Table of Content

15 September 2013, Volume 30 Issue 5 Previous Issue    Next Issue

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Relationship between Sea Temperature in EarlyNino 3.4 Region  and Air Temperature and Precipitation in Ningxia in January and February YANG Qin, DING Yong-Hong, LIN Shu 2013, 30 (5):  769-775.  Abstract ( 1739 )   PDF (775KB) ( 1307 )   The strong and weak correlations of decadal variation of respective indices of circulation characteristic qualities, such as the polar vortex in Northern Hemisphere, Asia polar vortex area and strength index, and East Asian trough strength and location index, were analyzed and tested to pass through significant level. In strong correlation periods, the correlations between these circulation characteristic qualities and air temperature and precipitation anomalies in Ningxia in January and February revealed that the stability of air temperature and precipitation were high, that means that, as the reference factors in prediction, these circulation characteristic qualities were very important. The correlation analysis and significance test between the earlyNino 3.4 region SST monitoring state in December and the air temperature and precipitation in Ningxia in next January and February from 1961 to 2010 revealed that, under the El Nino/La Nina events, there was a significant positive correlation and a negative correlation between air temperature and precipitation since 2000 under climate warming; under an El Nino event, there was a significant positive and negative correlation between air temperature and precipitation in February; under a La Nina event, there was a significant negative correlation between air temperature and precipitation in February; under a constant SST, there was no significant correlation between air temperature and precipitation in January and February, and all these correlations passed the significant level test. Fifteen La Nina events occurred from 1961 to 2010, their probabilities affecting air temperature and precipitation anomalies in Ningxia in January and February were described, and it was verified with X2 test that there was no significant correlation between La Nina event and air temperature and precipitation in January and February. References | Related Articles | Metrics

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Climate Change in Zhenglan Banner, Inner Mongolia in Recent 40 Years LI Peng, YANG Ting-Ting, WU Xin-Hong, 吕Shi-Hai , LIU Tong-Hai 2013, 30 (5):  776-780.  Abstract ( 1811 )   PDF (2448KB) ( 1139 )   There are many types of grasslands in Inner Mongolia, and grasslands are of extremely sensitive to climate change. Climate change is not only an important factor in assessing regional ecology and environment, but also a research focus all over the world in recent years. The study on climate change is of great significance for making policy and working out management measures so as to adapt local climate change. In this paper, the main characteristics of climate change in the study area were analyzed using regression analysis based on the temperature and precipitation data observed in Zhenglan Banner, Inner Mongolia during the period of 1970-2009. The results show that the temperature in the banner in recent decades was in an increase trend, its change trend rate was 0.57 ℃·（10a）-1, and the average annual temperature in recent 40 years was 2.26 ℃, in which the temperature increase was the most significant in the first decade of this century, and the annual temperature was up to 3.07 ℃. Precipitation was also in an increase trend, its change trend rate was 4.85 mm·（10a）-1, the average annual precipitation in recent 40 years was 352.31 mm, in which the annual precipitation was the highest (398.74 mm) in the 1990s. However, the annual precipitation was sharply decreased and down to the lowest value in the first decade of this century since recent 40 years, and it was 19.62 mm lower than the average. Temporally, it was relatively dry and cold in the banner in the 1970s, and began to become warming and wetting in the 1980s, more warming and wetting in the 1990s, and warming and drying in the first decade of this century.   References | Related Articles | Metrics

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Spatiotemporal Change of Duration and Accumulated Temperature  of Temperature ≥ 0 ℃ in Xinjiang in Recent 50 Years PU Zong-Chao, ZHANG Shan-Qing, LI Jing-Lin, WANG Ming-Quan 2013, 30 (5):  781-788.  Abstract ( 1478 )   PDF (2711KB) ( 980 )   Global warming has become as an indisputable fact, under its impact, the agroclimatic resources, especially the heat resources, will be significantly changed in most parts of the world. The duration and accumulated temperature of temperature ≥0 ℃ were the important indices of evaluating heat resources. Xinjiang is an important area of agricultural and animal husbandry production in China, but heat shortage is one of the main factors restricting agricultural and animal husbandry production. Therefore, it is of an important practical significance to research the spatiotemporal changes of the first date, final date, duration and accumulated temperature of temperature ≥0 ℃under the background of global warming. In this paper, the methods of linear regression, accumulative anomaly, Ttest and ArcGISbased mixed interpolation were used to analyze the spatiotemporal changes of the first date, final date, duration and accumulated temperature of temperature ≥0 ℃ based on the daily temperature data observed by 95 meteorological stations in Xinjiang during the period of 1961-2010. The main results are as follows: the spatial distribution of the first date, final date, duration and accumulated temperature of temperature ≥0 ℃ was obviously different from different regions in Xinjiang. Generally, the first date of temperature ≥0 ℃came earlier in south Xinjiang than in north Xinjiang, and it also came earlier in the plains and basins than in the mountainous regions. The final date of temperature ≥0 ℃ was just opposite to the first date. The duration and accumulated temperature of temperature ≥0 ℃ were longer and higher in south Xinjiang than in north Xinjiang, and they were also longer and higher in the plains and basins than in the mountainous regions. Under the background of global warming, the mean first date of temperature ≥0 ℃ at 95 meteorological stations came earlier with a rate of -0.86 d·（10a）-1, and its abrupt change occurred in 1997. The mean final date of temperature ≥0 ℃ came later with a rate of 1.72 d·（10a）-1, and its abrupt change occurred in 1994. The duration and accumulated temperature of temperature ≥0 ℃ were in an increase trend with rates of 2.58 d·（10a）-1and 66.26 ℃·d·（10a）-1 respectively, and their abrupt change occurred in 1997. The change ranges before and after the abrupt change were quite different from different regions, generally, the first date of temperature ≥0 ℃ came earlier in south Xinjiang than in north Xinjiang, the final date of temperature ≥0 ℃ came later in the northern and mountainous areas than in the plains, basins and southern areas, the duration of temperature ≥0 ℃ was prolonged longer in the mountainous areas than in the plains and basins, and the increment of accumulated temperature of temperature ≥0 ℃ was higher in the plains and basins than in the mountainous areas. References | Related Articles | Metrics

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A Rainstorm Weather in Wuwei City on July 29, 2012   YANG Xiao-Ling, DING Wen-Kui, QIAN Pei-Quan, YIN Yu-Chun, YAO Yu-Bi 2013, 30 (5):  789-795.  Abstract ( 1610 )   PDF (2118KB) ( 904 )   The formation causes of convection rainstorm weather in Wuwei City from afternoon to night on July 29, 2012 were systematically analyzed using the conventional weather charts, FY-2D satellite images and meteorological data observed by a meteorological station, and physical quantity field data. The result showed that the rainstorm occurred under the interaction of multiple factors and a certain largescale circulation background. Dramatic change of surface meteorological factors was an energy release process of strong convection weather. Local high humidity and water vapor convergence provided an abundant water vapor source for the rainstorm. Highlevel divergence, lowlevel convergence and strong ascending motion were the dynamic conditions of the rainstorm. Strong unstable energy and unstable stratification were the necessary conditions of enhancing the convection and increasing the rainstorm intensity. Development and strengthening of convective cloud clusters were the direct causes of the rainstorm intensity. References | Related Articles | Metrics

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Change of Rainstorm and Extreme Value of Precipitation  in Different Periods in Shijiazhuang HAN Jun-Cai, WANG Chuan-Hui, CHEN Jing, YAN Fang, YANG Peng, WANG Lei 2013, 30 (5):  796-801.  Abstract ( 1867 )   PDF (1553KB) ( 950 )   Based on the daily precipitation data observed by 17 meteorological stations in Shijiazhuang, the variation of rainstorm days was analyzed, and the distribution of extreme values of precipitation in different periods was studied using the means of Gumbel I extreme value distribution. The results showed that the rainstorm days decreased gradually from the northwest and the southeast to the central area of Shijiazhuang, and most rainstorm days occurred in the northwest. The rainstorm days decreased in most areas in recent decades, but it increased in the north. There were the obvious annual and decadal variations of rainstorm days in Shijiazhuang. The rainstorm days were more during the period from the mid-1970s to the early 1980s and around the mid1990s since the 1970s. There were the 6-year and 16-year fluctuation periods of rainstorm days in the study area. The differences of maximum daily precipitation and maximum precipitation in a continuous precipitation process between the 10-year, 30-year and 50-year periods were high, especially in the northwestern and southwestern mountainous areas. The maximum daily precipitation at all the meteorological stations was higher than 100 mm. References | Related Articles | Metrics

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Response of Shallow Geotemperature to Climatic Change  in the Maqu Area in Upper Reaches of the Yellow River NING He-Ping, ZHANG Jian-Yong, FANG Feng- , AO Ze-Jian 2013, 30 (5):  802-807.  Abstract ( 1406 )   PDF (1479KB) ( 885 )   In this paper, the change trend and abrupt change of shallow geotemperature in the Maqu area in upper reaches of the Yellow River in recent 40 years (1971-2010) were analyzed using the statistical methods, such as the linear trend and abrupt change analysis. The results showed that the mean monthly shallow geotemperature was significantly increased with an increase rate of 0.20-0.71 ℃·（10a）-1, especially in soil layer of 20 cm in depth, and the increase of mean monthly shallow geotemperature at soil depth of 5 cm was the least. Shallow geotmeperature in the Maqu area increased with the increase of depth, and its anomaly was negative before 2000 but positive after 2000. The results suggested that the shallow geotemperature be the lowest in the 1970s, and its peak value occurred in the 2000s. There was an abrupt increase of summer shallow geotemperature at depths of 5, 10, 15 and 20 cm in the 1990s, and also a positive correlation between summer shallow geotemperature and summer air temperature, especially the correlation coefficient between mean summer geotemperature in soil layer of 20 cm in depth and summer air temperature was as high as 0.922. The change trends of both mean summer geotemperature in soil layer of 20 cm and air temperature were strongly consistent. There was a certain positive correlation between summer shallow geotemperature and mean winter precipitation, and the change of summer shallow geotemperature affected the winter precipitation to a certain extent.   References | Related Articles | Metrics

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Validation and Algorithm Redevelopment of MODIS Daily  Fractional Snow Cover Products ZHANG Ying, HUANG Xiao-Dong, Wang-Wei, LIANG Tian-Gang 2013, 30 (5):  808-814.  Abstract ( 2301 )   PDF (2616KB) ( 1498 )   With the development of remote sensing (RS) technology, the RS data have become as the indispensable materials in dynamic monitoring of snow cover, and they play an important role in monitoring snow coverage and analyzing snow disasters. In this paper, the snow coverage retrieved from Landsat TM was taken as the ground truth, the fractional snow coverage (FRA) retrieved from MOD10A1 was validated using Landsat TM image, and an improved segmentation model was proposed for retrieving the FRA by using the MODIS ground reflectivity products (MOD09GA) in some parts of the Qinghai-Tibet Plateau. The results are as follows: ① The average snow coverage retrieved from MOD10A1FRA was 29.16% in our study, but it was 22.45% in TM, and the correlation coefficient of FRA between those two datasets was 0.74; ② The FRA model improved with the MOD09GA product had much better accuracy in SCA acquisition, the average retrieved snow coverage was 21.70%, and the correlation coefficient was 0.85;③ Compared with the “ground truth”, the performance of both the standard error of the improved fractional model and the mean absolute error was better than the MOD10A1/FRA product, which could be used to improve the accuracy of monitoring snow coverage in the study area.   References | Related Articles | Metrics

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Causes Related to Change of Evaporation from 20 cm Pans in the  Urumqi-Changji Region during the Period of 1981-2010 GONG Heng-Rui 2013, 30 (5):  815-821.  Abstract ( 1411 )   PDF (2225KB) ( 795 )   The data of evaporation from 20cm pans in the Urumqi-Changji region during the period of 1981-2010 were used to analyze the evaporation trend in the study area using climate trend method. The results revealed that, in recent 30 years, the evaporation was increased in midmountain and alpine zones, especially in alpine zone; it was in a decrease trend in plain and hill zones, especially in plain. Seasonally, the evaporation was increased in the Daxigou and Tianchi regions, especially in spring and summer; it was in a decrease trend in plain and hill zones, especially in summer, and then in spring, autumn and winter. Accumulative anomaly was used to test the sharp change of evaporation. The results showed that the evaporation in the Urumqi-Changji region was sharply increased in the alpine zone in the late 1990s, the sharp change of evaporation was not significant in midmountain and hill zones, and the evaporation was sharply decreased in most parts of plain in the late 1980s. The analyzed results of the coefficient of partial correlation revealed that the dominant factor affecting evaporation was the increase of temperature in the alpine and midmountain zones, the increase of relative humidity in the hill zone, and the decrease of wind speed in plain.   References | Related Articles | Metrics

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Growth of Organs of Malva rotundifolia Population in  Oasis-desert Ecotone in the Yili Testudo  horsfieldi Nature Reserve JIA Feng-Qin, ZHANG Na, YANG Rui-Rui, ZHANG Fang, DENG Xiao-Yan 2013, 30 (5):  822-826.  Abstract ( 1123 )   PDF (1542KB) ( 948 )   Malva rotundifolia grows in oasis-desert ecotone in the Yili Testudo horsfieldi Nature Reserve. In this paper, the quantitative characters and change of organs of M. rotundifolia in different life cycles were researched. The results show that the number and biomass of organs at late fructification stage of M. rotundifolia population were higher than those at vegetative stage. Leaf number at late fructification stage was 1.25 times of that at vegetative stage, root and stem biomasses were over three times, and the ratio of leaf biomass was 2.06. With the increase of leaf number, there was a linear positive correlation among the biomasses of different organs at vegetative stage, but a power function positive correlation after fructification. There was a power function positive correlation between fruit biomass and root and stem biomass after fructification, but a linear positive relationship between fruit number and root and stem biomass. In different life cycles, there were two different phenotypic plasticity patterns of organs of M. rotundifolia population, i.e. the isogony phenotypic plasticity and allometry phenotypic plasticity. References | Related Articles | Metrics

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Tamarix taklamakanensis Populations and Their Environmental  Factors in the Kumtag Desert YANG Yao-Jun, YUAN Hong-Bo, LIU Shu-Juan, ZHANG Jin-Chun, TANG Jin-Nian, DING Feng 2013, 30 (5):  827-831.  Abstract ( 1334 )   PDF (1333KB) ( 818 )   Seven factors in three elements including geography, soil and water, affecting strongly the Tamarix taklamakanensis populations, were chosen as the indicators to analyze the environmental factors affecting the growth and distribution of T. taklamakanensis populations using the factor analysis. The results showed that soil nutrient was the most important factor related to the survival and development of the populations. Regional severe environment and poor soil restricted obviously the growth and development of the populations. The effect of altitude on the growth and development of the populations was low, and altitude affected the growth and development of the populations together with other factors. The geographical factors affected indirectly the growth and development of the populations. The effect of soil moisture content on the populations reflected the characteristics of groundwater level and its salinity in the habitats. It is difficult to improve the soil which was formed in the longterm geologic evolution and climate change in the Kumtag Desert in a short term, and the shortage of soil nutrient will be continuously maintained in the future. Therefore, it is difficult to conserve and regenerate the plant populations. It is suggested to strengthen the conservation of T. taklamakanensis populations and their habitats and control regional desertification. References | Related Articles | Metrics

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Spatial Distribution and Interspecific Association of Plants in Ecotone between  Mobile Sand Dunes and Interdune Lowlands in the Horqin Sandy Land MIAO Chun-Ping, LI Xue-Hua, JIANG De-Ming 2013, 30 (5):  832-837.  Abstract ( 1261 )   PDF (998KB) ( 914 )   Spatial distribution and interspecific association of plant species are important for revealing how species interact with each other and response to environment change, and hence have important implications for optimal community management and regeneration of degenerated ecosystems. Community structure and interspecies association in the ecotone between mobile sand dunes and interdune lowland in the Horqin Sandy Land were studied using the Pearson correlation, Spearman rank correlation and multivariate analysis (Correspondence Analysis, CA). The results indicated that the difference of species distribution was jointly affected by both environment and biotic factors. There was a selective interspecies accumulation. However, the niches of Agriophyllum squarrosum and Artemisia wudanica were separated from those of other species because they were distributed independently. Salix gordejevii and S. microstachya occupied a similar niche since both of them were distributed on the left side of interdune lowland, but the niche of Hedysarum fruticosum was separated from the niches of other two because it mainly distributed on the other side of interdune lowland. The results of Pearson correlation test were basically consistent with those of Spearman rank correlation test. The community was in unstable succession because the negative correlation coefficients were higher than the positive ones, and there was a niche differentiation. References | Related Articles | Metrics

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Interspecific Relationships among Common Plant Species  in Wetlands in the Yinchuan Plain ZHAO Yong-Quan, HE Tong-Hui, CHENG Zhi, ZHANG Juan-Hong, YANG Ming-Xiu, ZHANG Yu-Feng 2013, 30 (5):  838-844.  Abstract ( 1326 )   PDF (1343KB) ( 923 )   Interspecific relationships among plant species in wetlands in the Yinchuan Plain were studied using the χ2-test, Jaccard associated index, Pearson correlation coefficient and Spearman rank correlation coefficient. The results are as follows: ① The interspecific relationships among the plant species could be expressed by 3 methods, and they were similar but not identical. The χ2-test revealed that there were 24 positive pair-species associations and 4 negative ones, in which 12 were significantly-positive associations and 1 was significantlynegative one. The Pearson correlation coefficient test revealed that there were 30 positive pairspecies correlations without negative one, in which 12 were significantlypositive associations. Spearman rank correlation coefficient test revealed that there were 50 positive pair-species correlations and 8 negative ones, in which 31 were significantlypositive associations and 1 was significantly-negative one; ② The 33 common plant species in wetlands in the Yinchuan Plain could be divided into 4 ecological species groups, i.e. the hydrophyte, hygrophyte, mesophyte and   xerophyte species groups. There were mostly the significantly positive associations among plant groups but negative or significantly negative ones among species groups; ③ In the Yinchuan Plain, the wetland plant communities were usually in an independent pattern, so that the communities were not stable yet and still in a constant succession. Related Articles | Metrics

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Factors Affecting the Diversity of Plant Communities on Ditch Slope in the Ningxia Plain ZHANG Juan-Hong, HE Tong-Hui, CHENG Zhi, ZHANG Yu-Feng 2013, 30 (5):  845-849.  Abstract ( 1331 )   PDF (681KB) ( 957 )   Ditch slope is one of the corridors for species spread and plays an important role in species spread and succession process. The dominant plant communities and the environmental factors affecting them on ditch slope in the Ningxia Plain were studied using the principal component analysis and PCA sequence analysis, and the relationship between plant community and environment was quantitatively analyzed. The results show that the main factors affecting the plant communities on ditch slope in the Ningxia Plain were the soil moisture content and soil organic matter content, and the soil salinity was related to the plant community dominance and biodiversity in a function of Y2=0.516-0.005X1+0.506X2, on which the relationships between the soil salinity and the diversity of plant communities and ecological dominance could be mathematically explained. The results also show that the soil moisture gradient and soil nutrient content were the main factors affecting the distribution of plant communities on ditch slope. As the important irrigation facilities in arid and semiarid regions, ditches could be used to effectively regulate water and fertilizer regime through plant communities. In addition, ditches could also be used to improve the ecological performance by improving hydrologic cycle efficiency in ditch wetlands. References | Related Articles | Metrics

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Regeneration of Stumping of Calligonum caput-medusae in Shelterbelt ZHANG Heng, JIANG Jin, SONG Chun-Wu, LI Xing, JIANG You-Wei 2013, 30 (5):  850-855.  Abstract ( 1290 )   PDF (1491KB) ( 1007 )   The shelterbelts going across the hinterland of the Gurbantonggut Desert have played an important role in protecting the irrigation channels against aeolian sand disasters for many years. In order to keeping the sustainability of the effects of Calligonum caput-medusae shelterbelts, three kinds of stumping experiment of Calligonum were carried out. The percentages of the stumping were 50%, 67% and 78% respectively. The results showed that the stumping of C. caput-medusae could promote the absorbing capability of C. caput-medusae[WTBZ] roots to soil moisture, and the plants could grow rapidly and strongly after stumping. The shelterbelts of C. capu-medusae grew rapidly in the stumping years and played an important role in protecting the irrigation channels against aeolian sand disasters and sand fixation. The effective superficial area of assimilation twigs was increased, and as a result the biomass of assimilation twigs and the productivity of C. caput-medusae were also increased. The regeneration of C. caput-medusae was promoted under these three kinds of stumping, especially under the stumping of 78%. References | Related Articles | Metrics

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Populations of Moderately-halophilic Actinomycetes  in the Nam Co Salt Lake ZHANG Ge-Jie, HE Jian-Qing 2013, 30 (5):  856-859.  Abstract ( 1524 )   PDF (2202KB) ( 906 )   The quantity, antibacterial activity and species composition of moderatelyhalophilic actinomycetes isolated from the Nam Co Lake, a salt lake in Tibet, were researched. The samples collected from the Nam Co Lake were isolated with 4 isolation media containing 5% and 10% NaCl by dilution plate pouring process. Based on morphological characters, culture characters and cell-wall chemical composition, the strains were preliminarily identified, and the bacteriostasis and enzymatic activity of the isolated actinomycetes were tested. The results show that 36 strains of moderately-halophilic actinomycetes were isolated, in which 26 strains were isolated from soil samples and 10 from water samples. They were identified as Streptomyces, Nocardia, Nocardiopsis and Rhodococcus.The trains were merged into 13 trains based on the morphological characters of the actinomycetes. The results of antibacterial activity experiment showed that there were 4 strains of actinomyces to have a bacteriostatic activity to Fusarium graminearum, Bipolaris sorokinianum and Alternaria alternata, and the antibacterial rate accounted for 30.8%.The restriction activity was the highest to Bipolaris sorokinianum, and the largest antibacterial circle diameter was up to 22 mm. References | Related Articles | Metrics

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Early-warning of Drought Stress for Typical Crops in Urumqi  with Chlorophyll Fluorescence Technique TONG Xiao-Qin, WANG Shu-Zhi, XIA Yong, ZHANG Ye, LIU Yue-Fang, PAN Xiang-Liang 2013, 30 (5):  860-866.  Abstract ( 1554 )   PDF (1659KB) ( 1027 )   The change characteristics of the activity of Photosystem II and I of 4 typical crops (Cucumis sativus L.,Lycopersicon esculentum Mill.,Capsicum annuum L. and Solanum melongena L.) at their seedling stage in Urumqi under drought stress were investigated by chlorophyll fluorescence and absorbance spectroscopy. The relationships between soil moisture content and the photosynthetic parameters were also discussed. The results revealed that, under drought stress, the photosystem performance was dependent on soil moisture content. Fv/Fm and Y(II) were gradually restricted with decreasing soil moisture content, and it was significantly decreased with an occurrence of serious soil moisture deficiency. On the contrary, Y(NO) was gradually increased with decreasing soil moisture content. The potential PSⅡ reaction center activity, Fv/F0, was a promising indicator for distinguishing the tolerance of crops to drought stress and for early-warning drought stress. Soil moisture content had the significant positive correlations with Fv/Fm,Fv/F0, Y(II) and Y(ND),but the significant negative ones with Y(NO) and Y(I). Chlorophyll fluorescence parameters could be used to indicate the physiological status of crops and soil moisture content and to early warn the response of crop seedlings to drought stress. The study results also revealed that there was a difference in tolerance of seedlings of the 4 crops to drought stress. The tolerance of S. melongena L. seedling to drought stress was the highest, then that of C. sativus L. and L. esculentum Mill. seedlings, and that of C. annuum L. seedling was the lowest. References | Related Articles | Metrics

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Stemflow of Haloxylon ammodendron and H. persicum in the Gurbantonggut Desert DAI Yue, ZHENG Xin-Jun, LI Yan, TANG Li-Song 2013, 30 (5):  867-872.  Abstract ( 1338 )   PDF (944KB) ( 1057 )   During the growing season of 2012, Stemflow of two dominant plant species, Haloxylon ammodendrom and H. persicum, was studied in Gurbantonggut Desert, Northwestern China. We firstly selected some trees of the two species to be standard tree and surveyed the size of canopy, and then measured the stemflow after every storm of single precipitation. It was showed that the stemflow both emerged when rainfall lager than 2.4 mm for the two species. It was demonstrated that the stemflow increased with the volume of canopy until larger than 4.0 m3 for H. ammodendrom and 1.5 m3 for H. persicum,respectively. Then, it kept invariant and even began decreasing. There was a significant positive correlation of the two species between the size of single rainfall and the stemflow following. To sum up: the accumulated stemflow volume of the two plants proportioned 9.1% and 6.4% of the total rainfall, respectively. The funneling ratio of the two species both increased with the size rainfall. Consequently, the stemflow of H. ammodendron and H. persicum could be effectively funneled down into the soil around the base of stems to collect water to take up, especially for the former in Gurbantonggut Desert. References | Related Articles | Metrics

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HPLC Fingerprint Chromatogram of Alhagi sparsifolia Shap. MANSUR Sanawar,ABULIZE Alimujiang, ZOU Guo-An 2013, 30 (5):  873-876.  Abstract ( 1107 )   PDF (1270KB) ( 759 )   Alhagi sparsifolia Shap.is a perennial subshrub in the Leguminosae family.It grows mainly in Central Asia and Xinjiang Uygur Autonomous Region,China,and has been used in traditional Uygur medicine for a long time.It is widely used for treating physically weak,dizzy,cold,headache,intestinal constipation and arthrodynia.It mainly contains flavonoids,sterols, alkaloids, fatty acids and polysaccharides.There is no any report on the fingerprint chromatogram or chemical marker of A.sparsifolia yet.In order to develop the fingerprint chromatogram and provide the basis for the effective control of A.sparsifilia quality, the samples were separated by RPHPLC on a Waters Atlantis T3 C18 (4.6 mm×250 mm, 5 μm), with acetonitrile and 0.2% formic acid as mobile phase in a linear gradient manner.The flow rate was 1.0 mL·min-1, the wavelength of detection was 280 nm, and the acquisition time was 100 min.HPLC fingerprint chromatograms of 10 batches of A.sparsifolia were analyzed.The HPLC fingerprint chromatogram of A.sparsifolia was developed with satisfactory resolution and 11 common fingerprint peaks with high similarity of correlation coefficients above 0.9.The peak No.10 and peak No.11 were the main compounds of A. sparsifolia, with the retention time matching isorhamnetin→3→O→β→D→galactosyl→(6→1) →α→L→rhamnoside and isorhamnetin→3→O→β→Drutinoside by HPLC, respectively. The results met the requirements of fingerprint technology. It was identified that the fingerprint method was stable and reliable, and could be used for the quality control of medicinal A. sparsifolia. References | Related Articles | Metrics

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Seed Germination of Picea crassifolia Kom. LIU You-Jun, LIU Shi-Zeng, KANG Cai-Zhou, MAN Duo-Qing, LI De-Lu, LI Yin-Ke 2013, 30 (5):  877-881.  Abstract ( 1276 )   PDF (1382KB) ( 1013 )   Seeds were collected from the natural population of Picea crassifolia Kom. in Tianzhu County, Wuwei City, Gansu Province, China in November 2010. Seed vigor was tested by TTC, the experiments were conducted to investigate the response of seed germination to temperature, light, moisture stress and salinity stress, and some references were finally provided for transplanting P. crassifolia Kom. from Tianzhu to Minqin County. The results are as follows: ① The vigor of P. crassifolia Kom. seeds was 72%; ② Under a complete dark, seeds could not germinate when temperature was lower than 10 ℃, and the optimal temperature for germination was 25/15 ℃ (72%); germination rate of P. crassifolia Kom. seeds under the 24-hour complete dark and 24-hour light were significantly higher than that under 14-hour light and 10-hour dark; ③ Seed germination could be improved when NaCl concentration was 50 mmol·L-1, but it could be restricted when NaCl concentration was higher than 50 mmol·L-1; seed germination could be recovered after salinity stress was removed, the recovery germination rate (RGR) was increased at first and then decreased with the increase of NaCl concentration, and RGR reached its maximum (13%) when NaCl concentration was 400 mmol·L-1; ④ Seed germination was significantly decreased with the increase of PEG-6000 osmotic potential, and seeds could not germinate when the osmotic potential was -0.9 MPa; after PEG-6000 stress was removed, RGR was increased at first and then decreased with the increase of PEG-6000 concentration, and it reached its maximum (35%) when the osmotic potential was -0.9 MPa. References | Related Articles | Metrics

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Regulation of Alkaloid in Ferula Seed Dormancy ABDUXUKUR Yakup, HALIL Kurban 2013, 30 (5):  882-886.  Abstract ( 1443 )   PDF (1111KB) ( 823 )   Some germination inhibiting substances in the endangered herb Ferula fukanensis seeds were studied so as to find the factors affecting seed dormancy based on the following methods: ① Water treatment with germination test; ② Bioassay of water and NaHCO3 leaching liquor; ③ Observation of the effect of Ferula fukanensis seeds on the pH values of the extracting media of distilled water and NaHCO3. The results show that the germination percentages of seeds immersed in water for 5 and 20 days were as high as 77% and 85% respectively, and they were significantly higher than 47% of the contrast seeds (P<0.01). The inhibitory effect of NaHCO3 extract on the germination of wheat seeds was significantly higher than that of H2O (P<0.05). The pH values of the distilled water and NaHCO3 extracts converged in a range of 8.0～8.3 after the Ferula seeds were immersed. The inhibitory effect of alkaloid extract on the germination of wheat seeds was significant, and the inhibition rate could be as high as 80% at a concentration level of 10 g·（100L）-1. It could be concluded that the effect of alkaloid on the regulation of seed dormancy of Ferula fukanensis was very important except abscisic acid. References | Related Articles | Metrics

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Growth and Photosynthetic Pigment Content of Suaeda salsa  Seedlings under Different Salinity and Nitrogen Level YIN Hai-Long, TIAN Chang-Yan, CHEN Chun-Xiu, REN Jing, Huang-Jian 2013, 30 (5):  887-893.  Abstract ( 1433 )   PDF (1308KB) ( 865 )   Growth and photosynthetic pigment content of Suaeda salsa seedlings under different salinity and nitrogen levels were studied by an experiment of potted plant. The results are as follows: ① Moderate applications of nitrogen (0.3 g·kg-1, 0.6 g·kg-1and 1.2 g·kg-1) could promote the growth of S. salsa seedlings under slight, moderate severe salt levels, and the effect of nitrogen application on the growth of S. salsa seedlings was related to the salinity under high salinity and nitrogen levels; ② Under different salinity levels, the highest dry matter yield of S. salsa seedlings, achieved by applying nitrogen, was different, it was in an order of slight salt level (NaCl content of 2.5 g·kg-1) > moderate salt level (NaCl content of 5 g·kg-1) > severe salt level (NaCl content of 7.5 g·kg-1), and the nitrogen productivity was decreased with the increase of nitrogen application; ③ At the same nitrogen level, the leaf osmotic potential of S. salsa seedlings was significantly decreased with the increase of salinity and nitrogen application, and the osmotic regulation capability was increased; ④ At three salinity levels, the photosynthetic pigment content of S. salsa seedling leaves could be increases by applying nitrogen, thus the photosynthetic efficiency could be improved, and the adaptability of S. salsa seedlings to saline or alkaline environment could be increased. References | Related Articles | Metrics

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Effects of Light and Temperature on Leaf Area Index of Wheat in Dryland NIE Zhi-gang, LI Guang 2013, 30 (5):  894-898.  Abstract ( 1600 )   PDF (780KB) ( 1525 )   In order to explore the effect of light and temperature on wheat leaf growth, a regression orthogonal test was firstly designed, and the effects of light and temperature on leaf area index of wheat were simulated using APSIM model. The results showed that APSIM model could be used to simulate the LAI of wheat. There was an upward-opening second-degree parabola between wheat LAI and light but a downward-opening one between wheat LAI and temperature. The second-degree parabola between LAI and light was in a decrease, but the light effect was positive when light was not exceeded the critical value, which revealed that a rational increase of light could promote wheat growth under suitable conditions. The temperature effect was positive when the daily temperature was higher than 7.73 ℃, which revealed that a rational increase of temperature could stabilize the wheat LAI at a high value at a certain growing stage. When both light and temperature were increased, the positive effect of light was more significant than that of temperature. References | Related Articles | Metrics

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Granularity Effect in Analyzing Landscape Patterns  in the Guanzhong-Tianshui Economic Zone FENG Xue-Ming, LI Jing, ZHANG Dong-Hai 2013, 30 (5):  899-904.  Abstract ( 1177 )   PDF (1684KB) ( 1090 )   Based on the data of TM images in 2010, The Guanzhong-Tianshui Economic Zone was divided into 6 landscape types using the ArcGIS software and Erdas software. The Fragstats 3.3 spatial analysis program was used to study the granularity effect of landscape pattern indices from the landscape types by selecting the area proportion of plots, number of patches, largest patch index, landscape shape index, mean fractal dimension of patches and connectivity index, and the fitting functions were analyzed. The results showed that there were 4 kinds of change trends of landscape pattern indices under a granularity range of 30-600 m:① The exponent value was basically unchanged;② The exponent value was regularly increased or decreased with an obvious inflection point;③ The exponent value was regularly increased or decreased without an obvious inflection point;④ The index changed irregularly; the response curves of landscape pattern indices to granularity could be fitted with cubic function and linear function separately. In the Guanzhong-Tianshui Economic Zone, the suitable granularity ranges for computing [JP2]and analyzing the landscape indices were 120 m for cultivated land, 120-160 m for forest, 90-130 m for grasslands, 90-110 m for waters, 90-130 m for construction land, and 110-160 m for unused land, respectively. References | Related Articles | Metrics

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Ecological Footprint and Its Application in Ecological  Planning in Kashgar Prefecture BA Wu-Long, ZHOU Hua-Rong, LIANG Xue-Qiong, LI Yu-Xia 2013, 30 (5):  905-912.  Abstract ( 1536 )   PDF (2076KB) ( 903 )   Ecological footprint is a method to quantitatively measuring the utilization degree of natural resources. In this paper, the theory, calculation methods and calculation models of ecological footprint were used to calculate, predict and analyze the dynamic change process of ecological footprint in Kashgar Prefecture, Xinjiang, China during the period from 2000 to 2009. The results showed that the development in Kashgar Prefecture was unsustainable. It was predicted that the per capita ecological footprint under the traditional development mode in Kashgar in 2016 would be up to 2.86 hm2. and 14 times of that in 2000. The pressure on ecological environment, caused by ecological footprint, was quite different from different regions in Kashgar, and the sustained increase in consumption of agricultural products was the main reason of expanding the ecological footprint. The ecological security in Kashgar was assessed based on calculating the ecological footprint and analyzing the distribution pattern of ecological footprint in Kashgar, and the application of the ecological footprint theory in ecological planning in arid area was discussed. References | Related Articles | Metrics

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Vertical Distribution of Soil Organic Carbon in Different Land  Cover Types in Northern Piedmont of the Tianshan Mountains WANG Yuan-Gang, LUO Ge-Ping, FENG Yi-Xing, LI Chao-Fan, HAN Qi-Fei, FAN Bin-Bin 2013, 30 (5):  913-918.  Abstract ( 1696 )   PDF (921KB) ( 1023 )   Soil carbon cycle is the focus and hotspot of the studies on global environment change. Relationship between the vertical distribution of soil organic carbon and its affecting factors was explored, especially in arid zone. In this study, the vertical distribution of soil organic carbon under different land cover types in northern piedmont of the Tianshan Mountains was studied based on the data of second national soil survey. The results showed that the mean soil organic carbon density in soil layer of 0-100 cm in depth varied from 3.65 kg·m-2in land with sparse vegetation to 35.73 kg·m-2in alpine and subalpine meadow. The vertical distribution of soil organic carbon density was quite different from different land cover types: the proportion of soil carbon density in soil layer of 0-20 cm in arable land accounted for 32.2% of the total soil carbon density in topsoil layer of 1 m in thickness, it was higher than 40% in alpine and subalpine meadow, forest and intrazonal vegetation surface, and lower than 37% in desert vegetation and bare land and land with sparse vegetation, in which it was 25.4% only in bare land and land with sparse vegetation. The average difference of soil carbon density between adjacent soil layers was lower than 8.1% in arable land and lower than 4.0% in bare land and land with sparse vegetation. References | Related Articles | Metrics

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Glacier Change in Headwaters of the Yangtze River in Recent Three Decades XU Jun-Li, ZHANG Shi-Qiang, SHANG Guan-Dong-Hui 2013, 30 (5):  919-926.  Abstract ( 1549 )   PDF (1877KB) ( 1340 )    Many researches have shown that most glaciers in the world experienced a general reduction in area due to climate warming in recent decades. The glaciers in headwaters of the Yangtze River in the central-northeast part of Qinghai-Tibetan Plateau are mainly distributed in the north-oriented slopes of Mt. Tanggula and Mt. Sedir and the south-oriented slopes of Mt. Kunlun. In this study, the change of glaciers in the whole headwaters was monitored using the 1∶100 000 topographic maps based on the aerial photographs taken in 1969/1971 and the Landsat ETM+ imageries in 1999/2002. Moreover, Landsat MSS (1973), Landsat TM (1992) and 2 scenes 2005 and 2006, ASTER images at level 1B, were used to study the change of glaciers in the Geladandong Peak area in multi-periods. It was found that the most glaciers in the headwaters were in a retreat. In general, the glaciers were retreated by 108.3 m in average, and an area of 68.13 km2 was lost, accounting for 5.3% of the total glacier area. There was a significant difference in glacier change rate among the Mt. Tanggula, Mt. Sedir and Mt. Kunlun. Shrinkage of area of the glaciers was 12.9% in the Mt. Sedir, 4.3% in the Mt. Tanggula, and 8.3% in the Mt. Kunlun respectively. The results of glacier change in the Geladandong Peak area in multi-periods showed that the reduction of glacier area was the most significant during 1969-1973, about -1.16 km2·a-1, and the glacier area was enlarged by 0.59 km2·a-1during 1973-2002. However, the reduction of glacier area was accelerated after 2002 with a change rate of -0.95 km2·a-1. Generally, the larger the glacier area was, the lower the glacier change rate would be. According to the statistic analysis, there was a decreasing logarithm relationship (R2=0.91)between the glacier area and the area reduction rate in the study area. The meteorological data observed by Zhiduo, Tuotuohe and Wudaoliang Glacier meteorological stations revealed that the retreat of glaciers in this area may be mainly caused by the increase of air temperature in warm season, and the different extent of temperature increase may be one of the reasons resulting in the different glacier change rate among the Mts. Tanggula, Mt. Sedir and Mt. Kunlun. References | Related Articles | Metrics

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Variation of Runoff Volume of Mainstream of the Tumen River XU Wan-Ling, MAN Wei-Dong, ZHU Wei-Hong, QIN Lei, CAO Guang-Lan 2013, 30 (5):  927-932.  Abstract ( 1452 )   PDF (1571KB) ( 1124 )   The nonparametric Mann-Kendall method was used to detect the longterm trends and determine the significant level of annual runoff volume observed at the hydrological stations in mainstream basin of the Tumen River. The R/S analysis was applied to analyze the sustainability of annual, seasonal and monthly runoff volume, on which the Mann-Kendall test was used to examine the future trend of annual runoff volume. The results showed that there was generally a reduction trend of annual, seasonal and monthly runoff volume, the reduction of annual runoff volume was mainly caused by the reduction of runoff volume in spring and winter. The Hurst exponent indicated that the annual runoff volume was holistically decreased, and a continuous decrease may be maintained in the future. The sustainability of change trend of runoff volume was the highest in the upper reaches but the lowest in the lower reaches. The MannKendall change-point test method was used to determine the time series of hydrological change points of annual runoff volume. Results indicated that the hydrological change point occurred in 1985. At the same time, the annual precipitation in the mainstream basin of the Tumen River was also changed, so it was inferred that the decrease of precipitation may be an important factor resulting in a reduction of surface runoff volume in the mainstream basin of the Tumen River. References | Related Articles | Metrics

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The Variation of Runoff Volume and Sediment Load and Its Driving Factors  in Huangfuchuan River Watershed MU Xing, ZHANG Xiao-Ming 2013, 30 (5):  933-939.  Abstract ( 1413 )   PDF (2468KB) ( 969 )   Huangfuchuan River watershed is located in the rich and coarse sand area in the middle reaches of the Yellow River. The variation of runoff volume and sediment load in this area has an indicating significance to the change of watersand regime in the lower reaches of the Yellow River. In this study, the typical periods of the variation of runoff volume and sediment load have been ascertained by double cumulative curve and the variation trend of runoff volume and sediment load has been analyzed in the Huangfuchuan River watershed. In addition, the driving factors of the variation of runoff volume and sediment load have been analyzed considering the soil and water conservation measures since the 1950s. The results show that the evolution process of runoff volume and sediment load could be divided into four typical periods, i.e., 1954 to 1978, 1979 to 1987, 1988 to 2002 and 2003 to 2010. During the period from 1954 to 1978, the watershed was slightly affected by human activities and its control degree was low; therefore this period is called natural variation period. The effects of runoff volume and sediment load reduction resulted from soil and water conservation measures have been increasing in the period of 1979 to 2010. The effect of runoff volume reduction reaches to 41.8% and the effect of sediment load reduction reaches to 49.7% by double mass curve method. The values are respectively 44.7% and 48.3% by runoff/sediment coefficient method. References | Related Articles | Metrics