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LANDSCAPE ECOLOGICAL CONSTRUCTION IN RURAL china:THEORY AND APPLICATION

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chinese Geographical Science 2001年第2期11卷 104-114页

作者： XIAO Du-ning (cold and {1. {2. environmental and engineering research Institute, the chinese academy of sciences, lanzhou 730000, P.R.china Institute of Applied Ecology,the chinese academy of sciences, Shenyang 1.001.,P.R.china ) cold and {1. {2. environmental and engineering research Institute the Chinese Academy of Sciences Lanzhou P.R. China Institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

In landscape with overpopulation, intensive management for economic production, and where even small natural-vegetation patches are scarce, ecological conservation generally must be developed in the course of economic development. Thus “landscape ecological construction” has evolved in china. This approach adds spatial elements and alters landscape pattern to strengthen inter-ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. Five examples of managed landscapes in china are presented: dike-pond systems in a river delta; multi-pond system in a rice paddy landscape; field-grass-wood grid system on unstable sand dunes; shelterbelt network in a crop field area; and field-grass-wood mosaic system on highly erodible hilly farmland. These indicate that ecological conditions can be improved along with increased economic production. Altering landscape structure and ecological flows by introducing small landscape elements in distinct spatial patterns is considered a key to the results. This reshaping of the land has focused on changing patch size, regularity of arrangement, biological and hydrological corridors, and networks, the matrix and grain size. It suggests that such changes can increase negative feedbacks and increase stability. Finally, planning and design principles are pinpointed for the landscape ecological construction process.

关键词： landscape planning ecological construction rural china

Vicissitude of Sogo Nur and environmental-climatic change during last 1.00 years

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Science china Earth {1. 2004年第z1期47卷 61-70页

作者： JIN Heling, XIAO Honglang, SUN Liangying, ZHANG Hong, SUN Zhong & LI XiaozeKey Laboratory of Desert and Desertification, cold and {1. {2. environmental and engineering research Institute, chinese academy of sciences, lanzhou 730000, china School of Resources and Environment, lanzhou University, lanzhou 730000, china 1. Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China2. School of Resources and Environment Lanzhou University 730000 Lanzhou China

Lakes in arid zone are sensitive to climatic changes. The lacustrine sediment sequence in Sogo Nur has well and truly recorded climatic events such as the Sui-Tang Dynasty Warm Period, the Song-Liao Dynasty {1. Period, the Medieval Warm Period, the Little Ice Age and the 2.th Century Warm Period. Commonly, the climate in warm Periods was relatively humid,accordingly the lake area extended and water level rose, and vice versa. Apart from climatic change, human activity is also an important factor of influencing lake vicissitude, and they played the dominant role alternatively during different periods; the factor of climatic change predominated in historical period, while since the beginning of the 2.th century the utilization of water resources by human has became decisive.

关键词： granularity, soluble salt, lake vicissitude, climatic change, Sogo Nur.

Magnetic characteristics of dustfall in urban area of north china and its {1. significance

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Science china Earth {1. 2007年第11期50卷 1724-1732页

作者： XIA DunSheng1,2. YANG LiPing2. MA JianYing1, YU Ye1, WANG Guan2.& CHEN FaHu2.1 Key Laboratory of Desert and Desertification, Institute of cold and arid {2. environmental and engineering, chinese academy of sciences, lanzhou 730000, china 2.CAEP, Key Laboratory of West china’s environmental System (Ministry of Education), lanzhou University, lanzhou 730000, china 1. Key Laboratory of Desert and Desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou 730000 China 2. CAEP Key Laboratory of West China’s Environmental System (Ministry of Education) Lanzhou University Lanzhou 730000 China

Urban particulate pollutants not only affect urban air quality but also directly threaten public health. lanzhou has been one of the most seriously polluted cities in the world due to its special geophysical location and weather conditions, which makes it an ideal place for urban particulate pollution study. In this study a set of {1. magnetic parameters (χ_(1.),χ_(fd)%, χ_(ARM), SIRM, HIRM, SOFT and back field IRM) were measured and analyzed for the dustfall samples collected monthly during 1.97.4—2.00.5 and 2.04.1.—2.05.1. at lanzhou University campus (KLD and CCS) and at a clear site of Gaolanxian (GLX). Results demonstrate that the main magnetic minerals in the dustfall are magnetite, with some maghaemite and haematite. Cross plots of M_(rs)/M_s vs. B_(cr)/B_c and χ_(fd)% vs. χ_(ARM)/SIRM indicate that the main magnetic grain sizes are pseudo-single-domain (PSD). The high concentration of magnetic minerals in the dustfall indicates that lanzhou is seriously polluted. The main pollution sources are anthropogenic activities and nature dust, with the former posing a great threat during the whole year, which is different from the general view that the natural dust is the main contributor in summer. With great efforts of the government and local authority in the past decades, the air quality in lanzhou has been improved in winter, but it is not so obvious in summer. This study also reveals that as a simple, rapid and accurate technology, {1. magnetism could be a valuable tool for urban pollution study.

关键词： environmental magnetism,dustfall,air pollution,lanzhou

Stochastic modelling of soil moisture dynamics in a grassland of Qilian Mountain at point scale

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Science china Earth {1. 2007年第12期50卷 1844-1856页

作者： LIU Hu,ZHAO WenZhi HE ZhiBin & ZHANG LiJie Linze Inland River Basin research Station,chinese Ecosystem research Network Laboratory of Watershed Hydrology and Ecol-ogy,cold and arid regions environmental and engineering research Institute,chinese academy of sciences,{12. 730000,china 1. Linze Inland River Basin research Station Chinese Ecosystem Research Network China 2. Laboratory of Watershed Hydrology and Ecology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Stochastic modeling of soil moisture dynamics is crucial to the quantitative understanding of plant responses to water stresses,hydrological control of nutrient cycling processes,water competition among plants,and some other ecological dynamics,and thus has become a hotspot in ecohydrology at *** this paper,we based on the continuously monitored data of soil moisture during 2.02.2.05 and daily precipitation date of 1.92.2.06,and tried to make a probabilistic analysis of soil moisture dynamics at point scale in a grassland of Qilian Mountain by integrating the stochastic model improved by Laio and the Monte Carlo *** results show that the inter-annual variations for the soil moisture patterns at different depths are very significant,and that the coefficient of variance(CV) of surface soil moisture(2. cm) is almost continually kept at about 0.2. whether in the rich or poor rainy ***,it has been found that the maximal CV of soil moisture has not always appeared at the surface *** of the analytically derived soil moisture probability density function(PDF) with the statistical distribution of the observed soil moisture data suggests that the stochastic model can reasonably describe and predict the soil moisture dynamics of the grassland in Qilian Mountain at point *** extracting the statistical information of the historical precipitation data in 1.94―2.06,and inputting them into the stochastic model,we analytically derived the long-term soil moisture PDF without considering the inter-annual climate fluctuations,and then numerically derived the one when considering the inter-annual fluctuation effects in combination with a Monte-Carlo *** was found that,though the peak position of the probability density distribution significantly moved towards drought when considering the disturbance forces,and its width was narrowed,accordingly its peak value was increased,no significant bimodality was observed in the soil moistur

关键词： soil moisture dynamics, stochastic modelling, Monte Carlo method, probability density function, grassland ecosystem

Cooling effect of ripped-stone embankments on Qing-Tibet railway under climatic warming

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Science Bulletin 2003年第6期48卷 598-604页

作者： LAI Yuanming1, ZHANG Luxin1 , ZHANG Shujuan1 & MI Long2.1. State Key Lab. of Frozen Soil engineering, cold and {2. regions environmental and engineering research Institute, chinese academy of sciences, lanzhou 730000, china 2. Department of Civil engineering, Northern Jiaotong University, Beijing 100044, china State Key Lab. of Frozen Soil engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Department of Civil engineering Northern Jiaotong University Beijing China

The heat convection in ballast mass and ripped-stone mass in railway embankments is the problem of heat convection in porous media. In order to calculate the temperature distribution of Qing-Tibet railway embankment, from the governing equations used to study forced convec-tion for incompressible fluids porous media, the finite ele-ment formulae for heat convection in porous media are de-rived by using Galerkin抯 method. The temperature fields of the traditional ballast embankment and the ripped-stone mass embankment, constructed on July 1., have been ana-lyzed and compared under the case that the air temperature in Qinghai-Tibetan Plateau will be warmed up by 2.0℃ in the future 50 years. The calculated results indicate that, the permafrost 5 m below the traditional ballast embankment will be thawed in the {1. in which the air yearly-average temperature is larger than -3.5℃ or the yearly-average temperature at the native surface is larger than -1.. The embankment will cause large thawing settlement. The rail-way embankment will be damaged by permafrost degrada-tion. The ripped-stone mass embankment can not only resist the effect of climatic warm up on it but also provide cool energy for the permafrost under it. It can assure permafrost stability and not subjected to thawing. Therefore, it is highly recommended that the ripped-stone mass embankment be taken as the Qing-Tibet railway embankment structure in high-temperature permafrost {1. so that permafrost embankment can be protected as possible as we could.

关键词： cooling effect ripped-stone embankment climatic warming.

Variations of δ^(1.)O in precipitation from the Muztagata Glacier, East Pamirs

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Science china Earth {1. 2006年第1期49卷 36-42页

作者： LI Zhen1, YAO Tandong1,2. TIAN Lide1,2. XU Baiqing1,2.& Wu Guangjian2.1. Key Laboratory of Cryosphere and Environment, Jointly Established by cold and arid {2. environmental and Engi-neering research Institute and Institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, CAS, lanzhou 730000, china 2. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china 1. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China 2. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Expeditions to Muztagata (in the eastern Pamirs) during the summer seasons of2.02.and 2.03 collected precipitation samples and measured their oxygen isotopes. The δ^(1.)O inprecipitation displays a wide range, varying from -1..40per thousand to +1.33per thousand inJune—September 2.02.and from -2..31.er thousand to +4.59per thousand in May—August 2.03. Theδ^(1.)O in precipitation correlates with the initial temperature of precipitation during theobserving periods. The positive correlation between δ^(1.)O and temperature suggests that δ^(1.)Ocan be used as an indicator of temperature in this region. The δ^(1.)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztagata Glacier show a strong''altitude effect'', with a ratio of nearly -0.40per thousand per 1.0 m from 5500 m to 7450 m.

关键词： Muztagata, δ1.O, temperature, altitude effect.

Variations of near-surface atmospheric CO_(2.and H_(2.O concentrations during summer on Muztagata

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Science china Earth {1. 2006年第1期49卷 18-26页

作者： XU Baiqing1,2. YAO Tandong1,2. LU Anxin2. GUO Xuejun, LIU Xianqin2.& LI Zhen2.1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085,{2. 2. Key Laboratory of Cryosphere and Environment, Jointly Established by cold and arid regions environmental and Engi-neering research Institute and Institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological {12.,{2. Meteorological Administration, lanzhou 730000,{2. 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Expeditions during the summers of 2.02.and 2.03 implemented continuous monitoring of near-surface (2.m height) atmospheric CO2.and H2. concentrations at the 4500 m elevation on Muztagata. The resultant data sets reveal a slight decrease of CO2.concentrations (of about 5 μmol·mol?1. and changes in the diurnal variations from the end of June to the middle August. The daily maximum CO2.concentrations occur between 02.30―05:30 AM (local time) and the minimum levels occur between 1.0}00―1.:30 PM. The atmospheric CO2.concentrations in the summer of 2.02.were around 5 μmol·mol?1.lower than those during the same period of 2.03, whereas the diurnal amplitude was higher. In contrast, we found that the daily mean atmospheric H2. content in 2.03 was much lower than that in 2.02.and there exists a striking negative correlation between CO2.and H2. con-centrations. We therefore suggest that the near-surface atmospheric CO2.concentration is affected not only by photosynthesis and respiration, but also by the air H2. content in the glaciated region around Muztagata.

关键词： atmospheric CO2 and H2. concentration, continuous monitoring, glaciation region, Muztagata.

Origin of summer monsoon rainfall identified by δ1.O inprecipitation

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Science Bulletin 2005年第23期50卷 2761-2764页

作者： PANG Hongxi1. HE Yuanqing1. 2. ZHANG Zhonglin1. LU Aigang1. GU Juan1.& ZHAO Jingdong1.1. Key Laboratory of Cryosphere and Environment, {1. and arid Re-gions {2. and engineering research Institute, chinese academy of sciences, lanzhou 730000, china 2. Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 1.0085, china Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

A negative correlation between δ 1.O in mon-soon precipitation and f, the ratio of precipitable water in monsoon region to that in water source area, is hypothesized. Using the Rayleigh model, a new method for identifying ori-gin of summer monsoon rainfall is developed based on the hypothesis. In order to validate the method, the isotopic data at New Delhi, a typical station in the southwest monsoon region, and Hong Kong, a typical station in the southeast monsoon region, were collected and analyzed for case studies. The case studies indicate that the water source areas of the monsoon rainfall at the two stations identified by the method are accordant with the general atmosphere circulation pat-terns. The method developed in this paper is significantly important for tracing the origin of summer monsoon pre-cipitation.

关键词： monsoon stable isotopes origin of monsoon precipita-tion.

Relationships between δ ^(1.)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth {1. 2006年第1期49卷 27-35页

作者： YU Wusheng1,2. YAO Tandong1,2. TIAN Lide1,2. LI Zhen2. SUN Weizhen2.& WANG Yu2.1. Laboratory of Environment and Process on Tibetan Plateau, Institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085,{2. 2. Key Laboratory of Cryosphere and Environment, Jointly Established by cold and arid regions environmental and Engi-neering research Institute and Institute of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological {12.,{2. Meteorological Administration, CAS, lanzhou 730000,{2. 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during {1.0{1.{1.03, this paper presents the relationship between δ 1.O in precipitation and air temperature, and discusses the effect of moisture transport on δ 1.O in precipitation. Results show that air temperature correlates positively with δ 1.O in precipitation, and the temperature effect controls the δ 1.O of precipitation in this area. The Muztagata region exhibits high δ 1.O values in summer precipi-tation, similar to those shown at stations in adjacent regions. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 1.O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 1.O in precipitation at Muztagata.

关键词： Muztagata, δ1.O, precipitation, temperature, moisture transport.