An Assessment of the impact of urban forests on air pollution in Ahmedabad, India

Spatiotemporal monitoring of subtropical urban forests in mitigating air pollution: Policy implications for nature-based solutions

<p><strong>Study Objective and Design:</strong> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p> <p><br></p> <p><strong>Place and Length of Study:</strong> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p> <p><br></p> <p><strong>Methodology:</strong> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p> <p><br></p> <p><strong>Results:</strong> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p> <p><br></p> <p><strong>Conclusion:</strong> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

Study objective and design A change vector analysis (CVA) was used to determine land cover (LC) changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed LC change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe’s main roads and highways and evaluated typical urban tree species’ pH, RWC, total chlorophyll, ascorbic acid, and biomass. Place and length of study The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia’s Copperbelt Province. The investigation took place during 2018 and 2019. Methodology The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the LC were then determined using CVA, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The anticipated performance index (API), which measures the suitability of tree species for improving air quality, and the air pollution tolerance index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify the carbon sequestration contribution of the current urban forest. Results The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area’s LC. While the central business district still exhibits a persistent presence as a result of the town’s age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the current investigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species. Conclusion Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe’s urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.

<p><strong>Study Objective and Design:</strong> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p> <p><br></p> <p><strong>Place and Length of Study:</strong> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p> <p><br></p> <p><strong>Methodology:</strong> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p> <p><br></p> <p><strong>Results:</strong> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p> <p><br></p> <p><strong>Conclusion:</strong> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

Economic growth and development in urban area tend to reduce green open space that has impact on the disruption of ecosystem balance, such as temperature increase, air and waterpollution, soil surface decrease and flood risk. Efforts to eliminate those negative impact can be conducted by the development of urban forest by using potential tree species. This study was aimed to investigate, how far the PP No.63/2002 on urban forest has been accommodated by local gaverment. Location for this study was the City of Bandung, that has issued local regulation (Perda) No.25/2009 on urban forest that identifies nine urban forests in Bandung namely. Taman Tegalega, Taman Pramuka, Taman Lantas, Taman Cilaki, Taman Maluku, TPA Pasir Impun, Kebun Binatang Tamansari, and PT Pindad urban Forest. Census method was applied in this study in order to identify urban forest coverage, tree structure,tree population,tree dimension (diameter,total height, branch-free height, canopy height and width) and tree identification (genus, species, and family). This study indicatedthatall urban forests, except PT Pindad urban Forest, were utilized as sport and recreation facilites. PT Pindad urban forest was restricted as it is located inside the army industry. The highest tree diversity was at the Kebun Binatang Tamansari while the lowest was at TPA Pasir Impun. Largest tree population was found at PT Pindad forest, while the lowest one was found at TPA Pasir Impun. Almost all of tree population composing urban forests in Bandung wereexotic species. Results of this study were used to program tree species suitability matrix based on tree description (characteristics and functions) of all suitable tree species for urban forest. This potential tree matrix is, there fore recommended be used by stakeholders as a reference to determine particular tree species for urban forest development. However, selection of tree species should consider the balance with endemic, rare and endanger species.

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

<p dir="ltr"><b>Study Objective and Design:</b> A change vector analysis (CVA) was used to determine land cover changes and identify tree species that are best for urban greening based on carbon sequestration and air pollution. The study assessed land cover change in Kitwe, Zambia, from 1990 to 2015. This study identified the most planted urban tree species along Kitwe's main roads and highways and evaluated typical urban tree species' pH, RWC, total chlorophyll, ascorbic acid, and biomass.</p><p dir="ltr"><b>Place and Length of Study:</b> The urban trees in Kitwe, Zambia, make up the study population. The city of Kitwe is a thriving centre for mining and commercial activities and is situated in Zambia's Copperbelt Province. The investigation took place between 2018 and 2019.</p><p dir="ltr"><b>Methodology:</b> The NDVI and BSI indices were created using spectral indices created from Landsat images of Kitwe taken in 1990 and 2015, respectively. The size and direction of the land cover were then determined using change vector analysis, and a district database of land cover changes was constructed using GIS. Urban trees from the built-up area were utilised to create an inventory of common urban tree species based on the land cover classification. The Anticipated Performance Index (API), which measures the suitability of tree species for improving air quality, and the Air Pollution Tolerance Index (APTI), which measures the suitability of tree species for urban greening, are two of the three assessment methods that were employed. In addition, above-ground biomass (AGB) was employed to quantify thecarbon sequestration contribution of the current urban forest.</p><p dir="ltr"><b>Results:</b> The study discovered that between 1990 and 2015, mining activity and urban growth in Kitwe both contributed to changes in the area's land cover. While the central business district still exhibits a persistent presence as a result of the town's age, having sprung up before the 1990s with more expansions in the new areas, areas being monitored showed low and medium change intensity, mostly in the northeast of the district. In the currentinvestigation, there was a significant difference in the relative abundance of species (p = 0.05). In the study site, Mangifera indica (RA = 12.3%) and Delonix regia (RA = 15.9%) were the two most prevalent species. According to the study, eleven species were found, and each has accumulated carbon in a unique way throughout time depending on its allometry and age. These distinctions in physiological response (tolerance) to air pollution are noteworthy. Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia were all identified as suitable tree species.</p><p dir="ltr"><b>Conclusion:</b> Over the past 25 years, more than 50% of the land cover has changed, with the majority of that change occurring in regions that are now classified as built-up areas. The majority of Kitwe's urban forests are found in the populated areas and are made up of a variety of ornamental trees that are frequently cultivated for their aesthetic value, attractiveness, and shade. According to the research, this mixture also includes opportunistic urban trees (invasive species) and fruit-bearing trees intermingled with native species. Overall, this study suggests the following species: For urban trees suited for greening programmes aimed at improving air quality and providing shade and beauty in green areas, residences, and sidewalks that have a low air pollution environment, consider Bauhinia variegata, Toona ciliate, Gmelina arborea, Eucalyptus grandis, and Delonix regia.</p>

The purpose of this study was to investigate the effect of green roofs on air pollution in urban Toronto. The researchers looked for synergistic effects in air pollution mitigation by manipulating quantities and species of trees and shrubs at grade level and grass on roofs within the study area. The effect of these vegetation manipulations were simulated using the Urban Forest Effects (UFORE) computer model developed by the USDA Forest Service Northeastern Regional Station, Syracuse, New York. Originally UFORE was developed to help forestry managers and researchers quantify urban forest structure and risks based on standard field, meteorological and pollution data. While UFORE contains four different assessment modules A - D, Module D quantifies the effect of vegetation on air contaminants such as NO₂, SO₂, CO, PM₁₀ and ozone. UFORE also provides data about hourly air contaminant removal rates and it predicts an economic externality value in USD for total air contaminant levels. Results of the study indicate that grass on roofs (green roofs) could play a significant role in air pollution mitigation in an urban neighbourhood. By extension, a 10-20% increase in the surface area dedicated to green roofs on downtown Toronto buildings would improve air quality and quality of life for citizens of Toronto.

The purpose of this study was to investigate the effect of green roofs on air pollution in urban Toronto. The researchers looked for synergistic effects in air pollution mitigation by manipulating quantities and species of trees and shrubs at grade level and grass on roofs within the study area. The effect of these vegetation manipulations were simulated using the Urban Forest Effects (UFORE) computer model developed by the USDA Forest Service Northeastern Regional Station, Syracuse, New York. Originally UFORE was developed to help forestry managers and researchers quantify urban forest structure and risks based on standard field, meteorological and pollution data. While UFORE contains four different assessment modules A - D, Module D quantifies the effect of vegetation on air contaminants such as NO₂, SO₂, CO, PM₁₀ and ozone. UFORE also provides data about hourly air contaminant removal rates and it predicts an economic externality value in USD for total air contaminant levels. Results of the study indicate that grass on roofs (green roofs) could play a significant role in air pollution mitigation in an urban neighbourhood. By extension, a 10-20% increase in the surface area dedicated to green roofs on downtown Toronto buildings would improve air quality and quality of life for citizens of Toronto.

Diversity of trees and shrubs in agricultural systems contributes to provision of wood and non-wood products, and protects the environment, thereby, enhancing socioeconomic and ecological sustainability of the systems. This study characterizes the diversity, density and composition of trees in the agroforestry homegardens of Sidama Zone, Southern Ethiopia, and analyses physical and socioeconomic factors influencing diversity and composition of trees in the systems. A total of 144 homegardens were surveyed from 12 sites. In total, 120 species of trees and shrubs were recorded of which, 74.2 % were native to the area. The mean number of tree species per farm was 21. Density of trees varied between sites with mean values ranging from 86 to 1,082, and the overall average was 475 trees ha−1. Four different crop-based enset (Enset ventricosum (Welw.) Cheesman)-coffee homegarden types were recognized and they differed not only in the composition of major crops but also in the diversity, density and composition of trees. The composition, diversity and density of trees is influenced by physical and socioeconomic factors. The major physical factors were geographical distance between sites and differences in altitude of farms. The most important socioeconomic factors were farm size and access to roads. Tree species richness and density increased with farm size. Increased road access facilitated marketing opportunities to agricultural products including trees, and lead to a decline in the basic components of the system, enset, coffee and trees. In the road-access sites, the native trees have also been largely replaced with fast growing exotic species, mainly eucalypts. The decrease in diversity of trees and perennial components of the system, and its gradual replacement with new cash and annual food crops could jeopardize the integrity and complexity of the system, which has been responsible for its sustenance.

Quantifying the impact of urban trees on air quality in Geneva, Switzerland