abstract
Article history:
Received 30 July 2014
Received in revised form 21 May 2015
Accepted 24 May 2015
Available online 24 June 2015
Keywords:
A trash-board
Plowing test
Straw burial
Test-bench
Soil displacement
A minimum amount of straw is still needed to protect soil from wind and water erosion. To better understand the
soil protection effect of straw, the relation of wheat straw displacement and its burial status with plowing speed,
tillage depth and the attachment of trash-board was studied. Three controlling factors were evaluated in a field tillage
testing, i.e., two types of plow (with and without trash-board), three lengths of straw (100 mm, 150 mm, and
250 mm), and various straw conditions. Straw pieces with specific lengths were prepared before the experiment
and used as point tracers to measure the soil and straw displacement. The results indicated that the soil and straw
displacements were significantly different but that the two were interrelated. As the length of straw increased, the
soil displacement decreased due to the forward and lateral displacements; the straw displacement was always significantly
larger than soil displacement, independent of the straw mixtures. Attachment of a trash-board reduced
the soil displacement, but had no apparent effect on the straw displacement. Longer straws were less effective to be
incorporated into the soil than the shorter ones, and the presence of a trash-board led to higher straw burial performance.
The results also indicated that low tillage speed resulted in larger soil fragments and straw displacement
with more straw buried. Moreover, longer straw was less effectively buried than shorter straw at the same speed.
However, straws neighboring the shear were more extensively displaced than those nearby the share bottom