Intermediate snowpack melt-out dates guarantee the highest seasonal grasslands greening in the Pyrenees.

In mountain areas, the phenology and productivity of grassland are closely related to snow dynamics. However, the influence that snow melt timing has on grassland growing still needs further attention for a full understanding, particularly at high spatial resolution. Aiming to reduce this knowledge gap, this work exploits 1 m resolution snow depth and Normalized Difference Vegetation Index observations acquired with an Unmanned Aerial Vehicle at a sub-alpine site in the Pyrenees. During two snow seasons (2019-2020 and 2020-2021), 14 NDVI and 17 snow depth distributions were acquired over 48 ha. Despite the snow dynamics being different in the two seasons, the response of grasslands greening to snow melt-out exhibited a very similar pattern in both. The NDVI temporal evolution in areas with distinct melt-out dates reveals that sectors where the melt-out date occurs in late April or early May (optimum melt-out) reach the maximum vegetation productivity. Zones with an earlier or a later melt-out rarely reach peak NDVI values. The results obtained in this study area, suggest that knowledge about snow depth distribution is not needed to understand NDVI grassland dynamics. The analysis did not reveal a clear link between the spatial variability in snow duration and the diversity and richness of grassland communities within the study area.

Influence of sodium nitrite, temperature, and lactic acid bacteria on the growth of Brochothrix thermosphacta under anaerobic conditions.

In commercial vacuum-packed bologna, growth of Brochothrix thermosphacta was limited at 5 degrees C during a 4-week storage period. Factors controlling the growth of this organism were associated in part with certain lactobacilli isolated from the meat. The lactic acid bacteria associated with the decline of B. thermosphacta and overall spoilage of vacuum-packed bologna were isolated and identified. The principal organisms were Lactobacillus brevis, Lactobacillus buchneri, Lactobacillus plantarum, Lactobacillus viridescens, Leuconostoc mesenteroides, and certain streptococci. In associated growth experiments with B. thermosphacta at 5 and 15 degrees C, L. brevis and L. plantarum showed the greatest antagonism towards the Brochothrix species. Studies with changes in incubation temperatures (5 or 15 degrees C) or nitrite levels (0-50 microgram/mL) indicated that these two factors influence the antagonism but were minor compared with the influence of the lactic acid bacteria.