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Distribution assessment of soil erosion with revised RUSLE model in Tianshan Mountains

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Journal of Mountain Science 2024年第3期21卷 850-866页

作者： wei wenyu liu Ya ZHANG Lixia LI Lanhai State Key Laboratory of Desert and Oasis ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of chinese academy of sciences Beijing 100049China Reaserch Center of Educational in xinjiang Xinjiang Normal UniversityUrumqi 830017China

aSoil degradation caused by soil erosion is one of the world's most critical environmental *** erosion in the Tianshan Mountains has caused various environmental problems in the surrounding *** study used remote sensing data to analyze the distribution of the factors influencing soil erosion,and the revised universal soil loss equation(RUSLE)to calculate the total amount and distribution characteristics of soil erosion in the Tianshan Mountains in *** to the large error of RUSLE in soil erosion estimation in mountainous areas,this study modified RUSLE equation based on the characteristics of snow cover in the Tianshan *** results show that the average soil erosion was 1690.3 t/(km^(2)·year),of which insignificant erosion,slight erosion and moderate erosion accounted for 42,8%,22.4%and 9.9%,*** erosion and above accounted for 13.3%.The accuracy of the soil erosion modulus calculated by the RUSLE was only 61.9%,with an average error of 1631.9 t/(km^(2)·year).The average error of the double-coefficient correction method was 1259.1 t/(km^(2)·year),and the average error of the modified formula method was reduced by 40.3%compared with the RUSLE,reaching 973.7 t/(km^(2)·year),and its accuracy reached 76.2%.Very severe erosion and catastrophic erosion are distributed on mountain ridges with higher elevation and on the northern area with higher *** cover has a certain inhibitory effect on soil erosion,and snow cover in alpine mountains is a factor that cannot be ignored in soil erosion research.

关键词： RUSLE Snow cover Erosion categories High-elevation area

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

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

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

This article discussed about snow temperature variations and their impact on snow cover *** temperature recorders were used to sample at 10-minute intervals at the Tianshan Station for Snow-cover and Avalanche Research,chinese academy of sciences.10-layer snow temperature and the snow cover parameters were measured by the snow property analyzer (Snow Fork) in its Stable period,Interim period and Snow melting *** indicate that the amplitude of the diurnal fluctuation in the temperature during Snow melting period is 1.62 times greater than that during Stable *** up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours,and lags behind the peak atmospheric temperature by more than 0.2 hours during all three *** optimal fitted function of snow temperature profile becomes more complicated from Stable period to Snow melting period.22 h temperature profiles in Stable period are the optimal fitted by cubic polynomial *** Interim period and Snow melting period,temperature profiles are optimal fitted by exponential equation between sunset and sunrise,and by Fourier function when solar radiation is *** vertical gradient in the snow temperature reaches its maximum value at the snow surface for three *** peak of this maximum value occurs during Stable period,and is 4.46 times greater than during Interim *** absolute value of temperature gradient is lower than 0.1°C cm-1 for 30 cm beneath snow *** temperature and temperature gradient in Stable period～Interim period indirectly cause increase (decrease) of snow density mainly by increasing (decreasing) *** it dramatically increases its water content to change its permittivity and snow density in Snow melting period.

关键词：温度变化天山西部物理参数雪盖中国最佳拟合函数积雪密度峰值温度

Change in Fresh Snow Density in Tianshan Mountains,china

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chinese Geographical Science 2011年第1期21卷 36-47页

作者： CHEN Xia wei wenshou liu mingzhe xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of chinese academy of sciences Beijing 100049 China institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Tianshan Station for Snow-cover and Avalanche Research Chinese Academy of Sciences Urumqi 830011 China

The fresh snow density was observed with snow analyzer (Snow Fork) at Tianshan Station for Snowcover and Avalanche Research, chinese academy of sciences from February 21 to March 5, 2009. Results show that fresh snow density increases from the 5th h to the 291st h after the snowfall, with an average rate of increase of 4.0×10-4 g/(cm3·h) (R2 = 0.943). Analysis shows that fresh snow density is negatively correlated with the compac-tion rate of fresh snow (R2 = -0.960). Inversely, it is positively correlated with fresh snow viscosity (R2 = 0.896). In relation to meteorological factors, ground temperature rising at a depth of 40 cm is the major driving factor of snow density increase. The temperature increase in fresh snow layer and the decrease in depth hoar layer have the most prominent impacts on the snow density increase in the afternoon. Principal component analysis shows that the de-terminant factors of fresh snow density change can be grouped into 3 types as follows: 1) dynamic factor contributes about 69.71% to fresh snow density change, with a significant effect from the 5th h to the 106th h after the snowfall; 2) exogenous energy factor contributes about 20.91% to it, with a significant effect at the 130th h; and c) endoge-nous energy factor contributes about 9.38% to it, with a significant effect at the 130th h and the 195th h.

关键词：密度变化中国科学院天山山脉地表温度主成分分析气象因素驱动因素动态因素

Aerosol optical absorption by dust and black carbon in Taklimakan Desert,during no-dust and dust-storm conditions

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Particuology 2012年第4期10卷 509-516页

作者： Hui Lu wenshou wei mingzhe liu weidong Gao Xi Han xinjiang institute of ecology and geography Chinese Academy of SciencesUrumqi 830011China Graduate School of the chinese academy of sciences Beijing 100049China urumqi institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China School of Resources and Environment University ofJinanJinan 250000China

Aerosol absorption coefficient σap involves the additive contribution of both black carbon aerosol （BC） and dust aerosol. The linear statistical regression analysis approach introduced by Fialho et al. （2005） is used to estimate the absorption exponents of BC and dust aerosol absorption coefficients, and further to separate the contributions of these two types of aerosols from the total light absorption coefficient measured in the hinterland of Taklimakan Desert in the spring of 2006. Absorption coefficients are measured by means of a 7-wavelength Aethalometer from 1 March to 31 May and from 1 November to 28 December, 2006. The absorption exponent of BC absorption coefficient α is estimated as （-0.95 ± 0.002） under background weather （supposing the observed absorption coefficient is due only to BC）; the estimated absorption exponent of dust aerosol absorption coefficient/5 during the 6 dust storm periods （strong dust storm） is （-2.55 ± 0.009）. Decoupling analysis of the measured light absorption coefficients demonstrates that, on average, the light absorptions caused by dust aerosol and BC make up about 50.5% and 49.5% respectively of the total light absorption at 520 nm; during dust weather process periods （dust storm, floating dust, blowing dust）, the contribution of dust aerosol to absorption extinction is 60.6% on average; in the hin- terland of desert in spring, dust aerosol is also the major contributor to the total aerosol light absorption, more than that of black carbon aerosol.

关键词： Black carbonDustAbsorption coefficientAbsorption exponent of absorptioncoefficientDecoupling of absorption coefficient

Allopatric divergence and regional range expansion of Juniperus sabina in china

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Journal of Systematics and Evolution 2010年第3期48卷 153-160页

作者： 1Yu-Peng GUO 1Ru ZHANG 1Cui-Yun CHEN 2Dang-wei ZHOU 1Jian-Quan liu 1(Division of Molecular ecology,Key Laboratory of Arid and Grassland ecology,School of Life sciences,Lanzhou University,Lanzhou 730000,china) 2(Key Laboratory of Adaptation and Evolution of Plateau Biota,Northwest institute of Plateau Biology,chinese academy of sciences,Xining 810000,china) (Division of Molecular ecology Key Laboratory of Arid and Grassland Ecology School of Life Sciences Lanzhou University Lanzhou 730000 China) (Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810000 China)

In this study,we aimed to study the phylogeographic pattern of Juniperus sabina,a shrub species commonly occurring in the northern,northwestern and western china. We sequenced three chloroplast DNA fragments (trnL-trnF,trnS-trnG,and trnD-trnT) for 137 individuals from 16 populations of this species. Five chloroplast DNA chlorotypes (A,B,C,D,and E) were identified and they showed no overlapping distribution. The population subdivision is very high (GST=0.926,NST=0.980),suggesting a distinct phylogeographic structure (NST>GST,Pxinjiang,western xinjiang,and northern-northwestern china. However,within each region,the interpopulation differentiation is extremely low. These results as well as statistical tests suggested distinct allopatric differentiations between regional populations and independent glacial refugia for postglacial recolonization. The deserts that developed during the late Quaternary might have acted as effective barriers to promote genetic differentiation among these regions. However,the low diversity dominated by the single chlorotype within each fragmented region suggested that all current populations were derived from a common regional range expansion.

关键词： cpDNA genetic diversity Juniperus sabina phylogeography range expansion.

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艾比湖流域降水与径流变化特征分析

水土保持学报 2011年第5期25卷 21-25页

作者：刘世薇周华荣梁雪琼李玉霞巴乌龙中国科学院新疆生态与地理研究所乌鲁木齐830011 中国科学院东北地理与农业生态研究所长春130012 中国科学院研究生院北京100049

以艾比湖流域的博尔塔拉河(博河)和精河为例,基于1961-2008年的水文气象数据,运用Mann-Kendall非参数检验、线性倾向估计、小波分析等方法,分析流域内2条河流的变化趋势及周期特征,得到以下结论:(1)48年来,艾比湖流域博乐站和精河站降... 详细信息

以艾比湖流域的博尔塔拉河(博河)和精河为例,基于1961-2008年的水文气象数据,运用Mann-Kendall非参数检验、线性倾向估计、小波分析等方法,分析流域内2条河流的变化趋势及周期特征,得到以下结论:(1)48年来,艾比湖流域博乐站和精河站降水量均呈现增加的趋势,其中,博乐站的线性倾向斜率为8.54mm/10年;精河站的线性倾向斜率为12.74mm/10年。(2)博河和精河年径流量均呈现极显著的增加趋势,其Z值分别为2.42和2.45,两者均通过а=0.05显著性检验。(3)艾比湖流域年降水量序列的小波系数等值线分布比较密集,存在明显的小波系数高低值中心震荡。两站年降水量在48年的时间序列中存在多个周期。(4)流域内2条河流均有明显的周期性变化,尤其以年代际周期最为显著。在每个周期中径流量又经历了几次"丰枯"交替。(5)博河和精河2条河流径流量与降水量的相关系数分别为0.564和0.490,均通过a=0.01的R显著性检验,表明降水是流域径流量的重要补给源之一。

关键词：径流降水变化趋势艾比湖流域

Application of wind profiler data to rainfall analyses in Tazhong Oilfield region,xinjiang,china

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Journal of Arid Land 2012年第4期4卷 369-377页

作者： MinZhong WANG wenshou wei Qing HE XinChun liu ZhongJie ZHAO urumqi institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Taklimakan Desert Atmospheric Environment Observation Experimental Station Tazhong 841000 China Meteorological Office of Bayinguoleng Mongolian prefecture Kurler 841000 China

To improve the level of meteorological service for the Oilfield region in the Taklimakan Desert, the urumqi institute of Desert Meteorology of the china Meteorological Administration （CMA） conducted a detection experiment by means of wind profiling radar （WPR） in Tazhong Oilfield region of xinjiang, china in July 2010. By using the wind profiler data obtained during the rainfall process on 27 July, this paper analyzed the wind field fea- tures and some related scientific issues of this weather event. The results indicated that：（1） wind profiler data had high temporal resolution and vertical spatial resolution, and could be used to analyze detailed vertical structures of rainfall processes and the characteristics of meso-scale systems. Before and after the rain event on 27 July, the wind field showed multi-layer vertical structures, having an obvious meso-scale wind shear line and three airflows from different directions, speeding up the motion of updraft convergence in the lower atmosphere. Besides, the wind directions before and after the rainfall changed inversely with increasing height. Before the rain, the winds blew clockwise, but after the onset of the rain, the wind directions became counterclockwise mainly; （2） the temperature advection derived from wind profiler data can reproduce the characteristics of low-level thermodynamic evolution in the process of rainfall, which is capable to reflect the variation trend of hydrostatic stability in the atmosphere. In the early stage of the precipitation on 27 July, the lower atmosphere was mainly affected by warm advection which had accumulated unstable energy for the rainfall event and was beneficial for the occurrence of updraft motion and precipitation; （3） the ＂large-value zone＂ of the radar reflectivity factor Z was virtually consistent with the onset and end of the rainfall, the height for the formation of rain cloud particles, and precipitation intensity. The reflectivity factor Z during this event varied app

关键词： wind profiling radar vertical atmospheric structure temperature advection radar reflectivity factor Z Tazhong Oiifield Taklimakan Desert

Energy Budget over Seasonal Snow Surface at an Open Site and Beneath Forest Canopy Openness during the Snowmelt Period in Western Tianshan Mountains,china

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Journal of Mountain Science 2015年第2期12卷 298-312页

作者： LU Heng wei Wen-shou liu mingzhe HAN Xi HONG Wen xinjiang institute of ecology and geography Chinese Academy of Sciences University of chinese academy of sciences institute of Desert Meteorology China Meteorological Administration Tianshan Station for Snow & Avalanche Research

In this study, meteorological factors and snowmelt rate at an open site on sunny slope(OPS) and beneath forest canopy openness on shady slope(BFC) were measured using an automatic weather station and snow lysimeter during the snowmelt period in 2009, 2010 and 2013. The energy budget over snow surface was calculated according to these meteorological datasets. The analysis results indicated that the net shortwave radiation(K) and sensible heat flux(H) were energy sources, and the latent heat flux(LVE) was energy sinks of snow surfaces at all sites. The net longwave radiation(L) was energy sink at OPS and 80% BFC, but energy source at 20% BFC. The gain of K, H, and the loss of LVE at BFC were obviously lower than those at OPS. The L was the maximum difference of energy budget between snow surface at BFC and OPS. In warm and wet years, the most important factor of the energy budget variation at OPS was air humidity and the second mostimportant factor was air temperature. However, the ground surface temperature on the sunny slope was the most important factor for L and energy budget at BFC. With the increases in forest canopy openness and the slope of adjacent terrains, the influences of ground surface temperature on the sunny slope on L and the energy budget over snow surface at BFC increased, especially when the snow cover on the sunny slope melts completely.

关键词：能量收支森林冠层天山西部融雪中国森林网站季节性表面温度

Analyses of temperature and humidity profiles and heat balance of the surface boundary-layer in the hinterland of the Taklimakan Desert

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chinese Science Bulletin 2008年第S2期53卷 22-30页

作者： wei wenshou WANG MinZhong HE Qing LEI JiaQiang ALI Mamtimin institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China xinjiang institute of ecology and geography Chinese Academy of SciencesUrumqi 830011China

The daily variation regularities of micro-meteorological features, such as the surface layer temperature and humidity profiles of the inner desert in summer, the temperature of sand bed, the radiation of the earth's surface and the heat balance, were analyzed by combination method and logarithm regression according to the data obtained from the Atmospheric Environmental Observation Station of Taklimakan Desert in July―August of 2006 and 2007. It has been shown that temperature inversion occurred near the surface layer at night in summer, the temperature increased with the height within a certain altitude range, and the reverse was true during the daytime. The ground surface radiation balance of the Taklimakan Desert was mainly positive; other radiation components (the global radiation, the reflective radiation, the ground upward long wave radiation and the net radiation) exhibited daily variation char- acteristics evidently and showed normal diurnal cycle, except for the downward atmospheric long-wave radiation. The heat exchange of the surface layer of the desert was dominated by turbulence sensible heat, and only a small portion of heat was transferred to the atmospheric surface layer in the form of latent heat. The surface sensible heat and latent heat changed with the increase and decrease of sun elevation angle, with maximum of the latent heat appearing in wee hours and the peak value of the sensible heat appearing at noon. Observation and analysis showed that heating effect of the underlying surface of the desert was great on the aerosphere; the surface was a high heat source during the day and became a weak cold source at night.

关键词： Taklimakan Desert temperature profile humidity profile radiation balance heat balance