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The occurrence of frost heave damage in water conveyance channels in cold regions can lead to the deterioration of engineering structures and cause significant water loss during transportation, posing a serious threat to public safety. However, traditional methods to mitigate frost damage, such as replacing foundation soil, become less effective over time as the operational lifespan of the water channels increases, causing recurring frost-related damages. This paper proposes incorporating nano-ZnO into the canal foundation soil to mitigate frost heave damage of the “Yin Da Ru Qin” water conveyance project. Systematic experiments were conducted to assess the effectiveness and underlying mechanisms of this approach. Indoor model tests were first carried out to compare and analyze the differences in frost heave deformation, volumetric water content, and frost depth between the in-situ silt soil (natural silt sampled from the project site without modification) and nano-ZnO-modified soil. The results demonstrate that nano-ZnO addition significantly reduces the frost heave of the soils, with a maximum reduction of 30%. It also inhibits the freezing front’s advancement and impedes water migration within the freezing soil. Furthermore, post-test scanning of both the original and modified soils using nuclear magnetic resonance revealed a significant reduction in the unfrozen water content in the modified soil, providing insight into the microscopic mechanisms of how nano-ZnO alleviates frost heave by regulating water migration pathways. This study introduces a novel technical approach and material selection for the anti-freezing design of water conveyance channels in cold regions, offering valuable theoretical and practical support for the development of anti-freezing technologies for engineering structures in extreme climatic conditions.

Taitema Lake, located in the lower reaches of the Tarim River and the Cherchen River, is one of the most important ecological barriers in Ruoqiang County. The amount of water in Taitema Lake plays an important role in maintaining a healthy cycle within the ecosystem, curbing sandstorms, and improving salinization and desertification. The aim of this study was to reasonably determine the volume of ecological water conveyance by calculating the ecological water demand. We systematically analyzed the spatial and temporal variation characteristics of Taitema Lake during 21 ecological water conveyance processes from 2000 to 2020. The results showed that the area of Taitema Lake increased at a rate of 144% per year because of the Ecological Water Conveyance Project (EWCP). The areas of water in dry, normal, and high flow years were 30.35, 57.76, and 103.5 km2, respectively. The corresponding ecological water demand was 1.58 × 108, 3.09 × 108, and 5.66 × 108 m3, respectively. We calculated that the Cherchen River and the Tarim River carried 0.87 × 108–3.11 × 108 m3 and 0.71 × 108–2.55 × 108 m3 of water, respectively, under different inflow frequencies. This study has significance as a reference for estimates of the ecological water demand of terminal lakes under the condition of artificial water transport in arid inland river basins, and provides the basis for the rational allocation of water resources in the Tarim River Basin.

The water use of desert vegetation is a critical component of ecohydrological processes in arid regions, with groundwater and soil water serving as the primary moisture sources. To better understand the effects of ecological water conveyance on the water sources of desert vegetation, this study employed hydrogen and oxygen stable isotope techniques combined with the Bayesian mixing (MixSIAR) model to analyze changes in water uptake sources of Populus euphratica (of different ages) under varying groundwater depths during ecological water conveyance and non-conveyance periods. The results indicate: (1) The δ 18 O and δ 2 H values of soil water decreased during the water conveyance period compared to the non-conveyance period, gradually increased with distance from the riverbank, and decreased with soil depth. The δ 18 O and δ 2 H values of xylem water increased during the water conveyance period, with the highest values observed in young trees, followed by mature trees, and the lowest in intermediate-aged trees. The δ 18 O and δ 2 H values of groundwater decreased during the water conveyance period and declined with increasing distance from the riverbank. (2) During the water conveyance period (groundwater depth: 1.95–4.73 m), the primary water sources for P. euphratica of different ages were groundwater, river water, and deep soil water, with the maximum utilization proportion of groundwater reaching 23.1%. During the non-conveyance period (groundwater depth: 4.13–6.26 m), the main water sources shifted to groundwater and deep soil water, with the maximum groundwater utilization proportion dropping to 19.9%. As groundwater depth increased, mature trees exhibited the highest reliance on groundwater, followed by intermediate-aged trees, while young trees showed the lowest dependency. (3) The utilization proportion of soil water by P. euphratica increased with higher soil moisture and clay content but decreased with greater groundwater depth. Elevated soil salinity significantly inhibited water absorption by P. euphratica . This study elucidates the adaptive water use strategies of P. euphratica under fluctuating groundwater conditions during ecological water conveyance and non-conveyance periods, providing theoretical support for the ecological restoration of desert riparian forests in the lower Tarim River Basin.

As China’s largest inland river basin and one of the world’s most arid regions, the Tarim River Basin is home to an extremely fragile ecological environment. Therefore, monitoring the water storage changes is critical for enhancing water resources management and improving hydrological policies to ensure sustainable development. This study reveals the spatiotemporal changes of water storage and its driving factors in the Tarim River Basin from 2002 to 2022, utilizing data from GRACE, GRACE-FO (GFO), GLDAS, the glacier model, and measured hydrological data. In addition, we validate GRACE/GFO data as a novel resource that can monitor the ecological water conveyance (EWC) benefits effectively in the lower reaches of the basin. The results reveal that (1) the northern Tarim River Basin has experienced a significant decline in terrestrial water storage (TWS), with an overall deficit that appears to have accelerated in recent years. From April 2002 to December 2009, the groundwater storage (GWS) anomaly accounted for 87.5% of the TWS anomaly, while from January 2010 to January 2020, the ice water storage (IWS) anomaly contributed 57.1% to the TWS anomaly. (2) The TWS changes in the Tarim River Basin are primarily attributed to the changes of GWS and IWS, and they have the highest correlation with precipitation and evapotranspiration, with grey relation analysis (GRA) coefficients of 0.74 and 0.68, respectively, while the human factors mainly affect GWS, with an average GRA coefficient of 0.64. (3) In assessing ecological water conveyance (EWC) benefits, the GRACE/GFO-derived TWS anomaly in the lower reaches of the Tarim River exhibits a good correspondence with the changes of EWC, NDVI, and groundwater levels.

Tunnel Boring Machine (TBM) penetration rate prediction is one of the most important problem in tunneling projects. Estimating of Tunnel Boring Machine (TBM) penetration rate can considerably reduce the costs of tunneling projects. In this study, Datasets including Uniaxial Compressive Strength, Brazilian Tensile Strength, Density and Joint Angle as input parameters and Rate of Penetration as an output parameter. The aim of this study is estimating the penetration rate of tunnel boring machines using fuzzy logic method, Harmony search algorithm (HSA) and Particle Swarm Optimization (PSO) in the Nosoud water conveyance Tunnel. The modeling results showed that the fuzzy model has a significant advantage over the PSO and HSA.

Desert riparian vegetation forms an ecological corridor in extremely arid environments, and ecological water conveyance is an important measure of vegetation restoration and biodiversity conservation in desert riparian zones. Studying the responses of vegetation to ecological water conveyance and changes in this process in arid desert riparian zones and assessing the comprehensive benefits of ecological water conveyance are highly significant for ecological conservation and restoration in addition to the formulation of water transfer policies. Previous studies mainly used a single indicator to evaluate the ecological restoration of the mainstream Tarim River in Northwest China; thus, systematic and comprehensive assessments based on multiple indicators have not been conducted. In the present study, remote sensing data and field surveys were used to analyze the ecological restoration status of the Tarim River during 2015–2021 in terms of hydrological responses, vegetation responses, and ecological water conveyance benefits. The results showed that groundwater levels and soil moisture in the mainstream area of the Tarim River increased significantly from 2015 to 2021. The amount of groundwater storage also increased. Ecological water conveyance has created good hydrological conditions for groundwater recharge and ecological restoration on both sides of the mainstream area of the Tarim River. Desert forest ecosystems, mainly comprising Populus euphratica and Tamarix ramosissima, have been saved and rejuvenated in water conveyance areas. After ecological water conveyance, the Simpson and Shannon–Wiener indices increased significantly, but the diversity level began to decline and then stabilize with the increase in water conveyance frequency. The overall habitat status improved and the quality of the ecological environment below the Wusiman section of the middle reaches of the Tarim River improved significantly.

This study investigates the impact of pipe installation height on the hydraulic performance of a combined canal–pipe water conveyance system (CCPS) and provides practical recommendations. A combined experimental and numerical simulation approach was conducted to systematically analyze and evaluate the impact of different pipe installation heights (0, 1, 3, and 5 cm) and flow rates (18.40, 21.21, 24.74, 28.27, 33.58, and 38.88 L/s) on the system’s behavior. The results indicated that the canal water depths obtained from the numerical simulations were in close agreement with the measurements from the experiments. The water depth in the upstream canal remained nearly parallel to the canal bottom. At the junction, the trend of water depth varies under different flow rates. When the flow rate is low, the water depth sharply decreases. Conversely, when the flow rate is higher, the water depth rises significantly. Cross sections farther from the junction exhibit a higher uniformity in flow velocity distribution. As the height of the pipe installation increases, the range of influence of the junction on the flow velocity distribution in the upstream canal decreases. The elevation of the pipe installation height has been instrumental in enhancing the uniformity of flow velocity distribution across the section. However, the local head loss gradually increases as the installation height increases. Turbulent kinetic energy (TKE) and turbulent eddy dissipation rate (TED) are negatively correlated with the distance between the section and the junction point, and the maximum value decreases gradually with increasing values of the pipe installation height. Considering the hydraulic performance and engineering construction investment, the recommended pipe installation height under the conditions of this study is 1 cm.

Deep‐buried soft soil water conveyance tunnels traversing multiple geological layers are susceptible to structural damage under dynamic internal water pressure. The cross‐layer stratum is particularly sensitive to adverse conditions, such as dynamic internal water pressure and high external water loads. Using the pressurized water conveyance tunnel from the Central Yunnan Water Diversion Project as a case study, numerical analysis of tunnel lining segments under dynamic internal water pressure was conducted using the finite element method (FEM). The mechanical behavior and stress distribution of the lining segments under different water conveyance schemes—including empty, semi‐filled, and filled cases—were systematically analyzed in terms of lining stress, deformation, longitudinal and circumferential displacements, and bolt stress. The results indicate that the lining segments experience the maximum external water pressure under an empty case, with the transverse and longitudinal stresses of the lining bolt identified as a critical weak position. As water transitions from an empty to a semifilled status, horizontal expansion deformation of the lining decreases, stress distribution becomes more uniform, and stress concentrations are observed in the vault region. Further transitioning to a filled status leads to a gradual balance between internal and external pressures, resulting in convergent structural deformation. Moreover, the largest lining deformations occur in cross‐layer stratum where the tunnel passes through soft‐hard soil layers. Additionally, the assembly angle of the lining segments significantly influences the structural stress. As a result, both geological conditions and segment assembly angles should be considered during tunnel design to optimize performance.

Siltation is a significant element that affects the efficiency and safety of water conveyance tunnels. One efficient inspection technique is optical vision inspection carried out by underwater robots. However, efficient processing is required to handle the volume of images that underwater robots collect. Convolutional neural networks (CNNs), have demonstrated considerable promise in computer vision, however it is challenging to implement these models in underwater robots. In this paper, we propose a classification framework for multiple siltation types based on siltation images of water conveyance tunnels using the structure-optimized MobileNet v3, namely SRNet. An underwater robotic image acquisition device is used to acquire the siltation images for training and testing. Out of 6000 images collected from 7 water conveyance tunnels, 4172 are used to train the proposed SRNet network. The remaining 1828 images are used to test it. Furthermore, multiple learning strategies are used to optimize the entire training process. Compared with other deep learning models, the proposed method shows great superiority in terms of recognition results, computational cost and model size. The proposed method effectively weighs model accuracy and complexity and can be used for rapid and accurate identification of siltation in water conveyance tunnel health monitoring.

In order to realize the goal of ice-free water conveyance in the winter for water conveyance projects in cold regions, the operation principle of ice-free water conveyance through channels is described based on the two ice-melting measures of a solar heating gallery and heated storage tank. Based on the multi-year meteorological data and the theory of a product probability event, the concept of a “comprehensive satisfaction rate” was proposed, and then the joint optimal regulating model under two ice-melting measures was established, and the genetic algorithm was used to solve the problem, which solved the important limitations of the economic and efficiency optimization of different ice-melting measures. This paper applies this model to the Zhanghe control gate–Mangniuhe control gate section of the middle route of the South-to-North Water Transfer Project. According to the optimization analysis of a large number of operating conditions, the operating costs of the ice-melting measures have also increased with the increase in the comprehensive satisfy rate. In the operation process, the water temperature along the lines presents a “ladder-like” shape. The average hourly flow and average hourly water temperature of the heated water storage tank have the characteristics of overall unity and local complementarity. With the increase in the water flow and downstream depth before the gate, its operating cost also increases. The increase in the flow velocity at the same time can increase the heat transfer efficiency, reducing the operating costs. In addition, the water temperature of the channel with a solar heating gallery decreased more slowly than that without a solar heating gallery due to its good thermal insulation effect.