Zhuang Li

The safe utilization of underground spaces constitutes a critical challenge for densely populated cities, making geosafety risk prevention in underground development a focal point for both academic research and governmental governance. As the pivotal link and ultimate objective in geological safety management, risk prevention facilitates the transition from theoretical research to administrative practice. This study establishes a management-oriented technical framework for geological risk preventive zoning in underground space utilization, addressing the current research gap where zoning methodologies inadequately integrate with governmental decision-making processes due to insufficient consideration of multidimensional attributes from both researcher and administrator perspectives. Taking Xiong’an New Area in China as a case study, the framework employs a tri-level analytical structure, restrictive tier, limiting tier, and influencing tier, with phased weighting methodologies, CRITIC-EWM for objective weighting vs. AHP-FAHP for subjective weighting. The scientifically validated results demonstrate the framework’s feasibility and scalability. Limitations and future research directions are identified to guide subsequent studies in this field.

Land desertification in the Agropastoral ecotone of arid and semi-arid regions poses significant threats to ecological security. Elucidating the geochemical characteristics and provenance of surface sediments is crucial for understanding desertification mechanisms and developing effective sand-control strategies. This study focuses on Kangbao County in the Bashang region of Hebei Province. We systematically collected 57 surface sediment samples from four geomorphic units: low mountains-hills, gently sloping hills, gully depressions, and undulating plains. Major and trace element concentrations were determined using X-ray fluorescence spectroscopy (XRF) and inductively coupled plasma mass spectrometry (ICP-MS). Elemental ratios, principal component analysis (PCA), and Non-metric Multidimensional Scaling (nMDS) were employed to decipher sediment geochemical signatures and provenance, emphasizing geomorphologically controlled source differentiation mechanisms. Key findings are as follows: (1) Geochemical characteristics reveal that sediment elemental enrichment or depletion patterns exhibit fundamental differences depending on the specific bedrock reference. When normalized against felsic versus mafic end-members, elements including Fe₂O₃, MgO, TiO₂, CaO, Cr, Ni, Co, V, Rb, and Ba demonstrate contrasting geochemical behaviors. (2) The sediments originate from a homogenized mixture derived from the weathering of regional bedrock, clearly distinct from the high-maturity aeolian sands of the Hunshandake Sandy Land. (3) The spatial geochemical differentiation of surface sediments follows a two-stage process: the initial formation of a homogenized sediment source from bedrock weathering products, followed by subtle modification through landform-specific geomorphic processes, resulting in weak but systematic geochemical variations across the landscape. Based on these findings, a zonal management strategy is proposed to disrupt the localized sediment cycle by intercepting sources in hilly areas, restoring gully depressions, and blocking aeolian pathways on the plains. This study provides a scientific basis for precise desertification control in Kangbao and supports ecological barrier enhancement for the Beijing–Tianjin–Hebei region.

As a fundamental metric for assessing carbon sequestration, Net Primary Productivity (NPP) and the mechanisms driving its spatiotemporal dynamics constitute a critical research domain within global change science. This research centered on the Huang–Huai–Hai Plain (HHHP), combining 2001–2023 MODIS-NPP data with natural (landform, temperature, precipitation, soil) and socio-economic (population density, GDP density, land use) drivers. Trend analysis, coefficient of variation, and Hurst index were applied to clarify the spatiotemporal evolution of NPP and its future trends, while geographic detectors and structural equation models were used to quantify the contribution of drivers. Key findings: (1) Across the HHHP, the multi-year average NPP ranged between 30.05 and 1019.76 gC·m⁻²·a⁻¹, with higher values found in Shandong and Henan provinces, and lower values concentrated in the northwestern dam-top plateau and central plain regions; 44.11% of the entire region showed a statistically highly significant increasing trend. (2) The overall fluctuation of NPP was low-amplitude, with a stable center of gravity and the standard deviation ellipse retaining a southwest-to-northeast direction. (3) Future changes in NPP exhibited persistence and anti-persistence, with 44.98% of the region being confronted with vegetation degradation risk. (4) NPP variations originated from the synergistic impacts of multiple elements: among individual elements, precipitation, soil type, and elevation had the highest explanatory capacity, while synergistic interactions between two elements notably enhanced the explanatory capacity. (5) Climate variation exerted the strongest influence on NPP (direct coefficient of 0.743), followed by the basic natural environment (0.734), whereas human-related activities had the weakest direct impact (−0.098). This research offers scientific backing for regional carbon sink evaluation, ecological security early warning, and sustainable development policies.