Table of Content

15 September 2015, Volume 32 Issue 5 Previous Issue    Next Issue

Ecology and Environment in Central Asia

Select

Spatial-temporal Variations of Precipitation and Temperature in Tajikistan LI Wei, WU Yan-feng, Batur Bake, WEI Xiao-qin, Hamid Rasulov 2015, 32 (5):  835-844.  doi: 10.13866/j.azr.2015.05.01 Abstract ( 993 )   PDF (2549KB) ( 952 )   This paper analyzes the spatial-temporal variations of precipitation and temperature using the data from 46 meteorological stations from 1971 to 2013 based on the methods of EEMD,trends analysis and wavelet analysis. The results showed that:① In temporal variations,the annual precipitation and average temperature all have increasing trend,annual precipitation presented periodicities of 3 a,6 a,14 a and 27 a,and temperature presented periodicities of 3 a,7.5 a,12-13 a and 32 a,respectively. ② In spatial variations,the annual precipitation was significantly increased at the tendency rate of 15.2 mm·(10a)-1,and the distribution characteristics of average annual precipitation were gradually reduced from the central to the borders. The change trend of seasonal precipitation presented significantly difference,at the rate of -1.7 mm·(10a)-1 (spring),1.3 mm·(10a)-1 (summer),1.1 mm·(10a)-1 (autumn) and 4.4 mm·(10a)-1 (winter),respectively. There was a decadal variation of precipitation: the annual precipitation was relatively low in the 1970s,kept increasing in the 1980s and 1990s,and achieved the maximum in the 2000s. The annual average temperature was significantly increased (average temperature tendency rate is 0.26 ℃·(10a)-1 and the tendency rate gradually increased from the south to north. The seasonal average temperature all showed increasing trend and the order of increasing from stronger to weaker is winter,spring,autumn and summer. The temperature experienced a period of “low-high-low-high” in the decadal variations; the average temperature was relatively low in the 1970s and 1990s,relatively low in the eastern but high in the western in 1980s,and relatively high in 2000s,and the average temperature from 2000 to 2013(0.4-0.7 ℃) is higher than that from 1971 to 2013. ③ The temperature and precipitation presents obvious resonance negative correlation in Tajikistan. References | Related Articles | Metrics

Select

A New Record Genus and One New Record Species of Ormyridae (Hymenoptera: Chalcidoidea) from Kyrgyzstan TANG Xiu-li, Zhulidezi Aishan, WANG Chao, Li Qin, HU Hong-ying 2015, 32 (5):  845-848.  doi: 10.13866/j.azr.2015.05.02 Abstract ( 762 )   PDF (645KB) ( 648 )   Ormyrus is by far the largest genus and the only one to occur in the Palaearctic region of the family Ormyridae (Hymenoptera: Chalcidoidea). Species of Ormyrus are mostly solitary,larval,primary ectoparasitoids of gall inducing Cynipidae (Hymenoptera) and Cecidomyiidae,Tephritidae and Agromyzidae (Diptera),so they can be important biological control agents of gall-former insects. In this paper,Ormyridae resources in Kyrgyzstan was investigated for the first time,as a result,one newly recorded genus Ormyrus (Westwood) and one newly recorded species Ormyrus yeschilirmaka Doganlar from Kyrgyzstan is described and illustrated,which will provide the base data for biological control of gall-former pests in Kyrgyzstan. All the specimens studied are deposited in the Insect Collection of College of life Science and Technology,Xinjiang University,Urumqi,Xinjiang,China [ICXU].Through comparing this with the Ormyridae resource in Xinjiang and even in China,the study has very important theoretical and practical significance to know the origin and evolution of Ormyridae within the animal geographical flora in the world and resources protection and reasonable development and utilization of Ormyridae. References | Related Articles | Metrics

Soil Environment

Select

Microbial Community Structural Change in Northeastern Tibetan Plateau SI Gui-cai, WANG Guang-peng, LEI Tian-zhu, ZHANG Geng-xin, XIA Yan-qing, CHEN Fang-rong 2015, 32 (5):  849-855.  doi: 10.13866/j.azr.2015.05.03 Abstract ( 699 )   PDF (1298KB) ( 778 )   Soil microbial response to climate change will affect the whole ecological process,and represent many uncertainties feedback of ecosystem to climate change. Six sample sites and two soil depths (0-5 cm,5-10 cm),a total of twelve samples were collected along a mean annual precipitation (MAP) gradient in arid and semi-arid,northeastern of Tibetan Plateau and PLFA technology was used to analyze microbial community structure and total microbial biomass. These results showed that total organic carbon and total nitrogen were significantly declined with the MAP decreasing,which was also found in bacteria,fungi,actinomycete biomass. However,microbial biomass had an increased trend in the extreme arid area. Person correlation analysis and Canonical Correspondence Analysis showed that both in 0-5 cm and 5-10 cm soil depth,MAP had a significant correlation with soil physicochemical properties and soil microbial biomass indicate that MAP was a key factor in soil microbial community structure in arid and semi-arid area,which was more significant in 0-5 cm soil depth. The study will provide theoretical basis for further studies of soil microorganisms' response to the water landscape change in the background of global climate change in arid zone. References | Related Articles | Metrics

Select

Comparison of Microbial Total DNA Extraction Methods from Saline-alkali Soils in Hexi Corridor LI Hai-yun, NIU Shi-quan, KONG Wei-bao, WANG Bei, DA Wen-yan 2015, 32 (5):  856-860.  doi: 10.13866/j.azr.2015.05.04 Abstract ( 772 )   PDF (650KB) ( 693 )   Due to soil microbial community structure and diversity and their change to a certain extent reflect the quality of the soil,the saline soil microbial diversity and population structure have certain application value for saline soil improvement. Saline soil is a special kind of soil type,may be a lot of salt resistance,alkali resistance and halophilic extremophiles groups,and has great development and utilization value,can build saline soil microbial macro gene pool,and screen out useful genetic resources used by mankind. To establish a method of total DNA extraction for investigation of the microbial population structure and diversity at saline-alkali soil in Hexi corridor,four kinds of methods that are M1(Omega kit method ),M2(MoBio kit method ),M3(modified high-salt method) and M4(Calcium chloride-SDS-Enzymatic) were used. The results showed that: 23.1 kb DNA fragments were obtained by the methods,and no DNA degradation. But the DNA extraction results were very different between the 4 methods,M1 and M2 shows no clear bands but high pure DNA; M3 and M4 obtain higher DNA amount than M1 and M2,however,the DNA obtained by M3 has more impurities which affects the accuracy of subsequently analysis. The DNA purity by M4 are more approximate to the kit method,the amount of DNA extraction reached 452.875 μg·g-1,much higher than the other 3 kinds of methods,more suitable for the subsequent experiments. The results indicated that M4 is suitable for total DNA extraction to study microbial abundance and diversity from saline-alkali soil in Hexi Corridor. References | Related Articles | Metrics

Select

Effects of Straw Mulch on Vertical Water Movement and Evaporation of a Soil Column ZHANG Jin-zhu, WANG Zhen-hua, Hudan Tumaerbai 2015, 32 (5):  861-868.  doi: 10.13866/j.azr.2015.05.05 Abstract ( 683 )   PDF (1406KB) ( 849 )   To investigate the effects of straw mulch on soil water evaporation,indoor soil column evaporation experiments were carried out. The straw layer of two positions (soil surface and 20 cm below soil surface),4 application amount [0 (CK),6 000,12 000,and 18 000 kg·hm-2],and 3 straw lengths (1,5 and 10 cm) were evaluated for their effects on soil water evaporation. Results showed that surface application could significantly inhibit water evaporation. The more the straw was applied,the smaller the daily evaporation intensity was. There were significant differences in cumulative evaporation between treatments with different application amount. Straw length did not show a significant effect on daily evaporation intensity. There were significant differences in cumulative evaporation between treatments with different straw lengths when straw was applied at 18 000 kg·hm-2. The treatments with straw applied at 20 cm below soil surface had higher daily evaporation intensity than surface application treatments and CK at early stage of evaporation,but had lower than the above two treatments at later stage of evaporation. The cumulative evaporation was significantly different between treatments with different application amount when the straw length was 1 cm or 10 cm. And the cumulative evaporation was significantly different between treatments with different straw lengths when application amount was 12 000 or 18 000 kg·hm-2. Statistical analysis revealed that straw application amount exerted the greatest effect on cumulative evaporation when straw was surface applied,while straw length had a significant effect on cumulative evaporation when straw was applied at 20 cm below soil surface. References | Related Articles | Metrics

Select

Influence of Lucerne Field Growth Years on Nitrous Oxide Emission at the Loess Plateau LI Yuan, WANG Tao, SHEN Yu-ying 2015, 32 (5):  869-874.  doi: 10.13866/j.azr.2015.05.06 Abstract ( 670 )   PDF (2376KB) ( 836 )   Nitrous oxide (NO2) is a major atmospheric greenhouse gas. The soil physical properties and fertility will directly affect the production and release of NO2. Alfalfa has the advantages to improve soil physical properties and fertility,and the soil physical and chemical properties variation degree is associated with fixed the number of alfalfa planting years. A static chamber-HPLC method was used to detect NO2 emission fluxes in the fallow field,3,4,and 10 years-aged lucerne (Medicago sativa) field at the Loess Plateau. In addition,the DeNitrification-DeCoposition (DNDC) model was also applied to estimate the NO2 emission variations in our study,which fit pretty well with the measured NO2 emission fluxes. Compared to the fallow field,observed values of the N2O emission increased with the ages of lucerne field. Interestingly,the detected negative NO2 emission values in our analysis were disparate with the model calculations. The time of released NO2 from differently aged lucerne field fluctuated and accumulated highly between 170-240 days during the growing season,the most release was estimated at 210 day in the DNDC model. Although the DNDC model could estimate the NO2 emission fluxes in lucerne field at the Loess Plateau,further parameter modifications are required to include the negative flux emissions in the analysis. References | Related Articles | Metrics

Select

Species Diversity of Haloxylon ammodendron Community and Its Correlation with Soil Characteristics XU Lei, LIAO Fan, YAN Cheng, YANG Geng-qiang 2015, 32 (5):  875-881.  doi: 10.13866/j.azr.2015.05.07 Abstract ( 747 )   PDF (2127KB) ( 768 )   Species diversity is a measure of community structure and functional complexity,and the species is a basic unit of the species diversity and the most important measure of species diversity. In the natural community species composition and the structure is the result of the long-term adaptation to the environment. Haloxylon ammodendron community is a major plant community at periphery area of Karamay,species diversity level is not high and the community structure is single. Choosing four sample areas,we had investigated Haloxylon ammodendron community species diversity,and analyzed the correlation between four species diversity index with soil characteristics at periphery area of Karamay. The result as follows:① Shannon-Wiener diversity index,Gleason richness index,Pielou evenness index first increases then decreases from piedmont frontier to the desert,Simpson dominance index first decreases then increases;② There are differences in soil layers pH value,soil total salt content,and ion content of K+,Cl-,SO2-4,Ca2+ at different sample areas. Variation of pH value was small,soil total salt content shows clay>alluvial fan gravel desert>pluvial gravel desert>desert. Other salt ions show that the same trend with soil total salt content. ③ According to the result of multiple liner regression between diversity index and soil characteristics at different layers,soil index had certain correlation with diversity index at different layers,pH value,soil total salt content and ion content of K+,Cl-,SO2-4,Ca2+ had main influence on the diversity index,while ion of HCO-3 is lower. The study result could provide the theory basis for urban peripheral damaged vegetation restoration and biodiversity protection in Karamay City. References | Related Articles | Metrics

Soil and Soil Conservation

Select

Research on the Ecological Benefits of Soil Conservation of Yulin City Based on InVEST Model LI Ran 2015, 32 (5):  882-889.  doi: 10.13866/j.azr.2015.05.08 Abstract ( 1059 )   PDF (3608KB) ( 788 )   As is well known to all that water and soil loss is the most serious ecological problems in the Loess Plateau, so it is of great significance to evaluate ecological benefits of soil conservation. Taking Yulin as an example, InVEST model was used to evaluate ecological benefits of soil conservation of Yulin city from 2000 to 2010 in the paper. And its evolution law and spatial pattern characteristics has been found. The results showed that: ① From 2000 to 2010, it has showed that the soil conservation quantity increased firstly and then decreased, and the soil conservation ecological benefit had a declining trend. For the annual mean soil conservation ecological benefits, it had more than 1.19×1011 billion yuan. Both soil conservation quantity and soil conservation benefits, Shenmu County was the biggest, and Wubu County was the minimal. ② The soil conservation ecological benefit space distribution in Yulin exhibited a decreasing trend from northwest to southeast and the value of river upstream and midstream is higher than downstream. The value of northern six counties was much higher than that of southern counties. ③ Soil conservation quantity and its ecological benefit had obvious difference, which difference may attribute to several factors as topography, land-use pattern, soil physical and chemical properties, ecosystem type and vegetation cover, as well as land area. Especially, the size of the land area had a great effect on both the total soil conservation quantity and soil conservation ecological benefit. That was why the total of the six counties in the south was smaller than north. References | Related Articles | Metrics

Select

Inversion of Spatial Distribution Pattern of Topsoil Total Nitrogen Contents in Sanjiangyuan Regions Based on OLI Images JIA Wei, GAO Xiao-hong, YANG Yang, ZHANG Wei, YANG Ling-yu, TIAN Cheng-ming 2015, 32 (5):  890-896.  doi: 10.13866/j.azr.2015.05.09 Abstract ( 857 )   PDF (1441KB) ( 930 )   In this paper,taking Yushu county, Chengduo county and Maduo county in Sanjiangyuan Regions as a case, the Landsat 8 OLI image was used to predict the spatial distribution pattern of topsoil total nitrogen contents. The spectrum reflectance ( R) and its two kinds of transformation forms, including the spectrum reflectance reciprocal (1/ R) and the logarithm of spectrum reflectance reciprocal [lg(1/ R)],selected to relate to soil total nitrogrn measured in laboratory. Firstly, correlation analysis between above three spectral index and the measured topsoil (0-30 cm) total nitrogen was conducted. Secondly, according correlation analysis results, the spectral index with the highest correlation was selected. In the end, the regression models were established using principal component with significant levels of correlated bands. The results show that the spectral reflectance and its two transformation forms from B1-B4, B7 were significantly correlated levels with the measured data, in which the lg(1/ R) was the most obvious. The negative quadratic polynomial model was set up through the first and second principal components of lg(1/ R) of these five bands, in which the R2 of calibration model R2 was 0.621, RMSE was 2.075, validation samples R2 was 0.730, RMSE was 1.493 and RPD was 1.849, suggesting the predicting model having a high precision, good stability. Therefore the OLI images could be used to estimate the spatial distribution pattern of topsoil total nitrogen better. References | Related Articles | Metrics

Select

Study on the Soil Spatial Variability of Ulmus pumila Open Forest in Horqin Sandy Land SHI Yu-fei, JIN Yong-huan, JIN Lan-shu, SONG Zhu-fu 2015, 32 (5):  897-902.  doi: 10.13866/j.azr.2015.05.10 Abstract ( 678 )   PDF (2075KB) ( 674 )   In order to ascertain the distribution rules of the Horqin sand soil with Ulmus pumila open forest after Grain for Green,this paper uses geostatistical methods to analyze the correlation,spatial variability and distribution of soil properties in Wusitu natural reserve area of eastern Horqin with Ulmus pumila open forest. The results show the spatial variability of soil pH is weak,but the soil total nitrogen,the soil organism,soil available N and available P have a medium spatial variability. If using the theoretical model of the GS+ and software automatically fitted variation function,the soil pH is spherical model,the soil total nitrogen and organism are linear model,the soil available N is exponential model,and the soil available P is Gaussian model. The soil total nitrogen and organism demonstrate a pure nugget effect with a constant spatial variability at a small scale. The pure nugget effect is only influenced by the stochastic factors not by the structural factors,and it has little obvious variation rules. However,the ratio of the soil pH,the soil available N and the soil available P is less than 25% with a strong spatial relevance. The random part caused little spatial variability. Only except the available nitrogen,the other four soil properties are uniform in spatial distribution. Therefore,it can infer the available nitrogen may be the critical element of the ecological restoration here. After the human’s destruction for a long time in history,the restoration of land vegetation and soil nutrient are not synchronous. The latter is slower than the former. So the recovery of Ulmus pumila open forest grassy ecosystem requires a long-time closing hillside to facilitate afforestation. References | Related Articles | Metrics

Select

Experimental Study on Carbon Leaching during Irrigation in Arid Areas XIE Huai-liang, WANG Yu-gang, LI Yan 2015, 32 (5):  903-909.  doi: 10.13866/j.azr.2015.05.11 Abstract ( 698 )   PDF (2120KB) ( 882 )   The transfer of carbon in the hydrologic cycle is one of the hot-point issues to address climate change,and an important component of global carbon budgets,understanding the significance of soil carbon processes can enhance development of strategies to mitigate atmospheric carbon concentrations. In order to quantify the contribution of field irrigation to dissolved carbon transfer in arid areas,a leaching experiment on soil column to simulate irrigation was carried out. This study measured organic and inorganic carbon leaching loses from different soil (gray desert soil and oasis farmland soil) with different crops (spring wheat and rice) to explore the organic and inorganic carbon transport mechanism under different irrigation manners. Each soil type had 10 experiments with spring wheat and rice,respectively. Moreover,there were 3 soil columns without any crops. In the first period,the amount of organic and inorganic carbon was highest. As the change of seasons and the growth of crops,the water consumption increasing gradually reduced the amount of organic and inorganic carbon leaching; in the salt desert,organic carbon leaching account for percent 54 to 63.1 of the total carbon leaching,higher than inorganic carbon. However in the farmland,inorganic carbon leaching accounted for percent 68.6 to 83.7 of the total carbon leaching,much larger than organic carbon; Rice cultivation has higher amount of irrigation,so organic and inorganic carbon leaching is higher than spring wheat; Spring wheat cultivation patterns,organic and inorganic carbon leaching from the soil of salt desert were higher than farmland soil; Rice cultivation patterns,organic carbon leaching from salt desert was also higher than farmland soil,but the amount of inorganic carbon leaching was higher in farmland soil than salt desert soil; Organic and inorganic carbon leaching of cultivation spring wheat soil was higher than contrast (P<0.05),however,growing rice have no significant difference with contrast (P>0.05). The results showed that soil type,crop type and amount of irrigation has a significant effect on soil organic carbon and inorganic carbon leaching. References | Related Articles | Metrics

Select

Study on Soil Aggregates of the Desert Highway Shelterbelt in Tarim SHEN Fang-yu, WANG Yong-dong, LI Sheng-yu, XU Xin-wen, ZHAO Rong-huai, JIA Meng-meng 2015, 32 (5):  910-917.  doi: 10.13866/j.azr.2015.05.12 Abstract ( 681 )   PDF (1047KB) ( 858 )   In order to understand the composition and stability of soil aggregates of Desert Highway shelterbelt in Tarim,soils of 0-20 cm in 5 different planting age’s shelterbelt were analyzed through field sampling and laboratory analysis. Dry sieving method and wet sieving method were used in this study. The results showed that: ① Under the condition of dry sieve,the content of >0.25 mm air drying soil aggregates is between 33.35-280.38 g·kg-1 in different layers,and the >5 mm aggregate is predominant in different layers,about 41.56%-70.09%; the 5-2 mm aggregate comes second,about 6.58%-34.88%,the 1-0.5 mm aggregate content was the lowest,only 1.66%-5.46%. Under the condition of wet sieve,the content of >0.25 mm water-stable aggregates is between 0.21-72.54 g·kg-1 in different layers,and the change of soil aggregates decreased with the decreasing of particle size for all planting age’s shelterbelt. ② With the increasing of shelterbelt planting years,the content of air drying soil aggregates increased from 69.94 g·kg-1 to 159.88 g·kg-1,and the content of water-stable aggregates increased from 0.41g·kg-1 to 60.84 g·kg-1 in 0-20 cm soil layer,while there is no aggregate formation in quicksand. Shelterbelt plantation promoted the formation of aeolian sandy soil. ③ With the increasing of planting years,the content of >0.25 mm air drying soil aggregates (SDA>0.25 mm) and water-stable aggregates (WSA>025 mm),mean weight diameter (MWD) and geometric mean diameter (GMD) of soil aggregates increased,and the correlation between these parameters are significant (P<0.01). ④ The content of >2 mm air drying soil aggregates can be used to characterize the mechanical stability of soil aggregates in the shelterbelt soil; and the content of >1 mm water-stable aggregates can be used to characterize the water-stability of soil aggregates in the shelterbelt soil. Planting shelterbelt on aeolian sandy soil along Tarim Desert Highway could increase the formation of soil aggregates,promote the aggregates to be well-distributed and improve the mechanical stability and water-stability of soil aggregates,and accelerate the soil forming process. References | Related Articles | Metrics

Select

Study on Changing Trend of Soil Erosion in Yulin City from 2001 to 2010 LI Bo-yan, REN Zhi-yuan, YI Lang 2015, 32 (5):  918-925.  doi: 10.13866/j.azr.2015.05.13 Abstract ( 726 )   PDF (1735KB) ( 742 )   With the development of global social economy,the unreasonable development and utilization of natural resources of human lead to serious soil erosion and soil erosion has become one of the world's focus on environmental issues. Soil erosion plays an important role in soil water conservation,desertification control,is of the great significance in regional soil and water resources development,protection and utilization. Using the universal soil loss equation as the tool,by the grid technology,spatial interpolation and analysis,linear regression techniques,we conduct sample,reclassification,and spatial statistical analysis of raster data; analyze soil erosion dynamic changes and its distribution of Yulin city for 10 years,and predict soil erosion trend in future. Research shows that: ① The soil erosion average module is generally smooth in Yulin city from 2001 to 2010,but there are jumpy inflection points in 2003 and 2009,the minimum value in 2003 and the maximum value in 2009; ② The total soil erosion area is increasing year by year in Yulin City,the mild,moderate soil erosion area proportion in increasing,especially the moderate erosion above percent 21.68 of the total area,the light soil erosion area accounting for percent 37.91 of the total area;③ The soil erosion of industrial land and energy development zone is more serious; ④ In the next few years soil erosion would mainly occur in most parts of Fugu,in the central part of Shenmu and Dingbian,part of energy zone and its surrounding,etc.Through the calculation of the amount of soil erosion,the soil erosion prediction will provide the scientific basis and decision support for the prevention and protection of soil and water loss. References | Related Articles | Metrics

Plant Geography

Select

Floristic Analysis of Vascular Plants of Baerluke Mountain in Xinjiang Bahejiayinaer Tiemuerbieke, MA Jian-ying, Nuerbayi Abudushalike 2015, 32 (5):  926-933.  doi: 10.13866/j.azr.2015.05.14 Abstract ( 644 )   PDF (1003KB) ( 491 )   There is rich biodiversity and special geographical position in Baerluke Mountain in Xinjiang. In this paper,we analyzed the flora composition and geographical composition of Baerluke Mountain in detail,and briefly described the endemic and rare and endangered species in this flora. Results indicate: there are three biggest families in Baerluke Mountain,which are Asteraceae,Poaceae and Fabaceae,including 424 species,accounted for percent 32.6 of the total of the species in the mountain. In the distribution area type of families,the Cosmopolitan distribution area type is the biggest one,including 42 families,accounted for percent 28.9. In the distribution area type of genera,the North Temperate distribution area type is the dominant one,including 178 genera,accounted for percent 38.6. In the distribution area type of species,the temperate elements are dominant; among them the Old World Temperate distribution area type is the most widespread one,including 297 species. The second large component of this flora is Tethyan species,most of them are the mutual species for both Kazakhstan flora and Zhungaer flora,and this means study area is the confluence of Iran-Turan flora and Zhungaer flora. In addition,being the bridge between Siberian (Altai) and Tianshan flora from north to south,study area was the border for some species of these two big floras. There are over 50 species listed into the rare and endangered species in study area,and 6 species endemic to Baerluke Mountain. The study could provide basic data for the protection of wildlife in this area,environmental protection and nature reserve,the promotion national protected areas. It is of great practical significance to protect nature reserve,the original ecology,the rare and endangered flora composition in Baerluke Mountain. References | Related Articles | Metrics

Select

Relation between Geographic Distribution of Calligonum mongolicum and Climatic Factors LIU Na, FENG Ying, GUAN Kai-yun, FAN Yong-qing, YANG Geng-qiang 2015, 32 (5):  934-940.  doi: 10.13866/j.azr.2015.05.15 Abstract ( 670 )   PDF (822KB) ( 647 )   Under the background of global climate change,much attention has been paid to the study of the relationship between vegetation and climate,climate restricts the geographical distribution of vegetation and vegetation types reflect the climate characteristics. The plants adapt to climate,at the same time,have feedbacks to the climate. On the basis of field investigation and checking floras and the specimens preserved in herbaria,the detailed geographic distribution data (including the distribution map) and botanical data of Calligonum mongolicum; were provided here. Then the relation between its geographic distribution and climate factors was analyzed with Kira’s warmth index and coldness index,Xu’s humidity index,annual mean precipitation,annual mean sunshine hours,annual mean wind speed and other climate indexes. The results showed that ① In the distribution area of Calligonum mongolicum,its average annual biological temperature was 6-13 ℃,warm index was 41-143.8 ℃·mon,cold index was -31.2--53.9 ℃·mon,the extreme high temperature was 47.7 ℃and the extreme low temperature was -41.6 ℃,average annual temperature was 2.2-14.4 ℃,annual temperature range was 49.9 ℃,frost-free period was 80-225 d,sunshine time were 2 700-4 440 h,humid index was 0.1-5.2 mm·(℃·mon)-1,potential evapotranspiration was 393.3-738.3 mm,average annual precipitation was 13.8-230 mm which had a bigger range,and its average annual wind speed was 1-4.8 m·s-1. Besides,Calligonum mongolicum; was a plant growing in temperate or warm temperate,arid and semi-arid areas with high temperature,long sunshine time and high annual range; ② Principal component analysis showed that relative effect of climate factors on the distribution of Calligonum mongolicum were,temperate factor>low temperate factor>sunshine factor > wind speed factor. References | Related Articles | Metrics

Select

On the Relationships between Intra-annual Variation of Ephemeral Synusia and Hydrothermal Conditions YUAN Su-fen, TANG Hai-ping, ZHANG Hong-feng 2015, 32 (5):  941-946.  doi: 10.13866/j.azr.2015.05.16 Abstract ( 652 )   PDF (1264KB) ( 1308 )   Ephemeral plant (Ephemerals) is generic terms a kind of plant group with very short life cycle or growth cycle and the growth cycle is 2 months or so commonly,then part or the whole plant dry dead on the ground and have a bad season in the form of components in below ground organs of dormant seeds. Ephemerals,including annual ephemerals and ephemeroids,are characterized by short-term growth rhythms and specific biological traits adapted to deserts or temperate broad-leaved deciduous forests. Few studies have been carried out on ephemeral community composition and their relationships with temperature and precipitation regimes in the desert. In 2008,we monitored the early-spring ephemeral community change in the Mosuowan area of the Junggar Desert,northern Xinjiang. We also collected temperature and precipitation data to analyze the effects of these factors on ephemeral adaptation. It turned out that the time and amount of the first rainfall were the important factors to determine the time of the germinating,and the precipitation status after seedling had significant effect on the community physiognomy in the current year,while the emergence time of hot-dry season determined the life cycle of the ephemerals. Additionally,Ephemeral plant has a special growth phenomenon with vegetative growth and reproductive growth over the same period,the growth and development of ephemerals showed a very high sensitivity and adaptability to the variations of hydrothermal conditions,especially to the precipitation that appears occasionally. Ephemeral plant “a race against time” growth has high consistency with the water hot configuration. References | Related Articles | Metrics

Select

Root Sucker Propagation of Wild Prunus divaricata in Different Micro-habitats in Xinjiang,China ZHAO Yu, LIU Ying, SHANG Tian-cui, LIU Bo 2015, 32 (5):  947-952.  doi: 10.13866/j.azr.2015.05.17 Abstract ( 814 )   PDF (1951KB) ( 781 )   The characteristics of clonal propagation and the seedling regeneration from root suckers of wild Prunus divaricata in four habitats were studied in this research. The result indicated that the density of the younger sprouting seedlings of Prunus divaricata in gully habitat was the highest; the following were forest floor,steep slope and gentle slope,successively. There were five age classes of sprouting seedlings,the proportion of seedlings reduced with increase of age class in different habitats. And the proportion of sprouting in steep slope habitat was the highest,and others successively were in sequence of forest floor,gully and gentle slope. The sprouting rate firstly increased and then decreased rapidly when maternal diameter of wild Prunus divaricata increased,and it reached maximum when the maternal diameter class isⅥ(20.0-23.0 cm). More than 85 percent of adventitious buds from root suckers mainly happened in the first and second soil layer in different habitat. There were significant difference in the distribution layer of root suckers regeneration,and the first soil layer (0-1 cm) had the highest proportion in all the four habitats. Along with sprouting seedlings aging,the mortality decreased gradually in all the four habitats,and the seedlings in the bottom of gully had the highest mortality. References | Related Articles | Metrics

Select

On the Physiological Characteristic of Drought Resistance of Native Dactylis glomerata in Xinjiang at Seeding Stage ZHAO Li, MU Shu-yong, ZHANG Xian-hua 2015, 32 (5):  953-957.  doi: 10.13866/j.azr.2015.05.18 Abstract ( 682 )   PDF (1194KB) ( 724 )   Drought stress affects plant growth and development,often causes serious crops production reduction,for the first place in all of the abiotic stress damage,is one of the major natural disasters leading to forage grass production,animal husbandry production economic loss. A mimic drought stress was designed for 3 Dactylis glomerata in Xinjiang,three drought resistance index of proline,soluble sugar and MDA were determined after drought induced for 4,8,and 12 days. The results indicate: with aggravation of drought stress,the proline and MDA were increasing,while the soluble sugar initial declined,then increased. Relevant analysis results showed the relationships were significantly positive between soluble sugar and MDA and the correlation coefficient is 0.664.Although there was correlation among Proline and soluble sugar and malondialdehyde,but no significant correlation,the correlation coefficient was 0.071 and 0.389,respectively. It is thus clear that in the drought stress environment,three physiological indexes have different accumulation process,proline accumulation first,after the proline accumulation to a certain extent,a large number of accumulations of soluble sugar and malondialdehyde are following. Through the comparison of three physiological indexes,the Dactylis glomerata in Zhaosu showed better drought resistance of three areas. Drought resistance of Dactylis glomerata is a complex physiological process,has close relations with its varieties,survival environment. How to better evaluate the drought resistance and its mechanism of Dactylis glomerata,it is necessary to conduct an in-depth research. References | Related Articles | Metrics

Climate and Climatic Change

Select

Inversion and Comparison of Arid Land Surface Temperature Based On HJ-1B Thermal Infrared Data PAN Yi-fan, ZHANG Xian-feng 2015, 32 (5):  958-965.  doi: 10.13866/j.azr.2015.05.19 Abstract ( 872 )   PDF (1945KB) ( 1065 )   Land surface temperature (LST) is of great significance to the hydrology,ecology,environment,biogeochemical and global climate change research. Remote sensing can provide 2D land surface temperature distribution information,and can be quickly synchronously to obtain a large area of land surface temperature. Thermal remote sensing can quickly access to the LST data over a large area. Due to less atmospheric water content,LST retrieval from remote sensing data in arid areas is relatively less impacted by atmospheric condition,which enables the single-channel algorithms achieve better inversion result. The HJ-1B satellite only acquires thermal data at a single channel,thus the comparison and assessment of the three mono-channel algorithms for LST retrieval are significant for either algorithm selection or usability test of the HJ-1B thermal data. In this study the radiative transfer equation algorithm,the mono-channel algorithm and the generalized single-channel algorithm were selected to retrieve the LST of the arid areas in Xinjiang based on the HJ-1B satellite thermal infrared images (IRS4). The results simulated by MODTRAN 4.0 show that three inversion algorithms can achieve high accuracy of LST estimation from the HJ-1B/IRS4 image data in the Shihezi and surrounding areas,with an average error of -0.75 to 0.51 K,RMSE of -0.17 to 0.13 K,respectively. Comparison between the LST derived from the HJ-1B data using the three algorithms and the MODIS LST product,indicates that the average error is -1.88-0.83 K,and the root-mean-square error is 3.8 K with a higher determination coefficient of greater than 0.8. References | Related Articles | Metrics

Select

Comparative Analysis on Atmospheric Circulation Anomalies of Heavy Drought Event in Northern China in 1986 and 1997 DUAN Hai-xia, LI Yao-hui, LIU Yun-yun 2015, 32 (5):  966-976.  doi: 10.13866/j.azr.2015.05.20 Abstract ( 719 )   PDF (4166KB) ( 738 )   In order to study the features and causes of the drought disasters,the two drought events and their atmospheric circulation anomaly occurred in the northern China in summer of 1986 and 1997 is examined using daily stations precipitation data,daily monsoon monitoring index,daily subtropical high index,74 atmospheric circulation indices and NCEP/NCAR reanalysis data. The results show that,in comparison with 1986,the drought in 1997 had a longer duration,stronger disaster degree and larger range. The two Western Pacific Subtropical High (WPSH) evolutions showed a significant difference. This results display that the WPSH position is stronger and larger,in comparison with 1986,in addition to a shift to the west and south. This results in less water vapor transport from the tropical Indian Ocean and the South China Sea,and the sinking motion anomaly. Furthermore,the analysis of Pacific sea surface temperature showed that distribution of different equatorial and northwest Pacific SSTs affected different oscillation of the North-South and East-West of WPSH,thereby affecting the different arid region distribution in the two drought process. References | Related Articles | Metrics

Select

Variation Characteristics of Aerosol Scattering Coefficient in Taklimakan Desert PENG Yan-mei, HE Qing, LIU Xin-chun, XIAO Gao-xiang, WEI Zi-jie 2015, 32 (5):  977-982.  doi: 10.13866/j.azr.2015.05.21 Abstract ( 712 )   PDF (1998KB) ( 930 )   The single-band integral nephelometer observation data of Taklimakan Desert Taklimakan Desert atmosphere Observation Station (referred to as:Tazhong Test Station) in 2010,combined with meteorological Tazhong observations,were used to analyze aerosol scattering coefficient variations and change in aerosol scattering coefficient under different weather conditions in Tazhong. Study showed that: ① Hour average of scattering coefficient in Tazhong was 318.4 Mm-1,and the values concentrated on 400 Mm-1 or less. Diurnal variation ranged from 276.4 to 387.0 Mm-1,and showed a single peak change. The values in daytime were bigger than that at night,and the maximum and minimum values appeared at 2:00 and 17:00,respectively. High values of the monthly average concentration appeared from March to August,especially March to April. The minimum values appeared in February. Seasonal variation of the scattering coefficient changed in the following way: spring> summer> autumn> winter.② When dust weather occurred,scattering coefficient increased significantly,and changed in different dust weather like this: the sandstorm> blowing sand> floating dust. The scattering coefficient when sandstorm was happening most concentrated from 2 000 to 2 500 Mm-1. When blowing sand was happening,the scattering coefficient ranged from 300 to 400 Mm-1. When floating dust was happening,the values were mainly under 300 Mm-1. ③ The scattering coefficient values in cloudy day was significantly greater than that in sunny day,the two values were 356.5 Mm-1 and 129.1 Mm-1,respectively. Both changes in two kinds of days were relatively stable overall,and obvious fluctuations appeared from 8:00 to 11:00 and 20:00 to 22:00. References | Related Articles | Metrics

Select

On the Aerosol Optical Properties at the Southwestern Margin of Taklimakan Desert YU Jie, CHEN Quan-liang, CHE Hui-zheng 2015, 32 (5):  983-990.  doi: 10.13866/j.azr.2015.05.22 Abstract ( 739 )   PDF (3181KB) ( 767 )   In this paper,aerosol optical depths (AODs) at four ngstrms of 440,675,870,1 020 nm and ngstrm exponent between 440 nm and 870 nm are retrieved based on the observations of CE318 sun photometer from May 2002 to March 2005 at Hetian station. After making cloud screening and data quality controlling of these retrieved optical parameters,the aerosol optical properties over the southwestern margin of Taklimakan Desert are analyzed. The results show as follows: the frequency distribution of AOD can be well fitted by a bi-mode normal distribution centered about 0.31 and 0.64 with the standard deviation of 0.007 and 0.11,respectively. The frequency distribution of ngstrm exponent can be well fitted (R2=0.99) by a bi-mode normal distribution centered about 0.12 and 0.33 with the standard deviation of 0.002 and 0.022,respectively. And more than half of the ngstrm exponent data are concentrated around the peak whose center is 0.12.There is obvious seasonal variation trend of aerosol optical properties at Hetian. The annual average AOD at 440 nm reaches about 0.61 with the standard deviation of 0.35. AODs are high in spring and summer but low in autumn and winter. ngstrm exponent are low in spring and summer but relatively high in autumn and winter. The maximum AOD occurs in May with a value of 0.81±0.48,and the minimum in November with a value of 0.31±0.12.The maximum and minimum ngstrm exponent occur in January with a value of 0.66±0.26 and May with a value of 0.06±0.06,respectively. The diurnal variation of AOD (ngstrm exponent) shows the characteristic of high (low) values in the morning and evening,and is relatively constant during the daytime. The annual averaged AOD and ngstrm exponent are relatively stable with the values around 0.57-0.60 and 0.22-0.23,respectively; however,there is no significant annual variability during 2002-2004. The relationship between AOD and ngstrm exponent shows obvious pattern of decreasing ngstrm exponent with increasing AOD, which indicates the dust aerosol of larger particle size are the major contributions to the high AOD. Compared with the existing study results,one can see that the aerosol optical properties at Hetian show the typical desert aerosol characteristics,while anthropogenic aerosols have little effect on the aerosol optical properties of this region. References | Related Articles | Metrics

Select

Variation of Humidity Index in Shihezi Region,Xinjiang from 1964 to 2012 WU Yan-feng, Bater Bake, LI Wei, WEI Xiao-qin, Jiayinaguli Wozatihan, Rasulov H H 2015, 32 (5):  991-999.  doi: 10.13866/j.azr.2015.05.23 Abstract ( 617 )   PDF (3984KB) ( 754 )   Shihezi is located in Xinjiang,an arid area of Northwestern China. In the context of global warming,the dry-wet conditions of Shihezi have significantly influence on many aspects of production and life. Therefore,it is necessary to conduct the research to investigate the variation of past decades and predict change trend of dry-wet conditions in the future,so as to provide reference to relative research and farming operation management. Based on the daily temperature and precipitation data in Shihezi region from 1964 to 2012,the method of trend analysis,M-K analysis,wavelet analysis,relative humid index,and R/S analysis was applied to analyze the temporal characteristics in this area. The results showed that the annual temperature and precipitation had a significantly increasing trend. The relative humid of Shihezi region,summer and four stations increased while the relative humid of spring and autumn decreased in the past 49 years. Abrupt change occurred in the changing process of the relative humid index of annual change,spring,summer,autumn,Shihezi city,Mosuowan County and Paotai county while not occurred in Wulanwusu County. The relative humid index,annual and summer change in Shihezi region and in four stations,would transform form increasing trend to decreasing trend while transform form decreasing trend to increasing trend in spring and autumn. This paper can provide reference for the research of dry-wet conditions variation and response to meteorological drought efficiently. References | Related Articles | Metrics

Select

Evaluation and Cause Study on the Snow Disasters in Pastoral Areas of Northern Xinjiang ZHUANG Xiao-cui, ZHOU Hong-kui, WANG Lei, LI Bo-yuan 2015, 32 (5):  1000-1006.  doi: 10.13866/j.azr.2015.05.24 Abstract ( 702 )   PDF (1137KB) ( 870 )   Past research has shown it is difficult to objectively assess the snow disaster of the actual situation on the basis of nature factor purely as to determine the snow disaster severity. We used the maximum snow depth,precipitation month by month,the temperature every day from 7 meteorological stations in Altay from 1961 to 2012,and precipitation from April to September,accumulated temperature greater than zero,the actual data of snow disaster situation over the same period,sunspot and herbage data from 2007 to 2012,studied the index and the causes of snow disaster in this area. The result showed that the comprehensive index of snow disaster has high accuracy for evaluating the snow disaster and the snow disaster could be divided into 4 classes: The most snow disaster years,secondary heavy snow disaster years,moderate snow disaster years and light snow disaster years. The most snow disaster years and secondary heavy snow disaster years mainly occurred in the early twenty-first Century,and the strength was more and more strong; The cause of the most snow disaster is the high frequency of heavy snowfall,and the strength is more and more strong ; that of the most snow disaster years were mainly caused by the much more heavy snowfall frequency,the large amount of snow,stronger strength,long duration,but the cause of secondary heavy snow disaster years was more complex; sunspot activated low value years,Scandinavia positive phase circulation pattern,and the AO index was very weak,secondary heavy snow disaster occurred easily in Altay. References | Related Articles | Metrics

Others

Select

Meteorological Effects on the Sand Transport of Mingsha Mountain and Crescent Moon Spring Scenic Area in Dunhuang ZHOU Huan, TIAN He, QU Jian-jun, NIU Qing-he, ZHANG Yi 2015, 32 (5):  1007-1016.  doi: 10.13866/j.azr.2015.05.25 Abstract ( 1157 )   PDF (2158KB) ( 826 )   Using the data recorded by the automatically meteorological stations around the Crescent Moon Spring, combined with the result of simulating the mountain and valley breezes by WRF-LES model to analyze the wind field and sand transport in this area. The results show that: ① There are three main wind streams in Dunhuang every year. They are northwest wind, northeast wind and south wind. The influence of these three kinds of wind balance out each other, keeping the sand dunes in this area stable;② The sand movement is stronger in spring and summer and more intense in the peripheral region of Crescent Moon Spring. When the winds pass through the Spring, the acting time of sand driving wind will reduce percent 30 to percent 40.The terrain changes the direction of sand driving wind and in the same time the wind energy disperses, the velocity of the wind slows down and the sands in the wind will be left in the valley;③ The simulation results prove that: With only influence of the solar radiation, the wind direction will reverse between day and night in the research field. It’s a phenomenon of down-valley wind. The specific heat capacities of water and sand are different, which makes the temperature of lake and dunes different from each other either in day and night. It forces high pressure and low pressure to appear in the boundary layer. The high pressure and low pressure cause the down-valley wind finally. Between the down-valley wind and mountain wind, the mount wind has larger contribution to the sand transportation. Average velocity of the mountain wind is 0.767 m·s-1, from the lake to both north and south. With the influence of this kind of mountain wind, the total sand discharge from the lake to outside increase percent 8.48. References | Related Articles | Metrics

Select

Blown Sand Hazard Situation and Spatial Difference of Mechanical Sand Prevention System along Alar-Hetian Desert Highway WANG Shi-jie, XU Xin-wen, KANG Xiang-guang, ZHANG Heng, TIAN Ye, LIU Jian-yu, MAO Wen-lian, TANG Jin-feng, ZENG Hui, ZENG Cheng 2015, 32 (5):  1017-1023.  doi: 10.13866/j.azr.2015.05.26 Abstract ( 681 )   PDF (2146KB) ( 797 )   In order to provide specific maintenance for the mechanical sand prevention system along the Alar-Hetian Desert Highway,the research group made a detailed survey and researched about its present and wind-sand environment. The situation and spatial difference of blown sand hazard of the mechanical sand prevention system along the Alar-Hetian Desert Highway using the GIS spatial analysis function. The study results show that: ① the heavier and heavy disaster sections of the straw checkerboard mainly distribute K400-K417,K505-K578,K600-K610 a total length about 100 km,only account for percent 24.8 of overall length; the serious damage of the fence along the highway mainly concentrated in the middle and partial southern of the road,a total length about 199 km,accounting for percent 49.3 of overall length. ② In K227-K311 sections,the damage extent on the east side of the sand protection system is heavier than the west side. The sections in which the extent of damage on the west side is heavier than the east side are mainly distributed in the 80 km range of the Hongbaishan.③ The damage extent in 5 geomorphic types is 0.67,0.75,0.79,0.80 and 0.70,respectively. In area Ⅰ the damage is lesser,Ⅱ and Ⅴ medium,Ⅲ and Ⅳ heavier. The lighter damage sections of the sand protection system are mainly distributed in the north and south tip and the heavy sections mainly focus on K382-K582 sections in the middle of the road. References | Related Articles | Metrics

Select

Ecological Security Assessment and Countermeasures of Hunshandake Desertification Control Regions CHI Yan-yan, XU Kai-peng, ZHANG Hui-yuan 2015, 32 (5):  1024-1031.  doi: 10.13866/j.azr.2015.05.27 Abstract ( 638 )   PDF (1486KB) ( 769 )   Ecological security research is a hotspot of research on the current large-scale ecology problems. Hunshandake region is one of top ten sand in China,mainly composed of fixed and semi-fixed dunes of sand landscape; its edge area has become one of the important dust activity sources of Beijing-Tianjin region in recent years. Regional ecological security pattern is significant for regional sustainable development. As an important area of maintenance sand-fixing functions,the ecological security of Hunshandake desertification control regions is particularly important. This research tried to establish index system of ecological security evaluation based on vegetation growth,land cover pattern and soil erosion of Hunshandake,through analyzing the influence factors of desertification process. Three indicators evaluation results were identified and integrated into an overall ecological security assessment by using remote sensing and GIS technology. Results showed,relatively unsafe areas accounts for 35.42% of the regional lands,unsafe areas and very unsafe areas accounts for 3.42% and 0.05% of the regional lands respectively. From 2000 to 2008,natural landscapes changed to deserts in parts of center areas,account for 6.84% of the regional lands. In addition,natural landscapes changed to crop land in parts of southern and eastern areas,account for 1.19% of the regional lands. With the further research of ecological security evaluation index,evaluation method and complete data,there will be more accurate evaluation results. On the basis of ecological security assessment of Hunshandake desertification control regions,combination with analysis of economic and social development stress,regional ecological security countermeasures were put forward. References | Related Articles | Metrics

Select

Hydrogeochemistry and Isotope Features in the Middle and Upper Reaches of Buha River Basin PENG Hong-ming, XU Wei-lin, HE Qing, YUAN You-jin, WANG Wan-ping, WANG Sheng-bin 2015, 32 (5):  1032-1038.  doi: 10.13866/j.azr.2015.05.28 Abstract ( 1204 )   PDF (2152KB) ( 1015 )   In recent 20 years,with the rapid development of key town economy in the river basin,affected by human activities and global climate change,the basin water cycle factors changed. It is necessary to carry out the research on groundwater circulation and water quality evolution rule. Buha river water,the main source of Qinghai Lake,a main place for breeding Gymnocypris przewalskii of Qinghai Lake,is significant to the stability of water resources and quality according to the surface water circulation and water chemistry. We investigated the regional hydrogeology background to outline the relationships of river water and groundwater as well as using water geochemistry and isotopes. The results suggested that the origin of river water came from precipitation and snow melt water in the river source area with elevation of 4 600 m,river water recharged groundwater in the river valley area,and main flow path of groundwater was from the basement rock mountainous area to piedmont alluvial plain. With respect to groundwater circulation,the first and second terrace was recharged by river water leakage,and the third terrace was recharged by river water leakage and lateral runoff from piedmont alluvial plain. The study result reveals the different types of groundwater recharge source and circulation change rule,and provides a scientific reference for studying the groundwater environmental evolution of the river basin and the influence of human activities on the groundwater environment in further. References | Related Articles | Metrics

Select

On the Net Ecosystem Productivity in the Upper Reaches Area of Shiyang River XU Chun-hua, ZHANG Hua, MA Rui-fen 2015, 32 (5):  1039-1045.  doi: 10.13866/j.azr.2015.05.29 Abstract ( 734 )   PDF (3098KB) ( 629 )   By using MODIS data,combining with CASA (Carnegie Ames Stanford that CASA) model and soil respiration fitting equation,this paper simulated the Net Ecosystem Productivity (NEP) of different vegetation types in the upper reaches area of Shiyang River in 2012. The result shows that: ① The NEP is 126.96 g·m-2·a-1 and the total annual NEP is 1.38 × 1010 t·a-1 from 2003 to 2012,and it has been a marked increase in recent 10 years. ② The NEP shows a spatial pattern,becoming lower in turns from the central to the north and south. Overall,it acts as a carbon sink,only a small part of the desert acts as a carbon source. There are larger differences between different ecosystems to the NEP. This is correlated to hydrothermal conditions and the different distribution of vegetation types in the study area. ③ Interannual variation of the NEP was positively related to the temperature and precipitation,the precipitation has a larger influence on NEP,and complementary in the space. References | Related Articles | Metrics