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Turfeiras da Serra do Espinha?o Meridional - MG: I - caracteriza??o e classifica??o
Silva, Alexandre Christófaro;Horák, Ingrid;Cortizas, Antonio Martinez;Vidal-Torrado, Pablo;Racedo, Jose Rodrigues;Grazziotti, Paulo Henrique;Silva, Enilson de Barros;Ferreira, Celmo Aparecido;
Revista Brasileira de Ciência do Solo , 2009, DOI: 10.1590/S0100-06832009000500030
Abstract: peat bogs are a special environment for studies related with the dynamics of organic matter, landscape evolution and climatic changes and with local, regional and global cycles of atmospheric pollution. peat bogs contribute to the global c sequestration, act as water reservoirs and are the habitat of an endemic biodiversity. the serra do espinha?o meridional (minas gerais state, brazil) - sdem - a terrestrial biosphere reservation area, contains a considerably large area with different types of peat bogs, which were described in three profiles at 1,250, 1,800 and 1,350 m above sea level and classified, respectively, as organosol haplic sapric terric (p1), organosol haplic fibric typical (p2) and organosol haplic hemic typical (p4), in agreement with the brazilian system of soil classification. the three profiles were characterized morphologically and the samples were chemically, physically and microbiologically analyzed. it was found that the location, altitude and drainage influenced the morphologic, physical, chemical, and biological properties of the peat bogs in sdem. the decomposition state of organic matter is more advanced when the drainage in the peat bogs is better. the amount of heavy metals is related with the quantity and granulometric composition of the mineral fraction and location of the peat bogs. the highest mean levels of ti, zr, pb were detected in profile p1, highest mean levels of mn, zn and cu in p2, and the highest mean fe content in p4. the intensity of microbiological activity in the peat bogs p2 and p4 was related with the drainage and heavy-metal content of its layers.
A influência litológica nas taxas de denuda??o geoquímica do médio Espinha?o Meridional - MG
Rezende, éric Andrade;Le?o, Marina Ribeiro;Salgado, André Augusto Rodrigues;Oliveira, Carmélia Kerolly Ramos de;Nalini Junior, Herminio Arias;
Sociedade & Natureza , 2010, DOI: 10.1590/S1982-45132010000300007
Abstract: this paper investigates the relationship between lithology and geochemical denudation rates in the middle serra do espinha?o meridional. denudation rates represent the volume of material from the alteration of rocks taken from a specified area at a known time period (souch, 2004). these rates are strongly controlled by geological substrate, especially in less extensive watersheds. the method adopted is based on sampling of surface waters of sixteen sub-basins - that have low human interference and drain predominantly quartzite - and measuring the sampled channels flow. chemical analysis of surface water collected in the humid and dry periods of the year were used to calculate geochemical denudation, which generally showed low in spite of the predominant rock resistance to weathering and denudational processes. the results showed that despite the relatively homogeneous lithology, the area does not hide the finding of a differential geochemical denudation, where: (i) basins that drain carbonate rocks have higher denudation rates, confirming the high solubility of this material, (ii) basins draining quartzite units show low denudation rates, especially the ones over the formations of galho do miguel and sopa-brumadinho.
A influência litológica nas taxas de denuda o geoquímica do médio Espinha o Meridional – MG / Lithological influence on rates of geochemical denudation in the middle Espinha o Meridional – MG  [cached]
éric Andrade Rezende, , , ,,Marina Ribeiro Le?o,André Augusto Rodrigues Salgado,Carmélia Kerolly Ramos de Oliveira
Revista Sociedade & Natureza , 2010,
Abstract: O presente trabalho visa investigar a influência da litologia nas atuais taxas de denuda o geoquímica na média Serra do Espinha o Meridional. As taxas de denuda o correspondem ao volume de material proveniente da altera o das rochas retirado de uma determinada área em um dado período de tempo (Souch, 2004). Estas taxas s o intensamente controladas pelo substrato geológico, notadamente em bacias hidrográficas de menor extens o. O método adotado baseia-se na coleta de amostras das águas superficiais de dezesseis sub-bacias hidrográficas – que apresentam baixa interferência antrópica e est o sobre substrato geológico predominantemente quartzítico – e na medi o da vaz o dos canais amostrados. Análises químicas de águas superficiais, coletadas nos períodos úmido e seco do ano, foram utilizadas no cálculo da taxa de denuda o geoquímica, que, de modo geral, apresentou-se baixa devido a alta resistência dos quartzitos - litologia predominante. Os resultados demonstraram que, apesar da relativa homogeneidade litológica, a área apresenta uma denuda o geoquímica diferencial, onde: (i) bacias que drenam rochas carbonáticas possuem taxas mais elevadas de denuda o, confirmando a alta solubilidade desse material, (ii) bacias que drenam unidades quartzíticas apresentam taxas baixas de denuda o, principalmente aquelas sobre as forma es Galho do Miguel e Sopa-Brumadinho.
Compara??o de métodos para estimar a acidez potencial mediante determina??o do pH SMP em Organossolos da Serra do Espinha?o Meridional
Silva, Enilson de Barros;Silva, Alexandre Christófaro;Grazziotti, Paulo Henrique;Farnezi, Múcio Magno de Melo;Ferreira, Celmo Aparecido;Costa, Hesmael Antonio Orlandi;Horak, Ingrid;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000500022
Abstract: in spite of the agricultural use potential and the peculiar edaphic characteristics, few studies have been conducted to estimate the potential acidity of soils with high organic matter content. the objective of this study was to establish a mathematical model that could estimate the potential acidity (h + al) based on the ph smp after determination of the soil ph in water and in cacl2 10 mmol l-1 solution with reading of the ph in the suspension or supernatant of the equilibrium solution smp in a certain soil: smp buffer ratio for organosols from the of serra do espinha?o meridional (sdem) region (between 17 ° 30 ' and 20 ° 30 ' s, and 43 ° and 44 ° w) in minas gerais state, brazil. twenty-two organosol samples from the sdem were used. the soils are classified as terric organosol haplic sapric, typical organosol haplic fibric and typical organosol haplic hemic. the potential acidity of organosols from sdem can be estimated satisfactorily based on the ph smp at a soil: smp buffer ratio of 10:10 measured in the soil- smp solution used in the routine soil water ph determination. of the chemical attributes organic carbon was the one that most influenced the potential acidity of organosol in sdem.
Turfeiras da Serra do Espinha?o Meridional - MG: II - influência da drenagem na composi??o elementar e substancias húmicas
Silva, Alexandre Christófaro;Horák, Ingrid;Vidal-Torrado, Pablo;Cortizas, Antonio Martinez;Racedo, Jose Rodrigues;Campos, José Ricardo da Rocha;
Revista Brasileira de Ciência do Solo , 2009, DOI: 10.1590/S0100-06832009000500031
Abstract: peat bogs are organosols formed under ideal ecological conditions in terms of the accumulation of organic material, controlled by geomorphological and geological processes and climate. the physical, chemistry and biological constitution of peat bogs is largely unknown. in this study the peat bogs of the southern serra do espinha?o (minas gerais, brazil) were described and sampled from three profiles at 1,250 m (p1), 1,350 m (p4) and 1,800 m (p2) above sea level. the three profiles were characterized morphologically, the collected samples were chemically analyzed and the organic matter was fractioned in humin, fulvic and humic acids. the organic matter of the peat bog profiles differed strikingly in chemical composition and contents of humic substances and in the chemical composition of humic acids. the variations in drainage conditions were mostly responsible for the qualitative and quantitative differentiation of organic matter. in peat bog p1, with moderate drainage, the c/n and o/c ratios of the organic matter were higher, fulvic acid predominant among the humic substances and humic acids had a higher c/n ratio. in the peat bog p2 and p4, with very poor drainage, c/n and o/c ratios were lower in the organic matter, humin largely predominant among humic substances and c/n ratios in humic acids were lowest.
Estimating soil plasticity properties from pedological data  [cached]
G C Fanourakis
Journal of the South African Institution of Civil Engineering , 2012,
Abstract: A number of pedological soil classification systems have been developed worldwide. These include an internationally accepted system and various national systems, some of which have been incorporated into databases which include maps. Such information is used primarily for agricultural purposes. Various physical and chemical soil properties are used for classifying soils according to these pedological systems. This paper proposes an approach, based on a research project, which may be used to statistically significantly determine the plasticity characteristics of soils from the physical and chemical properties that are used to pedologically classify soils by systems, such as the South African Binomial System. These plasticity characteristics may be used to establish the engineering soil classification groups which may, in turn, be used as a means of rapidly determining the general suitability of areas for proposed developments, particularly during the preliminary stages of transportation route locations and township developments, with a resultant saving of time and money.
Morphology of peatland lakes
Krzysztof Bana
Limnological Review , 2010, DOI: 10.2478/v10194-011-0001-9
Abstract: The morphometric features of 10 small (0.1-2.9 ha) and shallow (4-16 m) peatland lakes, located in basins filled with peat, were examined. The elongation of such lakes and the development coefficient of their shorelines are very low. The mean depth is close to the maximum value (7.0±4.8 and 7.8±3.9 m, respectively), as the lake bottom is normally flat and the basin walls are often vertical. In terms of morphometric features, the peatland lakes were divided into large (1.92±1.12 ha) and small (0.33±0.33 ha). The former are surrounded by a relatively narrow belt of peatlands and characterized by low values of Ohle coefficient and Schindler factor (1.81±2.04 and 0.32±0.13), which makes them very susceptible to the effect of peatlands. The smallest lakes are located in the central part of big peatlands. Their values of Ohle coefficient and Schindler factor are five times higher, whereas their volume is ten times less (13 750 m3 as compared to 125 000 m3; p<0.001). The bottom slope angle is considerable. In peatland lakes, there is little space that could be occupied by vegetation. In deep moraine-dammed lakes plants occur only on vertical walls, whereas in shallow water bodies, plants also thrive on the bottom.
Polygonaceae da cadeia do espinha?o, Brasil
Melo, Efigênia de;
Acta Botanica Brasilica , 2000, DOI: 10.1590/S0102-33062000000300006
Abstract: the study of the family polygonaceae is a part of the project "study of the flora and fauna of the espinha?o range region, bahia, brazil". in this paper we are including the species of the espinha?o range of minas gerais state. in that area the family is represented by the following genera, with respective number of species: coccoloba (14): c. acrostichoides, c. alagoensis, c. alnifolia, c. brasiliensis, c. cereifera, c. fastigiata, c. lucidula, c. ochreolata, c. pipericarpa, c. salicifolia, c. scandens, c. schwackeana, c. striata and c. warmingii, polygonum (6): p. acuminatum, p. ferrugineum, p. hispidum, p. hydropiperoides, p. meisnerianum and p. punctatum, rumex (1): r. crispus, ruprechtia (1): r. apetala and triplaris (1): t. gardneriana. key to the genera and species, descriptions and illustrations, as well as comments on the geographic distribution, phenology and variability of the species are presented.
The distribution of peatland in Europe
L. Montanarella,R.J.A. Jones,R. Hiederer
Mires and Peat , 2006,
Abstract: This paper derives the distribution of peatland in Europe as the extent of peat and peat-topped soils indicated by soil databases. The data sources were the 1:1,000,000 European Soil Database (v1.0) and a data set of organic carbon content (%) for the topsoils of Europe at 1km x 1km resolution that was recently published in map form. The strong influences of vegetation and land use on soil organic carbon (OC) content were taken into account in computing the 1km (OC) data set, as was the influence of temperature. The areas of peat and peat-topped soils estimated from the European Soil Database are generally in close agreement with those obtained using the Map of OC in Topsoils of Europe. The results reveal a strong northern bias in the distribution of organic soils across Europe. Almost one-third of the European peatland resource is in Finland, and more than a quarter is in Sweden. The remainder is in Poland, the UK, Norway, Germany, Ireland, Estonia, Latvia, The Netherlands and France. Small areas of peat and peat-topped soils also occur in Lithuania, Hungary, Denmark and the Czech Republic. For most European countries, the distribution of peat and peat-topped soils is probably more accurately portrayed by the Map of OC in Topsoils of Europe than by the European Soil Map and Database. Such baseline data are important for the conservation of peat and for making much more precise estimates of carbon stocks in topsoil than have been possible hitherto. The results are also relevant to the planning of effective soil protection measures at European level.
Polygonaceae da cadeia do espinha o, Brasil  [cached]
Melo Efigênia de
Acta Botanica Brasilica , 2000,
Abstract: O estudo da família Polygonaceae é parte do projeto "Estudos de flora e fauna na Cadeia do Espinha o, Bahia, Brasil". Neste trabalho a área de estudo foi ampliada, abrangendo também as espécies da Cadeia do Espinha o do Estado de Minas Gerais. A família está representada na área por cinco gêneros, com os respectivos números de espécies: Coccoloba (14): C. acrostichoides, C. alagoensis, C. alnifolia, C. brasiliensis, C. cereifera, C. fastigiata, C. lucidula, C. ochreolata, C. pipericarpa, C. salicifolia, C. scandens, C. schwackeana, C. striata e C. warmingii, Polygonum (6): P. acuminatum, P. ferrugineum, P. hispidum, P. hydropiperoides, P. meisnerianum e P. punctatum, Rumex (1): R. crispus, Ruprechtia (1): R. apetala e Triplaris (1): T. gardneriana. S o apresentadas chaves para os gêneros e espécies, bem como descri es, ilustra es, comentários sobre a distribui o geográfica, fenologia e variabilidade para todos os táxons.
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