Agriculture Reference
In-Depth Information
Chapter 7
Site-Specifi c Soil Cultivation
Hermann J. Heege
Abstract
Site-specifi c soil cultivation has several objectives. In primary cultivation,
the main objective is the control of the working depth. Signals for this control can
be derived from the clay content, the organic matter content, the hydromorphic
properties and the slope of the soil. An algorithm can combine these signals to con-
trol the working depth. The soil resistance to penetration is a suitable control signal
for sensing hardpans below the topsoil, but not for the working depth within the
topsoil, since it depends mostly on the water content.
In secondary cultivation, clod size reduction is an important objective. The site-
specifi c control signals for this can be obtained from the forces acting on a sensing
tine of a cultivator. The standard deviations of the forces can provide for suitable
control parameters.
In stubble- or fallow cultivations either fast- or slow decomposition of the resi-
dues should be aimed at depending on rotations, climate and risk of soil erosion.
The introduction of controlled traffi c farming or of unmanned farm machinery
will promote crop production without tillage well beyond the present use.
Keywords
Controlled-traffi c • Depth-control • Fractionated seedbed • Impact-sensing
• Moisture-line • Tilth-control
7.1
Basic Needs
The need for soil cultivation mainly results from crop- or plant successions in mod-
ern agriculture. In case of perennial vegetation without any abrupt crop- or plant
succession as
e.g.
with permanent grassland, no one thinks about cultivation. Human
