scholarly journals Distribution of oligochaetes in a stream in the Atlantic Forest in southeastern Brazil

2015 ◽  
Vol 75 (1) ◽  
pp. 1-7 ◽  
Author(s):  
BFJV. Rosa ◽  
RT. Martins ◽  
RG. Alves
Keyword(s):  
Atlantic Forest ◽  
Indicator Species ◽  
Organic Matter Content ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Order Stream ◽  
Limnodrilus Hoffmeisteri ◽  
Species Analysis ◽  
Different Types ◽  
Fauna Composition

The oligochaetes are considered good indicators of ecological conditions and specific types of habitats. Among the factors that influence the distribution of these invertebrates are the water flow and the nature of the substrate. The aim of this study is to describe the composition and distribution of oligochaete species in a first-order stream in Atlantic Forest and try to identify if some species are associated with characteristics of particular types of habitats. In the dry season and in the rainy season, sand and litter samples in two riffle areas and two pool areas were collected in different parts along the stream using a hand net. The greatest observed richness and abundance occurred in sand in the pool, however the greatest estimated richness was obtained for litter in the pool. The Kruskal-Wallis analysis showed effect of the different types of habitat on the abundance and richness of oligochaetes. The Nonmetric Multidimensional Scaling (NMDS) and Multiresponse Permutation Procedure analysis (MRPP) indicated that the variation in the fauna composition had relation with different types of substrates. The indicator species analysis showed that Limnodrilus. hoffmeisteri was an indicator species in both the riffle sand and pool sand and Pristina americana was only an indicator in the pool sand. The high organic matter content in both sandy habitats probably favored the greater abundance of oligochaetes. The results showed that the substrate constitutes an important factor for the local distribution of these invertebrates in streams. The variation of the community structure among mesohabitats and the presence of indicator species of specific types of habitats in the stream demonstrate the importance of environmental heterogeneity for the oligochaetes fauna in forested streams.

scholarly journals Microbiological and faunal soil attributes of coffee cultivation under different management systems in Brazil

2015 ◽  
Vol 75 (4) ◽  
pp. 894-905 ◽  
Author(s):  
D. R. Lammel ◽  
L. C. B. Azevedo ◽  
A. M. Paula ◽  
R. D. Armas ◽  
D. Baretta ◽  
...  
Keyword(s):  
Mycorrhizal Fungi ◽  
Microbial Biomass Carbon ◽  
Integrated Management ◽  
Organic Matter Content ◽  
Arbuscular Mycorrhizal ◽  
Tropical Soils ◽  
Matter Content ◽  
Management Systems ◽  
Southeastern Brazil ◽  
Biological Parameters

Abstract Brazil is the biggest coffee producer in the world and different plantation management systems have been applied to improve sustainability and soil quality. Little is known about the environmental effects of these different management systems, therefore, the goal of this study was to use soil biological parameters as indicators of changes. Soils from plantations in Southeastern Brazil with conventional (CC), organic (OC) and integrated management systems containing intercropping of Brachiaria decumbens (IB) or Arachis pintoi (IA) were sampled. Total organic carbon (TOC), microbial biomass carbon (MBC) and nitrogen (MBN), microbial activity (C-CO2), metabolic quotient (qCO2), the enzymes dehydrogenase, urease, acid phosphatase and arylsulphatase, arbuscular mycorrhizal fungi (AMF) colonization and number of spores and soil fauna were evaluated. The greatest difference between the management systems was seen in soil organic matter content. The largest quantity of TOC was found in the OC, and the smallest was found in IA. TOC content influenced soil biological parameters. The use of all combined attributes was necessary to distinguish the four systems. Each management presented distinct faunal structure, and the data obtained with the trap method was more reliable than the TSBF (Tropical Soils) method. A canonic correlation analysis showed that Isopoda was correlated with TOC and the most abundant order with OC. Isoptera was the most abundant faunal order in IA and correlated with MBC. Overall, OC had higher values for most of the biological measurements and higher populations of Oligochaeta and Isopoda, corroborating with the concept that the OC is a more sustainable system.

scholarly journals Effect of Different Factors on the Adsorption of Phosphamidon on Two Different Types of Indian Soil

1998 ◽  
Vol 16 (8) ◽  
pp. 583-594 ◽  
Author(s):  
Dhirendra Singh
Keyword(s):  
Organic Matter ◽  
Adsorption Isotherms ◽  
Alluvial Soil ◽  
Organic Matter Content ◽  
Clay Content ◽  
Matter Content ◽  
Natural Soil ◽  
Standard Entropy ◽  
Indian Soil ◽  
Different Types

The effect of exchangeable cations (H+ and Na+). autoclaving, organic matter, anionic surfactants and temperature on the adsorption of phosphamidon on two different types of Indian soil was studied. The adsorption isotherms for all the effects/treatments were in close agreement with the Freundlich equation and yielded S-shaped isotherms. The amount of phosphamidon adsorbed in all cases was higher in medium black (silt loam) soil than alluvial soil (sandy loam) and was related to the organic matter content, clay content, CaCO3 content, surface area and cation-exchange capacity of the soils. The adsorption on both types of soil follows the order H+-soil > Na+-soil > natural soil at 10°C > natural soil at 20°C > autoclaved soil > organic matter-removed soil > anionic surfactant > natural soil at 40°C, which was in accordance with the Freundlich constant, KF, and distribution coefficient, Kd, values. The adsorption capacity of phosphamidon for organic matter and clay content for both the soils was evaluated by calculating the Kom and Kc values when it was found that phosphamidon adsorption was better correlated with the clay content than with the orgnic matter content on the basis of adsorption isotherms. Various thermodynamic parameters such as the thermodynamic equilibrium constant (K0), the standard free energy (ΔG0), the standard enthalpy (ΔH0) and the standard entropy (ΔS0) changes have been calculated as a means of predicting the nature of the isotherms.

scholarly journals Characteristics of Phosphorus Adsorption and Release in Different Types of Sediments

2020 ◽  
Vol 8 (05) ◽  
pp. 342-354
Author(s):  
Pengqiang Yang ◽  
Huanghe ◽  
Rujun Gao
Keyword(s):  
Heavy Metal ◽  
Particle Size ◽  
Organic Matter ◽  
Metal Ion ◽  
Organic Matter Content ◽  
Matter Content ◽  
Heavy Metal Ion ◽  
Phosphorus Adsorption ◽  
Different Types ◽  
Adsorption And Release

Taking different types of sediments as the research object, this research studied the adsorption and release characteristics of phosphorus under different conditions of different temperatures, coexisting heavy metal ion system, organic matter content and sediment particle size. Through used correlation analysis and principal component analysis, it discussed the influence of various factors on the adsorption and release of phosphorus in sediments. The results show that the adsorption of phosphorus by five different types of sediments from different sources reached saturation equilibrium in about 10 hours, and the increasing rates of 0 ℃, 15 ℃ and 30 ℃ are 17.5% ~ 23.7% and 18.2% ~ 38.3%, respectively.  The addition of coexisting heavy metal ion solution accelerated the adsorption of phosphorus in the sediment and reduced the total amount of phosphorus adsorption, that is, heavy metal ions inhibited the adsorption of phosphorus in the sediment; the presence of organic matter in the sediment would reduce its adsorption of phosphorus , Taihu farm and wetland sampling points have the largest sediment organic matter content. Compared with the other three points, the adsorption of phosphorus of these two  points accounted for 20.6% and 22.1%; the adsorption and release of phosphorus by sediment increased with the decrease of particle size. The maximum release rate was 5.216mg/kg-1·h-1. The result of principal component analysis shows that the order of influence on the adsorption and release of phosphorus by sediments is temperature> disturbance> organic matter content> heavy metal ion influence> particle size of sediments.

scholarly journals Variability of macrofauna distribution along a dissipative log-spiral sandy beach in Rio de Janeiro, Southeastern Brazil

2017 ◽  
Vol 81 (1) ◽  
pp. 111 ◽  
Author(s):  
Carlos A.M. Barboza ◽  
Tatiana Cabrini ◽  
Gustavo Mattos ◽  
Viviane Skinner ◽  
Ricardo Cardoso
Keyword(s):  
Grain Size ◽  
Organic Matter ◽  
Community Structure ◽  
Organic Matter Content ◽  
Principal Component ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Individual Species ◽  
Beach Slope ◽  
Sediment Sorting

Log-spiral beaches display defined physical gradients alongshore. However, the majority of studies focus on the variability of a single population of macrofauna species. We aimed to investigate the variation in species distribution and in community structure along ten transects on a log-spiral beach. Principal component analysis indicated a clear physical gradient alongshore. Redundancy analysis showed that the sheltered end was related to smaller particle sizes, higher organic matter content and high densities of polychaetes. The exposed end was characterized by coarser sand, lower organic matter content and a high presence of crustaceans. Model selection indicated that the “best fit” to explain the variability in the number of individuals included grain size and beach slope. Variability of the polychaete Scolelepis squamata was best explained by grain size, slope and sediment sorting. The best model for the cirolanid Excirolana armata only included sediment sorting. The physical gradient in sediment texture and the beach slope explained more than one-third of the variability in community structure. The physical variables were also correlated with the distribution of the individual species. We showed that the physical gradient on log-spiral coasts may be an important driver of macrofauna variability, even at mesoscales and in dissipative conditions.

scholarly journals Influence of environmental factors on the bathymetric distribution of the flecked box crab Hepatus pudibundus (Herbst, 1785) (Crustacea: Aethroidea) in the Southeastern Brazilian coast

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Veronica Pereira Bernardes ◽  
Fernando Luis Mantelatto ◽  
Thiago Elias da Silva ◽  
Aline Nonato de Sousa ◽  
Camila Hipólito Bernardo ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Food Availability ◽  
Organic Matter Content ◽  
Temporal Distribution ◽  
Predatory Behavior ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Brazilian Coast ◽  
Northern Coast ◽  
Spatio Temporal

Abstract: This study evaluated the relationships between environmental factors and the spatio-temporal distribution of H. pudibundus, with the hypothesis of differential occupation in coastal areas of southeastern Brazil. The samplings took place monthly in January-December 2000 period, along nine transects from 2 to 40 m of depth, in Ubatuba region, northern coast of São Paulo. We collected 1808 individuals of H. pudibundus. The highest abundance was recorded in winter in the transects 10-25 m deep. Abundance was positively correlated with organic matter content and texture sediment (phi values). With the retreat of the South Atlantic Central Water (SACW) in autumn and winter, the sediment swirls, suspending the detritivore and filter-feeding macrofauna, increasing the food availability. Sites characterized by finer sediment offer higher food availability, besides facilitating H. pudibundus burying behavior. Due to its opportunistic predatory behavior, this species feeds on a variety of organisms, including mollusks, annelids and foraminifera, which are preys more abundant in the studied area and in sediments of finer grain size.

scholarly journals Soil susceptibility to compaction under use conditions in southern Brazil

2017 ◽  
Vol 41 (1) ◽  
pp. 60-71 ◽  
Author(s):  
Michael Mazurana ◽  
Renato Levien ◽  
Alberto Vasconcellos Inda Junior ◽  
Osmar Conte ◽  
Luiz Antônio Bressani ◽  
...  
Keyword(s):  
Soil Type ◽  
Organic Matter Content ◽  
Matter Content ◽  
Soil Resistance ◽  
Mineralogical Characteristics ◽  
Compressibility Index ◽  
Different Types ◽  
Precompression Stress ◽  
Agricultural Use ◽  
The Impact

ABSTRACT The degree of soil compaction is intensified by its inadequate management, compaction being variable depending on soil type since even under identical management conditions, different types have different abilities to withstand load. The objective of this study was to evaluate the susceptibility to compaction of different classes of soils under no-tillage (NT) croping system compared to the original condition. Thus, i) soils with the same source material have distinct resistance to compression with increased NT adoption time; ii) the most sensitive indicators of this change are the ratios mass:volume and volume:volume and; iii) there is a relationship between resistance and compaction susceptibility with the amount and type of oxide. Soil samples were collected in areas under NT and under natural condition in order to assess the impact imposed by the NT on the attributes density and porosity, precompression stress and compressibility index and relate them to the oxide type of, and content in, the soils under study. The results show that the density and macroporosity were those most affected by the NT agricultural use, regardless of soil type, that is, its dynamic is related more to soil use and less to mineralogical characteristics. The soil resistance and compaction susceptibility were higher in soil developed in basalt, followed by those developed in sandstone and granite. Both the organic matter content and type and concentration of iron oxides were related to the soil resistance and susceptibility to compaction.

scholarly journals Community composition, beta diversity and structure of high altitude grasslands along an altitudinal gradient in southeastern Brazil

2020 ◽  
Vol 68 (3) ◽  
Author(s):  
Prímula Viana Campos ◽  
Pedro Manuel Villa ◽  
Carlos Ernesto Gonçalves Reynaud Schaefer ◽  
Jaquelina Alves Nunes ◽  
Stefan Porembski ◽  
...  
Keyword(s):  
Community Composition ◽  
Indicator Species ◽  
Beta Diversity ◽  
Altitudinal Gradient ◽  
Southeastern Brazil ◽  
Indicator Species Analysis ◽  
Composition And Structure ◽  
Species Analysis ◽  
Species Abundances ◽  
High Altitude Grasslands

Introduction: Studies on how the altitudinal gradient determines community composition and structure in tropical high altitude grasslands are limited. Objective: To evaluate the plant community composition and structure and their relationship with altitude and soil properties along an altitudinal gradient of three granitic rocky outcrops at the Serra do Brigadeiro State Park, Minas Gerais, in southeastern Brazil. Methods: In each selected site, 100 plots of 1 × 1 m were established, totalizing 300 plots in the study area. We compared floristic composition, relative coverage and abundance among sites. We performed beta diversity analysis. We also performed an indicator species analysis and a canonical correlation analysis to investigate possible relations between abiotic (soil and altitude) and biotic (indicator species abundances) variables. Results: We sampled a total of 9 276 individuals belonging to 39 families and 102 species. Significant differences were observed among sites regarding composition, abundance and coverage. The indicator species analysis revealed that 57 species (55.88 %) were indicators. The distribution of indicator species abundances was correlated with environmental variables. Conclusions: It was observed that altitude and soil play an important role in controlling community composition and structure, beta diversity and species distribution in the highland grasslands studied.

scholarly journals Abundance and spatial-temporal distribution of the shrimp Xiphopenaeus kroyeri (Decapoda: Penaeidae): an exploited species in southeast Brazil

2016 ◽  
Vol 76 (3) ◽  
pp. 764-773
Author(s):  
E. R. Silva ◽  
G. S. Sancinetti ◽  
A. Fransozo ◽  
A. Azevedo ◽  
R. C. Costa
Keyword(s):  
Species Abundance ◽  
Organic Matter Content ◽  
Coastal Region ◽  
Temporal Distribution ◽  
Mesh Size ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Otter Trawl ◽  
Xiphopenaeus Kroyeri

Abstract This study evaluated the abundance and spatial-temporal distribution of the shrimp Xiphopenaeus kroyeri in the coastal region of Macaé, state of Rio de Janeiro, southeastern Brazil. Monthly samples were obtained from March 2008 to February 2010 in six stations located in Inner (5, 10 and 15m depth) and Outer (25, 35 and 45m depth) areas. It was used a commercial fishery boat equipped with an otter-trawl net (3.5 m mouth width, mesh size 20mm and 15mm in the cod end). Water samples were taken for determination of temperature and salinity, and sediment samples for determination of texture and organic matter content. A total of 7146 shrimps were sampled. About 95% of all shrimps were caught in the shallow area, i.e., depths <20m. Greatest abundances were recorded in winter and spring. No significant correlation was observed between sediment (phi) and abundance. The distribution of X. kroyeri in the studied area was closely related to seasonal cold waterfront of the South Atlantic Central Water (SACW) and temperature was the main factor affecting the species abundance.

scholarly journals Effect of environmental factors on the abundance of decapod crustaceans from soft bottoms off southeastern Brazil

2013 ◽  
Vol 85 (4) ◽  
pp. 1345-1356 ◽  
Author(s):  
MICHELE FURLAN ◽  
ANTONIO L. CASTILHO ◽  
LISSANDRA C. FERNANDES-GOES ◽  
VIVIAN FRANSOZO ◽  
GIOVANA BERTINI ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Species Abundance ◽  
Organic Matter Content ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Brazilian Coast ◽  
Rocky Shores ◽  
Study Region ◽  
Factors Affecting ◽  
Fishing Boat

This study investigated the importance of variations in environmental factors affecting the abundance patterns of decapods on the southeastern Brazilian coast. Sampling was carried out monthly from January 1998 through December 1999 in Ubatumirim and Mar Virado, Ubatuba region, using a commercial shrimp fishing boat equipped with double-rig nets. Six areas adjacent to rocky shores were chosen. Bottom-water samples were collected using a Nansen bottle, to measure the temperature and salinity. Sediment samples were also obtained by means of a Van Veen grab, for determination of texture and organic-matter content. The association of environmental factors with species abundance was evaluated by Canonical Correspondence Analysis (α = 0.05). Forty-one species of Decapoda were used in the multivariate analysis. The analysis indicated that sediment texture (phi) and bottom temperature were the main factors correlated (p < 0.05) with the spatial and temporal abundance of the species. Considering the study region as faunal transition zone, including a mixture of species of both tropical and subantarctic origin, the species responded differently to environmental factors, mainly temperature. It is conceivable that the decapods adjust their distribution according to their intrinsic physiological limitations, possibly as a result of the available resources.

scholarly journals Selection of Indicator Species of the Tembotrione Sorption in Soils with Different Attributes

2018 ◽  
Vol 36 ◽  
Author(s):  
A.T. FARIA ◽  
E.M.G. SILVA ◽  
G.A.M. PEREIRA ◽  
M.F. SOUZA ◽  
A.A. SILVA ◽  
...  
Keyword(s):  
Soil Solution ◽  
Plant Species ◽  
Indicator Species ◽  
Organic Matter Content ◽  
High Sensitivity ◽  
Soil Classification ◽  
Tropical Soils ◽  
Matter Content ◽  
Initial Growth ◽  
Low Concentrations

ABSTRACT: Studies on herbicide behavior in soils may be performed using biological and chemical methods. The efficiency of the biological method depends on the indicator species sensitivity to low herbicide concentrations in the soil solution. Among the herbicides commonly used in Brazil for corn cultivation, tembotrione stands out. In the last agricultural seasons, the intoxication of some crops when cultivated in succession to corn has been reported, which may be attributed to tembotrione recommendations without the knowledge of their interactions with colloids of tropical soils. In this research, we selected an indicator plant species of tembotrione residues in the soil after sorting 12 species. The sorption of this herbicide was estimated in two Oxisols (Latossolo Amarelo and Latossolo Vermelho-Amarelo, Brazilian Soil Classification) and in a Histosol (Organossolo, Brazilian Soil Classification) with different attributes. Initially, after sorting the 12 plant species, the two most efficient in detecting tembotrione in the soil were selected. In the second stage, the most sensitive species was selected. In the third stage, tembotrione sorption was assessed in the three soils by using the selected species. Among the 12 species, Beta vulgaris and Brassica oleracea var. capitata were the most efficient in detecting tembotrione at low concentrations in the soil, being B. vulgaris (beet) the most sensitive. Thus, due to its ease of cultivation, high sensitivity, and fast initial growth, beet can be used as an indicator species of tembotrione presence in the soil solution. The sorption of this herbicide was higher in the Histosol and it is directly related to the organic matter content.

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