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Forest fires represent a significant intersection between nature and society, often leading to the loss of natural resources, soil nutrients, and economic opportunities, as well as causing desertification and the displacement of communities. Therefore, the objective of this work is to analyze the multitemporal conditions of a sixth-generation forest fire through the use and implementation of tools such as remote sensing, photointerpretation with geographic information systems (GISs), thematic information on land use, and the use of spatial indices such as the Normalized Difference Vegetation Index (NDVI), the Normalized Burned Ratio (NBR), and its difference (dNBR) with satellite images from Sentinel-2. To improve our understanding of the dynamics and changes that occurred due to the devastating forest fire in Los Guájares, Granada, Spain, in September 2022, which affected 5194 hectares and had a perimeter of 150 km, we found that the main land use in the study area was forest, followed by agricultural areas which decreased from 1956 to 2003. We also observed the severity of burning, shown with the dNBR, reflecting moderate–low and moderate–high levels of severity. Health and part of the post-fire recovery process, as indicated by the NDVI, were also observed. This study provides valuable information on the spatial and temporal dimensions of forest fires, which will favor informed decision making and the development of effective prevention strategies. Full article

Changes in cultivated land use significantly impact food production capacity, which in turn affects food security. Therefore, accurately understanding the spatial and temporal variations in cultivated land use is critical for strategic decision-making regarding national food security. Since the second national soil survey was conducted in around 1980, China has implemented major efforts, such as a nationwide soil testing and fertilization project in around 2005 and the establishment of the National Standards for Cultivated Land Quality Grading in 2016. However, limited research has focused on how cultivated land use has changed during these periods and the mechanisms driving these changes. This study, using Enshi Prefecture in the mountainous region of southwestern Hubei Province as a case study, examines the spatiotemporal changes in cultivated land use during 1980–2018. Land use data from 1980, 2005, and 2018 were combined with statistical yearbook data from Enshi Prefecture, and remote sensing and GIS technology were applied. Indicators such as the dynamic degree of cultivated land use, the relative rate of change in cultivated land use, and a Geoscience Information Atlas model were used to explore these changes. Additionally, principal component analysis was employed to examine the mechanisms influencing these changes. The results show that (1) the area of cultivated land in Enshi Prefecture increased slightly from 1980 to 2005, while from 2005 to 2018, it significantly decreased; compared with the earlier period, the transformation of land use types during 2005–2018 was more intense; (2) the increase in cultivated land area from 1980 to 2005 was mainly due to deforestation, the creation of farmland from lakes, and the reclamation of wasteland, while the decrease in land area was primarily attributed to the conversion of farmland back to forests and grassland. From 2005 to 2018, the main drivers for the increase in cultivated land were deforestation and the reclamation of wasteland, while the return of farmland to forests remained the primary reason for the decrease in land area; (3) from 1980 to 2005, the dynamic degree of cultivated land use in each county and city of Enshi Prefecture was generally low. However, between 2005 and 2018, the dynamic degree increased in most counties and cities except Enshi City and Xianfeng County; (4) there were significant variations in the relative rate of change in cultivated land utilization across counties and cities from 1980 to 2005. However, from 2005 to 2018, the relative rate of change decreased in all counties and cities compared to the previous period; (5) since 1980, nearly 50% of the cultivated land in Enshi Prefecture has undergone land classification conversion, with frequent shifts between different land classes; and (6) economic development, population growth, capital investment, food production, and production efficiency are the dominant socioeconomic factors driving changes in cultivated land use in Enshi Prefecture. The results of this study can provide a scientific basis for the protection and optimization of cultivated land resources in the mountainous regions of southwestern Hubei Province. Full article

Global changes have led to significant changes in soil erosion on the Loess Plateau. Soil erosion leads to the degradation of land resources and a decline in soil fertility, adversely affecting agricultural production and the socioeconomic situation. Therefore, revealing the spatiotemporal evolution patterns of soil erosion in the Loess Plateau region and investigating the influencing factors that contribute to soil erosion are crucial for its management and restoration. In this study, the RUSLE monthly model and the Geodetector model were utilized to reveal the spatiotemporal trends of soil erosion in the Loess Plateau from 2000 to 2020 and to determine the dominant influencing factors in different periods. The main results are as follows: (1) From 2000 to 2020, the soil erosion in the Loess Plateau initially weakened and then intensified, indicating that precipitation and precipitation intensity have different effects on surface soil. (2) From 2000 to 2015, the area experiencing slight and mild erosion increased. This is attributed to the increase in vegetation coverage in the Loess Plateau region, which has alleviated soil erosion in the area. (3) From 2000 to 2020, zones of severe soil erosion were mainly located in the cities of Yan’an and Yulin and their surrounding areas. The gravity center of soil erosion shifted northwestward from Yan’an City overall, indicating an improvement in the soil erosion conditions in the Yan’an area. (4) The predominant level of soil erosion across different land-use types was slight erosion, accounting for over 40%. This may be a result of forestry ecological projects that effectively reduce soil loss. (5) In slope zones of 0–5°, slight erosion accounted for the largest area proportion. As the slope increased, the area proportion of severe and extremely severe erosion also increased. This is attributed to the protective role of vegetation on soil in gentle slope areas. (6) From 2000 to 2020, vegetation was the dominant single factor influencing the spatiotemporal changes in soil erosion, while the interactions between vegetation and land use had the largest explanatory power, indicating that changes in land-use types partially affect variations in vegetation coverage. Our research findings could provide important data support for soil erosion control and eco-environment restoration in the Loess Plateau region. Full article

Urbanization is inevitably accompanied by drastic changes in regional land use and therefore presents an evident influence on ecosystems. Habitat quality (HQ) reflects the ability of a habitat to provide suitable conditions for the survival of an individual or population, and clarifying the interrelationships between urbanization level (UL) and HQ provides insights into sustainable urbanzation and ecosystems conservation. Much attention has focused on how urbanization related to HQ at multi-scales, but few studies have analyzed the interactive coercive relationships between UL and HQ on the global county level. To address this gap, we adopted the bivariate spatial autocorrelation and coupling coordination degree (CCD) model to determine their interactive coercive relationships at the county level globally. Results showed that the global average UL was 0.0807, 0.0838, and 0.0857 in 2000, 2010, and 2020, respectively, with a continuously increasing trend. The global average HQ was 0.6186, 0.6133, and 0.6111 for 2000, 2010, and 2020, reflecting opposite declining trends. The Moran’s I of population urbanization and HQ in 2000, 2010, and 2020 globally remained negative but showed an increasing trend, with values of −0.189, −0.228, and −0.254, respectively, while those of economic urbanization and HQ and land urbanization and HQ also remained negative and exhibited a similar increasing trend. The spatial autocorrelations for UL and HQ in different dimensions indicated that deserts and plateaus functioned as catchment areas with low UL and HQ. The CCD between UL and HQ in each county globally ranged from 0 to 0.70, while CCD between land urbanization and HQ was the most optimal at 0–0.90. The CCD between population urbanization and HQ was similar to that of economic urbanization in terms of spatial distribution. Nevertheless, the CCD of land urbanization in HQ exhibited the greatest degree of coordination among the three urbanization dimensions during the study period. These findings provided important support for sustainable urbanization and ecosystem protection globally. Full article

Fly ash (FA) is the main solid waste emitted from coal-fired power plants. Due to its high yield, low utilization rate, and occupation of a large amount of land, it exerts enormous pressure on the Earth’s environment. With the deepening of the concept of sustainable development, exploring the reuse of industrial waste such as FA has become a key strategy. If FA can be combined with commonly used jewelry in people’s lives, it will be of great significance to promote the high-net-worth utilization of FA. Therefore, this study synthesized a fly-ash-based composite material with color-changing function and combined it with necklaces as the main material. In the first stage, after blending fly ash and slag, an alkaline activator with a total mass of 10% was added. When the proportion of fly ash was 60%, the compressive strength of the prepared fly-ash-based composite material reached 10.1 MPa. This was attributed to the reaction between sodium silicate in the alkaline activator and free CaO, MgO, and other substances in the fly ash to form hydrated silicate colloids, which solidify the fly ash and transform it into a complex three-dimensional network skeleton. In the second stage, a UV resistant coating with thermochromic function was obtained by blending acrylic resin, TiO₂, and a thermosensitive color-changing agent. It was applied to the surface of fly-ash-based composite materials, and the results showed that as the content of the color-changing agent increased, the number of pores on the surface of the coating gradually decreased. When the content of color-changing agent was 10%, the prepared 10%FAB not only had good surface color but also had good thermal stability, UV absorption ability, superhydrophobicity, and mechanical properties. Therefore, 10%FAB was selected as the basic material for jewelry design. In the third stage, the traditional Chinese technique of “gold inlaid with jade” was utilized to develop jewelry applications for the FA composites. As such, 10%FAB was processed into necklaces, which not only had modern design aesthetics but also had good color-changing effects above 30 °C. And after a long period of UV aging experiments, the necklace did not show any wrinkles, bubbles, or other phenomena. Due to the excitation of TiO₂ hole–electron pairs, the necklace’s UV absorption ability was further improved. This study demonstrates the potential application of industrial waste in decorative products, expands the high-end utilization of fly ash as a low-cost material, and provides new ideas for building a low-carbon lifestyle. Full article

Highways and their surrounding areas in mountainous and plateau regions are particularly susceptible to environmental changes, which can significantly impact their safety. In the context of global warming, the magnitude of environmental changes around highways has been further amplified. These environmental disturbances pose substantial risks to highway infrastructure in mountainous regions. By using satellite data and remote sensing techniques, this study focused on the environmental variations of the Du-Ku Highway (DKH) in the Tianshan Mountains and the preliminary revealed shifts in surface water, land surface temperature (LST), normalized difference vegetation index (NDVI), and temperature vegetation dryness index (TVDI) since 2000. The quantitative results showed that the water bodies with area between 0.1 and 0.5 ha showing the most significant growth around the DKH. The LST values are primarily distributed between 280 and 285 K, while the NDVI values are mostly below 0.4, and the TVDI is mainly concentrated at the two extremes. In the context of global warming and its amplified impact on mountainous and plateau regions, these findings offer critical insights that can directly support mountainous highway construction and maintenance strategies by identifying environmental indicators, providing a scientific foundation for making data-driven decisions. Full article

In China’s rural areas, as populations flow into cities, dependence on land has significantly decreased, leading to widespread land abandonment; however, the relationship between population and land in pastoral areas differs. This study conducted a five-year tracking survey on Sunite Right Banner in Xilingol League (Inner Mongolia), where macro data and in-depth home interviews were used for the mechanisms’ analysis. The findings demonstrate that the pastoral regions’ ecological pressure has increased with population immigration. There are several factors influencing such interaction between people and rangeland: First is the cost mechanism. The increasing cost of livestock production leads herders to increase their reliance on grazing rental systems to increase the number of livestock. The grazing rental system generates income for those migrating to adjacent urban regions. Second is the institutional mechanism. The “three-separating property right systems”, a recent rural land institutional reform policy, has marketized rural individualized rangelands, leading herders to focus more on the exchange value of rangelands rather than the use value, including ecological functions. Consequently, both lessors and lessees engage in high-intensity utilization of their individualized grazing lands. Third is the natural mechanism. Climate fluctuations influence herders’ migration patterns, prompting them to leave and return to grazing lands. These ecological dynamics force herders to oscillate between survival and development, intensifying pressure on the grasslands during favorable years and preventing them from recovering while increasing the occurrence of poor years, such as droughts. Fourth is the consumption mechanism. Herders who have migrated to urban regions must continue relying on rangeland resources to sustain their livelihoods. However, lower economic outputs of livestock production hardly catch up with the higher consumption levels in urban regions, which leads migrated herders to increase their pressure on rural rangelands. The final factor is a combination of the previous four mechanisms. The interplay between these previously mentioned four mechanisms encouraged higher herder population outflow, though their reliance on rangeland resources has continued. Based on the results, we argue that these dynamic relations between rural population change and land use patterns are becoming common issues across pastoral regions in Inner Mongolia, demanding innovative solutions. Full article

Growing human demands are placing significant pressure on groundwater resources, causing declines in many regions. Identifying areas where groundwater levels are declining due to human activities is essential for effective resource management. This study investigates the influence of land use and land cover, crop types, and precipitation patterns on groundwater level trends across the Mississippi River Watershed (MRW), USA. Groundwater storage changes from 2003 to 2015 were estimated using data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. A spatiotemporal analysis was conducted at four scales: the entire MRW, groundwater regimes based on groundwater level change rates, 31 states within the MRW, and six USGS hydrologic unit code (HUC)-2 watersheds. The results indicate that the Lower Mississippi region experienced the fastest groundwater decline, with a Sen’s slope of −0.07 cm/year for the mean equivalent water thickness, which was attributed to intensive groundwater-based soybean farming. By comparing groundwater levels with changes in land use, crop types, and precipitation, trends driven by human activities were identified. This work underscores the ongoing relevance of GRACE data and the GRACE Follow-On mission, launched in 2018, which continues to provide vital data for monitoring groundwater storage. These insights are critical for managing groundwater resources and mitigating human impacts on the environment. Full article

Urban vitality is a concept that reflects dynamic changes in economic, social, and cultural aspects, emphasizing the importance of diversified land use and dense population. With technological advancements, research methods on urban vitality are increasingly diverse, particularly with the application of big data and geographic information systems providing new perspectives and tools for such studies. Currently, research on the vitality of inland Central Plains cities in China is relatively limited and largely confined to specific administrative areas, leading to an inadequate understanding of basic economic activities and population distribution within cities. Therefore, this study aims to explore the spatial distribution characteristics of urban vitality and its influencing factors in Zhengzhou’s main urban area, providing a scientific basis for urban planning and sustainable development. This study utilizes methods that include Densi graph curve analysis, the entropy method, and the multiscale geographically weighted regression (MGWR) model, integrating statistical data, geographic information, and remote sensing imagery of Zhengzhou in 2023. The MGWR model analysis reveals: (1) Urban vitality in Zhengzhou’s main urban area exhibits a concentric pattern, with high vitality at the center gradually decreasing toward the periphery, showing significant spatial differences in economic, population, and cultural vitality. (2) Various influencing factors positively correlate with urban vitality in the main urban area, but due to shortcomings in urban development strategies and planning, some factors negatively impact vitality in the central area while positively affecting vitality in peripheral areas. Based on these findings, this study provides relevant evidence and theoretical support for urban planning and sustainable development in Zhengzhou, aiding in the formulation of more effective urban development strategies. Full article

As talk grows about billions or even trillions of dollars being directed toward potential “Net Zero” activities, it is imperative that the chemistry inherent in or driving those actions make scientific sense. The challenge is to close the mass and energy balances to the carbon and oxygen cycles in the Earth’s atmosphere and oceans. Several areas of climate science have been identified that chemists can investigate through methods that do not require a supercomputer or a climate model for investigation, most notably the following: (1) The carbon cycle, which still needs to be balanced, as many known streams, such as carbon to landfills, carbon in human-enhanced sewage and land runoff streams, and carbon stored in homes and other material, do not seem to have been accounted for in carbon balances used by the IPCC. (2) Ocean chemistry and balances are required to explain the causes of regional and local-scale salinity, pH, and anoxic conditions vs. global changes. For example, local anoxic conditions are known to be impacted by changes in nutrient discharges to oceans, while large-scale human diversions of fresh water streams for irrigation, power, and industrial cooling must have regional impacts on oceanic salinity and pH. (3) Carbon Capture and Storage (CCS) schemes, if adopted on the large scales being proposed (100s to 1000s of Gt net injection by 2100), should impact the composition of the atmosphere by reducing free oxygen, adding more water from combustion, and displacing saline water from subsurface aquifers. Data indicate that atmospheric oxygen is currently dropping at about twice the rate of CO₂ concentrations increasing, which is consistent with combustion chemistry with 1.5 to 2 molecules of oxygen being converted through combustion to 1 molecule of CO₂ and 1 to 2 molecules of H₂O, with reverse reactions occurring as a result of oxygenic photosynthesis by increased plant growth. The CCS schemes will sabotage these reverse reactions of oxygenic photosynthesis by permanently sequestering the oxygen atoms in each CO₂ molecule. Full article

Agricultural soil has great potential to address climate change issues, particularly the rise in atmospheric CO₂ levels. It offers effective remedies, such as increasing soil carbon content while lowering atmospheric carbon levels. The growing interest in inoculating soil with live microorganisms aims to enhance agricultural land carbon storage and sequestration capacity, modify degraded soil ecosystems, and sustain yields with fewer synthetic inputs. Agriculture has the potential to use soil microalgae as inoculants. However, the significance of these microorganisms in soil carbon sequestration and soil carbon stabilization under field conditions has yet to be fully understood. Large-scale commercial agriculture has focused on the development and use of inoculation products that promote plant growth, with a particular emphasis on enhancing yield attributes. Gaining more profound insights into soil microalgae’s role in soil carbon cycling is necessary to develop products that effectively support soil carbon sequestration and retention. This review comprehensively explores the direct and indirect mechanisms through which soil microalgae contribute to soil carbon sequestration, highlighting their potential as microbial inoculants in agricultural settings. This study underlines the need for more research to be conducted on microalgae inoculation into agricultural soil systems aimed at mitigating carbon emissions in the near future. Full article

In recent decades, the integrity and security of the ecosystem in the Sanjiang Plain have faced severe challenges due to land reclamation. Understanding the impact of paddy field expansion on regional ecosystem services (ESs), as well as revealing the trade-offs and synergies (TOS) between these services to achieve optimal resource allocation, has become an urgent issue to address. This study employs the InVEST model to map the spatial and temporal dynamics of five key ESs, while the Optimal Parameter Geodetector (OPGD) identifies primary drivers of these changes. Correlation analysis and Geographically Weighted Regression (GWR) reveal intricate TOS among ESs at multiple scales. Additionally, the Partial Least Squares-Structural Equation Model (PLS-SEM) elucidates the direct impacts of paddy field expansion on ESs. The main findings include the following: (1) The paddy field area in the Sanjiang Plain increased from 5775 km² to 18,773.41 km² from 1990 to 2020, an increase of 12,998.41 km² in 40 years. And the area of other land use types has generally decreased. (2) Overall, ESs showed a recovery trend, with carbon storage (CS) and habitat quality (HQ) initially decreasing but later improving, and consistent increases were observed in soil conservation, water yield (WY), and food production (FP). Paddy fields, drylands, forests, and wetlands were the main ES providers, with soil type, topography, and NDVI emerging as the main influencing factors. (3) Distinct correlations among ESs, where CS shows synergies with HQ and SC, while trade-offs are noted between CS and both WY and FP. These TOS demonstrate significant spatial heterogeneity and scale effects across subregions. (4) Paddy field expansion enhances regional SC, WY, and FP, but negatively affects CS and HQ. These insights offer a scientific basis for harmonizing agricultural development with ecological conservation, enriching our understanding of ES interrelationships, and guiding sustainable ecosystem management and policymaking. Full article

Water ecosystem services (WESs) are intrinsically associated with the livelihood of urban residents and are frequently disrupted by human activities. Land use and landscape patterns are key driving factors of alterations in WESs. However, existing research primarily quantifies single-factor influences and often overlooks the interactions between these factors. This study addresses this gap by employing a multi-model coupling approach, integrating the Patch-generating Land Use Simulation (PLUS), Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, and Geographical Detector (GD) models alongside various indicators to analyse the evolution of land use, landscape patterns and WESs in the Greater Bay Area from 2000 to 2020, and to simulate spatio-temporal change patterns in different scenarios from 2030 to 2050. Additionally, this study examines the multi-factorial interactions between land use, landscape patterns, and WESs. The results indicate that (1) urbanisation steadily increased, leading to intensified landscape fragmentation, and water yield (WY) and total phosphorus (TP) consistently increased, while total nitrogen (TN) in water gradually decreased; (2) urban areas exerted the most significant impact on WY in the Greater Bay Area while Patch density (PD) had a stronger influence on WY, and Shannon’s diversity index (SHDI) had the most pronounced effect on TN and TP; (3) the interaction between any two land-use types or landscape indices exerted a greater impact on WESs compared with the impact of individual factors alone. The interaction between urban areas and cropland substantially influenced WY (q¯ = 0.634) and most strongly affected TN and TP in water (q¯ = 0.74 and 0.73, respectively). SHDI and PD had the most significant impact on WY in the economic development scenario (q¯ = 0.19) and exhibited the greatest influence on the TN and TP levels in the ecological priority scenario (q¯ = 0.12 and 0.15, respectively). Our findings can provide theoretical and technical support for the integrated scientific planning of regional water ecosystems and the development of comprehensive land use policies in the future. Full article

Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) products are essential data sources for global and regional climate change research. Currently, several versions of the MODIS LST product have been released, yet the performance differences and uncertainties they introduce in land surface studies remain insufficiently addressed. To bridge this gap, this study focuses on four distinct versions of the LST product: MxD11A1 Collection 5 (C5), Collection 6 (C6), Collection 6.1 (C6.1), and MxD21A1 Collection 6.1 (MxD21). The spatial resolution of all product generations is 1 km, and the temporal resolution is 0.5 days. This study provides a comprehensive analysis of the errors arising from different generations of these products in various land surface process studies. The error assessment includes cross-comparisons between product versions and evaluations of the absolute errors generated. Absolute errors in evaluation data were collected from 13 surface sites within the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) project during the period 2013–2018. Cross-validation results show that the largest difference between C5 and C6.1 occurs over bare land, with an RMSE of approximately 1.45 K, while there is no significant change between C6 and C6.1. MOD21 shows considerable variation compared to C6.1 at night across different land cover types, with RMSE over cropland exceeding 2 K. The temperature difference between MOD21 and C6.1 is more pronounced at night (2.01 K) than during the day (0.30 K). Validation results based on temperature indicate that C5 has greater uncertainty compared to C6, especially over bare land, where errors are 2.06 K and 1.06 K, respectively. Furthermore, MxD21 demonstrates significant day–night performance discrepancies, with an average bias of 0.10 K at night, while daytime errors over bare land can reach 2 K, potentially influenced by atmospheric conditions. Based on the research in this paper, it is possible to clarify the performance of different versions of MODIS products, reflecting the appropriateness of their past applications; on the other hand, it is recommended to prioritize the use of the MxD11A1 C6 and C6.1 products for monitoring and applications in bare soil areas to ensure higher accuracy. Furthermore, for day and night monitoring, it may be beneficial to alternate between the MxD11A1 and MxD21A1 products to fully leverage their respective advantages and enhance overall monitoring effectiveness. Full article