Effects of Cover Crops on Soil Biological and Chemical Quality Parameters.

Degradation of arable soil and planting the same crops reduce ecosystem services. Cover crops could improve soils quality and conserve soil resources. This study was conducted using hairy vetch (Vicia villosa Roth.) and cereal rye (Secale cereale L.) cover crops grown on Mexico silt loam, Menfro silt loam, and sand to evaluate (1) biomass production of cover crops and (2) changes of total C, N, P contents and soil enzyme activities of β-glucosidase, β-glucosaminidase, fluorescein diacetate (FDA) hydrolysis and dehydrogenase. A pot experiment was conducted under greenhouse conditions. Amount of water to be irrigated was calculated according to the plant available water content of each soil type. Half of the plants were fully irrigated while the other half was stressed by applying half volume of the irrigation requirement. Plants were harvested at 6, 9, and 12 weeks after seeding. Preliminary analysis of the data showed greater aboveground biomass of both cover crops in non-stressed treatment grown on Mexico and Menfro silt loam soils compared to the sand. β-glucosaminidase activity was also greater in non-stressed treatment while FDA activity was greater in stressed treatment. Furthermore, FDA activity was higher in the hairy vetch grown soils and β-glucosaminidase activity was higher in cereal rye grown soils. Both enzyme activities were lowest in sand for both species. These results suggest that cover crops may have an effect on soil biological quality parameters and it was influenced by water availability and the soil type.