Comparisons between Movement Speed of Main Types of Dunes:A Case Study of Desert Areas in Hexi Region of Gansu Province

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.

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

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 0.65×10–3/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.

THOUGHTS ON CONSTRUCTING THE DEMONSTRATING AREAS OF THE ECOLOGICAL REBUILDING AND ECONOMIC SUSTAINABLE DEVELOPMENT IN HEXI REGION

Based on the field investigations, this paper analyzes systematically the achievements and problems of constructing the demonstrating areas of the ecological rebuilding and economic sustainable development in Hexi, Gansu Province, and then the thoughts on constructing the demonstrating areas are brought forward. It is considered that all kinds of ecological demonstrating areas should be merged in order to construct large scale characterized demonstrating areas which go beyond the district. In other words, in Hexi Region, Zhangye District should be constructed as the largest ecoagriculture demonstrating area of high technology; Wuwei District should be constructed as the largest ecological demonstrating area of agricultural comprehensive exploitation; JiuJia District, which is the shortened form of Jiuquan and Jiayuguan, should be constructed as the largest ecotourism demonstrating area; and Jinchang City should be constructed as the largest ecoindustry demonstrating area. At the same time, the constructing pattern should be selected according to the actual circumstances; science and technology should be applied to construct the demonstrating areas and accelerate the industrialization in the big market. Additionally, it is important to smooth the constructing system and implement the flexible and efficacious running mechanism, and it is suggested that the committee should be organized to administer the ecological demonstrating areas in Hexi Region.

Soil Properties and Characteristics of Soil Aggregate in Marginal Farmlands of Oasis in the Middle of Hexi Corridor Region, Northwest China

The composition and stability of soil aggregate are closely related to soil quality, soil erosion, and agricultural sustainability. In this study, 49 soil samples at the 0-10 cm surface layer were collected from four soil types (i.e., Ari-Sandic Primosols, Calci-Orthic Aridosols, Siltigi-Otrthic Anthrosols, and Ustic Cambosols) in the marginal farmland in the oasis of the middle Hexi Corridor region and was used to determine the characteristics of soil aggregates. The composition of dry- and wet- sieved aggregates and the physical and chemical properties (including soil particle distribution, soil organic carbon (SOC), calcium carbonate (CaCO3), and oxides of Fe3+ and Al3+) of the selected soils were analyzed. The results show that soil particle size distribution is dominated by fine sand fraction in most of soils except Ustic Cambosols. Soil organic carbon concentration is 5.88 ± 2.52 g kg-1 on average, ranging from 4.75 g kg-1 in Ari-Sandic Primosols to 10.51 g kg-1 in Ustic Cambosols. The soils have high calcium carbonate (CaCO3) concentration, ranging from 84.7 to 164.8 g kg-1, which is increased with soil fine particle and organic carbon content. The percentage of > 0.25 mm dry aggregates ranges from 65.2% in Ari-Sandic Primosols to 94.6% in Ustic Cambosols, and large dry blocky aggregates (> 5 mm) is dominant in all soils. The mean weight diameter of dry aggregates (DMWD) ranges from 3.2 mm to 5.5 mm. The percentage of > 0.25 mm water-stable aggregate is from 23.8% to 45.4%. The percentage of aggregate destruction (PAD) is from 52.4% to 66.8%, which shows a weak aggregate stability. Ari-Sandic Primosols has the highest PAD. The distribution and characteristics of soil aggregates are in favor of controlling soil wind erosion. However, the stability of aggregate of all soils is weak and soils are prone to disperse and harden after irrigation. The mass of macro-aggregates and DMWD are positively significantly correlated with the contents of soil clay and silt, soil organic carbon (SOC), CaCO3, and oxides of Fe3+ and Al3+. Soil fine silt and clay, SOC and CaCO3 are important agents of aggregation in this region, and the effect of SOC and CaCO3 on aggregate stability is more significant than that of soil silt and clay. Converting cropland to alfalfa forage land can increase SOC concentration, and in turn, enhance the formation of aggregates and stability. For the marginal farmlands in this fragile ecological area, converting cropland to alfalfa grassland or performing crop-grass rotation is an effective and basic strategy to improve soil structure and quality, to mitigate soil wind erosion, and to enhance oasis agricultural sustainability.

Estimation Study of New Cancer Cases and Deaths in Wuwei, Hexi Corridor Region, China, 2018

Population-based cancer registration data were collected to estimate the cancer incidence and mortality in Wuwei, Hexi Corridor Region, China in 2018. We used the 2011-2013 data to predict the number of new cases and deaths in 2018 and the 2003-2013 data to analyze trends in cancer incidence and mortality. The goal is to enable cancer prevention and control directions. Our results indicated that stomach cancer is the most common cancer. For all cancers combined, the incidence and mortality rates showed significantly increasing trends(+2.63% per year; P < 0.05 and +1.9% per year; P < 0.05). This study revealed a significant cancer burden among the population of this area. Cancer screening and prevention should be performed after an epidemiological study of the cause of the cancer is completed.

气候变化和土地利用覆盖变化对河西地区植被净初级生产力的影响

河西地区不仅是我国重要的生态安全保护优先区,而且是丝绸之路经济带核心地段,开展该地区植被净初级生产力(NPP)评估及驱动力定量分析对于陆地生态系统与大气碳交换、气候变化与人类活动对植被综合作用等研究具有重要的理论价值和现实意义。基于MOD17A3产品数据、土地利用覆盖数据和气象数据,采用R-贡献率和偏相关分析方法,分析了2000—2020年河西地区植被NPP变化特征及土地利用覆被和气候变化对NPP的影响,结果表明:(1)河西地区耕地、水域和居民建筑用地面积整体呈增加趋势,而草地和未利用土地面积有所减少,且2010年后的土地利用覆盖变化(LUCC)整体动态度显著提高,其中,草地、耕地、建设用地和未利用地主导了土地利用类型的相互转换。(2)河西地区整体植被NPP呈增长趋势,2000—2010年和2010—2020年的变化斜率分别为0.86和1.29,且植被NPP具有明显的区域异质性,由东南向西北递减。(3)2000—2020年河西地区LUCC对植被NPP的影响逐渐增大,且气候变化对植被NPP的贡献率普遍高于LUCC,但二者对不同土地利用覆盖类型所起的作用不同,表现为耕地、林地和草地的植被NPP影响因子以气候变化为主导,未利用土地和居民建筑用地的植被NPP影响因子逐步以LUCC为主导。

汉晋时期河西走廊张掖地区的开发研究——以黑水国汉代墓葬为例

黑水国汉代墓葬出土的农具、动物骨骼、农作物遗存和人骨为人们了解河西走廊张掖地区汉晋时期生业经济和农业发展等问题提供了重要证据。通过动物骨骼、农作物遗存鉴定结果和人骨碳氮同位素检测结果,可以揭示汉晋时期黑水国人群的食物结构和生业模式特点。墓葬出土的农作物有粟、黍、稻,随葬动物有鸡、猪、绵羊、黄牛、狗、马,人骨骨胶原碳稳定同位素主要呈现C3和C4混合信号,部分呈现C3信号和C4信号,氮稳定同位素值相较牛羊等家养食草动物较高。综合研究说明汉晋时期河西走廊形成麦类、粟黍和豆类的混合农业模式,所以黑水国汉代先民摄取的粮食作物来源呈多样化。同时,河西走廊畜牧业发达,使当时人群摄取了大量的肉食资源,导致蛋白质摄入量较高。

Environmental Conditions of Barchan Dune and Barchan Chain-A Case Study from the Hexi Desert Area of Gansu

[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.

甘肃省河西地区锶矿泉水富集分布规律和水质特征分析

在甘肃河西地区采集水样点231个,锶含量为0.10-2.67 mg·L^(-1),最高值达2.67 mg·L^(-1),达到饮用天然矿泉水界限含量(锶含量≥0.40 mg·L^(-1))的水样点171个,占全部水点的74.0%。按各地貌单元统计,走廊平原区含锶矿泉水点占水点总数的比例最高,走廊平原区地下水中有利于锶的富集;从地下水类型分析,第四系地下水中含锶矿泉水点数量最多,其次为地表水体,基岩矿泉水点较少;从各类型水中锶含量达到矿泉水标准的比率分析,基岩地下水锶矿泉水达标率最高,其次为第四系地下水,地表水达标率较低。依据甘肃河西地区锶矿泉水富集分布规律和水文地质特征,结合地形地貌等要素,划分出走廊平原区第四系锶矿泉水富集区和山地锶矿泉水富集区2个大区,细分了13个小区。

甘肃河西地区社火文化的地域特色及发展困境探析--以武威凉州区社火为例

甘肃河西地区的社火文化既有边塞和军旅文化的特色,又有戏曲唱腔、秧歌小调、鼓乐演奏、人物服装等多种表演形式的特点,是一门综合多种职业角色、多种民族文化、多种宗教元素、多种表演形式的民俗文化。然而,伴随着农村经济社会的发展,河西地区社火文化资源却日益枯竭,演出技艺总体上呈现出明显的衰退趋势,其种类日益减少,社火文化内涵日趋弱化,面临发展困境。社火文化是我国民间民俗传统文化艺术中不可缺少的一部分,在当前全面实施乡村振兴战略的背景下,应加强对它的研究与保护。

基于土地综合整治的河西地区实用性村庄规划路径探索——以张掖市高家庄村为例

全域土地综合整治是实施乡村振兴战略和实现乡村高质量发展的重要抓手。以甘肃省全域土地综合整治试点张掖市高家庄村为例,探讨了村庄规划“六化”对高家庄村庄总体布局、产业发展、基础设施、公共服务设施、居民点建设、用地留白等具体规划编制路径的要求,明确了基于土地综合整治的河西地区实用性村庄规划路径选择,认为土地综合整治支持河西地区实用性村庄规划具有适宜性特征,而且基于土地综合整治的实用性村庄规划就应该将土地整治任务、指标和布局要求落实到具体村庄规划实施地块上去,要重点突出“种”“养”“住”的空间谋划和项目安排。另外,河西地区具有“天时、地利、人和”的土地综合整治全域推进优势。然而,在具体村庄规划编制及实施过程中,既要“求同”,也要“存异”。基于土地综合整治“好用、管用、有用”的实用性村庄规划,就需要既能够落实上位规划的战略意图又要体现村民主体的核心意愿,从而切实为河西地区乡村振兴提供强有力的多元支持。

氮肥增效剂对春小麦产量和效益的影响

为验证氮肥增效剂在春小麦上的施用效果,以春小麦品种永良15号为指示品种,设添加不同用量的氮肥增效剂NBPT、DMPP,常规施肥和不施肥处理(对照)共5个处理,在河西灌区研究了减量施肥条件下添加肥料增效剂对春小麦生长性状、产量及经济效益的影响。结果表明,较传统施肥(N 232.5 kg/hm^(2)、P2O5241.5kg/hm^(2)、K2O 56.3 kg/hm^(2))减N 14.0%、P2O537.9%,添加脲酶抑制剂(NBPT)0.40 kg/hm^(2)、硝化抑制剂(DMPP)2.00kg/hm^(2)时春小麦主要性状表现较好,产量最高,为4693.3 kg/hm^(2),纯收益较传统施肥增加975.59元/hm^(2)。在河西灌区,春小麦在化肥减量并添加氮肥增效剂条件下能够实现节本增效,可在小麦生产中应用。

灌水量、种植密度和行距对河西地区春玉米产量的影响

为确定河西地区膜下滴灌春玉米适宜的灌水量和配套栽培技术,2020年在中国农业大学石羊河流域农业与生态节水试验站开展大田试验,设置2个灌水量(W_(1),W_(2))、2个种植密度(D_(1),D_(2))和3种行距(L1,L2,L_(3)),共12个处理,3次重复.通过测定株高、叶面积指数(LAI)、干物质累积及分配等指标,研究灌水量、种植密度与行距对春玉米生长、产量和水肥利用效率的影响.结果表明,在相同灌水量下,处理D_(2)的株高和LAI显著高于D_(1),增加种植密度提高了玉米群体干物质积累量、产量及水分利用效率(WUE).处理W_(2)D_(2)L_(3)的干物质累积量和产量最高,分别为96.45和17.72 t/hm^(2);处理W_(1)D_(2)L_(3)的水分利用效率最大,为3.57 kg/m^(3).灌水量与种植密度两者交互作用对产量及其构成因素的影响具有统计学意义(P<0.05);灌水量、种植密度与和行距三者交互作用对收获指数的影响具有统计学意义(P<0.05),对作物耗水量(ET)和WUE的影响具有统计学意义(P<0.01).灌水量、种植密度与行距均对河西地区春玉米群体结构、耗水量、产量及水分利用效率存在一定的调控效应:由大到小为种植密度、行距和灌水量.综合分析,“80%ETc+10.0万株/hm^(2)+宽窄行”为河西地区膜下滴灌春玉米适宜的灌水和种植模式.

近20a河西地区绿洲效应时空变化特征及归因分析

绿洲效应在改善干旱区气候,支持绿洲系统自我维持和发展等方面发挥着极为重要的作用。本文以甘肃省河西地区为研究区,利用气象和遥感数据,选取绿洲效应强度指标,采用地理探测器模型,揭示近20 a绿洲效应时空变化特征,分析了绿洲效应强度影响因素。结果表明:(1)2000—2020年期间,研究区绿洲效应强度在春夏冬季均呈增大趋势,秋季呈减小趋势,白天与相应季节变化相似,但强度更大,最强为夏季,增加1.43℃;夜间春夏秋季变化与相应季节相似,但强度较低,2000年秋季和2010年冬季夜间出现微弱的绿洲暖岛效应;(2)强绿洲效应(“冷岛”)面积占比在夏季最大且变化较小,而绿洲“暖岛”效应面积占比冬季最大,呈逐年减小趋势;(3)夏季绿洲效应强度与绿洲的植被覆盖变化具有强负相关性,相关系数达-0.917。气候和地表因素是河西地区绿洲效应强度的主控因素,地表反照率的影响最弱,且因子间的交互作用不容忽视。

2000—2020年河西地区生态系统服务功能时空变化与影响因素分析

河西地区是我国“三区四带”和甘肃省“四屏一廊”生态安全格局的重要组成部分,在全国生态安全战略格局中具有重要地位。利用InVEST模型、USLE方程与修正风蚀方程等评价方法,结合河西地区的气象、水文、地形、土地利用类型与土壤质地等数据,对2000—2020年河西地区的生态系统服务功能进行量化,并分析各项功能的时空变化及影响因素,识别河西地区生态系统服务功能的高、中、低值区。结果表明:2000—2020年河西地区生态系统服务功能整体向好,但波动较大,稳定性有待增强。受气候条件与土地利用格局的影响,生态系统服务功能在空间上呈现“南高北低”的分布格局。通过分析生态系统服务功能的影响因素,发现林地与草地对生态系统服务功能的提升具有关键作用,海拔在2 500~3 500 m和缓坡地区的生态系统服务功能较优。2000—2020年河西地区的生态系统服务功能综合指数呈波动上升趋势,生态系统服务功能的最优年份为2020年。生态系统服务功能的低值区主要位于河西地区西北部的平原地带,占比41%。生态修复时要减少人类活动带来的负面影响,增强区域的土壤保持与防风固沙能力。生态系统服务功能的中值区主要分布在河西地区的浅山区以及走廊绿洲,占比35%。其巩固提升对策要重点关注农牧业与环境保护协同发展的问题,对区域水资源进行优化配置,减少人地矛盾。生态系统服务功能的高值区集中在祁连山区,占比24%,是为整个河西地区提供生态资源与产品的关键区与重点区。今后要继续加强生态环境的监测与保护,维持生态系统的原真性。

明代的卫学、科举与儒家文化在河西地区的传播

洪武二十八年(1395年),随着明朝在河西地区统治秩序的确立,为巩固在河西地区的统治以及恢复汉族文化的传统,明廷便开始在河西地区大力推广儒家文化。基于学校教育对于推广儒家文化的重要作用,明朝在河西地区设置了陕西行都司学、凉州卫学、永昌卫学、肃州卫学等官学,形成了以卫学为主体的学校教育体系。虽然战争不断、地处偏远的社会环境影响了河西卫学的教学质量,但通过学校教育的培养,河西地区仍然涌现出了一批科场得意的士子和地方社会的中下层士绅,成为儒家文化和社会秩序的推广者、维护者,使得河西地区以军户为主体的卫所社区出现了明显的“文化”趋势。同时,随着儒家文化在河西地区影响力的提升,河西地区的社会风气也出现了由“尚武轻文”向“崇尚诗书”的转变。

河西灌区酿酒葡萄水肥一体化栽培技术规程

酿酒葡萄是河西地区主要优势特色产业之一。为进一步完善酿酒葡萄水肥一体化技术体系,以节水控肥、提质增效为目标,基于多年定位试验基础,采用室内野外结合、实验分析与综合调查结合等研究方法,从适用范围、规范性引用文件、术语和定义、产地气候环境条件、水肥一体化系统组成与设备安装、栽培技术、肥水管理、设施维护等方面规范了河西酿酒葡萄水肥一体化高效栽培技术。

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河西地区魏晋唐墓壁画乐器分类考略

河西地区魏晋墓和唐墓出土的壁画中描绘的乐器图像种类丰富,是甘肃音乐史学研究的重要补充。本文对壁画中所出现的各种乐器用现代乐器分类法进行分类,对这些乐器的名称及其形制、流变等进行初步的考释。

丝绸之路视域下居延遗址建筑研究

基于丝绸之路与东西方文化交流的视角,介绍了居延遗址在历史上的重要价值,分析了居延遗址的建筑形制特征及其影响,深入探讨了居延作为草原丝绸之路的重要组成部分、沟通中西亚的交通要道,在促进东西方文化交流以及助推国家繁荣上做出的巨大贡献。