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This study determined the effectiveness of two Lactobacillus buchneri strains (commercial and indigenous) and sodium benzoate ( SB) in improving the aerobic stability of corn silage under laboratory and field conditions. Two experiments were carried out to test the following treatments: untreated forage, commercial L. buchneri ( CLB), indigenous L. buchneri ( ILB) and SB at a 2 g kg−1 concentration. Both inoculants were applied at a rate of 1 × 106 colony forming units of bacteria per gram of forage. In experiment 1, five replicates of each treatment were ensiled in 15-L laboratory silos. The nutritional, fermentation and microbiological characteristics and aerobic stability of the silage were determined. In experiment 2, the top of a bunker silo was divided into four parts (blocks) along its length before it was sealed, and the treatments were randomly applied. Three bags were buried in each experimental unit (two at the top and one at the core) to determine the loss of dry matter ( DM) and the silage characteristics. In experiment 1, ILB exhibited a lower lactic acid concentration and higher 1,2-propanediol and acetic acid levels, which provided intermediate aerobic stability (67 h). In both experiments, treatment SB exhibited higher residual water-soluble carbohydrate levels and longer aerobic stability relative to the other treatments. In experiment 2, there were lower DM losses and higher digestibility coefficients when SB was applied, similar to that found at the core. Overall, SB was the most effective additive for improving fermentation, preserving nutrients and reducing the aerobic deterioration of corn silage at the top of a bunker silo in a hot-climate environment. [ABSTRACT FROM AUTHOR]

Conservation agriculture through no-till based on cropping systems with high biomass-C input, is a strategy to restoring the carbon (C) lost from natural capital by conversion to agricultural land. We hypothesize that cropping systems based on quantity, diversity and frequency of biomass-C input above soil C dynamic equilibrium level can recover the natural capital. The objectives of this study were to: i) assess the C-budget of land use change for two contrasting climatic environments, ii) estimate the C turnover time of the natural capital through no-till cropping systems, and iii) determine the C pathway since soil under native vegetation to no-till cropping systems. In a subtropical and tropical environment, three types of land use were used: a) undisturbed soil under native vegetation as the reference of pristine level; b) degraded soil through continuous tillage; and c) soil under continuous no-till cropping system with high biomass-C input. At the subtropical environment, the soil under continuous tillage caused loss of 25.4 Mg C ha−1 in the 0–40 cm layer over 29 years. Of this, 17 Mg C ha−1 was transferred into the 40–100 cm layers, resulting in the net negative C balance for 0–100 cm layer of 8.4 Mg C ha−1 with an environmental cost of USD 1968 ha−1. The 0.59 Mg C ha−1 yr−1 sequestration rate by no-till cropping system promote the C turnover time (soil and vegetation) of 77 years. For tropical environment, the soil C losses reached 27.0 Mg C ha−1 in the 0–100 cm layer over 8 years, with the environmental cost of USD 6155 ha−1, and the natural capital turnover time through C sequestration rate of 2.15 Mg C ha−1 yr−1 was 49 years. The results indicated that the particulate organic C and mineral associate organic C fractions are the indicators of losses and restoration of C and leading C pathway to recover natural capital through no-till cropping systems. [Display omitted] • C losses in the subtropical was 97% in the 0–20 cm layer while in tropical environment was 54.1%. • C restorations involve a production system that add high input of biomass-C. • C losses promoted higher economic impact in tropical than in subtropical environment. • The turnover time for subtropical and tropical sites was 77 and 49 years respectively. [ABSTRACT FROM AUTHOR]