Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：以呼和浩特市武川县不同农田和天然草地为研究对象，采用野外原位监测和室内试验结合的方法，对典 型小麦留茬地、葵花留茬地、翻耕地、退耕地4种农田土壤进行研究，并通过分析平均粒径、标准差、偏度、峰度，对不 同利用方式下土地抗风蚀能力进行探讨。研究结果表明：（1）研究区土壤以细砂、极细砂和粉粒为主，占比达80%~ 85%。（2）土壤粒度组成由细到粗为：翻耕1 a＞天然草地＞翻耕边坡＞小麦留茬＞翻耕15 a＞退耕5 a＞葵花留茬， 沙粒平均粒径为2.12~2.61。（3）各层土壤分选性较差，偏度均表现为正偏且近于对称，峰度属于宽平态。土壤易风 蚀颗粒粒径范围在200~400 m。（4）与天然草地相比，农田垦殖利用导致土壤粒径分布范围扩大，粒径整体趋于粗 粒化。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：为探究河西灌溉区农田生态系统土壤养分限制及其循环规律，明确不同水分处理下青贮玉米植株与土壤 的稳态性特征，以甘肃省河西灌溉区W（0 传统灌水）、W（1 节水10%）、W（2 节水20%）、W（3 节水30%）4种灌水处理的 青贮玉米为研究对象，分析不同灌水处理下土壤、植株有机碳（OC, Organic Carbon）、全氮（TN, Total Nitrogen）、全磷 （TP, Total Phosphorus）含量及其生态化学计量特征变化和植株与土壤间的内稳性特征。结果表明：（1）不同灌水处 理下青贮玉米土壤OC、TN、TP含量均在0~10 cm土层达到最高值。（2）4种灌水处理下，植株器官养分含量在W0灌 水处理下显著升高；在0~30 cm土层土壤OC、TN、TP含量在W1灌水处理下最高，且TN、TP显著高于其余灌水处理 6.66%~26.17%、4.67%~19.21%；随灌水量减少土壤及植株养分降低显著。（3）土壤、植株C∶N、C∶P、N∶P值变化范围 分别为 3.60~61.2、4.39~53.9、1.01~1.24，其中，土壤 C∶N 值在各土层及不同灌水处理下较为稳定，叶片（11.9）、根 （7.58）的N∶P值均小于植株氮限制的阈值（14），说明植株生长受到氮元素的限制。（4）4种灌水处理下，植株（根、叶 片）OC、TP元素及其化学比值稳态性均呈现绝对稳定状态，但在W2处理下叶片N∶P稳态性表现出敏感状态。可见， 在河西灌溉区，节水10%不仅有利于青贮玉米土壤养分的存留及保持作物生长的稳定适应能力，也可达到节水目 的，进而缓解水资源紧缺的现状。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Studying the spatial and temporal variations of the net carbon sink function of oasis farmland is important for its management and sustainable development. The net carbon sink of Aksu oasis farmland was estimated on the basis of remote sensing, meteorological data and agricultural inputs, and other related statistics from 2001 to 2017. The following results are presented. (1) In the past 17 years, the net ecosystem productivity (NEP) of oasis farmland in Aksu showed an increasing trend yearly, with an average annual growth rate of 7.43%. Among which, the area of oasis farmland with a significant increasing trend of NEP was 1.44 × 104 km2 , accounting for 97.7% of its total area, which is mainly distributed in various counties and cities. The area with a significant decreasing trend was 339 km2 , accounting for 2.3% of the total area, mainly in the oasis areas of Wensu, Awati, Aksu, and Kuche counties. (2) Carbon emissions from agricultural production inputs increased from 39.94 × 104 t in 2001 to 106.73 × 104 t in 2017, with an average annual growth rate of 25.14% and high and low distribution patterns in the Southeast and Northwest, respectively, considering spatial distribution. The largest proportions of agricultural production input pathways are fertilizer and agricultural machinery at 28% and 26%, respectively. (3) From 2001 to 2017, the net carbon sink of Aksu oasis farmland showed a fluctuating upward trend, spatially demonstrating a gradual increase from Northwest to Southeast, with high values mainly distributed in the southwestern part of Wensu county, the western part of Aksu City, the entire territory of Alar City, and the eastern part of Xinhe County. Overall, Aksu oasis farmland has a high net carbon sink capacity. However, regional differences are found in the net carbon sinks of oasis farmland among counties and cities. Thus, the net carbon sink capacity of oasis farmland should be improved by optimizing the agricultural industry structure and enhancing farming measures.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Soil salinity aggregation will change soil acidity or alkalinity. As an important land resource reserve area in China, soil salinization and secondary salinization problems are frequent in Xinjiang, Therefore, accurately obtaining soil salinity information and effectively improving soil salinity is beneficial to regulating the contradiction between agricultural irrigation and freshwater resources. Such regulation is of considerable important to the sustainable development of agricultural production and ecological environment. In this study, the soil pH value of cotton fields in Alar Reclamation Area, southern Xinjiang, was taken as the research object, and the EM38-MK2 geodetic conductivity meter was used on the basis of electromagnetic induction technology to obtain soil apparent conductivity data of nine cotton fields in the Reclamation Area. In each cotton field, soil apparent conductivity thresholds were collected in accordance with cotton fields of 0- 0.375, 0.375- 0.75, 0.75- 1.00 m depth, 54 profile samples were collected from three soil layers, and 486 soil profile samples were collected from nine cotton fields. The linear regression model between soil pH and soil apparent conductivity was constructed using two ideas of the global and different regions and combined with geostatistical software to quantify in cotton fields in the Reclamation Area. The two-tailed test results revealed that the correlation coefficients between apparent conductivity and soil pH were 0.60-0.95 for the idea of different regions under the condition of P < 0.01; while those for the global regions were 0.28-0.46. Both findings were highly significant negative correlations, indicating that EM38- MK2 could be used for the determination of soil pH. Linear regression models between apparent conductivity data and soil pH were constructed using the global region and different regions. The zonal models 0.74 ≤ R2 ≤ 0.93 and 2.00 ≤ RPD ≤ 3.50, which have smaller RMSE, showed high accuracy, indicating that the accuracy of the different region model is better than that of the global region models. Meanwhile, the accuracy of the soil pH inversion model is also higher in areas with higher salinity. The Kriging interpolation results showed that the soil pH in the deep layer of cotton fields in the Reclamation Area was higher than that in the surface layer due to the influence of winter irrigation, cotton root system and cotton dead leaves. This study aims to provide ideas for the rapid determination of soil pH. Therefore, soil acid- base risk prediction can be accurate, and effective risk countermeasures can be formulated rationally
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： This article takes the farmland soils in the Syr Darya River Basin of Kazakhstan as the research object, combining classical statistics and geostatistics methods, and investigates the characteristics of soil grain size and spatial heterogeneity in the 0-20 cm soil layer. Results showed that the distribution characteristics of soil particles with different particle sizes in each study area were similar, and the average content of particles with particle sizes of 0.25-0.05 mm and 0.05-0.01 mm is the highest. Except for subzone 3, the content of soil particles with a particle size of 1.0-0.25 mm has strong variability, while that of other sizes has a moderate degree of variability; Except for soil particles with a particle size of 1.0-0.05 mm in subzone 1, the nugget coefficient of soil particle content of other particle sizes is all < 40%, and that of each particle size in subzone 2 is all < 50%, in subzone 3, except for soil particles with a particle size of < 0.001 mm, the nugget coefficient of soil particle content of other particle sizes is < 40%. These findings revealed that the composition of soil particles in each study area has been affected by varying degrees of random factors; The Kriging interpolation method was used to interpolate the content of soil particles of different sizes in the study area. The interpolation results showed that the content of soil particles of different sizes in the study area demonstrated different distribution characteristics in the spatial distribution. The research results can provide a scientific basis for the rational use of farmland soil and the improvement of degraded soil.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Typical urban rivers in Xi’an (Ba River, Chan River, Feng River, and Hei River) were selected as the research object to understand the impact of different land-use types on the distribution of heavy metals in river sediments. The spatial distribution, environmental risks, and sources of heavy metals (Cr, Mn, Ni, Cu, Zn, Cd, and As) in river sediments were analyzed and evaluated using potential ecological risk (RI), pollution load index (PLI), correlation analysis, and principal component analysis. Results showed that the content of heavy metals in the sediments of the four rivers was presented in the following order: Chan River > Ba River > Hei River > Feng River. The RI results showed that Cd remarkably contributed to the pollution, and the four rivers were all at moderate potential ecological risk. The PLI results showed that the H1 sample site in Hei River was moderately polluted, which was the highest. The RI and PLI results showed that the sample sites in the Chan River were the most polluted, and they were concentrated in the middle and lower reaches where the proportion of artificial ground and intensity of human activities were high. In addition, the results of correlation analysis and principal component analysis showed that most heavy metals came from human activities such as emissions from industrial and agricultural production and traffic pollution. Therefore, attention should be paid to the prevention and control of Cd pollution, particularly in the middle reaches of Feng River and Hei River, to prevent further pollution.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Research on landscape spatiotemporal variation and its pattern vulnerability can provide a scientific basis for regional landscape optimization and ecological protection. Based on six periods of landscape type data from 1980 to 2020, this paper analyzes the lake basin landscape and its variation process in Liangcheng County. Moreover, a comprehensive evaluation index of landscape vulnerability is constructed by using landscape sensitivity and adaptability indexes to analyze the spatiotemporal differentiation characteristics and influencing factors of landscape pattern vulnerability in the entire county. The main findings are listed below. (1) The landscape types of Liangcheng County have significantly changed over the past 40 years. Except for the unused land, the dynamic degree of cultivated land, forestland, and grassland from 1980 to 1995, that of each landscape type from 1995 to 2010, and that of waters and construction land from 2010 to 2020 are the largest, which indirectly reflects the life and production modes of the study area in different periods. (2) The landscape pattern vulnerability was mainly medium and high- grade with an area of more than 70% in Liangcheng Country from 1980 to 2020. The areas of high landscape pattern vulnerability were mainly concentrated in the central and southeast of Liangcheng, and the low-value areas were located in the Daihai and its northern parts. The landscape vulnerability integrated index generally decreased first; this index then increased and finally decreased. Moreover, the spatial aggregation increased, indicating that the ecological environment began to improve. (3) The vulnerability of ecological environments is significantly different in various landscape types and topographies in the study area. Forestland and grassland have more higher vulnerability and water has the lowest vulnerability among all landscape types. The landscape pattern vulnerability is the lowest in the area with an altitude of <1300 m and a slope of <5° and the highest with an altitude of 1700-1900 m and a slope of 25°-40° on different altitudes and slopes. (4) The gray correlation analysis revealed that the population, water area, and farmland area are the leading factors that affected the landscape pattern vulnerability, indicating that human activities significantly impacted the ecological environment more than climatic factors in the study area. Optimizing landscape structure, reducing excessive disturbance, and protecting water resources and their environment are the primary ways to reduce the vulnerability of landscape patterns and ecological protection in Liangcheng Country.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： A quantity-space coupling model can effectively simulate the number of land-use patches and their rapid spatial changes. Thus, this model has become the main method of land use research in recent years. This research first compared the simulated land-use structure of the patch-generating land-use simulation model (PLUS), future land-use simulation model (FLUS), and conversion of land use and its effects at small regional extent (CLUE-S) in the Gan-Lin-Gao region (Ganzhou District, Linze County and Gaotai County of Zhangye City) of the middle reaches of the Heihe River Basin in 2015. In addition, this research selected the suitable spatial simulation model for the study area; then, it was coupled with the system dynamics model (SD) to form a quantitative-spatial coupling model. Finally, the coupling model was used to predict the land-use structure of the economic development (ED), ecological protection (EP), and harmonious development (HD) scenarios, and comparative evaluation was conducted. The research results showed that (1) at the same pixel scale, the figure of merit of the PLUS model was higher than that of the FLUS and CLUE-S models, and the Kno and Klocation of the three models were PLUS, CLUE-S, and FLUS from high to low, indicating that the PLUS model had the best spatial fitting effect in this study area. (2) Moreover, the different scenarios predicted by the PLUS- SD coupling model showed that the construction land and arable land in the ED scenario expanded rapidly, but the forest coverage rate was low. Furthermore, the forest coverage rate in the EP scenario increased significantly, but the level of ED was low, and the urbanization in the HD scenario improved when the ecological environment was gradually developing. This research determined the significant advantages of the PLUS- SD coupling model and highlighted the effective land-use spatial simulation capabilities of the PLUS model and powerful data processing capabilities of the SD model. The results can provide reference for the formulation of land planning policies.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Based on the data of 107 counties and regions in Shanxi Province in 2000, 2005, 2010, and 2018, this paper constructs the evaluation index system of high-quality development in Shanxi Province, uses the InVEST model to calculate the ecosystem services of counties and regions in Shanxi Province, and analyzes the spatiotemporal coupling characteristics of the high-quality development system and ecosystem services of counties in Shanxi Province by using the coupling coordination model and elasticity coefficient method. The following results are presented. (1) The grade effect of cities has a significant impact on the level of high-quality development. The spatial differentiation law of high-quality development is strong, which roughly forms the north-south-middle three- level cores, and the polarization effect in the central region is prominent. (2) Ecosystem services in the study area have locking effects in time scale and spatial pattern. The temporal and spatial evolution characteristics are consistent with the topographic distribution of the study area, showing a stable“mirror L- shaped”spatial distribution pattern. (3) Ecosystem services in the study area generally lag behind high- quality development. From the perspective of the time change, the coupling level shows an upward trend. From the perspective of spatial pattern characteristics, ecosystem services and the high-quality development show the coordination main axis of“northeast-southwest.”(4) The coupling type of high-quality development and ecosystem services in the study area mainly changes in different directions, generally showing a retrogressive development trend. A “polarization”pattern, in which recession and lag types compete, is also observed, forming a convergent“S” type attenuation area. As an ideal model of coupling type, growth type is remarkably few in the study area.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract： Revealing the relationship characteristics between the intensity of ecosystem service (ES) tradeoffs and the matching degree of ES supply and demand can provide possible ways to alleviate the ES conflict and supply- demand contradiction simultaneously. The districts and counties of Shanxi Province are selected in this study. Considering the tradeoff between supply and support service, tradeoff type 1 is when the supply service is relatively enhanced but support service is decreased, whereas tradeoff type 2 is the opposite condition. The influencing factors of ES tradeoffs and supply-demand and their related characteristics are revealed by redundancy analysis and piecewise linear regression. The following results are presented. (1) The high- value regions of tradeoff type 1 and the low-value regions of supply-demand ratio are mainly located in the basins, and the highvalue regions of tradeoff type 2 and supply-demand ratio are mainly located in the mountainous area. (2) Tradeoff type 1 is mainly affected by cropland, forestland, grassland, air temperature, and other factors. Meanwhile, tradeoff type 2 is primarily influenced by cropland, forestland, NDVI, and soil organic matter, but the direction of effects is opposite to that of tradeoff type 1. (3) The forestland, grassland, and slope gradient have significant positive effects on the supply-demand ratio of type 1, while the cropland and construction land have significant negative effects. The factors have minimal effects on the supply-demand ratio of type 2. (4) The effects of factor direction on tradeoff type 1 and the supply-demand ratio are opposite, which mainly contributes to the negative correlation between them. The response of the ES supply-demand ratio to tradeoffs is relatively strong when the contradiction between ES supply and demand is small. However, this response weakens with the deepening of the supply-demand contradiction. The relationship characteristics indicate the ecological dilemma: the human demand increases-development intensity increases-tradeoff type 1 enhances-the contradiction between supply and demand intensifies. A weak positive correlation is observed between tradeoff type 2 and supply-demand ratio, indicating the situation of ecological surplus. Overall, a correlation is observed between ES tradeoff and supply- demand. The results generally present the correlation characteristics and its formation mechanism, which can provide a scientific basis for land ecological restoration and management.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：为阐明高寒草地啮齿类动物活动区鼠丘土壤风蚀特征和规律，以青海省河南县鼠害退化区高原鼠兔和高 原鼢鼠鼠丘为研究对象，采用野外模拟风力侵蚀试验方法，对2类鼠丘土壤风蚀流失量和养分流失量的特征和规律 进行研究，并对该2种鼠丘土壤风蚀差异进行对比和分析。结果表明：（1）在9 ms-1 的恒风速吹蚀作用下，2种鼠丘 土壤颗粒的快速流失主要集中在前15 min内，且高原鼠兔鼠丘土壤流失量显著高于高原鼢鼠鼠丘，约为高原鼢鼠 鼠丘土壤流失量的1.5倍。（2）蠕移是鼠丘土壤流失最主要的运动方式，相同时间内2种鼠丘均呈现蠕移量>跃移 量>悬移量，其中高原鼠兔鼠丘蠕移量、跃移量和悬移量分别为高原鼢鼠鼠丘的1.45倍、1.58倍、1.50倍。（3）鼠丘土 壤养分含量明显低于原生草地土壤层，且养分含量呈现出原生草地土壤>高原鼠兔鼠丘土壤>高原鼢鼠鼠丘土壤。 （4）鼠丘土壤养分流失和土壤流失具有相同的规律，养分流失主要取决于土壤颗粒的流失，高原鼠兔鼠丘的各养分 含量指标的流失量较高原鼢鼠鼠丘增加1.42~3.53倍。研究结果将为阐述鼠害退化区土壤流失特征，揭示高寒草地 退化机理和黄河源草地生态环境保护提供理论依据。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：蒙古国风蚀沙漠化严重，成为世界主要的沙尘源地之一，为了深入了解蒙古国全域风蚀时空变化特征，利 用蒙古国境内的GLDAS、OLM、MOD13Q1、NASA-SRTM等气象和遥感数据，基于GEE（Google Earth Engine）云计算 平台，利用RWEQ模型计算了蒙古国土壤风蚀量和时空变化规律，分析了土壤风蚀的主要影响因素及作用机制。 结果表明：（1）自20012020年，蒙古国土壤风蚀呈北部低、南部高的空间分布格局；土壤风蚀主要发生在春季，风 蚀量占全年的45%；近20 a土壤风蚀量总体上呈显著增加趋势，风蚀模数以0.06 thm-2a-1 的速度增长。（2）蒙古国 土壤风蚀变化整体上与气候因子及由其引起的植被盖度变化有关，与放牧、耕地开垦等人为活动增强有密切关 系。研究结果可为蒙古国风蚀沙漠化防治提供重要的科学参考。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：为探究不同降雨频率对甘南尕海湿草甸土壤铵态氮（NH+4 -N）、硝态氮（NO-3 -N）、全氮（TN）的影响，于 2019年植物生长季（510月），通过模拟极端降雨（25 mm灌溉量）设置5种不同降雨频率处理：CK只接收自然降 雨，DF1每周浇灌1次（19次25mm），DF2每2周浇灌1次（9次25 mm），DF3每3周浇灌1次（6次25 mm），DF4每4 周浇灌1次（4次25 mm）；所有处理均接收自然降雨。结果表明：不同降雨频率处理对尕海湿草甸土壤氮组分有显 著影响（P<0.05）。降雨频率的增加提高了510月土壤 NH+4 -N和 NO-3 -N含量，NH+4 -N和 NO-3 -N的峰值有显著 升高，两者的峰值并未提前出现；与CK相比，降雨频率的增加提高了土壤 NH+4 -N和 NO-3 -N含量，降低了TN含量； 而在不同降雨频率间，随降雨频率的梯度增加，0~40 cm土层 NH+4 -N和 NO-3 -N均呈先增后减的趋势，TN呈先减后 增的趋势；不同降雨频率处理下，各土层NH4+ -N的TN占比均高于 NO-3 -N，且土壤 NH+4 -N、NO-3 -N、TN含量均随土 层深度增加而降低。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：探究土壤酶活性对UV-B辐射和不同凋落物分解的响应对揭示凋落物周转及土壤养分动态具有重要意 义。采用模拟UV-B辐射滤减（聚脂薄膜法）和分解袋法，研究了UV-B辐射变化对西北干旱荒漠区典型灌丛红砂和 珍珠以及二者的混合凋落物层下土壤酶活性的影响。结果表明：（1）辐射滤减提高了不同凋落物土壤脲酶和碱性 磷酸酶活性，且对珍珠灌丛土壤酶活性的促进作用更明显，不同土层（0~5 cm 和 5~15 cm）分别增加了 45.45%、 58.28%和39.04%、117.65%；然而，辐射滤减降低了不同凋落物土壤多酚氧化酶和木质素过氧化物酶活性，同样对珍 珠灌丛土壤酶活性的抑制效应更明显，不同土层分别减少了36.69%、39.52%和59.78%、43.63%；辐射滤减对土壤纤 维素酶活性无明显效应。（2）在辐射滤减和自然光照条件下，混合凋落物土壤多酚氧化酶活性均小于单一凋落物， 说明混合凋落物土壤中有机质的腐殖化程度大于有机质的积累，土壤腐殖化程度更高。（3）不同类型凋落物对表层 土壤（0~5 cm）酶活性的影响更为明显；随着土层加深，各类型下土壤脲酶和磷酸酶活性均降低，多酚氧化酶活性增加。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：土壤水分特征曲线是土壤的重要水分运动参数之一，受土壤质地、容重、结构、温度等影响。为探明初始 容重对土壤水分特征曲线及相应水分运动参数的影响，选取3种类型土壤，分别设置5个初始容重处理，利用van Genuchten模型拟合获取土壤水分特征曲线及其水分运动参数，分析初始容重对不同类型土壤水分特征曲线及相 应水分运动参数的影响。结果表明：（1）近饱和段（SS>100 kPa），黑土的水分特征曲面随 着初始容重的增加平缓上升，红壤的水分特征曲面在初始容重由1.3 cm3cm-3 增加到1.4 cm3cm-3 的过程中呈下降 趋势，塿土的水分特征曲面在初始容重由1.3 cm3cm-3 增加到1.4 cm3cm-3 时上升的更加陡直。（2）van Genuchten模 型对土壤水分特征曲线拟合效果较好（R2>0.99），适用于这3种类型土壤不同初始容重条件下的水分特征曲线的拟 合。（3）3种土壤的水分运动参数、s与初始容重均表现为显著的负相关关系（P在不 同初始容重间差异显著（Pr与初始容重表现为显著的负相关关系（Pn表现为显著的正相关关系（Pn呈负相关关系，但关系不显著（P>0.01），且3种土壤不同初始容重处理间水分运动参数n的变化幅度 较小，变化幅度维持在0.1左右。研究结果可为不同类型土壤、不同初始容重条件下土壤水分运动参数的获取及水 文过程模拟提供参考。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：通过室内放水冲刷试验，对4种覆沙条件和3种径流坡长条件下的产流产沙过程及水沙关系特征进行了 研究。结果表明：覆沙坡面的初始产流时间相比于黄土坡面明显延长，初始产流时间随着覆沙厚度的增加而增大， 且产流量和产沙量峰值出现的时间存在不同步性。不同坡面的产流率在试验初期较小，随着产流历时的延长逐渐 增大并且趋于稳定。黄土坡面的产沙率随产流历时的延长变化趋势较为平稳，覆沙坡面的产沙率波动范围较大。 不同坡面的累积产沙量均随着累积产流量的增加而逐渐增大，并且两者之间呈幂函数关系。由于沙层具有一定的 蓄水功能，导致覆沙坡面的侵蚀过程明显不同于黄土坡面，覆沙厚度是影响坡面侵蚀特征的重要因子，该研究为进 一步揭示复合坡面的侵蚀特征提供科学依据。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：选择草地类型丰富多样的北疆作为研究区。基于MODIS NDVI数据，获取时间累积归一化植被指数TI#2;NDVI和年最大NDVI(NDVImax)，借助GIS空间分析技术、变异系数（CV）及Mann-Kendall非参数趋势检验等方法，对 20002019年北疆地区草地覆盖动态变化进行了分析，并探究了TI-NDVI和NDVImax对草地时空异质性的表达能 力的比较优势。结果表明：（1）用NDVImax和TI-NDVI表征的北疆草地呈现明显海拔分异。TI-NDVI总体随NDVI⁃ max的增大而增大，但NDVImax或TI-NDVI相同的区域，其TI-NDVI或NDVImax却存在较大差异。（2）20002019 年北疆地区草地TI-NDVI和NDVImax总体呈显著增加趋势（PCV 均高于NDVImax。TI-NDVI对高覆盖草地的时空异质性反映更敏感，能在一定程度上削弱草地动态评价中NDVI光 饱和缺陷的影响。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：利用TDP插针式植物茎流计，对青土湖510月不同直径梭梭茎干液流通量（SV）日、季变化进行监测，结 合气象数据，研究青土湖梭梭的耗水特性及其对环境因子的响应特征。结果显示：（1）晴天，68月梭梭SV日变化 曲线主要呈单峰型；7月偶有多峰型，峰值出现较早；910月梭梭SV明显降低，日变化中峰值时间推迟。雨天，梭 梭SV呈多峰型且明显低于晴天。（2）梭梭SV在5月达到最大值，610月梭梭SV呈先增后降趋势。（3）梭梭510 月日均耗水量2.15~5.28 kgd-1，接近古尔班通古特沙漠原生梭梭59月日均耗水量2.8~6.4 kgd-1 。（4）日尺度下梭 梭SV与气象因子的相关关系依次为：净辐射>气温>饱和水汽压差>相对湿度>风速。（5）晴天土壤水分与梭梭SV呈 极显著相关，且在土层100 cm以下的根区是影响梭梭SV的主要区域。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：为巩固塔里木河下游输水成效，需要采用适宜的灌溉方式并结合断根萌蘖技术，促进胡杨林的更新复壮 及下游的生态修复。以往的研究很少将不同灌溉模式与断根萌蘖生态修复效果相结合。因此，根据地形特点将研 究区分为A1、A2、A3分区，对研究区开沟断根后，根据灌溉间隔、时长、水量的不同设置4种灌溉模式，具体为对照组 （未进行灌溉的自然条件, F1）；灌溉间隔11 d，每10 m断根沟的灌溉水量为6 m3，灌溉持续时长2 d（F2）；灌溉间隔23 d，每10 m断根沟的灌溉水量为7 m3，灌溉持续时长3 d（F3）；灌溉间隔33 d，每10 m断根沟的灌溉水量为8 m3，灌溉 持续时长4 d（F4），调查在不同的灌溉处理下胡杨萌蘖更新情况。结果表明：（1）远端根萌蘖能力优于近端根，A1、 A2、A3分区内远端根的萌芽率分别为70.7%、77.1%、64.1%；胡杨萌蘖点距萌蘖根切面的距离集中在1~16 cm；萌蘖点 与母树距离集中在5.5~7 m；萌蘖根分布深度集中在30~50 cm；萌蘖根直径集中在0.4~0.7 cm。（2）根据胡杨根蘖苗 的萌发数量，确定了适宜胡杨根萌蘖的土壤温度以及含水率区间分别为26.5~28.1 ℃、10.6%~13.1%；适宜胡杨根蘖 的灌溉模式为灌溉间隔23 d，每10 m断根沟的灌溉水量为7 m3，灌溉时长3 d（F3）。研究结果可为塔里木河流域胡杨林更新复壮提供参考
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2022-09-26 Cooperative journals: 《干旱区研究》
Abstract：灌木、半灌木和小乔木是干旱荒漠区主要的植物类型，这些荒漠植物在维持荒漠区生物多样性和生态功 能方面起着重要的作用。利用高通量测序技术，分析了阴山北麓荒漠区6种典型荒漠植物群落：红砂（Reaumuria songarica）、白刺（Nitraria tangutorum）、沙冬青（Ammopiptanthus mongolicus）、蒙古短舌菊（Brachanthemum mongoli⁃ cum）、盐爪爪（Kalidium foliatum）和梭梭（Haloxylon ammodendron）的土壤细菌多样性和群落组成及其与土壤因子的 关系。结果表明：（1）6种荒漠植物群落土壤理化性质差异显著，其中盐爪爪和红砂群落土壤水分和养分条件较好； （2）土壤细菌优势类群均为放线菌门（Actinobacteria）和变形菌门（Proteobacteria），两者占细菌总数的60%以上，优 势细菌门所占比例在6种植物群落之间差异显著；（3）盐爪爪群落土壤特异性细菌物种数显著高于其他植物群落， 盐爪爪与红砂群落的土壤细菌Shannon多样性指数显著高于其他植物群落，Shannon多样性指数对环境变化的响应 更为敏感，土壤水分和养分越高，细菌Shannon指数越高；（4）冗余分析（RDA）结果表明：不同植物群落引起的土壤 含水量、机械组成、pH和电导率的变化驱动了土壤细菌群落组成。
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