scholarly journals A Combination Model for Quantifying Non-Point Source Pollution Based on Land Use Type in a Typical Urbanized Area

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 729
Author(s):  
Siru Wang ◽  
Pinzeng Rao ◽  
Dawen Yang ◽  
Lihua Tang
Keyword(s):  
Land Use ◽  
Urban Areas ◽  
Urban Environments ◽  
Point Sources ◽  
Land Use Type ◽  
Pollution Load ◽  
Combination Model ◽  
Urbanized Area ◽  
Nps Pollution ◽  
Poultry Breeding

Water pollution poses threats to urban environments and subsequently impacts the ecological health and sustainable development of urban areas. Identifying the spatiotemporal variation in non-point sources (NPS) pollution is a prerequisite for improving water quality. This paper aimed to assess the NPS pollution load and then recognized the spatiotemporal characteristics of the pollution sources in a typical urbanized area. A combination model based on land use type was used to simulate the NPS pollution load. The results showed the following: (1) ponds and farmlands had higher pollution production intensities than other land use types, but the intensity and magnitude of pollution emissions were generally greater in urban areas; (2) monthly and annual total nitrogen (TN) and total phosphorus (TP) emissions had the same pattern as rainfall, and TN and TP emissions accounted for 56.2% and 58.0%, respectively, of the total in summer; (3) TN pollution was more serious than TP pollution in the study area, especially in farmlands; (4) urban runoff (UR) and livestock and poultry breeding (LPB) were the main sources of NPS, TN and TP emissions in the study area. If these NPS pollutants cannot be removed from this area, a large amount of freshwater is needed to dilute the current rivers to meet the requirement of the fourth category of China national environmental quality standards for surface water. This problem is serious in the control of polluted rivers in many cities throughout China.

scholarly journals A 30-meter resolution national urban land-cover dataset of China, 2000–2015

2019 ◽  
Author(s):  
Wenhui Kuang ◽  
Shu Zhang ◽  
Xiaoyong Li ◽  
Dengsheng Lu
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Urban Areas ◽  
Vegetation Index ◽  
Urban Land ◽  
Google Earth ◽  
Urban Environments ◽  
Urban Land Use ◽  
Environmental Research ◽  
Urban Land Cover

Abstract. Accurate urban land-cover datasets are essential for mapping urban environments. However, a series of national urban land-cover data covering more than 15 years that characterizes urban environments is relatively rare. Here we propose a hierarchical principle on remotely sensed urban land-use/cover classification for mapping intra-urban structure/component dynamics. China's Land Use/cover Dataset (CLUD) is updated, delineating the imperviousness, green surface, waterbody and bare land conditions in cities. A new data subset called CLUD-Urban is created from 2000 to 2015 at five-year intervals with a medium spatial resolution (30 m). The first step is a prerequisite to extract the vector boundaries covered with urban areas from CLUD. A new method is then proposed using logistic regression between urban impervious surface area (ISA) and the annual maximum Normalized Difference Vegetation Index (NDVI) value retrieved from Landsat images based on a big-data platform with Google Earth Engine. National ISA and urban green space (UGS) fraction datasets for China are generated at 30-meter resolution with five-year intervals from 2000 to 2015. The overall classification accuracy of national urban areas is 92 %. The root mean square error values of ISA and UGS fractions are 0.10 and 0.14, respectively. The datasets indicate that the total urban area of China was 6.28 × 104 km2 in 2015, with average fractions of 70.70 % and 26.54 % for ISA and UGS, respectively. The ISA and UGS increased between 2000 and 2015 with unprecedented annual rates of 1,311.13 km2/yr and 405.30 km2/yr, respectively. CLUD-Urban can be used to enhance our understanding of urbanization impacts on ecological and regional climatic conditions and urban dwellers' environments. CLUD-Urban can be applied in future researches on urban environmental research and practices in the future. The datasets can be downloaded from https://doi.org/10.5281/zenodo.2644932.

scholarly journals Quantifying Costs of Urbanisation: Wetland Loss and Impacts in a Rapidly Developing Global City

2020 ◽  
Author(s):  
Harriet Gabites ◽  
Ricky-John Spencer
Keyword(s):  
Land Use ◽  
Surface Area ◽  
Social Cohesion ◽  
Green Infrastructure ◽  
Urban Areas ◽  
Wetland Loss ◽  
Urban Environments ◽  
Urban Biodiversity ◽  
Wetland Inventory ◽  
Chelodina Longicollis

AbstractAs cities grow, natural ecosystems decline through conversion to urban environments. Cities are often viewed as biodiversity wastelands, but they can be hotspots of global biodiversity. Urban biodiversity emphasises two fundamentals. First, people living in cities enjoy wildlife and second, there is virtually no planning for species that co-inhabit our cities. If urban biodiversity was a significant part of planning, then we would be far better at integrating green infrastructure into expanding urban environments.Wetlands are among the most important and productive ecosystems in the world. They are the main suppliers of fresh water for human use and provide habitat to critical fauna and flora. In urban areas they are a vital link to nature and social cohesion. Currently, there is an absence of wetland inventory quantifying loss and changes overtime. Hence the broad impacts of urbanisation on wetland loss are difficult to assess.We explored wetland loss and created a wetland inventory for Western Sydney, Australia, one of the world’s fastest growing urban regions. We used satellite imagery to determine wetland number and type, and calculated changes in wetland surface area from 2010-2017. Broad changes to land use were also quantified. We developed species distribution models of a common urban wetland turtle (Chelodina longicollis) that people interact with regularly or have as pets. Chelodina longicollis utilises both aquatic and terrestrial environments, and we determined if changes in distribution were associated with changes in the wetland inventory and urbanisation.Most local government areas (LGA) experienced a decrease in wetland surface area from 2010-2017, ranging from -1% (Cumberland) to -21% (Blacktown). Majority of LGAs experienced a decrease in wetland density, with wetland densities declining by 25% (Blacktown). All LGAs experienced an increase in urban land use, ranging from 3-12%, which was associated with high rates of wetland loss.Changes in turtle distribution over the decade reflects a southern distribution shift away from where wetland losses were concentrated. We estimated that ∼40,000 individual turtles were displaced or killed due to wetland loss and urbanisation.Urbanisation was the leading cause of wetland loss and degradation in Western Sydney between 2010 and 2017. Wetlands provide critical green infrastructure and significant green space for social cohesion in urban areas. Integration of current wetlands, or the creation of functional wetlands, is key for sustainable development of urban landscapes. Urban wetlands (natural and constructed) may provide “biodiversity arks” for endangered species and facilitate community led conservation programs.

scholarly journals Spatial evaluation of complex non-point source pollution in urban–rural watershed using fuzzy system

2013 ◽  
Vol 16 (1) ◽  
pp. 114-129 ◽  
Author(s):  
Haijun Wang ◽  
Wenting Zhang ◽  
Song Hong ◽  
Yanhua Zhuang ◽  
Hongyan Lin ◽  
...  
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Point Source ◽  
Fuzzy System ◽  
Urban Areas ◽  
Rapid Urbanization ◽  
Nps Pollution ◽  
Urban Rural ◽  
Rural Place ◽  
The Impact

Non-point source (NPS) pollution has become the major reason for water quality deterioration. Due to the differences in the generation and transportation mechanisms between urban areas and rural areas, different models are needed in rural and urban places. Since land use has been rapidly changing, it is difficult to define the study area as city or country absolutely and the complex NPS pollution in these urban–rural mixed places are difficult to evaluate using an urban or rural model. To address this issue, a fuzzy system-based approach of modeling complex NPS pollutant is proposed concerning the fuzziness of each land use and the ratio of belonging to an urban or rural place. The characteristic of land use, impact of city center and traffic condition were used to describe spatial membership of belonging to an urban or rural place. According to the spatial membership of belonging to an urban or rural place, the NPS distributions calculated by the urban model and rural model respectively were combined. To validate the method, Donghu Lake, which is undergoing rapid urbanization, was selected as the case study area. The results showed that the urban NPS pollutant load was significantly higher than that of the rural area. The land usage influenced the pollution more than other factors such as slope or precipitation. It also suggested that the impact of the urbanization process on water quality is noteworthy.

scholarly journals Impact of the COVID-19 Lockdown Measures on Noise Levels in Urban Areas—A Pre/during Comparison of Long-Term Sound Pressure Measurements in the Ruhr Area, Germany

2021 ◽  
Vol 18 (9) ◽  
pp. 4653
Author(s):  
Jonas Hornberg ◽  
Timo Haselhoff ◽  
Bryce T. Lawrence ◽  
Jonas L. Fischer ◽  
Salman Ahmed ◽  
...  
Keyword(s):  
Land Use ◽  
Urban Areas ◽  
Sound Pressure ◽  
Urban Forest ◽  
Noise Pollution ◽  
Time Of Day ◽  
Urban Environments ◽  
Noise Levels ◽  
Ruhr Area ◽  
Main Street

Background: A major source of noise pollution is traffic. In Germany, the SARS-CoV-2 lockdown caused a substantial decrease in mobility, possibly affecting noise levels. The aim is to analyze the effects of the lockdown measures on noise levels in the densely populated Ruhr Area. We focus on the analysis of noise levels before and during lockdown considering different land use types, weekdays, and time of day. Methods: We used data from 22 automatic sound devices of the SALVE (Acoustic Quality and Health in Urban Environments) project, running since 2019 in Bochum, Germany. We performed a pre/during lockdown comparison of A-weighted equivalent continuous sound pressure levels. The study period includes five weeks before and five weeks during the SARS-CoV-2 induced administrative lockdown measures starting on 16 March 2020. We stratified our data by land use category (LUC), days of the week, and daytime. Results: We observed highest noise levels pre-lockdown in the ‘main street’ and ‘commercial areas’ (68.4 ± 6.7 dB resp. 61.0 ± 8.0 dB), while in ‘urban forests’ they were lowest (50.9 ± 6.6 dB). A distinct mean overall noise reduction of 5.1 dB took place, with noise reductions occurring in each LUC. However, the magnitude of noise levels differed considerably between the categories. Weakest noise reductions were found in the ‘main street’ (3.9 dB), and strongest in the ‘urban forest’, ‘green space’, and ‘residential area’ (5.9 dB each). Conclusions: Our results are in line with studies from European cities. Strikingly, all studies report noise reductions of about 5 dB. Aiming at a transformation to a health-promoting urban mobility can be a promising approach to mitigating health risks of noise in cities. Overall, the experiences currently generated by the pandemic offer data for best practices and policies for the development of healthy urban transportation—the effects of a lower traffic and more tranquil world were experienced firsthand by people during this time.

scholarly journals Relationship between Land-Use Type and Daily Concentration and Variability of PM10 in Metropolitan Cities: Evidence from South Korea

Land ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Heechul Kim ◽  
Sungjo Hong
Keyword(s):  
Land Use ◽  
Air Pollution ◽  
South Korea ◽  
Land Use Planning ◽  
Urban Areas ◽  
Land Use Type ◽  
Residential Areas ◽  
Metropolitan Cities ◽  
Significant Difference ◽  
Mixed Land Use

Since urban areas with high air pollution are known to have higher mortality rates compared to areas with less air pollution, accurately understanding and predicting the distribution of particulate matter (PM) in cities is important for urban planning policies that seek to emphasize the health of citizens. Therefore, this study aims to investigate the relationship between PM and land use in metropolitan cities in South Korea using the land-use regression model. We use daily data from the air quality monitoring stations (AQMS) in seven cities in South Korea for the year 2018. For analysis, K-means clustering is employed to identify the land-use pattern surrounding the AQMSs and two log-lin regression models are used to investigate the effects of each land-use type on PM. The findings show a statistically significant difference in PM concentration and variability in the business, commercial, industrial, mixed, and high-density residential areas compared to parks and green areas, and that PM concentration and variability were less in mixed areas than in single land use, thus verifying the effectiveness of a mixed land-use planning strategy. Moreover, microclimatic, seasonal, and regional factors affect PM concentration and variability. Finally, to minimize exposure to PM, various policies such as mixed land use need to be established and implemented differently, depending on the season and time.

scholarly journals Reduction Assessment of Agricultural Non-Point Source Pollutant Loading

2018 ◽  
Author(s):  
YiCheng Fu ◽  
Wenbin Zang ◽  
Jian Zhang ◽  
Hongtao Wang ◽  
Chunling Zhang ◽  
...  
Keyword(s):  
Land Use ◽  
Swat Model ◽  
Land Development ◽  
Status Quo ◽  
Land Use Type ◽  
Buffer Zones ◽  
Pollutant Loading ◽  
Nps Pollution ◽  
The Status ◽  
Pollutant Reduction

Abstract. NPS (Non-point source) pollution has become a key impact element to watershed environment at present. With the development of technology, application of models to control NPS pollution has become a very common practice for resource management and Pollutant reduction control in the watershed scale of China. The SWAT (Soil and Water Assessment Tool) model is a semi-conceptual model, which was put forward to estimate pollutant production & the influences on water quantity-quality under different land development patterns in complex watersheds. Based on the overview of published papers with application of SWAT, the study topics is mainly focus on nutrients, sediments, impoundment & wetlands, hydrologic characteristics, climate change impact, and land-use change impacts. SWAT model was constructed based on rainfall runoff and land use type. The migration-transformation processes of agricultural NPS pollution was simulated and calculated based on the SWAT model. Besides, the loadings and distribution traits of NPS pollutants were also systematically analyzed based on the model. The model was used to quantify the spatial loading intensities of NPS nutrient TN (Total Nitrogen) and TP (Total Phosphorus) to HTRW (Huntai River Watershed) under two scenarios (without & with buffer zones). The SWAT model was validated using actual monitoring information as well as the physical properties of the underlying substrate, hydrology, meteorology and pollutant sources in the HTRW. Scenario settings are mainly based on the changes of surface runoff and sediments, climate and land-use change from different spatial scales, and climatic/physiographic zones. About 1 km within both banks of the trunk streams of the Huntai, Taizi and Daliao rivers, and 5 km surrounding the reservoirs were defined as buffer zones. Existing land use type within the buffer zone was changed to reflect the natural environment. The output of pollutant production under the EPS (Environmental Protection Scenarios) was calculated based on the status quo scenario. Under the status quo scenario, the annual mean modulus of soil erosion in the HTRW was 811 kg/ha, and the output intensities of TN & TP were 19 & 7 kg/ha, respectively. For the unit area, the maximal loading intensities for TN & TP were 365.36 & 259.83 kg/ha, respectively. In terms of spatial distribution, TN & TP loading varied substantially. Under the EPS, the magnitude of N & P production from arable land decreased to a certain degree, and the TN & TP pollution loading per unit area were reduced by 5 & 1 kg/ha annually, respectively. In comparison, the quantity of NPS pollutant production under the EPS was reduced by 21.9 % compared with the status quo scenario, and the quantities of TP & TN decreased by 10.4 % & 25.9 %, respectively. These changes suggested a clear reduction in the export loading of agricultural NPS pollution. Loading intensities analysis showed that land use type is one key factor for controlling NPS pollution. The NPS pollutant loading decreased under the EPS, which showed that environmental protection measure could effectively cut down NPS pollutant loading in HTRW. SWAT was used to assess the reduction of agricultural NPS pollutant. However, SWAT model requires a large amount of data about the watershed being modeled; the data inaccuracy and local factors would impact the accuracy of the SWAT model. To determine the pollutant reduction under different land development patterns, and examine uncertainty of sensitivity parameters, SWAT model in China has wide range of potential application.

scholarly journals Parking Requirement of Institutional Land Use

2022 ◽  
Vol 961 (1) ◽  
pp. 012053
Author(s):  
N M Asmael ◽  
G F Turky
Keyword(s):  
Land Use ◽  
Urban Areas ◽  
City Planning ◽  
Transportation Network ◽  
Land Use Type ◽  
Local Conditions ◽  
Urban City ◽  
Parking Lot ◽  
Demand Rates ◽  
Parking Demand

Abstract Parking demand rates are one of the essential keys to urban city planning around the world. Most cities produced the most suitable parking rates, and models relied on their local conditions, regulations, and people’s habits. In Iraq, there is a lack of parking studies, and therefore, there is a lot of missing information which if be found, will be very valuable for better enhancing and managing the transportation network system. Institutional land use or Government Ministries are the land use type in which this research tries to find its parking generation rates. The goal is to produce models and rates for parking generation by using certain independent variables according to the characteristics of the land-use type. The research study area is the urban areas outside Baghdad CBD. Several sites were selected located in different parts of Baghdad. The number of study sites is three. The collected data about sites are the total number of site employees, site gross floor area, and maximum parked vehicles at each site for an Am and Pm period. Each site has a clear parking lot; besides, the sites were selected relied on particular criteria. The field survey was done at each site for defining days and times. The final stage is a data analysis and producing parking generation rates and models to determine the required parking demand for this land-use type. Statistical analysis of data, model generation, was done by the computer program (SPSS). It concluded that the institutional land use produced 0.94 spaces per 100 m2 of GFA and 0.1 spaces per employee.

Characterization of surface runoff in urban areas

2002 ◽  
Vol 45 (9) ◽  
pp. 249-254 ◽  
Author(s):  
J.S. Choe ◽  
K.W. Bang ◽  
J.H. Lee
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Surface Runoff ◽  
Urban Areas ◽  
Land Use Type ◽  
Industrial Zone ◽  
Physical Treatment ◽  
Industry Type ◽  
Hexane Extracts ◽  
Industrial Zones

Water quality measurements of surface runoff have been carried out in selected residential and industrial zones in urban areas, in which yearly mean precipitation is 1,225 mm. The concentrations of constituents in the surface runoff were measured at sampling sites categorized by land use type in the residential zone, and by industry type in the industrial zone. The water quality constituents of BOD5, COD, SS, NO3-N, TKN, PO4-P, TP, n-Hexane extracts, Cr, Cu, Pb and Fe were analyzed. The event mean concentrations (EMCs) of COD, SS, TKN and TP in the residential zone were 313 mg/L, 279 mg/L, 8.45 mg/L, 1.98 mg/L, and those in the industrial zone were 80 mg/L, 106 mg/L, 5.07 mg/L, and 1.93 mg/L, respectively. Cumulative load curves were created to analyze the first-flushing effect of each pollutant related to the pollutant, the rainfall event, and the land use type. No general relationship between the cumulative load and runoff has been established. The degree of first-flushing effect by constituents was in the following order; TKN>COD>SS>HEM>TP>PO4-P. The correlations between SS and other constituents were analyzed to evaluate the efficiency of the physical treatment process to control the surface runoff in urban areas. Based on the correlation of constituents with SS, high treatment efficiency of SS, heavy metals, organic matter, and TP was expected. The unit pollutant loading rates of COD, SS, TKN, TP, Cr and Pb in the residential zone were 2,392, 2,130, 64.6, 15.1, 0.31, and 1.83 kg/ha/yr, and those in the industrial zone were 612, 812, 38.7, 14.8, 0.51 and 0.82 kg/ha/yr, respectively.

scholarly journals Leaf Functional Traits Vary in Urban Environments: Influences of Leaf Age, Land-Use Type, and Urban–Rural Gradient

2021 ◽  
Vol 9 ◽  
Author(s):  
Yuebo Su ◽  
Bowen Cui ◽  
Yunjian Luo ◽  
Jia Wang ◽  
Xuming Wang ◽  
...  
Keyword(s):  
Land Use ◽  
Functional Traits ◽  
Stomatal Density ◽  
Leaf Age ◽  
Urban Environments ◽  
Land Use Type ◽  
Leaf Functional Traits ◽  
Land Use Types ◽  
Urban Rural ◽  
The City

An increasing number of studies have focused on the response and adaptation of plants to urbanization by comparing differences in leaf functional traits between urban and rural sites. However, considerable uncertainties remain because differences in land-use type have not frequently been taken into account when assessing the effect of urbanization on leaf traits. In this study, we sampled the needles of Chinese pine (Pinus tabuliformis Carr.) in areas with three land-use types (roadsides, parks, and neighborhoods) along an urban–rural gradient in Beijing, China to determine the effect of urbanization on leaf functional traits. There were significant differences in the values of leaf functional traits between the needles of the current and previous year and across land-use types. Pines growing on roadsides had leaves with smaller length, width, and area, as well as lower stomatal density, compared with those growing in parks and neighborhoods. This implies that on roadsides, plant capacity to acquire resources (e.g., light and carbon dioxide) was degraded. Stomatal density, leaf width, and leaf P concentration increased with increasing distance from the city center, while leaf K concentration decreased with increasing distance from the city center. Importantly, there were significant differences in the urban–rural gradient of leaf functional traits between leaves of different ages, and across land-use types. Leaf age was the most important factor influencing leaf nutrient traits, while land-use type was the most important factor influencing leaf morphological traits in urban environments. Thus, considering the effects of the plant characteristic and land-use type on traits is important for assessing the urban–rural gradients of plant functional traits.

scholarly journals Monitoring of Land Use/Land-Cover Changes in the Arid Transboundary Middle Rio Grande Basin Using Remote Sensing

2018 ◽  
Vol 10 (12) ◽  
pp. 2005 ◽  
Author(s):  
Stanley Mubako ◽  
Omar Belhaj ◽  
Josiah Heyman ◽  
William Hargrove ◽  
Carlos Reyes
Keyword(s):  
Public Policy ◽  
Land Use ◽  
Land Cover ◽  
Urban Development ◽  
Urban Areas ◽  
Rio Grande ◽  
Point Sources ◽  
Natural Ecosystems ◽  
Rio Grande Basin ◽  
Middle Rio Grande

Expanding urbanization in highly fragile desert environments requires a thorough understanding of the current state and trends of land uses to achieve an optimal balance between development and the integrity of vital ecosystems. The objectives of this study are to quantify land use change over the 25-year period 1990–2015 and analyze temporal and spatial urbanization trends in the Middle Rio Grande Basin. We conclude by indicating how the results can inform on-going water resource research and public policy discussion in an arid region. Results show that the predominant upland mixed vegetation land cover category has been steadily declining, giving up land to urban and agricultural development. Urban development across the region of interest increased from just under three percent in 1990 to more than 11 percent in 2015, mainly around the major urban areas of El Paso, Ciudad Juárez, and Las Cruces. Public policy aspects related to results from this study include transfer of water rights from agriculture to land developers in cities, higher risk of flooding, loss of natural ecosystems, and increased water pollution from point and non-point sources. Various stakeholders can find the study useful for a better understanding of historical spatial and temporal aspects of urban development and environmental change in arid regions. Such insights can help municipal authorities, farmers, and other stakeholders to strike a balance between development needs and protecting vital ecosystems that support the much needed development, especially in regions that are endowed with transboundary natural resources that often are incompletely represented in single nation data.

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