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Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China
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作者 SONG Dacheng ZHAO Wenzhi +5 位作者 LI Guangyu WEI Lemin WANG Lide YANG Jingyi WU Hao MA Quanlin 《Journal of Arid Land》 SCIE CSCD 2024年第5期668-684,共17页
The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand b... The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 a.However,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian activities.This study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain size.In March 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand barriers.Surface sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were analyzed.Results indicated a predominance of fine and medium sands in the surface sediments of the study area.The deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,respectively.This trend became markedly pronounced a decade after the deployment of clay–sand barriers.The effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment particles.Coarser particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the barriers.By contrast,the contents of finest particles such as silt and clay were higher in the downwind(southeast)region of the sampling plots.For the study area,the deployment of clay–sand barriers remains one of the most cost-effective engineering solutions for aeolian erosion control,with sediment grain size parameters serving as quantitative indicators for the assessment of these barriers in combating desertification.The results of this study provide a theoretical foundation for the construction of windbreak and sand fixation systems and the optimization of artificial sand control projects in arid desert areas. 展开更多
关键词 clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area
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Distribution Characteristics of Soil Total Nitrogen in Low-efficiency Forest Land in the Northern Windy Desert Area of Jingbian County
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作者 Tingting MENG Yingying SUN +1 位作者 Yan LI Yuhu LUO 《Asian Agricultural Research》 2023年第3期26-29,共4页
[Objectives]The paper was to investigate the distribution characteristics of soil total nitrogen in low-efficiency forest land in the northern windy desert area of Jingbian County.[Methods]The distribution of soil tot... [Objectives]The paper was to investigate the distribution characteristics of soil total nitrogen in low-efficiency forest land in the northern windy desert area of Jingbian County.[Methods]The distribution of soil total nitrogen in the 0-40 cm soil layer of 5 towns in the northern windy desert area of Jingbian County was studied through field sampling and laboratory detection.[Results]The average soil total nitrogen contents of Hongdunjie Town,Haizetan Town,Huanghaojie Town,Ningtiaoliang Town,Dongkeng Town and windy desert area in the 0-20 cm soil layer were 0.259,0.224,0.242,0.248,0.431 and 0.275 g/kg,respectively.The soil total nitrogen content in Dongkeng Town was higher than those in other towns,while there was little difference among other regions.The average total nitrogen contents in the 20-40 cm soil layer were 0.239,0.285,0.113,0.262,0.349 and 0.241 g/kg,respectively.The soil total nitrogen content in Huanghaojie Town was slightly lower than those in other towns,while that in Dongkeng town was higher.The variation coefficient of soil total nitrogen content in the survey area was greater than 30%,and there was great difference in spatial distribution.With the increase of soil depth,there was little change in soil total nitrogen content,namely the soil total nitrogen contents in 5 towns and windy desert area were not statistically different in the 0-40 cm soil layer.According to the nutrient grading standard of the second national soil survey,the soil total nitrogen content in the survey area was in the deficiency grade.[Conclusions]The research will provide a scientific guidance for the healthy and sustainable development of vegetation in arid regions. 展开更多
关键词 Windy desert area Low-efficiency forest land Soil total nitrogen
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Probabilistic modeling of soil moisture dynamics in a revegetated desert area 被引量:2
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作者 Lei Huang ZhiShan Zhang YongLe Chen 《Research in Cold and Arid Regions》 CSCD 2013年第2期205-210,共6页
Soil moisture is the key link between land hydrological and ecological processes which plays an important role in the terrestrial water cycle. As extreme weather events have increased in recent years, the stochastic s... Soil moisture is the key link between land hydrological and ecological processes which plays an important role in the terrestrial water cycle. As extreme weather events have increased in recent years, the stochastic simulation of soil moisture has gradually become the focus of ecohydrology research. Based on continuous monitoring of soil moisture data from 2008 to 2011, and histor- ical precipitation data from 199l to 2011, combined with the Rodriguez-Iturbe soil moisture dynamic stochastic model, soil mois- ture dynamics and its probability density fimction in a revegetated desert area was simulated. Results show that annual soil mois- ture dynamic changes of the revegetated desert area during the growing season complied with rainfall distribution; soil moisture probability presents a single-peak distribution in the plant rhizosphere layer (0-60 cm). The peak width in the 20 cm topsoil was wider than in other soils, and the distribution presented the strong fluctuations and multiple aggregates. The peak widths of 40 cm and 60 cm soil moisture probability distribution were small, which are in accordance with simulated results of the Rodri- guez-lturbe model. This confrms that the Rodriguez-Imrbe model has good applicability and can well simulate the statistical characteristics of soil moisture in an arid revegetated desert area. 展开更多
关键词 revegetated desert area soil moisture Rodriguez-Iturbe model probability density functions
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Environmental Conditions of Barchan Dune and Barchan Chain-A Case Study from the Hexi Desert Area of Gansu 被引量:2
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作者 Chang Zhaofeng Wang Qiangqiang +5 位作者 Zhang Jianhui Xi Junqiang Wang Qi Zhang Dekui Tang Jinnian Zhang Huiwen 《Animal Husbandry and Feed Science》 CAS 2015年第6期383-388,共6页
[Objective] The paper was to discuss why the top of tall barchan dunes and barchan chains widespread in single prevailing wind area had not been leveled by wind erosion. [Method] Based on the preliminary survey of dis... [Objective] The paper was to discuss why the top of tall barchan dunes and barchan chains widespread in single prevailing wind area had not been leveled by wind erosion. [Method] Based on the preliminary survey of distribution status,the morphological characteristics and environmental conditions of barchan dunes and barchan chains in Hexi desert area of Gansu were investigated in details. The significance of difference between samples and significance of correlation between indicators were examined via variance test. [Result] Barchan dunes and barchan chains in Hexi desert area of Gansu distributed at the leeward direction of desert fringe,generally in patch distribution. The distribution area was gravelly beach or cohesive gravel beach,with broader dune slack; winds in distribution area of barchan dunes and barchan chains blew obviously from one direction,while winds at other directions were light or occasionally strong but with low frequency;the barchan dune in the desert fringe of Hexi desert area of Gansu was relatively tall,while barchan chain was even more taller and larger. Coincidence or separation of the dune peak and the sand ridge might be related to distribution frequency of dominant prevailing wind or wind at opposite direction and the observation seasons.[Conclusion]Studying top stability of barchan dune has an important academic value in revealing blowing sand movement rule at desert fringe,invasion of sand flow,and expansion of desert. 展开更多
关键词 Barchan dune Morphological characteristics Regional environment Wind speed and direction Hexi desert area of Gansu
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Comparisons between Movement Speed of Main Types of Dunes:A Case Study of Desert Areas in Hexi Region of Gansu Province 被引量:2
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作者 CHANG Zhaofeng ZHU Shujuan +5 位作者 SHI Xuegang ZHANG Jinhu LI Ya WANG Qi ZHANG Dekui DUAN Xiaofeng 《Journal of Landscape Research》 2016年第6期36-40,共5页
In desert areas in Hexi region,11 barchan dunes,6 chains of barchan dunes,6 pyramid dunes,6 parabolic dunes and 6 accumulated sand-belts were chosen to study their movement speed based on images obtained by Google Ear... In desert areas in Hexi region,11 barchan dunes,6 chains of barchan dunes,6 pyramid dunes,6 parabolic dunes and 6 accumulated sand-belts were chosen to study their movement speed based on images obtained by Google Earth in various periods.The results show that among the dunes,the movement of the barchan dunes was the fastest,followed by the chains of barchan dunes,and only the tops of the pyramid dunes swayed,while the parabolic dunes and accumulated sand-belts hardly moved forward.The higher the barchan dunes(or the chains of barchan dunes) were,the slower the movement was.On the contrary,the higher the pyramid dunes were,the faster the swing was.There was a positive correlation between the movement speed of the barchan dunes and the average wind speed of sandstorms. 展开更多
关键词 Barchan dunes Chains of barchan dunes Pyramid dunes Movement speed desert areas in Hexi region
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Effects of vibration in desert area caused by moving trains 被引量:1
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作者 Jabbar-Ali ZAKERI Morteza ESMAEILI +1 位作者 Seyedali MOSAYEBI Rauf ABBASI 《Journal of Modern Transportation》 2012年第1期16-23,共8页
The ballast layer, filled with fine particles like blown sand, is one of the important problems of ballasted railway tracks in desert areas. Blown sand, as a contaminator of ballast layer, increases track stiffness an... The ballast layer, filled with fine particles like blown sand, is one of the important problems of ballasted railway tracks in desert areas. Blown sand, as a contaminator of ballast layer, increases track stiffness and may cause serious damage to sleepers, pads, rails, and vehicles. In this paper, the effects of increasing track stiffness due to windy sands in the ballast layer and the train induced vibrations due to this phenomenon were studied. Based on field studies in a desert area in Iran, a two-dimensional finite/infinite element model for a railway track with plane strain condition was analyzed using the software ABAQUS, and the track vibrations were examined by changing the values of stiffness of ballast layer. Vibrations caused by the load of train at different distances from the cross-section of track were inves- tigated, and the values of vertical vibration displacement, velocity, and acceleration were calculated. Results show that acceleration values of vertical vibration increase with the increasing of ballast layer stiffness caused by the filling of sand, while the vertical vibration velocity of track and the induced ground displacement decrease. The farther the distance from the source of vibration, the less the displacement, velocity, and acceleration. In addition, the methods for reducing train-induced vibrations were introduced. 展开更多
关键词 train induced vibration desert area blown sand ballast layer stiffness
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A Study of Siliceous Pneumoconiosis in a Desert Area of Sunan County,Gansu Province,China 被引量:1
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作者 XU XIU-ZHEN’, CAT XI-GUANG, MEN XIAN-SEN, YANG PENG-YUN, YANG JING-FU, JING SONG-LIN HE JI-HUA, AND SI WEI-YIPeople’s Hospital of Gansu Province Sunan County Hospital of Gansu Province, Lanzhou730000, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1993年第3期217-222,共6页
Three hundred and ninety five residents in a desert area were examined with chest radiographs and 28 cases with siliceous pneumoconiosis were found. The prevalence of siliceous pneumoconiosis was 7.09%, and that over ... Three hundred and ninety five residents in a desert area were examined with chest radiographs and 28 cases with siliceous pneumoconiosis were found. The prevalence of siliceous pneumoconiosis was 7.09%, and that over 40 years of age was 21%. The histological findings of lungs from a camel living in that area for 20 years also confirmed to have siliceous pneumoconiosis. 展开更多
关键词 A Study of Siliceous Pneumoconiosis in a desert area of Sunan County Gansu Province China
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Temperature Regulation Effect of Desert Vegetation in Minqin Desert Area
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作者 Chang Zhaofeng Zhang Xiaojuan +3 位作者 Wang Qi Zhang Dekui Duan Xiaofeng Shi Xuegang 《Animal Husbandry and Feed Science》 CAS 2016年第6期364-368,共5页
[ Objective] The paper was to study the effects of desert vegetation on temperature regulation and stabilization in desert area. [ Method] The survey data of quadrats in five kinds of plant communities in Minqin deser... [ Objective] The paper was to study the effects of desert vegetation on temperature regulation and stabilization in desert area. [ Method] The survey data of quadrats in five kinds of plant communities in Minqin desert area were preliminarily estimated. [Result] Desert vegetation had the ecological functions of regulating desert temperature and stabilizing sharp increase of temperature, especially the irreplaceable ecological function of slowing down sandstorm each spring in northwest China compared to physical sand-fixatian measures. The air humidity in forest region was relatively large, and the climate was more stable. The climate in desert area was dry, with intense changes in air temperature. Although the solar radiation utilization rate of desert vegetation per unit area in Minqin oasis fringe was 5.8% of that of 100% coverage vegetation, it had non-ignorable significance in regulating temperature of local desert. Regulating temperature was one of the ecological functions of desert vegetation. Previous studies only considered wind proof and sand-fixation functions of desert vegetation, but ignored its temperature regulation effect, and this was the ecological function of vegetation sand control different from physical sand-fixation measures such as sand barrier. [ Conclusion] It has important theoretical guiding significance and practical use value for prevention and control of desertification by studying ecological function of desert plants/vegetation. 展开更多
关键词 Sand-fixatian forest Regulating air temperature Ecological function SANDSTORM Minqin desert area
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Particle Size of Barchan Dune in Hexi Desert Area and Its Relationship with Wind Speed
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作者 Chang Zhaofeng Han Shenghui +4 位作者 Tang Jinnian Wang Qi Zhang Dekui Zhang Jianhui Wang Qiangqiang 《Animal Husbandry and Feed Science》 CAS 2016年第4期239-245,共7页
[ Objective ] The paper was to study the particle size characteristics of barchan dune and its formation mechanism in Hexi desert area d Gansu. [ Method] Through particle size measurement and wind speed flow field obs... [ Objective ] The paper was to study the particle size characteristics of barchan dune and its formation mechanism in Hexi desert area d Gansu. [ Method] Through particle size measurement and wind speed flow field observation d dune, the particle size differences of various sampling plots and various parts of dune were analyzed using analysis of variance, and the relationship between particle size and wind speed was analyzed using correlation coefficient method. [ Result] ( 1 ) Barehan dune and barehan chains in Hexi desert area of Gansu were mainly consisted of fine sands and medium sands at the depth of 0 -5 cm: the sand particle in Gulang desert area was fine, which had significant difference with that in Jinchang, Linze, Jinta and Minqin desert areas. (2) Medium sands gradually increased from the bottom of windward slope to the dune peak in both barchan dune and barchan chain. On the windward slope of barehan dune, fine sands gradual- ly increased from the middle to both sides, while coarse sands and medium sands gradually decreased. On the windward slope of barehan chain, fine sands first de- creased then increased from the middle to NE side, but first increased then decreased from the middle to SW side. (3) In terma of particle size, there were great variations between fine sands and coarse sands ; for dune parts, there were great variations between dune peak and leewant slope toe; for dune types, the variation of fine sands in various parts of barchan chain was greater than that of barchan dune, while differentiation degree of medium sands and fine sands was greater than that of barchan dune. The particle size of fine sands was positively correlated with wind speed, and that of medium sands was negatively correlated with wind speed. [ Conclusion] The formation environment of particle size of berehan dune mainly included sand source and dynmnic source, and wind speed was the dynamic source for particle size distribution of barchan dune. 展开更多
关键词 Barchan dune Barehan chain Particle size Wind speed Heixi desert area of Gansu
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Stability and Ecological Effects of Main Plant Communities in Minqin Desert Area
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作者 Chang Zhaofeng Duan Xiaofeng +3 位作者 Han Fugui Zhong Shengnian Wang Qiangqiang Zhang Jianhui 《Animal Husbandry and Feed Science》 CAS 2015年第3期191-196,共6页
[ Objective ] To elucidate the change trend in stability and ecological effects of plant communities in desert along with global wanning. [ Method ] The data of site-specific observation on five main plant communities... [ Objective ] To elucidate the change trend in stability and ecological effects of plant communities in desert along with global wanning. [ Method ] The data of site-specific observation on five main plant communities at ten plots in Minqin desert area were used to analyze the stability and ecological effects of desert plant communities by using two indicators vegetation coverage and projective cover degree. [ Results ] The vegetation coverage of Artemisia arenaria and Ephedra przewalskii, and the projective cover degree of A. arenaria and man-made Haloxylon ammodendron forest decreased remarkably; and the vegetation coverage of Ni- traria tangutorum was also decreased to some extent. [ Conduslon] (1) The plant communities with poor vegetation coverage gives a relatively strong stability, while that with high vegetation coverage has a relatively poor stability; (2) the yearly precipitation is the determinant of vegetation coverage and projective cover deglee; (3) the ecological function is found to be most remarkable in per unit area N. tangutorum, followed by E. przewalskii and N. tangutorum +H. ammodendron, and least in per unit area A. Arenaria. The vegetation is sparse in desert and plant branches does not distribute regularly, thus the crown-based vegetation coverage can not reflect the actual surface coverage. 展开更多
关键词 Plant communities STABILITY Ecological effects Minqin desert area
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Studying surface structure in desert areas using multiple kinds of surface wave data 被引量:1
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作者 Cheng Suo Gang Tian Zhanjie Shi 《Applied Geophysics》 SCIE CSCD 2007年第1期1-7,共7页
浅表面波浪方法主要在非荒芜的区域在环境、工程的地球物理为表面速度结构的调查被使用。为 Takelamagan 荒芜的区域的特殊地质的特征,我们使用处理多信道的浅表面波浪的方法记录在荒芜的区域决定近的表面速度结构的表面波浪(MASW ) ... 浅表面波浪方法主要在非荒芜的区域在环境、工程的地球物理为表面速度结构的调查被使用。为 Takelamagan 荒芜的区域的特殊地质的特征,我们使用处理多信道的浅表面波浪的方法记录在荒芜的区域决定近的表面速度结构的表面波浪(MASW ) 的多信道的分析。我们也处理,分析,并且比较在从在区域的油探索射击集合提取的许多踪迹记录的表面波浪。我们证明 MASW 方法能决定在荒芜的区域和许多踪迹记录的详细浅速度结构能被用来变得详细深地质的结构。二不同数据集的联合能获得准确速度结构上面在调查区域的 60 m 深度。 展开更多
关键词 沙漠地区 近地表结构 表面波 数据分析 多道分析法
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Comparative Analysis of Wind break and Sand fixation Functions of Several Main Forage Plants in Minqin Desert Area
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作者 Li Xiaolin Chang Zhaofeng +2 位作者 Wang Qi Han Fugui Duan Xiaofeng 《Animal Husbandry and Feed Science》 CAS 2017年第5期334-338,共5页
[Objective] The paper was to study wind-break and sand-fixation functions of forage plants in desert area. [Method]Based on the survey data of four major wind-break and sand-fixation plants( Haloxylon ammondendron,Art... [Objective] The paper was to study wind-break and sand-fixation functions of forage plants in desert area. [Method]Based on the survey data of four major wind-break and sand-fixation plants( Haloxylon ammondendron,Artemisia arenaria,Nitraria tangutorum and Ephedra przewalskii) in Minqin desert area,the longitudinal section area and the sandpile volume of an individual plant and per unit area were calculated. The wind-break and sand-fixation functions of four major plant communities were comparatively analyzed. [Result] The wind-break functions of an individual plant( cluster) successively were N. tangutorum > H. ammondendron > A. arenaria and E. przewalskii; the sand-fixation functions of an individual plant( cluster) successively were N. tangutorum > E. przewalskii; the wind-break functions per unit area successively were A. arenaria > H. ammondendron > N. tangutorum > E. przewalskii; the sand-fixation functions per unit area were N. tangutorum > E. przewalskii; the wind-break and sand-fixation function per unit area were N. tangutorum > A. arenaria > H. ammondendron >E. przewalskii.[Conclusion]A. arenaria can be selected for only wind-break,and N. tangutorum can be chosen for only sand-fixation. If given consideration to both,N. tangutorum and A. arenaria must be selected. 展开更多
关键词 WIND BREAK and SAND FIXATION forest Longitudinal section area WIND BREAK FUNCTION SAND FIXATION FUNCTION Minqin desert area
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Experiment on Dust Flux During Duststorm Periods over Desert Area 被引量:1
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作者 张宏升 朱好 +3 位作者 彭艳 康凌 陈家宜 Soon-Ung PARK 《Acta meteorologica Sinica》 SCIE 2008年第2期239-247,共9页
The present study investigates the characteristics of turbulent transfer and the conditions for dust emission and transport using the dust concentration and micrometeorological data obtained during dust events occurri... The present study investigates the characteristics of turbulent transfer and the conditions for dust emission and transport using the dust concentration and micrometeorological data obtained during dust events occurring in the spring of 2004 over the Hunshandake desert area. The turbulent exchange coefficients and turbulent fluxes of momentum and heat are calculated. The relationships between dust flux, friction velocity, and wind speed are also explored. The results show that thermal turbulence is dominant during daytime of non-dusty days. The dynamic turbulence increases obviously and the sensible heat flux reduces by different degrees during dust events. There is an efficient downward transfer of momentum before duststorm occurrence, and both the dynamic turbulence and the thermal turbulence are important in the surface layer. The dynamic turbulence even exceeds the thermal turbulence during severe duststorm events. The values of dust flux vary in the range of -5 5, -30 30, and -200-300 μg m^-2 s^-1 during non-dusty days, blowing dust, and duststorm events, respectively. A slight upward transport of dust is observed during non-dusty days. The dust flux gradually varies from positive to negative during duststorm periods, which indicates the time evolution of dust events from dust rising to stably suspending and then deposition. The dust flux is found to be proportional to u*^3. The threshold values of wind speed and friction velocity are about 6 and 0.4 m s^-1, respectively. 展开更多
关键词 turbulent transfer dust flux threshold friction velocity dust event Hunshandake desert area
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Lake Area Changes and the main causes in the hinterland of Badain Jaran Desert during 1973–2010,China 被引量:4
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作者 ZhenYu Zhang NaiAng Wang +1 位作者 Ning Ma Yue Wu 《Research in Cold and Arid Regions》 CSCD 2014年第1期22-29,共8页
Lake area information in the Badain Jaran Desert in 1973, 1990, 2000, and 2010 was obtained by visual interpretation and water index analysis of remote sensing images, based on the spatial and temporal characteristics... Lake area information in the Badain Jaran Desert in 1973, 1990, 2000, and 2010 was obtained by visual interpretation and water index analysis of remote sensing images, based on the spatial and temporal characteristics of lake area changes during 37 years. Results indicated that the nttmber of lakes declined from 94 to 82 and the total surface area was reduced by 3.69 km2 during 1973-2010. The desert lake area reduced by different degrees in different periods, but this occurred most rapidly during 1973-1990. According to the statistics of lake area changes, lake area decreases mainly occurred in the lakes with areas less than 0.2 km2, while the areas of lakes greater than 0.9 km2 only fluctuated. The changes of lake areas were probably due to changes in the quantity of underground water supplies rather than the effects of local climate change or human factors. 展开更多
关键词 Badain Jaran desert LAKE area change remote sensing climate change groundwater recharge change
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Study on the Resistance Indexes of Four Kinds of Desert Plants in Qinghai Lake Area 被引量:1
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作者 SHI Hui-lan Department of Biosciences,Qinghai University,Xining 810016,China 《Meteorological and Environmental Research》 CAS 2011年第5期54-57,共4页
[Objective] The research aimed to study the resistance of four kinds of desert plants in Qinhai Lake area.[Method] By contrasting the resistance indexes of four kinds of plants which included Ephedra intermedia,Stelle... [Objective] The research aimed to study the resistance of four kinds of desert plants in Qinhai Lake area.[Method] By contrasting the resistance indexes of four kinds of plants which included Ephedra intermedia,Stellera chamaejasme,Achnatherum splendens and Xanthopappus subacaulis,the resistance of four kinds of plants in Qinghai Lake area was analyzed.The resistance indexes included the soluble protein,MDA,free Pro content and the activities of SOD,POD,CAT.Moreover,the resistance of four kinds of plants was evaluated comprehensively by using Fuzzy membership function method.[Result] Under the low-temperature and arid adversity in Qinghai Lake area,SOD activity presented as Stellera chamaejasme>Xanthopappus subacaulis>Ephedra intermedia>Achnatherum splendens,and CAT activity presented as Stellera chamaejasme>Xanthopappus subacaulis>Achnatherum splendens>Ephedra intermedia.Under the same high-salt environment,CAT activity of Stellera chamaejasme was eight times higher than that of Ephedra intermedia.It illustrated that the salt resistance of Stellera chamaejasme was stronger than that of Ephedra intermedia.The free Pro content showed as Xanthopappus subacaulis>Ephedra intermedia>Stellera chamaejasme>Achnatherum splendens.Under the same adversity,Pro content of Ephedra intermedia was 2.83 times of Stellera chamaejasme.It was because that MDA content in Stellera chamaejasme was the lowest,and the membranous peroxide harm was the smallest.It caused that Pro content (stress penetration material) was low.It also illustrated that the resistance of Stellera chamaejasme was stronger than that of Ephedra intermedia.The comprehensive evaluation of Fuzzy membership function showed that the resistance presented as Xanthopappus subacaulis>Stellera chamaejasme>Ephedra intermedia>Achnatherum splendens.[Conclusion] The research provided the theory basis for the breeding of drought-resistance new variety and the development of good germ plasm resource in Qinghai Lake area. 展开更多
关键词 Qinghai Lake area desert plant RESISTANCE China
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Geochemical Stream Sediment Survey in the Wadi Umm Rilan Area,South Eastern Desert,Egypt:A New Occurrence for Gold Mineralization 被引量:2
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作者 Mohamed Abdallah Gad DARWISH 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期1041-1062,共22页
The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and tr... The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements. 展开更多
关键词 geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southEastern desert EGYPT
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Rehabilitation and Sustainable Use Pattern of Rocky-desertified Land in Southwest China’s Poverty-stricken Karst Mountainous Areas——A Case Study in Benggu Township, Xichou County, Yunnan, China 被引量:11
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作者 YANG Zisheng LIU Yansui +2 位作者 BAO Guangjing LI Zhiguo HE Yimei 《Journal of Mountain Science》 SCIE CSCD 2006年第3期237-246,共10页
The rocky desert in a karst area directly causes the lack of soil, water and forest, hence leading to the poverty there. In 1990, the villagers from the Muzhe Village in Benggu Township, Xichou County, Yunnan declared... The rocky desert in a karst area directly causes the lack of soil, water and forest, hence leading to the poverty there. In 1990, the villagers from the Muzhe Village in Benggu Township, Xichou County, Yunnan declared a war against rocky desert in an attempt to ask the fields for more yields. They invented a distinctive land rehabilitation and sustainable use pattern called “transforming heavenand earth” that had been practiced in Southwest China’s karst areas. The key mechanism of the pattern was to develop terraced fields with well conserved soil, water and fertility by exploding rocks in the fields, building stone walls, gathering more soil, and improving soil quality and productivity for the fields in combination with building of irrigation facilities and roads, as well as with forestation and agriculture structure adjustment. The purpose of the pattern was to alleviate poverty in the karst areas by improving soil productivity and promoting agriculturaldevelopment. A typical area was studied with the help of Participatory Rural Appraisal (PRA) and the pattern was carried out there for fifteen years, have produced excellent ecological benefits and good economic benefits. Its application in the area approved that it was a sustainable land use pattern for rocky desert areas. 展开更多
关键词 岩溶 沙漠 土地利用 西南地区 多山地区
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Land Deterioration of a Semi-desert Grazing Area in the North-Eastern Zone of Libya (Cyrenaica)
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作者 Yacoub Mohamed EL-Barasi Manam Waft Barrani Rebeh Otman Al Tajoury 《Journal of Environmental Science and Engineering(B)》 2013年第6期357-373,共17页
关键词 土地退化 利比亚 半荒漠地区 东北区 土壤种子库 一年生植物 植被覆盖度 放牧
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Depth and Structural Parameters Determination of the Sedimentary Basin in Atmur Nuqra Area, South Eastern Desert, Egypt Using Aeromagnetic Data Analysis
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作者 Ahmed A. Elhusseiny Asmaa A. Azzazy 《Geomaterials》 2021年第2期23-41,共19页
The study area is located at the south of the eastern desert of Egypt between latitudes 24<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span><... The study area is located at the south of the eastern desert of Egypt between latitudes 24<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span></span>N to 25<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span></span>N and longitudes 33<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span></span>E to 33<span style="white-space:nowrap;"><span style="white-space:nowrap;">&#176;</span></span>50'E covering an area of about 9407 km<sup>2</sup>. The study area is mainly covered with sediments whose age extends from the upper Cretaceous to the Quaternary, in addition to the presence of some basement rocks such as younger granites, metasediments and metagabbro. The research aims essentially to determine the thickness of the sedimentary basin by determining the depth to the top of basement and delineating the subsurface geological structures which affected this sedimentary basin. The Euler depth map exhibited that the north parts of the area have shallow depth values from 1000 m to 2000 m. The southern parts also show a shallow to moderate depths ranging from 1000 m to 2400 m. The deepest parts are located at the middle and at the western parts and are ranging in value from 3000 m to more than 4000 m. The horizontal derivative and tilt derivative techniques proved that the most effective trends all over the study area are NW-SE and NE-SW directions as mentioned in geologic lineaments map. The basement tectonic map shows clearly all the faults affected the area. It shows that there are many high blocks trending mainly in NW-SE and NE-SW directions. All high blocks surround a large sedimentary basin reaches depth of about more than 4000 m. All the results produced from 2D-modeling illustrate that the sedimentary basinal area (G2) is the deeper basin all over the area and it is controlled by some faults and fractures. 3D inversion was used and resulted in that the area of study have many high blocks at shallow to moderate depths which surrounding a large sedimentary basinal area with very deep depth values. All the techniques which applied in this research led to that the largest sedimentary basin is located at the center of the study area with NW-SE trend and depth value of about 4000 m. 展开更多
关键词 Subsurface Structure Depth to Basement Magnetic Interpretation Atmur Nuqra area Eastern desert
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民勤荒漠区油莎豆种质资源筛选研究
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作者 康才周 朱淑娟 +3 位作者 安红燕 王家奇 姜生秀 张德魁 《安徽农业科学》 CAS 2024年第11期19-23,共5页
[目的]筛选出适宜在民勤荒漠区推广种植的高产高油油莎豆,对民勤产业发展具有重要的战略意义。[方法]引入10个不同种质资源油莎豆,观测其出苗率,测量产量和油脂含量,同时运用SPSS软件对比分析不同种源地油莎豆种质资源的产量、油酸含量... [目的]筛选出适宜在民勤荒漠区推广种植的高产高油油莎豆,对民勤产业发展具有重要的战略意义。[方法]引入10个不同种质资源油莎豆,观测其出苗率,测量产量和油脂含量,同时运用SPSS软件对比分析不同种源地油莎豆种质资源的产量、油酸含量,以及人体不能合成而必须从膳食中补充的亚油酸和亚麻酸含量。[结果]不同种源地油莎豆种质资源之间产量有差异;不同种源地油莎豆种质资源之间油酸、亚油酸含量差异显著;引入的10个不同种源地油莎豆种质资源中,出苗率均超过90%,产量均超过6000.0 kg/hm^(2),其中有4个油莎豆种质资源的油酸含量位于最佳食用油脂肪酸组成区间,其亚油酸和亚麻酸含量由高到低排序为河南油莎豆、西班牙油莎豆、中科院油莎豆6号、武汉1号。[结论]适宜在民勤荒漠区推广种植的高产高油油莎豆种质资源依次为河南油莎豆、西班牙油莎豆、中科院油莎豆6号和武汉1号。 展开更多
关键词 油莎豆 种质资源 筛选 荒漠区 推广
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