Significant Changes In Land Cover Research Articles

Impacts of Wildlife Artificial Water Provisioning in an African Savannah Ecosystem: A Spatiotemporal Analysis

The use of artificial water points for wildlife in African savannah ecosystems has been widely criticised for affecting the distribution of wildlife and initiating changes in the heterogeneity of natural landscapes. We examined the spatiotemporal variations in the landscape before and after the installation of an artificial water point by integrating the analysis of vegetation and soil spectral response patterns with a supervised learning random forest model between 2002 and 2022 in Chobe Enclave, Northern Botswana. Our results revealed that the study area is characterised by animal species such as Equus quagga, Aepyceros melampus, and Loxodonta africana. The findings also showed that the main vegetation species in the study area landscape include Combretum elaeagnoides, Vachellia luederitzii, and Combretum hereroense. The artificial water point induced disturbances on a drought-vulnerable landscape which affected vegetation heterogeneity by degrading the historically dominant vegetation cover types such as Colophospermum mopane, Dichrostachys cinerea, and Cynodon dactylon. The immediate years following the artificial water point installation demonstrated the highest spectral response patterns by vegetation and soil features attributed to intense landscape disturbances due to abrupt high-density aggregation of wildlife around the water point. Landscapes were strongly homogenised in later years (2022), as shown by overly overlapping spectral patterns owing to an increase in dead plant-based material and senescent foliage due to vegetation toppling and trampling. The landscape disturbances disproportionately affected mopane-dominated woodlands compared to other vegetation species as indicated by statistically significant land cover change obtained from a random forest classification. The woodlands declined significantly (p < 0.05) within 0–0.5 km, 0.5–1 km, 1–5 km, and 5–10 km distances after the installation of the water point. The results of this study indicate that continuous nonstrategic and uninformed use of artificial water points for wildlife will trigger ecological alterations in savannah ecosystems.

Selected Driver Variables for the Simulation of Land-Use and Land-Cover Change for the Republic of Djibouti: A Study from Semi-Arid Region

Abstract. This study aims to integrate driver variables with a land use change model (LCM) to explore their impact on the natural environment within the context of land-use changes in the Republic of Djibouti, considering possible Business-as-usual scenarios. Secondary data from 1990 and 2012 on land use land cover (LULC) were analyzed, with a 2022 map generated by adopting the same method of secondary data used (random forest classification in Google Earth Engine (GEE)) for validation. Eight key driver variables were utilized to model plausible future land cover (2035) for Djibouti. Statistical outputs and change maps from the LCM were compared to gauge historical change estimates and simulated scenarios. Analysis from 1990 to 2022 highlights significant land use and cover changes spurred by urbanization, environmental factors, and economic development. Barren land and bushland dominated, while built-up areas and water bodies expanded notably. Urbanization, agriculture, and climate change contributed to vegetation degradation, with declines in mangroves and increases in built-up areas. Water bodies also expanded during this period. Projections from the 2035 LULC map anticipate further urban expansion, underscoring the need for sustainable land management practices. In conclusion, comprehensive land-use planning, interdisciplinary approaches, and stakeholder engagement are deemed critical for addressing Djibouti's socio-economic and environmental challenges and steering towards a sustainable future. These simulated results offer valuable insights for regional governments to frame strategic policies and assess management actions for resource utilization amidst urbanization and population growth trends.

Land Cover Dynamics in the Northwestern Virunga Landscape: An Analysis of the Past Two Decades in a Dynamic Economic and Security Context

The Beni region in the eastern Democratic Republic of Congo is grappling with socioeconomic development and security challenges that have affected its natural ecosystems, especially those located in the northern Virunga National Park. This study aims to document the anthropization of the northwestern Virunga landscape from 1995 to 2021 in the context of insecurity. Using a cartographic approach and ecological-landscape-analysis tools, this study delves into the overall landscape changes through a comparative analysis of protected and unprotected areas. These investigations focus on landscape composition, transitions between land-cover classes, and the spatial transformation process. The northwestern Virunga landscape is undergoing significant land cover changes due to the influence of insecurity on socioeconomic activities, primarily agriculture. Agricultural land encompasses a larger area than other land-cover types. However, its expansion has decelerated since the 2000s. The loss of forested area is discontinuous. During relatively stable periods (1995–2005), forests exhibited a reduction of up to 2.90% in area, while in the period of the return of Iturian refugees to their province, followed by terrorist insecurity in Beni (2005–2021), the forested area increased by 2.07%. Savannah areas, which are mainly located in the graben rift valley and near Butembo, have been more heavily affected by human activity than forests. Ultimately, the apparent stability of the landscape can be attributed to its protected areas, especially Virunga National Park.

Quantifying the impacts of land cover change on the hydrologic response to Hurricane Ida in the Lower Mississippi River Basin

Abstract The Lower Mississippi River Basin (LMRB) has experienced significant changes in land cover and is one of the most vulnerable regions to hurricanes in the United States. Here we study the impacts of land cover change on the hydrologic response to Hurricane Ida in LMRB. By using an integrated surface-subsurface hydrologic model, ELM-ParFlow, we simulate the effects of land cover change on the flood volume and peak timing induced by rainfall from Hurricane Ida. The results show that land cover changes from 1850 to 2015, which resulted in a smoother surface and less vegetation, exacerbated both flood peak time and volume induced by Hurricane Ida. The effects of land cover changes can be decomposed into two mechanisms: a smoother surface routes more water faster to a watershed outlet, and less vegetation allows more water to contribute to surface runoff. By comparing scenarios in which the two mechanisms were isolated, we found that changes in soil moisture due to vegetation cover change have more dominant effects on floods in the southern part and changes in Manning’s coefficient have the largest effect on floods in the northern part of the LMRB. The study provides important insights into the complex relationship between land use, land cover, and hydrologic processes in coastal regions.

The Relationship between Climate, Agriculture and Land Cover in Matopiba, Brazil (1985–2020)

Climate change has been at the forefront of discussions in the scientific, economic, political, and public spheres. This study aims to analyze the impacts of climate change in the Matopiba region, assessing its relationship with land cover and land use, soybean crop production and yield, and ocean–atmosphere anomalies from 1985 to 2020. The analysis was conducted in four parts: (1) trends in annual and intra-annual climate changes, (2) the spatiotemporal dynamics of land cover and use, (3) the spatiotemporal dynamics of soybean production and yield, and (4) the relationship between climate change, agricultural practices, land cover and use, and ocean–atmosphere anomalies. Statistical analyses, including Mann–Kendall trend tests and Pearson correlation, were applied to understand these relationships comprehensively. The results indicate significant land cover and use changes over 35 years in Matopiba, with municipalities showing increasing soybean production and yield trends. There is a rising trend in annual and intra-annual maximum temperatures, alongside a decreasing trend in annual precipitation in the region. Intra-annual climate trends provide more specific insights for agricultural calendar planning. No correlation was found between the climate change trends and soybean production and yield in the evaluated data attributed to genetic and technological improvements in the region. The North Atlantic Ocean shows a positive correlation with soybean agricultural variables. Evidence suggests soybean production and yield growth under climate change scenarios. This study highlights soybeans’ adaptation and climate resilience in the Matopiba region, providing valuable insights for regional agricultural development and contributing to further research in environmental, water-related, social, and economic areas of global interest.

Watershed hydrological responses to land use land cover changes at Bilata watershed, Rift Valley Basin, southern Ethiopia

Abstract Most anthropogenic activities have a profound effect on land cover that affects the water cycle and, ultimately, the availability of water in the watershed. The idea of this study was to evaluate the hydrological response to land use and land cover change in the Bilata watershed. To achieve this objective, supervised land use land cover classification was applied for the years 2000, 2010, and 2020 using ERDAS IMAGINE 2015. The watershed underwent significant land use and land cover changes from 2000 to 2020. There was an abrupt expansion of agricultural land and a reduction of forest. The SWAT model was applied to evaluate the impact of land use and land cover change on hydrological processes. The calibration and validation of the SWAT model showed that the model has performed well in simulating the hydrology of the watershed with a coefficient of determination, Nash–Sutcliffe efficiency, and per cent of bias greater than 0.6 for both calibration and validation. Due to intensive agricultural expansion and settlement, the surface runoff increased from 172 to 259.5 and 265.0 mm in 2000, 2010, and 2020, respectively. The average streamflow increased from 132 to 134 and 150 m3/s between 2000, 2010, and 2020.

Effects of land use and land cover change under shared socioeconomic pathways on future climate in the Yellow River basin, China

The Yellow River basin of China has experienced significant land use and land cover change (LUCC) due to excessive exploitation of nature resources, ecological degradation, and rapid urbanization, which plays an important role in the regional climate. It is crucial to explore the climate patterns of the basin under different future development scenarios to mitigate climate issues and achieve “carbon peaking and carbon neutrality goals”. Here we utilized land use and land cover (LULC) data and projections of future climate under two shared socioeconomic path – representative concentration path (SSP245 and SSP585) scenarios. Using the Weather Research and Forecasting (WRF) model, we simulated four future spatial variation patterns of temperature and precipitation in the basin. Results indicated that under the SSP245 and SSP585 scenarios, the temperature is projected to increase by 0.18 °C and 0.46 °C, respectively, while precipitation is expected to rise by 32.21 mm and 134.24 mm, respectively. The impact of LUCC was found to be relatively minor and mainly concentrated in the middle reaches of the basin. It resulted in a slight increase in temperature in both scenarios and an increase in precipitation in SSP245, but a decrease in precipitation in SSP585. Changes in farmland and urban area exhibited a certain warming effect in both scenarios, with urban areas having a greater influence, leading to a temperature increase by 0.25 °C and 0.28 °C, respectively. Forest, grassland, and bare areas had a lesser impact on temperature and showed different trends under two scenarios. Regarding precipitation, forests and urban areas had a greater influence in both SSP245 and SSP585 scenarios. This study identified the significant role of LUCC under different development scenarios in shaping future temperature and precipitation changes, providing valuable insights for effectively addressing climate issues in the Yellow River basin. It also highlights the need for clear policy recommendations and identifies institutions or agencies responsible for implementing such recommendations.

Analysis of land cover change in Sagara Anakan Cilacap, Central Java using principal component analysis (PCA)

Land cover in area Mangrove, an ecosystem with high productivity, is an ecological link that is very important for life in the waters. This study aims to identify land cover vegetation, water bodies, and soil using Principal Component Analysis (PCA) method with imagery using Landsat imagery for 1997 and 2021 carried out by processing Landsat 7 and Landsat 8 OLI images consisting of pre-processing processes and image classification. The results showed that in the mangrove area in Sagara Anakan, there was a significant change in land cover; for the lagoon area, the land cover was overgrown with mangrove forests, but areas far from the lagoon had changed to settlements or sparse vegetation.

Application of Satellite Images and Artificial Intelligence to Monitor Land Cover Changes in Hanoi Area During 2013-2023 Period

Artificial intelligence (AI) and remote sensing technology have now increasingly improved their efficiency and reliability in monitoring the changes in land cover. With the amendment of the Vietnamese Law on Land in 2013 and the administrative boundary expansion of Hanoi, Hanoi experiences significant changes in land use and land cover for the last ten years. To monitor the actual land use changes in the area, this study used the Random Forest (RF) machine learning algorithm to classify the basic land covers, monitor, and analyze the spatial variation of land use and land cover in the 2013 to 2023 period. The study findings indicate a relatively high rate of expansion of construction zone area and a decrease in land cover related to water bodies and vegetated area. Water bodies decrease by an average of 0.8% annually, whereas the construction zone area increased by 7% of the total area.

Land-based investment implications on land use land cover change and livelihood of the local community in Northern Amhara Region, Ethiopia

A surge in land-based investment has been taking place in developing countries, including Ethiopia, with the aim to foster economic growth, enhance food security, and reduce poverty. This study sought to investigate the impact of such investments in the western Armachiho district of the Amhara Regional State, Ethiopia, using remote sensing data from 1995, 2010, and 2020 supplemented by socioeconomic surveys and field observation to validate the spatial data. The results revealed significant land use and land cover changes in the district over the past twenty-five years. Forest cover decreased from 60.92% in 1995 to 27.6% in 2010, while water bodies, including rivers, streams, and ponds, declined from 3.04% to 1.4% during the same period. Conversely, built-up areas, bush land, farmland, and bare land exhibited an increasing trend. The observed changes during the initial study period can be attributed to the expansion of land-based investments and illegal farmland encroachment in the area under investigation. The results further indicated that the expansion of such investments during this period had adverse effects on the local community, resulting in the loss of access to farmland, grazing land, and forest products that served as sources of income. The results also demonstrated that the delineation of agricultural investment land, the closure of unproductive land, and the issuance of land-holding certificates have prevented illegal encroachment that contributed to the improvements in forestland cover between 2010 and 2020. Hence, when granting significant amounts of land for land-based investment, it is crucial to consider not only the short-term economic benefits but also the well-being of local communities and the principles of environmental sustainability.

Enhancing Understanding of Hydrologic Processes in the Shafe Watershed, Ethiopia

Research on the combined impact of watershed attributes on streamflow is crucial in water resources planning and management, particularly due to the strong link between landscape modification and watershed attributes. However, identifying critical watershed attributes remains a challenge. This study focuses on investigating the impact of watershed attributes on streamflow in the Hare catchment of Ethiopia’s rift valley lakes basin. The Soil and Water Assessment Tool (SWAT) rainfall–runoff model was used, calibrated, and validated against observed discharge data to identify remedial measures for streamflow generation. The model’s performance was evaluated using criteria such as R2, NSE, PBIAS, and RSR, which yielded satisfactory values. The study found significant changes in land cover, with forest and shrub land declining and agricultural land expanding. Comparing mean annual streamflow between 1998, 2009, and 2021, streamflow at 2021 land use and land cover increased by 13.03% compared to 2009, which had already increased by 16.05% compared to 1998. The study also examined the impact of climate variations by manipulating meteorological data length and average slope. Overall, this study provides valuable insights into the relationship between watershed attributes and streamflow, emphasizing the importance of considering land cover changes and climate variations for effective water resource management in the Hare catchment.

Causes and consequences of forest cover transformation on human-wildlife interaction in the Teknaf Wildlife Sanctuary, Bangladesh

Protected Areas (PAs) in Bangladesh have been pivotal for conserving wildlife. The country plans to increase the number of PAs by implementing new forest-governing policies with the involvement of local communities. Their efficacy in wildlife conservation and forest preservation is being questioned due to significant land cover changes within PA boundaries. It is essential to understand the current role of existing PAs in forest cover transformation and their impact on wildlife conservation before expanding the PAs and implementing new policies. This study aims to explore the land cover transformation within Teknaf Wildlife Sanctuary (TWS) and describe the role of the local community and its impact on wildlife. Utilizing Landsat satellite images from 1989 to 2015, this study discovered a 46 % deforestation rate within TWS, surpassing its surrounding areas. Since 1989, 75 % of primary forests have been eradicated, leaving a mere 650 hectares intact. This transformation is shifting forested areas towards the PA boundaries, potentially threatening conservation efforts by making wildlife more vulnerable. Socioeconomic surveys of 5769 households revealed that bigger landowners within the local communities played a significant role in this deforestation. Such community-driven forest alterations increased wildlife vulnerability by intensifying their interaction with forest surrounding communities. This study presents an interesting case of the process of forest transformation within PAs with the intersection of human-wildlife conflict and deforestation. For effective wildlife conservation, strategies need to address and rectify these forest cover transformations and focus on the wildlife habitats, ensuring conservation and coexistence for forests, humans and wildlife.

Influence of human-induced land use change on hydrological processes in semi-humid and semi-arid region: A case in the Fenhe River Basin

Study Region: The Fenhe River Basin (FRB) is an important tributary of the Yellow River Basin and locate in a semi-arid and semi-humid region in northwest China. Over the past four decades, significant anthropogenic activities have resulted in significant land use and land cover change (LUCC) that have markedly impacted hydrological processes in FRB.Study Focus: To analyze land use changes under multiple historical land use scenarios from LU1980 to LU2015, and to establish the Water and Energy transfer Processes in Large basins (WEP-L) model to quantify the influences of LUCC on hydrological processes, particularly on baseflow.New hydrological insights for the region: LUCC from LU1980 to LU2015 resulted in a 14.5 % increase in water yield (WY) and a 2.7 % and 1.4 % decrease in baseflow (BF) and evapotranspiration, respectively. Urbanization led to a significant increase in WY and a reduction in BF, exhibiting strong spatial gradients between urban centers and their peripheries. Increases in forestland decreased WY, while ET showed no significant change due to large absolute values and moisture limitations. Furthermore, the response of BF to forest cover exhibits spatial variation. A negative correlation between BF and forest cover was evident in upstream, whereas no significant correlation was observed in downstream. The findings of this study offer valuable insights for land use planning and sustainable watershed management in semi-arid semi-humid region.

Two decades of winter wheat expansion and intensification in Russia

Since 2000, Russia experienced large-scale increases (149%) in wheat production and starting in 2018 accounted for almost 25% of all global wheat exports. This growth indicates significant land cover and land use change (LCLUC) and is driven primarily by winter wheat growth adding 9 million hectares of cropland area, a 117% increase, since 2000 according to data reported by the Russian government. However, the spatial distribution of this growth in addition to projections for continued growth are not characterized. Therefore, the aim of this study is to comprehensively examine the growth of the Russian wheat industry and quantify LCLUC within the lens of cropland expansion and intensification. Understanding this growth is critical due to Russia being a top global producer and exporter of wheat where changes in its domestic industry directly affect world wheat market stability and food security as well as environmental consequences of such growth. We took advantage of long-term satellite data records acquired by Moderate Resolution Imaging Spectroradiometer (MODIS) to map yearly winter crop in southwestern Russia at a 250-m spatial resolution. These winter cropland maps were then analyzed based on their corresponding changes in expansion and intensification between 2001 and 2020. A rigorous sampling campaign was then conducted to provide estimates of areas and corresponding uncertainties for each land cover change type within selected time period. Here, we show that 40% of southwestern Russia experienced changes in land cover and land use including a 29% growth in winter wheat cropland. Of this growth, 66% is attributed to winter wheat cropland expansion (planting in new areas) and 34% to intensification (increased planting rate). The observed growth in winter cropland was latitudinally dichotomous where northernmost regions experienced areal expansion and southernmost regions intensification. Lastly, based on ratios of winter cropland use in comparison with total available agricultural land in the study area, we conclude that there remains significant capacity for winter crop intensification and provide probable trajectories of continued growth.

Dynamics of land cover change, regional development, and its local dependence driving factors in Bojonegoro Regency

Bojonegoro is a regency in East Java province with a population of 1,322,474 (BPS, 2022) and high population density. Population growth is strong, and demand for land is increasing. Increased human activity leads to land conversion, which could impact regional development. The objectives of this study are to: 1) Analyze the dynamics of land cover change, 2) Compare the SDI (Sub-district Development Index) scores of 2008 and 2020 in Bojonegoro Regency, and 3) Analyze the factors affecting the level of Regional development in Bojonegoro Regency. The methods used are overlay (GIS analysis), scale plot analysis, and geographically weighted regression (GWR) analysis. The most significant land cover change occurred in forest cover, with the area decreasing from 99,815 hectares (2000) to 84,845 hectares (2020), while the built-up area increased from 12,665 hectares (2000) to 22,901 hectares ( 2020). Bojonegoro sub-district has the highest SDI of 44,043 (2008) and 44,917 (2020) because it has the largest population and become a capital district and central business district (CBD). Based on the results of the GWR analysis, the highest local R2 is located in the eastern part of the Regency. In contrast, the lowest local R2 is located in the western administrative district of Bojonegoro Regency. The results show that the driving forces influencing regional development in Bojonegoro Regency vary spatially.

Detection of Land Use/Land Cover Change and Land Surface Temperature in the Eastern Part of Batna City (North East Algeria) Using Remote Sensing Data and GIS


 
 
 The present paper aims to evaluate the accuracy of classifying Land Use /Land Cover (LULC) types and assesses the trends of their changes in the Eastern Part of Batna City (Northernf Algeria) using remote sensing and GIS. The accuracy of image Land Satellite (Land Sat ) was evaluated using the supervised classification technique, it’s applied in multi spectral and multi temporal satellite data acquired in 2000,2010,2022 and assessed with GOOGLE EARTH PRO and IMAGERY Land Use and topographical map. The second part focused on extraction of LST in three phases and explored the relationship between two land cover indices (NDVI, NDBI) and LST.LU/LC detected, quantified, and stati- cally analyzed, the result indicate that from 2000-2022 the built-up areas increased by 0.34% (6.638km2), the forest area increased by 1.8% (35.144km2), agricultural land cover increased by 1.12% (21.867km2), while bare land decreased by 2.17% (42.368km2). The conversions of areas from bare land to urban land represent the most significant Land Cover changes. The accuracy assessment and correlation coefficient R2 analysis in this study affirms the previous research findings. Even a single land use unit like built-up area, bare land and vegetation also create differences in LST (R2 of NDBI vs. LST ranges from 0.64 to 0.79; NDVI vs. LST ranges from -0.73 to -0.82). With the change of the LU/LC style, its imprint is reflected on the LST. Therefore, immediate reflection on new urbanism must be adopted, initiated and implemented to stop the warming that contributes to climate change in the study area.
 
 

The Impact of Environmental, Social, And Economic Factors Due to Anak Krakatau Volcano Tsunami Using Remote Sensing Technology

Tsunamis often occur in the territory of Indonesia because it is widely traversed by encounters between earth plates under the sea. Thus, if an earthquake occurs, it has the potential to generate a tsunami. The Indonesian region is also located in the ring of the fire area, and is the country with the highest number of active volcanoes with more than 127 events, that can encourage volcanic earthquakes. In addition, when volcanoes erupt offshore, the potential for a tsunami will be even greater because the expulsion of material can generate landslides toward the sea, causing a tsunami. The tsunami that happened in the eruption of Anak Krakatau on December 22, 2018, in the Sunda Strait, resulted in a tsunami in the Lampung and Banten areas. This study tries to compare environmental, social, and economic factors before and after the tsunami in the coastal areas of Lampung and Banten. The integration of remote sensing data will be carried out to determine environmental, social, and economic factors such as Land Cover, NDWI, NDVI, Night Light, and NO2 data. Random Forest Machine Learning will also be involved in shaping land cover models. Random Forest is often used because it has high accuracy. The results show a significant change in land cover in coastal areas and the impact of environmental, social, and economic factors. This study is expected to support the mitigation process in the event of a tsunami in the future. In addition, it is expected to be used by policymakers in planning development after the tsunami disaster.

Community-based forest monitoring for REDD+ MRV in the Ankasa Conservation Area, Ghana

A community-based monitoring (CBM) approach creates a working relationship between scientists, resource managers and local communities to address natural resource problems. This study analyses CBM data from Ankasa Conservation Area (ACA), Ghana, and assesses how such a CBM model fits into the national Measurement, Reporting and Verification (MRV) system for REDD+. Satellite imagery was used to generate land cover change maps for the different land use categories in ACA. A checklist of deforestation and forest degradation-related activities was designed with inputs from study communities. Nominated community members were trained to collect the data. The land use categories identified in the study area include closed forest, open forest, farmland, bare area, and grassland. The remote sensing data revealed significant land use and land cover changes in the periphery of ACA between 1990 and 2014. Closed forest and open forest areas recorded 28.6% and 35.0% reductions respectively. Data from the CBM showed that cash crop farms and plantations (rubber and coconut) account for the sharp increase (479.9%) in farmlands. The predominant sighting of rodents by community monitors reinforced the deforestation and forest degradation findings in the ACA periphery. A participatory MRV system is essential for the success of REDD+ interventions. With little training, local people can collect forest condition data that are of interest to REDD+ implementation and international policies related to climate change.

Significant land cover change in China during 2001–2019: Implications for direct and indirect effects on surface ozone concentration

China has become one of the most prominent areas of global land cover change during the past few decades. These changes can directly influence meteorological parameters thus further regulating tropospheric ozone (O3) formation. Moreover, changes in biogenic emissions due to land cover variation can also have an indirect effect on O3 concentration. This study applied the Community Multiscale Air Quality model to comprehensively evaluate the impacts of significant land cover change on O3 levels in China during summertime between 2001 and 2019. The results showed that the daily maximum 8–h average O3 concentration (MDA8 O3) increased by 3.6–8.9 μg/m3, 2.8–8.0 μg/m3, 3.8–9.6 μg/m3, -1.5–6.2 μg/m3, and -0.6–2.5 μg/m3 in Beijing–Tianjin–Hebei region, Yangtze River Delta, Pearl River Delta, Sichuan Basin, and Fenwei Plain, respectively, in response to land cover variation. The research identified that the direct effect was the primary factor in raising O3 levels which mainly altered O3 concentration by changing vertical import and dry deposition velocity. Moreover, land cover variation tended to decrease biogenic nitric oxide emission and increase biogenic volatile organic compounds emission on the whole, and cause an obvious increase of MDA8 O3 by 1.8–4.9 μg/m3 in Pearl River Delta due to the indirect effect. This study offered valuable insights into the impacts of land cover change on O3 levels, highlighting the need for policymakers to consider land cover variation on air pollutants concentration for devising comprehensive multi-pollutant control strategies.

Mangrove cover change (2005–2019) in the Northern of Medan City, North Sumatra, Indonesia

Medan City is the third-largest city in Indonesia and serves as the capital of North Sumatra Province. The city has several sub-districts with mangrove forests, with the largest area located in Medan Belawan Sub-district, followed by Medan Labuhan and Medan Marelan Sub-districts. The mangrove forests are situated in the downstream part of the Deli Watershed or the northern part of Medan City. Over the past fourteen years, there has been a significant change in the mangrove land cover, particularly in Medan Labuhan Sub-district. To address this issue, an integrated remote sensing, Geographic Information Systems (GIS), and Analytical Process Hierarchy (AHP) approach was used to map and analyze changes in mangrove cover and determine priority factors to prevent further changes. The study found that the mangrove forest area in Medan Labuhan Sub-district has decreased by 111.25 ha over the years, and the economy was identified as the top priority criterion for preventing changes in mangrove cover. The study recommends efforts from all parties to minimize changes in mangrove forest cover to maintain the function of the mangrove ecosystem, and this approach can help decision-makers and stakeholders make informed decisions about mangrove ecosystem management and conservation in Medan City.