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Research Advances in Allelopathy of Plants in Arid Desert Regions of Northwest China 被引量:1
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作者 Wang Fanglin Yu Qiushi +4 位作者 Chai Chengwu Wang Lide Wei Xiaohong Zhang Jinchun Zhang Yinhua 《Meteorological and Environmental Research》 CAS 2016年第3期49-55,共7页
To investigate allelopathy of plants in desert ecosystems, related research achievements obtained in recent years, reported allelopathic plants, allelochemicals and releasing ways of alleochemicalds were summarized, a... To investigate allelopathy of plants in desert ecosystems, related research achievements obtained in recent years, reported allelopathic plants, allelochemicals and releasing ways of alleochemicalds were summarized, and then the key problems of research into allelopathic plants in desert ecosystems were indicated. It was considered that the research of allelopathy of plants in desert regions has just started in China, and plants with atlelopathic potential were found in the Compositae, Leguminosae, Rosaceae, Scrophulariaceae and Gramineae; plants in desert regions re- lease allelochemicals mainly via natural volatilization, which is closely related to their growing environment; allelochemicals such as alkaloids, fla- vonoids, terpenoids have been identified. This study can provide theoretical basis and practical value for reasonable adoption of protection meas- ures of desert plants and comprehensive control of desertification. 展开更多
关键词 Arid desert regions ALLELOPATHY ALLELOCHEMICALS Research advances China
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Response of Grassland Vegetation to Air Temperature and Precipitation in Minqin Desert Region
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作者 CHANG Zhao-feng HAN Fu-gui +1 位作者 ZHONG Sheng-nian WANG Da-wei 《Animal Husbandry and Feed Science》 CAS 2013年第1期41-49,共9页
[ Objective] This paper aims to analyze response characteristics of desert grassland vegetation to climate change. [ Method] The responses of grassland vegetation in desert region to air temperature/precipitation chan... [ Objective] This paper aims to analyze response characteristics of desert grassland vegetation to climate change. [ Method] The responses of grassland vegetation in desert region to air temperature/precipitation changes were analyzed by phenological observations since 1974, observation data conceming vegetation samples and meteorological data during the same period. The changing trend significance was denoted by linear trend line and its regression significance. The interrelation between the two variables was indicated by correlation coefficients. Data were analyzed by the software SPSS 13.0. [Result] (1) The rising rate of annual average temperature in the Minqin desert area since 1961 was greater than both the global level and Ghina's level over the past century. (2) Desert plants' response to temperature changes were mainly displayed as the advance of spring phenology, the delay of autumn phenology and the extension of growing duration. Plants' main response to precipitation changes was that vegetation coverage and pure coverage were decreasing along with precipitation reducing. (3) Both the vegetation coverage and pure coverage mainly had a positive correlation with the annual precipitation. Plant density mostly had a positive correlation with the precipitation in September. (4) The impact of rising temperature on plant phenology in spring was greater than that in autumn. [ Conclusion] The effects of temperature changes on desert grassland plants were the advance of spring phenology, the delay of autumn phenology, the extension of growing season and longer plant growing period than that in other reports. The responses of desert grassland vegetation to precipitation changes were that both vegetation coverage and pure coverage were decreasing along with precipitation reducing, and plant density fluctuated along with precipitation change. 展开更多
关键词 TEMPERATURE PRECIPITATION Plant phenology Vegetation coverage Grassland vegetation Minqin desert region
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Temporal and spatial changes of residential land in the Yuyang desert region of northern Shaanxi Province in recent 20 years 被引量:1
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作者 Xiangsheng YI Yanyu YIN Yaojie YUE 《Frontiers of Earth Science》 SCIE CAS CSCD 2012年第3期250-260,共11页
It is very important to understand the temporal and spatial changes of residential land for the improvement of human settlement environment. Based on the three TM images of 1986, 1996 and 2005 and other assistant maps... It is very important to understand the temporal and spatial changes of residential land for the improvement of human settlement environment. Based on the three TM images of 1986, 1996 and 2005 and other assistant maps, the temporal and spatial characteristics of residential land in the Yuyang desert region of northern Shaanxi Province of China were analyzed by using geographical information System (GIS) and remote sensing (RS) technology. Some important conclusions were obtained, which mainly contained four aspects as follows. 1) The area of residential land in the Yuyang desert region increased 956.07 hm2 in total, and the changes of residential land among the townships were different with four various change trends. The expansion speeds in the Yuyang Township and Qinhe Township were the biggest from 1986 to 1996 and from 1996 to 2005, respectively. The expansion intensities in other townships were below 0.1%, except the Yuyang Township. 2) The number of residential land patches increased 2847, while the average area and perimeter of residential land patches decreased 0.304 hm2 and 60.78 m during 1986-2005, respectively. The residential land patches also displayed four different changes from 1986 to 2005 among the townships. 3) The residential land mainly distributed in the middle of Yuyang Township and Mahe Township, and the interface of Jinjitan Township and Mengjiawan Township. The total spatial pattern of residential land was relative stability, but the significant changes of residential land were found in the Yuyang Township and its vicinities during 1986-2005. 4) Three distribution patterns of residential land at the micro scale were categorized from the 100 typical villages in the study area. The number of villages in the pattern 1 increased, while the pattern 2 and pattern 3 decreased in recent 20 years, which implicated the adaptation of humans to the habitation environment. This research would provide scientific references fbr harmonizing the human-land relationship, optimizing the residential land spatial distribution patterns and constructing the well human settlement environment in the desert regions. 展开更多
关键词 residential land temporal change spatialpattern Yuyang desert region
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Annual plants in arid and semi-arid desert regions 被引量:1
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作者 Xuehua LI Xiaolan LI +2 位作者 Deming JIANG Zhimin LIU Qinghe YU 《Frontiers in Biology》 CSCD 2008年第3期259-264,共6页
Annual plants are the main vegetation in arid and semi-arid desert regions.Because of their unique traits,they are the optimal experimental subjects for eco-logical studies.In this article,we summarize annual plants’... Annual plants are the main vegetation in arid and semi-arid desert regions.Because of their unique traits,they are the optimal experimental subjects for eco-logical studies.In this article,we summarize annual plants’seed germination strategies,seedling adaptability mechanism to environments,seed dispersal,and soil seed banks.We also discuss the biotic and abiotic factors affecting the composition and dynamics of annual plant populations and communities.Because annual plants have important ecological functions in desert vegetation systems,this study on annual plants will be of great benefit to the conservation and restoration of desert ecosystems,the rational utilization of resources,and the sustainable development of desert regions. 展开更多
关键词 desert region annual plants seed germination SEEDLING seed bank population dynamics
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Palaeomonsoon vicissitudes in eastern desert region of China since last interglacial period 被引量:2
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作者 董光荣 王贵勇 +2 位作者 李孝泽 陈惠忠 金炯 《Science China Earth Sciences》 SCIE EI CAS 1998年第2期215-224,共10页
Based on the geological records, the palaeomonsoon in eastern desert region of China is divided into three major evolution stages, i.e. summer monsoon prevailing stage of last interglacial period (130-70kaB.P.), winte... Based on the geological records, the palaeomonsoon in eastern desert region of China is divided into three major evolution stages, i.e. summer monsoon prevailing stage of last interglacial period (130-70kaB.P.), winter monsoon prevailing stage of last glacial period (70-10 kaB.P.), and unstable summer monsoon prevailing stage of postglacial period (10 kaB.P. to present) and further divided into several substages. The conversion between summer monsoon and winter monsoon in the region is dominated by the sudden change process. The north limit of summer monsoon in the region retreated to the north limit of sandy loess zone of the Loess Plateau in the last glacial period from the Mazong Mts.-Ulan Bator of last interglacial period, then it entered Shandan-Yabrai region in the optimum period of the Holocene, and finally it retreated to the present extended line from north piedmont of the Yinshan Mts to Hulun Buir. This shows that the summer monsoon caused by East Asian monsoon circulation tends to be weakened fluctuationally. However, the factors affecting the monsoon vicissitudes are complex, so special attention should be paid to the study of the short-period climatic fluctuations of the Holocene. 展开更多
关键词 LAST INTERGLACIAL period EASTERN desert region MONSOON vicissitude.
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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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Spatial-temporal dynamics of desert vegetation and its responses to climatic variations over the last three decades:a case study of Hexi region in Northwest China 被引量:10
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作者 YANG Xuemei LIU Shizeng +6 位作者 YANG Taibao XU Xianying KANG Caizhou TANG Jinnian WEI Huaidong Mihretab G GHEBREZGABHER LI Zhiqi 《Journal of Arid Land》 SCIE CSCD 2016年第4期556-568,共13页
Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inv... Analysis of spatial-temporal variations of desert vegetation under the background of climate changes can provide references for ecological restoration in arid and semi-arid areas. In this study, we used the Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data from 1982 to 2006 and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data from 2000 to 2013 to reveal the dynamics of desert vegetation in Hexi region of Northwest China over the past three decades. We also used the annual temperature and precipitation data acquired from the Chinese meteorological stations to analyze the response of desert vegetation to climatic variations. The average value of NDVImax (the maximum NDVI during the growing season) for desert vegetation in Hexi region increased at the rate of 0.65x10-3/a (P〈0.05) from 1982 to 2013, and the significant increases of NDVImax mainly appeared in the typical desert vegetation areas. Vegetation was significantly improved in the lower reaches of Shule and Shiyang river basins, and the weighted mean center of desert vegetation mainly shifted toward the lower reaches of the two basins. Almost 95.32% of the total desert vegetation area showed positive correlation between NDVImax and annual precipitation, indicating that precipitation is the key factor for desert vegetation growth in the entire study area. Moreover, the areas with non-significant positive correlation between NDVImax and annual precipitation mainly located in the lower reaches of Shiyang and Shule river basins, this may be due to human activities. Only 7.64% of the desert vegetation showed significant positive correlation between NDVImax and annual precipitation in the Shule River Basin (an extremely arid area), indicating that precipitation is not the most important factor for vegetation growth in this basin, and further studies are needed to investigate the mechanism for this phenomenon. 展开更多
关键词 desert vegetation NDVI global warming spatial-temporal variations Hexi region
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URANIUM MINERALIZATION IN THE MUSCOVITE-RICH GRANITES OF THE SHALATIN REGION, SOUTHEASTERN DESERT, EGYPT
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作者 GEHAD M. SALEH 《Chinese Journal Of Geochemistry》 EI CAS 2006年第1期1-15,共15页
The younger granitoids of the Shalatin district in the Southeastern Desert of Egypt, are of biotite and two-mica granite compositions. The geochemistry of rare-earth elements (REE), yttrium, thorium and uranium forms ... The younger granitoids of the Shalatin district in the Southeastern Desert of Egypt, are of biotite and two-mica granite compositions. The geochemistry of rare-earth elements (REE), yttrium, thorium and uranium forms the basis for many important methods to reconstruct igneous petrogenesis. Since the recognition that REE, Y, Th, U-rich accessories may play an important role in controlling the geochemistry of crustal melts, a considerable amount of work has been done in an attempt to understand their effects. However, this effort has been almost exclusively focused on three minerals: zircon, monazite and apatite. Nevertheless, the variety of REE-Th-U-rich accessories in granite rocks are neither limited to these three minerals nor are they always the main REE, Y, Th carriers. The geochemistry of REE, Y, Th and U reflects the behavior of accessories and some key major minerals such as garnet and feldspars, and may therefore give valuable information about the conditions of partial melting, melt segregation and crystallization of granite magmas in different crustal regimes. The geochemistry of U and Th during magmatic differentiation has been studied in many granites from different areas and it has been known that the U and Th contents of granitic rocks generally increase during differentiation, although in some cases they decrease. The Th/U ratio can either increase or decrease, depending on redox conditions, the volatile content or alteration by endogene or supergene solutions. The accessory assemblage of muscovite-rich granites and high-grade rocks is composed of monazite, xenotime, apatite, Th-orthosilicate, secondary U-mineralization and betafite-pyrochlore. REE, Y, Th and U are not suitable for geochemical modeling of granitoids by means of equilibrium-based trace element fractionation equations, but are still useful petrogenetic tools. 展开更多
关键词 矿化作用 稀土元素 花岗岩 沙漠 埃及
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2010–2020年塔里木盆地南部荒漠草地凋落物回收量月动态数据集
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作者 王鹏 李向义 +2 位作者 热甫开提 林丽莎 曾凡江 《中国科学数据(中英文网络版)》 CSCD 2024年第2期227-237,共11页
中国科学院新疆策勒荒漠草地生态系统国家野外科学观测研究站(以下简称“策勒站”)地处塔里木盆地南缘,南依昆仑山,北临我国最大的塔克拉玛干沙漠。具有植被群落简单,土壤有机质积累缓慢等特点。凋落物是该区域重要的养分来源。基于对... 中国科学院新疆策勒荒漠草地生态系统国家野外科学观测研究站(以下简称“策勒站”)地处塔里木盆地南缘,南依昆仑山,北临我国最大的塔克拉玛干沙漠。具有植被群落简单,土壤有机质积累缓慢等特点。凋落物是该区域重要的养分来源。基于对策勒站荒漠植物群落的长期定位观测,通过对不同植物凋落物器官(枝、叶、果)分组,本文整理统计得到2010–2020年塔里木盆地南部荒漠草地凋落物的回收量月动态数据,同时记载了观测场群落以及土壤养分的年度变化情况。数据的产生严格遵照CERN生物观测规范执行,数据的审核及质量控制由台站与分中心质控人员共同完成。本数据集以期为深入研究塔里木盆地南部荒漠草地凋落物动态变化提供基础数据,为了解和评估极端干旱荒漠生态系统养分循环过程提供理论支撑。 展开更多
关键词 极端干旱区 荒漠草地生态系统 凋落物月动态 塔里木盆地南部 土壤养分循环
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Noah-MP陆面模式对干旱区不同下垫面水热通量模拟评估
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作者 杨扬 杨启东 《沙漠与绿洲气象》 2024年第1期28-37,共10页
基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关... 基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关系数均>0.98,泰勒评分>0.93。感热的泰勒评分(0.809)>潜热的泰勒评分(0.504),对辐射及湍流通量的变化特征、峰谷值与观测值总体一致,模拟效果较好。模拟的5 cm土壤湿度对降水过程有明显的响应,表现出明显的冷暖季差异,但其模拟性能仍有待改进。Noah-MP模式模拟的干旱区农田下垫面辐射通量及各层土壤温度的相关系数均>0.98,泰勒评分>0.58,模拟效果较理想。但模拟的潜热通量及各层土壤湿度较观测值偏低,尤其在生长季模拟性能不理想。Noah-MP模式对干旱区荒漠下垫面水热通量的模拟性能优于农田下垫面,优化和发展模式水文过程的参数化方案,在模式中考虑人为作用,是提高干旱区陆面过程模式模拟能力的重要方向。 展开更多
关键词 干旱区 Noah-MP模式 水热通量 荒漠和农田下垫面
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荒漠浅覆盖区萤石矿定位预测技术研究
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作者 刘诚 唐卫东 +4 位作者 杨凯 李含 贺景龙 姚川 李新斌 《西北地质》 CAS CSCD 北大核心 2024年第4期144-156,共13页
北山地区是中国西北部重要的萤石成矿带,区内成矿地质条件优越,但地处戈壁荒漠,受浅覆盖层影响,地表仅可观察到极少量露头,需开展综合地球物理研究为区域成矿潜力及覆盖区下方矿脉赋存空间进行定位预测研究。以北山成矿带东段花石头山... 北山地区是中国西北部重要的萤石成矿带,区内成矿地质条件优越,但地处戈壁荒漠,受浅覆盖层影响,地表仅可观察到极少量露头,需开展综合地球物理研究为区域成矿潜力及覆盖区下方矿脉赋存空间进行定位预测研究。以北山成矿带东段花石头山地区为示范,采用高精度磁法、激电中梯、地面伽马能谱测量、便携式X射线荧光分析及音频大地电磁测深等技术手段进行综合探测,其中面积性激电和磁法工作可有效识别隐伏赋矿空间分布,地面伽马能谱测量、便携式X射线荧光分析约束赋矿空间的矿化异常,音频大地电磁测深构建了隐伏萤石矿赋存位置深部结构模型,并通过工程验证方法组合的有效性。本研究建立了综合地质-地球物理定位预测技术方法组合,可为北山成矿带及戈壁荒漠浅覆盖区萤石矿定位预测提供理论和技术支持。 展开更多
关键词 隐伏萤石矿 综合物探方法 戈壁荒漠 浅覆盖区 北山成矿带
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北山荒漠戈壁浅覆盖区萤石矿定位技术研究
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作者 刘诚 杨凯 +3 位作者 唐卫东 贺景龙 薛东旭 李含 《地质论评》 CAS CSCD 北大核心 2024年第S01期87-88,共2页
在我国的西北部地区,特别是东天山—北山成矿带中新生界覆盖区广泛分布,仅戈壁、沙漠覆盖区就占据了全国陆地总面积的12.3%。随着东部矿产资源的开发程度日益提高,西北部大面积的戈壁荒漠浅覆盖区有望成为有利的矿产资源接替基地。因此... 在我国的西北部地区,特别是东天山—北山成矿带中新生界覆盖区广泛分布,仅戈壁、沙漠覆盖区就占据了全国陆地总面积的12.3%。随着东部矿产资源的开发程度日益提高,西北部大面积的戈壁荒漠浅覆盖区有望成为有利的矿产资源接替基地。因此,在戈壁、沙漠等中新生界覆盖区开展矿产综合定位预测工作是当前形势下最佳的选择之一。 展开更多
关键词 隐伏萤石矿 综合物探方法 戈壁荒漠 北山成矿带
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干旱荒漠区三种典型灌丛植物凋落物混合分解效应研究
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作者 王海霞 解婷婷 +2 位作者 米雪 肖路臣 单立山 《草地学报》 CAS CSCD 北大核心 2024年第3期869-878,共10页
为探究干旱荒漠区混合凋落物的分解特征,本研究以红砂(Reaumuria soongarica(Pall.)Maxim)、泡泡刺(Nitraria sphaerocarpa Maxim)和珍珠(Salsola passerina Bunge)为研究对象,分析了单一和混合凋落物质量损失率和养分残留率的变化,揭... 为探究干旱荒漠区混合凋落物的分解特征,本研究以红砂(Reaumuria soongarica(Pall.)Maxim)、泡泡刺(Nitraria sphaerocarpa Maxim)和珍珠(Salsola passerina Bunge)为研究对象,分析了单一和混合凋落物质量损失率和养分残留率的变化,揭示了混合凋落物分解的加性与非加性效应。结果表明:各凋落物质量损失率随分解时间延长呈增加趋势;各凋落物C和N残留率随分解时间推移为降低趋势,说明C和N养分元素呈释放模式;混合凋落物质量损失率表现为加性效应,C残留率在分解前期为加性效应,分解末期为拮抗的非加性效应,N残留率在分解前期为拮抗和协同的非加性效应,分解末期为加性效应;凋落物混合后,较高的物种丰富度会导致养分残留率的非加性效应增强。综上,混合凋落物分解中养分变化的混合效应因分解时间而不同,混合凋落物物种丰富度会影响养分元素的混合效应,能改善干旱荒漠生态系统的养分循环。 展开更多
关键词 凋落物分解 干旱荒漠区 非加性效应 拮抗效应 质量损失率
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我国沙漠地区光伏产业与生态治理分析
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作者 尚小伟 武文一 +5 位作者 卫建军 刘建国 张华新 郭浩 时忠杰 李瀚之 《绿色科技》 2024年第4期27-33,共7页
我国沙漠地区目前正在大力发展光伏产业,但是由于其生态脆弱性,光伏产业的落地对沙区生态环境有何种影响至今仍是争议热点。为厘清光伏产业和生态治理的关系,通过对前人研究结果进行归纳总结,从光伏产业的生态问题、治理措施、效益评估... 我国沙漠地区目前正在大力发展光伏产业,但是由于其生态脆弱性,光伏产业的落地对沙区生态环境有何种影响至今仍是争议热点。为厘清光伏产业和生态治理的关系,通过对前人研究结果进行归纳总结,从光伏产业的生态问题、治理措施、效益评估等方面,论述了生态环境在风蚀、沙尘等方面对光伏产业的影响,以及光伏产业运行生产后对周边土壤、植被及小气候的影响,同时归纳总结了沙区光伏产业包括沙地整地、锁边林带、工程固沙、植物固沙以及光伏桩防护等方面的生态治理措施。针对以上问题,针对光伏产业规划选址,提出了将社会效益、生态效益共同纳入考虑范围的综合选址策略;针对光伏产业发展提出了开发多产业复合模式,促进经济、资源、环境的全面协调可持续发展;针对环境保护,分别在建设期和运营期提出了合理施工、制定生态保护应急预案等方案,以及产业全周期生态保护的发展建议。以期为沙区的合理利用提供技术支撑,助力落实沙区“发展为要、生态优先”的发展理念。 展开更多
关键词 光伏 沙漠地区 生态治理 绿色能源
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Soil restoration research advances of artificial sand-binding vegetation ecosystem in the Tengger Desert, Northern China 被引量:3
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作者 LiWen Yang LiChao Liu +1 位作者 DaYong Wang YongQing Zhang 《Research in Cold and Arid Regions》 2010年第4期279-287,共9页
Soil plays an important role in desert ecosystem, and is vital in constructing a steady desert ecosystem. The management and restoration of desertified land have been the focus of much discussion. The soil in Shapotou... Soil plays an important role in desert ecosystem, and is vital in constructing a steady desert ecosystem. The management and restoration of desertified land have been the focus of much discussion. The soil in Shapotou desert region has developed remarkably since artificial sand-binding vegetation established in 1946. The longer the period of dune stabilization, the greater the thickness of microbiotic crusts and subsoil. Meanwhile, proportion of silt and clay increased significantly, and soil bulk density declinced. The content of soil organic matter, N, P, and K similarly increased. Therefore, soil has developed from aeolian sand soil to Calcic-Orthic aridisols. This paper discusses the effects brought about by dust, microbiotic soil crust and soil microbes on soil-forming process. Then, we analyzed the relation between soil formation and sand-binding vegetation evolution, in order to provide a baseline for both research on desert ecosystem recovery and ecological environment governance in arid and semi-arid areas. 展开更多
关键词 Shapotou desert region artificial sand-binding vegetation soil restoration physic-chemical properties
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西北干旱区荒漠戈壁两次极端沙尘事件的对比研究
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作者 董元柱 王天河 +3 位作者 谭睿琦 王思晨 焦英姿 唐靖宜 《干旱气象》 2024年第2期197-208,共12页
为深入理解极端沙尘暴事件的演变过程和驱动因子,结合多源卫星遥感及再分析数据,挑选2007年3月31日(“3·31”事件)和2021年3月14日(“3·14”事件)爆发于西北干旱区荒漠戈壁的两次沙尘暴事件,对比分析了其时空演变、高低空环... 为深入理解极端沙尘暴事件的演变过程和驱动因子,结合多源卫星遥感及再分析数据,挑选2007年3月31日(“3·31”事件)和2021年3月14日(“3·14”事件)爆发于西北干旱区荒漠戈壁的两次沙尘暴事件,对比分析了其时空演变、高低空环流配置、近地面气象要素的变化。结果表明:(1)两次极端事件分别爆发于塔克拉玛干沙漠及戈壁荒漠,均受高低层天气系统影响。其中,“3·31”事件受地面冷锋和高空脊控制,脊前西北冷空气与地面冷锋引起的垂直运动配合,将沙尘往下游输送;而“3·14”事件则受蒙古气旋和高空槽影响,气旋后的偏北风和气旋引发的垂直运动将沙尘卷起至高层大气,并通过槽后西北风将其往下游输送;(2)两次极端沙尘事件均有持续时间长的特点,区别在于“3·31”事件主要受高压脊、均压场和周边地形影响,大气层结稳定,沙尘不易沉降和输送,而“3·14”事件则因中国北部持续性高压导致的偏南风和偏东风阻止了沙尘向下游扩散;(3)两次极端沙尘事件爆发前,塔克拉玛干和戈壁荒漠均出现了高温、降水减少及土壤水分枯竭现象,即强风和干燥土壤。为极端沙尘事件的爆发创造了有利的动力条件和物质基础。 展开更多
关键词 西北干旱区荒漠戈壁 极端沙尘事件 天气系统配置 近地面气象要素
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戈壁滩地区水稳砂砾材料组成设计与工艺控制
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作者 李伟 王涵 王玉果 《建筑技术》 2024年第10期1251-1254,共4页
以新疆G575线巴哈公路项目为依托,通过室内水泥稳定砂砾基层配合比设计、收缩性能试验研究,结合试验段试铺及施工工艺参数指标分析,提出适合戈壁滩地区的水泥稳定砂砾基层组成设计及相关施工工艺,可为同类条件施工项目提供参考。
关键词 戈壁滩地区 水泥稳定砂砾基层 配合比设计
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西北干旱区荒漠植物叶片和细根碳、氮、磷化学计量特征
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作者 陈壹铭 单立山 +4 位作者 马静 王红永 解婷婷 杨洁 马丽 《生态学报》 CAS CSCD 北大核心 2024年第9期3648-3659,共12页
植物的叶片和细根是植物地上部分和地下部分最重要的营养器官,其碳(C)、氮(N)、磷(P)化学计量特征反映了植物的养分限制状况及叶片与细根间的协同作用,开展叶片与细根化学计量关系的研究,对认识植物养分利用策略及元素间平衡关系有重要... 植物的叶片和细根是植物地上部分和地下部分最重要的营养器官,其碳(C)、氮(N)、磷(P)化学计量特征反映了植物的养分限制状况及叶片与细根间的协同作用,开展叶片与细根化学计量关系的研究,对认识植物养分利用策略及元素间平衡关系有重要意义。对西北干旱区21种荒漠植物叶片与细根C、N、P含量进行了测定,分析了C、N、P含量及其计量比在不同生活型及不同器官间的关系。结果表明:1)西北干旱区荒漠植物叶片与细根C含量相对稳定,叶N、P含量高于细根,说明在干旱生境中,植物对养分的分配侧重于地上部分,以完成其正常的生命活动;叶片与细根的N∶P无显著差异,有明显的保守性,表明植物地上与地下部分养分吸收策略与分配规律具有一致性;2)不同生活型植物叶片和细根的C、N、P含量及C∶N、C∶P存在显著差异,灌木与禾草具有较高的C∶N和C∶P,杂类草具有较高的N、P含量,说明灌木与禾草倾向于保守型养分适应策略,杂类草倾向于快速生长的资源竞争策略;3)21种荒漠植物叶片与细根N、P含量间均存在显著的正相关关系,表明西北干旱区荒漠植物体内N、P元素间存在相互作用;4)植物叶片与细根间C、N、P含量及C∶N、C∶P存在等速生长关系,表明植物光合产物和养分在地上与地下部分间的分配具有平行的比例关系,但这种关系受生活型影响。上述结果表明西北干旱区不同生活型植物在恶劣生境中存在不同的养分适应策略,且地上与地下部分的养分利用策略及分配规律存在协同作用,这为进一步认识西北干旱区荒漠植物的养分利用策略提供了试验基础。 展开更多
关键词 生态化学计量 叶片 细根 生活型 西北干旱区 荒漠植物
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Evapotranspiration of an oasis-desert transition zone in the middle stream of Heihe River, Northwest China 被引量:17
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作者 LiWen ZHAO WenZhi ZHAO 《Journal of Arid Land》 SCIE CSCD 2014年第5期529-539,共11页
As a main component in water balance, evapotranspiration is of great importance for water saving and irrigation-measure making, especially in arid or semiarid regions. Although studies of evapotranspiration have been ... As a main component in water balance, evapotranspiration is of great importance for water saving and irrigation-measure making, especially in arid or semiarid regions. Although studies of evapotranspiration have been conducted for a long time, studies concentrated on oasis-desert transition zone are very limited. On the basis of the meteorological data and other parameters(e.g. leaf area index(LAI)) of an oasis-desert transition zone in the middle stream of Heihe River from 2005 to 2011, this paper calculated both reference(ET0) and actual evapotranspiration(ETc) using FAO56 Penman-Monteith and Penman-Monteith models, respectively. In combination with pan evaporation(Ep) measured by E601 pan evaporator, four aspects were analyzed:(1) ET0 was firstly verified by Ep;(2) Characteristics of ET0 and ETc were compared, while the influencing factors were also analyzed;(3) Since meteorological data are often unavailable for estimating ET0 through FAO56 Penman-Monteith model in this region, pan evaporation coefficient(Kp) is very important when using observed Ep to predict ET0. Under this circumstance, an empirical formula of Kp was put forward for this region;(4) Crop coefficient(Kc), an important index to reflect evapotranspiration, was also analyzed. Results show that mean annual values of ET0 and ETc were 840 and 221 mm, respectively. On the daily bases, ET0 and ETc were 2.3 and 0.6 mm/d, respectively. The annual tendency of ET0 and ETc was very similar, but their amplitude was obviously different. The differences among ET0 and ETc were mainly attributed to the different meteorological variables and leaf area index. The calculated Kc was about 0.25 and showed little variation during the growing season, indicating that available water(e.g. precipitation and irrigation) of about 221 mm/a was required to keep the water balance in this region. The results provide an comprehensive analysis of evapotranspiration for an oasis-desert transition zone in the middle stream of Heihe River, which was seldom reported before. 展开更多
关键词 EVAPOTRANSPIRATION pan evaporation water requirement arid region oasis-desert transition zone
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Microclimate and CO_2 fluxes on continuous fine days in the Xihu desert wetland,China
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作者 QianQian GOU JianJun QU ZhiWen HAN 《Journal of Arid Land》 SCIE CSCD 2015年第3期318-327,共10页
The Xihu desert wetland is located in an extremely arid area in Dunhuang,Gansu province of Northwest China.The area is home to an unusual geographic and ecological environment that is considered unique,both in China a... The Xihu desert wetland is located in an extremely arid area in Dunhuang,Gansu province of Northwest China.The area is home to an unusual geographic and ecological environment that is considered unique,both in China and the world.Microclimate is not only related to topography,but is also affected by the physical properties of underlying ground surfaces.Microclimate and CO2 flux have different characteristics under different underlying surface conditions.However,until now,few studies have investigated the microclimate characteristics and CO2 flux in this area.The eddy covariance technique(ECT) is a widely used and effective method for studying such factors in different ecosystems.Basing on data from continuous fine days obtained in the Dunhuang Xihu desert wetland between September 2012 and September 2013,this paper discussed and compared the characteristics of daily microclimate variations and CO2 fluxes between the two periods.Results from both years showed that there was a level of turbulent mixing and updraft in the area,and that the turbulent momentum flux was controlled by wind shear under good weather conditions.The horizontal wind velocity,friction wind velocity and vertical wind velocity were commendably consistent with each other.Air temperature in the surface layer followed an initial decreasing trend,followed by an increasing then decreasing trend under similar net radiation conditions.With changes in air temperature,the soil temperature in the surface layer follows a more obvious sinusoidal fluctuation than that in the subsoil.Components of ground surface radiation during the two study periods showed typical diurnal variations.The maximum diurnal absorption of CO2 occurred at around 11:00(Beijing time) in the Xihu desert wetland,and the concentrations of CO2 in both periods gradually decreased with time.This area was therefore considered to act as a carbon sink during the two observation periods. 展开更多
关键词 eddy covariance microclimate characteristics CO2 flux extremely arid region desert wetland Dunhuang
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