the new device made in this study could calculate the proper position of tillage tools relative to the land surface at each point, and hydraulic operator set its optimum position. the optimum position of tools is calculated by depth control software developed for this device, and its input data were depth for root development. the performance of device was tested on subsoiler for precision till...

knowledge of airflow resistance is an important consideration in designing an appro-priate ventilation system and for proper fan selection. an airflow resistance device was designed and fabricated to measure the airflow resistance of potatoes. the device the composed of an air compressor, a rotameter, a cylindrical bin to contain the potatoes and an inclined u-tube manometer. airflow resistance...

abstract information on spatial and temporal variations of soil hydraulic conductivity (k) is essential to improve soil and water management. however several techniques have been proposed for measuring of soil hydraulic conductivity above water surface table, but reliability and easy use of these methods in various conditions were always concern for engineers. the purposes of this study are mea...

Flood depth has been frequently used to explain the distribution of plant species in seasonally flooded grasslands, but its relation with vegetation production has remained ambiguous. The relationship between flooding and above-ground biomass at the end of the flooding season and during the dry seasonwas studied to assess the impact of reflooding on the Logone floodplain, Cameroon. Above-ground...

response of seed germination of a crop to different environmental conditions is one of the most important determination factors to indicate its ability in competition with weeds. in order to evaluate the effects of water depth and temperature on the germination of different varieties of rice and barnyard grass, an experiment was conducted in the seed laboratory, faculty of agriculture, ferdowsi...