Water Bodies In Areas Research Articles

Identification and Prediction of Land Use Spatial Conflicts in Urban Agglomeration on the Northern Slope of Tianshan Mountains Under the Background of Urbanization

In past decades, urbanization has entered a phase of rapid development, resulting in an intensified utilization of land resources. The finite nature of these resources has led to increased pressure on land availability, giving rise to a phenomenon known as land use conflict. This conflict is particularly evident in the frequent conversion of land categories, with urban impervious surfaces increasingly encroaching upon forests, grasslands, and agricultural land. Such encroachments trigger a series of land use conflict issues, which subsequently impact the function and structure of regional ecosystems. This paper analyzes the spatial and temporal changes in land use and land cover (LULC) within the urban agglomeration on the northern slope of Tianshan Mountain. It measures and evaluates the spatial and temporal evolution of land use conflicts in the study area from 1990 to 2020, utilizing conflict-related theories and the landscape risk evaluation model. Additionally, the paper explores the spatial and temporal dimensions of land use conflicts under three scenarios—natural development (ND), cultivation priority (CP), and ecological priority (EP)—for the years 2030 and 2050, informed by the Future Land Use Simulation (FLUS) model. The results indicate that unused land constitutes the predominant land use type, accounting for over 50% of the total area. The areas of cultivated land, water bodies, and urban land are experiencing an increasing trend, while the areas of forestland, grassland, and unused land are witnessing a decreasing trend. The level of land use spatial conflicts during the study period showed a decreasing and then increasing trend, with an overall upward trend and an increase in the average value of 0.03. In terms of the proportion of spatial units, mild and general conflicts exhibited a decreasing trend, with reductions of 4.21% and 2.95%, respectively. Conversely, the proportion of medium conflicts increased significantly, rising by 7.33%, while severe conflicts experienced a slight increase of 0.23%. Under the ND, CP, and EP scenarios, the spatial and temporal dynamics of future land use conflicts varied. However, the study area was predominantly characterized by general conflicts in both 2030 and 2050. In 2030, the proportions of spatial units experiencing general conflicts in the three scenarios are projected to be 61.20%, 60.39%, and 57.51%, respectively. In comparison, these proportions are projected to be 59.24%, 62.70%, and 56.29% in 2050, respectively. The anticipated future changes in land use spatial conflicts vary across different scenarios. Notably, the ND scenario indicates a rising conflict level in the study area over the next 30 years, with an overall increase of 0.03 in the mean value. In contrast, the changes in the index under the CP and EP scenarios are relatively stable.

Land use and landscape pattern changes in the Fenhe River Basin, China

The composition and pattern of ecosystems play a crucial role in determining the overall condition and spatial variations of ecosystem services. In this study, we explored the Normalized Difference Vegetation Index (NDVI), six land use/land cover change (LULC) types, and their landscape patterns to reflect spatial-temporal dynamics from 2010 to 2020 in the upper and middle reaches of the Fenhe River Basin. The trend analysis of Mann-Kendall tests was used to assess the NDVI variation of each pixel over the past decade. Shannon’s Diversity Index (SHDI) was used to quantify the complexity of the landscape pattern of local LULC. Meanwhile, the spatial-temporal dynamic variations of vegetation NDVI and six LULC types were illustrated using geographic mapping methods. The results were presented as follows: (1) From 2010 to 2020, vegetation cover increased, with an annual NDVI increment of 0.003 (P < 0.001). Spatially, there was a significant increasing trend in NDVI, particularly in high-altitude mountainous areas where the vegetation cover mostly consisted of forests or grasslands. However, there was no significant change in vegetation cover in the low-lying urban agglomeration area. (2) During the period from 2010 to 2020, there was a significant decrease in the area of water bodies and wetlands, the rate of decrease slowed from 2015 to 2020. Specifically, the percentage of decrease from 2010 to 2015 increased by more than 14%. This proportion exceeded 30% when compared to the final governmental ecological management goal set during the 13th Five-Year Plan Period (2016–2020). (3) During the same period, the SHDI of LULC exhibited heterogeneous characteristics. In the high-altitude areas near the river basin boundary, SHDI values were below 1.0. Conversely, in the low-altitude plains and urban areas with frequent human activities, SHDI values exceeded 1.0, reaching above 1.5 in urban areas. This study provides a scientific reference for the construction and management of the ecological environment in the Fenhe River Basin, along with practice insights for ecological protection and high-quality development in the Yellow River Basin.

Monitoring Environmental Degradation and Spatial Changes in Vegetation and Water Resources in the Brazilian Pantanal

Diagnosing climate variability and environmental change in floodable regions is essential for understanding and mitigating impacts on natural ecosystems. Our objective was to characterize environmental degradation in the Brazilian Pantanal by identifying changes in vegetation and water cover over a 30-year period using remote sensing techniques. We evaluated surface physical–hydric parameters, including Land Use and Land Cover (LULC) maps, Normalized Difference Vegetation Index (NDVI), Modified Normalized Difference Water Index (MNDWI), Normalized Difference Moisture Index (NDMI), and precipitation data. There was a decrease in the area of water bodies (−9.9%), wetlands (−5.7%), and forest formation (−3.0%), accompanied by an increase in the area of pastureland (7.4%). The NDVI showed significant changes in vegetation cover (−069 to 0.81), while the MNDWI showed a decrease in water surface areas (−0.73 to 0.93) and the NDMI showed a continuous decrease in vegetation moisture (−0.53 to 1). Precipitation also decreased over the years, reaching a minimum of 595 mm. Vegetation indices and land use maps revealed significant changes in vegetation and loss of water bodies in the Pantanal, reinforcing the need for sustainable management, recovery of degraded areas, and promotion of ecotourism to balance environmental conservation and local development.

AqUavplant Dataset: A High-Resolution Aquatic Plant Classification and Segmentation Image Dataset Using UAV

Aquatic vegetation species are declining gradually, posing a threat to the stability of aquatic ecosystems. The decline can be controlled with proper monitoring and mapping of the species for effective conservation and management. The Unmanned Ariel Vehicle (UAV) aka Drone can be deployed to comprehensively capture large area of water bodies for effective mapping and monitoring. This study developed the AqUavplant dataset consisting of 197 high resolution (3840px × 2160px, 4K) images of 31 aquatic plant species collected from nine different sites in Bangladesh. The DJI Mavic 3 Pro triple-camera professional drone is used with a ground sampling distance (GSD) value of 0.04-0.05 cm/px for optimal image collection without losing detail. The dataset is complemented with binary and multiclass semantic segmentation mask to facilitate ML based model development for automatic plant mapping. The dataset can be used to detect the diversity of indigenous and invasive species, monitor plant growth and diseases, measure the growth ratio to preserve biodiversity, and prevent extinction.

Evaluating and predicting the impact of land use and land cover change on land surface temperature in Lac Duong district, Lam Dong province, Vietnam

Land use and land cover (LULC) change is a key factor influencing land surface temperature (LST) dynamics. This change reflects partly global warming and climate change at local and regional scales. This study aimed to evaluate the effect of LULC on LST change in Lac Duong mountainous district, Lam Dong province in the past 10 years (2013 - 2023), and predict the LST change in 2030. The study used satellite image data from Landsat 8 and 9 OLI to build LULC and LST maps and used the CA-ANN model to predict the LST map. The results showed that the forest land had the LST below 25°C, with the below 20°C LST area correlated negatively with the forest land area, while 20 - 25°C LST correlated positively, especially at the temperature of 22 - 25°C (R2 = 0.97). The 22 - 25°C and 30 - 35°C temperature levels (R2 = 0.76 and R2 = 0.86) correlated sharply with the crop land area. The LST levels between 30 - 40°C reflected the built-up land and bare land with the highest correlation of R2 = 0.68 and 0.88, respectively. The LST level 20 - 22°C represented the water body area (R2 = 0.87). The LULC changes had an impact on the LST change in the past 10 years in Lac Duong district. While the forest land area decreased slightly by 0.5%, the cool LST area fell considerably by 10.5% compared to 10 years ago. An almost doubling of the cropland area also led to a doubling in the 25 - 35°C LST areas. In addition, the 35 - 40°C LST level started to happen in several regions. The LST change was predicted to keep increasing in 2030. The temperature was predicted to increase by 2 - 3°C with a maximum temperature of 42°C.

Spatio-temporal variations of the LUCC of the Djoudj National Bird Sanctuary in the past 40 years and its sustainable development

Djoudj National Bird Sanctuary, as a UNESCO natural heritage site, is a critical habitat for migratory birds along the East Atlantic Flyway (EAF). The bird habitat has undergone the dramatic variations of the Land Use and Land Cover Change (LUCC) under the influence of climate change and human activities, posing a serious threat to the survival of migratory birds along the EAF. In order to explore the spatio-temporal variations of LUCC in Djoudj National Bird Sanctuary during 1984 to 2023, this study employs multitemporal satellite image data to extract the LUCC of this heritage site and adjacent region, and comprehensively analyze the impact factors induced the variations of LUCC. Our results show that it went through two stages of the significant change in LUCC over the past 40 years. The first stage of significant change is from 1984 to 1990, when the areas of soil land and saline soil land had largely transformed into water bodies, vegetation, and wetlands. The areas of soil and saline soil land were decreased by 28.86 % and 8.96 %, respectively. Meanwhile, the areas of wetland, water body and vegetation increased to 30.53 %, 4.92 % and 2.37 %, separately. The second stage of significant change in LUCC is from 2000 to 2010, while the area of vegetation (including the invasive plants) increased significantly to 54.02 %, and the areas of water bodies, wetlands, and saline soil areas decreased to 6.19 %, 10.37 %, and 10.05 % respectively. At the same time, the area of agricultural land around the heritage site rapidly increased from 13.292 km2 in 2006 to 114.2603 km2 in 2023. These significant variations of LUCC led to a decrease in the number of migratory birds, and the Djoudj National Bird Sanctuary had been listed as List of World Heritage in Danger twice by the World Heritage Committee. The major factors contributing to these significant changes in LUCC are mainly caused by human activities, such as the construction of the Diama Dam and improper use of upstream of the dam, as well as the expansion of agricultural land around the heritage site. Thus, we suggest that the heritage administrative authorities should make relevant measures to scientifically minimize the impact of human activities on ecosystem of the heritage site, and conduct regularly an integrated “space-to-ground” monitoring and assessment of water usage of the dam, controlling of invasive plants, strictly regulating the expansion of agricultural land within the heritage site and adjacent region.

TREATMENT METHODS FOR BITUMEN POLLUTED WATER(BPW) - A REVIEW

This review is set to answer the question about current and alternative treatment methods available for treating Bitumen000. 12021Polluted Water (BPW). Bitumen is a complex form of hydrocarbon with a higher viscosity than crude oil preventing it from flowing under natural conditions. BPW is formed due to bitumen seepage from underground reservoirs causing contamination of land and waterbodies in areas where the deposit is untapped. Another wastewater from bitumen is the Bitumen Wastewater (BWW) which is formed from bitumen extraction and processing, though this review centered on bitumen-polluted water BPW, studies revealed that BWW exhibits similar characteristics of floatable solids, high levels of salt and taste, colour, hardness of water, high Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) levels, toxic metals: lead, cadmium and dissolved petroleum hydrocarbons: Benzene, Toluene, Ethylbenzene, Xylene (BTEX). It has been reported that these pollutants were recalcitrant, persistent in biodegradation, and required many years to denature. This review summarized treatment methods for bitumen polluted water and by extension BWW from five aspects, which contain flotation, filtration, coagulation, biological treatment, and combined technology. Further, it addressed modifying the existing Bitumen Polluted Water Treatment System (BPWTS) with the possibility of scaling it up to treat more volume of BPW to meet water treatment demand in the bitumen-rich areas.

Air PM10,2.5 Removal by Urban Green Space Under Urban Realistic Stressors

Urbanization has significantly altered the ecological resources, functions, and services, thereby imposing specific constraints on particulate matter (PM) mitigation through green spaces. To investigate the effect of green spaces on mitigating PM10,2.5 under multiple urban stressors, this study employed combined remote sensing imagery and small-scale quantitative measurements to identify the PM within green space and street tree, and their PM differences with the square underlying surface according to a continuous scale of 60~3000 m. The results indicated that urban stressors significantly influenced air PM10 and PM2.5 mitigation, with stressors LST (land surface temperature) and RD (traffic road density) as key stressors on air PM10, while LST, ISA (impervious surface area), BH (building height), NDVI (normalized difference vegetation index), GA (green space area), and WA (water body area) were key stressors on air PM2.5. Furthermore, stressors exhibited a significant scale effect on air PM10,2.5 mitigation; for air PM2.5, stressors ISA, RD, BH and BD (building density) had a notable impact on air PM2.5 mitigation at 1500~3000 m scales, while NDVI, GA, and WA showed a significant impact at 450~600 m. For air PM10, stressors ISA, BH, NDVI, and GA revealed a continuous scale effect, with the key scales occurring at 450 m and 3000 m. In summary, urbanization stressors can combine to affect air PM10 and PM2.5 mitigation by green spaces, especially at different spatial scales, to provide practical guidance for urban planning.

Spatial-Temporal Variations and Severity of the 2020 Catastrophic Floods in the Yangtze River Basin from Sentinel-1 SAR Data

Flood is one of the most frequent natural disasters in the Yangtze River Basin. Flood risk evaluation is of great social significance, especially for large hydrological systems. Rainfall is both temporal and spatial, influencing surface hydrological activities. The water body range is the final outcome of a flood and can be observed from synthetic aperture radar (SAR) images under any weather condition. A flood severity evaluation model is proposed to quantitatively evaluate the flood based on water body range from area disparity and flood duration. Large hydrological objects usually span a wide range and have significant differences. This results in different initial water areas in each region. This approach addresses the issue through normalization processing. In this paper, Sentinel-1 data are used to extract the temporal water body using the adaptive bimodal method, and the water level data were also incorporated to improve the observation frequency for water area. The flood severity evaluation approach can be used to assess flood risk between any region of large hydrological systems or any flood event, regardless of their regional spatial differences and rainfall duration differences. The results show that: (1) In general, the average water body area in 2020 was 20.40% larger than it was in 2019, and the daily water body areas in 2020 were all greater than the average of 2019 with 71.36% of the days in 2020 having an area greater than the maximum in 2019. The flood severity in 2020 was 1.75 times as much as that of 2019; (2) Reach performance indexes in 2020 were in order of Yueyang (2.21) &gt; Jiujiang (2.04) &gt; Hankou (1.44) &gt; Chizhou (1.32), which were inconsistent with the spatial site; (3) Flood event impact indexes in 2020 were in order as No.2 (1.64) &gt; No.3 (1.61) &gt; No.1 (1.44) &gt; No.4 (1.17) &gt; No.5 (1.15); (4) The flood was more likely the result of cumulative rainfall for 30 days.

Enhancing Bird Diversity in Urban Parks: Insights from the Futian Mangrove Ecological Park, Shenzhen

Small urban parks and green spaces, serving as essential recreational venues for city residents, also play a vital and irreplaceable role in maintaining urban biodiversity. It is of great importance to design and plan these areas in a way that integrates multiple habitats for various species while accommodating residents’ usage. This study, carried out at the Futian Mangrove Ecological Park located in Shenzhen, Guangdong Province, China, chose birds as indicator species to assess biodiversity within the park. Site inventory was undertaken from May to September 2022 and from October 2022 to April 2023. We quantitatively described the park’s habitats by examining primary environmental factors, along with 3 primary environmental factors and 11 secondary factors. A correlation analysis was then performed between these factors and bird diversity to gain insights into birds’ habitat preferences across different habitat types and at a finer scale of plant communities. Furthermore, bird clusters in the study case were categorized by foraging guilds and foraging patterns, and their distributions were studied at both the habitat patch scale and the plant community scale. Our findings reveal that, at the habitat patch scale, water surface area and grass coverage significantly positively impact bird diversity. At the plant community scale, plant communities with different structural characteristics vary in their importance to bird clusters with distinct characteristics. In areas with high human disturbance, shrub coverage is crucial for bird habitat protection. Additionally, we discovered that the impact of anthropogenic sound differs among bird species, highlighting the complexity of human disturbance factors on bird habitat preferences. Accordingly, we proposed several design recommendations aimed at enhancing bird diversity in parks, including increasing water body areas, reducing the distance between habitats and water surfaces, enhancing herbaceous plant coverage, and controlling anthropogenic sound.

An attention-based multiscale few-shot network for water body extraction from GF-2 satellite imagery

The core to water resources mapping is water body extraction, a pivotal technique employed to distinguish areas of water bodies from land and other regions. Presently, water body extraction methods relying on remote sensing images predominantly utilize supervised learning approaches. However, these methods are limited to fixed areas and demand a substantial amount of manually annotation data for the accurate identification of water bodies. This paper introduces a novel perspective by treating water body extraction as a few-shot semantic segmentation task, aiming for generalization across diverse geographic regions. This paper proposes a hierarchical atrous spatial pyramid pooling (ASPP) attention module to enhance the model’s extraction capabilities in multi-scale water bodies to highlight the characteristics of water bodies at different scales. Quantitative evaluation on test dataset shows that our method achieves average precision of 94.01%, average recall of 90.81%, average IoU of 90.14%, and average F score of 91.31%. Comparative analyses also prove that our method can extract water bodies across geographical areas, providing new ideas for water resources mapping.

Dynamics of Changes in the Surface Area of Water Bodies in Subsidence Basins in Mining Areas

The Silesian Upland in southern Poland is known as a place where subsidence processes induced by mining activities occur in an area of nearly 1500 square kilometres, with many water bodies that formed in subsidence basins. This study concerned the dynamics of changes in the occurrence, boundaries and area of water bodies in subsidence basins (using orthoimagery from 1996 to 2023), as well as the assessment of the factors underlying the morphogenetic and hydrogenetic transformations of these basins. Within the subsidence basins covered by the study, water bodies occupied a total area that changed from 9.22 hectares in 1996 to 48.43 hectares in 2003, with a maximum of 52.30 hectares in 2009. The obtained figures testify to the extremely dynamic changes taking place in subsidence basins, which are unprecedented within such short time intervals in the case of other morphogenetic types of lakes and anthropogenic water bodies (for instance, from 1996 to 2003, the basin of the Brantka water body in Bytom underwent a more than two-fold change in its area, with RA values in the range of 54.4% to 131.9). A reflection of the dynamics of short-term changes in the water bodies in question in the period from 1996 to 2023 is the increase in the water area of the three studied water bodies, which was projected by linear regression to range from 0.09 hectares/year to 0.56 hectares/year. The area change trends, as determined by polynomial regression, suggest a slight decrease in the water table within the last few years, as well as within the next few years, for each of the studied basins.

Vegetation and carbon sink response to water level changes in a seasonal lake wetland.

Water level fluctuations are among the main factors affecting the development of wetland vegetation communities, carbon sinks, and ecological processes. Hongze Lake is a typical seasonal lake wetland in the Huaihe River Basin. Its water levels have experienced substantial fluctuations because of climate change, as well as gate and dam regulations. In this study, long-term cloud-free remote sensing images of water body area, net plant productivity (NPP), gross primary productivity (GPP), and Fractional vegetation cover (FVC) of the wetlands of Hongze Lake were obtained from multiple satellites by Google Earth Engine (GEE) from 2006 to 2023. The trends in FVC were analyzed using a combined Theil-Sen estimator and Mann-Kendall (MK) test. Linear regression was employed to analyze the correlation between the area of water bodies and that of different degrees of FVC. Additionally, annual frequencies of various water levels were constructed to explore their association with GPP, NPP, and FVC.The results showed that water level fluctuations significantly influence the spatial and temporal patterns of wetland vegetation cover and carbon sinks, with a significant correlation (P<0.05) between water levels and vegetation distribution. Following extensive restoration efforts, the carbon sink capacity of the Hongze Lake wetland has increased. However, it is essential to consider the carbon sink capacity in areas with low vegetation cover, for the lakeshore zone with a higher inundation frequency and low vegetation cover had a lower carbon sink capacity. These findings provide a scientific basis for the establishment of carbon sink enhancement initiatives, restoration programs, and policies to improve the ecological value of wetland ecosystem conservation areas.

Mapping Urban Transformation: The Random Forest Algorithm to Monitor Land Use and Land Cover Change in Bandar Lampung City

Bandar Lampung City has substantially altered its land cover due to rapid urbanization in the past decade. Landsat 8 OLI is suitable for conducting land cover change research and offers current and precise data on the present land cover. This research aimed to monitor and analyze the changes in seven categories of land use and land cover (LULC): forest, agricultural land, rice field, settlement, water body, bare land and industrial area. The land use and land cover (LULC) in Bandar Lampung City were analyzed using Landsat 8 OLI satellite images from 2013 to 2023. The Random Forest Algorithm was employed for this analysis. The LULC model assessment was carried out with a confusion matrix, resulting in almost perfect agreement for the 2013 and 2023 LULC models. The LULC classes showed an area growth in settlement of 5,526.25 ha (29.12%) and agricultural land of 1,071.63 ha (5.30%) but opposite with forest class that experienced significant area loss that reached 2,012.35 ha (-26.02%) and waterbody and industrial area 285.64 (-6.15%) and 167.67 ha (-4.04%), respectively. The findings reveal significant shifts in forest and agricultural land, highlighting the region’s rapid urbanization and deforestation patterns. These changes have practical implications for environmental management and urban planning, suggesting the need for sustainable LULC policies to prevent the impacts of rapid LULC transformations on ecosystem services and local communities. Keywords: Bandar Lampung, K-nearest neighbors, land use and land cover change, QGIS 3.20, random forest algorithm

Investigating the influence of land cover on land surface temperature

The increasingly serious urban heat island (UHI) effect is unfavorable to urban development. This study utilized land cover data and land surface temperature (LST) data of China in 2020 by using correlation analysis and spatial regression models to analyze the relationships between LST and two influencing factors (land cover and digital elevation model (DEM)). The results showed the following: (1) The correlation between LST and forest was highest in the Northeast China Plain (NCP), Huang-Huai-Hai Plain (HHP), Qinghai Tibet Plateau (QTP), and Loess Plateau (LP). DEM mean displayed its highest correlation in the Northern arid and semiarid region (NAR), Sichuan Basin and surrounding regions (SCR), Yunnan-Guizhou Plateau (YGP), and Middle-lower Yangtze Plain (MYP). Southern China (SC) had the highest correlation between LST and construction land. (2) There was spatial heterogeneity between land cover and LST. Unused land in LP had larger impact on LST. For every 1 % increase in the proportion of unused land area, the LST increased by 0.250 °C. LST in some central and western regions of China (the NAR, the LP, the SCR, and the YGP) was mainly affected by local land cover; LST in eastern coastal regions (the HHP, MYP, NCP, SC) and QTP was not only affected by local land cover, but also by LST or land cover of neighboring regions. The warming effect of construction land on LST was more significant, with LST increasing by 0.079 °C to 0.338 °C for every 1 % increase in the proportion of construction land area. Coordination of land use planning and synergistic remediation in different regions and rational planning of construction land are essential to mitigate the UHI effect. (3) Water bodies in the NCP, NAR, and MYP had the greatest cooling impact on LST, with LST decreasing by 0.277 °C, 0.246 °C, and 0.079 °C, respectively, for every 1 % increase in the proportion of water bodies area. Forest in the QTP, LP, SC, and YGP had the greatest cooling impact on LST, and for every 1 % increase in the proportion of forest area, LST decreased by 0.144 °C, 0.089 °C, 0.086 °C, and 0.038 °C, respectively. Actively planting trees and increasing the area of forests and water bodies are of positive significance in alleviating the UHI effect and improving the ecological environment.

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.

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.

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.

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.