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Groundwater resources are crucial to socio-economic development and the ecosystem, and over-extraction can cause the groundwater level to drop, deplete reserves, and trigger geological hazards like land subsidence. The North China Plain (NCP) has experienced both subsidence and groundwater depletion due to over-extraction in the past 70 years. In this study, we used MT-InSAR technology and ascending C-band Sentinel-1 SAR data from 2017 to 2023 to study land deformation in the junction area of Shijiazhuang–Baoding–Cangzhou–Hengshui. We identified multiple subsidence funnels with a maximum rate exceeding −150 mm/year and a total deformation surpassing 600 mm. Seasonal decomposition methods accurately separated seasonal signals in the time-series deformation and groundwater level data. An exponential function model applied to long-term deformation showed no significant decrease in subsidence in severely affected areas. By modeling seasonal deformation and seasonal groundwater levels, we determined the elastic skeletal storage coefficients (Ske) to be in the range of 1.02 × 10−3~6.53 × 10−3 in subsidence areas. We obtained the spatiotemporal evolution of the total groundwater storage (TGWS), irreversible ground storage (IGWS), and recoverable ground storage (RGWS). The TGWS and IGWS decreased annually while the RGWS increased, which is attributable to the implementation of the South-to-North Water Diversion Project (SNWDP) and the issuance of groundwater withdrawal policies in the NCP. [ABSTRACT FROM AUTHOR]

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In this paper, an improved axisymmetric interfacial lattice Boltzmann flux solver abandoning the previous predictor-corrector scheme is proposed. Unlike the previous model starting from the two-dimensional standard lattice Boltzmann method (LBM), the present method is developed using the axisymmetric LBM, which directly incorporates the axisymmetric effects into the distribution functions. As a result, the proposed solver does not need the corrector step involving complicated space derivatives. It makes this method simpler and more computationally efficient. In the present solver, the resultant governing equation is globally resolved by the finite volume method, while the fluxes are reconstructed by local application of the axisymmetric LBM. Therefore, the inconsistency between the local reconstruction and the global governing equation can be eliminated because the global equation can be strictly derived from the axisymmetric LBM, which holds stronger physical basis than the previous method. Numerical experiments about the interface capturing and the multiphase flows are conducted to test the proposed model. Results show that the present method is superior to the fractional step solver in terms of the accuracy, stability, and computational efficiency. In addition, this solver has the capacity of simulating large-density-ratio and complex interfacial change. [ABSTRACT FROM AUTHOR]

The recently developed lattice Boltzmann flux solver (PLBFS) for the incompressible porous flow is free from the limitations of coupled streaming time step and the mesh spacing, and the uniform meshes and the complex distribution function treatment at the boundary. However, the local flux reconstruction is inconsistent with the global governing equations in PLBFS. To overcome the drawback, a consistent generalized lattice Boltzmann flux solver for the incompressible porous flow is proposed based on the generalized lattice Boltzmann method (GLBM). The recovered macroscopic governing equations given by the Chapman–Enskog analysis of GLBM are globally resolved by the finite volume method. Specifically, the macroscopic variables are updated at cell centers using the three-step Runge–Kutta method, while the solution of the GLBM is locally applied for the fluxes reconstruction at cell interfaces. Unlike the PLBFS, the forcing term can be naturally incorporated into the interface fluxes reconstruction, which gives the present method a stronger physical basis and ensures global consistency. Moreover, different from the PLBFS, the streaming time step used at the cell interface is decoupled from the updating time step at the cell center in the present solver. Furthermore, a simplified flux reconstruction strategy is proposed to avoid complex calculations and save computing resources. Several numerical examples have been adopted to test the proposed method. The simulations of the nonlinear lid-driven cavity flow show that our method is more accurate than the original PLBFS. Results also demonstrate that the simplified method can reduce the computational time by 43%. [ABSTRACT FROM AUTHOR]

This study focuses on legislative bans imposed on short‐term rentals (STRs) and evaluates their effects on long‐term rentals in Irvine, CA. We find that contract rental prices in the long‐term rental market decrease by 3.0% within approximately 2 years after the enforcement of STR ordinance. The results are primarily driven by the supply side for long‐term rentals. The decline in rents is more pronounced: (1) for long‐term rental units that have similar property characteristics as those listed through Airbnb and (2) for those located in geographic areas with greater Airbnb exposure before the ban was enforced. [ABSTRACT FROM AUTHOR]

In this investigation, two-dimensional flow past square cylinders with slip boundary have been studied with the lattice Boltzmann method. Three modes, which are a single cylinder, an oblique cylinder, and side-by-side cylinders, are investigated with Reynolds numbers from 25 to 200 while relative slip length ranges from 0 to 0.1. It can be concluded that both the flow state and the slip boundary have a great effect on the drag reduction rate. For a single square cylinder, drag forces decrease with larger slip length while the Strouhal number is almost constant. For an oblique cylinder, the slip length also has effects on the stability of the flow except the drag and lift forces. Vortex separation delays with a slip wall of oblique cylinder. For side-by-side cylinders, the jet between two cylinders is not conducive to the drag reduction rate of the slip boundary. Moreover, the application of slip boundary may also lead to additional drag force as vortex separation intensifies, which is extremely different from simple channel flows. Studies have shown that the slip boundary does not always reduce the drag in some complex flow fields. It can be concluded that the drag reduction effect of slip boundaries is more effective in uniform flow. [ABSTRACT FROM AUTHOR]

Urbanization has significantly changed thermal environments and vegetation phenology. However, the effects of spatially different land surface temperatures (LST) on vegetation phenology, rather than differences between urban areas and rural areas, remain unclear. In this study, four cities with similar vegetation types located in temperate monsoon climate zones were selected to map vegetation phenological metrics and discuss their responses to spatially heterogeneous LST within urban areas. First, Sentinel 2-A and 2-B data were used to estimate phenological metrics by combining Savitzky–Golay filtering, and Landsat 8 TIRS data was used to obtain LST. Second, buffer zones (from the urban center to the urban edge at 1 km intervals) were used to extract the averaged phenological metrics and LST. The response of the phenological metrics to LST from the urban center to the urban edge was then analyzed. Results show that spatial differences in LST and vegetation phenology exist inside urban regions as well as between urban and peri-urban areas. In addition, the response of phenology to LST within urban areas is also obvious. SOS is negatively related to spring LST from the urban center to the urban edge, whereas EOS is positively related to autumn LST. [ABSTRACT FROM AUTHOR]

This article examines how the disclosure of local gun‐ownership information affects property values. Using the sudden disclosure of a gun‐ownership map in two New York counties, we explore how home sellers respond to this exogenous information shock. Our results show that an additional permit holder in the neighborhood leads to a 1% decrease in housing prices after the disclosure. This effect is highly localized in that property values are only negatively impacted by gun‐permit holders within 0.1 mi of the focal property. These findings highlight the negative effect of the disclosure of gun‐ownership information on localized home prices. [ABSTRACT FROM AUTHOR]

Carbon (C) inputs, primarily from roots and associated mycorrhizal hyphae, serve as crucial energy sources for microbial-driven C and nitrogen (N) cycling in the soil. However, our understanding of how soil microbial diversity, function, and associated soil properties respond to the exclusion of roots and their associated mycorrhizal hyphae remains limited. In our study, we conducted an experiment with no exclusion of roots or mycorrhizal hyphae (Control), exclusion of roots and retention of mycorrhizal hyphae (NR), and exclusion of roots and mycorrhizal hyphae (NRH) in a Chinese fir (Cunninghamia lanceolata) forest, the most important plantation in China. The soil properties, microbial community diversity and composition, and microbial function were investigated after 2 years of experiment exclusion. We found that exclusion of roots and hyphae significantly decreased DOC, DON, NH4+-N, and NO3−-N, but not SOC, TN, and TP, indicating that the exclusion of roots and mycorrhizal hyphae mainly reduced available C and N concentrations. Meanwhile, the species richness and Chao1 of bacteria and fungi were significantly reduced, primarily due to the decrease in available C and N levels. These findings suggest that the removal of roots and mycorrhizal hyphae results in a decrease in C and N availability, subsequently leading to a loss of microbial diversity. Compared to after the CT treatment, the relative abundances of Proteobacteria and Actinobacteria phyla were reduced after exclusion of roots and hyphae. However, the relative abundances of the phyla Acidobacteria, WPS2, Rozellomycota, and Glomeromycota showed an increase in exclusion treatments. Furthermore, the relative abundances of genes for C degradation (e.g., malQ, malZ, chi, rfbB, bglX, and ablA), C fixation (e.g., accA, icd, korA, and korB), and N fixation (nifS) were increased; conversely, the N degradation genes (e.g., nasA, nirB, ureC, and gdh2) were decreased in treatments involving excluding roots and hyphae. These results, in conjunction with the strong relationships between functional genes and DOC, DON, NH4+-N, and NO3−-N, suggest that microorganisms regulate functional genes to enhance C and N fixation or organic matter decomposition in response to C or N limitation resulting from root and mycorrhizal hypha exclusion. Collectively, our study revealed that the changes in roots-derived C directly altered available C and N in soil, which influenced the microbial community and function, and, in turn, regulated microbial-driven nutrient cycling in forest soils. [ABSTRACT FROM AUTHOR]

Recently, a one-step simplified lattice Boltzmann method abandoning the original predictor–corrector scheme has been proposed for single-phase flows. In this method, the information of non-equilibrium distribution function (DF) is implicitly included in the difference of two equilibrium DFs at two different locations and time levels. Due to this treatment, the one-step method faces challenges such as extra virtual memory cost and additional boundary treatments. To overcome these drawbacks, a novel one-step simplified lattice Boltzmann method (NOSLBM) is developed by directly constructing the non-equilibrium DF with macroscopic variables. The NOSLBM preserves the merits of high computational efficiency and simple code programming in the original one-step method. Moreover, the present method is extended to multiphase flows. One NOSLBM for the solution of the Cahn–Hilliard equation is employed to capture the interface. Another one is adopted to solve the Navier–Stokes equations for the hydrodynamic fields. Numerical tests about interface capturing and single-phase flows indicate that the present method has a better performance on computational efficiency than that of the simplified multiphase lattice Boltzmann method (SMLBM), in which the predictor–corrector scheme is applied. Numerical tests about binary fluids with large density ratio imply the great accuracy and numerical stability of the present method. [ABSTRACT FROM AUTHOR]

Increasing nitrogen (N) deposition profoundly affects nutrient cycling in soil, thereby influencing forest ecosystem productivity and function. Soil microorganisms are integral in driving nutrient turnover; the changes in microbial communities in response to N deposition and the associated soil nutrient availability, especially of limited nutrients, are far from clear. To explore the changes in soil bacterial and fungal communities and their key environmental drivers under N deposition, we conducted a multilevel field N addition experiment in a Castanopsis carlesii natural forest. Soil properties and bacterial and fungal communities were investigated. There were no significant changes in alpha diversities (presented as Chao1 and Shannon's indexes) and beta diversities of bacteria and fungi among the three treatments. Consistently, the relative abundances of dominant bacterial phyla (i.e., Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, and Planctomycetes) and fungal phyla (i.e., Basidiomycota, Ascomycota, and Rozellomycota) did not change following N addition. These results suggest that N deposition did not alter microbial community diversity and structure. In addition, the results of the Mantel test showed that soil pH, NO3−-N, dissolved organic N (DON), and total phosphorus (TP) predominantly influenced the community diversity and structure in bacteria, but not in fungi. Meanwhile, the relative abundance of some sensitive microbial genera, such as Bryobacter, Bradyrhizobium, Sorangium, and Archaeorhizomyces, were significantly decreased. These results indicate a decreased microbial ability for N fixation and P mobilization induced by N deposition. Moreover, there were significant relationships between Bryobacter, Bradyrhizobium, and Archaeorhizomyces and NO3−-N and available P (AP), suggesting that the responses of sensitive microbial groups to N deposition likely depend on the changes in available nutrients in soil, especially limited N or P. Collectively, 6 years of N addition had no significant influence on microbial communities, but some sensitive microbial groups were associated with N or P turnover. This finding emphasizes the critical roles of sensitive microbial species in meditating limited nutrient cycling in soil under climate change. [ABSTRACT FROM AUTHOR]

We examine the iBuyers' business model and their impact on housing markets. We find that iBuyers tend to enter neighborhoods that have more easily priced and homogeneous homes, as price discovery is simpler and more consistent with their pricing algorithm in those areas. iBuyers purchase homes at lower prices than individual owner‐occupiers, and this acquisition discount reflects the benefits iBuyers offer to motivated sellers rather than distressed home purchases or unobserved lower‐quality housing characteristics. Last, a greater presence of iBuyers results in a higher volume of local housing transactions and encourages more home sellers to sell without listing. [ABSTRACT FROM AUTHOR]

Biochar-derived dissolved organic carbon (BDOC), as a highly activated carbonaceous fraction of biochar, significantly affects the environmental effect of biochar. This study systematically investigated the differences in the properties of BDOC produced at 300–750 °C in three atmosphere types (including N2 and CO2 flows and air limitation) as well as their quantitative relationship with biochar properties. The results showed that BDOC in biochar pyrolyzed in air limitation (0.19–2.88 mg/g) was more than that pyrolyzed in N2 (0.06–1.63 mg/g) and CO2 flows (0.07–1.74 mg/g) at 450–750 °C. The aliphaticity, humification, molecular weight, and polarity of BDOC strongly depended on the atmosphere types as well as the pyrolysis temperatures. BDOC produced in air limitation contained more humic-like substances (0.65–0.89) and less fulvic-like substances (0.11–0.35) than that produced in N2 and CO2 flows. The multiple linear regression of the exponential form of biochar properties (H and O contents, H/C and (O+N)/C) could be used to quantitatively predict the bulk content and organic component contents of BDOC. Additionally, self-organizing maps could effectively visualize the categories of fluorescence intensity and components of BDOC from different pyrolysis atmospheres and temperatures. This study highlights that pyrolysis atmosphere types are a crucial factor controlling the BDOC properties, and some characteristics of BDOC can be quantitatively evaluated based on the properties of biochar. [ABSTRACT FROM AUTHOR]

Unlike the lattice Boltzmann method (LBM), the lattice Boltzmann flux solver (LBFS) is free from the limitation of uniform meshes, coupled time step and mesh spacing, and high memory cost. Specifically, the existing interface LBFS (LBFS-CH0) is reconstructed by locally applying the Cahn–Hilliard-based (CH-based) LBM with additional artificial terms. In the framework of LBM, the influence of the additional artificial terms has been assessed. Besides, the comparative study of the CH-based and the Allen–Cahn-based (AC-based) LBM shows that the latter has higher accuracy and stability. Though the LBFS is originated from the LBM, their performances may not be exactly the same. In this study, the AC-based and CH-based LBFS (LBFS-AC and LBFS-CH1) models which can accurately recover the phase field equations are developed from the interface LBM models without any additional terms. The gradient term in the LBFS-AC is discretized by the second-order central difference method. Compared with the LBFS-CH0, the LBFS-CH1 can eliminate the additional terms and recover the true CH equation. Then these interface LBFS models are compared to evaluate their performance and the influence of the additional terms. Different from the LBM, it is found that the CH-based LBFS is superior to the AC-based one in terms of the numerical accuracy and stability. In addition, numerical results show that the additional terms have minor effect on the ability to model the phase interface. This study can provide guidance to ensure the accuracy and stability of interface modeling. Taking into account the accuracy, stability and simplicity, we can conclude that the LBFS-CH0 model could be the first choice to simulate the phase interface in the framework of LBFS. [ABSTRACT FROM AUTHOR]

Recently, a simplified lattice Boltzmann method without evolution of distribution functions was developed. This method adopts the predictor‐corrector scheme to evolve the macroscopic variables. Unlike the original simplified method, we develop a one‐step scheme based on the resultant governing equations given by the Chapman–Enskog expansion analysis of the lattice Boltzmann equation. The proposed method abandons the predictor‐corrector scheme and only needs one step to solve the governing equations without additional intermediate implementation. As a result, the computational efficiency can be improved. In addition, the theoretical analysis demonstrates that the present method has second‐order of accuracy. To treat the boundary, the second‐order approximations for equilibrium distribution functions are employed. To validate the proposed one‐step method, several cases including the Poiseuille flow, the Womersley flow, the Taylor‐Green vortex flow, and the lid‐driven cavity flow are simulated. The numerical results agree with the analytical solutions or the reference data. And the second‐order of accuracy is ensured. Moreover, simulations also suggest that our method has good performances on the numerical stability and the computational efficiency. And the improved efficiency is no less than 30% in our tests. [ABSTRACT FROM AUTHOR]