User:Jakanoor/sandbox2

Objectives

 * To know its composition of different soil.
 * To advocate farmers about the properties of soils.
 * To classify soil and preparing map of soil fertility status.
 * To evaluate soil fertility status for making fertilizer recommendations.
 * To predict the probable crop response to the applied nutrient.
 * To identify problematic soils i.e., salinity, alkalinity and acidity etc.
 * To suggest and appropriate recommendation & reclamation measures.

Methods
The commonly used soil sampling methods are,


 * 1) Simple random sampling,
 * 2) Stratified random sampling,
 * 3) Systematic sampling and
 * 4) Zig - zag sampling

Sampling Tools

 * 1) Augers
 * 2) Screw auger
 * 3) Post hole auger
 * 4) Tube auger
 * 5) Core sampler
 * 6) Spade / Khurpi
 * 7) Sampling bags
 * 8) Plastic basin / Bucket
 * 9) Labels

Time of sampling

 * Sampling should be done after the harvest of the crop.
 * Collect soil samples two to three months before planting so that planning for soil amendment and fertilizer application can be made.
 * Summer is ideal time for collection of soil sample.
 * Always collect soil sample when the soil is in dry condition.

Quantity of Soil

 * Detailed soil physico - chemical analysis - 500 gm
 * Soil fertility evaluation - 250 gm
 * Pedological studies -1500 gm

Depth of sampling

 * Annual crops (shallow rooted) :  0 - 15 cm
 * Deep rooted : > 15 - 30 cm
 * Horticulture, Plantation and Orchard : 0 - 15, 15 - 30, 30 - 60, 60 - 90, 90 - 120, 120 - 150 and 150 - 180 cm.
 * Pedological studies : 180 cm or deeper
 * Local problem soils : Surface soil: 10 - 30 furrow slice that extend through A1 horizon.
 * Subsoil : Dig a well of 1 m depth. Take soil slice of ½ inches thick below A1 horizon from different depths as follows: 30 - 60, 60 -100 cm.
 * Contaminated soil (Heavy metals) : > 200 cm

Selection of sampling unit
Normally each field may be treated as a sampling unit. A field can be treated as a single sampling unit only if it is relatively uniform and does not generally exceed 0.5 hectare. In a highly levelled land if soil appears to be appreciably uniform, an area of 4 to 5 hectare may represent as a single sampling unit.