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Ancient Changjiang channel system in the East China Sea continental shelf during the last glaciation

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Science China Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3. YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean University of China, Qingdao 266003. China 2. Shandong Key Laboratory of Sea Floor resource and Exploration Technique, Qingdao 266003. China 3. Qingdao institute of Marine Geology, Qingdao 266071, China 4. College of Marine Environment, Ocean University of China, Qingdao 266003. China 5. First Survey Team of Marine Geology, Shanghai Bureau of Petroleum, Shanghai 201208, China 1. College of Marine Geo-science Ocean University of China 266003 Qingdao China 2. Shandong Key Laboratory of Sea Floor resource and Exploration Technique 266003 Qingdao China 3. Qingdao institute of Marine Geology 266071 Qingdao China 4. College of Marine Environment Ocean University of China 266003 Qingdao China 5. First Survey Team of Marine Geology Shanghai Bureau of Petroleum 201208 Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East China Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

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论西部人力资源的开发与人力资本的积累

四川大学学报（哲学社会科学版） 2000年第5期 17-22页

作者：钟丽霞郑长德四川大学管理学院四川成都610064 西南民族学院企业管理系四川成都610064

人力资本的积累是经济发展的最重要的推动力，而西部地区的总体人力资本水平还很低，通过制度创新，加强人力投资强度，改革人力资本投资结构，加快西部地区劳动力市场建设，促进劳动力的自由流动，改革人才配置制度，就能有效地促使西... 详细信息

人力资本的积累是经济发展的最重要的推动力，而西部地区的总体人力资本水平还很低，通过制度创新，加强人力投资强度，改革人力资本投资结构，加快西部地区劳动力市场建设，促进劳动力的自由流动，改革人才配置制度，就能有效地促使西部地区人力资源的开发和人力资本的积累。

关键词：人力资源人力资本西部地区中国人才配置

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青城山森林植被常见种群种间联结性的研究

四川大学学报（自然科学版） 2004年第1期41卷 169-173页

作者：马丹炜王跃华王道模张果陈放四川师范大学生命科学学院成都610066 成都大学生物工程系成都610106 四川农业大学都江堰分校信息工程系都江堰611830 四川师范大学资源与环境学院成都610066 四川大学生命科学学院成都610064

采用2×2列联表,通过χ2 检验、AC值和Jaccard指数分别对青城山风景区森林植被乔木层11个常见种群和灌木层8个常见种群的种间联结进行定量分析,结果表明:W 检验说明青城山风景区森林乔木层常见种群与灌木层常见种群的总体种间关联性均... 详细信息

采用2×2列联表,通过χ2 检验、AC值和Jaccard指数分别对青城山风景区森林植被乔木层11个常见种群和灌木层8个常见种群的种间联结进行定量分析,结果表明:W 检验说明青城山风景区森林乔木层常见种群与灌木层常见种群的总体种间关联性均呈显著正相关;绝大多数种对是正联结,少部分种对是负联结,联结关系大多未达到显著水平,种对间的独立性相对较强,种间联结具明显的松散性.

关键词：青城山森林植被常见种群种间联结

Source-Sink Relationship in Intersubspecific Hybrid Rice

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Rice Science 2006年第4期 250-256页

作者： LI Ji-hang1, 2, 3. XIANG Xun-chao1, 2, 4, HE Li-bin1, 2, LI Ping1, 2 (1Rice Research institute, sichuan Agricultural University, Wenjiang 61113., China 2 Key Laboratory of Southwest Crop Genetic resource and Improvement, Ministry of Education, sichuan Agricultural University, Ya’an 625014, China 3.eneral Station of Agricultural Technology Extension in sichuan, chengdu 610041, China 4Southwest University of Science and Technology, Mianyang 621000, China)

Three indica restorer lines (Mianhui 725, Shuhui 527, Shuhui 881), an American rice variety Lemont and a javanica rice variety Xiangdali were crossed with japonica Kitaake, and five F1 hybrids were obtained to study the photosynthetic and agronomic traits. The data on photosynthetic characteristics indicated that the net photosynthetic rate (Pn) of the five F1 hybrids was significantly higher than that of their parents (or one of them) under high photosynthetic flux density (PFD); while the overall performance of hybrids was better than their respective parents in apparent quantum yield (AQY), carboxylation efficiency (CE) and CO2 compensation point (CCP). Moreover, the photosynthetic performance of the five F1 were different due to the variation in heredity and the typical indica-japonica hybrids, Mianhui 725/Kitaake and Shuhui 527/Kitaake, were better than the others on this aspect. The agronomic traits revealed that the five F1 exhibited different heterosis, with Shuhui 881/Kitaake the largest sink followed by Mianhui 725/Kitaake, Shuhui 527/Kitaake, Lemont/Kitaake and Xiangdali/Kitaake. The production potential of indica-japonica hybrids was higher than that of the other two hybrids, which was consistent with the performance of Pn. However, the superior trait of indica-japonica hybrids on sink size has not been fully turned into high yield because of abnormal seed setting. Therefore, attention should be paid to the proper genome coordination and appropriate genetic distance so as to achieve super high yielding.

关键词： rice intersubspecific hybrid source sink net photosynthetic rate genetic distance heterosis

Human activity response and prevention strategies on soil and water loss in sichuan Province

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Science China(Technological Sciences) 2003年第z1期46卷 91-109页

作者： FANG Yiping & CHEN Guojie institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water resources, chengdu 610041, China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water resources Chengdu 610041 Peoples R China

Ten major factors have been selected to judge the degree of disturbance from human activity and the corresponding relationship of the impact on soil and water loss in sichuan Province. Correlation analysis has demonstrated that stock-carrying capacity, percentage of land reclamation, population density, GDP per capita, mineral modulus and percentage of forest coverage are the 6 most relevant human activity factors. The analysis on the degree of disturbance has shown that population pressure, excessive or unreasonable activities in development of resources and destructive behavior of humans are the main causes of soil and water loss. Consequently, solving the various problems in the negative activity of humans and regulating human behavior are the first tasks that should be tackled in the conservation of water and soil. In the new era, the prevention and rectification of soil and water loss are measures based on the foundation of the ecosystem, which is a kind of {3. strategy for sustainable development. The foundation of this method is made up of the system innovations and breakthroughs in terms of aims, philosophy, measures, and aspects of the prevention and rectification of soil and water loss, simultaneous advance from the conceptual, policy, spatial, technical and mode levels and system integration on the treatment strategies.

关键词： sichuan, degree of disturbance, soil and water loss, system innovation.

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水资源系统工程的理论框架探讨

系统工程理论与实践 2004年第2期24卷 130-137页

作者：金菊良魏一鸣丁晶付强合肥工业大学土建学院安徽合肥230009 中国科学院科技政策与管理科学研究所北京100080 四川大学水电学院四川成都610065

　作为一门新兴交叉综合性工程技术学科,水资源系统工程在人口、资源、环境、经济与社会区域可持续发展战略研究中具有重要意义.根据水资源系统工程的基本概念,指出水资源系统工程的实质就是处理各种水资源系统问题的方法论,据此提出了... 详细信息

　作为一门新兴交叉综合性工程技术学科,水资源系统工程在人口、资源、环境、经济与社会区域可持续发展战略研究中具有重要意义.根据水资源系统工程的基本概念,指出水资源系统工程的实质就是处理各种水资源系统问题的方法论,据此提出了水资源系统工程新的理论框架,它由水资源系统优化方法、建模方法、预测方法、模拟方法、评价方法和决策分析方法组成.该理论框架在各种应用系统工程研究中具有参考应用价值.

关键词：水资源系统工程方法论理论框架

Soil Conservation Assessment in the Upper Yangtze River Basin Based on InVEST Model

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Soil Conservation Assessment in the Upper Yangtze River Basi...

Spatial Interpolation and Sample Size Optimization for Soil Copper(Cu) Investigation in Cropland Soil at County Scale Using Cokriging

2011 International Symposium on Water resource and Environmental Protection(ISWREP 2011)

作者： REN Jing Key laboratory of Mountain Hazards and Earth Surface Process, CAS, chengdu, sichuan 610041, China {3. of Mountain Hazards and Environment, CAS Graduate University of CAS, Beijing 100049, China.WANG Yukuan, FU Bin, XU Pei Key laboratory of Mountain Hazards and Earth Surface Process, CAS, chengdu, sichuan 610041, China {3. of Mountain Hazards and Environment, CAS chengdu, sichuan 610041, China

Studying and revealing the spatial distribution of soil loss will play an important role in water and soil conservation planning. In this study, the Geographic Information System （GIS） technology and the Integrated Valuation of Ecosystem Services and Tradeoffs Tool （InVEST） model were applied to estimate the amount of soil loss and assess the soil conservation capacity by the main ecological system in the Upper Yangtze River Basin （UYRB）. The results show: （1） the annual potential soil erosion is 92.92×10 8 t year -1 . The area of average annual soil loss bellow 500 km -2 year -1 occupies 3..08% and above 5000 km -2 year-1 occupies 3..8%. （2）The annual actual soil erosion is 12.3.×10 8 t year -1 . Slight and moderate soil loss is in majority, about 68.15% of the watershed area is found out to be under moderate degree. （3.The annual soil conservation is 80.61×10 8 t year -1 , and the contributing percent of main individual ecosystems was as follows: the forest occupies 46.11%, grassland 24.21%. Forest ecosystem does best in soil conservation.

关键词： The Upper Yangtze River Basin (UYRB) USLE GIS Soil erosion Soil Conservation

来源： cnki会议评论

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Agricultural Sciences in China 2009年第11期8卷 1369-1377页

作者： PANG Su,LI Ting-xuan,WANG Yong-dong,YU Hai-ying and LI Xi College of resource and Environmental Science,sichuan Agricultural University,Ya’an 625014,P.R.China [a]College of resource and Environmental Science Sichuan Agricultural University Ya'an 625014 P.R. China

Knowledge on spatial distribution and sampling size optimization of soil copper （Cu） could lay solid foundations for environmetal quality survey of agricultural soils at county scale. In this investigation, cokriging method was used to conduct the interpolation of Cu concentraiton in cropland soil in Shuangliu County, sichuan Province, China. Based on the original 623.physicochmically measured soil samples, 560, 498, and 43. sub-samples were randomly selected as target variable and soil organic matter （SOM） of the whole original samples as auxiliary variable. Interpolation results using Cokriging under different sampling numbers were evaluated for their applicability in estimating the spatial distribution of soil Cu at county sacle. The results showed that the root mean square error （RMSE） produced by Cokriging decreased from 0.9 to 7.77%, correlation coefficient between the predicted values and the measured increased from 1.76 to 9.76% in comparison with the ordinary Kriging under the corresponding sample sizes. The prediction accuracy using Cokriging was still higher than original 623.data using ordinary Kriging even as sample size reduced 10%, and their interpolation maps were highly in agreement. Therefore, Cokriging was proven to be a more accurate and economic method which could provide more information and benefit for the studies on spatial distribution of soil pollutants at county scale.

关键词： cropland soil county scale copper Cokriging sampling size

The tautomerization of H_2NCH_2C(OH)NH to H_2NCH_2CONH_2 in the interstellar medium

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 156-163页

作者： XU sichuan DENG ShengRong MA LiYing SHI Qiang ZHANG XingKang GE MaoFa Key Laboratory of Ministry of Education for Medicinal Chemistry of Natural resource College of Chemical Science and Technology Laboratory on the Origin of Life Yunnan University Kunming 650091 China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The tautomerization of H2NCH2C(OH)NH to H2NCH2CONH2 is an important step by way of Strecker synthesis for the production of glycine in the interstellar medium (ISM) with respect to the origin of amino acids on the early *** work indicates two mechanisms for the tautomerization to occur.k CVT/SCT (rate constant) is 45.6s-1 at 50 K,obtained with the small curvature tunneling (SCT) approximation and canonical variational transition state theory (CVT),to support one mechanism assisted by quantum tunneling in the *** mechanism is through the (H2O) 2-coupled proton *** the (H2O)2 coupled reaction,two H2O molecules act as a catalyst to reduce the barrier energy by 23.7 kcal mol 1,and cooperatively let a proton pass a hydrogen-bonded bridge composed of H2NCH2C(OH)NH with (H2O)*** is 8.08×10-4 s-1 at 100 K,calculated with TST kinetics,to demonstrate the ***,the tautomerization is feasible in the ISM.H2NCH2C(OH)NH and H2NCH2CONH2 will be detected in the ISM and found in carbonaceous *** results present new evidence for the third theory on the origin of amino acids on the early Earth.

关键词： H2NCH2C(OH)NH H2NCH2CONH2 interstellar medium amino acid origin hydrogen tunneling