Soils were collected with a soil auger and were placed in labeled
plastic bags. The sampling bags were sealed and transported to the
laboratory in a cooler. All samples were maintained at field moist
condition and were stored at 4 ◦C until analyzed. Three separate
sub-samples were taken from each sample. One sub-sample was
used for enzyme assays after passing through a 2-mm sieve. The
second sub-sample was air-dried for water stable aggregates and
soil carbon and nitrogen analysis. The third sub-sample was used
to determine soil moisture content.