Agricultural intensification has led to soil degradation, reducing fertility and microbial diversity, compromising long-term productivity. Biochar and plant growth-promoting rhizobacteria (PGPR) are proposed as sustainable soil amendments, but their combined effects in agricultural semi-arid soils are poorly understood. This study assessed the interactive effects of poultry manure-derived biochars produced at 500 degrees C (BC500) and 700 degrees C (BC700), with and without Bacillus velezensis inoculation, on soil chemical properties, enzymatic activities, microbial communities and wheat (Triticum aestivum) performance under greenhouse conditions. The effects of biochar were the dominant drivers across all variables analysed, whereas those of PGPR inoculation were less evident. Biochar addition significantly altered soil chemistry, increasing pH, cation exchange capacity and nutrient availability. Enzymatic activities related to C, N and P cycling were also stimulated, with BC500 enhancing beta-glucosidase activity and BC700 promoting phosphomonoesterase and xylosidase activities. High-throughput sequencing revealed that biochar and PGPR modulated microbial community structure and diversity. The BC500 treatments were associated with Planctomycetota, whereas the BC700 enriched Actinobacteriota, Proteobacteria and Firmicutes. PGPR inoculation increased Shannon diversity and evenness, suggesting an enhanced microbial balance, although its persistence appeared to be limited. Wheat responses differed according to biochar type: BC500 did not significantly affect performance compared with the control, whereas BC700 reduced shoot and root biomass, grain dry weight and grain number. B. velezensis inoculation modestly improved root growth and grain biomass, particularly in the absence of biochar, but did not consistently interact synergistically with biochar amendments. Finally, multivariate analyses suggest that the chemical changes induced in the soil by biochar addition are likely the main drivers of wheat performance in these environments. In addition, the results indicate that the effects of biochar depend strongly on pyrolysis temperature, with moderate-temperature biochars preserving soil functionality while maintaining crop productivity comparable to the control. The limited effects of B. velezensis highlight the need for improved inoculation strategies to ensure long-term persistence. These findings emphasise the importance of tailoring biochar properties and microbial applications to local soil conditions for sustainable crop management.
Human-modified landscapes increasingly bring wildlife, domestic animals, and humans into spatial overlap, with important consequences for the composition and distribution of parasite communities. We characterize the gastrointestinal parasite communities in free-ranging black-horned capuchins [hereafter capuchin monkey(s); Sapajus nigritus cucullatus], domestic dogs (Canis lupus familiaris), and cattle (Bos taurus) living in a human-wildlife interface in the Atlantic Forest of Misiones, Argentina. We analyzed 197 fecal samples from capuchin monkeys, 71 from domestic dogs, and 29 from cattle collected across six study sites and conducted 50 semi-structured interviews with residents to characterize domestic animal management practices. We recorded 15 parasite taxa in capuchin monkeys, including protozoans, nematodes, acanthocephala, and cestodes, several of which had not been previously reported for this species. Interviews revealed limited implementation of preventive veterinary care, widespread free-ranging domestic dogs, and frequent spatial overlap between domestic animals and capuchin monkeys. Our results underscore the value of descriptive parasitological surveys for identifying parasite groups at interface contexts that warrant further investigation using molecular approaches, as well as informing surveillance and management priorities within a One Health framework.
A fossil specimen of angiosperm wood from the Corral Quemado Formation (Late Pliocene), Santa Mar & iacute;a Group, exposed at Puerta de Corral Quemado, Department of Bel & eacute;n, Catamarca, Argentina, was investigated. A multi-technique analytical approach was applied to elucidate the processes of silicification and mineral alteration, reconstruct palaeoenvironmental conditions and evaluate interfacies adsorption mechanisms in palaeo-xylological systems. X-ray photoelectron spectroscopy (XPS), x-ray fluorescence (XRF) and x-ray diffraction (XRD) determined the elemental composition and mineral crystallography, while petrographic microscopy, scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy (SEM-EDS), and confocal Raman spectroscopy (CRS) refined the morphological and phase characterisation. The results indicate a mineral composition consistent with hydro-geochemical fluctuations in piedmont and alluvial environments. The coexistence of iron oxides, microcrystalline silica, and traces of heavy metals reflects alternating wet and dry conditions. The integration of XPS, XRF and CRS enabled the detection of relict organic carbon, Fe3+ and adsorption kinetics at the silica-carbon-iron interfaces. These findings reveal taphonomic patterns associated with silicification and the exceptional preservation of organic microstructures. This study provides new insights into the physicochemical and mineralogical mechanisms driving silicification in fossil woods, contributing to palaeoclimatic and palaeoenvironmental interpretations of the Neogene xylotaphoflora of the Santa Mar & iacute;a Basin in the Sierras Pampeanas, north-western Argentina.
Hantaviruses infect a wide range of vertebrate hosts. In the Americas, Orthohantavirus species pose a major public health concern due to their ability to cause Hantavirus Cardiopulmonary Syndrome (HCPS). Given the lack of approved vaccines and specific treatments for HCPS, identifying circulating orthohantavirus genotypes and their hosts, along with estimating prevalence, is essential for designing effective preventive strategies. The objectives of this study were: (1) to identify the orthohantavirus hosts, (2) to determine the circulating orthohantavirus genotypes, (3) to assess the population structure and dynamics of Akodon montensis, (4) to characterize the rodent communities, and (5) to evaluate associations between A. montensis abundance and environmental variables in two protected natural areas of Misiones Province, Argentina. A total of 12 rodent trapping sessions were conducted from April 2021 to February 2023 in Urugua-í and Cruce Caballero Provincial Parks. Orthohantavirus antibodies were detected in four A. montensis and three Oligoryzomys nigripes from both Provincial Parks. Molecular analyses provided evidence of the co-circulation of Jaborá and Juquitiba orthohantavirus genotypes. Both areas exhibited similar rodent community compositions, with A. montensis as the numerically dominant species and O. nigripes occurring at low abundance. In Urugua-í, A. montensis abundance varied in relation to precipitation and vegetation productivity, whereas no such associations were observed in Cruce Caballero. Further studies are needed to effectively monitor these communities and to gain a better understanding of potential fluctuations in seroprevalence, changes in genotype pathogenicity, and the possible detection of unknown genotypes.
This paper describes seasonal and annual Mid-Holocene (MH) temperature in South America simulated by PMIP2, PMIP3, and PMIP4 experiments and compares with information extracted from paleoclimate proxies. The study is focused on seasonal and annual MH anomalies with respect to the pre-Industrial (PI) climatology in PMIP2, PMIP3, and PMIP4 as well as MH anomalies with respect to the present-day (PD) climate in PMIP3 and PMIP4 (PD was not part of PMIP2 experiments). Results show that the three PMIP generation of models agree on colder MH in austral autumn and warmer MH in austral spring with respect to the PI which is a consequence of insolation changes. With the inclusion of modern warming produced by anthropogenic forcing, PMIP3 and PMIP4 agree on colder MH with respect to the PD except over broad areas in austral spring in which the reduction of temperature from MH to PI in response to insolation changes has not been reversed by human-induced warming yet. Comparisons of these model results against proxy-based reconstructions is challenging over most of South America due to three main reasons: (a) proxy information is scarce or absent over broad areas; (b) there are marked discrepancies among paleorecords extracted from nearby sites; and (c) estimated proxy uncertainties imply wide ranges of values of the reconstructed anomalies. Comparisons between paleorecords and model outputs over areas with unequivocal proxy-based signals of change show dissimilar results.
