Search Results (18,233)

Trichopria drosophilae is a globally distributed pupal parasitoid that targets various species within the Drosophilidae family, including the invasive Drosophila suzukii. The mass rearing of T. drosophilae is a crucial step in ensuring their successful application for field D. suzukii control. The pupae of Drosophila melanogaster are currently used as a host for the mass rearing of T. drosophilae. After irradiation, the immune system function of Drosophila pupae was weakened, leading to an increase in the parasitism efficiency of the T. drosophilae. Our results showed that irradiated pupae had a significant impact on the parasitism rate, offspring eclosion rate, offspring number, and female body size of F1 T. drosophilae, all of which were significantly lower than those in the normal group. However, there was no significant difference in the parasitism rate, body size, offspring eclosion rate, offspring number, or offspring sex ratio between F2 T. drosophilae emerging from treated or untreated Drosophila pupae. Compared with F2, F1 had a significantly higher net reproductive rate (R₀), mean generation time (T), and doubling time (DT), while the intrinsic rate of increase (r) was significantly lower. Using irradiated D. melanogaster pupae provides an efficient method for the mass rearing of T. drosophilae and offers valuable insights into its potential effectiveness in field D. suzukii control. Full article

The prediction of structural fractures in concealed coal-bearing strata has always been a complex problem. The purpose of this study was to clarify the tectonic evolution of the study area, i.e., the Tucheng syncline, since the coal-forming period and to predict the development of structural fractures. The tectonic evolution of the study area was divided into three stages using regional tectonic analysis. The paleotectonic stress field of the study area was reconstructed through the field investigation, statistics, and analysis of joints. Based on the tectonic deformation analysis, numerical simulation was used to reveal the stress field characteristics of different tectonic deformation stages, and combined with the Mohr–Coulomb criterion, the degree of structural fracture development in the target layers (No.17^# coal seam) of the study area was predicted. This study concludes the following: (1) The study area underwent two tectonic deformations during the Yanshanian period, transitioning from an ellipsoidal columnar shape to a semi-ellipsoidal and stereotyped form, forming a superimposed short-axis syncline, and then tilting southeastward as a whole, and was locally cut by faults during the Himalayan period. (2) The distribution characteristics of the stress field in different tectonic stages vary. The stress concentration zones in the first and second stages have a more obvious symmetry, and the present-day stress concentration zone is located in the center of the syncline basin. (3) The superimposed rock fracture indices are larger in the edge zone parallel to the long axis of the syncline and at the bottom of the syncline, which also indicates a higher degree of structural fracture development at the corresponding locations. Full article

The exploration of the Fengcheng Formation has revealed the characteristic orderly coexistence of conventional reservoirs, tight reservoirs, and shale reservoirs, constituting a full spectrum of reservoir types, and is important for unconventional oil and gas exploration and development. Affected by frequent volcanic tectonic movement, hot and dry paleoclimate, and the close provenance supply distance, unique saline–alkaline lacustrine deposits formed during the depositional period of the Fengcheng Formation. The lithologies of the Fengcheng Formation are highly diverse, with endogenous rocks, volcanic rocks, terrigenous debris, and mixed rocks overlapping and forming vertical reservoir changes ranging from meters to centimeters. Owing to the complexity of rock types and scarcity of rock samples, the evaluation of reservoirs in mixed-rock has progressed slowly. Hence, we aimed to evaluate the characteristics of Fengcheng Formation shale oil reservoirs. Centimeter-level core characteristics were analyzed based on the lithological change and structural characteristics. To investigate the lithofacies of the Fengcheng Formation in the Mahu Sag and factors affecting reservoir development, high-frequency sedimentary structures were analyzed using sub-bio-buffering electron microscopy, energy spectrum testing, and fluorescence analysis. The results showed that the shale oil reservoirs in the study area can be divided into four categories: glutenite, volcanic rock, mixed rock, and endogenous rock. The reservoir capacity has improved and can be divided into eight subcategories. Mixed-rock reservoirs can be further divided into four subcategories based on differences in structure and composition. Differences in the bedding and dolomite content are the main factors controlling the differences in the physical properties of this type of reservoir. This study provides a reference for the classification and characteristic study of shale oil reservoirs in saline–alkali lake basins. Full article

Land-use transition has diverse influences on habitat quality. At present, land-use patterns and habitat quality in the ecologically fragile Yellow River Basin are undergoing significant change. However, the relationship between land-use transition and habitat quality and the driving factors of habitat quality dynamics across the whole basin remain unclear. In this study, we utilized a land-use transition matrix and an InVEST model to analyze the dynamics of land use, habitat quality, and the relationship between the two in the Yellow River Basin from 2005 to 2020. The driving factors of habitat quality dynamics were explored with a spatial econometric model. The results showed the following: (1) The areas of farmland and grassland accounted for more than 70%, but decreased by 14,600 km² and 2500 km², respectively. The areas of forest and construction land increased by 1800 km² and 16,900 km², respectively. (2) The habitat quality showed a trend of decrease-then-increase. The areas of low value (0–0.2) were the largest, accounting for about 50% of the total area; the regions of relatively high (0.6–0.8) and high value (0.8–1) were small and scattered in the mountainous forest area, accounting for about 10%. (3) The habitat quality was the lowest in the land categorized as transitioning to construction, and highest in unchanged forest and in the land characterized as transitioning to forest. The coupling coordination degree of land-use degree and habitat quality showed a steady upward trend. (4) The growth rate in the value added by secondary industries, GDP per capita, population density, ecological-protection policy score, average annual temperature, and average annual precipitation were the primary factors affecting habitat quality. This study fills the gap in the analysis of the relationship between land-use transition and habitat quality across the whole Yellow River Basin; the work assists in the understanding of the ecological effects of land-use transition in the region and provides suggestions for the development of other densely populated and ecologically fragile areas. Full article

Water quality prediction serves as an important foundation for risk control and the proactive management of the aquatic environment, and the Long Short-Term Memory (LSTM) network has gained recognition as an effective approach for achieving high-precision water quality predictions. However, despite its potential, there is a significant gap in the literature regarding the confidence analysis of its prediction accuracy and the underlying causes of variability across different water quality indicators and basins. To address this gap, the present study introduces a novel confidence evaluation method to systematically assess the performance of LSTM in predicting key water quality parameters, including ammonia nitrogen (AN), biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO), hydrogen ion concentration (pH), and total phosphorus (TP). This evaluation was conducted across three basins with distinct geographical, climatic, and water quality conditions: the Huangshui River Basin (HSB), the Haihe River Basin (HRB), and the Yangtze River Basin (YRB). The results of the confidence evaluation revealed that LSTM exhibited higher credibility in the Haihe River Basin compared to the Yangtze River Basin. Additionally, LSTM demonstrated greater accuracy and stability in predicting total phosphorus (TP) compared to other water quality indicators in both basins, with median NSE values of 0.71 in the HRB and 0.73 in the YRB. Additionally, the research demonstrated a linear relationship between the ability of LSTM models to predict the water quality and temporal autocorrelation as well as the cross-correlation coefficients of the water quality parameters. The coefficients of determination (R²) ranged from 0.59 to 0.85, with values of 0.59 and 0.79 for the YRB and 0.85 and 0.80 for the HRB, respectively. This finding underscores the importance of considering these correlation metrics when evaluating the reliability of LSTM-based predictions. Full article

Rainfall datasets from the Uganda National Meteorological Authority (UNMA) for 1981–2017 and two reanalysis datasets (Climate Hazards Group Infrared Precipitation with Stations data (CHIRPS) and Tropical Applications of Meteorology using Satellite data (TAMSAT) were used to compute drought and flood tendencies from 1981 to 2017. The cumulative departure index (CDI) and rainfall anomaly index (RAI) were computed to show drought and flood tendencies in the region. Meanwhile, dry days (DD) and wet days (WD) were computed based on the definition as a day of the season with rainfall amounts less than 1.0 mm and greater than 1.0 mm, respectively. The CDI graphics indicated below-average rainfall during 1981–1987 and relatively wetter conditions during 1989–1995 for all stations in the region. Generally, seasonal rainfall declined over the first 27 years but an increasing trend in both MAM (March–April–May) and SOND (September–October–November–December) was observed in most stations during 2006–2017. The highly variable seasonal rainfall in the region is expected to impact the livelihoods of the communities. This study recommends that the use of tailor-made weather and climate information for planning economic development programs such as agriculture will play a critical role in improving the livelihood of the communities in the region. Full article

For lacustrine shale oil and gas reservoirs with coexisting hydrocarbon fluid properties, evaluating the adsorption capacity of shale is of significant importance for the exploration of lacustrine shale oil and gas. Taking the lacustrine shale from the Jurassic Lianggaoshan Formation in the northern Sichuan Basin as an example, this study conducted pyrolysis, scanning electron microscopy (SEM), and high-pressure methane isotherm adsorption tests to investigate the methane adsorption capacity of lacustrine shale and its controlling factors. The research findings are as follows: (1) The organic matter content in the study area’s lacustrine shale is moderate, with organic types ranging from II to III, and it is within the oil generation window stage. The mineral composition exhibits characteristics of high clay and low silica content; (2) Both the TOC (total organic carbon) and clay minerals promote the methane adsorption capacity of lacustrine shale; however, due to the overall moderate–low TOC levels, the storage space is primarily composed of inorganic pores; (3) A high clay mineral content provides more surface area, becoming a primary factor influencing shale adsorption capacity. This indicates that semi-deep lake deposits also possess exploration potential. Full article

Ecological restoration projects in the Loess Plateau have significantly altered the underlying surface, which has profoundly affected the regional water cycle. In the context of the ongoing climate change, quantitatively identifying the factors influencing runoff changes and simulating runoff responses to various land management policies are essential for achieving sustainable development in arid/semi-arid regions. Daily hydrological and meteorological data from 1981 to 2020 along with the SWAT model were employed to analyze the attribution of runoff changes in the Yanhe River basin and simulate runoff responses under different climate and land-use scenarios. The results show the following: (1) the improvement of the underlying surface conditions appeared to be the leading factor of runoff retention, with a contribution of 81.21%, while the influence of climate change on runoff was minimal; (2) woodland generally exhibited superior performance in retaining runoff compared to grassland under diverse climate conditions; (3) converting farmland on slopes between 15 and 25 degrees into woodland and farmland on slopes exceeding 25 degrees into grassland demonstrated to be a more effective approach to controlling soil erosion; (4) it is recommended that a balance between water resource utilization and the extent of afforestation should be considered concurrently in future ecological restoration. Full article

Southeastern Sichuan has witnessed intensified seismic swarm activity since 2016, including events exceeding historical peak ground accelerations. This study integrates moment tensor solutions, stress field inversion, and Mohr–Coulomb analysis to investigate the interplay between tectonic processes and shale gas extraction in driving seismicity. Full-waveform moment tensor inversions of 118 earthquakes (M ≥ 3.5) reveal predominant double-couple mechanisms (62% with DC > 70%), with minor non-double-couple components linked to fluid-induced volume contraction. Stress field inversions demonstrate spatial heterogeneity: Region A (south) exhibits a counterclockwise-rotated maximum horizontal stress direction compared to Region B (north), which aligns with the regional NW-SE tectonic compression. Mohr’s circle analysis highlights distinct failure regimes—40% of the events in Region A fall below the failure threshold (pore-pressure-influenced), while 60% in Region B exceed it (stress-dominated). These findings underscore the combined roles of tectonic inheritance (NE-SW basement faults) and anthropogenic perturbations (fluid injection) in modulating seismic hazards. Full article

In the Southeastern Ordos Basin, the Chang 2 low-permeability sandstone reservoir of the Triassic Yanchang Formation is a typical heterogeneous reservoir. Quantitatively characterizing and analyzing its complex pore throat structure has become crucial for enhancing storage and production in the study area. The pore throat structure is a key factor influencing reservoir properties. To achieve this, a comprehensive suite of analytical techniques was employed, including cast thin section (CTS), scanning electron microscopy (SEM), cathodoluminescence (CL), X-ray diffraction (XRD), and mercury intrusion capillary pressure (MICP). This study quantitatively characterizes the pore size distribution of reservoirs in the Southeast Ordos Basin. Based on fractal theory, it clarifies the complexity of the pore throat structure and the degree of microscopic heterogeneity at different scales. Finally, this study reveals the correlation between fractal dimensions and storage and permeability capacities and analyzes the controlling factors. The findings indicate that the predominant lithotype in the study area is fine-grained feldspar sandstone, which develops pore types such as intergranular pores, dissolution pores, and microfractures. Based on the shapes of mercury injection curves and pore throat structural parameters, and in conjunction with SEM images, the samples are categorized into three types. Type I samples exhibit good pore throat connectivity and are characterized by a lattice model. Type II samples are characterized by a tubular pore throat model. Type III samples have poor pore throat connectivity and are characterized by an isolated model. The pore throat network of low-permeability sandstone is primarily composed of micropores (pore throat radius r < 0.1 μm), mesopores (0.1 < r < 1.0 μm), and macropores (r > 1.0 μm). The complexity of the reservoir pore throat structure was quantitatively characterized by fractal theory. The total fractal dimension (D) of all the samples is between 2 and 3, which indicates that the reservoir has capillary fractal characteristics. The average fractal dimension of micropores (D1) is 2.57, while that for mesopores (D2) and macropores (D3) is slightly higher, at an average of 2.68. This suggests that micropores have higher self-similarity and homogeneity. The fractal dimensions D1, D2, and D3 of the three types of reservoirs all exhibit a negative correlation with porosity and permeability. This shows that the more complex the pore throat structure is, the worse the storage and seepage capacity of the reservoir. For type I samples, the correlation of D3 with pore throat structural parameters such as entry pressure, skewness, and maximum mercury saturation is better than that of D2 and D1. For type II and type III samples, D2 shows a significant correlation with pore throat structural parameters. This indicates that the heterogeneity and complexity of mesopores are key factors influencing the pore throat structure of poor-quality reservoirs. Different mineral compositions have varying effects on the fractal characteristics of pore structures. Quartz, feldspar, and clay exert both negative and positive dual impacts on reservoir quality by altering the pore throat structure and the diagenetic processes. The mineral content exhibits a complex quadratic relationship with the fractal dimension. Moreover, micropores are more significantly influenced by the mineral content. The study of the relationship between the fractal dimension and physical properties, pore throat structural parameters, and mineral composition can improve the understanding of the reservoir quality of low-permeability reservoirs. This provides a theoretical basis for exploration and improving the recovery rate in the study area. Full article

Tuffaceous fillings are a significant component of the Permian Kuishan sandstone in the North China Platform, and their complex diagenetic processes have a notable impact on the development of clastic rock reservoirs. This study, based on microscopic analysis of reservoirs and combined with quantitative analytical techniques such as electron probe microanalysis, homogenization temperatures of fluid inclusions, micro-area carbon-oxygen isotope analysis, and laser Raman spectroscopy, investigates the influence of tuffaceous interstitial material dissolution on reservoir development in the Permian Kuishan sandstone of the Gaoqing buried hill in the Jiyang Depression, Bohai Bay Basin. The results indicate that the dissolution intensity of tuffaceous interstitial materials can be classified into three levels: strong, moderate, and weak. In the strong dissolution zone, associated fractures and dissolution pores significantly contribute to reservoir porosity, with a positive correlation between dissolution plane porosity and total plane porosity. The reservoir space is characterized by a network of dissolution pores and fractures. The moderate dissolution zone is marked by the development of authigenic quartz, feldspar, and clay minerals, which do not effectively enhance porosity and permeability. The weak dissolution zone contains well-preserved volcanic glass shards, crystal fragments, and clay minerals, representing non-reservoir development sections. Lithology, sedimentary facies, diagenesis, and fractures collectively control the quality of the Permian Kuishan sandstone reservoir in the Gaoqing buried hill of the Jiyang Depression, Bohai Bay Basin. The advantageous zones for reservoir development in this area can be effectively predicted using thickness maps of the Kuishan sandstone, planar distribution maps of sedimentary facies, and fracture prediction maps derived from ant-tracking and coherence algorithms. Full article

In the 21st century, the adoption of solar energy has witnessed significant growth, driven by the increased use of ground-mounted photovoltaic (GPV) systems, recognized as solar farms, which have emerged as major players in this sector. Nevertheless, their extensive land utilization may impact local ecosystem services (ESSs), especially those related to water resources. In the context of the water–energy–food–ecosystem (WEFE) nexus, it becomes vital to investigate how solar park construction will impact water-related ESSs. This paper developed a framework that assesses the effect of constructing a solar park on water-related ecosystem services. We focused on solar farm construction and its interactions with various hydrological cycle components; then, we evaluated the implications for water-related ESSs. This approach encompasses a systematic literature review that identifies the hydrological factors most affected by the construction of solar farms. As a result, thirteen ESSs were selected to be included in an evaluation framework, and a definition of a scoring system of each ESS was defined based on the economic value, a predetermined indicator, or land use and land cover (LULC) properties. The allocation of weighting factors for these scores can be determined based on individual experience and stakeholders. This study presents a DSS-integrated framework to assess the impact of solar park constructions on water-related ecosystem services (ESSs) within the WEFE nexus. The framework was applied to a case study in Darstadt, Bavaria, revealing that, among the water-related ESSs in favor of ground-mounted PV systems (GPVs) compared to traditional agricultural practices, there could be soil erosion and nitrate leaching reduction. The DSS tool enables stakeholders to efficiently evaluate trade-offs between energy production and ecosystem impacts. The findings underscore the potential of integrating renewable energy projects with ecosystem management strategies to promote sustainable land-use practices. Full article

This study investigated the occurrence of fibrous microplastics and natural and artificial cellulose microfibers in the gastrointestinal tracts of Mullus barbatus and Merluccius merluccius specimens from the Adriatic Sea (Central Mediterranean), an important hotspot for marine litter accumulation. Red mullet and European hake were chosen due to their roles as bioindicators of marine pollution in the Mediterranean, and their economic relevance as fishery resources. Microfibers were found in 72% of M. barbatus and 68% of M. merluccius, at levels ranging from 1 to 67 particles/individual. Most of the microfibers extracted were textile fibers that were blue (33.6%), clear (26.1%), and black (20.3%) in color, while the length distribution showed the prevalence of microfibers in the size range of 350–950 µm. This visual identification, corroborated by the micro-FTIR analysis of a sub-sample of microfibers, revealed that natural and artificial cellulose microfibers were more common (80%) than fibrous microplastics. The results confirmed that both of these fish species are susceptible to microfiber ingestion and indicated the high availability of natural and artificial cellulosic fibers in the Adriatic Basin. Despite the increased evidence of microfiber pollution in the marine ecosystem, only a limited number of studies examine natural/artificial microfiber contamination and ingestion by marine biota. Therefore, greater attention should be given to this new type of contaminant, considering its implications in terms of environmental health, food security, and food safety. Full article

The Ruoergai Wetland is the highest and largest plateau peat swamp wetland in the world, providing more than 30% of the water for the upper reaches of the Yellow River. It performs vital regulatory functions in maintaining the quality and stability of the regional ecosystem of the Yellow River Basin. It is of great significance to study the spatial and temporal variability of water conservation services as well as ecological restoration and enhancement strategies at multiple scales. Based on field research, using the InVEST model, this study quantitatively assessed water conservation for a long period at the Ruoergai Wetland, proposing a strategy to improve water conservation capacity. The results showed that both grassland (mainly alpine meadow with Kobresia Willd and Cyperus papyrus) and wetland in the study area exhibited degradation. The proportions of significantly decreased, moderately decreased, slightly decreased areas were 50.64%, 16.81%, 11.64%, respectively. There were also significant changes in water conservation capacity from 2020 to 2023, with strong spatial heterogeneity. Average water conservation per unit area ranged from 52.70 to 211.99 mm/m², with a decreasing trend. However, in the past 10 years, the area of soil erosion decreased by about 4735 km². Although the soil erosion situation has improved to a large extent, there is still increasing soil erosion in some areas. Based on the field investigation, the intrinsic mechanisms of water conservation in alpine wetlands were elaborated, the driving forces behind the changes in water conservation functions were described, and further ecological restoration strategies were proposed from the perspectives of engineering measures, spatial zoning, and industrial structure. Full article

Prediction of the intensity of earthquake-induced motions at the ground surface attracts extensive attention from the geoscience community due to the significant threat it poses to humans and the built environment. Several factors are involved, including earthquake magnitude, epicentral distance, and local soil conditions. The local site effects, such as resonance amplification, topographic focusing, and basin-edge interactions, can significantly influence the amplitude–frequency content and duration of the incoming seismic waves. They are commonly predicted using site effect proxies or applying more sophisticated analytical and numerical models with advanced constitutive stress–strain relationships. The seismic excitation in numerical simulations consists of a set of input ground motions compatible with the seismo-tectonic settings at the studied location and the probability of exceedance of a specific level of ground shaking over a given period. These motions are applied at the base of the considered soil profiles, and their vertical propagation is simulated using linear and nonlinear approaches in time or frequency domains. This paper provides a comprehensive literature review of the major input parameters for site response analyses, evaluates the efficiency of site response proxies, and discusses the significance of accurate modeling approaches for predicting bedrock motion amplification. The important dynamic soil parameters include shear-wave velocity, shear modulus reduction, and damping ratio curves, along with the selection and scaling of earthquake ground motions, the evaluation of site effects through site response proxies, and experimental and numerical analysis, all of which are described in this article. Full article