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Variations of Snow Temperature and their Influence on Snow Cover Physical Parameters in the Western Tianshan Mountains,china

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Journal of Mountain Science 2011年第6期8卷 827-837页

作者： CHEN Xia WEI WenShou LIU MingZhe GU GuangQin xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China Hebei Key Laboratory for Meteorology and Eco-environmen Shijiazhuang 050021 China HeBei Climate Center Shijiazhuang 050021 China institute of Desert Meteorology China Meteorological Administration Urumqi 830011 China Tianshan Station for Snow-cover and Avalanche Research Chinese Academy of Sciences Urumqi 830011 China

This article discussed about snow temperature variations and their impact on snow cover parameters. Automatic temperature recorders were used to sample at lo-minute intervals at the Tianshan Station for Snow-cover and Avalanche Research, chinese snow temperature academy of sciences. lo-layer and the snow cover parameters were measured by the snow property analyzer （Snow Fork） in its Stable period, Interim period and Snow melting period. Results indicate that the amplitude of the diurnal fluctuation in the temperature during Snow melting period is 1.62 times greater than that during Stable period. Time up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours, and lags behind the peak atmospheric temperature by more than 0.2 hours during all three periods. The optimal fitted function of snow temperature profile becomes more complicated from Stable period to Snow melting period. 22 h temperature profiles in Stable period are the optimal fitted by cubic polynomial equation. In Interim period and Snow melting period, temperature profiles are optimal fitted by exponential equation between sunset and sunrise, and by Fourier function when solar radiation is strong. The vertical gradient in the snow temperature reaches its maximum value at the snow surface for three periods. The peak of this maximum value occurs during Stableperiod, and is 4.46 times greater than during Interim period. The absolute value of temperature gradient is lower than 0.1℃ cm-1 for 30 cm beneath snow surface. Snow temperature and temperature gradient in Stable period-Interim period indirectly cause increase （decrease） of snow density mainly by increasing （decreasing） permittivity. While it dramatically increases its water content to change its permittivity and snow density in Snow melting period.

关键词： Snow temperature Vertical temperaturegradient Optimal fitting function Snow density Western Tianshan Mountains china

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Tissue Distribution and Purification of Prophenoloxidase in Larvae of Asian Corn Borer, Ostrinia furnacalis Guenée (Lepidoptera: Pyralidae)

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 360-364页

作者： Cong-Jing FENG1,2 and Wen-Jun FU1* 1institute of Plant Physiology and ecology, Shanghai institute for Biological sciences, the chinese academy of sciences, Shanghai 200025, china 2The GraduateSchool of the chinese academy of sciences, Beijing 100039, china institute of Plant Physiology and ecology Shanghai Institute for Biological Sciences the Chinese Academy of Sciences The Graduate School of the chinese academy of sciences

Using ammonium sulphate precipitation, Blue-Sepharose CL-6B, Phenyl-Sepharose CL-4B, prophenoloxidase (PPO) was isolated and purified from hemolymph of Ostrinia furnacalis larvae. This zy- mogen was a heterodimer, and composed of two subunits with the relative molecular mass ranging from 66.2 kD to 97.4 kD determined by SDS-PAGE. Western blotting and indirect immunofluorescence test showed that PPO was present in integument, hemolymph plasma and cell membrane of granular hemocytes and oenocytoids of O. furnacalis larvae.

关键词： Ostrinia furnacalis prophenoloxidase tissue distribution purification

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The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, china institute of Applied ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of sciences, Beijing 100101, china 1. State Key Lab of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

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LAND RECLAMATION PROCESS IN NORTHEAST china SINCE 1900

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chinese Geographical Science 2003年第2期13卷 119-123页

作者： ZHANG Bai, CUI Hai-shan, YU Lei, HE Yan-fen (Northeast institute of geography and Agricultural ecology, chinese academy of sciences, Changchun 130012,P.R.china) Northeast institute of geography and Agricultural ecology Chinese Academy of Sciences Changchun P. R. China

Northeast china is an important agricultural region in china. The NortheastPlain is the largest plain in the country and one of the three famous black soil zones in the *** of fertility of the soil, however, large-scale agricultural development mainly took placesince 1900. The land exploitation and utilization has been fast and intensive in this region sincethen and change in the land-cover process has been remarkable. Both national and internationalresearchers on land use and land cover are paying more attention to these processes in this regionand their implication for local ecological environment. This article discusses the land reclamationprocesses and their main driving forces in Northeast china since 1900. According to the research,the 20th century was the most important period for land reclamation in Northeast china. In theseyears the rate, intensity and quantity of land reclamation have been staggering, and more than 100000km^2 of land was converted into farmland. This magnitude of land reclamation inland is unique inthe world. Research on the land reclamation of Northeast china can provide some data on the effectof human activity on environment. As in many other places in the world, the primary driving force ofreclamation in Northeast china was the increasing pressure of population. In the 20th century thepopulation increased from 10 x 10~6 to 110 x 10~6 in Northeast china and from 400 x 10~6 to 1. 3 x10^9 in china. Population pressure is thus the most important driving force for land reclamation.

关键词： land reclamation process northeast china 20th century

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Value of ecosystem services in china

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chinese Science Bulletin 2000年第10期45卷 870-876页

作者： CHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation ecology, institute of Botany, chinese academy of sciences, Beijing 100093, china Current address: institute of Natural Resources and Regional Planning, chinese academy of Agricultural sciences, Beijing 100081, china Laboratory of Quantitative Vegetation ecology Institute of Botany Chinese Academy of Sciences Beijing China

The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in china were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of china (1:4 000 000), and then the distribution map of ecosystem services of china was drawn. According to our calculation, the total value of ecosystem services in china is 77 834.48×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.46×108 yuan per annum, and that for marine ecosystem is 21 736.02×108 yuan per annum. The value of ecosystem services in china is 1.73 times bigger

关键词： ecosystem function service.

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ENVIRONMENTAL CHANGES IN NORTHWEST ARID china DURINGRECENT 40 YEARS

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Journal of Geographical sciences 1994年第Z1期4卷 25-33页

作者： WANG sHUji(xinjiang institute of geography, CAS,urumqi 83.011People’s Republic of china)

The oases environment of arid lands in Northwest chinahas been improved during recent 40 years, but the generalenvironments out of the oases have been deteriorating. This aniclediscusses the cause and effect of the environmental changes withthe aid of rich data and puts forward countermeasures fOr eco-enviromnental protection and improvement.

关键词： desertifiction environmental protection arid lands china

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The fluxes and controlling factors of N_2O and CH_4 emissions from freshwater marsh in Northeast china

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Science china Earth sciences 2010年第5期53卷 700-709页

作者： YU JunBao1,2, LIU JingShuang2, SUN ZhiGao1, SUN WeiDong3, WANG JinDa2, WANG GuoPing2 & CHEN XiaoBing1 1 Key Lab of Coastal Envionment Processed, Yantai institute of Coastal Zone Research for Sustainable Development, chinese academy of sciences, Yantai 264003, china 2 Key Lab of Wetland ecology and Environment, Northeast institute of geography and Agricultural ecology, chinese academy of sciences, Changchun 130012, china 3 Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china 1. Key Lab of Coastal Envionment Processed Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China2. Key Lab of Wetland Ecology and Environment Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 China3. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast china, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.

关键词： freeze-thaw region freshwater marsh methane nitrous oxide controlling factors

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Emission of landfill gas in Qingdao, china

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Journal of Environmental sciences 1996年第3期8卷 292-297页

作者： Gao Jixi Shen Yingwa Cao Hongfa Shu Jianmin(institute of ecology, chinese Research academy of Environmental sciences,Beijing 100012, china) institute of ecology Chinese Res. Acad. of Environ. Sci. Beijing 100012 China

A study on landfill gas emission in Qingdao,china was carried out. The results showed that the generation of landfill gas with maximum methane concentration occurred several months after the refuse was disposed and the steady emission of landfill gas could remain two *** variation of landfill gas production was associated with temperature. In June, the emission of landfill gas rose gradually from morning to evening, but in September, it rose in the morning, and then fell in the afternoon. From June to August, the emission of landfill gas showed rising trend,but it declined quite quickly from September to December. In different seasons,the outflow rate of landfill gas varied from depth to depth in the refuse site. When earth temperature was higher in summer, the emission of landfill gas did not correspond with the depth of refuse sites, but when temperature fell in winter, and the temperature became a limited factor to the gas production,the outflow of landfill gas increased with increasing in depth of refuse piling.

关键词： landfill gas emission china

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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui institute of Applied ecology, chinese academy of sciences, Shenyang 110016, china School of Forestry, Northeast Forestry University, Harbin 150040, china State Key Lab of Systems ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, china Graduate University of chinese academy of sciences, Beijing 100039, china 1. institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China 2. School of Forestry Northeast Forestry University Harbin 150040 China 3. State Key Lab of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 4. Graduate University of chinese academy of sciences Beijing 100039 China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was44.2%, much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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Landscape planning and ecology construction of wetland comprehensive protected area system in the Sanjiang Plain

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Journal of Environmental sciences 2000年第3期12卷 361-366页

作者： LIU Hong\|yu, LU Xian\|guo, LIU Zhen\|qian (Changchun institute of geography, chinese academy of sciences, Changchun 130021, china) 中科院长春地理所吉林长春 1 3 0 0 2

Wetland is one of the richest biodiversity areas in the earth. The main purpose of establishing wetland protected area is to protect biodiversity, and the protection of ecosystem diversity and landscape diversity is the key to protect biodiversity. In order to protect regional ecosystem and landscape, it is a good way to establish wetland comprehensive protected area which connected wetland nature reserves by habitat corridors. The Sanjiang Plain as a study area, its landscape evaluation index system on wetland protected area was studied, and some problems on landscape planning and ecology construction were further approached in this *** showed that establishing wetland comprehensive protected area is very important to protect regional wetlands, to maintain ecological balance, and to improve the sustainable development of agriculture and industry in this region.

关键词： landscape planning ecology construction wetland protected area

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