分类: 地球科学 >> 大气科学 提交时间: 2024-08-14 合作期刊: 《干旱区科学》
摘要: The characteristics of drought in Xinjiang Uygur Autonomous Region (Xinjiang), China have changed due to changes in the spatiotemporal patterns of temperature and precipitation, however, the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region. In this study, we first calculated the standard precipitation evapotranspiration index (SPEI) in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature. Then the spatiotemporal characteristics of temperature, precipitation, and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil–Sen median trend analysis method and Mann–Kendall test. A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor (i.e., temperature and precipitation). The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020, especially the spring temperature and winter precipitation. Due to the influence of temperature, trends of intensifying drought have been observed at spring, summer, autumn, and annual scales. In addition, the drought trends in southern Xinjiang were more notable than those in northern Xinjiang. From 1980 to 2020, temperature trends exacerbated drought trends, but precipitation trends alleviated drought trends in Xinjiang. Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter; in winter, most stations exhibited precipitation-dominated wetting trend. The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought.
分类: 地球科学 >> 水文学 提交时间: 2024-08-14 合作期刊: 《干旱区科学》
摘要: Since the 1950s, numerous soil and water conservation measures have been implemented to control severe soil erosion in the Liuhe River Basin (LRB), China. While these measures have protected the upstream soil and water ecological environment, they have led to a sharp reduction in the downstream flow and the deterioration of the river ecological environment. Therefore, it is important to evaluate the impact of soil and water conservation measures on hydrological processes to assess long-term runoff changes. Using the Soil and Water Assessment Tool (SWAT) models and sensitivity analyses based on the Budyko hypothesis, this study quantitatively evaluated the effects of climate change, direct water withdrawal, and soil and water conservation measures on runoff in the LRB during different periods, including different responses to runoff discharge, hydrological regime, and flood processes. The runoff series were divided into a baseline period (1956–1969) and two altered periods, i.e., period 1 (1970–1999) and period 2 (2000–2020). Human activities were the main cause of the decrease in runoff during the altered periods, contributing 86.03% (–29.61 mm), while the contribution of climate change was only 13.70% (–4.70 mm). The impact of climate change manifests as a decrease in flood volume caused by a reduction in precipitation during the flood season. Analysis of two flood cases indicated a 66.00%–84.00% reduction in basin runoff capacity due to soil and water conservation measures in the upstream area. Soil and water conservation measures reduced the peak flow and total flood volume in the upstream runoff area by 77.98% and 55.16%, respectively, even with nearly double the precipitation. The runoff coefficient in the reservoir area without soil and water conservation measures was 4.0 times that in the conservation area. These results contribute to the re-evaluation of soil and water conservation hydrological effects and provide important guidance for water resource planning and water conservation policy formulation in the LRB.
分类: 地球科学 >> 地球科学其他学科 提交时间: 2024-08-13
摘要: The traditional uniformity coefficient Cu cannot reflect the uniformity of gap-graded granular mixtures. This paper proposes a new index CmuCum to quantify the uniformity of granular mixtures based on the study on their small-strain stiffness G0. The samples of granular mixtures with different fines content (FC) and particle size ratio (PSR) are prepared. The G0 values are determined by quasistatic drained triaxial tests on these samples. The CmuCum values are calculated from the obtained G0 values and can be expressed as a function of FC and PSR. The rationality of the proposed CmuCum is verified. The CmuCum can be used to predict the G0 of granular mixtures when the mechanical coordination number (CNm), shear modulus of particles (Gp), confining stress (σ0) and CmuCum are given.
分类: 地球科学 >> 地质学 提交时间: 2024-08-02
摘要: 目前,干旱和沙漠化等生态问题对植物的生存和适应提出新挑战。因此,探索植物的干旱适应策略对沙 漠人工生态系统的维护和可持续发展具有重要意义。本研究采用灌溉(CK)和干旱(D)两个处理,研究塔克拉玛干沙漠防护林梭梭(Haloxylon ammodendron)和头状沙拐枣(Calligonum caput-medusae)生理生化和形态的适应情况。结果表明:形态上,两种植物的同化枝在干旱胁迫下均显著变短变细;生理上,两种植物在干旱胁迫下光合参数和羧化过程无显著变化,同化枝黎明水势显著降低,头状沙拐枣同化枝正午水势显著降低;生化上,两种植物的叶绿素a、叶绿素b、总叶绿素、光合酶含量在干旱胁迫下无显著变化。两种植物的初始荧光、最大荧光显著降低,梭梭的PSⅡ最大光化学效率显著升高。以上研究表明,两种植物以减缓同化枝生长和维持碳同化的方式抵御干旱。两种植物在干旱胁迫下光合色素活性降低,激发能力下降。头状沙拐枣稳定的叶绿素含量,使光化学系统免受损伤。
分类: 地球科学 >> 地球科学其他学科 提交时间: 2024-08-02
摘要: 为更好地实现区域土壤盐分的监测和治理,促进绿洲可持续发展,本文基于气候、地形、植被等相关数据,结合三工河流域平原绿洲土壤表层盐分调查,对比评估不同模型(随机森林;支持向量机;决策树;普通克里金)土壤盐分反演效果。结果表明:绿洲土壤盐分含量0.29~30.18 g·kg-1,平均值为4.06 g·kg-1,变异系数为149.73%,属于强变异;随机森林模型相较于其他模型具有更高的反演精度,决定系数、均方根误差和绝对平均误差分别为0.73 g·kg-1、1.89 g·kg-1和1.49 g·kg-1;随机森林模型反演显示,高值区主要分布在西北部和中部区域,并且在9种环境协变量中,高程和地下水矿化度对土壤盐分反演精度影响较大。总的来说,以随机森林模型为手段的机器学习方法,不仅能够避免数据的平滑效应和图斑边界两侧的突变,还能有助于识别绿洲局部空间盐分状况,研究结果可为干旱区绿洲土壤盐渍化的长期监测提供技术和方法的参考。
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 耕地利用集约度是提高粮食产量、缓解人地矛盾,实现农业可持续发展的重要保障。本文基于高空间分辨率遥感影像获取的耕地数据,采用综合指标评价模型,探究了2000—2020年“一江两河”地区耕地的集约利用变化及驱动机制。结果表明:(1)近20 a来“一江两河”地区耕地利用集约度有所提升,但总体水平偏低。2020年耕地利用集约度较2000年提高了38.2%,这一提升主要归因于农资投入、技术投入和开发利用水平的增加。(2)各区县间耕地利用集约度变化差异大,在空间上呈现出高集约度区域由东部向西部迁移且范围扩大的变化特征,东西区域间耕地利用集约度差异缩小,低集约度的区县数量减少。(3)灌溉指数、耕地面积比重和耕地质量对“一江两河”耕地利用集约度的独立影响最显著,社会经济因素、农业科技因素和政策环境因素与耕地资源禀赋交互作用下对耕地利用集约度的影响程度增大。基于上述结果,提出以下政策建议:应持续推进“一江两河”地区农业科技创新,重点关注区域差异,实现高集约度地区可持续发展,低集约度地区全要素投入,同时充分发挥农业政策和经济的协同作用,协调促进“一江两河”地区耕地利用集约度提升。
分类: 地球科学 >> 地理学 提交时间: 2024-07-30 合作期刊: 《干旱区地理》
摘要: 2021年10月首批启动了第三次新疆科学考察——“昆仑山北坡水资源开发潜力及利用途径科学考察”。结合多源遥感信息和2022—2023年野外科考工作,对昆仑山北坡的水文水资源变化和水资源利用进行了调查研究。结果表明:(1)1990—2020年,昆仑山北坡山区的气温、降水分别以0.14 ℃·(10a)-1和6.53 mm·(10a)-1幅度增加。(2)冰川变化相对稳定,积雪面积和积雪深度表现为略微增加。(3)永久性水体和季节性水体面积分别显著增加79.89%和144.49%。(4)东昆仑-库木库里盆地的阿牙克库木湖和阿其克库勒湖两大湖泊的水域面积分别增加了68.91%和58.22%,盆地内多条河流具备水资源开发潜力。(5)昆仑山北坡陆地水储量总体呈增加趋势,表现为从西向东增加趋势越加显著。(6)昆仑山北坡的主要河流和田河、克里雅河和车尔臣河年均径流量2010—2023年较1957—2023年分别增加了20.24%、27.85%和45.17%。(7)基于不同气候变化情景模拟预测至21世纪中后叶,主要河流径流量将保持上升态势,区域水资源量总体呈增加趋势。昆仑山北坡的水资源禀赋可为区域绿色高质量发展提供有利的水资源保障条件。
分类: 地球科学 >> 地理学 提交时间: 2024-07-30 合作期刊: 《干旱区地理》
摘要: 定量分析地表水资源开发利用潜力有助于明晰区域水资源禀赋,对区域未来水资源科学规划和可持续开发利用具有重要的指导意义。通过供需水量平衡,从地表径流量、生态需水量、地表水可利用量角度,初步探讨了昆仑山北坡县域单元的地表水资源开发利用潜力,以期为昆仑山北坡科学规划和兵团南进布局提供水资源保障依据。结果表明:(1)昆仑山北坡河流径流2000年后呈显著增加趋势,主要河流2001—2010年年均径流量较2000年以前平均增加了23.36%,2011—2020年较2000年以前平均增加了42.89%,其中车尔臣河增幅最大,和田河增幅最小。(2)车尔臣河流域、克里雅河流域和和田河流域的生态基流量分别为4.67×108 m3、5.38×108 m3和20.26×108 m3,天然植被生态需水量分别为4.34×108 m3、4.00×108 m3和2.62×108 m3。(3)昆仑山北坡各县域单元现状地表水已用水量范围为0.1×108~8.73×108 m3,地表水资源潜力范围为-0.07×108~3.17×108 m3,空间差异非常显著,其中水资源潜力大于2.00×108 m3的有墨玉县、铁门关市38团、策勒县、且末县、和田县、民丰县和洛浦县。现状区域的地表水资源调蓄能力不足,水资源利用上限偏低,虽有潜力但有水难用,未来昆仑山北坡各县域单元需制定修编更为适宜的地表水资源规划并加强基础水利工程建设,提升地表水资源利用效率,为区域高质量发展提供水资源支撑保障。
分类: 地球科学 >> 地理学 提交时间: 2024-07-30 合作期刊: 《干旱区地理》
摘要: 随着青藏高原气候变暖,高原湖泊数量和面积均表现出显著增加趋势,东昆仑-库木库里盆地湖泊扩张亦十分明显。阿牙克库木湖是库木库里盆地最大盐湖,新疆第三次综合科学考察表明,该湖泊已扩张为新疆最大湖泊。基于科考资料,结合遥感卫星资料,对阿牙克库木湖扩张及其流域冰川、冻土、气温和降水等要素进行分析,探讨湖泊水量及其补给水源的关系。结果表明:(1)1990―2023年,阿牙克库木湖面积从623.03 km2扩张至1141.67 km2,2002―2023年湖面水位上升了7.28 m,对应水储量增加了66.64×108 m3。(2)1990―2023年,阿牙克库木湖流域冰川面积减少了16.4 km2,体积减少了1.96 km3。截止2023年,流域分布冰川451条,总面积为324.26 km2。(3)2010年青藏高原冻土分布图显示,流域分布多年冻土12395 km2,季节冻土10652 km2。(4)水量平衡分析表明,冰川和冻土融水径流分别占阿牙克库木湖总入湖水量的9%和5%,季节冻土和多年冻土区降水径流占比为67%,湖面降水量直接补给占比为19%。总体而言,湖泊的扩张主要是流域降水量增加所致。研究揭示了库木库里盆地地表水文过程,可为当地政府优化水资源配置和管理提供参考。
分类: 地球科学 >> 水文学 提交时间: 2024-07-31 合作期刊: 《干旱区科学》
摘要: Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest China. In this study, based on 36 Landsat images, we extracted the glacier boundaries in the Manas River Basin, Northwest China from 2000 to 2020 using eCognition combined with band operation, GIS (geographic information system) spatial overlay techniques, and manual visual interpretation. We further analyzed the distribution and variation characteristics of glacier area, and simulated glacial runoff using a distributed degree-day model to explore the regulation of runoff recharge. The results showed that glacier area in the Manas River Basin as a whole showed a downward trend over the past 21 a, with a decrease of 10.86% and an average change rate of –0.54%/a. With the increase in glacier scale, the number of smaller glaciers decreased exponentially, and the number and area of larger glaciers were relatively stable. Glacier area showed a normal distribution trend of increasing first and then decreasing with elevation. About 97.92% of glaciers were distributed at 3700–4800 m, and 48.11% of glaciers were observed on the northern and northeastern slopes. The retreat rate of glaciers was the fastest (68.82%) at elevations below 3800 m. There was a clear rise in elevation at the end of glaciers. Glaciers at different slope directions showed a rapid melting trend from the western slope to the southern slope then to the northern slope. Glacial runoff in the basin showed a fluctuating upward trend in the past 21 a, with an increase rate of 0.03×108 m3/a. The average annual glacial runoff was 4.80×108 m3, of which 33.31% was distributed in the ablation season (June–September). The average annual contribution rate of glacial meltwater to river runoff was 35.40%, and glacial runoff accounted for 45.37% of the total runoff during the ablation season. In addition, precipitation and glacial runoff had complementary regulation patterns for river runoff. The findings can provide a scientific basis for water resource management in the Manas River Basin and other similar arid inland river basins.
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 为探究不同生境和基质对经过牛消化道的新疆野苹果(Malus sieversii)种子萌发和幼苗生长的影响,根据种子经过牛消化道在野外沉积的不同生境和不同基质,设置3个生境(林缘、林隙、林下)和4种处理[W(经过消化道种子+完整粪便)、P(经过消化道种子 + 破碎粪便)、T(经过消化道种子+土壤)和对照C(未经过消化道种子+土壤)]进行野外控制性试验。结果显示,不同生境和不同处理间新疆野苹果种子萌发率、幼苗存活率和幼苗生物量均有显著性差异(P<0.05)。在林缘生境中,土壤基质的种子萌发率高于粪便基质,而在林隙和林下生境中则相反。林缘和林隙生境下的幼苗存活率显著高于林下。在相同处理下,幼苗生物量表现为林缘>林隙>林下;在相同生境下,林缘和林隙生境的幼苗生物量表现为粪便基质>土壤基质。生境和基质的异质性是影响经过牛消化道的新疆野苹果种子在野外萌发和初期幼苗建成的主要原因。
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 为明析覆膜滴灌条件下水盐氮调控对土壤水盐养分运移变化、棉花生长指标及产量的影响,通过两年三因素全组合大田试验,设置灌水量三水平(W1:2700 m3 ·hm-2、W2:3600 m3·hm-2和W3:4500 m3·hm-2)、含盐量三水平(S1:3 dS·m-1、S2:6 dS·m-1和S3:9 dS·m-1)、施氮量三水平(F1:105 kg·hm-2、F2:210 kg·hm-2和F3:315 kg·hm-2),研究了不同水盐氮组合对土壤水分、盐分、氮素分布及植株生长、产量的影响。结果表明:土壤水分主要聚集在30~40 cm 土层,不同土层深度的含水率基本呈先增大后减小的变化趋势;蕾期和花铃期的 S3F3W1 和 S2F3W1 比S1F3W1的0~40 cm土层平均含水率增大1.3%~21.8%;同一灌溉量下S1F3组合的平均含水率比S1F2和S1F1增大1.39%~13.83%。土壤盐分生育期内呈现先减少后增加的变化趋势;S1土壤盐分随施氮量的增大而先增大后减小,S2、S3土壤盐分随施氮量的增加而减少。W2、W3处理中,氮素在40~60 cm土层中缓慢积聚;S1处理的氮素含量明显高于S2、S3。土壤水分、盐分、氮素含量交互影响,在适宜的土壤水分、氮素条件下,较低的土壤含盐量,能使植株更好地利用养分,利于植株的生长进而促进产量的形成。为获得较高的经济效益,低、中盐土壤推荐灌溉量为3600 m3·hm-2,施氮量为210 kg·hm-2;高盐土壤推荐灌溉量为4500 m3·hm-2,施氮量为315 kg·hm-2。研究为探索干旱区多年膜下滴灌棉花农田生态系统水盐养分运移机制及水肥高效利用提供科学的理论依据。
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 生态网络的构建与优化是遏制景观破碎化和保障区域生态安全的有效途径。以兰西城市群为研究区,以适应性循环理论为基础,耦合粒度反推法与形态学空间格局分析(Morphological Spatial Pattern Analysis,MSPA)识别生态源地,组建“潜力-连通度-韧性”综合生态阻力面,运用电路理论判别生态廊道和关键生态节点,构建生态网络并提出优化对策。结果表明:研究区生态源地空间分布不均且破碎化,总面积4147.84 km2;阻力整体表现为西高东低,并呈以主城为中心向四周递减的趋势;提取生态廊道40条,主要分布在研究区中部,总长度2278.59 km;提取生态夹点24处,多分布在主要河流廊道和生态源地间;判别生态障碍点25处,多位于生态廊道上;生态网络结构指数α、β和γ分别为0.60、2.00和0.74,通过增设12处踏脚石斑块,α、β和γ指数分别提高18.33%、14.00%和9.46%。研究结果可以为兰西城市群国土空间开发及生态安全维护提供参考。
分类: 矿山工程技术 >> 矿山工程技术其他学科 提交时间: 2024-07-08
摘要: Broken coal and rock (BCR) are an important component medium of the caving zone in the goaf (or gob), as well as the main filling material of fault fracture zone and collapse column. The compaction seepage characteristics of BCR directly affect the safe and efficient mining of coal mines. Thus, numerous laboratory studies have focused on the compaction seepage characteristics of BCR. This paper first outlines the engineering problems involved in the BCR during coal mining including the air leakage, the spontaneous combustion, the gas drainage, and the underground reservoirs in the goaf. Water inrush related to tectonics such as faults and collapse columns and surface subsidence related to coal gangue filling and mining also involve the compaction seepage characteristics of BCR. Based on the field problems of BCR, many attempts have been made to mimic field environments in laboratory tests. The experimental equipment (cavity size and shape, acoustic emission, CT, etc.) and experimental design for the BCR were firstly reviewed. The main objects of laboratory analysis can be divided into compression tests and seepage test. During the compaction test, the main research focuses on the bearing deformation characteristics (stress-strain curve), pore evolution characteristics, and re-crushing characteristics of BCR. The seepage test mainly uses gas or water as the main medium to study the evolution characteristics of permeability under different compaction stress conditions. In the laboratory tests, factors such as the type of coal and rock mass, particle size, particle shape, water pressure, temperature, and stress path are usually considered. The lateral compression test of BCR can be divided into three stages, including the self-adjustment stage, the broken stage, and the elastic stage or stable stage. At each stage, stress, deformation, porosity, energy, particle size and breakage rate all have their own characteristics. Seepage test regarding the water permeability experiment of BCR is actually belong to variable mass seepage. While the experimental test still focuses on the influence of stress on the pore structure of BCR in terms of gas permeability. Finally, future laboratory tests focus on the BCR related coal mining including scaling up, long term loading and water immersion, mining stress path matching were discussed.
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 利用1961—2019年青海省42个气象站逐日最低气温,分析不同等级寒冷日数时空演变特征。结果表明:(1)1961—2019年青海省寒冷日数随着等级降低而逐渐增加,主要以微寒日数为主;总寒冷日数整体呈减少趋势,显著快速减少的突变发生在1995年;总寒冷日数减少主要是由酷寒日数的减少引起;1997年气候突变后严寒、大寒、小寒、轻寒、微寒和总寒冷日数变化趋势减少,酷寒日数变化趋势增多,极寒和凉日数变化趋势减少与增加分布相当。(2)青海省寒冷日数表现出明显的空间差异,总寒冷日数随着海拔升高逐渐增加,等级较高寒冷日数增减趋势较明显,随着寒冷等级的降低,增减趋势向低纬度和海拔相对较低的地区发展。(3)极寒、酷寒、严寒、轻寒、微寒和总寒冷日数随年平均气温升高而逐渐减少,大寒、小寒和凉日数随年平均气温升高而逐渐增加。(4)青海省除了严寒日数其余等级寒冷日数存在持续性,未来下降趋势将持续,但持续性强度不尽相同。
分类: 地球科学 >> 地理学 提交时间: 2024-07-30 合作期刊: 《干旱区地理》
摘要: 氢氧稳定同位素作为示踪剂被广泛用于水文循环过程研究。地表水是水循环的重要组成部分,是区域水汽来源和现代水文过程分析的有效载体。基于新疆第三次科学考察,于2018年8月至2023年8月在昆仑山北坡采集了地表水样本并测量其氢氧稳定同位素数据,同时汇编了区域以往的地表水同位素数据,分析了昆仑山北坡地表水氢氧稳定同位素的空间分布特征。结果表明:(1)昆仑山北坡地表水同位素值呈现出西低东高的空间变化特征,区域地表水线为δ2H=5.98×δ18O-6.86(R2=0.65,n=141)。(2)对比昆仑山北坡地表水和降水氢氧稳定同位素值发现地表水同位素平均值普遍低于加权降水同位素值。(3)昆仑山北坡地表水同位素空间格局受到西风携带的外来水汽和局地再循环水汽共同影响,此外蒸发也会改变区域地表水同位素值。
分类: 矿山工程技术 >> 矿山工程技术其他学科 提交时间: 2024-07-08
摘要: Simulation of subsurface energy system involves multi-physical processes such as thermal, hydraulical, andmechanical (THM) processes, and requires a so-called THM coupled modeling approach. THM coupled modelingis commonly performed in geothermal energy production. However, for hydrocarbon extraction, we need toconsider multiphase flow additionally. In this paper, we describe a three-dimensional numerical model of non-isothermal two-phase flow in the deformable porous medium by integrating governing equations of two-phasemixture in the porous media flow in the reservoir. To account for inter-woven impacts in subsurface condi-tions, we introduced a temperature-dependent fluid viscosity and a fluid density along with a strain-dependentreservoir permeability. Subsequently, we performed numerical experiments of a ten-year water flooding pro-cess employing the open-source parallelized code, OpenGeoSys. We considered different well patterns with colderwater injection in realistic scenarios. Our results demonstrate that our model can simulate complex interactions oftemperature, pore pressure, subsurface stress and water saturation simultaneously to evaluate the recovery per-formance. High temperature can promote fluid flow while cold water injection under non-isothermal conditionscauses the normal stress reduction by significant thermal stress. Under different well patterns the displacementefficiency will be changed by the relative location between injection and production wells. This finding hasprovided the important reference for fluid flow and induced stress evolution during hydrocarbon exploitationunder the environment of large reservoir depth and high temperature.
分类: 矿山工程技术 >> 矿山工程技术其他学科 提交时间: 2024-07-08
摘要: The key to achieving rockburst warning lies in the understanding of rockburst precursors. Considering the correlation characteristics of rockburst acoustic emission (AE) parameters, a self-organizing map neural network (SOMNN) based method for rockburst precursor inversion was proposed. The feature of this method lies in acyclic data segmentation iteration process based on the thinking of "interference signal screening", "key signal extraction", and "precursor signal inversion". The rationality of this method has been verified in three groups of rockburst experiments. The results revealed that rockburst AE precursor signals consist of a series of signals characterized by long duration, high energy, low average frequency, high energy amplitude, and low peak frequency. Subsequently, potential value in long term rockburst warning of the precursor obtained in this study was shown via the comparison of conventional precursors. Finally, a preliminary interpretation for rockburst precursor was proposed under the framework of AE parameters physical significance, and it is revealed that AE precursor signals are likely linked to the creation of large-scale tensile cracks before rockburst
分类: 矿山工程技术 >> 矿山工程技术其他学科 提交时间: 2024-07-08
摘要: Rockburst is a phenomenon where sudden, catastrophic failure of the rock mass occurs in underground deep regions or areas with high tectonic stress during the excavation process. Rockburst disasters endanger the safety of people’s lives and property, national energy security, and social interests, so it is very important to accurately predict rockburst. Traditional rockburst prediction has not been able to find an effective prediction method, and the study of the rockburst mechanism is facing a dilemma. With the development of artificial intelligence (AI) techniques in recent years, more and more experts and scholars have begun to introduce AI techniques into the study of the rockburst mechanism. In previous research, several scholars have attempted to summarize the application of AI techniques in rockburst prediction. However, these studies either are not specifically focused on reviews of the application of AI techniques in rockburst prediction, or they do not provide a comprehensive overview. Drawing on the advantages of extensive interdisciplinary research and a deep understanding of AI techniques, this paper conducts a comprehensive review of rockburst prediction methods leveraging AI techniques. Firstly, pertinent definitions of rockburst and its associated hazards are introduced. Subsequently, the applications of both traditional prediction methods and those rooted in AI techniques for rockburst prediction are summarized, with emphasis placed on the respective advantages and disadvantages of each approach. Finally, the strengths and weaknesses of prediction methods leveraging AI are summarized, alongside forecasting future research trends to address existing challenges, while simultaneously proposing directions for improvement to advance the field and meet emerging demands effectively.
分类: 地球科学 >> 地理学 提交时间: 2024-06-12 合作期刊: 《干旱区研究》
摘要: 针对新疆土壤盐分信息获取困难,无法快速、准确的大范围评估土壤盐渍化情况,本研究以新疆阿拉尔垦区的棉田为研究对象,利用Sentinel-2 SR和Landsat-9 OLI的多光谱遥感影像数据,采用穷举特征组合和交叉验证方法,从20个光谱指数和组合光谱指数构建的高维数据集中筛选出最优特征子集,并比较四种机器学习模型(即XGBoost、随机森林、深度神经网络和K-近邻)在不同特征组合下的土壤盐渍化反演精度,同时分析Sentinel-2 SR和Landsat-9 OLI遥感影像在土壤盐渍化反演中的精度差异。研究结果表明:(1) 基于XGBoost算法构建的模型能够实现棉田盐渍化高精度预测,不同特征组合的R2均高于0.74,MSE均低于0.04,MAPE低于0.13。(2) 在特征组合1条件下,Sentinel-2 SR(S3+GBNDVI)与Landsat-9 OLI(SI+NDVI)遥感影像使用XGBoost算法均获得了最高预测精度。(3) Sentinel-2 SR影像数据在棉田盐渍化预测中的精度(R2=0.73~0.88)优于Landsat-9 OLI影像数据。本研究实现了新疆阿拉尔垦区棉田土壤盐渍化精准监测,为垦区棉田土壤盐渍化治理和防治提供有效的技术参考。