—We assessed relative abundance, demographic, and reproductive success data for two lizard species in a Northern Arizona ponderosa pine forest, a fire-dependent system unnaturally modified by fire suppression over the past century. During May to October 1997–1999, we employed up to 70 pitfall arrays to sample lizards over 6990 array-days. At each array, we described macro-vegetative cover, stan...

The variation of the directional reflectance of a vegetative canopy with azimuthal view angle becomes prominent when the canopy is illuminated by the sun at large angles from zenith. An extension of a previous directional reflectance model of vegetative canopies is presented to quantify this effect. The results indicate that the cause of the azimuthal variation can be traced to solar flux illum...

Elevation gradients provide opportunities to explore environmental controls on forest structure and functioning. We used airborne imaging spectroscopy and lidar (light detection and ranging) to quantify changes in threedimensional forest structure and canopy functional traits in twenty 25 ha landscapes distributed along a 3300 m elevation gradient from lowland Amazonia to treeline in the Peruvi...

pruning of the plant canopy and paclobutrazol application to the root zone are agronomic practices that improve harvest yield in mango (mangifera indica l.) orchards. to assess the effect of pruning and paclobutrazol treatment on the vegetative and reproductive development of ‘ataulfo’ mango, three pruning dates (20 april, 20 may, and 20 june) and three concentrations of paclobutrazol (pbz) (7....

The aim of this study was to assess the regional effects of fire on the surface cover and forage production of mountainous rangelands of Delfan County, Lorestan province, Iran. The fire took placed in June 2007 with significant effects on the vegetation characteristics in the study area. Four fire affected sites were selected for sampling and a close area without fire was considered as control....

McIntosh, Anne C.S.; Gray, Andrew N.; Garman, Steven L. 2009. Canopy structure on forest lands in western Oregon: differences among forest types and stand ages. Gen. Tech. Rep. PNW-GTR-794. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 35 p. Canopy structure is an important attribute affecting economic and ecological values of forests in the P...

Vegetation cover is the first barrier for the raindrops resulting to the interception and infiltration loss. Interception as one of the main components of ecohydrology equation plays a major role in the water balance of rangelands. However, few studies have been done on the interception of rangeland plants in Iran. This study was carried out to find the interception rate in Astragalus parrowian...

Handheld optical sensors recently have been introduced to the agricultural market. These handheld sensors are able to provide operators with Normalized Difference Vegetative Index (NDVI) data when cloud cover prevents acquisition of satellite or aerial images. This research addressed the sensitivity of the GreenSeeker handheld optical sensor to changes in orientation and height above a ryegrass...