspiration in Beijing during 1951-2010

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Journal of geographical sciences 2014年第1期24卷 93-112页

作者： liU Haijun li Yan JOSEF Tanny ZHANG Ruihao HUANG Guanhua college of Water sciences Beijing Normal University Beijing 100875 China college of Water Resources and Civil Engineering China Agricultural University Beijing 100083 China Institute of Soil Water and Environmental Sciences Agricultural Research Organization The Volcani CenterP. O. Box 6 Bet Dagan 50250 Israel State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100048 China

℃ Climate change is likely to affect hydrological cycle through precipitation, evapotranspiration, soil moisture etc. In the present study, an attempt has been made to study the climate change and the sensitivity of estimated evapotranspiration to each climatic variable for a semi-arid region of Beijing in North china using data set from 1951 to 2010. Penman-Monteith method was used to calculate reference crop evapotranspiration （ETo）. Changes of ETo to each climatic variable was estimated using a sensitivity analysis method proposed in this study. Results show that in the past 60 years, mean temperature and vapor pressure deficit （VPD） were significantly increasing, relative humidity and sunshine hours were significantly decreasing, and wind speed greatly oscillated without a significant trend. Total precipitation was significantly decreasing in corn season （from June to September）, but it was increasing in wheat season （from October to next May）. The change rates of tem- perature, relative humidity, VPD, wind speed, annual total precipitation, sunshine hours and solar radiation were 0.42℃, 1.47%, 0.04 kPa, 0.05 m.s-1, 25.0 mm, 74.0 hours and 90.7 MJ.m-2 per decade, respectively. In the past 60 years, yearly ETo was increasing with a rate of 19.5 mm per decade, and total ETos in wheat and corn seasons were increasing with rates of 13.1 and 5.3 mm per decade, respectively. Sensitivity analysis showed that mean air temperature was the first key factor for ETo change in the past 60 years, causing an annual total ETo increase of 7.4%, followed by relative humidity （5.5%） and sunshine hours （-3.1%）; the less sensitivity factors were wind speed （0.7%）, minimum temperature （-0.3%） and maximum temperature （-0.2%）. A greater reduction of total ETo （12.3%） in the past 60 years was found in wheat season, mainly because of mean temperature （8.6%） and relative hu- midity （5.4%）, as compared to a reduction of 6.0% in ETo during corn season due to sunshinehours （-6.9%）, relative

关键词： climatic variables reference crop evapotranspiration Penman-Monteith equation changing trend sensitivity analysis

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Spatiotemporal features of soil and water loss in Three Gorges Reservoir Area of chongqing

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Journal of geographical sciences 2009年第1期19卷 81-94页

作者：李月臣刘春霞袁兴中 college of Resources and Environmental science Chongqing University college of geographical science Chongqing Normal University Key Laboratory of GIS Application Chongqing Municipal Education Commission

Soil and water loss has been the most serious eco-environmental problem in the Three Gorges Reservoir Area of *** this paper the authors studied the spatiotemporal features of soil and water loss from 1999 to 2004 based on RS and GIS *** results showed that:(1) The soil and water loss area decreased from 1999 to 2004.(2) Soil and water loss mainly exists in purple soil,yellow soil,limestone soil,paddy soil and yellow brown soil distributed areas.(3) The dry slope land and sparse woodland that are intensively influenced by human activities experienced most serious soil and water loss.(4) Soil and water loss in the study area indicated an obvious vertical differentiation characteristic.(5) There is a significant correlation between soil and water loss and slope.(6) There is no obvious correlation between soil and water loss and aspect.(7) Soil and water loss mainly exists in the values of R between 300 and 340 distribution *** very-high soil and water loss has obvious correlation with R.

关键词： soil and water loss chongqing Three Gorges Reservoir Area

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基于地理加权相关的区域经济与民航运输空间关系分析

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重庆师范大学学报（自然科学版） 2019年第4期36卷 122-130页

作者：汪言在李月臣汪洋重庆市高校地理信息系统应用研究重点实验室重庆师范大学地理与旅游学院重庆401331

【目的】以第三产业增加值为经济增长需求指标,以旅客吞吐量、货邮吞吐量为民航运输生产供给指标,分析区域经济增长与民航运输生产的空间关系。【方法】使用地理加权相关分析计算地理加权相关系数,使用经验正交函数分析空间相关性变化... 详细信息

【目的】以第三产业增加值为经济增长需求指标,以旅客吞吐量、货邮吞吐量为民航运输生产供给指标,分析区域经济增长与民航运输生产的空间关系。【方法】使用地理加权相关分析计算地理加权相关系数,使用经验正交函数分析空间相关性变化的主要空间分布模式。【结果】第三产业与民航运输的空间相关性整体呈东部弱-西部强分布结构;近年来,第三产业与民航运输生产的空间相关性整体呈减弱变化趋势,中西部地区二者相关性逐年减弱是导致全国空间相关性减弱的主要驱动因素;通常情况下,省市经济规模越大,则它的第三产业与民航运输的相关性越弱。【结论】受经济产业活动聚集效应影响,东部发达省市经济增长对民航运输的依赖性普遍较弱,中西部省市对民航运输的依赖性较强;尽管近年来全国尺度上经济活动对民航运输的依赖性逐年减弱,但在经济增速放缓背景下,民航运输对中东部省市经济增长的拉动作用逐年增强。

关键词：民航运输区域经济增长空间关系地理加权相关

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重庆市战略性新兴产业空间集聚测度及时空演变分析

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重庆师范大学学报（自然科学版） 2018年第5期35卷 63-71页

作者：祝汉收刘春霞李月臣重庆师范大学地理与旅游学院重庆师范大学三峡生态环境遥感研究所重庆市高校GIS应用研究重点实验室重庆401331

【目的】战略性新兴产业能够带动未来区域经济的发展,深入研究这些产业的空间特征对区域内产业空间结构优化调整有重大意义。【方法】运用Ripley’s K函数、核密度分析等方法研究了战略性新兴产业的地理集聚特征及空间演变特征,并引入... 详细信息

【目的】战略性新兴产业能够带动未来区域经济的发展,深入研究这些产业的空间特征对区域内产业空间结构优化调整有重大意义。【方法】运用Ripley’s K函数、核密度分析等方法研究了战略性新兴产业的地理集聚特征及空间演变特征,并引入空间化的GDP数据分析了产业分布与GDP的关系。【结果】重庆市战略性新兴产业集聚化特征明显,各类产业集聚程度均呈增加趋势,但不同产业类型的集聚特征存在显著差异;4个时期的最高核密度值依次为:0.47,3.30,16.33,29.06,核密度最高值均出现在主城区;战略性新兴产业的平均中心移动轨迹整体表现为由东北逐渐向西南方向偏移;战略性新兴产业的时空演变规律与空间化的GDP数据高度吻合。【结论】研究探明了重庆市战略性新兴产业空间格局演变的特征,并印证了战略性新兴产业与区域GDP之间存在必然的联系,为相关部门在宏观上对战略性新兴产业的调控和布局提供了有效的依据。

关键词：重庆市战略性新兴产业时空演变 GDP空间化

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The Relationship Between Fat Content and Biological Parameters of Bigeye Tuna(Thunnus obseus) in the Western Central Indian Ocean

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Journal of Ocean university of china 2016年第5期15卷 853-860页

作者： SONG liming SheN Zhibin li Jie li Dongjing li Yuwei college of Marine sciences Shanghai Ocean University Shanghai 201306 P. R. China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean University Shanghai 201306 P. R. China The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of Education Shanghai Ocean University Shanghai 201306 P. R. China Collaboration Innovation Center for National Distant-Water Fisheries Shanghai 201306 P. R. China

Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model(GAM) was used to analyze the relationships between fat content and fork length(FL), gonadosomatic index(GSI), condition factor(K), and somatic index(SI). Results showed that: 1) the fat content of bigeye tuna was in the range of 3.1%–27.1% with the average 12.8%; 2) there were no significant geographical differences of average fat content(P > 0.05) among 1? squares in general; 3) there were no significant differences(P > 0.05) of the fat content for different genders, months, or gonad maturity stages; 4) there was an extremely significant correlation(P = 0.000) between fat content and FL and GSI. There was no significant correlation(P = 0.051) between fat content and K. There was a significant correlation(P = 0.003) between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.

关键词： maturity Indian season somatic physiological maturation extremely migration length feeding

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