Aerial view of the Chapman College campus, Orange, California, 1966

Aerial view of the Chapman College campus, Orange, California, 1966. Looking diagonally to the northeast. Corner of North Glassell Street and Palm Avenue in lower middle, with the five original buildings just beyond. The old gymnasium is by the oval playing field and stadium. Photographed by Rene Laursen, 702 N. Grand, Santa Ana, California [No. 1499#1].

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, February 23, 1973. Looking north; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 1330 Bristol S. E. #103 - Santa Ana, California 92707." [#9]

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, February 23, 1973. North at left; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 13

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, January, 1973. North at left; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 1330 Palisades #92 - Santa Ana, California 92707." [#1]

Aerial view of the Chapman College residence halls, Orange, California

Aerial view of the Chapman College campus residence halls, Orange, California.

Aerial view of the Chapman College campus, Orange, California

Aerial view of the Chapman College campus, Orange, California. Looking northwest; the Moulton Fine Arts complex is at lower right. After 1978.

Aerial view of the Chapman College campus, Orange, California

Color postcard featuring an aerial view of the Chapman College campus, Orange, California, ca. 1995. Looking north. On message side: "Produced by Wayne Salvatti/Photografx; Copyright Photografx"

Aerial view of the Chapman College campus, Orange, California

Aerial view of the Chapman College campus, Orange, California, looking east. Memorial Hall is in the center, facing lawn and North Glassell Street.

Aerial view of the Hutton Sports Center, Chapman College, Orange, California

Aerial view of the Hutton Sports Center, 219 E. Sycamore Street, Chapman College, Orange, California. The Harold Hutton Sports Center, completed in 1978, is named in honor of this former trustee, and made possible by a gift from his widow, Betty Hutton Williams. Renovated in the mid-1990s.

Niagara aerial photographs, 1921-1991, undated

This collection contains 129 aerial photographs of the Niagara region. The dates vary from 1921-1991, with some photos undated. Some of the areas covered include the Welland Canal, the Queen Elizabeth Way (QEW), Niagara Falls, the Short Hills, and St. Catharines. Most of the photos are black and white.

Low-altitude aerial photography for optimum N fertilization of winter wheat on the North China Plain

Previous research has shown that site-specific nitrogen (N) fertilizer recommendations based on an assessment of a soil’s N supply (mineral N testing) and the crop’s N status (sap nitrate analysis) can help to decrease excessive N inputs for winter wheat on the North China Plain. However, the costs to derive such recommendations based on multiple sampling of a single field hamper the use of this approach at the on-farm level. In this study low-altitude aerial true-color photographs were used to examine the relationship between image-derived reflectance values and soil–plant data in an on-station experiment. Treatments comprised a conventional N treatment (typical farmers’ practice), an optimum N treatment (N application based on soil–plant testing) and six treatments without N (one to six cropping seasons without any N fertilizer input). Normalized intensities of the red, green and blue color bands on the photographs were highly correlated with total N concentrations, SPAD readings and stem sap nitrate of winter wheat. The results indicate the potential of aerial photography to determine in combination with on site soil–plant testing the optimum N fertilizer rate for larger fields and to thereby decrease the costs for N need assessments.

Declines of Aerial Insectivores in North America Follow a Geographic Gradient

North American birds that feed on aerial insects are experiencing widespread population declines. An analysis of the North American Breeding Bird Survey trend estimates for 1966 to 2006 suggests that declines in this guild are significantly stronger than in passerines in general. The pattern of decline also shows a striking geographical gradient, with aerial insectivore declines becoming more prevalent towards the northeast of North America. Declines are also more acute in species that migrate long distances compared to those that migrate short distances. The declines become manifest, almost without exception, in the mid 1980s. The taxonomic breadth of these downward trends suggests that declines in aerial insectivore populations are linked to changes in populations of flying insects, and these changes might be indicative of underlying ecosystem changes.

Determining nugget: sill ratios of standardized variograms from aerial photographs to krige sparse soil data

Maps of kriged soil properties for precision agriculture are often based on a variogram estimated from too few data because the costs of sampling and analysis are often prohibitive. If the variogram has been computed by the usual method of moments, it is likely to be unstable when there are fewer than 100 data. The scale of variation in soil properties should be investigated prior to sampling by computing a variogram from ancillary data, such as an aerial photograph of the bare soil. If the sampling interval suggested by this is large in relation to the size of the field there will be too few data to estimate a reliable variogram for kriging. Standardized variograms from aerial photographs can be used with standardized soil data that are sparse, provided the data are spatially structured and the nugget:sill ratio is similar to that of a reliable variogram of the property. The problem remains of how to set this ratio in the absence of an accurate variogram. Several methods of estimating the nugget:sill ratio for selected soil properties are proposed and evaluated. Standardized variograms with nugget:sill ratios set by these methods are more similar to those computed from intensive soil data than are variograms computed from sparse soil data. The results of cross-validation and mapping show that the standardized variograms provide more accurate estimates, and preserve the main patterns of variation better than those computed from sparse data.