Subjects: Geosciences >> Geography submitted time 2024-04-01 Cooperative journals: 《干旱区地理》
Abstract：为明确垄沟覆盖集雨模式对玉米根际土壤微生物群落结构及多样性的影响，选取“登义”2号为试验材料，采用单因素完全随机试验设计，以常规平栽不覆盖为对照（CK），依次设置垄覆普通黑色地膜沟不覆盖（HL）、垄覆液态地膜沟不覆盖（YL）、垄不覆盖沟覆秸秆（NJ）、垄覆液态地膜沟覆秸秆（YJ）、垄覆普通黑色地膜沟覆秸秆（HJ）共计6个处理，利用Illumina高通量测序技术分析土壤微生物群落构成及多样性。结果表明：（1）垄覆膜沟覆秸秆的集雨模式均有利于玉米增产、提高水分利用效率，其中HJ处理的穗行数、千粒重、产量及水分利用效率均最大，分别较对照CK提高11.22%、31.31%、88.02%、79.83%，且与CK间差异均显著（P<0.05），而垄无覆盖沟覆秸秆的NJ处理的产量及水分利用效率均较CK低。（2）垄覆地膜各处理均能显著提高微生物群落多样性，且能改变微生物结构，但垄无覆盖沟覆秸秆的NJ处理却不能。（3）各处理的微生物群落组成在门、纲水平上均受到覆盖集雨模式的影响。土壤微生物群落中主要优势菌门为变形菌门（Proteobacteria）、酸杆菌门（Acidobacteria）、芽单胞菌门（Gemmatimonadetes）和拟杆菌门（Bacteroidetes）；主要优势菌纲为γ-变形菌纲（Gammaproteobacteria，占比25.8%）、拟杆菌纲（Bacteroidia，占比8.4%）和α-变形菌纲（Alphaproteobacteria，占比7.7%），且垄沟覆盖有助于提高土壤微生物丰富度、多样性和均匀度指数，即垄沟集雨模式可通过改变土壤微生物门、纲水平的结构及组成，实现玉米增产的效果。
Subjects: Geosciences >> Geography submitted time 2024-03-15 Cooperative journals: 《干旱区地理》
Abstract：蒸散发过程影响因素众多，潜在蒸散发（ET0）与气象变量交互作用复杂，亟需揭示ET0变化对气象变量的响应机理。基于河西走廊及周边21个气象站点气象资料，采用定性定量分析方法，以河西走廊整体及3分区2个空间尺度，揭示ET0时空变化规律，明确ET0对各气象因素变化敏感性及贡献。结果表明：（1） 河西走廊及分区ET0均呈显著波动上升趋势（Z>1.98），线性变化率2.94 mm·a-1，且黑河分区变化最明显。（2） ET0由东南向西北递增变化，中东部石羊河分区（1003.78 mm）、黑河分区（1031.30 mm）较小，西部疏勒河分区（1171.89 mm）较大。（3） 河西走廊ET0对气象因素变化敏感性排序为相对湿度（RH）、日最高气温（Tmax）、日照时数（n）、平均风速（u）、日降水量（P），ET0对RH减少最敏感，对P变化最不敏感。（4） u增大是造成河西走廊ET0增大的主要原因，其次是RH减少、Tmax升高、n增加。（5） 疏勒河分区、黑河分区、石羊河分区ET0呈增加变化，贡献最大因素分别为Tmax（5.13%）、u（8.22%）、Tmax（5.97%），贡献最小因素为n。气候因素中的风速和气温变化是河西走廊地区ET0变化不容忽视的重要影响因素，研究成果对合理规划农田灌溉用水和提高农业水资源利用效率意义重大。
Subjects: Geosciences >> Hydrology submitted time 2022-12-20 Cooperative journals: 《干旱区研究》
Abstract：
A quantitative analysis of runoff variation characteristics is the basis for finding out its impact mechanism, and it is also an important basis for accurately evaluating water resources. This study used eight annual distribution indexes, such as the Gini coefficient and Lorentz asymmetry coefficient, combined with the M-K test、R/S analysis, and other mathematical statistics methods, to comprehensively analyze the process of the runoff of the upper reaches of the Shule River from the annual and interannual levels. The results showed that the following: (1) during the year, a unimodal distribution was shown, which was mainly concentrated in the flood season concentration degree (D), inhomogeneous coefficient (Cv), Gini coefficient (GI), relative change range (Cm) decreased respectively at the rate of - 1.053 · (10a)- 1 , - 0.015 · (10a)- 1 , - 0.009 · (10a)- 1 ,- 0.643 · (10a)- 1 , complete adjustment coefficient (Cr), Lorentz asymmetry coefficient (S), concentration period (Cn) all decreased at the rate of -0.006·(10a)-1 . The distribution tended to be uniform gradually according to the changing trend of its characteristic index during the year. (2) The annual runoff showed an overall increasing trend, but an abrupt change occurred in 1997, and the average annual runoff afterward increased by 59% compared before the change. (3) The runoff generally showed an upward trend in all four seasons, among which the trend rate was the greatest in the summer and the smallest in the winter. After the abrupt change in the 1990s, the average runoff increased significantly compared to before the abrupt change, and the change range was in the following order: autumn (76%) > winter (74%) > summer (58%) > spring (45%). (4) The annual and seasonal runoff in the upper reaches of the Shule River had multiple time characteristic scale periods, and the first major cycle were both 56 years. (5) According to the predicted runoff from 2022 to 2024, it was found that the runoff of the upper reaches of the Shule River will continue to increase in the next three years. These results provided a scientific basis for accurately grasping the runoff variation laws and characteristics of the upper reaches of the Shule River and had certain guiding significance for the sustainable development and utilization of water resources in the Shule River Basin and the study of the runoff variation laws in inland river basins.
Subjects: Geosciences >> Hydrology submitted time 2022-12-20 Cooperative journals: 《干旱区研究》
Abstract：
The water ecological security evaluation index system was constructed based on the complex ecosystem (social-economic-compound ecological system and pressure-state-response model) concept. From 2009 to 2018, the statistical data of Shiyang River Basin were used. The fuzzy system analysis method and BP neural network model were used to analyze the many aspects of the driving mechanism of water ecological security in the Shiyang River Basin. The results showed that the precipitation change, livestock, ratio of ecological environment water consumption per unit area to total water use, rainwater utilization, and diameter fouling were the main influencing factors of water ecological security in the river basin during the study period. From the WSENCE system view, the current influence degree of water ecological security were ranked as follows: resources subsystem≥social subsystem>economic subsystem>environment subsystem>ecological subsystem; from the PSR system view: response subsystem>pressure subsystem>status subsystem; the resources and pressure subsystems were the main driving force of water ecological security from 2009 to 2018. The pressure and environment subsystems were the main driving force of water ecological security from 2019 to 2023. In the last ten years, water ecological security of the Shiyang River Basin was still in the levelⅠarea (poor) and levelⅡ area (in general). Overall, the situation was poor
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-11-19 Cooperative journals: 《干旱区地理》
Abstract：基于甘肃省清水县汤峪河径流小区2015—2017年的观测数据，研究不同植被恢复模式条件 下坡面次降雨入渗、产流产沙特征。结果表明：不同植被恢复模式条件下的土壤入渗量与降雨强度呈二次函数关系，存在入渗量达到最大值的临界降雨强度。入渗速率与降雨历时可以用幂函数关系表达，符合考斯恰可夫入渗模型。不同植被恢复模式条件下的产流率在0.003 3～0.003 6 mm·min-1之间，相对裸地的减流率为54%～58%。产流率与降雨强度之间呈二次函数关系（R2＞0.88），产流率的主要影响因素是降雨强度。径流含沙量平均值乔灌混合区（3.13 g·L-1）＞灌木林（2.95 g·L-1）＞乔木林（2.79 g·L-1）＞草地（2.58 g·L-1），径流含沙量与降雨强度呈线性递增函数关系。裸地的产沙量显著高于各植被小区（P＜0.05），是各植被小区的43～57倍，各植被小区的减沙率在93%～94%之间，减沙效益高于其减流效益。各植被坡面土壤流失量与降雨侵蚀力呈线性递增函数关系；产流率与侵蚀产沙率之间呈极显著正相关关系（P＜0.01），二者间可采用二次函数关系表达。本研究成果可为黄土高原丘陵沟壑区水土保持优化配置提供理论依据。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-04-26 Cooperative journals: 《干旱区研究》
Abstract：选取疏勒河干流3个水文站1956—2016年逐月、逐年降水数据作为基础资料，采用线性倾向、累积距平、滑动平均、MannKendall突变检验等方法，分析疏勒河干流降水量年变化、年内变化、年代际变化、季节变化和突变特征。结果表明：疏勒河干流年降水量呈现不同程度增加趋势，年降水量倾向率排序表现为：昌马堡站5.47 mm·（10a）-1>双塔堡水库站1.454 mm·（10a）-1>潘家庄站0.866 mm·（10a）-1；降水量年内分配极不均匀，主要集中于5—8月，占年降水量的65%以上；降水量年代际呈现20世纪60年代和90年代降水量均低于多年平均值，20世纪70年代和21世纪10年代降水量均高于多年平均值；降水量季节变化不同站点呈现不同变化特征，昌马堡站、潘家庄站和双塔堡水库站分别是夏季、秋季和秋季降水对降水量贡献最大，同时不同季节不同年代平均降水量距平呈现不同变化特征；降水量突变年在不同季节呈现不同突变特征和不同突变时间，昌马堡站、潘家庄站和双塔堡水库站年平均降水量突变点分别为1964年和2001年、1988年和1987年。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-10 Cooperative journals: 《干旱区研究》
Abstract： 紫花苜蓿是我国重要的豆科牧草，具有较强的抗旱能力，而水分亏缺是影响其产量的主要逆境因子之一。通过大田试验对不同水分胁迫下紫花苜蓿的光合特性及产量进行研究，结果表明：① 土壤水分胁迫对紫花苜蓿光响应参数影响显著(P＜0.05)，随着水分胁迫的加剧，最大净光合速率、表观量子效率、光饱和点逐渐降低，暗呼吸速率、光补偿点逐渐升高，从而直接影响紫花苜蓿光合作用对弱光的吸收和转化效率。② 随着水分胁迫的加剧紫花苜蓿叶片的净光合速率(Pn)和蒸腾速率(Tr)呈显著的下降趋势，气孔导度(Gs)呈先下降后上升的趋势，表明轻度水分胁迫下气孔因素是Pn下降的主要因素，中度和重度水分胁迫下非气孔因素是Pn降低的主要因素。③ 当光合有效辐射(PAR)为1 200 μmol·m-2·s-1时，轻度水分胁迫的水分利用效率(WUE)显著大于充分灌溉的WUE (P<0.05)，表明适度水分胁迫可提高紫花苜蓿叶片的水分利用效率。④ 轻度水分胁迫与充分灌溉干草产量之间无显著差异，表明轻度水分胁迫能达到高产节水的目的。
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