Another way to collect a stool sample is to loosely place plastic wrap across the rim of the toilet, under the seat. Then place the stool sample in a clean, sealable container before taking to the laboratory. Plastic wrap can also be used to line the diaper of an infant or toddler who is not yet using the toilet. The stool should be collected into clean, dry plastic jars with screw-cap lids.
The potential variations in the properties of agricul-. tural soils are less well known. Diaz et al. (1994) have. reported that under a climate change scenario the soil. organic matter content and erosion rate would de-. crease with regard to current values in the Arrecifes. River basin.
If soil pollution is not controlled, it can have adverse effects on the ecological balance and health of living organisms. These effects include increased soil erosion; creation of toxic dust; loss of nutrients in soil; reduced soil fertility; alteration in soil structure; and increase in soil salinity.