ABSTRACT
In Table 1 of the original article, the unit mg/L was incorrectly published as ng/L in the aluminum, chloride, sulphate and OM columns.
ABSTRACT
The endorheic basins of the Northern Chilean Altiplano contain saline lakes and salt flats. Two of the salt flats, Gorbea and Ignorado, have high acidic brines. The causes of the local acidity have been attributed to the occurrence of volcanic native sulfur, the release of sulfuric acid by oxidation, and the low buffering capacity of the rocks in the area. Understanding the microbial community composition and available energy in this pristine ecosystem is relevant in determining the origin of the acidity and in supporting the rationale of conservation policies. Besides, a comparison between similar systems in Australia highlights key microbial components and specific ones associated with geological settings and environmental conditions. Sediment and water samples from the Salar de Gorbea were collected, physicochemical parameters measured and geochemical and molecular biological analyses performed. A low diversity microbial community was observed in brines and sediments dominated by Actinobacteria, Algae, Firmicutes and Proteobacteria. Most of the constituent genera have been reported to be either sulfur oxidizing microorganisms or ones having the potential for sulfur oxidation given available genomic data and information drawn from the literature on cultured relatives. In addition, a link between sulfur oxidation and carbon fixation was observed. In contrast, to acid mine drainage communities, Gorbea microbial diversity is mainly supported by chemolithoheterotrophic, facultative chemolithoautotrophic and oligotrophic sulfur oxidizing populations indicating that microbial activity should also be considered as a causative agent of local acidity.
Subject(s)
Bacteria/classification , Lakes/microbiology , Phylogeny , Salts , Sulfur/metabolism , Bacteria/metabolism , Biodiversity , Carbon Cycle , Chile , DNA, Bacterial/genetics , Energy Metabolism , Geologic Sediments/microbiology , Metagenomics , RNA, Ribosomal, 16S/geneticsABSTRACT
The meat quality of Corriedale lambs (40kg live weight) produced in the Mesopotamia region (Argentina) was assessed. These lambs had different finishing diets: only native grass pasture, ground alfalfa and alfalfa-linseed pellet (70/30). Carcass yield, longissimus dorsi area, backfat thickness, marbling, pH, meat and subcutaneous fat color, cooking loss, Warner-Bratzler shear force, fat, protein and moisture content were determined. Lambs finished on alfalfa-linseed pellet had the highest carcasses yield and backfat thickness and their meat had a lighter color (higher L(∗) value), higher marbling and tenderness than meat from lambs reared on native grass pasture. Grass-based finishing can lead to the production of leaner meat, with a more reddish color (higher a(∗) value). The ground alfalfa finishing diet seems to be intermediate between native grass pasture and alfalfa-linseed pellet with respect to carcass yield, backfat and meat color. In addition, the animals fed on ground alfalfa showed the highest muscle area.