ABSTRACT A first large-scale systematic survey of natural radioactivity contents of soils of the state of Rio de Janeiro is presented, focused on the establishment of Quality Reference Values (QRVs). Undisturbed soil samples were collected from 243 areas and analyzed by gamma spectrometry. The activity contents varied largely, ranging from 12.2 to 1,029 Bq kg−1 for 40K (geometric mean of 111.1 Bq kg−1), from 3.5 to 99.8 Bq kg−1 for 226Ra (geometric mean of 29.7 Bq kg−1), and from 5.4 […]

ABSTRACT Microorganisms are excellent soil quality indicators because their properties within the soil community change quickly in response to changes in the surrounding environment. The aim of this study was to determine if the structure and diversity of soil bacterial and fungal communities were useful for discriminating cut flower cultures under conventional (CM), ecological (EM), and intermediate (IM) management practices. Results obtained by PCR-DGGE revealed that bacteria had lower similarity in structure and higher diversity under EM than under CM. […]

ABSTRACT The CO2 emission from the soil surface, commonly referred to as soil CO2 efflux (ECO2) or soil respiration, is the sum of processes that include root respiration and microbial activity. Measuring this evolution is important to establish sustainable land use models and to estimate global fluxes of carbon, which affect climate change. Despite its importance, few measurements have been made in areas of the semiarid Brazilian Northeast region, and most of them were made using the alkali absorption method […]

ABSTRACT: The pattern of variation in soil and landform properties in relation to environmental covariates are closely related to soil type distribution. The aim of this study was to apply digital soil mapping techniques to analysis of the pattern of soil property variation in relation to environmental covariates under periglacial conditions at Keller Peninsula, Maritime Antarctica. We considered the hypothesis that covariates normally used for environmental correlation elsewhere can be adequately employed in periglacial areas in Maritime Antarctica. For that […]

ABSTRACT: High yields obtained from soybean [Glycine max (L.) Merrill], and consequent profits, are related to efficient symbiosis of soybean with nitrogen fixing bacteria of the Bradyrhizobium genus. Inoculation with strains belonging to the Bradyrhizobium japonicum, B. elkanii, and B. diazofficiens species, approved by the Brazilian Ministry of Agriculture (MAPA), is a common practice for this crop. However, variations in the composition of inoculants can change the quality of the product. The aim of this study was to genetically identify […]

ABSTRACT: The evaluation of soils in representative landscapes constitutes an opportunity to evaluate spatial distribution, discuss formation processes, and apply this knowledge to land use and management. In this sense, from the perspective of an environmentally diversified region, the aim of the present study is to evaluate the occurrence and understand the formation of soils in different geomorphic surfaces of a landscape from a mountain region in the state of Rio de Janeiro. The study was developed in the Pito […]

ABSTRACT Phosphorus (P) fractionation is a suitable procedure to ascertain P lability in sediments and is able to distinguish sources of P under different soil management practices in a catchment. Brazil is the second largest producer and the largest exporter of tobacco in the world. Inadequate management of cultivated areas exposes the soil to erosion processes, accelerating the transfer of sediment and P to water bodies, which leads to eutrophication. We evaluated the P forms in suspended sediments collected at […]

ABSTRACT The identification of areas with greater erosive potential is important for planning soil and water conservation. The objective of this study was to evaluate the physical characteristics of rainfall events in the state of Rio de Janeiro, Brazil, and their interactions with rainfall patterns through multivariate statistical analysis. Rainfall depth, kinetic energy, 30-min intensity (I30), duration of rainfall events, and the erosivity indices KE >10, KE >25, and EI30 in 36 locations (stations) were subjected to principal component analysis […]

ABSTRACT For the development of nutrient budget models to recommend lime and fertilizers for agricultural and forestry crops, curves of plant growth and nutrient accumulation are required. Information about how nutrients are partitioned between the different plant organs is also necessary, but still scarce for pine in Brazil. This study evaluated the growth, biomass partitioning, and nutrient dynamics in pine forests in southern Brazil. To this end, we assessed unthinned 2, 4, 6, and 8-year-old stands of Pinus taeda L. […]

Abstract Under the background of climate change, the increase of atmospheric CO2 and drought frequency have been considered as significant influencers on the soil microbial communities and the yield and quality of crop. In this study, impacts of increased ambient CO2 and drought on soil microbial structure and functional diversity of a Stagnic Anthrosol were investigated in phytotron growth chambers, by testing two representative CO2 levels, three soil moisture levels, and two soil cover types (with or without Glycine max). […]