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1.
J Environ Manage ; 365: 121584, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38917538

RESUMEN

Rapid urbanization and industrialization have greatly contributed to boosting regional economic growth and mitigating the problem of poverty, but blind expansion of cities and towns has not only caused the inefficient use of urban land resources but also caused the deterioration in the urban ecological environment. Within the current context of emphasizing high-quality development, achieving synergy between the efficient use of urban land and ecological environmental protection is an urgent task for promoting new urbanization construction. In this study, cities in the upper reaches of the Yangtze River (URYR) were adopted as the research object, a theoretical analysis framework for the urban land use efficiency (ULUE) and ecological environment quality (EEQ) was established, the ULUE was measured by using the Slacks-Based Measure (SBM) model, the coupling coordination and interactive corresponding response relationship between the ULUE and EEQ were analyzed, and the influencing factors of the coupling coordination between these two systems were explored by using the random forest model. The following conclusions can be obtained: in 2020, compared with those in 2006, both the ULUE and EEQ were improved, and the two systems exhibited interactions and significant spatiotemporal heterogeneity. The coupling coordination degree (CCD) between the ULUE and EEQ could facilitate maintaining the original state, and the transfer of the CCD exhibited a significant spatial correlation with the state of neighbouring cities. The effect of the ULUE on the EEQ indicated nonlinear characteristics, while the effect of the EEQ on the ULUE was manifested as inhibition initially and then promotion. The random forest regression results showed that the population density, landscape agglomeration and connectivity, market conditions, government intervention, and industrial institutions are the key influencing factors of the CCD. Finally, this study provides policy implications for innovative urban land use modelling, environmental regulation, and industrial transformation and upgrading.


Asunto(s)
Ciudades , Conservación de los Recursos Naturales , Urbanización , Modelos Teóricos , Ecosistema , China
2.
J Environ Manage ; 351: 119798, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38103426

RESUMEN

With climate change and urbanization, flood disasters have significantly affected urban development worldwide. In this study, we developed a paradigm to assess flood economic vulnerability and risk at the urban mesoscale, focusing on urban land use. A hydrological simulation was used to evaluate flood hazards through inundation analyses, and a hazard-vulnerability matrix was applied to assess flood risk, enhancing the economic vulnerability assessment by quantifying the differing economic value and flood losses associated with different land types. The case study of Wangchengpo, Changsha, China, found average total economic losses of 126.94 USD/m2, with the highest risk in the settlement core. Residential areas had the highest flood hazard, vulnerability, and losses (61.10% of the total loss); transportation areas accounted for 27.87% of the total economic losses due to their high flooding depth. Despite low inundation, industrial land showed greater economic vulnerability due to higher overall economic value (10.52% of the total). Our findings highlight the influence of land types and industry differences on flood vulnerability and the effectiveness of land-use inclusion in urban-mesoscale analyses of spatial flood characteristics. We identify critical areas with hazard and economic vulnerability for urban land and disaster prevention management and planning, helping to offer targeted flood control strategies to enhance urban resilience.


Asunto(s)
Desastres , Inundaciones , Desastres/prevención & control , Medición de Riesgo , Urbanización , China
3.
J Environ Manage ; 326(Pt B): 116826, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36442331

RESUMEN

Rapid urbanization poses great challenges to China's urban land use sustainability (ULUS). Land is the essential space to achieve the Sustainable Development Goals (SDGs) of the United Nations, so SDGs provide a new guide to evaluate land use sustainability. However, there is still a lack of SDGs-oriented assessment of urban land use at national level. Moreover, there is still a need to address the problems about the randomness and fuzziness within evaluation, which tends to cause more uncertainties. Here we developed a SDGs-oriented evaluation framework based on the cloud model and derived the spatial and temporal patterns of urban land use sustainability for China at the prefecture-level from 2004 to 2019. Then, we used the McKinsey matrix to classify the types of urban land use sustainability, and examined their main drivers using the Geodetector method. The results showed that the development level of ULUS in China was high in the east and low in the west. High-value hotspots were mainly distributed in primary and secondary urban agglomerations in China. From 2004 to 2019, the development level of ULUS in China gradually increased, but the growth rate slowed down. In 2009 the value of central China exceeded that of the northeast. In contrast, the coordination level of ULUS had declined in more than 50% of Chinese cities during the study period. The high values were in southern China, northeast China, and Chengdu-Chongqing urban agglomeration, while the low values were in central and southern Liaoning and the urban agglomeration in the Central Plains. The development level was mainly controlled by anthropogenic activities and urban development, while natural conditions constrained the improvement of the coordination level. Combining the development and coordination, we found that cities with higher development level often had a wide range of coordination level, and suggestions were put forward for different regions to achieve sustainable land use. Our research provides scientific guidance for China's territory planning and sustainable urban development.


Asunto(s)
Desarrollo Sostenible , Urbanización , Ciudades , China , Naciones Unidas , Conservación de los Recursos Naturales
4.
Environ Monit Assess ; 195(10): 1233, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37728781

RESUMEN

Land use and land cover patterns impact soil properties and negatively affect soil microbial community and related processes. However, the information regarding the influence of urban land use on soil microbial composition and functioning is limited. Here, we investigated the impact of urban land use patterns on soil microbiological parameters by comparing five contrasting anthropogenic land use classes, i.e. agriculture, park, roadside plantation, street green, and bare land. Soil physicochemical properties, basal respiration (BR), microbial biomass carbon (MBC), and enzyme activities were estimated and correlated. The results revealed that soil physicochemical and microbiological properties greatly varied across the five land use classes. Among all the land use types, the roadside plantation had the highest nutrient content, i.e. soil organic carbon (SOC), total nitrogen (TN), and mineral nitrogen (MN) (1.33%, 0.13%, 84.0 mg kg-1, respectively), while the soil functional capacities measured in terms of BR, MBC, microbial quotient (QCO2), soil microbial activity (SMA), and dehydrogenase activity (DHA) (9.90 C µg g-1 h-1, 300 µg g-1, 0.045 µg h-1/ µg MBC, 9.0 µg ml-1, 1.30 TPF g-1 h-1, respectively) were highest in the park. Disturbed street greens were markedly nutrient depleted and apparently exhibited lower microbial activity. Variations in soil BR, MBC, and enzyme activity were revealed to be primarily influenced by soil moisture, available phosphorus, and SOC content. We concluded that the negative impacts of anthropogenic land use soil quality and microbiological functioning can be managed by integrating proper management approaches for various land use classes in urban systems.


Asunto(s)
Carbono , Suelo , Monitoreo del Ambiente , Agricultura , Nitrógeno
5.
Environ Monit Assess ; 195(4): 469, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36920539

RESUMEN

The rapid expansion of cities and continuous urban population growth underscores a need for sustainable urban development. Sustainable development is that which addresses human needs, contributes to well-being, is economically viable, and utilizes natural resources at a degree sustainable by the surrounding environmental systems. Urban green spaces, green roofs, and solar panels are examples of environmentally sustainable urban development (ESUD), or development that focuses on environmental impact, but also presents the potential to achieve social and economic sustainability. The aim of this study was to map and compare amounts of ESUD c. 2010 and c. 2019 through an object-based image analysis (OBIA) approach using National Agricultural Imagery Program (NAIP) aerial orthoimagery for six mid- to large-size cities in the USA. The results of this study indicate a hybrid OBIA and manual interpretation approach applied to NAIP orthoimagery may allow for reliable mapping and areal estimation of urban green space and green roof changes in urban areas. The reliability of OBIA-only mapping and estimation of areal extents of existing green roofs, and new and existing solar panels, is inconclusive due to low mapping accuracy and coarse spatial resolution of aerial orthoimagery relative to some ESUD features. The three urban study areas in humid continental climate zones (Dfa) were estimated to have greater areal extent of new and existing urban green space and existing green roofs, but less areal extent of new green roofs and existing solar panels compared to the three study areas in humid subtropical climate zones (Cfa).


Asunto(s)
Monitoreo del Ambiente , Remodelación Urbana , Humanos , Ciudades , Reproducibilidad de los Resultados , Ambiente , Conservación de los Recursos Naturales
6.
Environ Sci Technol ; 56(7): 4655-4664, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35258974

RESUMEN

Lakes receive and actively process terrestrial dissolved organic matter (DOM) and play an important role in the global carbon cycle. Urbanization results in elevated inputs of nonpoint-source DOM to headwater streams. Retention of water in lakes allows time for alteration and transformation of the chemical composition of DOM by microbes and UV radiation. Yet, it remains unclear how anthropogenic and natural drivers impact the composition and biolability of DOM in non-pristine lakes. We used optical spectroscopy, Fourier transform ion cyclotron mass spectrometry, stable isotopic measurements, and laboratory bioincubations to investigate the chemical composition and biolability of DOM across two large data sets of lakes associated with a large gradient of urbanization in lowland Eastern China, encompassing a total of 99 lakes. We found that increased urban land use, gross domestic products, and population density in the catchment were associated with an elevated trophic level index, higher chlorophyll-a, higher bacterial abundance, and a higher amount of organic carbon with proportionally higher contribution of aliphatic and peptide-like DOM fractions, which can be highly biolabile. Catchment areas, water depth, lake area: catchment area, gross primary productivity, δ18O-H2O, and bacterial abundance, however, had comparatively little linkage with DOM composition and biolability. Urban land use is currently intensifying in many developing countries, and our results anticipate an increase in the level of biolabile aliphatic DOM from nonpoint sources and accelerated carbon cycling in lake ecosystems in such regions.


Asunto(s)
Materia Orgánica Disuelta , Ecosistema , Carbono/análisis , Lagos/química , Ríos
7.
Environ Monit Assess ; 195(1): 219, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36542193

RESUMEN

Urban areas often struggle with deteriorated water quality because of complex interactions between landscape factors and climatic variables. However, few studies have considered the effects of landscape variables on water quality at a sub-500-m scale. We conducted a spatial statistical analysis of six pollutants for 128 water quality stations in four watersheds around Portland, Oregon, using data from 2015 to 2021 for the wet season at two microscales (100 m and 250 m buffers). E. coli was associated with land cover, soil type, topography, and pipe length, while lead variations were best explained by topographic variables. Developed land cover and impervious surface explained variations in nitrate, while orthophosphate was associated with mean elevation. Models for zinc included land cover and topographic variables in addition to pipe length. Spatial regression models better explain variations in water quality than ordinary least squares models, indicating strong spatial autocorrelation for some variables. Our findings provide valuable insights to city planners and researchers seeking to improve water quality in metropolitan areas by manipulating city landscapes.


Asunto(s)
Monitoreo del Ambiente , Calidad del Agua , Oregon , Efectos Antropogénicos , Escherichia coli
8.
Build Environ ; 195: 107729, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36569512

RESUMEN

The outbreak of the COVID-19 epidemic in early 2020 reduced human outdoor activities and changed the spatial-temporal distribution of the population. To find its changes on the impact of urban thermal environment, we applied Pearson correlation analysis and OLS linear regression model from the perspective of urban land use and the local climate zone (LCZ) scheme, and selected Wuhan City in China as a case study. The results showed that the population size decreased in most urban land use and LCZ classes due to the Spring Festival and epidemic effects, which caused residents to leave Wuhan City. As a result, the normalized surface urban heat island changes (SUHInc) decreased by 9.41% at the city level, and a larger SUHInc occurred in commercial and industrial land. Among the LCZ classes, the built-up classes also tended to have a larger SUHInc than the natural land cover classes. However, the population size and human outdoor activity changes did not modify the spatial distribution of the urban thermal environment, because the same trends were observed for various urban land use and LCZ classes, which illustrated that the contribution of anthropogenic heat discharge on the urban thermal environment is relatively weaker. The above findings imply that it is necessary to apply different methods for various urban land uses and alleviate urban heat island.

9.
Ecotoxicology ; 28(5): 578-588, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31140045

RESUMEN

Active urbanization processes exacerbate environmental problems associated with industrial pollution in cities. Urban greening helps reduce level of air pollution and improve microclimate. Selection sensitive plant species (indicators of pollution), and the resistant species (decrease the level pollution) is acute in many countries. The aim of the present work was to establish concentrations of heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, Pb, Co and Cd) in the Siberian larch needles grown in various urban land-use (functional) zones of Ulan-Ude (Russia), as well as to determinate and compare the levels of some biochemical compounds. Based on index of soil contamination, the highest heavy metal pollution was found in the highway and industrial zones. The index of biogeochemical transformation of the needle elements composition ranged from 5.1 (minimal level) to 32.2 (strong level). The most polluted sites were along highways, where Fe, Zn, Cu, Cr, Ni, Pb, and Cd concentration in the needles were up to 2.5-7.7 times than background values. An important role in the protective system of larch is played by pigments, especially Chl b and carotenoids. Their content in the needles is increased by 1.3-2.2 times. Ratio Chl a/b and ∑Chl/carotenoids decrease as compared to background level; in the first case-due to increase of Chl b content, in the second case-increase of carotenoids level. Highest concentrations of proline, condensed tannins and peroxidase activity were found in needles from urban zones connected with high traffic and industrial emission. Based on the Air Pollution Tolerance Index Siberian larch should be considered sensitive species to air pollution and can be recommended as bioindicator.


Asunto(s)
Monitoreo del Ambiente , Larix/metabolismo , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes Atmosféricos/metabolismo , Larix/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Federación de Rusia
10.
Sensors (Basel) ; 19(14)2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31311138

RESUMEN

Urban Land Use/Land Cover (LULC) information is essential for urban and environmental management. It is, however, very difficult to automatically extract detailed urban LULC information from remote sensing imagery, especially for a large urban area. Medium resolution imagery, such as Landsat Thematic Mapper (TM) data, cannot uncover detailed LULC information. Further, very high resolution (VHR) satellite imagery, such as IKONOS and QuickBird data, can only be applied to a small area, largely due to the data unavailability and high computation cost. As a result, little research has been conducted to extract detailed urban LULC information for a large urban area. This study, therefore, developed a three-layer classification scheme for deriving detailedurban LULC information by integrating newly launched Chinese GF-1 (medium resolution) and GF-2 (very high resolution) satellite imagery and synthetically incorporating geometry, texture, and spectral information through multi-resolution image segmentation and object-based image classification (OBIA). Homogeneous urban LULC types such as water bodies or large areas of vegetation could be derived from GF-1 imagery with 16 m and 8 m spatial resolutions, while heterogeneous urban LULC types such as industrial buildings, residential buildings, and roads could be extracted from GF-2 imagery with 3.2 m and 0.8 m spatial resolutions. The multi-resolution segmentation method and a random forest algorithm were employed to perform image segmentation and object-based image classification, respectively. An analysis of the results suggests an overall accuracy of 0.89 and 0.87 were achieved for the second and third level urban LULC classification maps, respectively. Therefore, the three-layer classification scheme has the potential to derive high accuracy urban LULC information through integrating medium and high-resolution remote sensing imagery.

11.
J Environ Manage ; 247: 518-524, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31255966

RESUMEN

This research investigates the impact of land use transformation and anti-flood structural infrastructure on flood situations in four flood-prone districts of Thailand's Ayutthaya: Phra Nakhon Si Ayudhya (PNSA), Bang Ban, Phak Hai, and Sena. PNSA is a UNESCO world heritage city and the cultural and economic hub of Ayutthaya. The finding showed that a large proportion of agricultural land was converted into commercial areas to accommodate economic development and population growth. Furthermore, construction of anti-flood structure infrastructure in PNSA increased flood intensity and duration in three neighboring districts as more floodwater was diverted to the peri-urban area. In addition, this research looks into the social impacts related to land use change and anti-flood structural infrastructure.


Asunto(s)
Inundaciones , Ciudades , Tailandia
12.
Environ Monit Assess ; 190(9): 499, 2018 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-30076475

RESUMEN

The amount and distribution of impervious surfaces are important input parameters of hydrological models, especially in highly urbanized basins. This study tests three different methods to input impervious surface area information to a semi-distributed hydrological model in order to examine their effects on storm flow. The three methods being evaluated include: (1) a constant value for impervious surfaces in the entire urban area, (2) constant values of imperviousness for commercial and residential land uses, respectively, and (3) different imperviousness for the residential land use in each subbasin. Storm flow of the Milwaukee River Basin in southeastern Wisconsin (USA) was modeled using the Hydrological Simulation Program-Fortran. The results show that the three methods resulted in substantially different amounts of storm flow. The storm flow simulated with the third method was the largest and had the largest variability between the subbasins. The differences between the scenarios are generally larger in subbasins with high percentage of urban land use types. The results suggest that the effect of different input methods is amplified in urbanized subbasins and the spatial variability of imperviousness should be commensurate with the spatial variability of the model configuration.


Asunto(s)
Monitoreo del Ambiente , Lluvia , Movimientos del Agua , Hidrología , Modelos Teóricos , Ríos , Urbanización , Wisconsin
13.
Entropy (Basel) ; 20(12)2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-33266714

RESUMEN

One type of fractal dimension definition is based on the generalized entropy function. Both entropy and fractal dimensions can be employed to characterize complex spatial systems such as cities and regions. Despite the inherent connection between entropy and fractal dimensions, they have different application scopes and directions in urban studies. This paper focuses on exploring how to convert entropy measurements into fractal dimensions for the spatial analysis of scale-free urban phenomena using the ideas from scaling. Urban systems proved to be random prefractal and multifractal systems. The spatial entropy of fractal cities bears two properties. One is the scale dependence: the entropy values of urban systems always depend on the linear scales of spatial measurement. The other is entropy conservation: different fractal parts bear the same entropy value. Thus, entropy cannot reflect the simple rules of urban processes and the spatial heterogeneity of urban patterns. If we convert the generalized entropies into multifractal spectrums, the problems of scale dependence and entropy homogeneity can be solved to a degree for urban spatial analysis. Especially, the geographical analyses of urban evolution can be simplified. This study may be helpful for students in describing and explaining the spatial complexity of urban evolution.

14.
Environ Manage ; 60(4): 717-746, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28685244

RESUMEN

Agricultural land conversion is resulting from ongoing complex interaction between the physical environment, policy settings and socio-economic factors. Case studies of the determinants of agricultural land conversion potentially contribute to the analysis of the main causes of land-use change. This can assist authorities and policy makers in understanding the relative importance of a wide range of factors on urban expansion and associated agricultural land-use change. This paper explores the determinants of agricultural land conversion to urban uses in the studied 25 European Union countries between 2000 and 2006. European-level as well as region-specific land-use changes are studied. The research is using the spatial data adapted from European Corine Land Cover maps of 2000 and 2006 and utilised other European sources regarding socio-economic, natural, geological, climate, and policy-related data. The differences in urbanisation processes observed in different regions in Europe emphasise the regional variations of urban conversion process of agricultural land use. This study identifies a combination of socio-economic drivers, policy-related factors, nature and location-based factors as key influences on agricultural land conversion processes in Europe. Specifically we found that the Common Agricultural Policy (CAP) subsidies were influential in curbing urbanisation and reducing agricultural land consumption.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Urbanización , Agricultura/economía , Agricultura/legislación & jurisprudencia , Unión Europea , Recursos Naturales , Factores Socioeconómicos
15.
Environ Monit Assess ; 189(4): 145, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28265835

RESUMEN

Limited data have been published on the chemistry of urban soils and vegetation in the Philippines. The aim of this study is to quantify the concentrations of heavy metals (i.e., Cr, Ni, Cu, Zn, and Pb) in soils and vegetation in the urban landscape of Quezon City, Philippines, and to elucidate the relationships between soil properties and the concentration of heavy metals pertaining to different land uses [i.e., protected forest (LM), park and wildlife area (PA), landfill (PL), urban poor residential and industrial areas (RA), and commercial areas (CA)]. Soil (0-15 cm) and senescent plant leaves were collected and were analyzed for soil properties and heavy metal concentrations. Results revealed that the concentrations of heavy metals (i.e., Cr, Ni, Cu, Zn, and Pb) in urban soils were higher in areas where anthropogenic activities or disturbance (PL, RA, and CA) were dominant as compared to the less disturbed areas (LM and PA). Organic matter and available phosphorous were strongly correlated with heavy metal concentrations, suggesting that heavy metal concentrations were primarily controlled by these soil properties. The average foliar heavy metal concentrations varied, ranging from 0 to 0.4 mg/kg for Cd, 0-10 mg/kg for Cr, 2-22 mg/kg for Cu, 0-5 mg/kg for Pb, and 11-250 mg/kg for Zn. The concentrations of Cd and Cr exceeded the critical threshold concentrations in some plants. Leaves of plants growing in PL (i.e., landfill) showed the highest levels of heavy metal contamination. Our results revealed that anthropogenic activities and disturbance caused by the rapid urbanization of the city are major contributors to the heavy metal accumulation and persistence in the soils in these areas.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Plantas/química , Contaminantes del Suelo/análisis , Ciudades , Filipinas , Suelo/química , Urbanización
16.
Environ Monit Assess ; 189(2): 91, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28144874

RESUMEN

This study attempts to develop a non-path-dependent model for environmental risk management and polycentric urban land-use planning in Gorgan Township area, Iran. Applying three suitability layers of environmental risk (soil erosion, flood risk, fire risk, and land susceptibility), urbanization potential, and integrated surface (environmental risk plus urbanization potential layers), a non-path-dependent Cellular Automata-Markov Chain (CA-MC) model was configured to execute three scenarios of polycentric urban growth allocation. Specifically, the modeling approach improved the traditional functionality of the CA-MC model from a prediction algorithm into an innovative land allocation tool. Besides, due to its flexibility, the non-path-dependent model was able to explicitly include different characteristics of the landscape structure ranging from physical land attributes to landscape functions and processes (natural hazards). Accordingly, three polycentric urban growth allocation efforts were undertaken and compared in terms of connectivity and compactness of the resultant patterns and consumption of other land resources. Based on results, the polycentric allocation procedure based on integrated suitability layer produced a more manageable pattern of urban landscape, while the growth option based on environmental risk layer was more successful for protecting farmlands against excessive urbanization. This study suggests that polycentric urban land-use planning under the strategy of rural land development programs is an available option for designing an urban landscape with lower exposure to natural hazards and more economic benefits to rural residents. Finally, the non-path-dependent modeling is a recommended approach, when highly flexible and interactive decision-support systems as well as trend-breaking scenarios are desired.


Asunto(s)
Algoritmos , Planificación de Ciudades , Monitoreo del Ambiente , Urbanización , Ecosistema , Incendios , Inundaciones , Mapeo Geográfico , Irán , Cadenas de Markov , Riesgo , Análisis Espacio-Temporal
17.
J Environ Sci (China) ; 51: 284-293, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28115140

RESUMEN

Road-deposited sediments (RDS) on urban impervious surfaces are important carriers of heavy metals. Dissolved heavy metals that come from RDS influenced by acid rain, are more harmful to urban receiving water than particulate parts. RDS and its associated heavy metals were investigated at typical functional areas, including industrial, commercial and residential sites, in Guangdong, Southern China, which was an acid rain sensitive area. Total and dissolved heavy metals in five particle size fractions were analyzed using a shaking method under acid rain scenarios. Investigated heavy metals showed no difference in the proportion of dissolved fraction in the solution under different acid rain pHs above 3.0, regardless of land use. Dissolved loading of heavy metals related to organic carbon content were different in runoff from main traffic roads of three land use types. Coarse particles (>150µm) that could be efficiently removed by conventional street sweepers, accounted for 55.1%-47.1% of the total dissolved metal loading in runoff with pH3.0-5.6. The obtained findings provided a significant scientific basis to understand heavy metal release and influence of RDS grain-size distribution and land use in dissolved heavy metal pollution affected by acid rain.


Asunto(s)
Lluvia Ácida , Metales Pesados/química , Modelos Químicos , Contaminantes del Suelo/química , Contaminantes Químicos del Agua/química , China , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis
18.
Ecotoxicology ; 25(3): 608-21, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26892787

RESUMEN

During the spring and fall of 2001 and the spring of 2002 a study was conducted to evaluate the health of the largescale stoneroller (Campostoma oligolepis) populations in streams along an urban land-use gradient. Sites were selected from a pool of naturally similar sub-basins (eco-region, basin size, and geology) of the Mobile River basin (MRB), using an index of urban intensity derived from infrastructure, socioeconomic, and land-use data. This urban land-use gradient (ULUG) is a multimetric indicator of urban intensity, ranging from 0 (background) to 100 (intense urbanization). Campostoma sp. have been used previously as indicators of stream health and are common species found in all sites within the MRB. Endpoints used to determine the effects of urban land-use on the largescale stoneroller included total glutathione, histology, hepatic apoptosis, condition factor and external lesions. Liver glutathione levels were positively associated with increasing urban land-use (r(2) = 0.94). Histopathological examination determined that some abnormalities and lesions were correlated with the ULUG and generally increased in prevalence or severity with increasing urbanization. Liver macrophage aggregates were positively correlated to the ULUG. The occurrence of nucleosomal ladders (indicating apoptotic cell death) did not correspond with urban intensity in a linear fashion. Apoptosis, as well as prevalence and severity of a myxozoan parasite, appeared to have a hormetic dose-response relationship. The majority of the biomarkers suggested fish health was compromised in areas where the ULUG ≥ 36.


Asunto(s)
Cyprinidae/fisiología , Monitoreo del Ambiente , Urbanización , Alabama , Animales , Hormesis , Ríos/química , Contaminantes Químicos del Agua/análisis
19.
Environ Res ; 142: 309-18, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26188632

RESUMEN

BACKGROUND: Global urbanization is increasing rapidly, especially in Asian countries. The health impacts of this unprecedented rate of urbanization are not well understood. Prevalence of asthma is also increasing, especially in cities. METHODS: We explored the effects of urbanicity, based on urban land-use and traffic-related air pollutants (NO2, PM10), on asthma symptoms and diagnosis at a nationally representative level, using individual-level data from the 2008-2010 Community Health Survey data in Korea. We applied logistic regression, adjusting for sex, age, education, smoking status, and household income. To investigate whether different levels of urban intensity (i.e., degree of urbanization) affected the association, we stratified analysis by urban intensity for the subject's residential district: high (≥30% urban), medium (10-30%), and low intensity (<10%). RESULTS: Increased urban land-use was significantly associated with increased risk of asthma symptoms and diagnosis. A 10% increase of urban land-use of a subject's residential district was associated with an odds ratio (OR) of 1.03 (95% CI: 1.02, 1.04) for self-reported physician-diagnosed asthma. However, increased urbanicity is associated with higher risk of asthma in areas with a baseline of low urbanicity, but not in areas with a baseline of high urbanicity. Significant positive associations were also observed for air pollution (PM10 and NO2) with asthma symptoms and diagnosis. CONCLUSIONS: Our findings suggest that increases in urbanicity or air pollution are associated with increased risk of asthma, and that the level of urban intensity affected the associations.


Asunto(s)
Contaminantes Atmosféricos/análisis , Asma/epidemiología , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Urbanización , Adulto , Anciano , Asma/diagnóstico , Ciudades/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , República de Corea/epidemiología , Riesgo , Adulto Joven
20.
Sci Total Environ ; 933: 173165, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38740195

RESUMEN

Microplastics in freshwater ecosystems have gained attention for their potential impact on biodiversity. Rivers are complex and dynamic ecosystems that transport particles and organic matter from the headwaters through watersheds to the ocean. Changes in land use and the presence of wastewater treatment plants (WWTPs) increase the risk of plastic contamination. Simultaneously, hydromorphological features of the watershed can influence the dispersion and retention of microplastics. This study assesses the impact of urban land uses and river hydromorphology on microplastic abundance and spatial distribution in two watersheds with contrasting land uses. Unexpectedly, our findings show that microplastics were widespread throughout watersheds both in water (3.5 ± 3.3 particles/L) and sediments (56.9 ± 39.9 particles/g). The concentration of microplastics in sediments significantly increased in granulometry ranging from 0.5 to 1 mm. Microplastics in running waters are significantly correlated with increasing urban land use coverage. However, the presence and distance of WWTPs did not affect microplastic distribution. In conclusion, contrasting patterns were observed for suspended and sedimented microplastic particles: suspended microplastics were associated with an anthropogenic effect, whereas the concentration of microplastics in sediments was determined by riverbed granulometry. Our results suggest that the interaction of anthropogenic and environmental factors shapes microplastic distribution along the rivers and their subsequent transport toward the coastal ocean. Finally, a review of the current literature reveals the absence of standardization in field and laboratory assessment techniques and measurement units, representing a challenge for intercomparisons of river microplastic studies.

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