Impervious Land Use Research Articles

Spatio-Temporal Heterogeneity of the Urban Heat Effect and Its Socio-Ecological Drivers in Yangzhou City, China

Rapid urbanization and land-use changes may affect the intensity of urban heat islands (UHIs). However, research on the eastern Chinese city of Yangzhou is lacking. Using land cover data and the InVest Urban Cooling model, this study evaluated the spatiotemporal heterogeneity of the UHI effect from 1990 to 2020 and its socioecological drivers in Yangzhou City. Landscape pattern indices such as patch area (CA), percentage of landscape (PLAND), number of patches, patch density, and aggregation index were created using Fragstats 4.2 software. Several social indicators, such as gross domestic product (GDP), night-light index, and population density, were considered to explore their correlation with UHI indicators. During the past three decades, rapid urbanization in Yangzhou has intensified the UHI effect, with the cooling capacity (cc park) and heat mitigation index (HMI) decreasing by ~9.6%; however, the mixed air temperature (T air) has increased by 0.14 °C. The main heat island areas are concentrated in southern Yangzhou, including the Hanjiang and Guangling districts, and have expanded over time. T air was positively correlated with GDP, night-light index, and population density. Moreover, for the impervious land use type, cc park and HMI were negatively correlated with CA and PLAND (p < 0.01). This study contributes to a deeper understanding of the dynamics of UHIs and provides valuable insights for policymakers, urban planners, and researchers striving to create sustainable and climate-resilient cities in Yangzhou.

Taxonomic and functional composition of arthropod assemblages across contrasting three different land use systems

Soil microarthropods play a crucial role in agricultural ecosystems and are necessary for the upkeep of fertile and productive soils. Limited knowledge exists regarding the composition of soil microarthropod communities in changing agricultural and impervious land use systems. Hence, we conducted a comparative analysis of the soil microarthropod diversity in shifting cultivation and impervious land areas, as well as the surrounding natural forest ecosystem in Aizawl, Mizoram, northeast India. Additionally, we evaluated the influence of shifting cultivation and impervious land use regimes on the diversity of these microarthropods. The investigation was done between 2022 and 2023. Soil and litter samples (n=50) were gathered from three distinct land use systems. The soil microarthropods were extracted using the Berlese funnel method. Microarthropod taxa were identified down to the most specific taxonomic level feasible. The variety of soil microarthropods was significantly affected by the practice of shifting cultivation and in the impervious land areas, in comparison to the natural forest system. The soil chemical profiles were notably altered in the shifting agriculture and impermeable land use systems, indicating their detrimental effects on soil microarthropod diversity. This study presented the startling information on the diversity of soil microarthropods and their relationship with the land-use systems in Mizoram, a region in northeast India.

Inconsistent using FLOOD and Flooding Development of EPA SWMM for Assessing Flood Occurrences in Vulnerable Urban Watershed Considering Extreme Rainfall Events

Urban flood, commonly known as urban water congestion, is a type of water hazard that poses significant challenges for urban residents and water management experts. Chittagong, an essential economic hub in Bangladesh, renowned for its role as a port city, comprises a diverse range of land use, including residential, industrial, and commercial sectors. The Chaktai canal, an important element of Chittagong drainage system, is connected to the Karnaphuli river, playing a vital role in managing drainage by handling a substantial portion of the city water. Therefore, this research evaluated the operational efficiency of a specific drainage network under the influence of altered rainfall events using the Storm Water Management Model (SWMM). Using ArcGIS 10.4, the land use pattern of the area was researched, incorporating data from field surveys and secondary sources. SWMM 5.1 integrated watershed data, and further simulation was carried out to estimate runoff in various sub-catchments and drainage network limitations during heavy rain. During the intense monsoon period, the tool determined the average runoff depth, considering backwater effects and robust tidal surges, resulting in a depth of 3.3m compared to 2.6m in the dry season. This research evaluated the influence of impervious land use changes on urban drainage systems. While meteorological factors alone render drainage network sufficient in dry periods, the outfall shows vulnerability during the rainy season, with an allowance of only 0.7m, jeopardizing the catchment through flood. It contributed a schematic sub-catchment representation, emphasizing that flood events depend on volume runoff and peak flow in urban drainage system. SWMM model was used to illustrate the catchment surface runoff and interconnected node depths via conduits, as well as the current catchment scenario comprehensively.

Estimation of entity‐level land use and its application in urban sectoral land use footprint: A bottom‐up model with emerging geospatial data

AbstractLand is an essential resource tomaintain the functioning of the socio‐economic system. Due to sectoral land data limitations, previous studies were primarily restricted to a coarse sectoral level or focused mainly on the global and national scales. However,fine‐scale land use data are required to provide tailored implications for municipal sustainable development. With emerging geographic data and novel methods, including point of interest data, road network data, and natural language processing, a bottom‐up model is developed to estimate the entity‐level artificial impervious land use. Then, we conducted a case study in Shanghai to investigate the spatial features, footprints, and intensities of sectoral land use. Our results indicated that 42 sectors in Shanghai had diverse spatial patterns. The transportation sector had the highest level of agglomeration among all sectors, and the manufacturing industry's adjacent land patches had higher sectoral heterogeneities than the service sector. The transportation sector had the largest direct and embodied land use footprint. The residential‐related sectors had higher land use intensities, while the high value‐added service sectors showed lower land use intensities. Our study indicates that this model offers a novel way of extracting entity‐level spatial land use information and is applicable for socio‐economic metabolism research. Future studies could incorporate remote sensing images and multiple databases to achieve higher resolution.

Impervious Surface Detection in Semi-Urban Environment Using Lidar Data and High Resolution Aerial Photographs

Land use information plays a vital role in effective management of natural resources in any country. It helps manage water, soil, nutrients and plants, animals and provides relationships between land use dynamics, economics and social conditions both in urban and rural areas. The land use and land cover mapping is always a dynamic issue in every country because of the dynamic nature of the land use. Knowledge of land use change patterns has important implications in sustainable development and sustainable environmental management. Impervious surfaces are generally defined as any anthropogenic materials that water cannot infiltrate. Increase in impervious land in urban area is causing high accumulation of storm water during the wet season and causing widespread flooding.This research develops an improved method for impervious land use detection using object–oriented classification system. Although pixel-based approaches have certain strong merits and remain in widespread use, operating at the spatial scale of the pixel can have major drawbacks. Foremost among these is that a pixel’s spatial extent may not match the extent of the land cover feature of interest. That is pixel’s spatial extent may not match the extent of the land cover feature of interest-the problem of mixed pixels may lead to misclassification. Also, when object of interest is considerably larger than the pixel size such as VHR images, urban area comparisons show that the object oriented approach is superior to pixel based approach in terms of accuracy. Object Oriented classification technique is used to separate urban and non-urban features. Negative values of NDVI helped to classify impervious area. Non elevated impervious surfaces are well addressed by NDVI threshold. LiDAR data is used to separate elevated impervious area. By and large, the research shows that impervious land in urban area can be detected using the developed technique with satisfactory accuracy.

Estimating the Variability and Confidence of Land Use and Imperviousness Relationships at a Regional Scale1

Abstract: Impervious cover is a commonly used metric to help explain or predict anthropogenic impacts on aquatic resources; often it is used as a surrogate for intensity of human impacts when evaluating effects on aquatic resources. The most common way to estimate imperviousness is based on relationships with land use. Few studies have evaluated how the relationship between impervious surface and land use varies among geographies with different levels of development and between types of imagery used to assign land use type. In this study, we assess variability in estimates of imperviousness based on two locally available land use datasets: one based on aerial imagery (2‐m resolution) and another based on satellite imagery (30‐m resolution). The ranges and variability in imperviousness within land use categories were assessed at several spatial scales, including within counties, between counties, and between watersheds. Results indicate that there was considerable variability for all developed land use types. Estimated impervious cover often varied over a range of 20‐40% points within a land use category. Furthermore, there were clear spatial patterns both between and within counties, with impervious cover for a given land use type being higher near the urban centers and lower at the margins of development. Estimates of imperviousness for 12 study watersheds indicated that variability increased with increasing watershed development, making it difficult to confidently set management or regulatory targets based on impervious cover. This study suggests that locally derived, high resolution satellite or aerial imagery should be used to estimate imperviousness when a high level of accuracy and precision is required for regulatory or management decisions. Furthermore, the error associated with impervious land use relationships should be accounted for when using impervious cover in runoff or water quality models, or when making management decisions regarding stream health.

Land-use/Land-cover Classification with Multispectral and Hyperspectral EO-1 Data

We compared the capability of the Earth Observing-1 (EO-1) Hyperion hyperspectral (HS) data with that of the EO-1 Advanced Land Imager (ALI) multispectral (MS) data for discriminating different land-use and land-cover classes in Fremont, California. We designed a classification scheme of two levels with level I including general classes and level II including more specific classes. Classification shows that the HS data does not produce better results than the MS data when we directly applied a Mahalanobis distance (MD) classifier. We tested a number of feature reduction and extraction algorithms for the HS image. These algorithms include principal component analysis (PCA), segmented PCA (SEGPCA), linear discriminant analysis (LDA), segmented LDA (SEGLDA), penalized discriminant analysis (PDA) and segmented PDA (SEGPDA). Feature reductions were all followed by an MD classifier for image classification. With SEGPDA, SEGLDA, PDA, and LDA, similar accuracies were achieved while a segmentation-based approach we proposed (SEGPDA or SEGLDA) greatly improved computation efficiency. They all outperformed SEGPCA and PCA by 4 to 5 percent (level II) and 1 to 3 percent (level I) in classification accuracy. For level II classification, overall accuracies obtained by using the features extracted from the HS image were 2 to 3 percent greater than those obtained with the MS image. For various vegetation class and impervious land use categories, the HS data consistently produced better results than the MS data. For level I classification, the HS image generated a thematic map that is � 0.01 greater in kappa coefficient comparing to the MS image. When we collapsed the level II classification map to a level I map, 5 percent (HS) to 7 percent (MS) improvements were achieved.

INFLUENCES OF WATERSHED URBANIZATION AND INSTREAM HABITAT ON MACROINVERTEBRATES IN COLD WATER STREAMS1

ABSTRACT: We analyzed data from riffle and snag habitats for 39 small cold water streams with different levels of watershed urbanization in Wisconsin and Minnesota to evaluate the influences of urban land use and instream habitat on macroinvertebrate communities. Multivariate analysis indicated that stream temperature and amount of urban land use in the watersheds were the most influential factors determining macroinvertebrate assemblages. The amount of watershed urbanization was nonlinearly and negatively correlated with percentages of Ephemeroptera‐Plecoptera‐Trichoptera (EPT) abundance, EPT taxa, filterers, and scrapers and positively correlated with Hilsenhoff biotic index. High quality macroinvertebrate index values were possible if effective imperviousness was less than 7 percent of the watershed area. Beyond this level of imperviousness, index values tended to be consistently poor. Land uses in the riparian area were equal or more influential relative to land use elsewhere in the watershed, although riparian area consisted of only a small portion of the entire watershed area. Our study implies that it is extremely important to restrict watershed impervious land use and protect stream riparian areas for reducing human degradation on stream quality in low level urbanizing watersheds. Stream temperature may be one of the major factors through which human activities degrade cold‐water streams, and management efforts that can maintain a natural thermal regime will help preserve stream quality.

Stream channel enlargement due to urbanization

Stream channel enlargement occurs in response to the change in streamflow regimen accompanying urbanization. This empirical study relates the imputed increase in channel cross‐sectional area to detailed land use data and other information for 78 small watersheds near Philadelphia. Important differences between the effects of various types of impervious land use are observed: large channel enlargement effects are found for sewered streets and area of major impervious parcels such as parking lots, and much smaller effects are observed for unsewered streets and impervious area involving detached houses. Relatively low channel enlargement effects are attributed to all types of impervious development less than 4 years old and also to street and house area more than 30 years old. The influence of impervious development on channel size is found to be significantly related to topographic characteristics of the watershed, to the location of impervious development within the watershed, and to man‐made drainage alterations. Although the relative importance of these interactive factors proves difficult to establish, the most critical determinant of the amount of channel enlargement resulting from a given level of urbanization appears to be basin slope.