Search Results (184)

As a typical grain base with a dense population and high-level urbanization, the North China Plain (NCP) faces a serious threat to its sustainable development due to water shortage. Surface water area (SWA) is a key indicator for continuously measuring the trends of regional water resources and assessing their current status. Therefore, a deep understanding of its changing patterns and driving forces is essential for achieving the sustainable management of water resources. In this study, we examined the interannual variability and trends of SWA in the NCP from 1990 to 2023 using annual 30 m water body maps generated from all available Landsat imagery, a robust water mapping algorithm, and the cloud computing platform Google Earth Engine (GEE). The results showed that the SWA in the NCP has significantly increased over the past three decades. The continuous emergence of artificial reservoirs and urban lakes, along with the booming aquaculture industry, are the main factors driving the growth of SWA. Consequently, the expansion of artificial water bodies resulted in a significant increase in water evaporation (0.16 km³/yr). Moreover, the proportion of water evaporation to regional evapotranspiration (ET) gradually increased (0–0.7%/yr), indicating that the contribution of water evaporation from artificial water bodies to ET is becoming increasingly prominent. Therefore, it can be concluded that the ever-expanding artificial water bodies have become a new hidden danger affecting the water security of the NCP through evaporative loss and deserve close attention. This study not only provides us with a new perspective for deeply understanding the current status of water resources security in the NCP but also provides a typical case with great reference value for the analysis of water resources changes in other similar regions. Full article

Food security is crucial for social stability and economic development. Ensuring food security in the arid region of Northwest China presents unique challenges due to limited water and soil resources. This study addresses these challenges by integrating a comprehensive water and soil resource matching assessment with grain production forecasting. Based on data from 2000 to 2020, this research projects the food security status to 2035 using the GM(1,1) model, incorporating a comprehensive index of soil and water resource matching and regression analysis to inform production forecasts. Key assumptions include continued historical trends in population growth, urbanization, and dietary shifts towards an increased animal protein consumption. The findings revealed a consistent upward trend in grain production from 2000 to 2020, with an average annual growth rate of 3.5%. Corn and wheat emerged as the dominant grain crops. Certain provinces demonstrated comparative advantages for specific crops like rice and wheat. The most significant finding is that despite the projected growth in the total grain output by 2035 compared to 2020, the regional grain self-sufficiency rate is projected to range from 79.6% to 84.1%, falling below critical food security benchmarks set by the FAO and China. This projected shortfall carries significant implications, underscoring a serious challenge to regional food security and highlighting the region’s increasing vulnerability to external food supply fluctuations. The findings strongly signal that current trends are insufficient and necessitate urgent and proactive policy interventions. To address this, practical policy recommendations include promoting water-saving technologies, enhancing regional cooperation, and strategically utilizing the international grain trade to ensure regional food security. Full article

With rapid socio-economic development, excessive anthropogenic consumption and the exploitation of natural resources have impaired the self-healing, supply, and carrying capacities of ecosystems. The assessment and prediction of ecosystem service values (ESVs) are crucial for the coordinated development of ecology and economy. This research examines the Xiangjiang River Basin and combines land use data from 1995 to 2020, Landsat images, meteorological data, and socio-economic data. These data are incorporated into the PLUS model to simulate land use patterns in 2035 under the following five scenarios: natural development, economic development, farmland protection, ecological protection, and coordinated development. Additionally, this research analyzes the dynamics of land use and changes in ESVs in the Xiangjiang River Basin. The results show that between 1995 and 2020 in the Xiangjiang River Basin, urbanization accelerated, human activities intensified, and the construction land area expanded significantly, while the areas of forest, farmland, and grassland decreased continuously. Based on multi-scenario simulations, the ESV showed the largest and smallest declines under economic development and ecological protection scenarios, respectively. This results from the economic development scenario inducing a rapid expansion in construction land. In contrast, construction land expansion was restricted under the ecological protection scenario, because the ecological functions of forests and water bodies were prioritized. This research proposes land use strategies to coordinate ecological protection and economic development to provide a basis for sustainable development in the Xiangjiang River Basin and constructing a national ecological security barrier, as well as offer Chinese experience and local cases for global ecological environment governance. Full article

The South-to-North Water Diversion Project constitutes a fundamental initiative designed to enhance water resource distribution and foster regional coordinated development. To investigate the coupling coordination and its spatiotemporal evolution between high-quality development and ecological security (HQD-ES) within the project’s water source areas, this research established a dedicated evaluation index system. Employing coupling coordination, spatial autocorrelation, and Geographically Weighted Regression (GWR) models, the study analyzed the coupled coordination state and its spatiotemporal characteristics across these water source areas for the period 2010–2023. The findings demonstrated that (1) the high-quality development trend remained generally positive, rising from 0.253 to 0.377; ecological safety level showed sustained improvement, increasing from 0.365 to 0.731. (2) The coupling degree (CD) was in a high coupling stage on the whole; the coupling coordination degree (CCD) increased significantly, from imminent imbalance to good coordination state, and the space pattern showed “prominent in the middle and stable in the north and south”. (3) There was no obvious spatial correlation existing between the CCD of HQD-ES in Nanyang City. Tongba, Fangcheng, and Xinye displayed spatial correlation characteristics of low-high aggregation and high-low aggregation. GWR results showed that industrial structure, urbanization, and greening level promoted CCD, while economic level, population density, and environmental regulation inhibited it. Full article

Land use and land cover (LULC) in Northern Bangladesh have undergone substantial transformations due to both anthropogenic and natural drivers. This study examines historical LULC changes (1990–2022) and projects future trends for 2030 and 2054 using remote sensing and the Cellular Automata-Artificial Neural Network (CA-ANN) model. Multi-temporal Landsat imagery was classified with 80.75–86.23% accuracy (Kappa: 0.75–0.81). Model validation comparing simulated and actual 2014 data yielded 79.98% accuracy, indicating a reasonably good performance given the region’s rapidly evolving and heterogeneous landscape. The results reveal a significant decline in waterbodies, which is projected to shrink by 34.4% by 2054, alongside a 1.21% reduction in cropland raising serious environmental and food security concerns. Vegetation, after an initial massive decrease (1990–2014), increased (2014–2022) due to different forms of agroforestry practices and is expected to increase by 4.64% by 2054. While the model demonstrated fair predictive power, its moderate accuracy highlights challenges in forecasting LULC in areas characterized by informal urbanization, seasonal land shifts, and riverbank erosion. These dynamics limit prediction reliability and reflect the region’s ecological vulnerability. The findings call for urgent policy action particularly afforestation, water resource management, and integrated land use planning to ensure environmental sustainability and resilience in this climate-sensitive area. Full article

Urbanization is rapidly transforming cities, especially in the Global South, with Sub-Saharan Africa expected to see the fastest growth in the next 30 years. In South Africa’s Mopani District, this urban expansion has led to the growth of informal settlements, increasing disaster risks related to water, health, and fire. This study focuses on Giyani Local Municipality, examining disaster risks in its informal settlements and the factors influencing the implementation of spatial planning tools. Using a SWOT analysis combined with the Analytical Hierarchy Process (AHP), the study found that while the municipality has strong land use and disaster management policies, poor enforcement, lack of integration, and weak governance limit their effectiveness. Opportunities for improvement include securing grants from the National Government and Disaster Management Centre to support disaster risk reduction (DRR) initiatives. However, challenges such as land shortages and ecological degradation threaten sustainable planning. The findings provide important insights for policymakers, urban planners, and disaster management professionals. The SWOT-AHP approach helps in prioritizing resource allocation, identifying risk trends, and focusing on key areas for mitigation. Overall, the study supports efforts to enhance resilience and promote sustainable urban development in informal settlements through better spatial planning. Full article

The transformative trajectory of urban development in the contemporary era has engendered a substantial escalation in construction waste generation, particularly in China, where it constitutes approximately 40% of the total solid waste stream. Traditional landfill disposal methodologies pose formidable ecological challenges, encompassing soil contamination, groundwater pollution, and significant greenhouse gas emissions. Furthermore, the unsustainable exploitation of natural sandstone resources undermines energy security and disrupts ecological balance. In response to these pressing issues, an array of scholars and researchers have embarked on an exploratory endeavor to devise innovative strategies for the valorization of construction waste. Among these strategies, the conversion of waste into recycled aggregates has emerged as a particularly promising pathway. However, the practical deployment of recycled aggregates within the construction industry is impeded by their inherent physico-mechanical properties, such as heightened water absorption capacity and diminished compressive strength. To surmount these obstacles, a multitude of enhancement techniques, spanning physical, chemical, and thermal treatments, have been devised and refined. This paper undertakes a comprehensive examination of the historical evolution, recycling methodologies, and enhancement strategies pertinent to recycled aggregates. It critically evaluates the efficacy, cost–benefit analyses, and environmental ramifications of these techniques, while elucidating the microstructural and physicochemical disparities between recycled and natural aggregates. Furthermore, it identifies pivotal research gaps and prospective avenues for future inquiry, underscoring the imperative for collaborative endeavors aimed at developing cost-effective and environmentally benign enhancement techniques that adhere to the stringent standards of contemporary construction practices, thereby addressing the intertwined challenges of waste management and resource scarcity. Full article

As urbanization progresses at an accelerating pace, the depletion of natural resources and environmental degradation are becoming increasingly severe. Constructing ecological security patterns (ESPs) has become a crucial strategy for mitigating environmental stress and promoting sustainable social development. Currently, the methods for constructing ESPs remain under exploration. Particularly, in the identification of ecological sources, insufficient emphasis has been placed on trade-offs among ecosystem services (ESs). This study focuses on Liaoning Province, situated in China’s northeast revitalization area—a region with a developed heavy industry and abundant ecological resources. The InVEST model was employed to assess ESs, and the ordered weighted average (OWA) method was utilized to identify ecological sources. By integrating both natural and social factors, the ecological resistance surface was constructed, and circuit theory was applied to determine ecological corridors, ultimately leading to the development of an ESP. The results show that (1) between 2010, 2015, and 2020, water yield continued to increase, habitat quality continuously declined, soil conservation tended to decrease and then gradually increase, and carbon storage tended to increase and then decrease. The four ESs show similar spatial features, characterized by elevated levels in the eastern and western areas and a comparatively reduced level in the central region; (2) a total of 179 ecological sources were identified, covering 26,235.34 km². The overall distribution showed a concentration in the east, with a fragmented and dispersed pattern in the southwest. The identification of 435 ecological corridors, with an overall length totaling 8794.59 km, resulted in a network-like distribution pattern. Additionally, 65 ecological pinch points and 67 barrier points were identified; and (3) a “four zones, three corridors, and two belts” pattern of ecological protection and restoration has been proposed. The findings offer valuable insights for Liaoning Province and other rapidly developing regions facing escalating environmental pressures. Full article

This review aims to increase attention on present water quality issues on Central Asia, finding gaps in the literature on ways to address treatment needs, and help ensure future use of Central Asia surface waters and groundwater for all beneficial uses. Central Asia is a landlocked region known for its harsh climatic conditions and scarce water resources, despite being home to some of the world’s largest internal drainage basins. The available literature suggests that increasing salinity has rendered water unsuitable for irrigation and consumption; hazardous trace elements are found throughout Central Asia, most often associated with mining and industrial sources; and that legacy pesticides influence water quality, particularly in agriculturally influenced basins. This study also focuses on the effects of municipal and industrial wastewater discharge. Additionally, the impact of inadequately treated wastewater on water resources is analyzed through a review of available data and reports regarding surface and groundwater quantity and quality. Given the challenges of water scarcity and accessibility, the reuse of treated wastewater is becoming increasingly important, offering a valuable alternative that necessitates careful oversight to ensure public health, environmental sustainability, and water security. However, due to insufficient financial and technical resources, along with underdeveloped regulatory frameworks, many urban areas lack adequate wastewater treatment facilities, significantly constraining their safe and sustainable reuse. Proper management of wastewater effluent is critical, as it directly influences the quality of both surface and groundwater, which serve as key sources for drinking water and irrigation. Due to their persistent and biologically active nature even at trace levels, we discuss contaminants of emerging concern such as antibiotics, pharmaceuticals, and modern agrochemicals. This review thus highlights gaps in the literature reporting on impacts of wastewater inputs to water quality in Central Asia. It is recommended that future research and efforts should focus on exploring sustainable solutions for water quality management and pollution control to assure environmental sustainability and public health. Full article

Brazil is increasingly affected by extreme weather events due to climate change, with pronounced regional differences in temperature and precipitation patterns. The southeast region is particularly vulnerable, frequently experiencing severe droughts and extreme heatwaves linked to atmospheric blocking events and intense rainfall episodes driven by the South Atlantic Convergence Zone (SACZ). These phenomena contribute to recurring climate-related disasters. The country’s heavy reliance on hydropower heightens its susceptibility to droughts, while growing evidence points to intensifying dry spells and wildfires across multiple regions, threatening agricultural output and food security. Urban areas, particularly, are experiencing more frequent and severe heatwaves, posing serious health risks to vulnerable populations. This study investigates the links between global teleconnection indices and synoptic-scale systems, specifically blocking events and SACZ activity, and their influence on Brazil’s extreme heat, drought conditions, and river flow variability over the past 30 to 40 years. By clarifying these interactions, the research aims to enhance understanding of how large-scale atmospheric dynamics shape climate extremes and to assess their broader implications for water resource management, energy production, and regional climate variability. Full article

Drought frequency and severity intensify with climate change, challenging many Mediterranean cities to face securing sustainable water supplies. In this context, groundwater emerges as a key but often overlooked resource, particularly in urban areas historically reliant on external drinking water systems. This study provides a comprehensive hydrogeological characterisation of the groundwater system in Aix-en-Provence (southeastern France), with a specific focus on hypothermal springs and the cold springs of the Vallon des Pinchinats, which historically supplied the town before the creation of the Canal de Provence by the company of the same name (Société du Canal de Provence (SCP)). By combining chemical and isotopic analyses (δ¹⁸O, δ²H, and chloride concentrations) with a statistical clustering (DACMAD method), we characterise the origin and dynamics of distinct water sources and evaluate their influence with surface water and external supply systems. Four key hydrological entities influencing the study area were identified. (1) regional precipitation (RRW) contributing significantly to groundwater recharge in the region. The isotope composition of the RRW was calculated (δ¹⁸O: −6.68‰, δ²H: −41.80‰, Cl: 2.2 mg/L) (2) Groundwater from the Oligocene aquifer (OG) characterised by an enrichment in chloride and sulphate. (3) Groundwater from the Cretaceous–Jurassic aquifer (CJG), a karstified aquifer from the Sainte-Victoire-Concors massif, which supplies the cold and hypothermal springs in Aix-en-Provence and multiple springs in the region. (4) Canal de Provence water (CPW) as an external water source, used for domestic supply, which has left a traceable signal in the local hydrosystem. The study reveals that cold springs of the Vallon des Pinchinats result from the mixing of Oligocene and Cretaceous–Jurassic groundwaters. Hypothermal springs (20–30 °C) circulate at moderate depths (165–500 m), unlike previous models suggesting deeper infiltration and mixing processes. This study contributes a novel hydrogeochemical and isotopic framework applicable to other Mediterranean urban areas facing similar pressures and highlights the strategic role that local groundwater can play in building long-term water resilience. Full article

Rapid socio-economic development has intensified the conflict between supply and demand for regional water resources, necessitating optimized water resource allocation to enhance water security. This study establishes a multi-objective water resource optimization model by comprehensively considering economic, social, and ecological benefits. Based on the Non-dominated Sorting Genetic Algorithm-III (NSGA-III), we propose the I-NSGA-III algorithm by integrating reference point improvement strategies, dynamic retention of high-quality solutions, and optimized selection strategies to solve the multi-objective optimization model. A multi-system coupling coordination evaluation model is constructed to assess the final allocation schemes. Compared with some commonly used multi-objective algorithms and tested using the DTLZ series functions, the proposed algorithm demonstrates improved overall performance. Specifically, the IGD indicator decreases by 5.17–50.22%, and the HV indicator increases by 2.71–25.51% compared to NSGA-III. The proposed model is applied to Jinzhong City, China, with four scenarios set for the years 2030 and 2035 at P = 50% and P = 75% to derive reasonable water resource allocation schemes. The results show that the economic benefits range from 161.94 × 10⁸ to 212.74 × 10⁸ CNY, the water shortage rate is controlled between 1.38% and 10.86%, and COD emissions are maintained between 6.03 × 10⁴ and 6.91 × 10⁴ tons. Except for the 2030 drought scenario (P = 75%) with a coordination degree of 0.7847, classified as a medium coordination level, all other scenarios have coordination degrees greater than 0.8, indicating a good coordination level. The optimized allocation scheme can serve as a reference for the rational allocation of water resources in Jinzhong City. Moreover, the method proposed in this paper is a general approach that can be extended to other similar water-scarce cities with appropriate parameter adjustments, contributing to the sustainable development of urban water resources. Full article

Rapid economic development, accelerated urbanization, and agricultural modernization in eastern China have exacerbated pollution in rivers discharging into the sea, challenging regional ecological security and water resource sustainability. This study investigates ten main rivers in eastern China using monthly water quality and hydrological data from 2021 to 2023. Pollutant fluxes for permanganate index (${\mathrm{COD}}_{\mathrm{Mn}}$), ammonia nitrogen (AN), total phosphorus (TP), and total nitrogen (TN) were calculated, and their temporal and spatial variations were analyzed using descriptive statistics, two-way analysis of variance (ANOVA), and principal component analysis (PCA). Results show significant spatial heterogeneity, with the Yangtze (YAR) and Pearl Rivers (PER) exhibiting the highest fluxes due to high basin runoff and intense human activities. Seasonal variations significantly affect ${\mathrm{COD}}_{\mathrm{Mn}}$, TP, and TN fluxes, with summer runoff and agricultural activities enhancing pollutant transport. Moreover, flood periods markedly increase pollutant fluxes compared to non-flood periods. PCA further reveals that the pollutant flux patterns of YAR and PER are clearly distinct from those of the other rivers, indicating the joint influence of geographic conditions and anthropogenic activities. This study provides quantitative evidence for regional water environment management and offers crucial guidance for developing sustainable, differentiated pollution control strategies. Full article

The rapid pace of urbanization is contributing to ecological degradation and poses a threat to regional ecological security. Addressing these issues requires effective strategies to mitigate existing environmental challenges. Ecological networks, as the spatial foundation for ecosystem services, play a critical role in reducing environmental degradation. By reconfiguring the spatial relationship between human activities and natural ecosystems, anthropogenic pressures on land can be alleviated. However, most current research focuses on administrative boundaries, which limits spatial continuity and regional coordination. Therefore, constructing ecological networks from a cross-regional perspective is essential for integrated ecological management. This study uses the Yangtze River Delta Ecological Green Integration Demonstration Area as a case study. We construct a blue–green ecological network by applying ecological footprint analysis, Morphological Spatial Pattern Analysis (MSPA), landscape connectivity assessments, the Minimum Cumulative Resistance (MCR) model, and gravity modeling. Practical strategies for integrating the ecological network into territorial spatial planning are also explored. The key findings are as follows: (1) The demonstration area contains 33 ecological source areas, including 20 primary sources located near administrative boundaries and central lakeshore wetlands. A total of 333 ecological corridors were identified. First-grade corridors are primarily located in rural areas, traversing agricultural land and water bodies. (2) We recommend corridor widths of 200 m for first-grade corridors, 60 m for second-grade corridors, and 30 m for third-grade corridors. These widths are based on species characteristics and land use types, and are found to be conducive to species migration and habitat connectivity. (3) We propose the development of tourism landscape zones from a cross-regional perspective, leveraging existing ecological and cultural resources. The multifunctionality of corridors is redefined through the integration of ecological and social values, enhancing their spatial implementation. This framework provides a practical reference for constructing cross-regional blue–green ecological networks and informs spatial planning efforts in other multi-jurisdictional areas. Full article

The UN 2030 Agenda implicitly recognizes the crucial role of the agricultural land market in several Sustainable Development Goals, particularly those related to food security, environmental sustainability, and economic growth. However, the dynamics of agricultural land prices are highly complex, shaped by multiple economic, social, and environmental factors, making it essential to conduct a systematic analysis of the mechanisms driving their variability. This study aimed to identify the key factors influencing agricultural land prices, both at the microlevel (parcel) and the macroeconomic level (country). To achieve this goal, a systematic literature review was conducted using the PRISMA 2020 guidelines. The analysis highlighted how intrinsic factors (soil fertility, access to water resources, plot size, and location) and extrinsic factors (urban pressure, fiscal policies, demographic changes, and climate variations) interact in the determination of land prices. The results suggest that the growing demand for agricultural land, combined with competition from other land uses, is contributing to a significant variation in market values, with implications for the sustainability of the agricultural sector. This study provides a framework for investors, policymakers, and researchers, highlighting the need for more transparent land policies, incentives for sustainable land management, and tools to counter land price speculation. Full article