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河北省567名汉族人苯硫脲尝味能力的测定
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作者 刘慧芬 魏会平 +5 位作者 朱玉青 辛春艳 胡卫江 赵秀丽 杨春玫 李荣 《神经药理学报》 1992年第4期23-25,共3页
本文是运用阈值法对河北汉族人进行苯硫脲(PTC)味盲基因频率的研究。此项研究总共调查了567名河北汉族人。研究结果说明在河北汉族人当中味盲基因频率大约为0.2449;并且得知性别对PTC尝味能力无显著影响。
关键词 国值 平均国值 味盲基丙频率
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一类复调和函数的Riemann边值问题 被引量:5
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作者 张建元 《宁夏大学学报(自然科学版)》 CAS 1996年第1期70-71,78,共3页
一类复调和函数的Riemann边值问题张建元(云南昭通师专教学系,657000,云南昭通)1基本概念定义1.1在区域G中具有如下形式:F(Z)十以Z)(其中F(Z)和中(Z)分别是共轭解析和解析的函数)的函数称为混合... 一类复调和函数的Riemann边值问题张建元(云南昭通师专教学系,657000,云南昭通)1基本概念定义1.1在区域G中具有如下形式:F(Z)十以Z)(其中F(Z)和中(Z)分别是共轭解析和解析的函数)的函数称为混合型解析函数.所有混合型解析函数的全... 展开更多
关键词 复调和函数 黎曼边值问题 国值问题
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Visualization of uncertainty associated with spatial prediction of continuous variables using HSI color model:a case study of prediction of pH for topsoil in peri-urban Beijing,China 被引量:1
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作者 檀满枝 陈杰 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期319-322,共4页
Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of to... Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of topsoil in the peri-urban Beijing. A two-dimensional legend was designed to accompany the visualization-vertical axis (hues) for visualizing the predicted values and horizontal axis (whiteness) for visualizing the prediction error. Moreover, different ways of visualizing uncertainty were briefly reviewed in this paper. This case study indicated that visualization of both predictions and prediction uncertainty offered a possibility to enhance visual exploration of the data uncertainty and to compare different prediction methods or predictions of totally different variables. The whitish region of the visualization map can be simply interpreted as unsatisfactory prediction results, where may need additional samples or more suitable prediction models for a better prediction results. 展开更多
关键词 Hue-Saturation-Intensity color model spatial prediction UNCERTAINTY VISUALIZATION
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Performance value of high risk factors in colorectal cancer screening in China 被引量:44
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作者 Wen Meng Shan-Rong Cai +3 位作者 Lun Zhou Qi Dong Shu Zheng Su-Zhan Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第48期6111-6116,共6页
AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) an... AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation.Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy.RESULTS:The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia.The iFOBT had the highest sensitivity,lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas.A history of chronic cholecystitis or cholecystectomy,chronic appendicitis or appendectomy,and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas.The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for nonadenomatous polyps.A history of chronic appendicitis or appendectomy,chronic constipation,chronic diarrhea,mucous and bloody stool,CRC in first degree relatives,malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps.Except for a history of malignant tumor in screening for non-adenomatous polyps,the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality.CONCLUSION:The iFOBT may be the best marker for screening for advanced neoplasias and adenomas.Some unique high risk factors may play an important role in CRC screening in China. 展开更多
关键词 Colorectal cancer Cancer screening FECES Occult blood Risk factors Predictive value of tests
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An analysis of China's CO_2 emission peaking target and pathways 被引量:15
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作者 HE Jian-Kun 《Advances in Climate Change Research》 SCIE 2014年第4期155-161,共7页
China has set the goal for its CO2 emissions to peak around 2030, which is not only a strategic decision coordinating domestic sustainable development and global climate change mitigation but also an overarching targe... China has set the goal for its CO2 emissions to peak around 2030, which is not only a strategic decision coordinating domestic sustainable development and global climate change mitigation but also an overarching target and a key point of action for China's resource conservation, environmental protection, shift in economic development patterns, and CO2 emission reduction to avoid climate change. The development stage where China maps out the CO2 emission peak target is earlier than that of the developed countries. It is a necessity that the non-fossil energy supplies be able to meet all the increased energy demand for achieving CO2 emission peaking. Given that China's potential GDP annual increasing rate will be more than 4%, and China's total energy demand will continue to increase by approximately 1.0%--1.5% annually around 2030, new and renewable energies will need to increase by 6%-8% annually to meet the desired CO2 emission peak. The share of new and renewable energies in China's total primary energy supply will be approximately 20% by 2030. At that time, the energy consumption elasticity will decrease to around 0.3, and the annual decrease in the rate of CO2 intensity will also be higher than 4% to ensure the sustained growth of GDE To achieve the CO2 emission peaking target and substantially promote the low-carbon deve!opment transformation, China needs to actively promote an energy production and consumption revolution, the innovation of advanced energy technologies, the reform of the energy regulatory system and pricing mechanism, and especially the construction of a national carbon emission cap and trade system. 展开更多
关键词 CO2 emission peak Energy revolution Climate change China's carbon emission mitigation target
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Ecological Footprint and Major Driving Forces in West Jilin Province, Northeast China 被引量:16
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作者 WANG Mingquan LIU Jingshuang +1 位作者 WANG Jinda ZHAO Guangying 《Chinese Geographical Science》 SCIE CSCD 2010年第5期434-441,共8页
The environmental impact caused by local people (ecological footprint of consumption, EFc) and the actual environmental impact that the ecosystem burdens (ecological footprint of production, EFp) in West Jilin Pro... The environmental impact caused by local people (ecological footprint of consumption, EFc) and the actual environmental impact that the ecosystem burdens (ecological footprint of production, EFp) in West Jilin Province, Northeast China from 1986 to 2006 were evaluated by using ecological footprint (EF) method. And the major driving forces of EFc and EFp were analyzed by STIRPAT model. Both EFc and EFp showed increasing trends in 1986-2006, accompanied by decreasing ecological deficits but expanding ecological overshoots. Population (P), GDP per capita (A1), quadratic term of GDP per capita (A2), urbanization (Tα1), and quadratic term of urbanization (Ta2) were important influencing factors of EFc, among which Tα2 and Tα1 were the most dominate driving forces of EFc. A1, A2 and Tα2 were important influencing factors of EFp, among which A2 and A1 were the most dominate driving forces of EFp. In 1986-2006, the classical Environmental Kuznets Curve hypothesis did not exist between A2 and EF (both EFc and EFp), but did between Tα2 and EF. The results indicate that enhancing the urbanization process and diversifying economic sources is one of the most effective ways to reduce the environmental impact of West Jilin Province. Moreover, importance should be attached to improve the eco-efficiency of resource exploitation and consumption. 展开更多
关键词 ecological footprint STIRPAT model ecological deficit ecological overshoot West Jilin Province
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Water-Soluble Rare Earth Elements in Some Soils of China 被引量:3
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作者 ZHUJIANGUO SUNJUN 《Pedosphere》 SCIE CAS CSCD 1997年第1期25-30,共6页
Water-soluble rare earth elements (WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer. Results showed that the contents of WSREEs dec... Water-soluble rare earth elements (WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer. Results showed that the contents of WSREEs decreased from upper layer to lower layer of soils in the southern part of China with a high rainfall and low pH but increased for soils in the northern part of China with a low rainfall and relatively higher pH. Contents of WSREEs in soils were lower than 100 μg kg-1 in most casest and varied greatly with both different soils and different layers of the same profile. The highest content was 2816.3 μg kg-1 but the lowest was 17.6 μg kg-1 only. The content of individual rare earth iement (REE) in the soil solution also varied greatly with the highest one ranging from 8.4 to 1373 μg kg-1 for Ce and the lowest one from 0.05to 4.48 μg kg-1 for Lu. The sum of WSREEs in the first soil layers ranged from 121.5 to 345.6 μg kg-1.Great variations existed among ratios of REEs extracted with water to the total REEs of soils, ranging from 0.02×10-3 to 13.2×10-3. But as the upper layer was considered, the ratio showed only a small difference,ranging from 0.79×10-3 to 1.69×10-3. 展开更多
关键词 rare earth element soil profiles ICP-MS
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Characteristics of Extreme Temperature Event and Its Response to Regional Warming in Northwest China in Past 45 Years 被引量:17
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作者 YANG Jinhu REN Chuanyou JIANG Zhihong 《Chinese Geographical Science》 SCIE CSCD 2008年第1期70-76,共7页
Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesim... Using the daily maximum and minimum temperature dataset from 128 stations from 1960 to 2004 in Northwest China,daily extreme high temperature(EHT)and extreme low temperature(ELT)thresholds were deter-mined by centesimal method for different stations at first,then yearly EHT and ELT events were counted up in differ-ent stations,and the characteristics of their spatio-temporal distribution were diagnosed at last.The study drew follow-ing conclusions:1)The consistent anomaly distribution characteristic was the most important mode of the EHT and ELT events in Northwest China.2)The spatial distribution of the EHT and ELT events can be divided into five sub-regions,namely,the north of Qinghai and west of Gansu,the north of Xinjiang,the south of Xinjiang,the east of Northwest China and the south of Qinghai.3)The EHT events showed remarkable increasing trend in all of five sub-regions,but only in the north of Qinghai and west of Gansu area,sudden change phenomenon occurred;the ELT events showed decreasing trend in all of five sub-regions,and sudden change phenomenon occurred in Northwest China except for south of Qinghai.4)In all of five sub-regions the EHT events showed remarkable 12-14yr period os-cillation,and the ELT event showed significant 13-15yr and 7-8yr period oscillation.5)The EHT and ELT events displayed remarkable positive and negative responses to regional warming of Northwest China respectively. 展开更多
关键词 extreme temperature response to warming Northwest China
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Regional Financial Development and Regional Economic Growth: An Empirical Analysis of Suzhou City, China 被引量:2
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作者 LIU Yong LI Weiping 《Chinese Geographical Science》 SCIE CSCD 2010年第3期269-274,共6页
There are many defects in researches on the relationship of the regional financial development (FD) and economic growth of China, such as simply assuming the causality direction, not highlighting financial institution... There are many defects in researches on the relationship of the regional financial development (FD) and economic growth of China, such as simply assuming the causality direction, not highlighting financial institution, using incomplete financial indicator, etc. This article, taking Suzhou City of Jiangsu Province, China as a case, builds a simple model to study the level of FD from three aspects of financial scale, structure and institution. Three original indicators of PRIVY (private investment/aggregate investment), DEPTH (aggregate loan/GDP) and FDIVG (FDI/GDP) are used to construct the FD economic indicator through Principal Component Analysis approach. Then we use Granger method to analyze the relationship between the FD and the economic growth of Suzhou. Empirical test results show that the FD of Suzhou is the Granger reason of economic growth, while economic growth is not the reason for FD, because the relationship between the FD and the economic growth of Suzhou is just in the ″supply-leading″ period. In terms of Suzhou experiences, the local government should strengthen the protection of private investment, improve the institutional environment, and establish the reasonable financial structure. So we can concluded that FD could play a great role in promoting economic growth at the economy takeoff stage. 展开更多
关键词 financial development regional economic growth INSTITUTION Granger Causality Analysis
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Debris Flow Warning Threshold Based on Antecedent Rainfall:a Case Study in Jiangjia Ravine,Yunnan,China 被引量:11
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作者 GUO Xiao-jun CUI Peng LI Yong 《Journal of Mountain Science》 SCIE CSCD 2013年第2期305-314,共10页
Debris flows in Jiangjia Ravine in Yunnan province, China are not only triggered by intense storms but also by short-duration and low-intensity rainfalls. This reflects the significance of antecedent rainfall. This pa... Debris flows in Jiangjia Ravine in Yunnan province, China are not only triggered by intense storms but also by short-duration and low-intensity rainfalls. This reflects the significance of antecedent rainfall. This paper tries to find the debris flow- triggering threshold by considering antecedent rainfall through a case study in Jiangjia Ravine. From 23 debris flow events, the I-D (Intensity-Duration) threshold was found, which is very dose to the line of 95th percentile regression line of rainfall events, representing that 95% of rainfalls can potentially induce debris flows and reflects the limitation of I-D threshold application in this area. Taking into account the effect of antecedent rainfall, the debris flowtriggering threshold for rainfall quantity and intensity is statistically and empirically derived. The relationships can be used in debris flow warning system as key thresholds. Coupling with the rainfall characteristics in this area, new thresholds are proposed as triggering and warning thresholds. 展开更多
关键词 I-D threshold debris flow warningsystem antecedent rainfall Jiangjia Ravine
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EVALUATION OF ECOLOGICAL SERVICES OF JILIN PROVINCE, NORTHEAST CHINA 被引量:2
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作者 YUShu-xia SHANGJin-cheng GUOHuai-cheng 《Chinese Geographical Science》 SCIE CSCD 2004年第3期215-220,共6页
The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic... The main purpose of this study is to give evaluation of ecological services of Jilin Province, Northeast China. To take this value into decision-making and GDP accounting system is considered to be one of the economic solutions for ecological problems. The evaluation is based on the methods proposed by COSTANZA et al., and some modifications about unit value of forest and cropland system were made according to the real characters of ecosystem, climate, natural conditions etc., in Jilin Province. Total value of ecosystem services is about 554.404x10(9) yuan(RMB)/a, which is about 4.9 times of GDP of the corresponding period. The results of this study could be used as a fundamental work for the construction of ecological province, which was carried out from 2001, and could provide ecological information for decision-making. Furthermore, the necessities for the further studies on the evaluation of ecological services and natural capital were discussed. 展开更多
关键词 ecological services economic evaluation sustainable development strategic decision-making Jilin Province
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Estimating Ecological Value of Small Hydropower Using Contingent Valuation Method:An Application to Tongjiqiao Reservoir in Zhejiang Province,China 被引量:1
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作者 Han Hongyun Zhao Liange Zhang Tong 《Chinese Journal of Population,Resources and Environment》 2012年第1期87-95,共9页
The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an ap... The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector. 展开更多
关键词 small hydropower ecosystem service contingentvaluation method WTP
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Economic Valuation of Health Impact of PM_(10) Pollution in Beijing from 2001 to 2006 被引量:2
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作者 Zou Wenbo Zhang Shiqiu 《Chinese Journal of Population,Resources and Environment》 2010年第2期68-74,共7页
In light of the practical need for research to inform policy in Beijing,this study evaluates the economic cost of the impact of PM 10 pollution in Beijing from 2001 to 2006,taking health as the main impact,and mortali... In light of the practical need for research to inform policy in Beijing,this study evaluates the economic cost of the impact of PM 10 pollution in Beijing from 2001 to 2006,taking health as the main impact,and mortality as the main outcome.Based on the literature review,this study adopts relatively conservative parameters as the basis for calculating the health impacts.It concludes that nearly 30%of mortality among registered residents above age 30 in Beijing can be attributed to PM 10 pollution,and that the economic cost equals 0.8%-1.2%of the city's GDP over the same period.This is lower than the results of previous studies,but still high enough to warrant a commitment to solve the city's air pollution problem. 展开更多
关键词 health impact economic valuation MORTALITY MORBIDITY PM10 air pollution
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Wetland Economic Valuation Approaches and Prospects in China 被引量:3
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作者 JIANG Bo Christina P.WONG +1 位作者 CUI Lijuan OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2016年第2期143-154,共12页
Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-bein... Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-being explicit. Economic valuation can help management by clarifying the full range of benefits and costs of proposed management actions. In the past two decades, economic valuation of wetland ecosystem services has become one of the most significant scientific priorities for wetland protection. In this paper, we provide an overview of ecosystem services, and summarize the main interdisciplinary approaches to measure and value wetland ecosystem services. We identified four main methodological gaps preventing progress on wetland valuation of ecosystem services in China, which are: 1) confusion on terminology like intermediate and final ecosystem services, 2) lack of ecological production functions to link ecosystem characteristics to final ecosystem services, 3) static valuation making it difficult to evaluate the trade-offs and synergies among ecosystem services, and 4) lack of clear guidance on relating ecological compensation programs to conservation targets. Overcoming these gaps is important to inform wetland compensation mechanisms and conservation policies. We propose future research on wetland ecosystem services in China should be focused on: 1) defining final ecosystem services based on beneficiary preferences and underlying biophysical mechanisms, 2) establishing wetland monitoring programs at specific sites to collect data on final ecosystem service indicators and ecosystem characteristic metrics to create ecological production functions for economic valuation and rescaling techniques, and 3) incorporating wetland ecosystem service values into decision-making processes to inform wetland management. 展开更多
关键词 ecosystem services wetlands economic valuation methodological gaps China
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Eco-compensation of Wetlands in Yellow River Delta of Shandong Province,China 被引量:3
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作者 HAN Mei CUI Jinlong +2 位作者 HAO Zhen WANG Yi WANG Renqing 《Chinese Geographical Science》 SCIE CSCD 2012年第1期119-126,共8页
Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becom... Wetlands play an important ecological role and provide many functions for people, yet wetlands are cur- rently decreasing and deteriorating. The ability to calculate an economic value for the loss of wetlands is becoming in- creasingly important for policy makers. In this study, remote sensing, field investigations, department visits, and other methods were used to survey wetland types, assess wetland area changes, and calculate wetland economic value. Mar- ket value loss and ecological ftmction value loss, caused by reduction of wetland area and environmental pollution were calculated using commonly accepted methods of market valuation, ecological valuation, environmental protection investment cost analysis, and outcome parameters. According to market value loss and ecological function value loss, preliminarily fund allocation for wetland and ecological compensation was calculated. This will provide an important reference for future Yellow River Delta eco-compensation studies. 展开更多
关键词 Yellow River Delta WETLAND eco-compensation compensation standard
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Effects of Topography and Land Use Change on Gully Development in Typical Mollisol Region of Northeast China 被引量:12
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作者 LI Hao Richard M CRUSE +1 位作者 LIU Xiaobing ZHANG Xingyi 《Chinese Geographical Science》 SCIE CSCD 2016年第6期779-788,共10页
Due to high intensity agricultural exploitation since the middle of the 20 th century, farmland gullies have become a pervasive form of water erosion in Northeast China. Yet few researches are concentrated on how topo... Due to high intensity agricultural exploitation since the middle of the 20 th century, farmland gullies have become a pervasive form of water erosion in Northeast China. Yet few researches are concentrated on how topography and land use affect long-term gully development in this region. In this study, gully distribution in a village with an area of 24.2 km^2 in the central Mollisols area of Northeast China in different times were compared by Aerial photography(1968), Quickbird image(2009) and field survey, and factors affecting gully development including land use and topography were analyzed. The results showed that the total gully number decreased from 104 to 69, while occupying area rose from 34.8 ha to 78.4 ha from 1968 to 2009. Fundamental gully distribution had been formed by 1968 as most of 2009′s gullies were evolved from 1968′s gullies′ merge and width expansion process, and new gullies those initiated after 1968 occupied only 7% of total gully area in 2009. Gully area increasing ratio in grassland was the highest and that in forestland was the lowest. The threshold catchment area between simple and complex gully development was around 15 ha to 25 ha. This threshold value sets apart catchment areas that will develop simple or complex gullies in areas with similar environmental conditions. Gully control measurements were urgent because if appropriate gully control implements would not be applied, present gully erosion crisis could be doubled within 50 years. 展开更多
关键词 gully erosion land use topographic threshold MOLLISOLS Northeast China
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Changes of Biogenic Elements in Phragmites australis and Suaeda salsa from Salt Marshes in Yellow River Delta,China 被引量:8
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作者 JIA Jia BAI Junhong +4 位作者 WANG Wei ZHANG Guangliang WANG Xin ZHAO Qingqing ZHANG Shuai 《Chinese Geographical Science》 SCIE CSCD 2018年第3期411-419,共9页
Little information is available on biogenic elements(carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nit... Little information is available on biogenic elements(carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nitrogen, phosphorus and sulfur of plants, and their ecological stoichiometric characteristics in the Yellow(Huanghe) River Delta, plant samples were collected from two typical salt marshes(Suaeda salsa and Phragmites australis wetlands) during the period of from August to October in 2007, and the ratios of C/N, C/P, N/P, C/N/P and C/N/P/S were calculated. Results showed that during the studying period, plant C, N and P were lower than the global average values, and plant N and P were lower than the China's average values. Leaf C and S in Suaeda salsa were significantly lower than those in Phragmites australis(P < 0.05), and leaf N and P in Suaeda salsa and Phragmites australis showed no significant differences(P > 0.05). Average C/N ratios were 23.75 in leaf, 73.36 in stem, 65.67 in root of Suaeda salsa, and 33.77 in leaf, 121.68 in stem, 97.13 in root of Phragmites australis. Average C/N ratios of Suaeda salsa and Phragmites australis were all great than 25, indicating the salt marsh in the Yellow River Delta is an N limitation system. Average C/P ratios were 276.78 in leaf, 709.28 in stem and 1031.32 in root of Suaeda salsa, and 536.94 in leaf, 768.13 in stem and 875.22 in root of Phragmites australis. The average N/P ratios of Suaeda salsa were 12.92 in leaf, 10.77 in stem and 10.91 in root, and the average N/P ratios of Phragmites australis were 16.40 in leaf, 7.40 in stem and 6.92 in root, indicating the Suaeda salsa wetlands were N limited and Phragmites australis wetlands were N limited in August and P limited in October in 2007. The average C/N, C/P and C/N/P ratios in Suaeda salsa and Pragmites australis were higher than the global average values, indicating the lower quality of organic matter provided by wetland plants in the Yellow River delta. 展开更多
关键词 biogenic elements Phragmites australis Suaeda salsa salt marsh Yellow River Delta
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The Form and Comparison of Value between China and Western Countries 被引量:3
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作者 明虹 《Sino-US English Teaching》 2007年第3期70-72,共3页
Value is a criterion which can help people to distinguish good and bad, beauty and ugliness, fight and wrong and true and false. Value varies from different counties, which is the main cause of the conflict and misund... Value is a criterion which can help people to distinguish good and bad, beauty and ugliness, fight and wrong and true and false. Value varies from different counties, which is the main cause of the conflict and misunderstanding in communication between China and western countries. It is first introduced in this paper about how these differences are formed and then explain them in several ways. It is of great significance to know and learn the cultural differences in cross-cultural communication. 展开更多
关键词 CULTURE VALUE DIFFERENCE
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Threshold Effects in the Capital Account Liberalization and Foreign Direct Investment Relationship 被引量:1
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作者 Gammoudi Mouna Cherif Mondher 《Chinese Business Review》 2014年第9期562-577,共16页
This paper examines how capital account liberalization (CAL) affects foreign direct investment (FDI) inflows. Authors use a dynamic panel model encompassing 14 Middle East countries over the period from 1985 to 20... This paper examines how capital account liberalization (CAL) affects foreign direct investment (FDI) inflows. Authors use a dynamic panel model encompassing 14 Middle East countries over the period from 1985 to 2009. The findings suggest that countries that are able to reap the benefits of the capital openness policy satisfy certain threshold conditions regarding the level of financial development and institutional quality. Thus to promote FDI, governments in this region should develop a set of policies that not only focus on financial openness, but also on the improvement of the financial system and legal institutions. 展开更多
关键词 capital account liberalization (CAL) foreign direct investment (FDI) institutional quality system GMM estimator
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Numerical simulation of wave fi eld in the South China Sea using WAVEWATCH III 被引量:2
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作者 周良明 李占斌 +1 位作者 牟林 王爱方 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期656-664,共9页
Wave fields of the South China Sea (SCS) from 1976 to 2005 were simulated using WAVEWATCH III by inputting high-resolution reanalysis wind field datasets assimilated from several meteorological data sources. Compari... Wave fields of the South China Sea (SCS) from 1976 to 2005 were simulated using WAVEWATCH III by inputting high-resolution reanalysis wind field datasets assimilated from several meteorological data sources. Comparisons of wave heights between WAVEWATCH III and TOPEX/Poseidon altimeter and buoy data show a good agreement. Our results show seasonal variation of wave direction as follows: 1. During the summer monsoon (April-September), waves from south occur from April through September in the southern SCS region, which prevail taking about 40% of the time; 2. During the winter monsoon (December-March), waves from northeast prevail throughout the SCS for 56% of the period; 3. The dominant wave direction in SCS is NE. The seasonal variation of wave height Hs in SCS shows that in spring, Hs〉l m in the central SCS region and is less than 1 m in other areas. In summer, Hs is higher than in spring. During September- November, influenced by tropical cyclones, Hs is mostly higher than 1 m. East of Hainan Island, Hs〉2 m. In winter, Hs reaches its maximum value influenced by the north-east monsoon, and heights over 2 m are found over a large part of SCS. Finally, we calculated the extreme wave parameters in SCS and found that the extreme wind speed and wave height for the 100-year return period for SCS peaked at 45 m/s and 19 m, respectively, SE of Hainan Island and decreased from north to south. 展开更多
关键词 South China Sea (SCS) wave fields WAVEWATCH III (WW3) return period
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