Cristiane Figueira da Silva

Carbono orgânico total, biomassa microbiana e atividade enzimática do solo de áreas agrícolas, florestais e pastagem no médio Vale do Paraíba do Sul (RJ)

Soil characteristics such as total organic carbon (TOC), microbial biomass and enzymatic activity are influenced by many factors and have been suggested as suitable indicators of changes caused by different land use systems and soil management. The objective of this study was to evaluate the COT, microbial biomass and enzymatic activity of a typical Inceptisol in agricultural, forest and grassland areas in the Middle Valley of the Paraiba do Sul river (RJ). The systems evaluated were: annual agriculture (Agan); perennial agriculture (PAg), pasture, early secondary forest (SFEA) intermediate secondary forest (SFSM) in advanced succession stage (SFEA). Soil samples were collected from the 0-5 cm layer in two different seasons (dry and rainy) to determine the total organic carbon (TOC) and biological properties (microbial biomass - CBM; microbial biomass N- NBM; basal respiration - RB; metabolic quotient - qCO2; microbial quotient - qMIC, and activity of the enzymes arylsulfatase, β-glucosidase and acid phosphatase). The soil of the agricultural areas showed a reduction in the TOC and biological properties (enzyme activity and carbon and microbial biomass nitrogen) compared to pasture and forest. The principal component analysis distinguished the agricultural systems from the forest and pasture systems. It was observed that in both periods, the SFSM and pasture were associated with the COT and most biological factors, as opposed to the agricultural systems.

Influência do sistema de plantio sobre atributos dendrométricos e fauna edáfica, em área degradada pela extração de argila

The intercropping of Eucalyptus with legumes can promote an improvement of soil biological quality in degraded areas and also be advantageous for the species of the consortium. The aim of this study was to evaluate the influence of planting systems (monoculture and consortium) of Acacia mangium (AM), Sesbania virgata (SV) and Eucalyptus camaldulensis (EC) on the biological characteristics of the plants (dendrometric attributes) and specifically on the fauna in the litter and the surface soil layer (0-0.05 m). An experiment in a randomized block was conducted with six treatments and three replications. The treatments used to evaluate the dendrometric attributes were: 100 % EC and 100 % AM; 50 % EC + 50 % AM; 50 % EC + 50 % SV; 50 % AM + 50 % SV). To evaluate the soil fauna, biological characteristics were assessed in treatments with: 100 % EC; 100 % AM; 100 % SV; 50 % EC:50 % SV; and 50 % AM:50 % SV. Forty-eight months after planting, the height (H) and diameter at breast height (DBH) of the species EC and AM were measured, and estimates of basal area (BA) and wood volume with bark per tree (WBT). The abundance and diversity of the soil fauna were evaluated in leaf litter and soil (0.0-0.05 m). When intercropped with legumes, the DBH, BA and WBT of EC were higher. In contrast, for AM these variables were unaltered when intercropped with EC and SV. Plantations of EC-SV consortium promoted higher total abundance of organisms and highest values of Shannon diversity and evenness indices, especially with regard to the litter compartment.

Fungos micorrízicos arbusculares e proteína do solo relacionada à glomalina em área degradada por extração de argila e revegetada com eucalipto e acácia

The objective of this study was to evaluate the influence of revegetation with Eucalyptus camaldulensis and Acacia mangium in pure and mixed stands in the composition and mycorrhizal fungi diversity (AMF), as well as in the production of glomalin-related soil protein (GRSP) of an area degraded by clay extraction. The experimental design used was randomized complete block with four treatments (pure stands Eucalyptus camaldulensis and Acacia mangium; mixed Eucalyptus camaldulensis + Acacia mangium; and covered with spontaneous vegetation – ADVE) and three replications. Soil samples were collected at 0-5 cm soil layer in each plot. The spores were extracted and taxonomically identified. Relative density, frequency of each species and the Shannon-Wiener, Pielou and Simpson indexes were analyzed. The GRSP (total glomalin – TG and easily extractable glomalin - EEG) was extracted with sodium citrate and quantified by the Bradford method. Abundance of AMF was higher in the degraded areas covered by weeds (spontaneous vegetation) compared to plantations; however, it showed lower species diversity. The areas of eucalypt monoculture showed a lower level of AMF diversity in relation to areas of eucalypt intercropped with Acacia. The genera Glomus and Acaulospora were the AMF, with the largest number of species. The GRSP was closely correlated with soil C and N, which observed in greater amounts in plantations in relation to the sites covered with spontaneous vegetation. Revegetation of clay extraction site promoted the reduction of AMF sporulation, while the diversity and amount GRSP increased.

Fungos Micorrízicos Arbusculares em Dois Fragmentos Florestais de Restinga Periodicamente Inundável em Marambaia, RJ

O presente estudo objetivou avaliar a ocorrencia de fungos micorrizicos arbusculares (FMA) em dois fragmentos florestais (FF 1 e FF 2) de Restinga periodicamente inundavel, dispostos em um gradiente de saturacao hidrica do solo em Marambaia, RJ. Em cada area foram coletadas amostras da camada superficial (0-5 cm), para avaliacao da comunidade de FMA e dos atributos do solo. Entre as seis especies de FMA encontradas, cinco foram comuns a ambas as areas eAcaulospora scrobiculata se restringiu a FF 1.Acaulospora e Glomus foram os generos mais adaptados as condicoes ambientais dos ecossistemas. Nao houve diferenca significativa entre os fragmentos quanto a riqueza de especies de FMA. Contudo, a abundância de esporos foi maior no FF 1. Parte destes resultados pode ser um reflexo dos menores valores de P disponivel, teor de agua e temperatura do solo no FF 1, quando comparado ao FF 2.

COMUNIDADE DE FUNGOS MICORRÍZICOS ARBUSCULARES: DIVERSIDADE, COMPOSIÇÃO E GLOMALINA EM ÁREA REVEGETADA COM SESBÂNIA

The community composition and diversity of arbuscular mycorrhizal fungi (AMF) can be affected by several factors, including the climate, soil biota and host plants. This study aimed to evaluate the influence of Sesbania virgata (SV) revegetation in pure and intercropped with plantation Eucalyptus camaldulensis (EC) and Acacia mangium (AM), in the composition and diversity of arbuscular mycorrhizal fungi (AMF), and the amount glomalin-related soil protein (GRSP) in an area damaged by clay extraction. The experimental design was a randomized block with four treatments (planting pure SV - 100SV); consortium of SV + EC - 50SV: 50EC; consortium AM SV + - 50SV: 50AM) and degraded area with natural vegetation - ADVE) and three replications. Revegetation of mining digging clay with SV in pure or intercropped planting reduced the abundance of spores and increased species diversity of arbuscular mycorrhizal fungi. Furthermore, increased the amount of glomalin-related soil protein compared with the degraded area and spontaneous vegetation.

Incidence and diversity of arbuscular mycorrhizal fungi and successor herbaceous plants in an agro-system irrigated with produced water

The purpose of this study was to evaluate the diversity of herbaceous plants and arbuscular mycorrhizal fungi following the cultivation of sunflower (Helianthus annuus L., cv. BRS 321) irrigated with produced water. The sunflower plants were irrigated during three successive cycles with different types of water: produced water obtained through simple filtration (PWSF), and secondly, produced water treated by reverse osmosis (PWRO), and the control with groundwater from the aquifer Açu (WCA). In June 2014, five months after the final harvest, the treatments were evaluated in terms of the diversity of successor plants and their roots colonized by arbuscular mycorrhiza (AM); and samples of soil, in which the following were measured: the spore abundance of AM fungi, the levels of glomalin in easily extracted glomalin and total glomalin. Of a total of eighteen species of herbaceous plants which were identified in the experimental field, Dactyloctenium aegyptium was related with the use of PWSF, Panicum sp. and Diodella apiculata with the use of PWRO, and Trianthema portulacastrum and Eragrostis tenella with the control WCA. The diversity of AM fungi was affected by irrigation with PWSF, in which two species of Acaulospora, one species of Gigaspora and species of Paraglomus were absent, compared to the treatment with PWRO. Acaulospora sp.1 was related with the WCA control as an indicator species. The use of produced water which had undergone reverse osmosis had a short-term effect on the content of glomalin which is easily extractable from the soil but did not change the mycorrhization rates of plants. These results enable us to infer that irrigation with produced water leads to a reduction in the diversity of herbaceous plants and of arbuscular mycorrhizal fungi in the soil, confirming the importance of monitoring agro-systems irrigated with residual water.

Effects of Natural Atlantic Forest Regeneration on Soil Fauna, Brazil

The stage of natural forest regeneration may influence soil fauna. This study aimed to test the hypothesis that there are differences in the structure and composition of the soil fauna communities between areas undergoing less advanced (LAS) and more advanced (MAS) stages of natural regeneration of Seasonal Semideciduous Forest at Pinheiral, RJ. Soil fauna was sampled using pitfall traps, during dry and rainy seasons. Total abundance, abundance of the saprophagous/predator group, mainly Formicidae, and the relative participation of Orthoptera were higher in MAS, while the relative participation of Acari, Araneae, Coleoptera, Diptera and the herbivorous group were higher in LAS, during both climatic seasons. Some taxonomic groups were restricted to one of the areas. Richness, evenness and diversity tended to present higher values in LAS (dry season). The higher complexity of the soil fauna community was correlated to the higher leaf litter standing stock in LAS.

Epigeal Fauna and Soil Chemical Attributes in Grazing and Regeneration Areas

ABSTRACT The objective of this study was to evaluate the influence of natural pasture and spontaneous regeneration on soil chemical properties and epigeal fauna community using a secondary Atlantic Forest as reference. The study areas were located in Passa Vinte, Minas Gerais, Brazil. In each study area, pitfall traps were used to sample epigeal fauna in the dry and rainy seasons. Earth samples were collected at a depth of 0-5 cm in the dry and rainy seasons for analysis of chemical attributes. The pasture and regeneration areas showed an overall activity of epigeal fauna and functional groups similar to the forest area. However, the diversity evaluated by the Shannon and Pielou evenness indices and the total richness were lower than the observed in the forest. The best fertility attributes were observed in the forest and pasture areas. Keywords: land use, diversity, forest fragments. 1. INTRODUCTION The Atlantic Forest is the most fragmented Brazilian biome and the second largest tropical rainforest in the Americas. It originally spread throughout an uninterrupted strip across the Brazilian coast (Fundacao SOS Mata Atlântica, 2001). Although the Atlantic Forest is one of the hotspots on the planet in terms of biological diversity, it is also one of the most threatened biomes (Brasil, 2015 ). Because of anthropogenic interference (deforestation), most forest remnants in this biome are small, highly disturbed, isolated, little known, little protected ( Menezes et al., 2009 ), and often surrounded by agricultural crops and pastures and regenerating forests.Deforestation for agricultural purposes followed by pasture and/or spontaneous regeneration may generate a landscape with different levels of ecological degradation/restoration. The spontaneous regeneration is an essential process for restoration of degraded areas, since it promotes the addition of new individuals. The mechanisms involved in this process (seed falls, soil seed bank formation and seedling and young plant banks) increase the density and richness of species in the community and contribute to ecological succession and its biological diversity. Spontaneous regeneration can make ecological interrelations stronger and contribute to the restoration of the system, and also to its increase in complexity and consequent self-sustainability (Quintela, 2005), which is essential in the case of the Atlantic Forest.Chemical, physical and biological soil attributes are among the main indicators for evaluating environmental restoration and degradation processes ( Silva et al., 2012a ;

DEPOSIÇÃO DE SERAPILHEIRA E CARBONO EM PLANTIOS DE SABIÁ, ANDIROBA E FLORESTA SECUNDÁRIA

O objetivo do estudo foi avaliar o padrao de deposicao anual de serapilheira, carbono orgânico (CO) e nitrogenio (N) entre as areas de floresta secundaria (FS) e plantios de sabia ( Mimosa caesalpinaefolia Benth.) e andiroba ( Carapa guianenses Aubl.) (ambos os plantios com regeneracao natural) na Floresta Nacional Mario Xavier, no municipio de Seropedica (RJ). Para a avaliacao anual de deposicao da serapilheira foram usados coletores circulares durante um ano (de outubro de 2006 a setembro de 2007). Os valores de aporte total de serapilheira foram 8,82, 8,35 e 6,95 Mg ha -1 ano -1 para as areas de plantio de M. caesalpinaeolia , plantio de C. guianenses e floresta secundaria, respectivamente. O verao foi a unica estacao onde nao foram observadas diferencas significativas nos aportes de serapilheira entre as areas. As fracoes folha e fruto, em media, foram as que contribuiram com maior e menor aporte de material deciduo, respectivamente, nas tres areas avaliadas. Observou-se que as areas de plantios de M. caesalpinaefolia e C. guianenses contribuiram com fluxo de CO e N para o solo via serapilheira semelhante a FS. Correlacoes entre as taxas de deposicao serapilheira e as variaveis climaticas foram observadas apenas nas areas de floresta secundaria (correlacao negativa com a temperatura e precipitacao) e M. caesalpinaefolia (correlacao negativa com a precipitacao).

PRODUCTION OF AUSTRALIAN CEDAR SEEDLINGS INOCULATED WITH ARBUSCULAR MYCORRHIZAL FUNGI IN DIFFERENT TYPES OF CONTAINERS

The present study aimed to evaluate the growth and the levels of N, P, K, Ca and Mg in Australian cedar seedlings which had been inoculated with arbuscular mycorrhizal fungi (AMF) in different types of containers. The experiment was carried out in a greenhouse and the experimental design was that of randomized complete blocks (RCB), with a 4 x 4 factorial design consisting of four inoculation treatments with AMF (Rhizophagus clarum, Gigaspora margarita, a mixed inoculation (R. clarum + G. margarita) and the control (with no AMF inoculation); four types of containers (plastic bags measuring 250 cm3, tubes of 55 and 130 cm3 and pressed blocks 440 cm3. plant-1), with four repetitions. The height, the diameter of the stem base, the aerial part dry weight (APDW), the dry weight of the root (DWR) and the total plant dry weight (DW) were measured, along with the Dickson quality index, the percentage of mycorrhizal colonization and the levels of N, P, K, Ca and Mg in the aerial part dry weight. One hundred and thirty eight days (138) days after sowing, the greatest growth and/or the highest levels of P, K and Ca could be observed in the aerial part dry weight of the Australian cedar seedlings which had been planted in the pressed block container and inoculated with a mixture of the two AMF species (G. margarita + R. clarum) or with just R. clarum. Thus it can be seen that AMF can make a significant contribution to the production of Australian cedar seedlings.