Abstract
β-glucosidase is a key enzyme in the C-cycle, and its activity is strongly influenced by soil management practices and by extrinsic factors such as weather conditions. However, the variability of β-glucosidase activity (BGa) over time and how this variability is affected by tillage and organic fertilization remain poorly elucidated. We investigated how contrasting tillage practices (zero, minimum, conventional or deep) and organic amendment application (dairy cattle slurry or green compost) govern BGa. Strong correlations (r = −0.98; p < 0.001) were found between BGa and preceding cumulative rainfall for soil without crops. Under cropped soil conditions, BGa was 53% greater under zero and minimum tillage than under ploughed treatments (p < 0.05) six years after their applications. These differences could be explained by associated effects of tillage on organic matter content, electrical conductivity and water stable aggregates. The separated organic residue experiment showed that BGa was 36% greater in soil amended with slurry than in soil amended with compost (p < 0.05) five years after their applications. Finally, the response ratio of BGa was calculated in order to study the effect size of each treatment at each sampling period. This simple strategy mitigated the variation on BGa measurements between two sampling periods, and may be applied in future studies to improve the interpretation of other potential soil quality indicators that are sensitive to seasonal changes.
Highlights
Abstract: β-glucosidase is a key enzyme in the C-cycle, and its activity is strongly influenced by soil management practices and by extrinsic factors such as weather conditions
The separated organic residue experiment showed that between β-glucosidase activity (BGa) was 36% greater in soil amended with slurry than in soil amended with compost (p < 0.05) five years after their applications
Introduction β-glucosidase is a key enzyme in the C-cycle, as it is involved in the terminal process of the degradation of cellulose (β-1,4-D-glucose polymer), the most abundant organic compound in the terrestrial biosphere, comprising almost 50% of the biomass synthesized by photosynthetic fixation of CO2 [1]
Summary
Abstract: β-glucosidase is a key enzyme in the C-cycle, and its activity is strongly influenced by soil management practices and by extrinsic factors such as weather conditions. The response ratio of BGa was calculated in order to study the effect size of each treatment at each sampling period This simple strategy mitigated the variation on BGa measurements between two sampling periods, and may be applied in future studies to improve the interpretation of other potential soil quality indicators that are sensitive to seasonal changes. BGa provides an early indication of changes in the status and turnover of soil organic matter (SOM) [3] This enzyme assay is useful because it is strongly and positively correlated with soil fertility variables such as available nitrogen or phosphorus and with other soil quality variables such as soil microbial biomass carbon (MBC) [4,5]. The seasonal changes in biology indicators could be discriminated from true soil-quality variations due to the study treatment
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have