Soil chemical properties affected by cover crops under no-tillage system

Resumen

The use of cover crops in no-tillage systems (NTS) can significantly improve the soil’s fertility. Thus, a study
was performed to evaluate changes in chemical properties of soil caused by cover crops in a no-tillage system. The
field experiment consisted of the following crop rotation: cover crops/rice/cover crops/rice. The experimental
design was in randomized blocks with three replications. Treatments consisted of four cover crops (Brachiaria
brizantha (Hochst. ex A. Rich.) Stapf. cv. Marandu, Brachiaria ruziziensis R. Germ. and C.M. Evrard, Panicum
maximum Jacq. cv. Colonião, and Pennisetum glaucum (L.) R. Br. cv. BN-2) and fallow (control treatment). Soil
samples were collected at the beginning of the summer crop in Oct 2007, Oct 2008 and Oct 2009 at 0-5 cm soil
depth. The use of cover crops provided for a significant increase in the level of nutrients, soil organic matter, cation
exchange capacity, and base saturation in the soil. Soil fertility improved from the first to second year with the
growing of cover crops. The soil under cover crops P. glaucum, B. ruziziensis, and B. brizantha showed higher
fertility than the area under fallow.