Satellite Land Cover Data Research Articles

Abstract 12096: Satellite-Based Urbanization Measures Are Independent Predictors of Metabolic Syndrome

Introduction: In India, with rapid urbanization, there is a significant increase in the prevalence of cardiovascular diseases at younger ages despite lower rates of obesity. While urbanization has led to nutrition transition, psychosocial stress and behavioral changes, these conventional risk factors do not fully explain the rapid increase in the prevalence. Hypothesis: Urbanization has had a profound impact on the physical environment leading to air pollution, urban heat islands and other effects, which are known to have an impact on metabolic health. Here we assess the impact of built environmental changes on the prevalence of metabolic syndrome (MS) in a rapidly urbanizing population in South India. Methods: Based on census data, a random sample included 8080 participants (20 to 76 years of age; 56% female) from urban, semi-urban, or rural areas spread over 80 x 80 kms. The MODIS satellite land cover data (urban, crops, trees, shrubs and grass land cover) at a 1 km x 1 km resolution was joined to participant's geolocated residential position in ArcGIS. Plus, the distance of the residential location to the urban center was mapped. MS was defined according to the AHA criteria. Multivariable regression models tested the independent association between MS and urban/built environment measures after adjusting for age, sex, physical activity, smoking, alcohol intake, socioeconomic, stress, anxiety, depression, family history of diabetes and hypertension, and energy intake levels. Results: The prevalence was higher in urban (44.6%) and semi-urban communities (35.2%) compared to rural (31.8%). In fully adjusted models, urban participants [OR: 2.11 (1.89, 2.36)], participants in urban land cover [OR: 1.57 (1.38, 1.78)) and those residing within 0 to 20 kms to the urban center [OR: 1.99 (1.7, 2.33)], had significantly higher odds for MS, when compared to rural, participants in crops land cover and those residing 60 to 80 kms from urban center, respectively. Conclusions: There is a significantly higher prevalence of MS in urban regions. After adjusting for traditional risk factors, there is an independent association between urbanization measures and MS suggesting unaccounted factors in the physical or built environment driving the prevalence MS in urban India.

Don't rely too much on trees: Evidence from flood mitigation in China

Combining a popular flood disaster dataset with climate data and satellite land cover data from China, this paper estimates how forests mitigate the frequency of flooding, resulting in two major findings. First, we confirm that an increase in forest area mitigates the possibility of flood occurrence even after controlling for socioeconomic and meteorological variables and time-invariant individual effects. Second, broadleaf trees and mixed-tree forests have a flood mitigation effect, whereas coniferous trees do not; these results are robust against alternative model specifications. This paper newly corroborates the concept of ecosystem-based disaster risk reduction. While there is an emerging consensus that ecosystems can mitigate natural disasters, there is limited evidence on how ecosystems mitigate disasters. To the best of the authors' knowledge, this study is the first to show that the type of forest is critical for mitigating floods in a rigorous econometric way (survival analysis) spanning numerous areas of interest.

Forest and Floods Mitigation: Evidence from China

Combining a popular flood disaster dataset with climate data and satellite land cover data from China, this paper estimates how forests mitigate the frequency of flooding, resulting in two major findings. First, we confirm that an increase in forest area mitigates the possibility of flood occurrence even after controlling for socioeconomic and meteorological variables and time-invariant individual effects. Second, broadleaf trees and mixed-tree forests have a flood mitigation effect, whereas coniferous trees do not; these results are robust against several robustness checks. This paper newly corroborates the concept of ecosystem-based disaster risk reduction. While there is an emerging consensus that ecosystems can mitigate natural disasters, there is limited evidence on how ecosystems mitigate disasters. To the best of the authors' knowledge, this study is the first to show that the type of forest is critical for mitigating floods in a rigorous econometric way spanning numerous areas of interest.

Urbanization and Prevalence of Hypertension Based on 2017 American Heart Association Guideline for High Blood Pressure in the PURSE-HIS Cohort

BACKGROUND: In India, rapid urbanization has had a significant impact on the environment. Little is known about the impact of urban environment on the prevalence of hypertension (HTN). Here we assess the association between HTN and urbanization while controlling for cardiovascular risk factors in the PURSE-HIS cohort, India. METHODS: Based on census data, a random sample included 8080 participants (20–76 yrs of age; 56% female) from urban, semi-urban, or rural areas spread over 80 x 80 km. MODIS satellite land cover data at a 1 km x 1 km resolution was joined to participant's geolocated residential position in ArcGIS to assign urban and rural (crops, trees, shrubs and grass land cover) designations. HTN was diagnosed based on an average of 3 brachial blood pressure measures and the 2017 American Heart Association guideline for HTN diagnosis. Multivariable regression models tested the associations between urbanization measures and HTN, adjusting for age, sex, BMI, physical activity, smoking, socioeconomic, stress, anxiety, cholesterol and sodium intake levels and diabetes status.RESULTS: Based on census, prevalence in urban, semi-urban and rural communities was 49.3%, 41.3% and 31.6%, respectively. Based on MODIS urban, trees, grass and crops land cover, the prevalence was 46.7%, 39.7%, 37.9% and 35%, respectively. In fully adjusted models, urban participants (OR: 2.11 [1.89, 2.36]) and those residing in urban land cover (OR: 1.53 [1.37, 1.69]) had significantly higher odds for HTN when compared to participants in rural areas and crops land cover, respectively.CONCLUSIONS: With close to 50% of the urban population with HTN, there is a significantly higher prevalence of HTN based on the latest (2017) guidelines than previously reported. There is an independent association between urbanization measures and HTN after controlling for cardiovascular risk factors, suggesting unaccounted factors in the urban environment driving the prevalence HTN in urban India.

Regional to Global Biogenic Isoprene Emission Responses to Changes in Vegetation From 2000 to 2015

AbstractIsoprene, a dominant biogenic volatile organic compound that is mainly emitted by trees, has a significant impact on the atmospheric chemistry. Regional to global changes in biogenic isoprene emission associated with vegetation variations between 2000 and 2015 were estimated using the MEGAN model with satellite land cover data for inputs in this study. The satellite data estimates of land cover changes were compared to results from previous investigators that have either conducted regional studies or have used lower resolution land cover data. The analysis indicates that tree coverage increases of >5% occurred in 13% of locations including in central China and Europe. In contrast, a decrease of >5% was observed in about 5% of locations, especially in tropical regions. The trends in global tree coverage from 2000 to 2015 resulted in a global isoprene emission decrease of only 1.5%, but there were significant regional variations. Obvious decreases in tree coverage in some tropical areas (e.g., Amazon Basin, Western Africa, Southeast Asia) resulted in a ~10% reduction of regional isoprene emission due to agricultural expansion. Distinct increments of isoprene emission (5–10%) were mainly found in Northeast China and India and were associated with afforestation efforts. Deforestation and afforestation associated with managed plantations does not only affect the total forest coverage but also impacts average isoprene emission capacity, which can result in accelerated isoprene emission variations. Consequently, isoprene variation assessments are needed that not only account for changes in vegetation fractions but also consider the changes in plant species compositions of forests and other landscapes.

Missing the Forest for the Trees: Balancing Shale Exploration and Conservation Goals Through Policy

Unconventional shale gas activity has presented both challenges and opportunities for conservation. The unique nature of horizontal drilling used in shale exploration allows for a reduction in the footprint of shale related activity in the landscape. However, the existing policies regulating shale activity across the Northeast, particularly in Pennsylvania, largely miss an opportunity to encourage such consolidation, which would result in substantial ecosystem conservation. Using satellite land cover data for the years 2006 and 2011 combined with data on shale drilling activity in Pennsylvania, we show that a consolidation of wells to underutilized well pads would have resulted in a forest conservation gain of over 112,838 acres between 2006 and 2015. While likely an overestimate, this suggests that small changes in policy such as a moving towards a quantity based market mechanism to regulate the number of well pads would result in substantial conservation gains.

Missing the Forest for the Trees: Balancing Shale Exploration and Conservation Goals through Policy

AbstractUnconventional shale gas activity has presented both challenges and opportunities for conservation. The unique nature of horizontal drilling used in shale exploration allows for a reduction in the footprint of shale‐related activity in the landscape. However, existing policies regulating shale activity across the Northeast, particularly in Pennsylvania, largely miss an opportunity to encourage such consolidation, which would result in substantial ecosystem conservation. Using satellite land cover data for the years 2006 and 2011 combined with data on shale drilling activity in Pennsylvania, we show that a consolidation of wells to underutilized well pads would have resulted in a forest conservation gain of over 112,838 acres between 2006 and 2015. While likely an overestimate, this suggests that small changes in policy such as moving toward a quantity‐based market mechanism to regulate the number of well pads would result in substantial conservation gains.

Biogenic carbon fluxes from global agricultural production and consumption

AbstractQuantification of biogenic carbon fluxes from agricultural lands is needed to generate comprehensive bottom‐up estimates of net carbon exchange for global and regional carbon monitoring. We estimated global agricultural carbon fluxes associated with annual crop net primary production (NPP), harvested biomass, and consumption of biomass by humans and livestock. These estimates were combined for a single estimate of net carbon exchange and spatially distributed to 0.05° resolution using Moderate Resolution Imaging Spectroradiometer satellite land cover data. Global crop NPP in 2011 was estimated at 5.25 ± 0.46 Pg C yr−1, of which 2.05 ± 0.05 Pg C yr−1 was harvested and 0.54 Pg C yr−1 was collected from crop residues for livestock fodder. Total livestock feed intake in 2011 was 2.42 ± 0.21 Pg C yr−1, of which 2.31 ± 0.21 Pg C yr−1 was emitted as CO2, 0.07 ± 0.01 Pg C yr−1 was emitted as CH4, and 0.04 Pg C yr−1 was contained within milk and egg production. Livestock grazed an estimated 1.27 Pg C yr−1 in 2011, which constituted 52.4% of total feed intake. Global human food intake was 0.57 ± 0.03 Pg C yr−1 in 2011, the majority of which was respired as CO2. Completed global cropland carbon budgets accounted for the ultimate use of approximately 80% of harvested biomass. The spatial distribution of these fluxes may be used for global carbon monitoring, estimation of regional uncertainty, and for use as input to Earth system models.

Migrating Birds' Use of Stopover Habitat in the Southwestern United States

Abstract. In the arid Southwest, migratory birds are known to use riparian stopover habitats; we know less about how migrants use other habitat types during migratory stopover. Using radar data and satellite land-cover data, we determined the habitats with which birds are associated during migration stopover. Bird densities differed significantly by habitat type at all sites in at least one season. In parts of Arizona and New Mexico upland forest supported high densities of migrants, especially in fall. Developed habitat, in areas with little upland forest, also supported high densities of migrants. Scrub/shrub and grassland habitats supported low to intermediate densities, but because these habitat types dominate the Southwestern landscape, they may provide stopover habitat for larger numbers of migratory birds than previously recognized. These results are complicated by continuing challenges related to target identity (i.e., distinguishing among birds, arthropods and bats). Our results suggest that it i...

Optimal conservation investment for a biodiversity‐rich agricultural landscape*

This study develops a theoretical and empirical framework for optimal conservation planning using satellite land cover data and economic data from a farm survey. A case study is presented for a region within the South‐west Australia Biodiversity Hotspot (Nature403, 853). This Biodiversity Hotspot is a focus for conservation investment as it combines a relatively high level of biodiversity with severe threat to the biodiversity from agriculture. The conservation planning model developed determines the optimal set of bush fragments for conservation. This model can also be used to assess the trade‐off between the budget and a vegetation species metric. Results from the case study show that, without an effective conservation scheme that at least fences fragments, significant plant biodiversity losses will occur in the North East Wheatbelt Regional Organisation of Councils region of the WA wheatbelt over a 10‐year period. A perfect price discriminating auction scheme could reduce the costs of conservation by around 17 per cent relative to a fixed‐payment scheme; however, a fixed payment on outcome (measured as change in the species metric) scheme represents a viable second‐best alternative, to a conservation auction, where conservation spending is spatially targeted.

Topographic normalization of satellite imagery for image classification in northeast India

IRS-LISS-III satellite imagery covering Nongkhyllem Wildlife Sanctuary area located within the Ri-Bhoi District of Meghalaya State, northeast India, was used for analysis of the landcover pattern and vegetation types occurring there. A maximum likelihood classifier was used to generate a supervised classification into land-cover types and the vegetation types within the forested area. The preparation of training data sets used thematic maps of the area, and knowledge accruing from extensive personal field visits. Sample field plots were located at 30 different places in the Sanctuary for classification accuracy assessment. The Normalized Difference Vegetation Index (NDVI) was also computed from LISS-III satellite imagery. A digital elevation model (DEM) of the Sanctuary was generated using a GIS. The DEM was used to test the hypothesis that its joint use with the satellite data would increase classification accuracy. This proved to be the case. Bivariate correlation analysis was performed between spectral and DEM variables to cross-check the results. In the example used, that of the rugged terrain in mountainous parts of northeast India, such integration of satellite land-cover data and DEM information appears to be a necessity in improved land-cover mapping for resource planning and utilization.

Collaboration for community-based wildlife management

We used satellite land cover data and the program FRAGSTATS toquantify land cover types and calculate the amount of forest edge available in suburban and rural regions of northeastern and northwestern Massachusetts. Cover categories included forest cover, open canopy vegetation, and non-deer habitat. We calculated all edge segments where forest cover abutted open canopy cover. Our open canopy vegetation category was calculated both with and without low intensity suburban development. We then compared these findings to movement data from 53 (13 males, 40 females) adult radio-marked white-tailed deerOdocoileus virginianusmonitored biweekly and diurnally from January 2001 to January 2003. The range of movements of suburban deer in eastern Massachusetts showed no difference to that of suburban deer in western Massachusetts (P = 0.7). However, the ranges for suburban deer in both eastern and western Massachusetts were 10 times less than those of deer in rural western Massachusetts (P = 0.001).Our findings suggest that landscape configuration, as described by the amount and distribution of edge due to suburban development, which is related to the amount and distribution of resources such as food and cover, affects migratory behavior of white-tailed deer, allowsdeer to have smaller ranges, and contributes to high deer densities.Inclusion of suburban edge in habitat models will increase our understanding of deer-habitat relationships for management of deer in urbanizing environments.

Modelling Habitat Suitability for Deciduous Forest Focal Species – A Sensitivity Analysis using Different Satellite Land Cover Data

We explored the usefulness of three satellite land cover data sets available to land managers in south-central Sweden for conservation planning using four deciduous forest focal resident bird species with different habitat requirements. Habitat suitability models using empirical species-specific habitat parameters and a Geographic Information System were applied to evaluate and compare the degree of consistency among three different land cover data sets. The study area encompassed 10,000 km2 in a landscape mosaic of managed boreal forests and is within the distribution range of all four focal species. Although the three land cover data sets indicated similar total amounts of deciduous forest, the habitat suitability models showed that different land cover data yielded inconsistent results regarding the amount and distribution of suitable habitat within 5×5 km grid cells. Given this sensitivity to the choice of land cover data sets, the habitat suitability models showed positive relationships among the selected focal species for each land cover data set separately. As expected, decreasing amounts of suitable habitat were identified for species with higher specialisation. Thus, because habitat suitability models are an appropriate way to gain insight into the functionality and connectivity of habitat networks, land cover data must be carefully evaluated and if necessary combined with other landscape information for effective conservation planning.

Collaboration for community-based wildlife management

We used satellite land cover data and the program FRAGSTATS toquantify land cover types and calculate the amount of forest edge available in suburban and rural regions of northeastern and northwestern Massachusetts. Cover categories included forest cover, open canopy vegetation, and non-deer habitat. We calculated all edge segments where forest cover abutted open canopy cover. Our open canopy vegetation category was calculated both with and without low intensity suburban development. We then compared these findings to movement data from 53 (13 males, 40 females) adult radio-marked white-tailed deerOdocoileus virginianusmonitored biweekly and diurnally from January 2001 to January 2003. The range of movements of suburban deer in eastern Massachusetts showed no difference to that of suburban deer in western Massachusetts (P = 0.7). However, the ranges for suburban deer in both eastern and western Massachusetts were 10 times less than those of deer in rural western Massachusetts (P = 0.001).Our findings suggest that landscape configuration, as described by the amount and distribution of edge due to suburban development, which is related to the amount and distribution of resources such as food and cover, affects migratory behavior of white-tailed deer, allowsdeer to have smaller ranges, and contributes to high deer densities.Inclusion of suburban edge in habitat models will increase our understanding of deer-habitat relationships for management of deer in urbanizing environments.

Exploring the relationship between land cover and the distribution of water beetle species (Coleoptera) at the regional scale

The advent of remote-sensed satellite land cover data has provided the opportunity to assess the relationship between invertebrate species distributions and individual land cover types. Water beetle species occur in habitats within specific land cover types and the relationship between the distribution of water beetle species and land covers at the regional scale was investigated using records of 154 species from 1018 sites in north-east England. The land covers of tilled land and urban in the lowlands and of shrub heath and heath grassland in the upland areas proved to be most important in explaining the distribution of species. There were both positive and negative associations between some species and other covers such as woodland and the coast. However, a considerable number of species, generally those with a large number of records, showed no strong relationships with any land cover types. The integration of water beetle species recording data and remote-sensed land cover data as a basis for predicting and monitoring both species distribution and environmental change is discussed.

Hal Shelton Revisited: Designing and Producing Natural-Color Maps with Satellite Land Cover Data - Color Figures

Hal Shelton Revisited: Designing and Producing Natural-Color Maps with Satellite Land Cover Data - Color Figures

Hal Shelton Revisited: Designing and Producing Natural-Color Maps with Satellite Land Cover Data

This paper examines natural-color maps by focusing on the painted map art of Hal Shelton, the person most closely associated with developing the genre during the mid twentieth century. Advocating greater use of natural-color maps by contemporary cartographers, we discuss the advantages of natural-color maps compared to physical maps made with hypsometric tints; why natural-color maps, although admired, have remained comparatively rare; and the inadequacies of using satellite images as substitutes for natural-color maps. Seeking digital solutions, the paper then introduces techniques for designing and producing natural-color maps that are economical and within the skill range of most cartographers. The techniques, which use Adobe Photoshop software and satellite land cover data, yield maps similar in appearance to those made by Shelton, but with improved digital accuracy. Full-color illustrations show examples of Shelton’s maps and those produced by digital techniques.

Sensitivity of a white-tailed deer habitat-suitability index model to error in satellite land-cover data: implications for wildlife habitat-suitability studies

Biologists are increasingly using classified satellite data in habitat analyses, especially due to the recent availability of the National Land Cover Dataset (NLCD) and Gap Analysis Project (GAP) classified maps. However, this type of land-cover data may contain substantial class error incorporated during the classification process. Accuracy assessments provide a measure of class-specific error, but they do not provide information on the spatial distribution of error. Error simulation procedures allow users to gauge the sensitivity of their analyses output to errors in the input land-cover data, although these procedures tend to be computationally intensive. We used pixel- and patch-based error simulation to evaluate the effect of class error in the NLCD on the calculation of habitat-suitability index (HSI) values for white-tailed deer (Odocoileus virginianus) in a high-suitability (agricultural) landscape and a low-suitability (forested) landscape. We incorporated error into landscapes at rates reported in the NLCD accuracy assessment for New York and New Jersey using 2 techniques: pixel-based simulations, in which individual pixels were changed from one cover type to another, and patch-based simulations, in which entire patches were changed. Resulting HSI values were higher in all simulated landscapes than in the original landscapes. The largest increase in HSI, 0.57, occurred using a pixel-based simulation in the low-suitability landscape, due partially to increased interspersion and creation of new one-pixel patches. Patch-based simulations provided a more conservative estimate of the effect of error, an increase in HSI of 0.07–0.28. The difference in HSI between pixel- and patch-based error simulations suggests that the spatial distribution of error in land-cover data may strongly affect the calculation of HSI, especially if the model contains habitat variables related to landscape configuration. We suggest that biologists who make use of classified land-cover data evaluate their analyses for potential sensitivity to error, examine confusion matrices provided with accompanying metadata, and conduct error simulations when feasible.

Improvements in Air Quality Modelling by Using Surface Boundary Layer Parameters derived from Satellite Land Cover Data

Many atmospheric dispersion models include only simpletreatment of surface features to estimate the wind profilesand stability parameters. Detailed characterisation of theland cover, particularly in large and complex urbanconurbations, is especially important, as the surfacefeatures can vary significantly over the area. This paperdiscusses the use of satellite land cover data to derivespatially resolved surface boundary layer (SBL) parameters.These parameters have been used in an air quality model,PEARL (Prediction Air Quality in Urban and RegionalLocations) for estimating monthly and annual COconcentrations. Land cover data, derived from LANDSATThematic Mapper Imagery, has been used to estimate SBLparameters (surface roughness length, albeedo, Bowen ratioand anthropogenic heat flux) for a study area of 10000km2 encompassing Greater London and the surroundingcounties. The SBL parameters have been assigned according tomajor land cover types for the whole area at a spatialresolution of 1 × 1 km. Predictions from two versions of the PEARL model (one with land cover data and one without)have been compared with each other and with measured data forannual and monthly CO concentrations from seven London airquality monitoring sites. This comparison shows thatdifferences between predicted and observed values can bereduced by up to a factor of three. The use of SBLparameters derived from land cover data also yields moredetailed predicted annual CO spatial patterns especially inand around suburban areas. The performance of both versionsof the model for monthly CO concentrations has been comparedwith a range of statistical measures. This comparisonconfirms that improved agreement is observed betweenmodelled and measured monthly CO concentrations when use ismade of spatially resolved SBL parameters.