the aim followed in tillage operations is the preparation of a suitable seedbed. the clod mean weight diameter (mwd) is one of the important tillage quality factors. in this study six sigma methodology was employed to improve the mwd index on the experimental farm of the university of tehran. six sigma is considered as one of the new improving process methods that has gained wide applications i...

performance optimization of chisel tine was proposed by using a chisel plow with adjustable rake angle. effective treatments consisted of soil moisture at 0.5, 0.7 and 0.9 of plastic limit (pl), three rake angle of 30, 40 and 50 degree and speeds of to 3, 5 and 7 km h-1. the measured parameters included draft, soil disturbance area, soil upheaving area, clod mean weight diameter (mwd), specific...

the rehabilitation of sandy desertified land in various dryland ecosystems by different management practices has a great potential to increase aggregate stability and improve soil quality. however, plants in general may have a different ability to sustain soil. the objective was to determine the effects of reclamation practices including haloxylon ammodendron and atriplex canescens plantation o...

the aim of this research was to investigate performance of two combined plows compared to conventional plow. the experiments were conducted in a loamy soil texture with moisture content of 16-18% in karaj region of iran. combination of moldboard+chisel plow and disk plow+chisel plow were compared with conventional moldboard plow as three treatments. data was statistically analyzed using rcbd in...

background and objectives:anionic polyacrylamide application as an organic conditioner alone or in combination with organic material, can improve soil properties. the objective of this study was to investigate the influence some organic conditioners on mean weight diameter (mwd) and dispersible clay percentage (dcp).materials and methods:soil samples collected from the top 30-cm layer of two lo...

introduction: soil structural stability affects the profitability and sustainability of agricultural systems. particle size distribution (psd) and aggregate stability are the important characteristics of soil. aggregate stability has a significant impact on the development of the root system, water and carbon cycle and soil resistance against soil erosion. soil aggregate stability, defined as t...

Robinia pseudoacacia L. (black locust) is a widely planted tree species on Loess Plateau for revegetation. Due to its symbiosis forming capability with arbuscular mycorrhizal (AM) fungi, we explored the influence of arbuscular mycorrhizal fungi on plant biomass, root morphology, root tensile strength and soil aggregate stability in a pot experiment. We inoculated R. pseudoacacia with/without AM...

Soil erosion resistance is influenced by intrinsic soil properties and multiple external factors. This study investigated the effect of tea planting age on to flowing water (reflected rill erodibility (Kr) critical shear stress (τc)) in Three Gorges Reservoir Area. One slope farmland (as control) five plantations cultivated for 3 34 years were selected sampling sites. The results indicated that...