Water Bodies In Areas Research Articles

Assessing the Nexus Between Landscape Degradation and Flooding in the Niger River Catchment, Southeastern Nigeria: A 40‐Year Geospatial Dynamics (1992–2022)

ABSTRACTThis paper examines the relationship between landscape degradation and flooding in the Niger River catchment of Onitsha, Nigeria, over a 40‐year period (1992–2022), focusing on changes in land use and land cover characteristics. Satellite images were preprocessed and classified using Anderson's classification technique. Erdas Imagine GIS software was adopted to carry out change analysis for each of the classes generated. The Landsat images for all the years (1992, 2002, 2012, and 2022) were acquired for the months of July (wet season) and December (dry season) and analyzed. The trends in seasonal changes in land use and land cover characteristics were prominent in the wet season. This was significantly seen in changes for water body and vegetative area. Built‐up areas and open spaces indicated a decrease during the wet season compared to the dry season. The notable changes occurred in water bodies and vegetation across the studied years, peaking in 1992 with 1628.82 ha for water bodies and 8993.79 ha for vegetation. In 2012, these values were 2040.93 and 8977.5 ha. The largest seasonal shifts were in vegetative areas in 2012 and built‐up in 2022. After analyzing the geospatial data according to the classifications, the study uncovers a notable link between landscape degradation and increased flood susceptibility. Notably, the findings highlight that shifts in these landscape features during the wet season significantly impact flood occurrence, emphasizing the critical role of landscape degradation in exacerbating flood risks in the region.

Land use dynamics and ecosystem service valuation in the Sanmenxia Reservoir wetland of the Yellow River

The Sanmenxia Reservoir wetland (SRW) serves as a critical ecological buffer in the middle reaches of the Yellow River. Ongoing population growth and changes in land use have placed significant pressure on the wetland’s ecosystems. However, existing research has yet to establish a spatiotemporal analysis method to assess the impact of land use change on the ecosystem service value (ESV). This gap hinders the precise regulation and sustainable development of land resources. To gain a comprehensive understanding of the land use dynamics and ecological functions of the SRW, this study introduced a refined ESV evaluation method. This method revised the equivalent factors from spatial, temporal, and hydrological perspectives, with an emphasis on the impact of sediment discharge. Furthermore, the Patch-level Land Use Simulation (PLUS) model was employed to project the land use structure in 2030, and the corresponding ESV was analyzed. The study revealed the following: (1) Cropland constituted the primary land type in the SRW. Over the last two decades, the build-up area exhibited the most significant single land use dynamics, with the transformation of bare land to cropland spanning the widest range and largest area. (2) From 2000 to 2020, the ESV increased by 0.64 billion CNY, with the water body contributing almost all the increase. (3) The projected ESV for 2030 is 2.94 billion CNY, indicating an increase in ecological functions in the near future. Policy makers should recognizethe impact of land use change on ESV and implement measures to rebalance land use structure. While ensuring the preservation of cropland and the protection of lives and property, it is advisable to consider expanding the water body area to facilitate comprehensive sustainable development within SRW.

Distinctive water bodies surrounding lakes: An effective indicator for drought monitoring and assessment

The response mechanisms of surface water to drought and the potential and performance of water body changes in drought monitoring and assessment remain insufficiently elucidated. We take the Poyang Lake Basin, which suffers from drastic water body changes and frequent droughts, as a representative. Through integrating multisource data to extract long-term precise water bodies, we construct standardized water body area/number anomaly indices (SAAI/SNAI). Subsequently, we quantify the correlation and time lag response between SAAI, SNAI and drought. Our findings reveal that overall, water body area and number in the Poyang Lake Basin all exhibit a significant correlation with typical drought indices. Among them, the large water body area has a higher correlation coefficient with drought, making it a more effective indicator for drought monitoring. Water body changes of Poyang Lake surrounding area offer a more precise reflection of drought conditions than other sub-basins and exhibit greater sensitivity to drought. Meanwhile, water body area changes in Poyang Lake surrounding area lag behind meteorological drought by approximately half a month. And the basin’s water body area can typically respond with changes to some prolonged and severe hydrological droughts about 1 to 2 months in advance. We propose an integrated mechanism for drought monitoring and assessment informed by these conclusions and use actual drought events for qualitative validation. The results indicate that it is possible to assess water body drought conditions for the next approximately half month based on current meteorological drought conditions. Also, combining water body area changes with meteorological drought severity can aid in evaluating hydrological drought conditions for the following about 1–2 months. We extend our investigation to explore the universality of these phenomenon across eight shallow lakes globally characterized by significant water fluctuations. The results reveal that the water body changes in most of these lakes exhibit good potential for drought monitoring and assessment, and present a strong consistency with deep soil moisture, allowing for the accurate reflection of deep soil drought conditions. The lag response patterns between water bodies and drought in Dongting Lake, Hongze Lake, and Tonlé Sap Lake—also situated in the monsoon climate zone—are more similar to those observed in Poyang Lake. These distinctive lake water bodies can serve as an innovative indicator for drought monitoring and assessment, providing potential support for endeavors in drought prevention and mitigation.

Analysis of land use land cover change dynamics in Habru District, Amhara Region, Ethiopia

This study examines spatiotemporal changes in Land Use Land Cover (LULC) patterns within Habru District, Amhara Region, Ethiopia, between 1985 and 2021. Employing Landsat imagery and a supervised classification approach, we mapped six LULC classes: water body, settlement area, cultivated land, bare land, shrub land, and forest land. Ground control points (GCP) were obtained through field observations to ensured image accuracy. Complementing the remote sensing analysis, focus group discussions (FGDs) and key informant interviews were conducted to understand local perspectives on LULC changes. The analysis revealed significant LULC transformations over the study period. Between 1985 and 2021, there was a significant increase in cultivated land and settlement areas, which expanded from 12.27 % to 0.23 %–42.12 % and 2.58 % of the total area, respectively. Conversely, shrub and forest lands saw a marked reduction during the same period, declining from 71.52 % to 12.88 %–45.35 % and 7.06 % of the total area, respectively. Water body area showed a minor increase, while bare land exhibited negligible change. Agricultural land and settlement area expansion, population growth, land tenure insecurity, economic challenge, and climatic change were identified as key drivers of observed LULC changes. Our findings underscore the urgency of implementing multifaceted interventions to address these drivers and promote sustainable resource use practices. Such actions are critical for safeguarding Habru District's natural resources and ensuring the long-term viability of ecosystem services.

Ecosystem service value and ecological compensation in Qilian Mountain National Park: Implications for ecological conservation strategies

Qilian Mountain National Park (QMNP) is a critical ecological barrier and water conservation area in northwestern China. Its diverse ecosystems provide significant ecosystem services, yet the valuation of these services and their dynamic responses to land use/cover (LULC) changes and ecological protection measures require detailed investigation. This study employs an improved equivalent factor method, tailored to the specific ecosystem types and LULC patterns of QMNP, to evaluate the ecosystem service value (ESV) across different LULC types. Using an elasticity analysis model, the sensitivity of ESV to LULC changes from 1990 to 2022 was quantitatively assessed. The results indicate that the ESV of QMNP increased from 46.13 billion RMB to 50.97 billion RMB between 1990 and 2022, mostly due to the growth of grassland and forest areas. The primary route for increasing the region’s ESV is the conversion of desert to grassland, and this should be a major area of emphasis for next ecological conservation initiatives. Regulating services form the core of the ESV in QMNP, with climate and hydrological regulation contributing significantly to the overall ESV. Maintaining the stability of forest, wetland, and water body areas is crucial for sustaining the total ESV of QMNP. Through the application of carbon emission coefficients and ESV methods, the average range for long-term ecological compensation standards in QMNP is expected to be between 3.78 billion RMB and 28.28 billion RMB annually. Additionally, we explore the impacts of ongoing ecological protection mechanisms on enhancing ESV. There is a pressing need to formulate integrated policy frameworks that balance ecological conservation with sustainable economic development. The study also highlights the necessity of strengthening the protection and foundational research of grasslands and water bodies to enhance the ESV of QMNP. These insights serve as a foundation for potential planning and management strategies in QMNP, aiming to maintain and enhance its ecosystem functions and services, thereby contributing to broader regional and global ecological stability.

Integrated Assessment of Disturbed Ecosystems Using Remote Sensing Technique

Introduction. Today, there is a need for a shared vision of restoration of disturbed ecosystems, which is defined as “the process of stopping and reversing degradation, leading to improved ecosystem services and restoration of biodiversity.”Problem Statement. The assessment and restoration of disturbed ecosystems has become especially relevant for the Ukrainian society now, as warfare has caused large-scale changes in environment and both short-term and long-term consequences for ecosystems in Ukraine.Purpose. Assessment of ecosystems disturbed as a result of warfare impact by remote sensing.Materials and Methods. Multispectral satellite imagery, ground truth data and ecosystems characteristics of study area have been used. Remotely sensed data processing, geospatial modelling, and mathematical statistics have been applied.Results. A warfare impact on the ecosystems of Ukraine has been overviewed. Possibility of using remote sensing methods have been considered; their advantages and disadvantages have been generalized. A demo example of the described technique for assessing the ecosystem conditions along the E40 highway on the west of Kyiv has been shown with the use of multi-time satellite imagery of very high resolution (0.5 m on the ground) between May 2020 and March 2022. The analysis of the obtained maps allows us to assess short-term changes in land cover: a decrease in the area of water bodies, coniferous and leafy plants, an increase in the open soil area. The ecosystem conditions map of the studied area enables identifying plots of high risk.Conclusions. Integrated remote assessment of the condition of disturbed ecosystems and geospatial analysis of corresponding risks are useful tools for the territory management. Remote sensing techniques are particularly important in the context of largescale warfare. In many cases, only remote sensing techniques can provide information on the condition of ecosystems that areinaccessible or dangerous for ground-based research. Currently, the proposed approach has been elaborated and tested over other territories, different ecosystems and other data sources. Completed and tested integral geo-information technology will be relevant for the post-war recovery of the territory of Ukraine. Further research should be focused on building a pool of quantitative models for probabilistic assessment of the risk of disruption of various ecosystems under diff erent conditions, as well as on obtaining an array of statistical data to increase the reliability of the resulting maps.

Utilizing deep transfer learning to discover changes in landscape patterns in urban wetland parks based on multispectral remote sensing

Urban wetland parks are essential for protecting ecosystems and alleviating urban heat island effects. Owing to the impact of urban sprawl and human activities, habitats in wetland parks have become increasingly fragmented, evoking an urgent need to accurately monitor and analyze such changes. In this study, a transfer learning-based ResNet-18 method was proposed to classify the landscape patterns of urban wetland parks by integrating the advantages of remote sensing technologies, i.e., long-time series of Gaofen-2 and high-accuracy data of unmanned aerial vehicle remote sensing. The proposed method solves the dual problems of low precision and sparse sample data in landscape pattern classification. By employing the proposed method, we realized long-time-series, high-accuracy analysis of landscape pattern changes in a national wetland park. Our results showed that the overall accuracy was 90.69–97.96 % and Kappa coefficient was stable between 0.865 and 0.968, fully verifying the effectiveness and reliability of our method. We revealed a shrinking trend in the area of water bodies along with an expanding trend in the area of other land types. Thus, our findings reflect the significant impact of urban sprawl on the landscape patterns of wetland parks.

Study on the characteristics and scenario simulation of land use change in the Chaohu Lake Basin, China

Effectively evaluating the historical and future land use/cover change (LUCC) is significant for effective land use planning and management, ecological conservation, and restoration. Taking the Chaohu Lake Basin (CLB) as the study area, GIS technology and geographic detector were used to quantitatively analyze the change characteristics and driving factors of LUCC under the three periods in 2000, 2010, and 2020 of the CLB. This study aimed to comprehend the alterations that have transpired over the last two decades. In addition, the PLUS model was utilized to forecast LUCC trends under three scenarios: natural development, urban development, and ecological protection by 2030 in the CLB. The results suggest a significant decrease of the cultivated land area, while a considerable increase for the construction land area from 2000 to 2020 in the CLB. The expansion of the construction land area was mainly driven by the conversion of cultivated land area. Additionally, the slope was identified as the primary factor influencing LUCC, with q-values of 0.275, 0.266, and 0.258 in 2000, 2010, and 2020, respectively. The interaction between slope and soil type, distance to the trunk road and the secondary trunk road, and GDP was strong. The explanatory capacity of socioeconomic factors demonstrated a steady increase. The simulation results indicate that a decrease in cultivated land area and an increase in construction land area still occurred by 2030 in the CLB, particularly in the urban development scenario. Nonetheless, a notable deceleration of change was appeared in the ecological protection scenario. The alterations in forest and grassland areas were not significant. However, the water bodies area continued to enlarge, although the expansion was not substantial. The study results can provide policy references for the scientific management and long-term strategic planning of land resources in the CLB.

Impacts of land use changes on the spatiotemporal evolution of groundwater quality in the Yinchuan area, China, based on long-term monitoring data

Agricultural activities and rapid urbanization have significantly impacted groundwater quality, especially in semi-arid and arid regions. This study comprehensively evaluated the quality of phreatic and confined groundwater in the Yinchuan area, China, using long-term monitoring data from 1991 to 2018. Geospatial analysis model was employed to explore the spatiotemporal evolution of groundwater hydrochemistry. The effects of land use changes on groundwater quality were assessed using correlation analysis and a multiple linear regression model (MLR). The findings indicate significant temporal variations in groundwater quality, with phreatic water consistently exhibiting high salinity and hardness. The groundwater quality indices for phreatic water were frequently more polluted than confined water. From 1991 to 2018, the hydrochemical composition of phreatic water evolved from HCO3-Mg and HCO3•SO4-Mg to more complex forms such as HCO3•SO4•Cl-Mg and HCO3•Cl-Mg. In contrast, confined water predominantly maintained its HCO3-Mg type and HCO3•Cl-Na (Na•Mg) type water. Urban land had rapidly expanded in the past three decades, increasing by 318.75% compared to 1991. The water body and urban area diminished the quality of phreatic water. High salt water in increase of TDS, Cl–, SO42–, Mn, TH, NO3–, F–, and Fe into phreatic water. NO3–, NH4+, and F− in phreatic water could be impacted by human and industrial activity in urban areas. This study provides valuable insights for local decision-makers to effectively manage groundwater resources and solve issues of groundwater scarcity and water quality problems in arid and semi-arid locations.

A study on the response of waterbird diversity to habitat changes caused by ecological engineering construction

Wetland degradation is a major factor in the decline of biodiversity. Ecological engineering construction efforts, such as water diversion, have been the main method of wetland restoration. To reveal the effects of biodiversity conservation and ecological engineering construction in the semiarid regions of China, waterbird surveys were carried out 2 years before and 8 years after the construction of the ecological engineering project discussed in this study. The relationships among waterbirds and habitat landscape patterns, hydrology and vegetation conditions were analyzed. The impacts of ecological engineering on habitats and waterbird diversity were revealed. The results showed that (1) there were significant changes in land use, hydrological distributions and vegetation cover in the study area before and after the construction of the ecological project. The quality of waterbird habitats after the construction project was better than that before construction. However, there were fluctuating conditions. (2) The areas of water bodies and marshes were positively correlated with the number and diversity of waterbirds. However, increases in arable land, forestland, grassland and saline land can stress rare waterbirds. Changes in water levels, water body areas and vegetation cover in the conservation area all directly affect the availability of waterbird habitats, which can affect waterbird diversity. The wetland water level is the most important impact factor. (3) The annual water diversion volume in the study area is 5.00 × 107 m3. When the water level is maintained at approximately 1.5-2.5m, the number of waterbirds remains stable. This study can provide scientific guidance and a methodological basis for the construction of ecological projects with waterbirds as protected targets.

How does urban form explain water cooling effect heterogeneity: A case study in Wuhan, China

Water bodies in urban areas are considered to be natural and effective cooling factors that can help mitigate the urban heat island (UHI) effect. Previous studies highlighted the cooling effect is determined by the size and landscape of the water bodies. However, it is unclear how the urban form surrounding water bodies influences the water cooling effect received by human activity space. Using high resolution data and a multiple linear regression model, the effect of various 2D/3D urban form factors on the average water cooling intensity (AWCI) and water cooling intensity (WCI) at the fine scale were examined in Wuhan City on hot days. We further verified the spatial heterogeneity of the relationship between urban form factors and WCI according to the distance to and size of adjacent water bodies. The AWCI of the entire surrounding area were correlated with building morphology indicators. Urban form indicators effectively explained the variations of WCI at the fine scale, indicating that a mixture of large building volume density (BVD) with small building density (BD), and an aggregated impervious surface area (ISA) with a complex shape were conducive to WCI. Additionally, building morphology had a larger impact on the cooling effect around small water bodies and in the outer buffer area of water bodies. In comparison, the cooling effect of the area surrounding large water bodies was more affected by the landscape of the ISA. We therefore propose a differentiated urban planning strategy to take full use of the limited water cooling effect.

Assessing tropical cyclone impacts in coastal Bangladesh: A change detection analysis on cyclone Bulbul using geospatial analysis and remote sensing techniques

The coastal regions of Bangladesh are highly susceptible to the impacts of tropical cyclones, which frequently pose substantial challenges for disaster management. This research aimed to analyze the immediate consequences of significant catastrophic disasters imposed on coastal regions using geospatial techniques. Cloud-free satellite images and a support vector machine learning algorithm were utilized to examine the outcomes of Land Use and Land Cover (LULC) in the pre- and post-cyclone phase for assessing disaster impact. This study found that after the cyclone Bulbul, 45.08 km2 of land features were changed. It also showed agriculture, bare land, dense vegetation, and settlement areas have decreased by about 4.75 km2, 5.55 km2, 4.56 km2, and 7.72 km2, respectively. Instead, the body of water grew at a terrible rate of 22.49 km2 in areas turned into water body areas. Cyclone made a considerable impact by increasing the waterbody in this study area by flooding, mainly the southern portion, due to the changing process of land characteristics, which increases (waterbody) and reduces (agricultural, dense vegetation, barren land, settlement areas). The accuracy of the analysis was supported by the kappa coefficient. The results underscore the vulnerability of the coastal region and emphasize the need for effective post-cyclone recovery strategies. The study hamper valuable insights into the dynamic changes in the landscape following a cyclone, shedding light on the socio-economic and environmental implications. Further research is recommended to explore the long-term impacts of cyclones on coastal ecosystems and communities, considering the changing climate patterns.

Spatio-temporal Pattern of Ecosystem Service Value Evolution in the Yihe River Basin in the Context of Land Use Change

In this study, the modified equivalent factor method was applied to account for the long time series ecosystem service value （ESV） of the Yihe River Basin from 1975 to 2020 in the context of land use change, and the cold hot spot analysis and topographic position analysis methods were introduced to explore the characteristics of its spatial pattern. The results showed that： ① From 1975 to 2020, the land use type of the Yihe River Basin was dominated by arable land, and the land use changes were characterized by the rapid decrease of arable land and the continuous expansion of construction land, a slight increase in the area of forest land and grassland, a contraction of the water body area, and little change in the area of unused land. ② The modified equivalent factor method was more suitable for accounting for the ESV in the basin. From 1975 to 2020, the overall ESV of the basin showed an upward spiral trend （33.369-33.816 billion CNY）, dominated by the regulating services. The ESV of arable land was the highest with a decreasing trend, whereas the ESV of unused land was the lowest. ③ In the horizontal spatial pattern, the hot spot of ESV was near mountains and reservoirs, and the cold spot of ESV was near urban areas. In terms of vertical spatial patterns, with growing topographic gradient, vertical changes in ESV for all land use types showed an increasing trend followed by a decreasing trend. The results of the study revealed the spatial and temporal patterns of ecosystem service values in the Yihe River Basin in the context of land use change and provide a scientific basis for optimizing the land use structure and spatial pattern and enhancing ecosystem services.

Human activities and ecosystem health: A historical analysis of Poyang Lake

Urbanization, industrialization, land development, and other human activities have led to ecological issues such as shrinking lake wetlands, fragmented cropland, and reduced biodiversity. Taking the Poyang Lake urban agglomeration as the study area, the textual analysis method was used to analyze the typical facts of the historical succession of human activities since 1949, and then the index method and the spatial analysis method were adopted to characterize the spatial and temporal evolution of the ecosystem health and human activities in the period of 2003–2020. On this basis, the spatial spillover effects of human activities on ecosystem health were investigated based on the spatial Durbin model in four dimensions. The results of the study show that since 1949, human activities in the Poyang Lake area have gone through the management path from “agricultural retreat and fishery advancement” and “dike reclamation” to “sand ban” and “returning the lake”. Ecological protection has gone through the sublimation from “enlightenment” to “full implementation” to “strengthening and upgrading”. The ecosystem health of Poyang Lake urban agglomeration from 2003 to 2020 has been in the range of 0.37709 ∼ 0.3709 ∼ 0.3709. 0.37709 ∼ 0.48485, with the spatial characteristics of “low in the center and high in the periphery”. The city expansion and agricultural activities in the county are generally distributed in the pattern of “high center, low periphery”, while the spatial distribution of water body area is characterized by “near-lake” and “near-river”, and the newly registered enterprises show a change from “point” to “surface”. The spatial distribution of water body area is characterized by “proximity to the lake” and “proximity to the river”, and the newly registered enterprises show changes from “point” to “surface”. There is a significant spatial competition effect on the effects of city expansion on ecosystem health, while there is a significant negative spatial collaboration effect on the effects of industrial activities, and agricultural activities show a significant spatial spillover effect. The results of the study can provide more detailed empirical support for the regulation and management of ecosystem health in global lakeside urban agglomerations.

Integrating key ecosystem services to study the spatio-temporal dynamics and determinants of ecosystem health in Wuhan’s central urban area

The central areas of many Chinese cities have experienced large-scale urbanization in recent decades, a trend that is affecting the quality of life of residents and posing challenges to the sustainable development of urban ecosystems. Hence, it is vital to conduct assessments of urban ecosystems’ health conditions to ensure their sustainability. In this study, the spatial and temporal dynamics of ecosystem health in the central city of Wuhan were analyzed using the Vigor-Organization-Resilience-Service (VORS) model. The sensitivity of ecosystem health at different scales was also investigated using hierarchical health assessment delineation and random forest regression methods. The results showed that the composite index of ecosystem health has been declining since 2000, highlighting the negative impacts of shrinking ecological space, declining service capacity and urban expansion. Health zoning divides areas into five categories. Meanwhile, the health zones are located in areas of dense shrubs, cropland and water bodies on the edge of the central city, while the weak zones are mainly in the core of the city, which is 99.33 % impervious surface. The main factors influencing ecosystem health, including impervious surface area, water bodies and topography, vary from region to region. The study proposes targeted ecological management strategies for different health zones in Wuhan, emphasizing ecosystem protection and providing guidance for sustainable urban development.

Calculation of the Optimal Scale of Urban Green Space for Alleviating Surface Urban Heat Islands: A Case Study of Xi’an, China

Research has demonstrated that urban green spaces play a crucial role in mitigating the severe urban heat island (UHI) effect. However, existing studies often suffer from limitations such as the neglect of the cooling effect of water bodies within the green spaces and incomplete considerations of the overall cooling effect. These limitations may lead to inaccuracies in the research findings. Therefore, the present study takes the city of Xi’an as a case study to explore the optimal green space size for achieving efficient cooling. The results indicate that (i) urban green spaces exhibit robust cooling effects, with variations observed among the various types; (ii) for community parks without water, and for street gardens, the optimal areas of these green spaces are 3.44 and 0.83 hectares, respectively; (iii) for community parks with water, the area of internal water bodies should ideally be maintained at around 29.43% of the total green space area in order to achieve an optimal cooling efficiency. In conclusion, this study introduces a new perspective and new optimization methods for urban green space planning, thereby offering scientific guidance to urban planners in formulating effective development and management policies and urban planning schemes.

Seguimiento de los cambios en el uso del suelo y la cobertura del suelo utilizando tecnicas de teledeteccion y SIG en la Isla de Phu Quoc, Provincia de Kien Giang, Vietnam

The changes in land use and land cover (LULC) are among the primary drivers of global environmental changes in many developing countries. In this study, LULC changes were assessed on Phu Quoc Island, located in Kien Giang province, Vietnam, from 2001 to 2022. The study utilized remote sensing and Geographic Information System (GIS) technology using Landsat images for the years 2001, 2009, and 2022. Image classification for each year was conducted through supervised classification using a maximum likelihood classifier, with the main LULC classes being forests, bare land, agricultural areas, water bodies, and built-up areas. The accuracy of the classification was evaluated using the kappa coefficient, achieving values consistently above 0.8 for all three images. Over the 20-year period (2001-2022), the area of forest, agriculture, and water bodies decreased by 14.90 km2, 30.96 km2, and 0.64 km2, respectively. Meanwhile, the areas of bare land and built-up areas increased by 22.22 km2 and 24.28 km2, respectively. Additionally, this study employed the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Built-up Index (NDBI) to quickly assess LULC changes, obtaining results consistent with the supervised classification. The findings underscore the importance of closely monitoring LULC changes to facilitate effective natural resource management and maintain a sustainable environment.

Comparative analysis of land use changes modeling based-on new hybrid models and CA-Markov in the Urmia lake basin

Land use change is one of the most significant environmental issues in many countries and is the main reason for ecosystem changes. This issue is one of the most important environmental crises in Iran due to the lack of planning and inappropriate human use of the natural environment. Many parts of Iran, especially the Urmia Lake basin, are involved in challenging land use changes. The trend of land use changes extracted from Landsat images in the Urmia lake basin with overall accuracy and Kappa coefficient of more than 85 % and 80 % respectively shows that during the 32-year period (1989–2021) agricultural lands, built-up lands and barren lands respectively 3330.83 km2, 466.86 km2 and 5325.8 km2 have increased in area. On the other hand, the areas of vegetation and water bodies decreased by 6625.79 km2 and 2497.7 km2, respectively. The current trend of land use changes in Urmia basin based on all models of Markov chain-Multi Criteria Evolution-Cellular Automata (MC-MCE-CA), Markov Chain-Multilayer Perceptron-Cellular Automata (MC-MLP-CA), Markov Chain-Sim Weight-Cellular Automata (MC-SW-CA), Markov Chain–Logistic Regression-Cellular Automata (MC-LR-CA) indicate the continuation of changes until 2037. Meanwhile, based on the most accurate models such as MC-MLP-CA and MC-LR-CA models, agricultural lands will increase by 1436.60 km2 and 1258.33 km2, built-up lands by 75.23 km2 and 65.52 km2, and barren lands by 808.94 km2 and 856.90 km2 respectively. Also, the vegetation lands will be reduced by 1890.64 km2 and 1755.31 km2 and water bodies by 430.13 km2 and 425.44 km2. In general, the results showed that MC-MLP-CA, MC-LR-CA, MC-SW-CA, MC-MCE-CA models with Overall Kappa 89.89, 87.09, 84.52 % and 84.84 and Percent of Correctness 93.65, 93.09, 91.52 and 91.77 respectively, with higher accuracy than the CA-Markov model (Overall Kappa = 81.49 % and Percent of Correctness = 87.49 %) are more effective for land use changes modeling.

A novel approach for quantifying the influence intensity of urban water and greenery resources on microclimate for efficient utilization

Climate changes have led to increasing global energy consumption, detrimental to the sustainable development of society. Urban blue-green infrastructure (UBGI) can improve urban microclimate. However, influence intensity of UBGI on microclimate has not been quantified deeply to improve the use efficiency of water and greenery resources. To solve research deficiencies, this study numerically simulated the UBGI for 44 scenarios with different resource configurations (various water body areas and greenery coverages) in summer. Based on simulations, this study developed novel mathematical models of UBGI thermo-environment (BGTE) to quantify influence intensity of UBGI. The results indicated that daytime synergies of UBGI first increased and then decreased with time. The significance intensity of the influence of time (t), water body area (Sw), tree coverage rate (TCR), shrub coverage rate (SCR), and grassland coverage rate (GLCR) on the synergy of water and greenery was quantified by artificial neural network: t (39.4 %), Sw (22.6 %), TCR (22.0 %), SCR (13.2 %), and GLCR (2.8 %). To make the overall effect of UBGI on microclimate relatively efficient, Sw should be less than 10,000 m2, SCR should be greater than 65 %, and TCR should be close to 15 %. This research provides practical ideas for efficient use of water and greenery resources.

Analysis of Changes in Water Body Area in Southwest, China Based on GEE

It is of great significance for policymakers to develop management strategies for water resource regulation, habitat protection and wetland restoration. Based on the Google Earth Engine platform, this study extracted remote sensing data of water quality change in Southwest China in the past 20 years, combined with ArcGIS for spatial analysis, and used M-K trend test and mutation test to analyze the long-term temporal variation of water bodies in Southwest China. The analysis shows that the water area in Southwest China increased every five years from 2000 to 2020, but the growth rate changed, while the growth rate slowed down from 2010 to 2020, and the increase mainly occurred in the central and western regions. The results show that in the past 20 years, the water surface area in Southwest China has shown a statistically significant increasing trend, especially after 2020, this trend is more statistically significant. This study can provide a theoretical basis for the protection of water environment in Southwest China.