Fertilization can significantly affect the quality of crop and soil. To determine the effects of long-term fertilization on crop yield and carbon:nitrogen:phosphorus (C:N:P) stoichiometry in soil, a study was conducted on the terraced fields of the Loess Plateau from 2007 to 2019. Nine fertilization treatments were included: no fertilizer; organic fertilizer (O); organic and nitrogen fertilizers (ON); organic, nitrogen, and phosphorus fertilizers (ONP); organic and phosphorus fertilizers (OP); phosphorus and nitrogen fertilizers; potash and nitrogen fertilizers; potash, nitrogen, and phosphorus fertilizers; and potash and phosphorus fertilizers. Under these treatments except for CK and PK, crop yields initially decreased but later increased. The nutrient content and C:N:P stoichiometry increased in soil depth of 0–20 cm. The soil available nutrients did not change significantly with the duration of fertilization. The O, ON, ONP, and OP had the most evident effect on the enhancement of soil nutrient content, whereas O and ON had the most evident effect on the increase in soil organic carbon (SOC):total phosphorus (TP) and total nitrogen (TN):TP. In soil depth of 0–20 cm, crop yield, SOC:TN, SOC:TN, SOC:TP, and TN:TP significantly correlated with soil nutrients. This study indicated that long-term fertilization can effectively improve crop yield, soil fertility, and soil C:N:P stoichiometry. Meanwhile, the single application of an organic fertilizer or the combination of organic and nitrogen fertilizers can improve the condition of nitrogen limitation in arid and semi-arid areas.

Landsat remote sensing images obtained from 2000, 2005, 2010, 2015, and 2020 were analyzed. The normalized vegetation index (NDVI), moisture index (WET), land surface temperature (LST), and normalized building-soil index (NDBSI) were extracted based on the four aspects of greenness, humidity, heat, and dryness. The Remote Sensing Ecological Index (RSEI) was calculated using principal component analysis to quantitatively analyze and dynamically monitor and evaluate the ecological environment changes in the Kuye River Basin over the past 20 years. From the perspective of spatial and temporal distribution, the ecological and environmental quality of Kuye River Basin had a downward trend from 2000 to 2020. The overall RSEI grade was medium or poor, and the average RSEI decreased. The proportion of excellent and good grade watershed areas decreased, whereas that of medium, low, and poor grade watershed areas increased over the study period. Spatially, RSEI decreased gradually from southeast to northwest. The degraded areas were mainly distributed in urban areas with frequent human activities. Conversely, the superior eco-environmental quality areas were mainly distributed in eastern sections of the watershed. Compared with 2000, the eco-environmental quality of the Yulin urban area and Shenmu County in the southern section of the watershed are worsening.

Soil water and nutrients are major factors limiting crop productivity. In the present study, soil water use efficiency (WUE) and crop yield of millet and soybean were investigated under nine fertilization regimes (no nitrogen (N) and no phosphorus (P) (CK), 120 kg ha⁻¹ N and no P (N1P0), 240 kg ha⁻¹ N and no P (N2P0), 45 kg ha⁻¹ P and no N (N0P1), 90 kg ha⁻¹ P and no N (N0P2), 120 kg ha⁻¹ N and 45 kg ha⁻¹ P (N1P1), 240 kg ha⁻¹ N and 45 kg ha⁻¹ P (N2P1), 120 kg ha⁻¹ N and 90 kg ha⁻¹ P (N1P2), 240 kg ha⁻¹ N and 90 kg ha⁻¹ P (N2P2)) in the Loess Plateau, China. We conducted fertilization experiments in two cultivation seasons and collected soil nutrient, water use, and crop yield data. Combined N and P fertilization resulted in the greatest increase in crop yield and WUE, followed by the single P fertilizer application, and single N fertilizer application. The control treatment, which consisted of neither P nor N fertilizer application, had the least effect on crop yield. The combined N and P fertilization increased soil organic matter (SOM) and soil total N, while soil water consumption increased in all treatments. SOM and total N content increased significantly when compared to the control conditions, by 27.1–81.3%, and 301.3–669.2%, respectively, only under combined N and P application. The combined N and P application promoted the formation of a favorable soil aggregate structure and improved soil microbial activity, which accelerated fertilizer use, and enhanced the capacity of soil to maintain fertilizer supply. Crop yield increased significantly in all treatments when compared to the control conditions, with soybean and millet yields increasing by 82.5–560.1% and 55–490.8%, respectively. The combined application of N and P fertilizers increased soil water consumption, improved soil WUE, and satisfied crop growth and development requirements. In addition, soil WUE was significantly positively correlated with crop yield. Our results provide a scientific basis for rational crop fertilization in semi-arid areas on the Loess Plateau.

To investigate the status of heavy metal pollution and the associated ecological and health risks in farmland surrounding the Xicheng lead and zinc mining area, we collected soil samples (0–20 cm) and measured the level of As, Ni, Cu, Zn, Cd, Pb, Hg, and Cr. The characteristics of soil heavy metals, pollution levels, and ecological, and health risks were quantitatively assessed using Monte Carlo simulation in conjunction with the geo-accumulation index (Igeo), pollution index (Pi), ecological risk index (Er), and human health risk assessment model. The results indicated that the average concentrations of As, Ni, Cu, Zn, Cd, Pb, Hg, and Cr in the soil of the study area were 26.92, 39.46, 31.18, 340.23, 1.13, 184.61, 0.34, and 71.15 mg·kg⁻¹, respectively. These values were significantly higher than the soil background levels reported for Gansu Province. The average Igeo for Hg was 3.27, and the average Er was 679.13, indicating that Hg had the highest accumulation and posed the greatest ecological risk in the study area. The average single-factor pollution index for Cd was 2.52, marking it as the heavy metal with the highest pollution level. The cumulative probability of health risk derived from Monte Carlo simulation indicates that the non-carcinogenic hazard indices for adults and children were 2.79 × 10⁻¹ and 1.67, respectively, with 94.82% of children exceeding the non-carcinogenic risk threshold. The carcinogenic risk indices (TCR) for adults and children were 8.09 × 10⁻⁵ and 4.60 × 10⁻⁴, respectively, and 100% of the samples exceeded the TCR standard for children. As and Cd were identified as the primary contributors to both carcinogenic and non-carcinogenic risks. The findings enhance our understanding of heavy metal contamination in farmland soils and establish an empirical framework for developing targeted remediation approaches and sustainable land management practices.

The global push toward digital transformation in education presents both opportunities and challenges for achieving sustainability goals. While digital technologies promise enhanced learning experiences and reduced environmental impacts, their implementation often overlooks complex trade-offs between pedagogical effectiveness, resource efficiency, and social equity. This study examines these critical intersections through a comprehensive investigation of geography education in Chinese secondary schools, comparing traditional, fully digital, and hybrid models across diverse urban, suburban, and rural contexts. Through a mixed-methods comparative design involving 262 participants (pilot) and 810 students (main study) and analysis of 17 geography textbooks, we assessed the environmental impacts, learning outcomes, economic viability, and social equity dimensions of each approach. Our findings reveal that thoughtfully designed hybrid models—which strategically combine digital tools for high-impact activities with traditional methods for local engagement—achieve optimal sustainability performance. These hybrid approaches reduced carbon emissions by 72.7% compared to traditional methods while improving learning outcomes and maintaining cost parity over five-year periods. Importantly, hybrid models demonstrated superior adaptability across different socioeconomic contexts, addressing equity concerns that purely digital approaches often exacerbate in resource-limited settings. This research challenges the prevailing technology-first narratives in educational reform, demonstrating that sustainable education transformation requires nuanced, context-sensitive integration strategies rather than wholesale digital transformation. The empirical evidence from this research provides robust support for achieving the United Nations Sustainable Development Goals through educational innovation. The hybrid model’s 73% carbon reduction and simultaneous improvement of learning outcomes by 35% directly support SDG 4 (Quality Education) and SDG 13 (Climate Action). The 78% reduction in paper consumption advances SDG 12 (Responsible Consumption and Production), while successful implementation across urban, suburban, and rural contexts addresses SDG 10 (Reduced Inequalities). These findings demonstrate that sustainable educational transformation can effectively balance technological innovation with environmental stewardship and social equity.

Land use conflicts represent an increasing challenge to sustainable development, particularly in regions undergoing rapid urbanization. This study investigated the spatiotemporal dynamics of land use conflicts and their ecological implications in Tianshui City from 1980 to 2020. The main objectives were to identify patterns of spatial heterogeneity, explore the driving factors behind these conflicts, and analyze their relationship with the ecological risks. The results indicate the following findings. In terms of spatiotemporal heterogeneity, early land use changes were primarily driven by structural factors, such as topography and climate, with a Nugget/Still ratio of 0.36. Regarding conflict intensity, high-conflict areas expanded by approximately 1110 square kilometers between 1980 and 2020, predominantly concentrated in fertile agricultural regions such as the Weihe River Basin and urban core areas. Conversely, non-conflict zones decreased by 38.7%. In terms of ecological risk correlation, bivariate LISA cluster analysis revealed a significant spatial autocorrelation between severe land use conflicts and ecological risks (Moran’s I = 0.62, p < 0.01). High-risk clusters in areas transitioning from arable land to built-up land increased by 23% after 2000. Predictions based on the future land-use simulation (FLUS) model suggest that by 2030, high-intensity conflict areas will expand by an additional 16%, leading to intensified competition for land resources. Therefore, incorporating ecological safety thresholds into land spatial planning policies is essential for reconciling the conflicts between development and conservation, thereby promoting sustainable land use transitions.