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1.
Sci Total Environ ; 948: 174821, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39019283

RESUMO

China implemented continuous forestation and experienced significant greening tendency in the past several decades. While the ecological project brings benefits to regional carbon assimilation, it also affects surface ozone (O3) pollution level through perturbations in biogenic emissions and dry deposition. Here, we use a coupled chemistry-vegetation model to assess the impacts of land use and land cover change (LULCC) on summertime surface O3 in China during 2000-2019. The LULCC is found to enhance O3 by 1-2 ppbv in already-polluted areas. In contrast, moderate reductions of -0.4 to -0.8 ppbv are predicted in southern China where the largest forest cover changes locate. Such inconsistency is attributed to the background chemical regimes with positive O3 changes over VOC-limited regions but negative changes in NOx-limited regions. The net contribution of LULCC to O3 budget in China is 24.17 Kg/s, in which the positive contribution by more isoprene emissions almost triples the negative effects by the increased dry deposition. Although the LULCC-induced O3 perturbation is much lower than the effects of anthropogenic emissions, forest expansion has exacerbated regional O3 pollution in North China Plain and is expected to further enhance surface O3 with continuous forestation in the future.

2.
Heliyon ; 10(12): e32625, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975232

RESUMO

Analyzing vegetation greenness considering climate and land cover changes is crucial for Bangladesh given the historically drier North-West and South-West regions of Bangladesh have shown prominent climatic and hydrological variations. Therefore, this study assessed the spatial and temporal variation of NDVI and its relationship with climate and land cover changes from 2000 to 2022 for these regions. In this study, Moran's I and Getis Ord Gi* were employed for spatial autocorrelation and Mann-Kendall, Sen's slope test along with Innovative Trend Analysis were deployed to identify temporal trends of NDVI. RMSE, MAE and R-squared values were assessed between computed and observed PET. Correlation of NDVI with climate variables were assessed through multivariate correlation analysis and correlation mapping. Additionally, Pearson product moment correlation was applied between different types of land cover and NDVI. Spatial autocorrelation outcomes showed that NDVI values have been clustered in distinct hotspots and cold-spots over the years. Temporal trend detection results indicate that NDVI values are rising significantly all over the regions. Multivariate correlation analysis identified no climate variable to be the limiting factor for NDVI changes. Similarly, the precipitation-NDVI correlation map displayed no significant correlation. Nonetheless, temperature-NDVI correlation map illustrated varying degrees of mostly moderate and strong positive correlations with distinct negative correlation results in the Sundarbans of South-West region. Land cover pattern analysis with NDVI showed a positive correlation to forest, cropland and vegetation area increasing and negative correlation to grassland and barren area decreasing. In this regard, Rangpur division exhibited stronger correlations than Rajshahi division in North-West. The findings indicate that NDVI changes in the regions are largely dependent on land cover changes in comparison to climate trends. This can instigate further research in other hydrological regions to explore the natural and man-made factors that can affect the greenery and vegetation density in specific regions.

3.
Sci Rep ; 14(1): 10305, 2024 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705916

RESUMO

This study investigates the intricate and enduring interplay of historical events, human activities, and natural processes shaping the landscape of North European Plain in western Poland over 230 years. Topographic maps serve as reliable historical data sources to quantify changes in forest, grassland, and wetland areas, scrutinizing their fragmentation and persistence. The primary objectives are to identify the permanent areas of the landscape and propose a universal cartographic visualization method for effectively mapping these changes. Using topographic maps and historical data, this research quantifies land cover changes, especially in forest, grassland, and wetland areas. With the help of retrogressive method we process raster historical data into vector-based information. Over time, wetlands experienced a substantial reduction, particularly in 1960-1982, attributed to both land reclamation and environmental factors. Grassland areas fluctuated, influenced by wetland and drier habitat dynamics. Fragmentation in grassland areas poses biodiversity and ecosystem health concerns, whereas forested areas showed limited fluctuations, with wetland forests nearly disappearing. These findings highlight wetland ecosystems' sensitivity to human impacts and emphasize the need to balance conservation and sustainable development to preserve ecological integrity. This study advances landscape dynamics understanding, providing insights into historical, demographic, economic, and environmental transformations. It underscores the imperative for sustainable land management and conservation efforts to mitigate human impacts on ecosystems and biodiversity in the North European Plain.


Assuntos
Conservação dos Recursos Naturais , Florestas , Pradaria , Áreas Alagadas , Polônia , Conservação dos Recursos Naturais/métodos , Humanos , Biodiversidade , Ecossistema , História do Século XVIII
4.
Parasit Vectors ; 17(1): 169, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566228

RESUMO

BACKGROUND: Triatoma garciabesi and T. guasayana are considered secondary vectors of Trypanosoma cruzi and frequently invade rural houses in central Argentina. Wing and head structures determine the ability of triatomines to disperse. Environmental changes exert selective pressures on populations of both species, promoting changes in these structures that could have consequences for flight dispersal. The aim of this study was to investigate the relationship between a gradient of anthropization and phenotypic plasticity in flight-related traits. METHODS: The research was carried out in Cruz del Eje and Ischilín departments (Córdoba, Argentina) and included 423 individuals of the two species of triatomines. To measure the degree of anthropization, a thematic map was constructed using supervised classification, from which seven landscapes were selected, and nine landscape metrics were extracted and used in a hierarchical analysis. To determine the flight capacity and the invasion of dwellings at different levels of anthropization for both species, entomological indices were calculated. Digital images of the body, head and wings were used to measure linear and geometric morphometric variables related to flight dispersion. One-way ANOVA and canonical variate analysis (CVA) were used to analyze differences in size and shape between levels of anthropization. Procrustes variance of shape was calculated to analyze differences in phenotypic variation in heads and wings. RESULTS: Hierarchical analysis was used to classify the landscapes into three levels of anthropization: high, intermediate and low. The dispersal index for both species yielded similar results across the anthropization gradient. However, in less anthropized landscapes, the density index was higher for T. garciabesi. Additionally, in highly anthropized landscapes, females and males of both species exhibited reduced numbers. Regarding phenotypic changes, the size of body, head and wings of T. garciabesi captured in the most anthropized landscapes was greater than for those captured in less anthropized landscapes. No differences in body size were observed in T. guasayana collected in the different landscapes. However, males from highly anthropized landscapes had smaller heads and wings than those captured in less anthropized landscapes. Both wing and head shapes varied between less and more anthropogenic environments in both species. CONCLUSIONS: Results of the study indicate that the flight-dispersal characteristics of T. garciabesi and T. guasayana changed in response to varying degrees of anthropization.


Assuntos
Doença de Chagas , Triatoma , Trypanosoma cruzi , Humanos , Masculino , Animais , Feminino , Triatoma/fisiologia , População Rural , Argentina , Análise de Variância
5.
Heliyon ; 10(6): e27275, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38545169

RESUMO

Urbanisation is a global trend that significantly impacts sustainable urban development and the quality of urban life. Assessing urban sprawl is critical for sustainable urban planning and aligns with the key objectives of the United Nations sustainable development goals. This study employed geospatial technology and landscape metrics to comprehensively assess, map, and quantify the extent of urban sprawl in Bulawayo from 1984 to 2022. The study leveraged the Support Vector Machine (SVM) supervised machine learning algorithm coupled with landscape metrics to achieve this objective. The combined approach allowed for the classification, detection of land cover changes, analysis of urban dynamics, and quantification of the degree of urban sprawl. The results revealed a 228% increase in built-up areas between 1984 and 2022, while non-built-up areas (agricultural land, vegetation, bare land) decreased by 29.28%. The landscape metrics and change analysis indicated an encroachment of urban-like conditions into urban areas. Land use change assessment revealed that Bulawayo exhibits four district types of urban sprawl: leapfrog, strip/ribbon, low density, and infill. Urban expansion is attributed to urbanisation and evolving land use policy. Urban sprawl has numerous urban planning implications on transport management, habitat loss and deforestation, reduction and contamination of freshwater sources, and many others. This study is strategic to planners, researchers, and decision-makers/policy makers as it provides relevant, up-to-date, and accurate information for sustainable urban planning.

6.
J Environ Manage ; 352: 120009, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38184871

RESUMO

Land managers must find a compromise between rapidly changing landscapes and biodiversity conservation through ecological networks. Estimating ecological networks is a key approach to enhance or maintain functional connectivity by identifying the nodes and links of a graph, which represent habitats and their corresponding functional corridors, respectively. To understand the current state of biodiversity, it is necessary to consider dynamic landscape connectivity while relying on relevant land cover maps. Although a current land cover map is relatively easy to produce using existing data, this is challenging for past landscapes. Here we investigated the impact of changes in landscape connectivity in an urban landscape at a fine scale on the habitat availability of two bird species: the tree pipit Anthus trivialis and the short-toed treecreeper Certhia brachydactyla. These species, exhibiting different niche ecologies, have shown contrasting population trends at a medium-term scale. The occurrences of C. brachydactyla were better correlated with resistance values that maximise the use of corridors, whereas the occurrences of A. trivialis better fitted with intermediate resistance values. The statistical approach indirectly highlighted relevant information about the ecology the capacity of both species to use urban habitats. Landscape connectivity increased for both species over the 24-year study period and may have implications for local abundances, which could explain, at the national scale, the increase in populations of C. brachydactyla, but not the decrease in populations of A. trivialis. Thus, more attention must be paid on rural habitats and their associated species that are more impacted by human activities, but efforts could also be achieved in urban areas especially for highly corridor-dependent species. Studying dynamic landscape connectivity at a fine scale is essential for estimating past and future land cover changes and their associated impacts on ecological networks, to better reconcile human and biodiversity concerns in land management.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Humanos , Biodiversidade , Aves , Atividades Humanas
7.
J Environ Manage ; 353: 120192, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38286070

RESUMO

Long-term mapping of floodplain wetland dynamics is fundamental for wetland protection and restoration, but it is restricted to decadal scales using satellite observations owing to scarcity of spatial data over long-term scales. The present study concentrates on the centennial dynamics of floodplain wetland in Poyang Lake, the largest freshwater lake in China. Historical topographic maps and Landsat imagery were combined to reconstruct the centennial floodplain wetland map series. A robust random forest algorithm for the land cover classification was used to investigate the conversion of the floodplain wetland to other land cover types and quantify the magnitude of the influence of hydrological disconnection over the past century. Results show that the Poyang Lake floodplain wetland experienced a net loss of 35.7 %, from 5024.3 km2 in the 1920s-1940s to 3232.1 km2 in the 2020s, with the floodplain wetland loss occurring mostly from the 1950s to the 1970s. In addition, agricultural encroachment was identified as the predominant driver of floodplain wetland loss, with a total area of 931.0 km2 of the floodplain wetland converted into cropland. Furthermore, approximately 600 km2 of sub-lakes (larger than 1 km2) became isolated from the floodplain and thus unaffected by seasonal flood pulses, which highlights the need to account for the impact of hydrological disconnection on floodplain wetland dynamics. This study indicated the combination of historical maps and satellite observations as an effective tool to track long-term wetland changes. The resultant dataset provides an extended baseline and could shed some light on floodplain wetland conservation and restoration.


Assuntos
Lagos , Áreas Alagadas , Monitoramento Ambiental/métodos , Agricultura , China , Ecossistema
8.
Heliyon ; 9(7): e17859, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539219

RESUMO

This study investigated the dynamics of mining effects on land use land cover changes and the chemical and physical characteristics of soil and surface water in the Ahafo mining area in Ghana. Landsat imagery was used to analyze land use-land cover changes (LULC) using a supervised classification technique. Soil samples were collected within 600 m from active mining operations and at depths of up to 75 cm, as well as surface water samples from upstream and downstream of the mine. Atomic Absorption Spectrometry was used to determine the concentration of heavy metals in the soil and water samples. The results demonstrated a significant loss of forest and other vegetation covers, which decreased from 44% to 31% to 8% and 20%, respectively, with corresponding increases in the mining site, mine water, settlement/bare surface, cropland and plantation. Organic matter, organic carbon, exchangeable bases, cation exchange capacity, available phosphorus, and pH were all moderate in the soil surrounding the mine. Except for As (4.027 mg/kg) and Hg (1 mg/kg), all heavy metals found in the soil were within FAO/WHO guidelines. Total Dissolved Solids (TDS) (416.18 mg/L), Total Suspended Solids (55.08 mg/L), Turbidity (54.49 NTU), Ca (84.49 mg/L), Mg (31.97 mg/L), nitrate (10.23 mg/L), and sulphate (606.83 mg/L) in the downstream water were higher than those in the upstream and USEPA/WHO limits for drinking water except for TDS. Because of the geology of the area, there were high concentrations of iron, manganese, and aluminum in the surface water. The results show that mining induced severe land cover changes and impaired surface water and soil quality in the mine's vicinity. The findings have implications for stakeholder education, appropriate community water interventions, and company-community-regulator participatory monitoring to avoid health risk exposure and further water and soil quality and vegetation degradation.

9.
Environ Monit Assess ; 195(6): 710, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37219691

RESUMO

In semi-arid regions, interactions between biophysical and socio-economic variables are complex. Such interactions and their respective variables significantly alter land use and land cover, degrade landscape's structure, and impede the efficacy of the adopted land management interventions. This scenario is particularly prevalent in communal land tenure system or areas managed by a hybrid of traditional and state led institutions. Hence, this study sought to investigate the impacts of land use and land cover changes (LULCCs) on land degradation (LD) under communal rural districts, and the key drivers of habitat fragmentation in the Greater Sekhukhune District Municipality (GSDM), South Africa. The study used the wet and dry season multi-temporal remotely sensed image data, key-informant interviews, and workshop with tribal council to determine the major drivers of LULCC and LD. Results revealed that mines and quarries, subsistence and commercial cultivation, and thicket/dense bush LULCs declined significantly during the study period. These LULCs mostly declined in wet season, with loss in vegetation cover highly prevalent. Specifically, the highest conversions were from shrub/grassland to bare soil, thicket/dense bush to shrub/grassland, and shrub/grassland to residential, respectively. Generally, LULCC affected vegetation productivity within the study area, with increased negative NDVI values observed during the dry season. The findings from key informants and the tribal council workshop emphasized that soil erosion, abandonment of cropland, and injudicious land use (i.e. overgrazing and consequent bush encroachment) have severely degraded the land. The study also established that the degrading land can be attributed to the weakening local communal land management system, particularly the weakening tribal councils. The study recommends an urgent need for collaborative (i.e. government, tribal authorities, and land users) land management through designing relevant multi-stakeholder LD mitigation measures.


Assuntos
Clima Desértico , Monitoramento Ambiental , África do Sul , Governo , Estações do Ano
10.
Heliyon ; 9(2): e13322, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36825192

RESUMO

Land Surface Temperature (LST) affects exchange of energy between earth surface and atmosphere which is important for studying environmental changes. However, research on the relationship between LST, Land Use Land Cover (LULC), and Normalized Difference Vegetation Index (NDVI) with topographic elements in the lower Himalayan region has not been done. Therefore, the present study explored the relationship between LST and NDVI, and LULC types with topographic elements in the lower Himalayan region of Pakistan. The study area was divided into North-South, West-East, North-West to South-East and North-East to South-East directions using ArcMap 3D analysis. The current study used Landsat 8 (OLI/TIRS) data from May 2021 for LULC and LST analysis in the study area. The LST data was obtained from the thermal band of Landsat 8 (TIRS), while the LULC of the study areas was classified using the Maximum Likelihood Classification (MLC) method utilizing Landsat 8 (OLI) data. TIRS collects data for two narrow spectral bands (B10 and B11) with spectral wavelength of 10.6 µm-12.51 µm in the thermal region formerly covered by one wide spectral band (B6) on Landsat 4-7. With 12-bit data products, TIRS data is available in radiometric, geometric, and terrain-corrected file format. The effect of elevation on LST was assessed using LST and elevation data obtained from the USGS website. The LST across LULC types with sunny and shady slopes was analyzed to assess the influence of slope directions. The relationship of LST with elevation and NDVI was examined using correlation analysis. The results indicated that LST decreased from North-South and South-East, while increasing from North-East and South-West directions. The correlation coefficient between LST and elevation was negative, with an R-value of -0.51. The NDVI findings with elevation showed that NDVI increases with an increase in elevation. Zonal analysis of LST for different LULC types showed that built-up and bare soil had the highest mean LST, which was 35.76 °C and 28.08 °C, respectively, followed by agriculture, vegetation, and water bodies. The mean LST difference between sunny and shady slopes was 1.02 °C. The correlation between NDVI and LST was negative for all LULC types except the water body. This study findings can be used to ensure sustainable urban development and minimize urban heat island effects by providing effective guidelines for urban planners, policymakers, and respective authorities in the Lower Himalayan region. The current thermal remote sensing findings can be used to model energy fluxes and surface processes in the study area.

11.
J Environ Manage ; 325(Pt B): 116539, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36274338

RESUMO

Decades of intensifying human activities have caused dramatic changes in land use and land cover (LULC) in the ecologically fragile areas of the Qinghai-Tibet Plateau, which have led to significant changes in ecosystem service value (ESV). Taking the ecologically fragile Sanjiangyuan region of the Qinghai-Tibet Plateau as the research object, we focused on understanding the impact of LULC changes on the Sanjiangyuan's landscape pattern and its corresponding ESV, which was combined with a Markov-Plus model to predict LULC changes in 2030. The results showed: (1) from 2000 to 2020, the LULC of Sanjiangyuan has changed to varying degrees, respectively. In the central and southern regions where animal husbandry is the mainstay activity, the area of grass land converted to bareland had expanded; (2) from 2000 to 2010, the total regional ESV increased sharply. However, the total amount of ESV decreased from 2010 to 2020; (3) the overall ESV in the study area was observed to be trending down and is expected to decrease by approximately 4.25 billion CNY by 2030; (4) the fragmentation and complexity of regional landscape patterns will negatively affect local ecosystem stability and biodiversity. Overall, there is a strong temporal and spatial correlation between LULC and ESV. This study will provide a reference for the local government to provide targeted and sustainable land management policies, thereby promoting the improvement of the Qinghai-Tibet Plateau regional ecology value.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Tibet , Ecologia , Biodiversidade , China
12.
Heliyon ; 8(10): e10997, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36267378

RESUMO

In Ethiopia, urban areas are defined basically as places having a minimum population of 2,000. The current coverage of urban areas in the country is less than 20%, and even the majorities are small towns that account more than 85% of the urbanized areas in the country. However, urbanization in the country is increasing rapidly, at a rate of 4.63% annually. Spatially, the highest urbanization ratios occur in small towns surrounding the Ethiopia's capital city, Addis Ababa. Still, the recently urbanized areas are characterized as shanty, slum and spontaneous. On the other hand, the current rate of urbanization in the country indicates that there will be more urbanized areas in the future, which need better urban planning and management. Therefore, the purpose of this research was to identify the key drivers of the development of Ethiopia's urbanization, and to identify the management gaps that could help to predict future urbanization hotspots and trends from their early stages. Methodologically, both primary and secondary data sources were systematically applied: current urban planning and related documents, as well as land-use plans, and furthermore, high resolution historical satellite imageries of 2005, 2008 and 2018 from Google Earth Pro were analyzed. Complementary, and for validation purposes interviews and focus group discussions with experts were carried out between 2018-2021, together with on-site investigation. The results show that the drivers for the emergence of spontaneous urban development in Ethiopia relate primarily to socio-cultural components, such as in the case of worshiping places, local markets, educational and administrative centers. Physical infrastructure, such as roads played also a significant but subordinate role in the intensification of such developments. Our results demonstrate how an ineffective management of these factors has contributed to a dysfunctional urban growth. Finally, a green field level proactive planning approach is proposed and commented.

13.
Environ Monit Assess ; 194(6): 409, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35524889

RESUMO

Land use/land cover (LULC) changes due to urban growth on the regional scale affect land surface temperature (LST). The present study aims to assess the LULC changes and their impact on LST over Mardan and Charsadda districts of Khyber Pakhtunkhwa (KP), Pakistan, in the period from 1990 to 2019. Landsat satellite (TM& ETM +) datasets in the period from 1990 to 2010 and Sentinel-2 images from 2016 to 2019 were used in this study. All the datasets were pre-processed and the LULC types were classified by maximum likelihood classification algorithm. The vegetation degradation was computed from normalized difference vegetation index (NDVI), and the LST was derived based on the LULC changes. The results showed that the overall accuracy of LULC classification was 87.84%. Dramatic LULC changes were observed during the last three decades, where the vegetation degradation area was decreased from 1307.8 (59.27%) to 1147.6 km2 (52.1%) and the barren land area increased from 816.6 (37.07%) to 961.4 km2 (42.64%). Similarly, the built-up area has also increased from 57.2 (2.5%) to 104.3 km2 (4.73%) in the years 1990 and 2019, respectively. These variations in LULC types have significantly influenced the LST from 1990 to 2019; specifically, the LST of built-up area, barren land, and vegetation cover increased from 20.1 to 32.1 °C, 21.5 to 35.5 °C, and 17.1 to 28.2 °C, respectively. The regression line plotted defines that the LST has a negative correlation with NDVI and a positive correlation with normalized difference of built-up index (NDBI). In particular, the vegetation and land covers dramatically transformed to barren land and/or to urban development over the study area in the period from 1990 to2019, which has severely affected the LST and the natural resources of the study area. Therefore, our study will be very helpful for managing the rapid environmental changes and urban planning.


Assuntos
Monitoramento Ambiental , Reforma Urbana , Monitoramento Ambiental/métodos , Paquistão , Temperatura , Urbanização
14.
Environ Monit Assess ; 194(6): 453, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35610488

RESUMO

At the local and regional climate scale, one of the most studied environmental issues is urban heat island (UHI). UHI is a thermal anomaly caused by temperature differences between urban and rural settings, which adds heat to the atmosphere and makes people feel uncomfortable. This study explores the influence of new land-cover data on UHI simulations using the high-resolution Weather Research and Forecasting (WRF) model coupled with the single-layer urban canopy model (SLUCM) in the city of Harbin. A comparison was performed between the new Tsinghua University (TU) land cover dataset with the default United States Geological Survey (USGS) and Moderate Resolution Imaging Spectroradiometer (MODIS) land cover datasets. The results of this study revealed that the new TU land cover data had better representation and more realistic land cover changes than the default datasets. The diurnal, seasonal, and long-term nighttime UHIs of air and surface temperatures were higher than the daytime UHIs for both downtown Harbin and the satellite towns. We discovered that coal-burning during winter had a significant influence on UHI in Harbin. Moreover, the results from our buffer revealed a rapid increase in the UHIs of satellite towns, thus revealing the need to focus on the effects of UHI in satellite towns in the future. Therefore, the timely updating of land cover datasets in the WRF model and implementing mitigation strategies will help improve the urban climatic comfort.


Assuntos
Monitoramento Ambiental , Temperatura Alta , China , Cidades , Monitoramento Ambiental/métodos , Humanos , Imagens de Satélites
15.
Artigo em Inglês | MEDLINE | ID: mdl-34299867

RESUMO

West African coastal areas including the Beninese coastal zones have undergone an intensification of socio-economic activity in the last few decades that has been strongly driven by the effects of rapid urbanization. This has led to land-use and land cover changes that represent threats to the sustainability of various ecosystem functions. Such dynamics of land use and land cover changes pose challenges to coastal zone management. Correct assessment is vital for policymakers and planners to ensure efficient and sustainable use of the coastal ecosystem services, and it remains crucial to achieving sustainable coastal zone management. This study examines changes in land-use and land cover (LULC) and their impacts on ecosystem services value (ESV) fluctuations in the tropical coastal region of Benin, West Africa. We employed Globe Land 30 image data for the years 2010 and 2020, and the ESV fluctuations during the study period were evaluated using the benefit transfer approach (BTA) with corresponding local coefficients values and the GIS techniques. The results reveal that (1) in the current urbanizing coastal area, the LULC types have changed significantly, with obvious reductions in forest land and waterbodies and a considerable increase in artificial surfaces; (2) the total ESV decreased by 8.51% from USD 7.1557 million in 2010 to USD 6.5941 million in 2020; (3) the intensity of LULC in the coastal region has increased over the last 10 years; (4) regions with high land-use intensity have a high rate of ESV change; and (5) provisioning services are the greatest contributors of ESV (51% in 2010; 41% in 2020), followed by supporting services (37% in 2010; 35% in 2020) and regulating services (25% in 2010; 30% in 2020). Uncontrolled changes in LULC from forest land and waterbodies are the main causes of the loss in total ESV, necessitating urgent measures to improve the coastal ecosystem sustainability through effective planning and policies.


Assuntos
Ecossistema , Urbanização , Benin , China , Conservação dos Recursos Naturais , Florestas
16.
Environ Sci Pollut Res Int ; 28(31): 41675-41687, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33791965

RESUMO

The impacts of vegetation cover changes (VCCs) and land use land cover changes (LULCCs) on climate variabilities need to be addressed while maintaining healthy urban development. This study aimed to evaluate LULCCs and VCCs and their impacts on land surface temperature (LST) and rainfall in the Darbhanga district of Bihar, India. Landsat data and climate hazard group infrared precipitation with stations (CHIRPS) were used to assess LST or LULCCs and rainfall, respectively, over the study area. Results showed a decline in vegetation cover to 11.73% (26,857.43 ha) in the year 2019 from 19.12% (43,733.61 ha) in 1999. Also an increase in built-up and cropland by 4.9% (11,224.6 ha) and 4.38% (10,043.2 ha), respectively, was observed in the last 20 years. With decreasing vegetation cover in the study area, the mean LST increased while the mean annual rainfall decreased for the study period. The Mann-Kendall trend (MKT) test exhibited no significant trends for LST and rainfall with p values of 0.43 and 0.69, respectively, although Sen's slope indicated variability in LST and rainfall even though it was insignificant over the study area. The study would identify areas requiring immediate action for saving its resources and providing insight into upholding its competence. The findings would also lead to proper decision making for the concerned stakeholders, assuring sustainability in appropriate planning of land use and utilisation of resources and maintain the agroclimatic condition.


Assuntos
Monitoramento Ambiental , Tecnologia de Sensoriamento Remoto , Humanos , Índia , Temperatura , Reforma Urbana
17.
J Environ Manage ; 288: 112291, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33773212

RESUMO

A Compound Specific Stable Isotope (CSSI) sediment tracing approach is applied for the first time in a Mediterranean mountain agroforestry catchment subjected to intense land use changes in the past decades. Many Mediterranean mountain environments underwent conversion of rangelands into croplands during the previous centuries to increase agricultural production. Converted land has increased the risk of erosion and in some cases has led to loss of the entire fertile topsoil. After land abandonment the process was gradually reversed during the middle of the 20th century, allowing the recovery of natural land cover and reduction of soil erosion rates. The 13C abundance of long chain fatty acids was used as tracer to assess the contribution of soil under different vegetation covers in complex landscapes subjected to land use changes after land abandonment in a medium-sized Mediterranean catchment. A Bayesian mixing model (MixSIAR) was used for estimating the contribution of different land use types to suspended sediments. To this purpose, composite samples were collected over the four main land covers existing in the study area: cropland, Mediterranean forest, pine forest, scrubland, and two main geomorphic elements: highly disturbed areas such as exposed subsoil and channel banks. Suspended sediment traps were installed at three locations in the catchment to assess the variability of source contributions from the headwaters to the outlet of the catchment. At every sampling point three replicating traps integrated the suspended sediment per climatologic season during a one hydrological year. The fatty acids (FAs) content was significantly higher at the catchment outlet than at the headwaters. The δ13C signatures of the FAs were successful in discriminating between Mediterranean forest, scrubland, pine forest and both geomorphic elements. Overall, the model identified agricultural land as the largest contributing source for most of the sampled seasons. The inclusion of prior information with different informativeness produced variations in the model outputs and could represent an advantage as much as a disadvantage if priors are not used with caution and supported by robust evidence. The results of this study suggest that CSSI tracers are needed to correctly assess land use related sediment sources, while channel bank and subsoil contributions require geochemical tracers. The high agricultural apportionment despite its small coverage (16%) point out to the impact of human activities and the agriculture cycle on soil loss in these mountain agroforestry systems.


Assuntos
Sedimentos Geológicos , Solo , Agricultura , Teorema de Bayes , Florestas , Humanos
18.
Sci Total Environ ; 771: 145431, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736174

RESUMO

The present work reviews the main challenges regarding adaptation of urban drainage networks to climate change by comparing 32 case studies from 29 articles, published between 2003 and 2020. The aim is to: (i) identify the state-of-the-art scientific approaches of adaptation of urban drainage networks to climate change; (ii) assess whether or not these approaches incorporated monetization of the adaptation practices and the associated costs/benefits; and (iii) define a novel approach (Blueprint) for the future development and assessment of urban drainage network adaptation to climate change and other drivers. First, the motivation is provided that makes urban drainage adaptation a globally relevant issue. Second, the main impacts of climate change on precipitation, flooding and urban drainage systems are discussed. Then, current practices are described. Finally, a blueprint for an integrated urban adaptation framework to climate change and other drivers is proposed. Our research indicated that future quantity and quality of urban runoff is not widely addressed in the scientific literature. The Storm Water Management Model is the most widely used software in modeling adaptation options. Solutions such as plans of maintenance and rehabilitation, public awareness, flood forecasting and warning, mobility measures and insurance measures are not widely reflected in the literature. Uncertainties of climate projections and bias correction methods are still significant, and uncertainties of socio-economic scenarios, hydrologic and hydrodynamic models, and adaptation options are not fully addressed. Finally, environmental cost and benefits associated with the ecosystem services provided by the adaptation options are not fully addressed.

19.
Sci Total Environ ; 778: 146017, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714812

RESUMO

This study aims to evaluate the individual and synergistic controls of climatic and land cover changes on stormwater runoff regimes, and perform a comparative synthesis of the historical and future runoffs for complex coastal-urban environments. A large-scale (7117 km2) mechanistic hydrologic model was developed for Florida Southeast Coasts Basin as the study area using U.S. Environmental Protection Agency (EPA)'s Storm Water Management Model 5.1. The model was calibrated and validated with daily streamflow observations (Nash-Sutcliffe Efficiency = 0.74 to 0.92) during 2004-2013 (termed 2010s), computing the corresponding runoff volume as a historical reference. Runoffs for 2050s (2044-2053) and 2080s (2076-2085) were quantified by incorporating climatic projections from 20 General Circulation Models and land cover projections from EPA under the Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. We found a predominant climatic control on the potential runoff changes and a high vulnerability in the coastal-urban environments. The concurrent changes in climate and land cover led to synergistic (stronger than the sum of individual effects) nonlinear responses of runoff. The projected changes in climate and land cover together would increase the annual basin runoff volume by 118%, 106%, 86%, and 80% under the 2080s-RCP 4.5, 2050s-RCP 4.5, 2050s-RCP 8.5, and 2080s-RCP 8.5 scenarios, respectively. Greater increases in runoff were noted at and around the urban centers than that at the non-urban areas across the basin. The relative increases in runoff were higher during the dry season and transitional months (October-May) than the wet season (June-September). Our findings would guide stormwater management and ecosystem protection for southeast Florida and coastal built environments across the world.

20.
Environ Monit Assess ; 191(11): 694, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667631

RESUMO

This study, using remote sensing techniques and GIS, studied the land use land cover (LULC) changes of Anzali International Wetland from 1975 to 2013, and the effects of these changes on the ES (ecosystem service) values of the wetland. The benefit transfer method was used to estimate the economic value of the ecosystem goods and services. The basis for the valuations was the values provided for the ES of the world biomes. According to the results, in the period of study (1975 to 2013), the highest percentage of incremental change was attributed to urban and manmade centers (73.85 %), while the lowest was related to the wetland coverage area (0.32 %). Value changes between 1975 and 1975 for agricultural lands were positive and equal to US$ 12.85 million and for the rangelands were negative and equal to US$ - 26.84 million. These changes were positive for the coastal wetlands, equivalent to US$ 258.95 million a year. Despite the negative value changes of the rangelands, the total ES value changes in the entire wetland during the years 1975 to 2013 were evaluated to be positive (equal to US$ 244.96 million). Changes in the value of the services of pollination, biological control, genetic resources, and food production in 2013 were negative, compared to 1975. This indicates the loss of these values, which is due to the loss of rangelands in the study area. The findings of this study can inform policymakers, managers, and environmental planners about the continuation of the changing process and may lead to the formulation of policies for the sustainable exploitation of land resources, as well as future effective land use planning for achieving the goals of sustainable development in the study area. The findings can serve as a tool for raising awareness about the contribution of nature to the benefits, social welfare, and livelihood of the stakeholders.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Áreas Alagadas , Agricultura , Ecossistema
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