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Collection and preparation of soil and water samples for analsis

Sampling Equipments-
  Spade, screw auger (depth wise) or post-hole auger (for moist soil), khudali (pick axe), khurpi, trowel, steel spatula clean plastic bucket, plastic container, cloth bag, information sheet, scale for measuring pit depth marking pencil. 

How to collect the soil sample 
  • Remove or scrap the upper portion  or surface of the soil and remove the crop residues and litters which is on the soil surface.
  • Take pick axe (khudali) and spad with spatula and dig out near about 15-20 cm deep soil width khudali or picking axe. The shape should be V shaped. Remove and reject first digged surface soil. Then collect the soil in the plastic paper or container from selected spots in the field. 
  • Mix all the soil which is taken from different spots in the plastic paper or container. 
  • Avoid soil sampling where  fertilizer and manure applied recently. After mixing the soil sample divide it in four part. Then reject two part form quarter and  take remaining two parts of soil from the plastic  paper  or container .
  • Minimum we have to take 1/2 kg or 1kg soil sample for analysis write the information which is given in sheet.                            
  •   Sample preparation
Drying - Mixed the soil uniformly and spread the soil on polythene for air drying for about 4-5 days in a well-ventilated room of shed.
Grinding -use a mortar and pestle to grind the sample. The grinding breaks down aggregates and mixes the sample. 
Sieving -At least 2mm sieve should be used for sieving soil. Avoid micronutrient contamination do not use a brass, copper or galvanized iron sieve.                                           Technique for  water  sampling -
  • Common sampling tool and accessories. 
  • Clean plastic glass bottles of 500ml capacity. 
Cotton or nylon thread, glass marking pencil and labels  and tags. 

Water  sample collection procedure -
Clean the container before the use and rinsed 3 to 4 times with the water. 
If the source of irritation water is tank,canal or river,  the water sample should be drawn either from a spot, away from the sides or from the midstream with the help of bucket.  The tube well and hand pump are to be run for 10-20 minutes  prior  to, sampling and for open well, several buckets of water have to be thrown out first. About half a liter of the sample is quite sufficient. 
If delay for testing. Add 1 to 3 drops of pure toluene to prevent the bacterial activity. Fill the water sample in the plastic bottles labeled them and sent to laboratory immediately for testing so as to avoid any changes or deterioration in its quality due to the chemical  or microbial activity. 

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