A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction...A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction model is necessary to assess the change. Spatial prediction within a Geographic Information System (GIS) using Kriging is a popular stochastic method. The objective of this study was to predict spatial and temporal transformation of a small agricultural watershed—Pipestem Creek in North Dakota;USA using satellite imagery from 1976 to 2015. To enhance the difference between forested land and non-forested land, a spectral transformation method—Tasseled-Cap’s Greenness Index (TCGI) was used. To study the spatial structure present in the imagery within the study period, semivariograms were generated. The Kriging prediction maps were post-classified using Remote Sensing techniques of change detection to obtain the direction and intensity of forest to non-forest change. TCGI generated higher values from 1976 to 2000 and it gradually reduced from 2000 to 2011 indicating loss of forested land.展开更多
Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is a phloem-feeding beetle native to Asia that is causing widespread mortality of ash trees in eastern North America. In this study, we quant...Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is a phloem-feeding beetle native to Asia that is causing widespread mortality of ash trees in eastern North America. In this study, we quantify ash mortality risk associated with potential anthropogenic-induced introduction of Emerald Ash Borer (EAB) in North Dakota. The cohort model is calibrated with data from Ohio using weighting across factors—proximity to existing ash stands, campgrounds, roads and rails—to get a more accurate assessment of overall ash mortality risk. These factors are known to be associated with introduction of EAB to unaffected areas. Two protocols, a) “detection trees” and b) EAB traps are utilized to investigate EAB presence. Ash mortality risk maps such as the ones produced here may guide the placement of traps. Although North Dakota regions of high density ash tree stands are few, the resulting relative ash mortality risk map displays: a) very high risk areas around the Turtle Mountains and Theodore Roosevelt National Park and b) regions of high relative risk along the main riparian corridors. The applicability of risk maps such as the one developed may aid in assessing areas that may require significant monitoring.展开更多
文摘A major threat to biodiversity in North Dakota is the conversion of forested land to cultivable land, especially those that act as riparian buffers. To reverse this trend of transformation, a validation and prediction model is necessary to assess the change. Spatial prediction within a Geographic Information System (GIS) using Kriging is a popular stochastic method. The objective of this study was to predict spatial and temporal transformation of a small agricultural watershed—Pipestem Creek in North Dakota;USA using satellite imagery from 1976 to 2015. To enhance the difference between forested land and non-forested land, a spectral transformation method—Tasseled-Cap’s Greenness Index (TCGI) was used. To study the spatial structure present in the imagery within the study period, semivariograms were generated. The Kriging prediction maps were post-classified using Remote Sensing techniques of change detection to obtain the direction and intensity of forest to non-forest change. TCGI generated higher values from 1976 to 2000 and it gradually reduced from 2000 to 2011 indicating loss of forested land.
文摘Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is a phloem-feeding beetle native to Asia that is causing widespread mortality of ash trees in eastern North America. In this study, we quantify ash mortality risk associated with potential anthropogenic-induced introduction of Emerald Ash Borer (EAB) in North Dakota. The cohort model is calibrated with data from Ohio using weighting across factors—proximity to existing ash stands, campgrounds, roads and rails—to get a more accurate assessment of overall ash mortality risk. These factors are known to be associated with introduction of EAB to unaffected areas. Two protocols, a) “detection trees” and b) EAB traps are utilized to investigate EAB presence. Ash mortality risk maps such as the ones produced here may guide the placement of traps. Although North Dakota regions of high density ash tree stands are few, the resulting relative ash mortality risk map displays: a) very high risk areas around the Turtle Mountains and Theodore Roosevelt National Park and b) regions of high relative risk along the main riparian corridors. The applicability of risk maps such as the one developed may aid in assessing areas that may require significant monitoring.
