Márcio Rocha Francelino

Digital soilscape mapping of tropical hillslope areas by neural networks

Geomorphometric variables are applied in digital soil mapping because of their strong correlation with the disposition and distribution of pedological components of the landscapes. In this research, the relationship between environmental components of tropical hillslope areas in the Rio de Janeiro State, Brazil, artificial neural networks (ANN), and maximum likelihood algorithm (MaxLike) were evaluated with the aid of geoprocessing techniques. ANN and MaxLike were applied to soilscape mapping and the results were compared to the original map. The ANN architectures with seven and five neurons in the hidden layer produced the best classifications when using samples obtained systematically. When random samples were applied, the best neural net architectures were within 22 and 16 neurons in the hidden layer. In conclusion, the ANN can contribute to soilscape surveys, making map delineation faster and less expensive. The digital elevation model (DEM) and its derived attributes can contribute to the understanding of the soil-landscape relationship of tropical hillslope areas; the use of artificial neural networks and MaxLike is feasible for digital soilscape mapping. The systematic sampling method provided a global accuracy of 70 % and 65.9 % for the ANN and the MaxLike, respectively. When the random sampling method was applied, the ANN had a global accuracy of 69.6 %, and the MaxLike had an accuracy of 62.1 %, considering the total study area in relation to the reference map.

Geospatial variability of soil CO2–C exchange in the main terrestrial ecosystems of Keller Peninsula, Maritime Antarctica

Soils and vegetation play an important role in the carbon exchange in Maritime Antarctica but little is known on the spatial variability of carbon processes in Antarctic terrestrial environments. The objective of the current study was to investigate (i) the soil development and (ii) spatial variability of ecosystem respiration (ER), net ecosystem CO2 exchange (NEE), gross primary production (GPP), soil temperature (ST) and soil moisture (SM) under four distinct vegetation types and a bare soil in Keller Peninsula, King George Island, Maritime Antarctica, as follows: site 1: moss-turf community; site 2: moss-carpet community; site 3: phanerogamic antarctic community; site 4: moss-carpet community (predominantly colonized by Sanionia uncinata); site 5: bare soil. Soils were sampled at different layers. A regular 40-point (5×8 m) grid, with a minimum separation distance of 1m, was installed at each site to quantify the spatial variability of carbon exchange, soil moisture and temperature. Vegetation characteristics showed closer relation with soil development across the studied sites. ER reached 2.26μmolCO2m(-2)s(-1) in site 3, where ST was higher (7.53°C). A greater sink effect was revealed in site 4 (net uptake of 1.54μmolCO2m(-2)s(-1)) associated with higher SM (0.32m(3)m(-3)). Spherical models were fitted to describe all experimental semivariograms. Results indicate that ST and SM are directly related to the spatial variability of CO2 exchange. Heterogeneous vegetation patches showed smaller range values. Overall, poorly drained terrestrial ecosystems act as CO2 sink. Conversely, where ER is more pronounced, they are associated with intense soil carbon mineralization. The formations of new ice-free areas, depending on the local soil drainage condition, have an important effect on CO2 exchange. With increasing ice/snow melting, and resulting widespread waterlogging, increasing CO2 sink in terrestrial ecosystems is expected for Maritime Antarctica.

Soils of the South Orkney and South Shetland Islands, Antarctica

The present Chapter presents an overview on soils from Maritime Antarctica, comprising ice-free areas distributed along the South Orkney (SOI) and South Shetland Islands (SSI). Published and novel data were compiled, with focus on pedogenesis and soils geography, in a total of 365 pedons, of which 71 % are from King George Island. Seven soil-forming processes occur, including cryoturbation, gleization, melanization, podzolization, paludization, and phosphatization. Six soil orders have been reported in the SOI and SSI, including Gelisols, Entisols, Inceptisols, Histosols, Mollisols, and Spodosols, which represent half of the orders in ST. Gelisols are predominant at altitudes above 30 m.a.s.l. to 100 m.a.s.l., where discontinuous permafrost exists. The most abundant great group is the Haploturbels, illustrating the importance of cryoturbation. We conclude with a summary of the current knowledge on soil formation and distribution in the SOI and SSI, and a prospect of future research needs and questions.

Estratificação e caracterização ambiental da área de preservação permanente do Rio Guandu/RJ

RESUMO – O Rio Guandu e a principal fonte de abastecimento de agua da regiao metropolitana do Rio de Janeiro, atendendo a, aproximadamente, nove milhoes de pessoas. Este trabalho estratificou e caracterizou ambientalmente a Area de Preservacao Permanente (APP) do Rio Guandu (faixa marginal de 100m), atraves da analise de aerofotos digitais nao convencionais, obtidas a partir de uma câmera digital de pequeno formato, adaptada a um helicoptero (as aerofotos foram agrupadas em mosaicos para facilitar as etapas do geoprocessamento). A regiao correspondente a APP foi estratificada em quatro ambientes com caracteristicas ecologicas distintas: Ambiente 1 (leito encaixado), Ambiente 2 (varzea fluvial), Ambiente 3 (planicie aluvionar) e Ambiente 4 (fluviomarinho). A partir da sobreposicao dos mapas de uso da terra, da proximidade da area urbano-industrial e da vegetacao nativa, foi gerado um mapa do grau de degradacao dos ambientes. Os usos predominantes foram pastagem (38%) e agricultura (18%). Os fragmentos florestais totalizaram apenas 11,6% da APP. Segundo a metodologia utilizada, o Ambiente 4 apresentou 51% de sua area, com um grau alto a muito alto de degradacao, e o Ambiente 3 apresentou melhor estado de conservacao em comparacao aos demais. Os resultados sugeriram que a predominância das atividades agropecuarias, a proximidade de grandes centros urbanos e a area muito reduzida dos fragmentos florestais na APP do Rio Guandu podem comprometer a qualidade desse manancial.

Environmental Assessment of Admiralty Bay, King George Island, Antarctica

Monitoring has been developed by Antarctic Programmes such as Antarctic New Zealand (www.antarcticanz.govt.nz) and the US Antarctic Programme (USAP) (http://www.usap.gov) considering expansion of human activities and inevitable environmental.

Estimativa da área ocupada por reflorestamentos no estado do Rio de Janeiro

Este estudo fundamentou-se em levantamento e cadastro preliminar dos reflorestamentos existentes no Estado do Rio de Janeiro, por meio de tecnicas de geoprocessamento e coleta de informacoes no campo. A area reflorestada encontrada foi de 18.426,96 ha, que corresponde a 0,42% do territorio do Estado. Grande parte dos reflorestamentos consiste em plantios de eucalipto (98%), seguido de pinus (0,8%), e o restante encontra-se distribuido em outras 10 especies. A Regiao do Medio Paraiba foi a que mais contribuiu para area reflorestada no Estado (46,6%). O volume de madeira estimado para o eucalipto foi de quase dois milhoes de metros cubicos. Este estudo serviu para cristalizar a percepcao corrente entre todos aqueles que militam no setor florestal fluminense, de que e incipiente a area plantada e o estoque de madeira oriunda de reflorestamentos existentes no Estado do Rio de Janeiro.

SOLOS DA ÁREA INDÍGENA YANOMAMI NO MÉDIO RIO CATRIMANI, RORAIMA

Em Roraima, a distribuicao espacial das populacoes indigenas identifica um cenario de busca constante de solos capazes de sustentar uma agricultura itinerante. Este trabalho teve como objetivo estabelecer relacao entre a compreensao dos solos por parte dos Yanomami da regiao do medio Catrimani e o Sistema Brasileiro de Classificacao de Solos, bem como avaliar o seu tipo de uso em funcao de analises quimicas para diagnostico da fertilidade do solo. O trabalho foi executado em duas etapas. A primeira consistiu em visitas a oito malocas para estudar os solos. Foram coletadas amostras em trincheiras ate 1,50 m de profundidade para analise e classificacao dos solos e (em prospeccoes com o trado) nas profundidades de 0-10 a 10-30 cm, em 21 tipos de uso agricola, e da area de floresta para analises quimicas de fertilidade. A segunda fase foi uma oficina, abordando os sistemas de exploracao agricola, com duracao de 20 h. Focalizou-se a discussao sobre a compreensao do meio ambiente (Urihi)(1) e sistemas de producao agricolas e sobre a importância do uso correto do conhecimento dos solos. Os solos sao denominados pelos Yanomami em funcao das caracteristicas morfologicas, pelos teores de materia orgânica e pela presenca de minhocas, e da posicao na paisagem - a escolha para agricultura e fundamentada nessas caracteristicas. As praticas agricolas consistem da derrubada da mata nativa, queima e plantio das culturas em separado. Os solos descritos na area foram: Argissolo Vermelho-Amarelo (Maxita a uuxi wake axi), Argissolo Amarelo (Maxita a axi), Latossolo Amarelo (Maxita a axi) e Plintossolo (Maxita a axi a maamaxipe). O processo de derruba e queima promove um incremento inicial do teor de Ca e K trocaveis e P assimilavel devido a contribuicao das cinzas, o que permite a exploracao das areas por um periodo maximo de tres anos.In Roraima, the spatial distribution of indigenous peoples indicates a background of constant search for soils capable of sustaining shift cultivation. This study aimed to establish a relationship between the understanding of soil by the Yanomami tribe from the mid-Catrimani river region and the Brazilian System of Soil Classification and evaluate the type of agricultural land use according to soil fertility tests, in two steps. The first consisted of visiting eight Indian communities to collect soil samples at 21 sites with different types of agriculture and forests, both from profile soil (depth 0-1.50 m) and pits (depth 0-0.1 m and 0.1-0.3 m) for laboratory analysis. The second step was a workshop addressing the shift cultivation systems (duration 20 h). The discussion focused on the understanding of the environment (Urihi) and agricultural production systems, and on the importance of the correct use of knowledge of the soil and its fertility. Soils are named according to their morphology and position in the landscape by the Yanomami. The choice of agricultural areas is based on these features, aside from the organic matter content and the presence of earthworms. Agricultural practices comprise clearing and burning of the native forest immediately before planting a set of separate crops. The soils described in the area were classified according to the Brazilian taxonomic system as follows: Red Yellow Argisol (Maxita a uuxi wake axi), Yellow Argisol (Maxita a axi) Yellow Latosol (Maxita a axi) and Plintosol (Maxita a axi a maaxipe). Slashing and burning initially increases exchangeable Ca, K and available P due to the contribution of the ashes, which allows an agricultural exploitation of these areas for a maximum period of three years.

Proposta de metodologia para zoneamento ambiental de plantio de eucalipto

The objective of this work was to develop a method for environmental zoning of eucalyptus plantations, to identify areas where eucalyptus planting could be developed, and to determine suitability of such areas. The study area was the County of Vassouras, in the State of Rio de Janeiro, considering physical data, environmental legislation, urban areas, and the municipal land use plan. The areas for permanent preservation, as well as the conservation units and areas for industrial expansion, as defined in the county land use plan, plus areas nearby the city were considered restricted for the planting of eucalyptus trees. Vassouras is 552 km² large. Approximately 144 km² are suitable eucalyptus planting, of which 97% are now used for pastures. Approximately 50% of the area suitable for eucalyptus is of average suitability, whereas the class of highest suitability occupies about 30%. The less suitable areas correspond to 20% of the remaining 144 km 2 .

Elaboração de um sistema de classificação da capacidade de suporte em ambiente semi-árido

This work aimed as general objective, to identify the farmers of the Settlement Projects of Agricultural Reform in the State of Rio Grande do Norte, with the natural resources of their respective areas and later to elaborate a system of classification of support capacity of the ambient. For the purpose, ten Settlement Projects were selected in the western part of the state, characterized by semi-arid regime in an area of 30.000 ha where qualitative and quantitative parameters of the soil where edalfo, forest and water resources were identified. It was verified that all Settlement Projects presented number of settlers more than the ambient could support, demonstrating the need to reevaluate the size of the agricultural module adopted in these areas, as well as the satisfactory offer of water which allows better exploration of the agricultural potential of the soils of the area, thereby decreasing the pressure on the forest resources.

COMPOSIÇÃO FLORÍSTICA E ESTRUTURA DE UM CERRADO SENSU STRICTO NO OESTE DA BAHIA

In this study it was characterized the structure and floristic of the cerradosensu stricto located in Jaborandi, a city of western Bahia State. All individuals were sampled based on diameter height (D30cm ≥ 5cm) present in a sample area of two hectares comprising 20 plots of 1000 m2 (20m x 50m). Individuals were found in total of 2054 (1027 ind.ha-1), on a basal area of 8.24 m2.ha-1and 58 species belonging to 42 genera and 24 families. Fabaceae had the largest number of species (12), followed by Myrtaceae (8) and Vochysiaceae (5). The phytosociological descriptors evaluated, have shown a community characterized by the presence of a few dominant species, where most can be regarded as unusual and rare. The diametrical structure and height presented a balanced vegetation, predominantly composed by small individuals. Here, richness is relevant, as well as local diversity, which was estimated at 2.95 nats.ind-1 by the Shannon-Wiener index.