Abstract The impact of rainfall and light interception by litter on maintenance of surface soil water content is determined in an arid rangeland in Khabr National Park in south-east of Iran. Litter weight sampling is done by 90 square plots, each 1 m2, that are randomly placed within site. After determining the intensity of a typical storm of the region (20 mm/h), the rainfall duration requir...

Light models for vegetation canopies based on the turbid medium analogy are usually limited by the basic assumption of random foliage dispersion in the canopy space. The objective of this paper was to assess the effect of three possible sources of non-randomness in tree canopies on light interception properties. For this purpose, four threedimensional (3-D) digitized trees and four theoretical ...

extinction coefficient (k) is an important index that shows the rate of light decrease in canopy. net biomass accumulation is linearly related to cummulative light interception. the slope of this relationship is termed radiation use efficiency. a split plot experiment within randomized complete block design with three replications was conducted in april 2001 in sugar beet research station in ka...

A silicon cell and a radiometer were used to measure the transmission of short wave (0.4—1 pim) and long wave (3-100 ptm) radiation through the coats of sheep and cattle. The reflectivity of the same coats was measured in a spectrophotometer. Measurements of transmission and reflexion were interpreted in terms of a theory of radiation scattering developed (for vegetation) by Cowan (1971), assum...

The performance of a type of fuzzy sliding mode control is researched by considering the nonlinear characteristic of a missile-target interception problem to obtain a robust interception process. The variable boundary layer by using fuzzy logic is proposed to reduce the chattering around the switching surface then is applied to the interception model which was derived. The performances of the s...

The orientation of the new temperature rise maintenance building directly impacts energy consumption heating curing PC components. According to law sun’s motion trajectory and dynamic change characteristics solar radiation energy, this paper takes maximum interception by transparent roof as research goal. study applies thermal process analysis extreme value theory. simplified calculation model ...

Four methods of estimating daily light interception (fisheye photography with image analysis, multiple-light sensors, ceptometer, and point grid) were compared using various apple (Malus domestica Borkh.) tree forms: slender spindle, Yand T-trellises, and vertical palmette. Interactions of tree form, time of day, and atmospheric conditions with light interception estimates were examined. All me...