The application of spatial technologies for rangeland research and management: State of the art

Anderson, Gerald L.

doi:10.1080/10106049609354543

Cited by 2 publications

(1 citation statement)

References 12 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Global positioning systems can accurately determine the position of every sample point. Combining these technologies provides visual representations of changes through time (Anderson, 1996) and provides the tools necessary to create yield maps.…”

mentioning

confidence: 99%

Yield Mapping to Document Goose Grazing Impacts on Winter Wheat

et al. 2002

View full text Add to dashboard Cite

multiflorum Lam.) seed in the Willamette Valley, Oregon. In other studies, however, geese have reduced the In southwestern Washington and western Oregon, increasing numyield of winter wheat in relation to intensity of grazing bers of wintering Canada geese (Branta canadensis ) graze several farm crops including wheat (Triticum aestivum L.). Our objectives (Allen et al., 1985;Flegler et al., 1987) and to timing of were to develop methods to determine timing, intensity, and locations grazing (Kahl and Samson, 1984). of grazing, and to measure the impact of grazing on grain yield. Aerial Substantial yield losses in grass and cereal crops have photography with ground-truth photography and repeated samplbeen reported at a wide range of grazing levels by geese ing worked well to determine timing, intensity, and locations of graz- (Patterson, 1991). Estimating loss of yield at specific leving. Exclosures served as nongrazed controls. A yield-mapping-systemels of grazing, however, was difficult. Patterson (1991) equipped combine measured yields. All data collection points were suggested exclosures should be used to measure actual spatially located via differential global positioning system (DGPS) yield loss. technology, which allowed us to integrate all data spatially and tempo-Recent technologies such as geographical information rally via geographical information system (GIS) technology. Based systems (GIS) and global positioning systems (GPS) on yield-mapping-system data, goose grazing resulted in grain yield differences ranging from a 16% increase on part of one field to a 25% provide new opportunities to more accurately measure decrease on an area of a field heavily grazed in April, just before geese crop yield and damage caused by wildlife or other facmigrated north. Comparisons of exclosures (nongrazed controls) with tors. Geographical information systems have the ability paired plots provided variable results. Results from paired-plot comto spatially interrelate multiple files or data layers once parisons for three fields during 1998 were 25% reduction, no differthe layers are in geographic registration (Lillesand and ence, and 13% increase in grain yields in the paired plots available Kiefer, 1994). Global positioning systems can accurately for grazing vs. exclosures. Based on yield-mapping-system data, the determine the position of every sample point. Combinsame three fields experienced 19, 7, and 5% grain yield reductions ing these technologies provides visual representations due to goose grazing with the extent of reduction depending on a of changes through time (Anderson, 1996) and provides combination of timing, intensity, and extent of grazing. Paired plots the tools necessary to create yield maps. did not adequately represent grazing impacts on the fields. The yieldmapping system provided nearly complete coverage of the fields andWe designed our study to develop and evaluate methadequately captured grazing impacts. ods to achieve the following objectives: (i) identify locations grazed by geese, (ii) determ...

show abstract

mentioning

confidence: 99%