Driving forces and their interactions of soil erosion in soil and water conservation regionalization at the county scale with a high cultivation rate

Soil erosion control based on county scale Soil and Water Conservation Regionalization(SWCR)is an essential component of China's ecological civilization construction.In SWCR,the quantitative analysis of the spatial heterogeneity and driving factors of soil erosion among different regions is still lacking.It is of great significance for soil erosion control to deeply examine the factors contributing to soil erosion(natural,land use,and socioeconomic factors)and their interaction at the county and regional levels.This study focused on a highly cultivated area,Hechuan District of Chongqing in the Sichuan Basin.The district(with 30 townships)was divided into four soil and water conservation regions(Ⅰ-Ⅳ)using principal component and hierarchical cluster analysis.The driving factors of soil erosion were identified using the geographical detector model.The results showed thatⅰ)the high cultivation rate was a prominent factor of soil erosion,and the sloping farmland accounted for 78.4%of the soil erosion in the study area;ⅱ)land use factors demonstrated the highest explanatory power in soil erosion,and the average interaction of land use factors explained 60.1%of soil erosion in the study area;ⅲ)the interaction between natural factors,socioeconomic factors,and land use factors greatly contributes to regional soil erosion through nonlinear-enhancement of double-factor enhancement.This study highlights the importance of giving special attention to the effects of land use factors on soil erosion at the county scale,particularly in mountainous and hilly areas with extensive sloping farmland and a high cultivation rate.

Benefit measurement of the soil and water conservation for ecological forestry engineering

Data were collected from Three-north Region, Middle and upper reaches region of Yangtze River and Coastal region. By analysis of factors influencing soil erosion, the longitude, latitude, annual precipitation, and the slope degree were selected as regional independent variables and canopy density and stock litter were selected as independent variables, and integral diffusing models were established for evaluation of the benefit of soil and water conservation of forest. By solving the parameters of models using the package of STATISTICA, the Power function between independent variables and dependent variables was set up. The soil conservation amount of forest and economic values were estimated using the contrast method for the ecological forestry engineering of the above three areas.

Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system

Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.

Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China

Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in inducing loess landslides.This study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide disasters.The variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity test.The experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention capacity.Contrastingly,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest permeability.These results are supported and analyzed by scanning electron microscopy(SEM)observation.In addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of loess.The experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.

基于Transformer语义分割模型的露天矿场识别

露天矿场是生产建设项目水土保持信息化监管的重要对象,对其范围的高效精准识别对于监测非法违规开采行为,加强开采过程中的水土流失预防与治理具有重要意义。基于Transformer深度学习模型提出了露天矿场的遥感影像智能识别方法,并在四川省宜宾市的露天矿场影像数据集上与常用的基于卷积神经网络的深度学习识别方法进行了实验对比。结果表明:该方法对露天矿场范围识别的精确率、召回率、F1-score和IoU指标分别达到91.25%,90.66%,90.95%和83.41%,能够满足水土保持遥感监管的精确度要求;在识别精确度和识别效果上优于对比方法,在运行效率上与对比方法保持在同一数量级,表现出较强的应用价值。该方法在大区域露天矿场范围快速准确识别方面有推广应用潜力。

Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China

Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China.

Compounding soils to improve cropland quality:A study based on field experiments and model simulations in the loess hilly-gully region,China

Increasing the quantity and improving the quality of cropland can alleviate the human-land contradiction and promote the sustainable development of agriculture especially in mountainous areas.With the support of the central government’s policies,Yan’an,Northern Shaanxi,China implemented a major land consolidation engineering project in the loess hilly-gully region from 2013 to 2018,achieving 33,333.3 ha of new cropland.However,the poor quality of some newly-constructed cropland at the initial stage hindered its efficient utilization.In order to overcome this problem,red clay and Malan loess were compounded in different volume ratios to explore the method to improve the cropland quality.The Root Zone Water Quality Model was used to simulate the effects of different soil treatments on soil water,nitrogen and maize growth.Experimental data were collected from 2018 to 2019 to calibrate and validate the model.The root mean square error(RMSE)of soil water content,nitrate nitrogen concentration,above-ground biomass,leaf area index were in the range of 11.72-14.06 mm,4.06-11.73 mg kg^(-1),835.21-1151.28 kg ha^(-1)and 0.24-0.47,respectively,while the agreement index(d)between measured and simulated values ranged from 0.70 to 0.96.It was showed that,compared with land constructed with Malan loess only(T1),the soil structure and hydraulic characteristics of land with a volume ratio of red clay and Malan loess of 2:1(T3)was better.Simulation indicated that,compared with T1,the soil water content and available water content of T3 increased by 14.4%and 19.0%,respectively,while N leaching decreased by 16.9%.The aboveground biomass and maize yield of T3 were 7.9%and 6.7%higher than that of T1,respectively.Furthermore,the water productivity and nitrogen use efficiency of T3 increased by 21.0%and 16.6%compared with that of T1.These results indicated that compounding red clay and Malan loess in an appropriate ratio was an effective method to improve soil quality.This study provides a technical idea and specific technical parameters for the construction or improvement of cropland in loess hilly-gully region,which may also provide reference for similar projects in other places.

三维土工网边坡防护水土保持能力研究

路基边坡防护工程可减轻降雨对坡面土体的侵蚀作用,为深入研究坡面防护材料水土保持能力的定量表征方法,通过室内人工降雨边坡侵蚀模型试验,分析不同降雨强度和不同三维土工网防护下路基边坡的降雨侵蚀规律,提出三维土工网水土保持能力的试验测定方法及相关系数计算公式。研究结果表明:三维土工网防护边坡泥沙流失干质量明显小于相同条件下不设防边坡泥沙流失干质量,土工网防护在减少边坡侵蚀量的同时,有利于边坡侵蚀进程的快速稳定,但土工网的水土保持能力随雨强增大急剧下降。泥沙流失速度随着降雨的持续而逐渐减小,后期趋于收敛稳定,侵蚀历程采用指数函数拟合具有较好的相关性。建议设防边坡的试验降雨时间不少于70 min,不设防的边坡试验降雨时间不小于100 min。水土保持能力系数随雨强的增大呈对数函数关系减小,雨强超过100 mm/h时水土保持能力系数实测值与对数函数拟合值差异较大,建议在测定材料水土保持能力系数时雨强取20~100 mm/h,可取50 mm/h作为标准试验雨强。泡面类三维土工网水土保持能力显著优于普通三维土工网,而双泡面的三维土工网优于单泡面三维土工网。试验条件下凹凸泡面三维土工网的水土保持能力系数主要分布在1.71~3.03,建议50 mm/h雨强三维土工网水土保持能力系数不应小于1.5。

数字孪生水利工程关键技术及其应用实践——以江垭皂市工程为例

围绕数字孪生水利工程建设过程中的新一代信息技术应用深度不够、水利专业模型存在业务缺项等问题和差距,结合数字孪生江垭皂市工程建设实际需求,深入开展数据底板、智能模拟计算模型等关键技术研究与应用。首先,开展了卫星遥感、无人机倾斜摄影测量等技术支撑下的空天地立体监测体系在高精度数据底板构建中的应用研究。然后,基于数字模拟技术和传统水利专业的深度融合,深入开展洪水演进、工程安全等数字水利专业模型的研究,并结合物理工程的同步直观表达进行高保真虚拟建模。最后,通过江垭皂市工程实例对关键技术进行应用分析。研究结果表明构建的数字孪生水利模型与平台能够数字赋能江垭皂市水利工程智慧化管理。

水利大模型的建设思路、构建框架与应用场景初探

发展新质生产力是推动高质量发展的内在要求和重要着力点。推进数字孪生水利建设是推动新阶段水利高质量发展的显著标志和重要路径,模型和知识是数字孪生水利建设的关键所在。因此,按照“需求牵引、应用至上、数字赋能、提升能力”要求,针对水利业务需求融合大模型、水利专业模型和知识而形成“水利大模型”,是发展水利新质生产力的重要引擎。阐述了水利大模型的概念和构建的重要意义,介绍了构建的思路与总体框架,分析了需突破的关键技术,介绍了行业应用场景。研究成果可为人工智能大模型在水利行业落地提供引导和借鉴。

力学在水利水电工程专业课程中的融会贯通——以水工建筑物课程为例

力学课程是水利水电工程专业的基础课程,在整个专业培养教育中起着承上启下的重要作用。以水工建筑物课程为例,总结了材料力学、水力学、土力学等多门力学知识在专业课程中的具体应用;指出力学课程与专业课程的教学应紧密结合,即力学课程的教学应结合专业背景,从传统的“理论模式”向“工程模式”转变,专业课程的教学应从基本的力学原理出发,加深学生对工程问题的理解。

铁路工程建设环水保风险演化研究

研究目的:随着绿色发展理念的提出,对铁路工程建设环境保护和水土保持提出了更高的要求。为顺利完成工程建设环水保目标,识别铁路工程建设环水保风险因素,建立环水保风险演化的系统动力学模型,并以H铁路工程项目为例进行仿真分析,了解风险演化过程,明确风险防控的重点任务。研究结论:(1)在建设过程中环水保风险呈现先增加后稳定的总体趋势,其中开工建设前期为环水保风险的集中涌现阶段;(2)风险因素取值的变化将对环水保风险产生不同程度的影响,其中环水保专项资金不足改变对环水保风险系统影响最大,人员专业能力不足和环境本底调查不全面次之,施工机械污染大变动对系统影响较小;(3)工程项目引入风险预警机制有利于控制环水保风险,预警值的大小将影响风险防控效果;(4)本研究结果可为工程项目防控环水保风险提供借鉴与参考。

基于BIM与GIS的水利水电工程开发设计应用研究

为了解决水利水电项目建设中任务量大、专业技能多、操作难度高、环境干扰严重的问题,往往要进行多次论证和优化工程步骤,保证施工质量。采用BIM(Building Information Modeling)+GIS(Geographic Information System)技术对水利建筑模型进行优化,并对建筑进行外观设计,为模型的搭建提供坚实基础。结果表明,在水利水电项目建设过程中,以BIM+GIS技术模型为基础可快速模拟待查找的工程进度,有利于管控工程资金和监督工程实施进度,可以大幅度提升水利项目的信息化程度。

根土复合体力学效应及其模型构建研究进展与展望

[目的]为探究根土复合体的力学效应机理及模型方法应用。[方法]采用文献分析和对比分析法,归纳分析根土复合体概念和内涵、根土复合体力学效应及力学模型原理、优缺点以及适用范围。[结果](1)根土复合体是根系与土体之间力学耦合效应的复合整体,根系在土体中交叉缠绕,起到加固作用;(2)根系与土体力学关系实质上是根土复合体土力、水力和复合力学特性作用的结果,土力特性、水力特性分别侧重研究根系对土体的影响和土中水分对土体和根系的影响,复合力学特性侧重于根土复合体自身特性对植物根系特征以及结构的直接影响,从而通过三者作用使根系与土体的力学关系处于动态平衡之中;(3)根土复合体复合力学模型研究较土力和水力学模型略少,土力学和水力学模型都是根据量化参数,通过参数间对比来衡量固土效果,但复合力学特性同时涉及土力特性和水力特性,考虑全面,应是未来研究的重点方向。[结论]未来在开展冻融循环、干湿交替、干热循环对不同地区根系与土体相互作用的影响、多类型植物混种抗剪强度、化学作用和微生物作用对土水特性影响机理及复合模型构建等方面有待深入研究。研究结果可为生态脆弱区植被恢复、水土保持和可持续发展等提供重要的理论价值和工程借鉴意义。

Study on Soil and Water Conservation Benefit Models of Grassland Ecosystem──A Case Study on Jianou Mountain Grasslan Ecosystem

This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian province. After anaIysis on the data of soil erosion and runoff coefficient, relations between eroded soil, runoff and slope gradient. we establish soil and water conservation benefit models. According to the mode1s, experiment and inspection results, some proposals have been made to decrease the area of soil erosion in Fujian mountainous areas, e. g., optimizing land use structure in mountainous areas, taking suitable measures for local condition, closing hills for grassland development, accelerating restoration and raising quality of mountain grassland ecosystem, strengthening scientific and technological input, breeding the grass species that are suitable to local physical geographic condition.

黑土区坡耕地水土保持耕作措施对土壤理化性状的影响

为探寻黑土区坡耕地不同水土保持耕作措施对土壤理化性状的影响机理,开展了田间小区试验。设置横坡耕作(TP)、垄向区田(RF)、深松(SF)、横坡耕作+垄向区田(TP-R)、横坡耕作+深松(TP-S)、垄向区田+深松(RF-S)3种水土保持耕作措施及3种组合耕作措施,并以常规顺坡耕作(CK)为对照,分析了土壤孔隙度、土壤机械组成、水稳性土壤团聚体稳定性、土壤养分含量等指标,并采用TOPSIS模型对不同水土保持耕作措施进行了综合评价,筛选了土壤稳定性强且蓄水保肥效果良好的水土保持耕作措施。结果表明:在玉米的全生育期内,深松、垄向区田、横坡耕作均能提高土壤体积含水率。TP-S处理体积含水率最大,0~40 cm土层平均体积含水率较CK处理增加29.47%;RF-S处理平均孔隙度最大,TP-S处理次之,平均孔隙度较CK处理分别增大10.68%、9.25%;TP-S处理能够显著提高土壤稳定性,其中平均质量直径(MWD)、几何平均直径(GMD)和大团聚体含量(R0.25)较CK处理分别增加12.30%、19.57%、13.97%;TP-S处理能够改善土壤机械组成,TP-S处理粗砂粒、粉粒、黏粒含量较CK处理增加15.40%、26.89%、1.90%,细砂粒含量较CK处理降低31.56%;TP-S处理IN(无机态氮)、AP(有效磷)、AK(速效钾)含量最高,较CK处理IN、AP、AK含量分别增加42.81%~55.32%、39.69%~40.68%、20.41%~25.45%。由TOPSIS模型综合评价结果可知,TP-S处理贴合度最高,土壤结构更稳定,且蓄水保肥效果更好,为适宜该地区的水土保持耕作措施。

基于FLUS和InVEST模型的云贵高原土地利用与生态系统服务时空变化多情景模拟研究

[目的]探讨云贵高原不同情景下的土地利用与生态系统服务时空变化,为云贵高原土地利用空间格局优化、生态系统服务功能提升和可持续发展策略制定提供科学依据。[方法]以云贵高原为研究对象,以2001年、2010年和2020年3期MCD12Q1土地覆被数据为基础数据,辅以自然和社会经济数据,基于ArcGIS,FLUS模型和InVEST模型,模拟2030年、2040年和2050年自然发展情景、生态保护情景和耕地保护情景下的土地利用以及碳储量、产水量和土壤保持量3项生态系统服务功能时空分布格局。[结果](1)不同情景下云贵高原的土地利用变化以林地持续增加和草地持续减少为主要趋势;耕地保护情景下,耕地面积最高可占总面积的10.38%;生态保护情景下,林草面积在2050年可达总面积的90%。(2) 3种情景下,云贵高原2020—2050年碳储量和土壤保持量均呈上升趋势,而产水量呈下降趋势。生态保护情景下,2050年碳储量预测值最高,为8.13×10^(9) t;产水量减少速率显著低于另外两种情景,降幅为0.46%。(3)宜昌市、普洱市和常德市等市州的生态系统服务供给能力较高;而贵阳市、毕节市和安顺市等市州的生态系统服务供给能力较低。[结论]云贵高原2020—2050年整体生态系统服务供给能力较好,各项服务功能在不同情景下表现出较强的空间聚集性和异质性。云贵高原今后的生态系统服务管理和可持续发展中,应考虑不同生态系统服务功能的空间异质性以及林地面积持续增加可能带来的水资源失衡问题。

基于创新能力提升的土木水利专业学位研究生培养模式--以内蒙古科技大学为例

目前我国专业学位研究生培养还不能完全满足经济社会高速发展的需求,特别是对于土木水利专业学位研究生而言,其创新能力、实践能力、应用能力培养越来越受到重视;故推进土木水利专业学位研究生教育培养模式创新,提高土木水利专业学位人才培养质量已成为不容忽视的问题。该文基于目前我国土木水利专业学位研究生培养存在的问题,以内蒙古科技大学为例重点从人才培养创新性导向、产教融合培养模式、学位论文应用性导向、“产出”反向促进“培养”和“校内导师+企业导师”指导模式等方面构建以创新能力提升为目标的土木水利专业学位研究生培养模式。

西吉县2022年“7·15”暴雨重力侵蚀调查与建议

2022年7月13—16日黄河中游地区发生强降雨过程,其中宁夏西吉县于7月15日出现的局地强降雨造成严重灾害,为科学评估此次强降雨造成的水土流失危害和水土保持措施的作用,水利部水土保持监测中心及时组织开展了调查工作,其中重力侵蚀专题调查采取无人机影像解译和现场复核相结合的方法获取了西吉县唐家河流域内5条典型小流域发生重力侵蚀的位置、面积及侵蚀量等。对调查结果进行统计与分析表明:此次强降雨在5条小流域内共造成重力侵蚀120处,其中崩塌85处、滑坡29处、泥石流6处,主要发生在新修梯田、道路和荒草地,次暴雨重力侵蚀强度为300~1500 t/km^(2),造成较严重重力侵蚀的原因之一是水土保持工程措施建设标准低、配套设施体系不完备。提出了适当提高水土保持工程建设标准、注重梯田田坎防护、加强道路与沟道排水设施建设等建议。