The Experts below are selected from a list of 39066 Experts worldwide ranked by ideXlab platform
John R. Nuckols - One of the best experts on this subject based on the ideXlab platform.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California. Methods and Results We collected a dense time series of 24 Landsat 5 and 7 images spanning the year 2000 for an agricultural region in Fresno County. We intersected the Landsat time series with the California Department of Water Resources (CDWR) land use map and selected field samples to define the phenological characteristics of 17 major crop types or crop groups. We found the frequent overpass of Landsat enabled detection of crop field conditions (e.g., bare soil, vegetated) over most of the year. However, images were limited during the winter months due to cloud cover. Many samples designated as single-cropped in the CDWR map had phenological patterns that represented multi-cropped or non-cropped fields, indicating they may have been misclassified. Conclusions We found the combination of Landsat 5 and 7 image data would clearly benefit pesticide exposure assessment in this region by 1) providing information on crop field conditions at or near the time when pesticides are applied, and 2) providing information for validating the CDWR map. The Landsat image time-series was useful for identifying idle, single-, and multi-cropped fields. Landsat data will be limited during the winter months due to cloud cover, and for years prior to the Landsat 7 launch (1999) when only one Satellite was operational at any given time. We suggest additional research to determine the feasibility of integrating CDWR land use maps and Landsat data to derive crop maps in locations and time periods where maps are not available, which will allow for substantial improvements to chemical exposure estimation.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California.
Emilie Pecharova - One of the best experts on this subject based on the ideXlab platform.
-
changes in vegetation cover moisture properties and surface temperature of a brown coal dump from 1984 to 2009 using Satellite data analysis
Ecological Engineering, 2012Co-Authors: Jakub Brom, Vaclav Nedbal, Jan Prochazka, Emilie PecharovaAbstract:Abstract This paper presents an evaluation of changes in the performance of the surface of the Velka Podkrusnohorska dump, a brown coal waste dump, over a period of 25 years from 1984 to 2009, on the basis of Satellite data collected by the Landsat Satellite. The changes in vegetation cover, surface moisture and surface temperature were evaluated on the basis of the NDVI index (Normalized Difference Vegetation Index), the NDMI index (Normalized Difference Moisture Index) and the Landsat Satellite thermal band. Due to the intense piling up of extracted material and the removal of vegetation cover, there was a significant increase in surface temperature and a decline in NDVI and NDMI after the study of the dump territory began. The maximum surface temperatures and the minimum values of both indices were established in 2000. The trend of the changes in these values has reversed since 2000, due to intensive reclamation works as well as natural succession. The results indicate a significant role of vegetation cover in the formation of the surface temperature and moisture parameters, and the transformation of solar energy at the surface. We consider that the removal of vegetation cover over vast areas can have an impact on the regional climate and hydrological regime. Moreover, we recommend that emphasis be placed on this effect when planning structures for mining purposes.
Susan K. Maxwell - One of the best experts on this subject based on the ideXlab platform.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California. Methods and Results We collected a dense time series of 24 Landsat 5 and 7 images spanning the year 2000 for an agricultural region in Fresno County. We intersected the Landsat time series with the California Department of Water Resources (CDWR) land use map and selected field samples to define the phenological characteristics of 17 major crop types or crop groups. We found the frequent overpass of Landsat enabled detection of crop field conditions (e.g., bare soil, vegetated) over most of the year. However, images were limited during the winter months due to cloud cover. Many samples designated as single-cropped in the CDWR map had phenological patterns that represented multi-cropped or non-cropped fields, indicating they may have been misclassified. Conclusions We found the combination of Landsat 5 and 7 image data would clearly benefit pesticide exposure assessment in this region by 1) providing information on crop field conditions at or near the time when pesticides are applied, and 2) providing information for validating the CDWR map. The Landsat image time-series was useful for identifying idle, single-, and multi-cropped fields. Landsat data will be limited during the winter months due to cloud cover, and for years prior to the Landsat 7 launch (1999) when only one Satellite was operational at any given time. We suggest additional research to determine the feasibility of integrating CDWR land use maps and Landsat data to derive crop maps in locations and time periods where maps are not available, which will allow for substantial improvements to chemical exposure estimation.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California.
Matthew Airola - One of the best experts on this subject based on the ideXlab platform.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California. Methods and Results We collected a dense time series of 24 Landsat 5 and 7 images spanning the year 2000 for an agricultural region in Fresno County. We intersected the Landsat time series with the California Department of Water Resources (CDWR) land use map and selected field samples to define the phenological characteristics of 17 major crop types or crop groups. We found the frequent overpass of Landsat enabled detection of crop field conditions (e.g., bare soil, vegetated) over most of the year. However, images were limited during the winter months due to cloud cover. Many samples designated as single-cropped in the CDWR map had phenological patterns that represented multi-cropped or non-cropped fields, indicating they may have been misclassified. Conclusions We found the combination of Landsat 5 and 7 image data would clearly benefit pesticide exposure assessment in this region by 1) providing information on crop field conditions at or near the time when pesticides are applied, and 2) providing information for validating the CDWR map. The Landsat image time-series was useful for identifying idle, single-, and multi-cropped fields. Landsat data will be limited during the winter months due to cloud cover, and for years prior to the Landsat 7 launch (1999) when only one Satellite was operational at any given time. We suggest additional research to determine the feasibility of integrating CDWR land use maps and Landsat data to derive crop maps in locations and time periods where maps are not available, which will allow for substantial improvements to chemical exposure estimation.
-
Using Landsat Satellite data to support pesticide exposure assessment in California
International Journal of Health Geographics, 2010Co-Authors: Susan K. Maxwell, Matthew Airola, John R. NuckolsAbstract:Background The recent U.S. Geological Survey policy offering Landsat Satellite data at no cost provides researchers new opportunities to explore relationships between environment and health. The purpose of this study was to examine the potential for using Landsat Satellite data to support pesticide exposure assessment in California.
Samuel Corgne - One of the best experts on this subject based on the ideXlab platform.
-
irrigation history estimation using multitemporal Landsat Satellite images application to an intensive groundwater irrigated agricultural watershed in india
Remote Sensing, 2018Co-Authors: Amit Sharma, Laurence Hubertmoy, Sriramulu Buvaneshwari, M Sekhar, Laurent Ruiz, Soumya Bandyopadhyay, Samuel CorgneAbstract:Groundwater has rapidly evolved as a primary source for irrigation in Indian agriculture. Over-exploitation of the groundwater substantially depletes the natural water table and has negative impacts on the water resource availability. The overarching goal of the proposed research is to identify the historical evolution of irrigated cropland for the post-monsoon (rabi) and summer cropping seasons in the Berambadi watershed (Area = 89 km2) of Kabini River basin, southern India. Approximately five-year interval irrigated area maps were generated using 30 m spatial resolution Landsat Satellite images for the period from 1990 to 2016. The potential of Support Vector Machine (SVM) was assessed to discriminate irrigated and non-irrigated croplands. Three indices, Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI) and Enhanced Vegetation Index (EVI), were derived from multi-temporal Landsat Satellite images. Spatially distributed intensive ground observations were collected for training and validation of the SVM models. The irrigated and non-irrigated croplands were estimated with high classification accuracy (kappa coefficient greater than 0.9). At the watershed scale, this approach allowed highlighting the contrasted evolution of multiple-cropping (two successive crops in rabi and summer seasons that often imply dual irrigation) with a steady increase in the upstream and a recent decrease in the downstream of the watershed. Moreover, the multiple-cropping was found to be much more frequent in the valleys. These intensive practices were found to have significant impacts on the water resources, with a drastic decline in the water table level (more than 50 m). It also impacted the ecosystem: Groundwater level decline was more pronounced in the valleys and the rivers are no more fed by the base flow.
