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  • Original Articles
    PAN Peipei, YANG Guishan, SU Weizhong
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    Land use/cover change (LUCC) is one of the hot issues of global changes. The impact of land usechange on land productivity is an important part of effects of LUCC. Based on the concepts of land use changeand land productivity, this paper summarizes the main research contents and methods mainly from the aspect oftheir impacts on the potential land productivity, food production capacity and soil quality. It also discusses thescales of impact in this study. Then, it further points out main problems in current studies. Finally, the paper suggeststhat future research should focus on the impact of land use changes in the structure, pattern and intensityon cultivated land productivity, especially in the range of small scale, and emphasize the application of spatial analysis, dynamic evaluation model and synthesis of scales. This article also puts forward that this research hasbecome an inevitable strategic choice and it is of great significance to establish sustainable land use patterns andto ensure national food security.
  • Original Articles
    HUANG Yunfeng, CUI Shenghui, SHI Longyu
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    Peri-urban area emerged with the rapid urbanization and is a new transitional region between urbanand rural areas. The most important characteristics of the peri-urabn areas are the large rates of changes and conflictsbetween landuses. Through the change of ecosystem's internal structure and function, land use/coverchange (LUCC) has affected the values of ecosystem services and has been a major driving factor. Taking JimeiDistrict (a peri-urban area) in Xiamen City as an example, the authors examined the land use pattern from 1987to 2007 by integrating remote sensing data and evaluate the regional ecosystem services based on the revisedmethod of equivalent value per unit area of ecosystem services in China in 2007. The coupling changes betweenland systems and ecosystem services were used to identify the effects and mechanisms of LUCC on ecosystem services. Results showed that along with the promotion of land use intensity, the total ecosystem services valueshad shown a curved trend of change, with supplying and regulating service being main ecosystem service types;land use intensity was negative for supplying, regulating, and supporting cultural services. With the rapid urbanizationin Jimei District, there will be more land to be transformed to construction land. It can be predicted thatthe decreasing trend of ecosystem service value will continue in the future, and we should use the ecological comprehensive treatment to slow down that trend.
  • Original Articles
    SHEN Yuancun, WANG Xiuhong, YUE Yaojie
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    Based on ecological characteristics of land types, and by using Zhengning County, Gansu Province locatedon the Loess Plateau as a study area, the coupled relation between ecological suitability and ecological system of land types was studied. The research indicated that there is a satisfactory coupled relation between landtypes and ecological systems, which provides the main basis for land ecological evaluation and construction ofrational ecological system structure. With restructuring rational ecological system and increasing comprehensive ecological functions in Zhengning County as their objectives, the authors proposed ecological construction strategies and measures for the county, which is also helpful to the ecological construction on the Loess Plateau.
  • Original Articles
    HUANG Chong, LIU Gaohuan, FU Xin, LI Yafei, LIU Qingsheng, WANG Xingong
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    As satellite remote sensing provides a large spatial view, combined with a relatively high return frequency,it is a very cost-effective tool for wetland restoration monitoring. In this paper HJ-1 micro satellite remotesensing data were used for monitoring and evaluating the effect of wetland restoration through water transfer project in the Yellow River Delta. The results showed that the flow conditions of the former abandoned channel have been greatly improved through water transfer from the Yellow River. The river water body area increasedby 526 ha, and the hydrological situation of the river floodplain has much ameliorated. Some 437 ha of degraded wetlands in the nature reserve have been restored, which will be beneficial to biodiversity maintainance and habitat improvement in the Yellow River Delta. The paper argued that the Chinese HJ-1 remote sensingdata, with rich ground spectrum information and a high temporal resolution, can be used as an important source for wetland surveying and monitoring. However, it is necessary to further explore the spectral information of HJ-1 to deeply understand the long-term effect of water transfer and wetland restoration on regional ecosystemsat large spatial-temporal scales.
  • Original Articles
    LI Zheng, WANG Jun, BAI Zhongke, GUO Yiqiang, YU Li
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    Based on the land use change data in Guizhou province from 1996 to 2008, and by the evaluation ofecosystem service values, coefficient of sensitivity and grey forecast model, this paper estimated the changes inland use and ecosystem service values, and predicted the land use structure and ecosystem services values. Theresults are shown as follows. (1) During 1996 and 2008 in Guizhou province, the land use structures showed thatforest land, garden land, construction land and water body increased significantly, while cultivated land, grasslandand unused land showed a decreasing trend. (2) The total ecosystem services values in the study area in2008 is 5.908 billions yuan more than those in 1996, an increase of 3.01%. (3) The change rate of ecosystem servicesvalue of the northwestern part is much larger than that in the southeastern part of the study area. 4) The coefficient sensitivity analysis showed that the ecological value coefficients are reasonable, and the ecosystem servicevalues lack flexibility in the study area. (5) The land use structures of Guizhou province in 2015 and 2020 were predicted by using the GM (1, 1) model. The trend of woodland and construction land would maintain acontinual increase while the cultivated land a continual decrease in the ten years to come. The total ecosystem services value in 2020 would reach 21.19×108 yuan. The information entropy values of land use structure were1.4320 and 1.4331, respectively, implying that land use structures tend to be more and more balanced.
  • Original Articles
    FAN Lan, LU Changhe, CHEN Zhao
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    Crop growth model is a useful tool for quantitative evaluation of crop production potentials. Since itsstudy was first published in 1985, EPIC model has been widely used in the world because of its powerful functionality.In this paper, the main structure, function and data requirements were firstly summarized, and then the model applications in the world and China were reviewed. In China, since the first application in 2001, the EPIC model was used to evaluate crop yield potentials, quantify effects of irrigation and climate change on crop production,estimate nutrient losses and soil carbon storage, and predict soil losses. Finally, a brief discussion and suggestions were given on the model use.
  • Original Articles
    HAO Lisheng, DING Yihui
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    The precipitation reduction in North China has made the already intense water resource situation evenmore severe, which poses a great threat to local industrial and agricultural production and future development,and has aroused great concern of the governments at all levels and the scientific community. For example, to alleviatethe situation of water stress in North China, the Central Government has implemented the South-to-NorthWater Diversion Project. What is the the mechanism for changes in North China precipitation? Understandingthe problem can help us to recognize the future trends and reverse time in precipitation of North China. Fromthe angle of interdecadal variations of precipitation in North China, this article mainly reviewed the impact mechanism on summer precipitation in North China on the sea surface temperature, the East Asian summer monsoon,subtropical high, snow and sea ice changes. Finally, thisp paper pointed out the direction for future research,including: what is the time for North China precipitation transformation from less to more; the mechanism of ENSO impact on precipitation in North China and the influence of ENSO long-term variation trend onprecipitation in North China; what is the impact mechanism of Indian Ocean sea surface temperature anomalieson summer precipitation in North China; how to better quantitatively describe the East Asian summer monsoon intraseasonal, interannual, decadal variations and their impact mechanism on summer rainfall in North China;subtropical high intraseasonal changes, long-term changes and how they affect summer precipitation in North China.
  • Original Articles
    LI Zhaoguo, Lü Shihua, AO Yinhuan, WANG Shaoying
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    In this paper, by using the measured data observed in Lake Ngoring lakeside region during the summerof 2010, five fine days with continuous and integrated data are selected, and then their characteristics of dailyvariations of the surface radiation and energy budget and CO2 flux and microclimate are analyzed over thehigh-cold meadow vegetation ecosystem in summer. The main conclusions can be drawn as follows. (1) For fine summer weather, the characteristics of micrometeorology are significantly affected by the lake breeze in lakeside region, not only the wind direction changes alternately but also the difference in temperature is relatively small between day and night. In addition, the updraft prevails in lakeside region, and the vertical wind speed andthe friction velocity are much greater than those in Maqu grasslands. (2) The daily mean values of solar radiationand net radiation are larger than those in Maqu grasslands and Jinta oasis. As to the energy budget, the latentflux is significantly higher than the sensible flux, and the energy imbalance is large in the observation. There aredistinct temperature inversion and humidity inversion phenomena in the surface layer at the night. (3) The maximum value of carbon absorption usually is observed at about 11o’clock every morning over the meadow in lakeside region, and carbon absorption is significantly more than carbon emission. In terms of the water use efficiency(WUE), it is small, which is similar to that in Haibei meadow.
  • Original Articles
    SHI Guangpu, SHI Yuanyuan, GUO Yuzhen, CHEN Shaoyong, LIN Shu, GUO Junting
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    Based on meteorological data of autumn cloud shape and surface air temperature at 29 meteorologicalstations in the Qilian Mountains and the surrounding areas during 1961-2001, the temporal variation and spatial distribution of autumn stratiform cloud arising frequency and the relationship between it and climate warming were analyzed, and the NCEP/NCAR global reanalysis data in the corresponding period were selected to analyzethe circulation of autumn stratiform cloud in this region. The results are shown as follows. (1) The autumn stratiformcloud arising frequency in the Qilian Mts. region is 8%~26%, presenting a spatial distribution of less inthe (north)west and abundant in the (south)east. (2) The autumn mean air temperature increased by 1.2℃ with arate of 0.29℃/10a in recent 41 years, and the abrupt change occurred in the mid-1980s. (3) The autumn stratiformcloud arising frequency decreased by 11% at a rate of -2.7%/10a, which was corresponding to the synchronoussignificant warming since the mid-1980s. The autumn stratiform cloud arising frequency decreased moresignificantly, and the autumn stratiform cloud arising frequency and air temperature presented an anti-phasetrend. (4) In the background of climate warming, the autumn stratiform cloud arising frequency in the Qilian Mts. region decreased, with a decreasing amplitude increasing from northwest to southeast. When the autumn average temperature increased by 1℃, the autumn stratiform cloud arising frequency decreased by 2%~10% overmost parts of the Qilian Mts. region, 2%~4% in the western and central parts, and 4%~10% in the eastern part.(5) There was a significant difference in 500hPa atmospheric circulation between abundant and less years of autumn stratiform cloud in the Qilian Mts. region. In abundant years, polar vortex extends to northern Asia, theeastern Asia deep trough is weaker, and the Ural high pressure ridge is stronger. Due to the north-northwest airflowbefore the ridge, the polar cold air flows to Northwest China in a northwest path, uninterrupted low-valuesystems develop and move towards east from Central Asia to the Qinghai-Tibet Plateau. In the meantime, southerntrough strengthened and the transportation of the warm and wet air flow from the Arabian Sea, the South China Sea and the East China Sea to the inland areas were markedly strengthened. It met with the cold air which enteredthe northern plateau region, leading to an increase in the autumn stratiform cloud arising frequency in theQilian Mts. region. In less years, the warm anticyclone range from Central Asia to Northwest China is abnormally strengthened, the East Asia deep trough is stronger, and cold air moves by east, presenting a significant winter monsoon characteristic from Asia to Western Pacific. North wind strengthened and made against the transportation of warm and wet flows from Southeast to Northwest China, thus there was less possibility for their meetingin the Qilian Mts. region, thus the autumn stratiform cloud arising frequency decreased. (6) The northward watervapor transportation from the Indian Ocean to the Bay of Bengal, the northward shift of east airflow over the subtropic Western Pacific near the South China Sea and Indo-China Peninsula, and the westerlies latitudinal watervapor transportation over the Mediterranean Sea and the Caspian Sea are the three channels for water vaportransportation which affect the autumn stratiform cloud arising frequency and then affect the autumn precipitationin the Qilian Mts. region.
  • Original Articles
    LI Mingsheng, ZHANG Jianhui, LIANG Nian, LIN Lanyu, LI Qian, WEN Xiangcai
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    In order to compare the applicability and limitation of some common methods for water environmental quality assessment, we analyzed seven common methods, such as single-factor assessment, average pollution index, Nemerow index, grey correlation analysis, fuzzy comprehensive assessment, matter element extension assessment,comprehensive water quality identification index, based on the water quality monitoring data of 190surface water sections under national monitoring program in the Yangtze River drainage basin and Huaihe drainage basin. The main results could be summarized as follows. (1) Index weight had little effect on the assessment result. Among the 190 surface water sections under national monitoring program, 73.7% did not change distinctly.Matter element extension assessment method was sensitive to index weight. (2) When the assessment factors’pollution extent was similar, the average pollution index had the advantage. While the specific factor’s pollutionextent was outstanding, the Nemerow index was more suitable. The result of average pollution index conformed to the result of Nemerow index, and the correlation coefficient was 0.94. The correlation coefficient was increasing when the water pollution was more serious. (3) The results of grading score method and single-factor assessment had significant difference. There were only about 10% of the 190 sections whose results were consistent.And the difference was bigger while the water quality is getting worse. (4) The results of the seven methodswere correlative to a certain extent. The correlation coefficient of assessment rank was 0.7 or so. Based on anoverall consideration of the advantages and disadvantages of these methods, and according to the requirement of environmental management, the single-factor assessment method and water quality identification index are the optimal methods. Therefore, these two methods could be used in combination when assessing water quality.
  • Original Articles
    ZOU Yue, ZHANG Bo
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    It is a hot issue of ecological water demand in the study of water problem in recent years, especiallyin arid areas where the ecological environment deteriorated rapidly. Climate changes and human activities canlead to hydrological change, which means the local hydrological condition has changed and broke the ecologicalbalance. The authors adopted monthly runoff series data of 60 years at hydrological monitoring station of Yingluoxia in the Heihe River basin during the period 1947-2006. The difference plot curve-combined method ofrank test was used to identify the change point of hydrological processes and causes of these changes. On this basis,L-moment is used to evaluate the parameters of generalized extreme value (GEV) distribution of the monthlyflow series before hydrological change, and to calculate the maximum probability density runoff, which is theecological water demand of that month. The result shows that the ecological calculating method which takes the hydrological change into consideration is practicable in the Heihe River. Before and after the hydrological variability,the frequency to meet the ecological water demand will change significantly at Yingluoxia station. The climatic reasons inevitably exert influence on the volume of the runoff. So it is important to get a better understanding of ecological water demand in river ecosystem management and socio-economic sustainable development in arid areas.
  • Original Articles
    GU Lei, SONG Bo, TONG Zhiqi, MA Jianhua
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    On Lianyungang-Horgas highway, two typical sampling transects along the Zhengzhou-Shangqiu section,Wanliu transect operated in 1994 and Xiaowangzhuang transect operated in 2001, were chosen to investigate the distribution and potential ecological risks of heavy metals (Cd, Cu, Pb, Zn, Ni, and Cr) in roadside soils.Soil samples were collected at different distances from the highway. The contents and spatial distribution ofheavy metals in the soils were analyzed. The ecological risks of soil heavy metals were evaluated based on potential ecological risk index (RI) put fowward by Håkanson. The results show that heavy metal concentrations and potential ecological risks on Wanliu transect (at moderate ecological risk level) were higher than those on Xiaowangzhuang transect (at slight ecological risk level) because of longer operated time. Most of the heavy metal concentrations and potential ecological risks present a skew distribution with the distance from highway roadbed. The highest risk indexes for different metals on Wanliu transect are observed at 50~100 m from highway roadbed, while those on Xiaowangzhuang transect at 35 m from the roadbed. The total risk index was mainly contributed by cadmium with the averagely proportion of 61.39% (ECd/RI). Therefore cadmium is the mainfactor influencing potential ecological risks. Potential ecological risk index is a rigorous method, because it includesnot only concentrations of heavy metals, but also ecological effects and toxicological characters. To applythe method of RI in estimating the potential ecological risk of pollutants, the RI standards for different levels of potential ecological risk should be modified according to the pollutant amounts studied and their toxic-response factors.
  • Original Articles
    WAN Zhiwei, YANG Xiaoyan, GE Quansheng, FAN Changsheng, ZHOU Guangming, MA Zhikun
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    Sheshantou is an important Neolithic archaeological site in Jiangxi province, but hardly any environmental archaeology and paleoethnobotany research had been done about it. Starch grain analysis, as a new micro-remain method, has been chosen in this research. And some potteries-two pottery bowls and a pottery jar,excavated from the She shantou site were examined in this study. The results show that the food residues attachedto the inner wall of the pottery include lots of starch grains from different plants such as Oryza spp., Setariaspp., an amount of root and tuber, and a few starch grains cannot be identified at this time which maybe caused by the appearance of a number of transient starch grains produced within the process of photosynthesis.Starch grains from Oryza spp. 7 grains represent 21% of the total, Starch grains from Setaria spp. 9 grains represent 26%, and only 2 grains from roots and tubers. The results probably indicate that, 4500~3500 a BP, the ancient people lived in the region of Sheshantou had made use of rice and millet, and also taken some root and tuberas their food resource. This research supplied some evidences for the study on paleoethnobotany and environmental archaeology in Southern China, and shed some new light on the research of ancient people diet. Andthese results also demonstrate that ancient starch grains can be reserved in archaeological sites of Southern China,which will be a useful complement to other research methods in the near future.
  • Original Articles
    ZHAO Xinfeng, XU Hailiang, LIU Xinhua, ZHANG Peng, LIU Zhiyou, HONG Hui
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    Distribution of the roots of drip irrigated Elaeagnus angustifolia with different irrigation amountswere investigated and the influence of root on soil water content was analyzed in extremely arid areas on Kalamijioasis in the lower reaches of the Tarim River. Three treatments were: 18 L, 30 L and 48 L each time onetree. This paper conducted a study on root biomass density and roots quantity. The results are shown as follows.(1) After long-term use of drip irrigation, most of Elaeagnus angustifolia root is distributed in the shallow soillayer (0~40 cm), and root branching ability reduces with the increase of soil depth. The root biomass of Elaeag?nus angustifolia in the 0-60 cm soil is up to 86% in the cumulative percentage. (2) The higher amount of irrigation resulted in enhancement in the total root biomass, but did not lead to the development of the root system inthe deep layer. Therefore, by using the irrigation quota of 48 L formed a deeper layer of soil moisture, the abilityof striking-root did not show an increasing trend with the larger irrigation amount, namely, the capacity of deepeningand depth of the roots did not increase with the increased irrigation amounts. In treatment 48 L, the ratioof soil root content in the layers of 20~40 cm/0~20 cm is small (only 0.6), and biomass is mainly concentrated in the surface; in treatment 30 L, the ratio of soil root content in the layers of 20-40 cm/0-20 cm is larger (0.75).(3) Roots of ≥5 mm increases with the increase in the amount of drip irrigation. In treatment 30 L, roots of 5mm≥φ ≥2 mm occupy the largest part of all. In treatment 18 L, there are the smallest numbers of thick roots(φ≥5 mm) and fine roots (φ≤2 mm). It is proposed that, to achieve the sustainable development of shelterbelt system in the extreme arid areas, large-scale irrigation of shelterbelt system should be taken in a variety of irrigation measures: to take the appropriate deficit irrigation in the season of competition for water between cottonand shelterbelt (from May to July), and the irrigation quota can be increased or the irrigation can be done 1-2times after August.
  • Original Articles
    GENG Yuanbo, SHI Jingjing
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    Litter decomposition is a main linkage of material cycle in grassland ecosystem. In the meantime, nutrient elements release and accumulation play an important role in the process of degraded grassland recovery. Inthis paper, we briefly reviewed the research progress of litter decomposition and the biogeochemical behaviour of nutrient elements in grassland at home and broad from two aspects: the main factors which affect litter decomposition rate, including the properties of litter, external environment (biological and non-biological factors) andmixture effects; the release and accumulation of plant nutrient elements when litter decomposes. Grassland litterde composition rates, in common circumstances, are positively correlated with initial litter N, P and K, while negatively correlated with C/N, C/P, lignin and cellulose, and insignificantly correlated with the nutrients ambient.The effects of non-additive effects are dependent on N and P contents as well as litter diversities. In the process of litter decomposition, an overall trend shows that litter accumulates N while it releases K and P at the primarystage of decomposition whereas it shows no obvious regularity on the immobilization of Na, Ca and Mg for differentparts or types of species. Different contents of each nutrient, different stages of decomposition, differenttypes of species, non-additive and soil environment are the main factors that affect the nutrients release and accumulation.It can be concluded that the exploration of the interaction of factors, the mechanism in mixture decomposition,the release and accumulation of some major and trace nutrient elements will be research hotspots in thefuture.