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Process and mechanism of arable land change in Hebei Province during the past 50 years

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Journal of Geographical Sciences 2001年第4期11卷 47-52页

作者： XU Yue-qing (Institute of Geographical Sciences and Natural resources Research, CAS, beijing 100101, china {3. of Resource and {4. Science, Hebei normal university, Shijiazhuang 050016, china ) CAS Institute of Geographical Sciences and Natural Resources Research Beijing China (GRID:grid.9227.e) (ISNI:***) Hebei normal university College of Resource and Environment Science Shijiazhuang China (GRID:grid.256884.5) (ISNI:***)

Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in china. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable *** paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 4..22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc.

关键词： decrease in arable land area changing process mechanism Hebei Province

Thresholds of geographic environmental elements in sediment yield of drainage basins

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Science china Earth Sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan Institute of Geographic Sciences and Natural resources Research, Chinese Academy of Sciences, beijing 100101, china Institute of Forestry Science, Chinese Academy of Forestry Science, beijing 100091, china Research Center for Eco-environment Sciences, Chinese Academy of Sciences, beijing 100085, china Computing Institute of Science and Engineering, North china Electric Power university, beijing 102206, china 1. Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Science Chinese Academy of Forestry Science 100091 Beijing China 3. Research Center for Eco-environment Sciences Chinese Academy of Sciences 100085 Beijing China 4. Computing Institute of Science and Engineering North China Electric Power University 102206 Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

Spatio-temporal carbon isotope variation during the Ediacaran period in South china and its impact on bio-evolution

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Science china Earth Sciences 2009年第10期52卷 1520-1528页

作者： WANG XinQiang1 & SHI XiaoYing1,2 1 School of Earth Science and Mineral resources, china university of Geosciences, {3. 100083. china 2 State Key Laboratory of Geological Processes and Mineral resources, {3. 100083. china School of Earth Science and Mineral resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and Mineral resources Beijing 100083 China

The Ediacaran period is characterized by the extremely negative carbon isotope anomalies and great biotic evolution in Earth history. At least four negative carbon isotope anomalies have been reported from this interval in South china so far. It is traditionally argued that the isotope variations can be used as a useful tool for global correlation of Ediacaran succession; however, more and more researches argued against this idea. We reviewed the previously published carbon isotope data in South china, and distributed the mean values of a certain time to the paleogeographic maps. The results show that the carbon isotope values (δ13.) vary greatly in different environments, but a clear tendency of becoming lighter from shallow platform to deep basin, with a maximum variation up to 1‰ Moreover, the important changes in Ediacaran biota, marked by the introducing of new taxa or ecologic groups, seemed to always postdate the negative anomalies but coincide with the positive shift. If the negative excursions represented the oxidation of a large dissolved organic carbon (DOC) reservoir in the ocean, the diverse Ediacaran organisms and the carbon isotope anomalies may suggest totally different environments: oxic and anoxic/euxinic. We also suggest that the elimination of euxinic state through precipitation of pyrites is one of the important environment factors in prompting the Ediacaran bio-evolution.

关键词： Ediacaran South china carbon isotope spatio-temporal variations bio-evolution

Development of tourism resources and environment conservation in china: with special reference to Taishan Mountain

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Journal of environmental Sciences 1991年第3期3卷 99-104页

作者： Liu JihanDepartment of Geography,Peking university,beijing 100871,china

By analyzing the cases in Taishan Mountain, Shandong Province and other tourist sites in china, this paper pointed out the problems in tourism management, such as resources damage, environment pollution, which are the result of tourism development, and are obstacles to the development. The paper also gave suggestion and practical ways to preserve tourism resources and environment.

关键词： tourism resources environment conservation Taishan Mountain tourism development.

Research on the damage of the Great Wall of Ming Dynasty in beijing by remote sensing

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Science china(Technological Sciences) 2008年第S1期51卷 195-202页

作者： LI XiaoJuan,GONG HuiLi,ZHANG Ou,ZHANG WeiGuang & SUN YongHua The Key Lab of 3. Information Acquisition and Application,MOE,the Key Lab of beijing Resource Envi-ronment and GIS,and college of Resource environment & Tourism,Capital {3. university,beijing 10003.,china Capital normal Univ Key Lab Informat Acquisit & Applicat MOE Key Lab Beijing Resource Environm Beijing 100037 Peoples R China

Using aerial photos and high resolution satellite images of the year of 2004.this paper establishes remote sensing interpretation marks of the Great Wall of Ming Dynasty's damaged levels. Based on field survey and remote sensing survey in 1984.we analyzed present situation and changing characteristics being of the Great Wall of Ming Dynasty in beijing. The results show that about 7.02% of the wall is well-preserved (about 25861 m); 3..5% of the wall is slightly or moderately dam-aged (about 115989 m); 61.5% of the wall is badly damaged (about 2263.9 m). This paper analyzes the dynamic change of the Great Wall of Ming Dynasty. It shows that the damaged situation of the Great Wall of Ming Dynasty in beijing is serious. From 1984.to 2004.the well-preserved wall is decreased by 3.206 m (decreased by 56%); badly damaged wall increased by 51207 m (increased by 67%). Finally,this paper analyzes the influence factors of damaging Great Wall. The conclusion is as follows: The damaged Great Wall is generally near the roads and villages,small slope,and easily arriving land.

关键词： the Great Wall of Ming Dynasty remote sensing interpreting damage dynamic change spatial analysis

Arable land increase in northern china: facts and findings

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Journal of Geographical Sciences 2002年第1期12卷 108-113页

作者： SONG Jin-ping1, LI Xiu-zhen2 (1. Dept. of resources and environment, beijing {3. {4., beijing 100875, china 2. Institute of Applied Ecology, CAS, Shenyang 110015, china) Dept. of resources and environment Beijing Nonnal University 北京 100875 Institute of Applied Ecology CAS Shenyang 110015

Based on investigations between 1986 and 1996 in the four provinces of northern china, major problems on land reclamation were discovered. The increase of arable land was mainly low quality fields from barren land and was susceptible to disertification and water-induced soil erosion. In the meantime, large area of grassland and forestland was lost or degraded, and original fertile arable land was occupied for residential and industrial use. As a result the environment deteriorated. This change was mainly caused by economic development, population growth, inferior natural conditions, and irrational management strategies. Finally some positive measures were suggested to stop this negative cycle.

关键词： arable land reclamation land resources land quality

Three industries and water consumption of beijing

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Journal of environmental Sciences 1998年第2期10卷 54-61页

作者： Wang Hong rui Institute of environmental Sciences,beijing normal {3.,beijing 100875,china Wang Yan beijing Municipal Research Institute of environmental Protection,beijing 10003.,china

beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of the municipal water use structure and its changes in the industrial sectors were analysed and discussed in terms of the indicators, such as direct water use coefficient, complete water use coefficient, water use multiplier and water reuse rate, by taking a year of 1990s as the base year. Some response strategies for water conservation have been studied and the corresponding recommendations were put forward. All of these have provided a basis for coordinating the relationship between aquatic environment and economic growth in this city, establishing a system for rational utilization of water resources, and promoting the implementation of a strategy for sustainable development.

关键词： direct water use coefficient complete water use coefficient water use multiplier water reuse rate.

Root Growth Potential and Energy Sources for New Root Growth of Three Conifer Species in Northern china

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北京林业大学学报 1993年第S3期 10-22页

作者： Liu Yong Forest resources college,beijing Forestry {3.

Seedlings of Pinus sylvestris var. mongolica, Larix principis—rupprechtii and Platycladus orientaliswere lifted from the nursery in March and transplanted to favorable growing conditions in a controlledenvironment chamber. The test of RGP showed that Platycladus orientalis seedlings had the greatest RGP amongthe three species, any one of the four parameters as TNR, TNR>1, TLR>1 and SAI could representthe RGP of Platycladus orientalis. However, at least two parameters (TNR and any one of TNR>1,TLR>1, SAI)must be used to represent the RGP of Larix principis—rupprechtii and Pinus sylvestris *** seedlings due to the weak correlation between root initiation and root elongation for the twospecies. The results of the RGP test and carbohydrate analysis for different treatments demonstrated thatcurrent photosynthate is needed for new root growth in Pinus sylvestris var. mongolica seedlings, whereasstored-carbohydrates provided the energy source for new root initiation. Current photosynthate is also neededfor root elongation in Larix principis — rupprechtii seedlings; New root growth of Platycladus orientalisseedlings is primarily caused by current photosynthate, but some reserve materials may be utilized at thesame time if photosynthesis is inadequate to meet growth demands.

关键词： root growth potential(RGP) current photosynthate stored carbohydrates

TECC Applied in Geopark for a Case Study of Qixia Planning National Geopark

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地学前缘 2009年第S1期16卷 295-296页

作者： Feifei Hu,Mingzhong Tian School of the Earth Sciences and resources,china university of Geosciences({3.),{3. 100083.china.

This paper applied the theory of TECC(Tourism environmental Carrying Capacity) into the case of Qixia Planning National *** adopt new planning framework to do the planning of TECC。

关键词： TECC geoheritages basic environment Qixia Planning National Geopark