Search Results (136)

This study turns to W.E.B. Du Bois’ late-career works of fiction for insights about the importance of Historically Black Colleges and Universities (HBCUs), especially Black public Land-Grant universities in promoting racial justice in the United States. Commentators often argue that Du Bois’ early career endorsement of the emancipatory power of liberal education and social science research was later abandoned in favor of political activism. The present study challenges this assumption by demonstrating that an important, but generally underappreciated, source of continuity in Du Bois’ thoughts on education was his belief that German-inspired social science research could be a means to combat racial injustice in America. In his major work of fiction, the historical novels The Black Flame Trilogy, Du Bois expounded the positive role Black public universities, and their Presidents have historically played in what he called the “racial uplift” of African American people. Du Bois focuses on the impact of the Second Morrill Act of 1890, which established the legal framework for the system of Black Land-Grant universities and colleges, and which he believed provided the institutional foundations for social science research led primarily but not exclusively by Black scholars in projects that center Black experiences. I conclude with reflections on how Du Bois’ literary representation of the importance of historically Black public universities sheds light on current concerns about state coercion and systematic underfunding of Black Land-Grant Universities. Full article

Decades of cultivation and the often exclusive use of mineral fertilisers as a substitute for organic inputs have reduced the soil organic carbon (SOC) content of agricultural soils, meaning they now represent a potential sink for carbon sequestration to mitigate climate change and improve soil function. As well as being a legacy of management, SOC will also be dependent on local scale climate, topography, and soil properties; accounting for this local context is important when benchmarking fields and quantifying the potential for additional carbon sequestration. We developed a landscape-scale methodology, using a handheld infrared device, for baselining SOC stocks in the top 30 cm across a 45,000 ha farm cluster in the UK. The cluster is exploring opportunities for landscape-scale environmental improvement with a focus on natural flood protection and water pollution reduction through conversion of arable land to permanent grassland. We used the baseline data to estimate additional benefits of arable reversion for soil carbon sequestration. Because all the farms in the cluster share the same pedoclimatic conditions, variance in SOC at the field scale could be confidently attributed to differences in soil type and land use. Average SOC stocks in arable and permanent pasture fields were 103.9 and 140.3 Mg C ha⁻¹, respectively. Variance in %SOC was modelled using soil series, sample depth, land use, and clay content, and fields were benchmarked based on deviation from the expected value. The fields with the largest SOC stocks were identified and used as references to predict future potential sequestration. The conversion of arable land to permanent pasture resulted in a predicted average uplift in SOC of 55.0 Mg C ha⁻¹. Our landscape-scale methodology provides robust evidence on current and future carbon stocks for public subsidy schemes and natural capital markets that account for local constraints and opportunities. Full article

Large-scale linear water diversion infrastructures are highly susceptible to ground deformation induced by groundwater extraction, mining activities, and geological instability, posing potential risks to long-term operational safety. However, conventional SBAS-InSAR monitoring of ultra-long linear infrastructures is often constrained by extensive data volumes, computational burden, and uncertainty associated with empirical buffer selection. To address these issues, this study proposes a practical buffer optimization framework for deformation monitoring along the Middle Route Project (MRP) of the South-to-North Water Diversion Project (SNWDP), China. Using Sentinel-1A SAR images acquired from 2023 to 2024, multiple buffer scales were comparatively evaluated by jointly considering deformation inversion accuracy against leveling measurements and computational efficiency. The results indicate that a 5 km buffer achieves the optimal balance between monitoring reliability and processing efficiency. Validation against first-order leveling benchmarks shows high consistency, with an RMSE of 2.54 mm and an MAE of 2.08 mm. Spatial-temporal analysis reveals significant deformation heterogeneity along the MRP. Severe land subsidence was detected in the Tianjin section due to intensive groundwater exploitation, while localized uplift was observed in parts of Hebei Province, likely associated with groundwater recovery. In addition, pronounced subsidence related to mining activities was identified in Yuzhou, Henan Province. The proposed workflow provides a practical reference for deformation monitoring of large-scale linear water diversion infrastructures and demonstrates the potential applicability of buffer optimization strategies for similar long-distance engineering projects. Full article

Marine incursions can profoundly alter biological input and environmental conditions in transitional sedimentary basins, yet their ecological effects remain insufficiently understood in the northern Central Myanmar Basin (CMB). Here, we investigate Upper Cretaceous to Eocene mudrocks from the northern CMB using integrated organic biomarker and elemental geochemical analyses to reconstruct biological precursors, depositional environments, and ecosystem responses during seawater incursions. The biomarker assemblages, including n-alkanes, isoprenoids, tricyclic terpanes, and C₂₇–C₂₉ regular steranes, indicate persistent mixed inputs of marine algal organic matter and terrestrial higher-plant debris. In particular, the upward increase in C₂₉ steranes from the Upper Cretaceous to the Eocene suggests a progressive strengthening of terrestrial input through time. Elemental proxies, including Sr/Ba, Th/U, Y/Ho, (Zn + Ni)/(Ga × 5), Sr/Cu, Rb/Sr, and V/(V + Ni), indicate that deposition occurred under marine-influenced, brackish to locally saline, warm–humid, and predominantly weakly reducing to reducing conditions. We interpret these patterns as evidence that marine incursions reorganized habitat conditions and biological input in a near-equatorial transitional ecosystem. The increasing contribution of terrestrial biomass was likely linked to the progressive uplift and exhumation of the Indo-Burman Ranges, which expanded exposed land area and enhanced the supply of land-derived organic matter to the basin. These results provide a biomarker-based perspective on how marine incursions and paleogeographic reorganization jointly shaped ecosystem dynamics and organic-matter preservation in the northern CMB. Full article

Land subsidence is an important challenge faced by coastal cities under rapid urban development. This study focuses on the Haikou–Laocheng area and conducts time-series monitoring of land subsidence using PS-InSAR and SBAS-InSAR based on 42 Sentinel-1 SAR scenes acquired from April 2023 to April 2025, thereby deriving the spatial distribution of cumulative subsidence rates and the evolution patterns of multi-temporal cumulative subsidence. Because only ascending-orbit Sentinel-1 data were used, the reported deformation values are vertical-projected estimates converted from line-of-sight (LOS) displacement under the assumption that horizontal motion is negligible. The reliability of the monitoring results is evaluated through cross-validation between the two methods, assessing their inter-method consistency. The results indicate that the study area is dominated by slight subsidence, with vertical-projected subsidence rates mainly ranging from −6 to 3.7 mm/y, while a few uplift points are locally observed, forming an overall “stable with localized anomalies” deformation pattern. PS-InSAR and SBAS-InSAR show good consistency in overall trends, and both identify a pronounced subsidence bowl in the southwestern part of the study area, where the peak vertical-projected subsidence rates reach −25.1 mm/y and −35.1 mm/y, respectively, with outward banded attenuation. The results suggest that land subsidence in the study area is influenced by both natural factors and human activities. Specifically, rainfall shows a non-synchronous, stage-wise modulation relationship with subsidence evolution, and most high-subsidence zones are distributed in impervious surfaces such as built-up land and transportation corridors, or in low-elevation areas such as farmland. In terms of geological factors, thick, highly compressible soft soils are the primary geological control on the continued development of subsidence. These findings can provide scientific references for the prevention and control of abnormal subsidence and for urban planning and development in the Haikou–Laocheng area. The strengthened discussion clarifies the research gap, planning significance, and limitations of applying dual time-series InSAR in a data-scarce tropical coastal soft-soil setting. Full article

Vertical land motion in urban areas is a critical manifestation of groundwater, directly affecting infrastructure stability and groundwater sustainability. While land subsidence caused by groundwater extraction has been widely investigated, the opposite process—surface uplift induced by groundwater recovery—remains poorly documented or understood, particularly regarding its hydrological mechanisms and potential hazards. Here, we integrate InSAR time-series analysis of Sentinel-1 imagery (2017–2025) with groundwater well records to quantify the spatial–temporal characteristics of uplift in Xi’an, China, and to evaluate its hydrogeological drivers. Results reveal a persistent surface uplift zone south of the ancient city in Xi’an, with rates up to 20 mm/yr. The uplift correlates closely with rising groundwater levels in the shallow confined aquifer, indicating a strong coupling between aquifer recharge and surface uplift. Calculated storage coefficients and hydraulic diffusivity values highlight marked spatial variations, constrained by some ground fissures that act as both mechanical discontinuities and hydrological barriers controlling pressure diffusion. Time-series analysis further identifies the eastward propagation of subsidence-to-uplift reversal in Yuhuazhai, an urban village with groundwater injection, which is used to quantify the diffusivity coefficients. Field investigations show that rapid groundwater rebound can lead to uplift-related hazards, such as basement seepage, underscoring that surface uplift must be considered alongside subsidence in urban water management. Full article

This study applies Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) to investigate surface deformation dynamics in the hyper-arid Eastern Province of Saudi Arabia, with emphasis on quantifying sand dune migration and identifying areas susceptible to wind erosion. Utilizing Sentinel-1 SAR data and the MintPy toolbox, ground deformation was quantified with millimeter-scale precision. Results reveal significant subsidence, up to 15 cm/year in landfills, linked to waste compaction and groundwater depletion. Localized uplift of ~4 cm/year on northern peripheries is directly attributed to aeolian sand accumulation from seasonal Shamal winds, providing quantitative evidence of dune migration. While direct measurement of wind erosion (net deflation) remains challenging due to the dominance of depositional signals and the spatial heterogeneity of erosion processes, areas of potential erosion are inferred from negative displacement patterns outside landfill zones and from coherence characteristics indicative of surface instability. The integration of SBAS-InSAR with GPS and ERA5 wind reanalysis resolves the combined influence of aeolian deposition, hydrogeological changes, and anthropogenic activity, offering insights into both components of aeolian dynamics and a replicable model for sustainable land management in arid environments. Full article

The Persistent Scatterers InSAR (PSInSAR) technology, which utilizes pixels with stable phases to extract ground deformation, is an effective tool for large-scale, long-period surface monitoring applications. It has been widely applied to land subsidence monitoring, earthquake research, and infrastructure risk management. Furthermore, some studies have successfully employed this method to monitor the progressive motion of creeping in landslide areas. However, these regions containing active landslides are usually covered by canopy layers, which cause low coherence in InSAR processing and reduce the number of stable pixels, thereby preventing long-term period monitoring in those areas. In this study, the supervised deep learning model, U-Net, based on a convolutional neural network, is applied to the differential InSAR dataset acquired from Sentinel-1 to improve persistent scatterer selection. A well-processed PSInSAR result, utilizing 55 Sentinel-1 images acquired from 5 November 2014 to 19 December 2017, is introduced as a dataset for model training. The pixel-based Persistent Scatterer (PS) labels used for model training are identified using the StaMPS software. The model is designed to identify the distributed scatterer (iDS) index using a single pair of SAR images. As a result, more iDS pixels can be obtained from a single interferogram, indicating a significant improvement over the StaMPS algorithm. The line-of-sight velocity and time series of PS pixels from the model prediction show a long-term uplift on the upper slope, which represents downslope sliding in the target area. Furthermore, some iDS pixels exhibit a seasonal deformation on the lower part of the slope. The capability for these additional deformation analyses underscores the potential of this new deep-learning-based approach. Full article

The demand for food has increased due to the world’s expanding population, which has also put pressure on vital resources like water, land, and nutrients. Therefore, in order to guarantee food security, it is imperative to establish alternative, sustainable, and dependable strategies. In recent decades, researchers have developed novel food production methods that collectively enhance the efficiency and sustainability of food systems. Among these, aquaponics stands out as an advanced and eco-friendly agricultural technology that integrates aquaculture and hydroponics. In this system, fish waste from the aquaculture unit is utilized as a nutrient medium in the hydroponic subsystem to grow edible plants. This review aims to assess the potential of aquaponics to produce high-quality fruits, vegetables, and fish while minimizing environmental impacts without relying on chemical fertilizers. The study focuses on system design, nutrient cycling, and productivity parameters to assess its feasibility under Potohar conditions. The expected outcome is to demonstrate that aquaponics can enhance food quality, conserve resources, and uplift the socio-economic status of farming communities by alleviating poverty. Full article

Land subsidence (LS) is a major global geo-environmental issue that profoundly affects the suitability and safety of land use planning (LUP). However, existing LUP systems generally neglect the dynamic evolution of LS and lack a systematic framework for assessing conflicts between land use and subsidence. To address this gap, this study develops an integrated evaluation framework that combines SBAS-InSAR, GeoDetector, and a spatial conflict detection model. A total of 166 Sentinel-1A images acquired from 2017 to 2024 were processed using SBAS-InSAR to derive the spatiotemporal characteristics of LS. GeoDetector was subsequently applied to identify the dominant driving factors and their interactions. A sensitivity classification scheme for current land use (CLU) and LUP types with respect to LS hazards was then developed, and a spatial conflict detection model was constructed to delineate conflict zones and quantify conflict intensity. Using Huainan City as a case study, the results show the following: (1) from 2017 to 2024, LS was generally characterized by slight or negligible subsidence, with severe subsidence mainly concentrated in coal mining areas; ongoing and recently suspended mines exhibited pronounced LS, whereas early-closed and unmined areas showed an overall uplift trend. (2) LS in Huainan was primarily driven by soil type, annual rainfall, and mining activities, and two-factor interactions generally exhibited enhancement effects. (3) Compared with CLU, LUP has, to some extent, incorporated LS risk considerations and implemented corresponding mitigation measures, although certain areas still insufficiently account for LS risks. (4) The proposed framework demonstrates strong rationality and applicability in LS monitoring, driving factor identification, and spatial conflict assessment, providing scientific support for LS risk management and land use spatial optimization. Full article

The Tinjar–West Baram Fault in the southern South China Sea is a major NW-trending strike-slip fault that has remained tectonically active since the Oligocene. It forms a key structural boundary between the Zengmu, Beikang, and Nansha Trough basins. Multi-phase strike-slip movements have strongly controlled sediment provenance dispersal pathways, and reservoir development in the Zengmu Basin, yet the sedimentary response to these tectonic processes remains poorly understood. This study integrates 2D seismic profiles to analyze the fault geometry, kinematics, and impact on deep-water sedimentary systems. Results indicate that Oligocene right-lateral motion directed sediment supply from the southwest, mainly sourced from Kalimantan, forming fluvial–deltaic systems with depocenters in the southern basin. Since the Late Miocene, a transition to left-lateral motion reoriented sediment provenance toward the southeast, leading to delta-front complexes and northward migration of depocenters. Strike-slip activity deformation enhanced rock fragmentation and sediment supply, producing fan delta, fluvial, and shallow lacustrine facies near the fault. Associated uplift and subsidence induced relative sea-level fluctuations, resulting in alternating transgressive–regressive sequences. From the Late Eocene to Miocene, the basin evolved from a land–sea transitional system to a deltaic–carbonate complex controlled by the paleo-Sunda River. During the Pliocene–Quaternary, sedimentation was dominated by shallow-marine shelf and semi-deep-marine deposits. Fault-related fracturing significantly enhanced porosity and permeability, creating favorable conditions for hydrocarbon migration and entrapment in both sandstone and carbonate reservoirs. These findings demonstrate a strong coupling between strike-slip fault activity and sedimentary system evolution, providing important insights into sedimentary processes and hydrocarbon potential in strike-slip fault-bounded basins globally. Full article

Urbanization in mountainous valley regions is constrained by rigid topography, generating complex correlations between spatial growth and ecological security. The coupling between urban expansion and landscape ecological risk (ERI) was evaluated for six representative valley cities in western China from 1985 to 2023. Annual land-cover data (CLCD) and fine-scale terrain models were integrated with expansion metrics, slope gradient analysis, and spatial statistics to identify growth trajectories and risk reorganization. Urban growth shifted from edge expansion to leapfrog development as valley floors became saturated. Two vertical trajectories emerged: a low-slope lock-in pattern (e.g., Lanzhou) where development remains largely on slopes < 6° and an uplift towards mid-slopes pattern (e.g., Chongqing), where expansion increasingly occurs on 6–25° terrain. ERI correspondingly showed three spatial typologies: valley contrast, heterogeneous mosaic, and high-risk background dominance. Although ERI generally declined, reflecting structural hardening with rising built-up land shares, the spatial clustering of risk remained stable. GeoDetector results indicate that terrain sets a baseline for ERI differentiation, but its explanatory power varies across cities and is often surpassed by land-cover composition. These findings support differentiated governance, requiring strict controls on slope disturbance in uplift cities and prioritizing corridor connectivity in lock-in cities. Full article

Understanding landform evolution is essential for assessing how terrain responds to geomorphic drivers such as weathering, fluvial erosion, hillslope processes, and tectonic uplift. This is particularly important in applications such as constructed post-mining landform rehabilitation, where predicting long-term erosional stability is vital for sustainable closure planning. In addition to long-term average erosion rates, the spatial patterns of gullies, rills, and channels are critical for assessing landform stability. This review examines Digital Elevation Model (DEM)—driven, process-based Landform Evolution Models (LEMs), with a primary focus on SIBERIA, CAESAR-Lisflood, and SSSPAM, which are widely used to evaluate the erosional behaviour of constructed post-mining landforms, each with distinct characteristics. These models are systematically compared in terms of input requirements, process representations, parameterisation, and predictive capabilities. Recent advances in high-spatial resolution DEMs (e.g., LiDAR, SRTM), along with digital soil and rainfall databases and satellite-derived vegetation indices, have improved the parameterisation of erosion, hydrological, and sediment-transport processes of the LEMs. A brief comparative case study is presented to demonstrate how these LEMs simulate 1000-year erosional behaviour along a linear hillslope. This review synthesises the current capabilities and limitations of DEM-driven LEMs, providing guidance for researchers, land managers, and practitioners in selecting appropriate models to support sustainable post-mining landform management, as well as outlining potential future advancements. Full article

Despite complex geological conditions and limited exploration activity, the South Yellow Sea Basin has not yet yielded a commercial hydrocarbon discovery. Recent studies indicate substantial hydrocarbon potential within the Upper Sinian–Lower Silurian strata; however, the mechanisms controlling hydrocarbon accumulation in these sequences remain poorly understood. In this study, outcrop, drilling, organic geochemical, and seismic data from the Yangtze Plate are integrated using a land–sea comparison approach to evaluate petroleum geological conditions, identify key controlling factors, and predict hydrocarbon accumulation in the Upper Sinian–Lower Silurian sequences of the Laoshan Uplift. The results indicate that the Upper Sinian–Lower Silurian strata possess favorable petroleum geological conditions, including two effective source–reservoir–seal assemblages. Key controls on deep hydrocarbon accumulation include high-quality Lower Cambrian source rocks, early development of the Laoshan paleo-uplift, structural stable zones, and Lower Silurian detachment layers. Three hydrocarbon accumulation evolution models are proposed: (1) early stage lateral hydrocarbon supply from adjacent depressions, (2) early stage lower-source–upper-reservoir charging, and (3) late-stage deep-burial cracking with structural adjustment. These findings provide important guidance for deep hydrocarbon exploration the Upper Sinian–Lower Silurian sequences of the Laoshan Uplift in the South Yellow Sea Basin. Full article

The Metaponto coastal plain (Ionian margin, Southern Italy) records the Late Pleistocene–Holocene evolution of a foredeep coastal system shaped by relative sea-level change, vertical land motion, and compaction. We analyze a 22 m continuous core (Meta 1) using lithofacies logging, grain size statistics and cumulative curves, multivariate analysis of grain size distributions (PCA and k-means clustering), and three AMS 14C ages, and we compare the record with a nearby borehole (MSB) and a global eustatic curve. Four depositional units document a shift from lower-shoreface–offshore deposition to lagoon–barrier/aeolian systems, culminating in late Holocene near-surface progradation. Textural end members (mud-rich offshore/lagoonal, traction-dominated, and sand-rich) are coherent across classical parameters, Visher-type curves, PCA, and k-means clusters. Depth–age comparisons suggest net uplift during the Late Glacial, followed by near-present relative sea level and a Late Holocene onset of modest net subsidence; a compaction contribution is plausible but unquantified. Subsidence/uplift rates therefore remain upper-bound estimates owing to sparse chronological control and the lack of glacio-isostatic and compaction modeling. Together with the MSB emerged-beach tie-point, the record constrains shoreline position and progradation. The inferred Mid- to Late-Holocene stabilization and progradational trends are consistent with other Italian and wider Mediterranean coastal plains. Additional dating and quantitative paleoecological proxies (e.g., foraminifera/ostracods/molluscs) are key to independently constrain salinity and water-depth changes and to refine the partitioning between subsidence and compaction. Full article