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Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest china

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Progress in Natural Science:Materials International 2009年第3期19卷 337-346页

作者： Yuhong Wu a, Qingnian Cai b, Chaowen Lin c, Yibing Chenc, Yuying Lid, Xu Cheng b,* a college of resources and environmental Sciences, china Agricultural university, beijing 100193, china b college of Agriculture and Biotechnology, china Agricultural university, beijing 100193, china c Institute of Soils and Fertilizers, Sichuan Academy of Agricultural Sciences, Chengdu 610066, china d college of Life Science and Technology, Nanyang normal university, Nanyang 473061, china [a]college of resources and environmental Sciences China Agricultural University Beijing 100193 China [b]College of Agriculture and Biotechnology China Agricultural University Beijing 100193 China [c]Institute of Soils and Fertilizers Sichuan Academy of Agricultural Sciences Chengdu 610066 China [d]College of Life Science and Technology Nanyang Normal University Nanyang 473061 China

Spiders are important predators in agroecosystems and contribute to the control of agricultural pest populations. Habitat manage- ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity. Using pitfall traps, we investigated the effects of four hedgerow plant species, which serve as undisturbed and permanent semi-natural habitats, on ground-dwelling spider activity density (a parameter of population density and relative activity) and species richness. Samples were collected over two winter wheat and two summer maize growing seasons during 2005-2007 in trial field 1 (slope gradient of 20%) and field 2 (slope gradient of 12%) at the Ziyang Experimental Site in Sichuan Province, china. The hedgerow species evaluated were Amorpha fruticosa (field 1), Vetiveria zizanioides (field 1), Eulaliopsis binata (field 2), and Medicago sativa (field 2). Compared to control plots, hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season. The presence of hedgerow strips did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons. The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the Amorpha plots and in the Medicago than in the Eulaliopsis plots, and the species richness was significantly higher in the Vetiveria than in the Amorpha plots during the wheat season. Our results suggest that hedgerows may serve as important overwintering sites for ground-dwelling spiders during the wheat growing season. In addition, the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas. However, ground-dwelling spiders did not move into adjacent crop fields; the

关键词： Activity density Araneae Ground-dwelling Hedgerow Pitfall trapping Species richness

Mutual Conversion of Land Use between Urban and Rural Area in the Process of Urbanization: A Case Study of Shandong Province

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Chinese Journal of Population,resources and environment 2007年第2期5卷 93-96页

作者： Xu Hong college of Population, Resource and environment, Shandong normal university, Jinan Shandong 250014, china college of Population Resource and environment Shandong Normal University Jinan Shandong 250014 China

Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization.

关键词： mutual conversion of land use between urban and rural areas structure of land use flow of the cultivated land

Characteristics of energy dissipation in hyperconcentrated flows

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International Journal of Sediment Research 2008年第4期23卷 387-397页

作者： An-ping SHU 1,Qing-quan LIU2,Yu-jun YI 3,and Zhi-dong ZHANG 41 Assoc.Prof.,School of environment,Key Laboratory of Water and Sediment Sciences of Ministry of Education,beijing normal university,beijing 100875,china2 Prof.,Institute of Mechanics,Chinese Academy of Sciences,beijing 100080,china3 Lecturer,Dr.,School of environment,beijing normal university,beijing 100875,china4 Graduate student,School of environment,beijing normal university,beijing 100875,china [a]Assoc. Prof. School of environment Key Laboratory of Water and Sediment Sciences of Ministry of Education beijing normal university beijing 100875 china [b]Prof. Institute of Mechanics Chinese Academy of Sciences beijing 100080 china [c]Lecturer Dr. School of environment beijing normal university beijing 100875 china. The project is supported by the National Natural Science Foundation of china (Grant No. 10672024) [d]Graduate student School of environment beijing normal university beijing 100875 china

An equilibrium equation for the turbulence energy in sediment-laden flows was derived on the basis of solid–liquid two-phase flow theory. The equation was simplified for two-dimensional, uniform, steady and fully developed turbulent hyperconcentrated flows. An energy efficiency coefficient of suspended-load motion was obtained from the turbulence energy equation, which is defined as the ratio of the sediment suspension energy to the turbulence energy of the sediment-laden flows. Laboratory experiments were conducted to investigate the characteristics of energy dissipation in hyperconcentrated flows. A total of 115 experimental runs were carried out, comprising 70 runs with natural sediments and 45 runs with cinder powder. Effects of sediment concentration on sediment suspension energy and flow resistance were analyzed and the relation between the energy efficiency coefficient of suspended-load motion and sediment concentration was established on the basis of experimental data. Furthermore, the characteristics of energy dissipation in hyperconcentrated flows were identified and described. It was found that the high sediment concentration does not increase the energy dissipation; on the contrary, it decreases flow resistance.

关键词： Hyperconcentrated flows Turbulence energy Efficiency coefficient Energy dissipation

MAPK signal pathways in the regulation of cell proliferation in mammalian cells

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Cell Research 2002年第1期12卷 9-18页

作者： WEI ZHANG, Hui Tu LIU The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, college of Life Sciences, beijing normal university, beijing 100875, china 1The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education College of Life Sciences Beijing Normal University Beijing 100875 China 1The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education College of Life Sciences Beijing Normal University Beijing 100875 China

MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.

关键词： MAPK ER.K JNK/SPAK p38 cell proliferation cross-talk.

environmental　risk　assessment　of　the　middle　route　of　south－to－north　water　transferring　source　project　in　china

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Journal of environmental Sciences 1996年第3期8卷 285-291页

作者： Wang Huadong Wang Fei(Institute of environmental Sciences,beijing normal university, beijing 100875, china) Institute of environmental Sciences Beijing Normal University Beijing 100875 China

This paper focused on the environment risk of the middle route of south-to-north water transferring source project in china. Analytic hierarchy process was applied to risk identification,fuzzy probability-fault tree analysis to risk probability assessment,statistics and analogy process to risk consequences assessment, lastly, grey relevant analysis and comprehensive index process to risk impact evaluation. The main environment risk accident of the project is dam failure, the main causative factors of the accident are catastrophic flood and wrecking earthquake. The flash flood, due to dam failure, will impact on nature, society and economy. The major environment risk areas are Jingzhou and Xiangfan,Hubei Province. The environment risk management measures should be adopted in order to ensure the safety of the project-environment complex system.

关键词： water source project environment risk risk assessment

Effects of chronic exposure to nonylphenol on locomotor activity and social behavior in zebrafish(Danio rerio)

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Journal of environmental Sciences 2010年第9期22卷 1435-1440页

作者： Jigang Xia,Cuijuan Niu ,Xuejiao Pei Ministry of Education Key Laboratory of Biodiversity Science and Ecological Engineering,college of Life Sciences,beijing normal university,100875 beijing,china. [a] Ministry of Education Key Laboratory of Biodiversity Science Ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing China

Nonylphenol （NP）, a xenoestrogen ubiquitously found in aquatic ecosystems, is of high environmental concern. The present work assessed the effects of exposure to NP on locomotor activity and social behavior in male and female zebrafish （Danio rerio）, to evaluate the possible hazard of NP to fish behavior and to pursue a potential biomarker of NP contamination. Fish were randomly divided into six groups. Five groups were receiving 0.1, 1, 10, 50 and 100 μg/L nominal concentrations of NP for 60 days, respectively. A sixth control group was given the same treatment as the other five groups, but no NP. Locomotor activity, aggressive behavior, group preference and leaving shoal were examined. NP exposure showed marked influence on locomotor activity of the male zebrafish, whereas that of the female was not significantly affected by NP. Aggressive behavior and group preference were significantly affected by NP exposure in both male and female groups. Locomotor activity and aggressive behavior of the male and group preference of both male and female zebrafish were clearly inhibited at 100 μg/L NP. No significant alteration in leaving shoal was observed under NP exposure. The results suggested that changes in locomotor activity and aggressive behavior of the male and group preference of both male and female may be used as an ecologically relevant integrative biomarker of NP contamination.

关键词： chronic toxicity nonylphenol biomarker zebrafish

A HIGH-ORDER-ACCURATE DIFFERENCE SCHEME WITH UNCONDITIONAL STABILITY FOR THE DIFFUSION EQUATION ON NONUNIFORM GRIDS

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Journal of Hydrodynamics 2001年第1期13卷 92-98页

作者： Wang Xuan, Yang Zhi-feng State Key Laboratory of environment Simulation and Pollution Control, Institute of environmental Sciences, beijing normal university, beijing 100875, china[WT5”HZ] beijing normal Univ. Beijing 100875 China

WT5”BZ]A high-order-accurate difference scheme with unconditional stability is developed for the diffusion equation on nonuniform grids. The theoretical analysis shows that the accuracy of this scheme is between third order and fourth order, and fourth-order accuracy is achieved in the case of the same grid steps being used within the computational domain. Two numerical examples are given to demonst ate the advantages of the proposed scheme. Compared with the conventional difference scheme, more accurate numerical solution can be obtained by using the proposed scheme even with relatively larger grid sizes. It is also pointed out that the appropriate structure of the nonuniform grid can not only make the proposed scheme more practical, but lead to a solution superior to that for a uniform grid structure. [WT5”HZ]

关键词： ]finite difference scheme diffusion equation nonuniform grid high accuracy computational fluid dynamics

Land Use/Land Cover Change(LUCC) and Eco-environment Response to LUCC in Farming-Pastoral Zone,china

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Agricultural Sciences in china 2009年第1期8卷 91-97页

作者： HAO Hui-mei and REN Zhi-yuan college of tourism and environmental Science,Shaanxi normal university,Xi’an 710062,P.R.china [a]college of tourism and environmental Science Shaanxi Normal University Xi'an 710062 P. R. China

In order to understand land use/land cover changes （LUCC） and the eco-environment response to LUCC in farming- pastoral zone of the northern china during the recent twenty years, Baotou prefecture was selected as a case study area for investigation and quantitative evaluation. Technologies of remote sensing （RS）, global positioning system （GPS）, geographic information system （GIS）, and other statistical methods were employed to implement. Results showed that：（1） During the recent twenty years, the areas of forest lands, grasslands and water were reduced, whereas the areas of other types were enlarged. Parts of forest lands, grasslands, and waters had become farmlands, and about 31.5% of the changed grasslands transferred into unused lands. The newly increased farmlands mainly came from grasslands and unused lands. And the newly increased construction lands mainly came from grasslands and farmlands. （2） Regional eco- environmental quality decreased by 12.6%, for which the land degradation （especially the meadow degeneration） and the developing of the cultivated land were mainly responsible, and their contributions to the regional eco-environment changes were 51.84 and 23.63% respectively. （3） The tendency of LUCC and the eco-environment response to LUCC displayed spatial heterogeneity. It can be concluded that the present agricultural production mode was not sustainable in farming-pastoral zone of northern china. Land degradation, especially meadow degradation induced by over-trampling and overgrazing, and developing of cultivated land were mainly responsible for regional eco-environment deterioration. Changing the cultivated land to forest or grass, however, can relieve deterioration of local eco-environment to some extents. And in the farming-pastoral zone in the northern china, evaluating regional eco-environment responses to LUCC was very necessary due to its fragile eco-environments.

关键词： farming-pastoral zone LUCC eco-environment responses to LUCC

Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore-hosting dolomite rocks in the middle Kunyang rift, central Yunnan, china

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Progress in Natural Science:Materials International 2008年第8期18卷 965-974页

作者： Yongbei Zhanga,b,c, Hua Bia,*, Longshi Yua, Shihua Sunc, Jiaxiang Qiub, Chengyan Xub, Hao Wang b, Renjing Wang b a The Department of resources, environment and tourism, Hainan normal university, No. 432, Yinpo Road, Longshepo, Haikou 57000, china b Key Laboratory of Mineral resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china c Faculty of Earth Sciences, china university of Geosciences, Wuhan 470074, china The Department of resources Environment and Tourism Hainan Normal University No. 432 Yinpo Road Longshepo Haikou 57000 China Key Laboratory of Mineral resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Faculty of Earth Sciences China University of Geosciences Wuhan 470074 China

The Kunyang rift lying on the western margin of the Yangtze platform is a rare Precambrian Fe-Cu mineralization zone. WudingLufeng basin that is an important part of the zone is located on the west edge in the middle of the rift. The most important ore-hosting rocks are Mesoproterozoic dolomite rocks in the basin controlled by a ring fracture system, which is a fundamental structure of the basin. Plenty of silicate minerals and acicular apatite, feldspar phenocrysts and small vesicular, flown line and flown plane structures, melt inclusion and high temperature fluid inclusion found in most ore-hosting dolomites suggest that this kind of rocks could not be sedimentary dolomite, marble or hydrothermal carbonate rocks. The Zr/Hf and Nb/Ta values of the rocks are identical with those of associated mantle-derived rocks, and vary widely. For the monomineral dolomite, d18OSMOW‰ = +5.99 to +18.4 and d13CPDB‰ = à3.01 to +0.94, which fall within the range for all carbonatitic volcanic rocks of the world. As for the accessory minerals, the values of d18OSMOW‰ of magnetite (=+3.47 to +5.99‰) are close to that of the mantle (<5.7%), and the d34S‰ values of sul?des (à5.09 to +5.78, averaging +1.50) are close to that of meteorite. For all the ore-bearing dolomite rocks, eNd = +0.19 to +2.27, and the calculated ISr = 0.699143, while for the associated mantle-derived rocks, eNd = +3.18 to +3.72. All the data suggest that the mineral assemblage is not only igneous but also of metasomatic mantle origin. And the presence of acicular apatite indicates that the rocks were formed by magma rapidly cooling. And the phenocryst texture and vesicular, flown and ropy and pyroclastic structures suggest that the igneous rocks were extrusive. Therefore, the ore-bearing dolomite rocks are carbonatitic volcanic rocks. This conclusion implies that most iron and copper ore deposits hosted in the dolomite rocks should be of the carbonatite type.

关键词： Central Yunnan Kunyang rift Precambrian Mineralization Carbonatitite Volcanic rocks Petrogenesis Iron and copper ore deposit