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The continuous exploitation of groundwater has made wetland degradation an ecological and geological environmental problem that cannot be ignored and has had impacts on the ecological environment and human production and life. In this study, Modflow was used to simulate the wetland‐aquifer interaction during the multiyear pumping process, establish a quasi‐ideal model of wetlands based on the actual area of the Baiyangdian Basin, simulate the relationship of water quantity change between wetlands and piedmont plain aquifers during groundwater exploitation and its natural recovery process, and quantify the attenuation of the contribution of groundwater to wetlands caused by groundwater overexploitation. Two components of wetland water reduction are explored through the simulation and calculation of wetland‐aquifer interactions under different exploitation conditions. The results show that in the process of groundwater exploitation, the impact of groundwater overexploitation on wetland degradation is mainly divided into two parts: one is the reduced base flow from the piedmont plain to the wetland, and the other is the induced infiltration caused by the reverse recharge of groundwater from the wetland due to the pumping effect. Compared with the wetland water reduction during the pumping process, the process of water recovery during the natural recovery process is much slower, which indicates the residual effect of exploitation will continue for a long time. The findings provide a scientific reference for the management of water resources in wetland areas. [ABSTRACT FROM AUTHOR]

The complexity of aquifers poses a challenge for fully comprehending the impact of climate change on groundwater. In this study, we employed a suite of hydrological and statistical methods, including the water table fluctuation (WTF) method, wavelet analysis, the Hurst exponent, and temporal trend analysis, to assess groundwater storage (GWS) changes and their correlation with precipitation in Alabama, located in the southeastern United States. These approaches were used to evaluate the temporal variability of GWS as derived from well data and large-scale model estimates that incorporated satellite observations. The results unveiled a nuanced and regionally variable relationship between GWS changes and precipitation over the past two decades. While the Mann–Kendall test did not reveal any statistically significant overarching trends in GWS changes, Sen's slope analysis indicated subtle regional variations, including a minor decline of −0.2 mm/year for GWS in southern Alabama and modest increases of 0.5 mm/year and 0.38 mm/year in the western and northern regions, respectively, from 2000–2021. Wavelet coherence analysis showed significant co-variation between GWS and precipitation in cycles ranging from 8 to 32 months, suggesting potential cyclic or intermittent influences. Furthermore, we detected strong persistence within the groundwater system using the Hurst exponent, indicating the substantial temporal memory impact. These findings are useful for developing effective groundwater management strategies in a changing climate. [ABSTRACT FROM AUTHOR]

Portunus trituberculatus is a very important marine economic species, and its aquaculture industry has been developing rapidly. However, the phenomenon of marine wild capture of P. trituberculatus and germplasm degradation has become increasingly serious. It is necessary to develop the artificial farming industry and carry out germplasm resource protection, for which sperm cryopreservation technology is an effective method. This research compared three methods (mesh-rubbing, trypsin digestion, and mechanical grinding) for acquiring free sperm, and the best method was mesh-rubbing. Then, the optimal cryopreservation conditions were selected, and the optimal formulation was sterile calcium-free artificial seawater, the optimal cryoprotectant was 20% glycerol, and the best equilibrium time was 15 min at 4 °C. The optimal cooling program was suspending the straws at 3.5 cm on the liquid nitrogen surface for 5 min and then storing them in liquid nitrogen. Finally, the sperm were thawed at 42 °C. However, the expression of sperm-related genes and the total enzymatic activities of frozen sperm were significantly decreased (p < 0.05), which showed that sperm cryopreservation damaged the sperm. Our study improves the sperm cryopreservation technology and the yield of aquaculture in P. trituberculatus. Additionally, the study provides a certain technical basis for the establishment of a sperm cryopreservation library of crustaceans. [ABSTRACT FROM AUTHOR]

The Rouse formula and its variants have been widely used to calculate the steady-state vertical concentration distribution for suspended sediment in steady sediment-laden flows, where the diffusive flux is assumed to be Fickian. Turbulent flow, however, exhibits fractal properties, leading to non-Fickian diffusive flux for sediment particles. To characterize non-Fickian dynamics of suspended sediment, the current study proposes a Hausdorff fractal derivative based advection-dispersion equation (HADE) model, where the Fickian diffusive flux in the Rouse model is replaced by a fractal derivative re-scaled using a constant diffusivity. The order of the Hausdorff fractal derivative is designed to characterize the influence of the multi-fractal turbulence structure on sediment diffusion. Applications show that the HADE model, with the analytical solution expressed using a stretched exponential function, can accurately describe the observed vertical concentration profiles for suspended sediment with different sizes. This improvement well captures the non-exponential decay of the vertical sediment concentration in turbulent flow. Further analyses of measured sediment concentration profiles reveal that the Hausdorff fractal order decreases with the Rouse parameter, which describes the stronger impact of turbulent flow and a more uniform sediment concentration profile for smaller particles. Model comparisons also show that the HADE model provides better performance in describing the sediment concentration profiles than the improved Rouse formula and the standard fractional derivative advection-dispersion equation (FADE), which either under- or over-estimates vertical displacement of sediment particles, likely due to coherent turbulent structures. [ABSTRACT FROM AUTHOR]

The value of ecosystem services and service capabilities continue to improve, and the way to form a path of resource industrialization development has become one of the important directions of sustainable development. This paper mainly takes the construction of national parks as a major opportunity and explores the temporal and spatial changes in the value of ecosystem services in Qilian Mountain National Park (Gansu area) and the construction path of the industrial system of national park construction. The total value of ecosystem services was calculated using a comprehensive index of the degree of land use, land contribution rate, ecological service value, equivalent factor of economic value, and the improved value coefficient of farmland ecological services, and then the Sensitivity index was used to reveal the dependence of the value of ecosystem services on the value index over time. The results showed the following: (1) Human disturbance factors in Qilian Mountain National Park (Gansu area) are weak, and the land use of Qilian Mountain National Park (Gansu Area) was mainly grassland, followed by unused land, forest land, and glacial snow, with the change in glacial snow cover being the largest. (2) The ecosystem of Qilian Mountain National Park (Gansu area) is strong, and the contribution rate of forest land, construction land, unused land, and glacial snow cover in Qilian Mountain National Park (Gansu Area) was positive, while cultivated land, grassland, and water area were negative. Among them, glacial snow cover contributed the most at 10.4723 the ecological barrier function plays a stable role. (3) The ecosystem service value (ESV) in Qilian Mountain National Park (Gansu Area) showed a fluctuating growth trend on the whole, showing the characteristics of high northwest and low southeast, among which the total value of grassland was the largest, the value of unused land was the smallest with the largest increase range, and the increase in water area was the smallest. (4) Qilian Mountain National Park (Gansu Area) is mainly based on regulated services, followed by support services, supply services, and cultural services, all showing a clear growth trend, increasing by 181.77%, 183.90%, 196.19%, and 170.38%, respectively. With the development of low-carbon economy and circular economy as the main idea, we aim to build a national park industrialization development path of direct product supply, indirect product supply, and basic guarantee. [ABSTRACT FROM AUTHOR]

Studies on groundwater have traditionally been based on declining groundwater levels and associated ecological, environmental, and geological problems. However, due to extreme hydrometeorological events and human activities, rising groundwater levels have been observed in many areas. The daily groundwater levels from 2018 to 2020 for the Poyang Lake Basin (PLB) in Jiangxi Province were recorded. The statistical characteristics of abnormal groundwater level rising (AGLR) events and the factors influencing the dynamic changes in groundwater level were analyzed using geostatistical methods and outlier identification methods. The groundwater level in the lower terrain of the PLB has increased significantly in recent years. AGLR events identified by the median absolute deviation and interquartile range methods showed that AGLR events mainly occurred in the spring and summer and were mainly distributed near the surface water bodies. Correlation analysis of the factors influencing the groundwater level revealed that the correlation between precipitation and groundwater level was related to topography. In contrast, the correlation between river stage and groundwater level was related to runoff volume. [ABSTRACT FROM AUTHOR]

The one‐dimensional (1‐d), constant‐parameter heat transport equation (HTE) built upon Fourier's law proposed in 1822 has been widely used to model heat transport in soil, where the core question is how to fit the observed temperature time series without detailed geomedium heterogeneity being mapped in the model. To address this question, this study extended the classical HTE by adding one parameter (the time index) using the time subordination approach to capture the impact of random operational times spent by individual heat parcels on heat dynamics. This led to a parsimonious, 1‐d, Subordinated HTE (Sub‐HTE), which assumes the temporally non‐Fourier heat transport and contains the classical HTE as an end member, with analytical solutions aimed at upscaling local heat transport in heterogeneous porous media. To test this approach, temperature time‐series were collected in unsaturated soils built in the laboratory that were subjected to periodic surface temperature fluctuations. Model applications showed that, although the HTE captures the general shape of the observed temperature time series, the Sub‐HTE is a mild improvement of the HTE in characterizing the nuances of temperature amplitude attenuation (likely due to the small operational time at the intermediate/late time stages). Both Eulerian and Lagrangian frameworks were developed to interpret other dynamics in heat flow, including the early time temperature jump and phase advance. Parameter analyses also revealed that the thermal front velocity in the Sub‐HTE is a function of Darcy flux, the time index, and the system's thermal properties, while the thermal diffusivity (the only parameter related to thermal properties in the Sub‐HTE) can be scale independent. Therefore, the 1‐d Sub‐HTE can be a reliable generalization of the classical 1‐d HTE in upscaling heat transport in soil. Plain Language Summary: Heat penetrates every substance on Earth, and the accurate quantification of heat transfer has important meanings for hydrologic and ecological studies and applications. Heat transport in soil was usually calculated by classical models built upon the standard Fourier's law which assumes that the conductive heat flux is proportional to the temperature gradient. These classical models and heat transfer theories work well for homogeneous media. Natural geological media, however, are typically heterogeneous, where heat transport tends to exhibit different dynamics, especially the delayed transfer. This study proposed a new heat transfer model by assuming the random process for heat parcels moving in porous media under complex boundary conditions. Applications showed that the new model and the corresponding analytical solutions can capture thermal transport observed in various media, including unsaturated sand columns built in the lab. Model comparison also revealed that main dynamics of heat transfer in porous media, including phase advance and amplitude attenuation, can be better characterized by the new model than the classical one. Key Points: Subordinated heat transport equation with analytical solutions is developed to model heat moving in heterogeneous soil with complex flowThe model was tested by conducting laboratory and numerical experimentsMathematical interpretation is provided to explain phase advance and enhanced amplitude damping observed in the lab or numerical tests [ABSTRACT FROM AUTHOR]

The fractional Brownian motion (fBm) and fractional Lévy motion (fLm) can easily describe the geometry and the statistical structure of hydraulic conductivity (K) for real‐world. However, the fBm and fLm models have not been systematically evaluated when building the K field for a low‐permeability site. In this study, both the fBm and fLm are used to simulate the low‐K field at NingCheGu (NCG), Tianjin, China. Groundwater flow and solute transport are then computed using MODFLOW and MT3DMS, respectively, and the influence of the fBm/fLm models for K on groundwater flow and solute transport is discussed. Results show that the fLm fits better the statistics of the low‐K medium than fBm, and the random logarithmic K (LnK) field generated by fLm is more stable because the resultant LnK field captures more of the measured properties at the field site than that generated by fBm. In contrast, the LnK generated by fBm is more likely to form both high‐K channels and low‐K barriers. The fBm therefore predicts more extreme behaviours in flow and transport, including the preferential flow, low‐concentration blocks and solute retention. The overall groundwater renewal period and solute travel time for the fLm simulation are slightly shorter than those for fBm. The impacts of the fLm and fBm models on the statistics of the resultant LnK fields and the dynamics of groundwater flow and solute transport revealed by this study shed light on the selection and evaluation of the fractional probability distribution models in capturing the K fields for low‐K media. [ABSTRACT FROM AUTHOR]

Industrial ecology is an advanced form and ideal model of modern industrial development, in which the industrial ecosystem is the core. Based on the PSR model, this paper builds a comprehensive evaluation index system for urban industrial ecosystem development and selects 14 prefecture-level cities in Liaoning Province of the traditional industrial area in Northeastern China as cases to calculate the development level of its industrial ecosystem during 2000–2018 using an improved Topsis method and then to conduct a spatial visualization analysis. Finally, based on the "stress-state-response" subsystem, this paper diagnoses the constraints for industrial ecosystem development, which can provide a reference basis for decision-making in industrial ecology of traditional industrial area represented by those in Northeast China. The results show the following: (1) From 2000 to 2018, the industrial ecology of the 14 cities in Liaoning Province was at a medium level. Except for Shenyang and Dalian with the rapid development, the difference of industrial ecosystem development for other cities was relatively small. (2) From 2000 to 2018, the industrial ecosystem development of each city was in a status of "either increasing, or decreasing, or fluctuating," which generally raised first and then decreased. Regarding spatial difference, the development exhibited a "center-periphery" pattern, with Shenyang and Dalian as the "dual-core" that were increasingly strengthened with significantly high-level industrial ecology. (3) At system level, PSR constraint grades for the industrial ecosystem development in the 14 cities of Liaoning Province were different. Constraint grades in the pressure subsystem, the state subsystem, and the response subsystem for the industrial ecosystem of Liaoning were 45.73%, 20.01%, and 34.34%, respectively, indicating that the lack of human response to the ecological environment and the pressure of human activities on the ecological environment during the industrial economy development were the main constraints affecting the process of industrial ecology in these cities. (4) Due to the differences in geographical environments, economic bases, industrial structures, and local development contexts, the major constraint factors of industrial ecosystem development in different cities are significantly different and complicated; however, there are five factors that are generally considered as major constraint factors in all cities, i.e., regional GDP, number of labor force employed in the secondary industrial sector, gross investment in fixed assets, amount of industrial sulfur dioxide removal, and production value from "three-wastes" comprehensive utilization. At last, this paper puts forward some recommendations and suggestions for providing scientific support for industrial ecosystem construction in the traditional industrial area of Northeastern China. [ABSTRACT FROM AUTHOR]

To better understand the agricultural resources and environmental problems of the provinces along The Belt and Road in China, it is critical to investigate their agricultural carbon emission efficiency and evolutionary trends. Based on the panel data of 18 key provinces and cities between 2006 and 2015, this paper evaluated the agricultural carbon emission efficiency with the data envelopment analysis–Malmquist model and further explored their dynamic evolutionary trends. There were several main findings. First, the efficiency levels of agricultural carbon emissions showed significant regional differentiation among the areas, with that along the 21st-Century Maritime Silk Road being much higher than that along the Silk Road Economic Belt. Second, technical efficiency was the key factor that restricted the improvement of the comprehensive efficiency of agricultural carbon. Third, most provinces invested in too many redundant and unreasonably allocated resources, showing a trend of diminishing returns to scale. Last, According to dynamic evolution analysis, the total productivity still demonstrated a diminishing trend. This paper provides some suggestions for effectively improve the efficiency of agricultural carbon emissions in China, such as optimize the agricultural industrial structure, increasing the investment of carbon emission reduction technology, and implementing a carbon emission quota clearing system. This paper contributes to the improvement of the environment in China. [ABSTRACT FROM AUTHOR]

Abstract: Interactions of surface water and groundwater (SW–GW) play an important role in the physical, chemical, and ecological processes of riparian zones. The main objective of this study was to describe the two‐dimensional characteristics of riverbank SW–GW interactions and to quantify their influence factors. The SW–GW exchange fluxes for six sections (S1 to S6) of the Qinhuai River, China, were estimated using a heat tracing method, and field hydrogeological and thermodynamic parameters were obtained via inverse modelling. Global sensitivity analysis was performed to compare the effects of layered heterogeneity of hydraulic conductivity and river stage variation on SW–GW exchange. Under the condition of varied river stage, only the lateral exchange fluxes at S1 apparently decreased during the monitoring period, probably resulting from its relatively higher hydraulic conductivity. Meanwhile, the SW–GW exchanges for the other five sections were quite stable over time. The lateral exchange fluxes were higher than the vertical ones. The riverbank groundwater flow showed different spatial variation characteristics for the six sections, but most of the higher exchange fluxes occurred in the lower area of a section. The section with larger hydraulic conductivity has an apparent dynamic response to surface water and groundwater level differences, whereas lower permeabilities severely reduced the response of groundwater flow. The influence of boundary conditions on SW–GW interactions was restricted to a limited extent, and the impact extent will expand with the increase of peak water level and hydraulic conductivity. The SW–GW head difference was the main influence factors in SW–GW interactions, and the influence of both SW–GW head difference and hydraulic conductivity decreased with an increase of the distance from the surface water boundary. For each layer of riverbank sediment, its hydraulic conductivity had greater influence on its groundwater flow than the other layers, whereas it had negligible effects on its overlying/underlying layers. Consequently, the variations in river stage and hydraulic conductivity were the main factors influencing the spatial and temporal characteristics of riverbank groundwater flow, respectively. [ABSTRACT FROM AUTHOR]

Hyporheic exchange induced by dunes is a key process controlling water fluxes and biogeochemical processes in river networks. Owing to the limitations of instrumental detection at small spatial scales, previous studies have focused mainly on dune-induced hyporheic exchange in homogeneous systems. A low-permeability lens is a natural, widespread heterogeneity in stream beds, and probably affects the processes of water flow and contaminant transportation significantly. To quantitatively analyse the response mechanism of hyporheic exchange to a low-permeability lens, a two-dimensional dune-generated hyporheic exchange model was developed using the VS2DH model. The results indicate a lens in a stream bed can hinder or enhance hyporheic exchange processes, depending on its relative spatial location to dunes. Both the increase in length and thickness of the lens could strengthen its impacts on hyporheic exchange. Regional groundwater-surface water interactions of higher intensity suppress the flow of hyporheic exchange in a stream bed with a low-permeability lens. [ABSTRACT FROM AUTHOR]

Considering the significance and importance of urban sustainability in China and China's history of rapid urbanisation and industrialisation, this paper aims to incorporate the investigation of climate change and air pollution in urban sustainability research in China through a driver-pressure-state-impact-response model. The model has 12 indices: population, enterprise, registered vehicles, energy consumption, emissions and concentrations of carbon dioxide and sulfur dioxide, land use change, annual temperature, tropical nights and reforestation were selected. It was used in the analysis of 14 cities in the Liaoning Province. The results show that the model is an effective tool for urban sustainability research, allowing for the investigation of interactions of climate change and air pollution and contributing to the body of knowledge by aiding generation of realistic and practical measures. [ABSTRACT FROM AUTHOR]

Resilience and efficiency are the core concepts of sustainable management of agricultural water resources system. This study constructed an evaluation system of the efficiency and resilience of agricultural water resources system (E AWRS , R AWRS) in the Yellow River Basin by comprehensively applying the analytic hierarchy process (AHP), entropy method (EVM), SBM-DEA model, and the development coordination model. The results showed that: (1) From 2005–2019, the E AWRS and R AWRS showed a fluctuating upward trend. The E AWRS increased significantly, especially the Baihe, Heihe, Luohe and Wudinghe river basins grew at a faster rate. However, the overall efficiency levels were still not high, and all the 72 prefecture-level administrative units were inefficient areas. The R AWRS was at a relatively low level, in which the Huangshui, Taohe and Qingshuihe river basins had rapid growth in resilience. (2) From the perspective of spatial differentiation characteristics, the E AWRS in Sichuan, Qinghai, Inner Mongolia, Shaanxi, Henan, and Shandong was relatively high, while that in Gansu, Shanxi and Ningxia was relatively low. The prefecture-level administrative units of the upstream river source area, Hetao Irrigation District, Fenwei Plain and Huanghuaihai Plain had a relatively high E AWRS. The R AWRS in the lower reaches was significantly better than that in the upper and middle reaches. (3) The development degree of the agricultural water resources system has gone through a process of rapid rise (2005–2013) - fluctuating growth (2014–2017) - rise (2018–2019), showing an "upstream-midstream-downstream" stepwise increasing pattern. The coordination degree of the agricultural water resources system showed a downward trend, and the decrease showed an "upstream-downstream-midstream" increasing pattern. (4) The three clusters divided by the average value of the development degree and coordination degree of the agricultural water resources system showed the changes from concentration to dispersion, in contrast, the coordination degree was gradually decreased. • Agricultural water efficiency and resilience evaluation was completed. • Spatial–temporal characteristics of agricultural water efficiency and resilience was presented. • The influencing factors of agricultural water efficiency and resilience were discussed. • Policy implications linked to the agricultural water resources management were proposed. [ABSTRACT FROM AUTHOR]

Based on the data of 59 prefecture-level cities in the Yellow River Basin from 2011 to 2019, this paper uses the Slack Based Measure-Global Malmquist Luenberger (SBM-GML) model to measure green total factor productivity (GTFP) of the cities. Under the space–time concept of the Basin, heterogeneity analysis of the upper, middle and lower reaches of the Yellow River Basin is conducted. On this basis, a panel Tobit model is constructed to analyze the impact of environmental regulation on GTFP in the whole basin, upstream region, middle region and downstream region. The results show that the intensity of environmental regulation in the Yellow River Basin increases gradually, which is the highest in the lower reaches, followed by the middle reaches; spatially, the intensity of environmental regulation shows a certain aggregation trend. The green economic growth is realized in the whole basin, and the green technology progress effect is the driving factor of GTFP. The GTFP distribution in the upstream region is relatively concentrated, showing a slow upward trend. The distribution of GTFP in the middle reaches is discrete, and the annual difference is large. In the downstream region, it shows a trend of decline first and then increase. Environmental regulation promotes GTFP in the whole basin, upper, middle and lower reaches, accompanied by certain spatial differences. The Yellow River Basin breaks through the cost effect brought by environmental regulation and triggers technological innovation, thereby enhancing GTFP; the "Porter hypothesis" has been verified in the Yellow River Basin. [ABSTRACT FROM AUTHOR]