Soil enzyme activities under long-term tillage and crop rotation systems in subtropical agro-ecosystems

Abstract

Agricultural practices that reduce soil degradation and improve agricultural sustainability are needed particularly for tropical/subtropical soils. No-tillage planting causes minimal soil disturbance and combined with crop rotation may hold potential to meet these goals. Soil enzyme activities can provide information on how soil management is affecting the potential to perform the processes in soils such as decomposition and nutrient cycling. Soil enzyme activities were investigated in a split-plot experiment (3 replications) where tillage (no till and conventional) was the main plot and crop rotation (soybean/wheat, S/W; maize/wheat, M/ W or cotton/wheat, C/W) was the subplot. The experiment was established in 1976 in southern Brazil. Soil samples were taken at 0-5, 5-10 and 10-20 cm depths in 1997 and 1998. The 0-5 cm layer under NT system showed increases up 68% for amylase, 90% for cellulase, 219% for arylsulfatase, 46% for acid phosphatase, and 61% for alkaline phosphatase. There were significant correlations of soil enzyme activities with total organic C, and C and N microbial biomass. These results showed that NT increased microbial activity and that soil enzyme activity is a sensitive indicator of alteration soil quality by management.

Soil health: looking for suitable indicators. What should be considered to assess the effects of use and management on soil health?

“…Higher enzyme activities under conservationist systems as compared to conventional tillage were also reported (Melero et al, 2008;Qin et al, 2010) in various countries, including Brazil (Mendes et al, 2003;Balota et al, 2004;Carneiro et al, 2004;Carneiro et al, 2009;Peixoto et al, 2010;Lisboa et al, 2012). In general, higher activities of cellulase and amylase are associated with greater amounts of organic C at the topsoil layer.…”

“…They are involved in several metabolic processes and are also responsive to changes in soil use and management (Nannipieri et al, 2002;Acosta-Martínez et al, 2007). Enzymes are catalysts in different reactions during carbon and nutrient cycling in soil (Balota et al, 2004;Sicardi et al, 2004), and also represent the metabolic level of the soil microbial community. They may be free in soil as exoenzymes excreted by plants, animals, and mainly microorganisms (Weaver et al, 1994), linked to cell structures or internally in cells, but later released to the soil after cell lysis and death (Badiane et al, 2001).…”

Soil hydrolase activities and kinetic properties as affected by wheat cropping systems of Northeastern China

“…The type of organic matter was shown to influence the activities of invertase, cellulose, and amylase more than the quantity of organic matter (Balota et al 2004). Although some studies reported that the organic C content was significantly related to the levels of soil enzymes activities (Eivazi and Tabatabai 1990), linear regression analyses in this study showed that the activities of phosphodiesterase were significantly correlated with total P (P < 0.05), activities of arylsulphatase and β-glucosidase with the organic C content (P < 0.05), activities of arylsulphatase, α-glucosidase, and β-glucosidase with the total N content (P < 0.05), urease and arylsulphatase activities with total S content (P < 0.05) in soil.…”

“…Much information is available on the relation between soil managements and soil enzyme activities (Angers et al 1993, Bandick andDick 1999), but very few studies focus on activities and kinetic properties of soil enzymes under different cropping systems in dry hilly areas of China, where plow lands are widely distributed (Dodor and Tabatabai 2003, Balota et al 2004, Green et al 2006. Wheat production in Chaoyang city is 1/3 of that in Liaoning province, which has been one of the higher crop production provinces in China.…”

Biological and other soil parameters response to winter cover crops in a mediterranean irrigated system

“…Most of the correlations were found also in other long-term experiments (Acosta-Martinez et al, 2003;Balota et al, 2014a;Melero et al, 2009). The accumulation of organic matter in the upper soil layer by CC and minimum tillage, and also the contribution of the main crops (root exudates, decomposition of roots and crop residues) stimulated the microbial community and enhanced the enzymes activity (Balota et al, 2004). In 2010, the urease activity was the only enzyme that was not correlated with any other biological parameter, not even with TOC (Roscoe et al, 2000).…”