Population is a key indicator of socioeconomic development, urban planning and environmental protection, particularly for developing countries like China. But, census data any given area are neither always available nor adequately reflect the internal differences population. The authors tried to overcome this problem by spatializing population across China through utilizing integer night-time imagery (Defense Meteorological Satellite Program/Operational Linescan System, DMSP/OLS) land-use...

Early detection and comprehensive monitoring of inland water algal blooms is fundamental to their effective management mitigation potential ecosystem public health impacts. With the spatial temporal limitations in situ sampling, bloom capabilities have been enhanced greatly by advancements satellite Earth Observation (EO). Three turbid, eutrophic Canadian lakes (Lake Winnipeg (LW); Lake Erie (LE); Woods (LoW)) focus Environment Climate Change Canada (ECCC) research initiatives due concerns...

Since the early 2000s Lake Erie has seen a dramatic increase in phytoplankton biomass, manifested particular by rise severity of cyanobacteria blooms and prevalence potentially toxic taxa such as Microcystis. Satellite remote sensing provided unique capacity for synoptic detection these blooms, enabling spatial temporal trends their extent to be documented. Algorithms satellite algal often rely on single consistent relationship between or cyanobacterial biomass spectral indices Maximum...

Abstract: High spatial resolution hyperspectral data often used in precision farming applications are not available from current satellite sensors, and difficult or expensive to acquire standard aircraft. Alternatively, farming, unmanned aerial vehicles (UAVs) emerging as lower cost more flexible means very high imagery. Miniaturized sensors have been developed for UAVs, but the associated hardware, processing software still prohibitive use by individual farmers small remote sensing firms....

This article investigates the scale issue of inaccurate elevation around buildings in digital surface models (DSMs) and its application building height estimation. DSMs derived from a single pair optical stereo images are affected by occlusions shadows, which lead to indistinct borders DSM. To explore parameters how changes such buildings, 'building–ground difference model' (EDM) has been designed this study. model describes trend differences between neighbours order find stable ground...

This study proposes a multi-criteria and hierarchical evaluation system for building extraction from remotely sensed data. Most of current methods are focused on classification accuracy, while the other dimensions accuracy usually ignored. The proposed consists three components: 1) matched rate, including metrics traditional (e.g., completeness, correctness, quality); 2) shape similarity that describes resemblance between reference extracted buildings, image-based polygon-based metrics; 3)...

Despite significant declines in external phosphorus loads, Lake of the Woods continues to experience severe recurring cyanobacterial harmful algal blooms (cHABs) covering as much 80% lake surface area. Satellite-derived bloom indices were used assess status, trends, and drivers cHAB conditions for period 2002 2021 support developing ecosystem objectives response indicators lake. Areas greatest potential concern, with most prolonged occurrences, southeast Significant decreases suggest may now...

Red and near-infrared line-height algorithms such as the maximum chlorophyll index (MCI) are often considered optimal for remote sensing of chlorophyll-a (Chl-a) in turbid eutrophic waters, under assumption minimal influence from mineral sediments. This study investigated impact turbidity on using MCI a primary example. Inherent optical properties two lakes were used to simulate reflectance spectra. The simulated results: (1) confirmed non-linear relationship between Chl-a MCI; (2) suggested...

This study proposed a natural-rule-based-connection (NRBC) method to connect river segments after water body detection from remotely sensed imagery. A complete network is important for many hydrological applications. While methods using remote sensing are well-developed, less attention has been paid discontinuous and form network. designed an automated NRBC extract by connecting at polygon level. With the assistance of image pyramid, neighbouring connected based on four criteria: gap width...

Water quality is of significant concern and ultimately critical to every Canadian’s life security. Canada has diverse vast landscapes stressors that impact various waterbodies differentially, with influencing factors including contaminant nutrient loads from human activity (mining effluent, wastewater, agricultural runoff, plastics), landscape change (wetland drainage, urbanization) climate (warming water temperatures, longer open seasons, extreme hydrological events, intensifying...

Envisat’s MERIS and its successor Sentinel OLCI have proven invaluable for documenting algal bloom conditions in coastal inland waters. Observations over turbid eutrophic waters, particular, benefited from the band at 708 nm, which captures reflectance peak associated with intense blooms is key to line-height algorithms such as Maximum Chlorophyll Index (MCI). With mission ending early 2012 launched 2016, however, time-series studies relying on these two sensors contend an observation gap...

There are numerous building footprint extraction methods from various data sources and strategies. However, the lack of a consistent standard to evaluate accuracy such impedes comparison different methods, as well further exploration new methods. In this study, comprehensive evaluation system for detection is proposed implemented. order test its performance, four have been designed using LiDAR Colour Infrared Aerial Images. The indices analysis results demonstrate that can provide more...

Urbanization has sprawled rapidly accompanying with transformation of the society, development economy, increase urban population and changes landscape. The Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) a unique capability to detect nocturnal observation artificial lighting which can reflect urbanization level. Most previous studies had focused on pattern in provincial scale. Also, we carried out study cities China by using DMSP/OLS night light imagery....

This letter proposes a multicriteria system to evaluate the accuracy of reconstructed 3-D buildings. Current evaluation methods are derived from 2-D pixel-based evaluation; however, difference between and is not well presented in previous literature. Most building concentrate solely on rooftop while ignoring degree found with regard walls. To address these problems, this designs based three components: volume, surface, point. The volume component represents traditional classification random...

In a digital surface model derived from high-resolution stereo images, the accuracies of building rooftop elevations are usually much lower than that open areas without tall objects. This problem makes height estimation difficult images. The inaccuracy elevation is caused by many factors including shadows, occlusions, smoothing constraints in matching algorithms, and mismatch on extremely high buildings. To improve accuracy elevations, this study enhances existing image methods adding...

This paper proposes an automated water body detection method to delineate detailed bodies from high-resolution satellite images. It consists of three steps: a) coarse mask optical imagery using unsupervised classification; b) refinement backscatter value synthetic aperture radar (SAR) images; and c) advanced morphological filtering produce a final mask. The experiments over Calgary Alberta demonstrate the importance each step show advantages this relative traditional methods, namely, its...

Spatialized population data is much closer to actual circumstances than distribution represented in administrative units. It also crucial for analyzing the relationship among economic growth, environment protection, resource utilization, and other interdisciplinary study. Remote Sensing (RS) Geographic Information System (GIS) are both effective research tools of spatializing census human population. The advance spatial during last several decades based on RS GIS was briefly introduced at...

There are many uncertainties in image segmentation, which should be handled by theories and methods with uncertainty. Cloud model is a kind of effective method to handle uncertainty, considers fuzziness, randomness the connection them. Image segmentation based on one-dimensional cloud processes grayscale histogram, segments images using transformation synthesis, but does not consider spatial information images. The paper proposes two-dimensional model, synthesis. proposed images, has good...