Clenio Nailto Pillon

Conteúdo de carbono orgânico em planossolo háplico sob sistemas de manejo do arroz irrigado

Nos solos de varzea da regiao Sul do Rio Grande do Sul, onde um milhao de hectares sao cultivados com arroz irrigado por alagamento em diferentes sistemas de manejo, a influencia da condicao de ma drenagem e alternância entre ciclos de oxidacao e reducao sobre o conteudo de C orgânico do solo (COS) e pouco conhecida. Este estudo foi realizado em um experimento de longa duracao (21 anos), localizado no municipio do Capao do Leao, RS, com o objetivo de avaliar o efeito de sistemas de manejo do arroz irrigado sobre os estoques de COS e das fracoes fisicas da materia orgânica em um Planossolo Haplico. O fracionamento fisico da materia orgânica do solo foi realizado pelo metodo densimetrico, em amostras de solo coletadas das camadas de 0-0,025; 0,025-0,05; 0,05-0,10; e 0,10-0,20 m, nos tratamentos: ST- Sistema tradicional de cultivo um ano com arroz (preparo convencional) e dois anos com pousio; APC- Sistema de cultivo continuo de arroz (preparo convencional) e controle de invasoras com herbicida; APD- Sucessao azevem/arroz (plantio direto); e SN- Solo mantido com vegetacao natural (campo nativo). O sistema com arroz/azevem em plantio direto APD foi mais eficiente em manter os estoques de COS e da fracao leve livre ate 0,05 m de profundidade, em comparacao com o ST e APC. A fracao leve oclusa nao se mostrou sensivel aos efeitos dos diferentes sistemas de manejo, sugerindo para o solo de varzea baixa eficiencia da protecao fisica da MOS por oclusao em agregados, o que pode estar relacionado aos efeitos da condicao de ma drenagem no processo de agregacao. A umidade excessiva no inverno e o alagamento durante os cultivos de arroz estariam proporcionando agregacao transitoria entre cultivos. A quantidade de CO nesse Planossolo, tanto entre os sistemas de cultivo quanto em profundidade, deve-se principalmente a fracao pesada, que e a fracao mais estavel e mais dificil de ser degradada.

Medicinal plants: knowledge transmission in families of ecological farmers in souther Rio Grande do Sul

O objetivo deste estudo foi investigar o processo de transmissao do conhecimento relacionado as plantas medicinais entre as geracoes familiares, no contexto de agricultores de base ecologica da regiao sul do Rio Grande do Sul. Trata-se de um estudo qualitativo realizado com oito familias de agricultores, totalizando 19 entrevistados, residentes nos municipios de Pelotas, Morro Redondo, Cangucu e Arroio do Padre, entre janeiro e maio de 2009. A analise dos dados foi realizada atraves do metodo hermeneutico-dialetico. A familia foi referida como a principal fonte na transmissao do conhecimento em relacao as plantas medicinais. A maioria dos sujeitos informou primeiro realizar o tratamento com as plantas medicinais para em seguida buscar o servico formal de saude. A construcao do conhecimento relacionado as plantas medicinais pelas familias e predominantemente oral, realizada atraves do convivio diario entre seus membros e compartilhada com os demais membros da comunidade na qual estao inseridos.The aim of this study was to investigate the process of knowledge transmission related to medicinal plants among family generations in the context of ecological farmers in Southern Rio Grande do Sul. This qualitative study was conducted with eight farming families, comprising 19 respondents living in the municipalities of Pelotas, Morro Redondo, Canguçu and Arroio do Padre. The interviews took place from January to May 2009. Data analysis was performed using the hermeneutic-dialectic method. The family was referred to as the main source in the transmission of knowledge about medicinal plants. Most subjects reported first completing treatment with medicinal plants, to then seek formal health service. The construction of knowledge related to medicinal plants by the families is predominantly oral, and takes place by the daily contact between its members and is shared with other members of the community to which they belong.

Fracionamento químico e físico da matéria orgânica de um argissolo vermelho sob diferentes sistemas de uso

The objective of this study was to evaluate the total organic carbon and the physical and chemical fractions of organic matter in an Alfisol under different use systems. The land use systems evaluated was homogeneous forestry of Eucalyptus grandis, agrosilvopastoral system and native grassland, in layers from 0.000-0.025 and 0.025-0.075m depth. The coarse fraction (CFG) and the carbon associated minerals (CAM) were obtained by physical fractionation. The free light fraction (FLL), light occluded (FLO) and heavy (FP) were obtained by densimetric physical fractionation. The non-humicfractions (NH), fulvic acid (AF), humic acid (HA) and humin (HU) were obtained by chemical fractionation. The Eucalyptus grandis system promoted higher total organic carbon, CFG, FLL and FLO and AF. In the surface layer, the protective recalcitrance mechanisms by organic matter molecular and chemical stabilization are overlapping stability which result from aggregates occlusion. As is difficult to form aggregates due to sandy soil matrix, carbon youth which enter the system is decomposed by microorganisms going to a more advanced stage of decomposition, forming in this case associations with silt and clay particles. This occurs in soils where the clay percentage is low. Through the fractionation it was observed that most of the soil organic matter is stored in the form of HU.

AGREGAÇÃO E FRAÇÕES FÍSICAS DA MATÉRIA ORGÂNICA DE UM ARGISSOLO VERMELHO SOB SISTEMAS DE USO NO BIOMA PAMPA

Pasture-agroforestry systems have become an important strategy for the use of sandy soils in the Pampa Biome. The purpose of this study was to evaluate the aggregation, total organic C (TOC) and total nitrogen (TN), carbon of the physical fractions and humification degree of organic matter (OM). Evaluations were conducted in an Alfisol under homogenous eucalyptus forest (HF), between the rows of a pasture-agroforestry system (PA) and in native pasture (NP) in the layers 0.000-0.025, 0.025-0.075, 0.075-0.125, and 0.125-0.225 m. Disturbed samples were collected to evaluate water-stable aggregates (WSA %), TOC and TN. The physical (granulometrical and densimetrical) fractionation of OM was carried out, and the free light fraction (FLF) and occluded light fraction (OLF) of OM in the surface layer subjected to Fourier Transform Infrared (FTIR) and Electron Paramagnetic Resonance (EPR) analyses. The WSA and mean weight diameter in the layer 0.025-0.075 m indicated a greater degradation of the PA soil. Higher levels of TOC, TN, coarse fraction carbon (CFC), carbon associated with minerals (CAM), FLF and OLF in the surface layer were observed in HF. Between land uses, the FTIR spectra were similar. However, the FLF had more intense bands in the region of 1072 cm-1, suggesting higher amounts of polysaccharides than in the OLF. The spin densities obtained by EPR at OLF were higher than of FLF, indicating a higher humus fraction.

Carbono e nitrogênio de um Argissolo Vermelho sob floresta, pastagem e mata nativa

The monitoring of soil organic matter content (MOS) has been considered soil quality indicator. Few studies, in Southern Brazil, have evaluated changes in the total organic carbon (COT), total nitrogen (NT) and in the lability of MOS in forestry systems. This study aimed to evaluate the COT, NT and free light fraction of MOS from 0.00 to 0.05, 0.05 to 0.10, 0.10 to 0.20 and 0.20 to 0.40m depths of the Alfisol under eucalyptus, native forest and pasture. In addition, it was quantified the stock of COT and NT in plant residues in forestry areas. The concentration of COT and NT and labile fractions of MOS increased favored by the addition of vegetables residues and by minimizing soil disturbance.

Tensile strength and friability of an Alfisol under agricultural management systems

Management systems may influence the structural quality of soils. Tensile strength (TS) and friability (F) are indicators of soil structural quality. The aim of this study was to evaluate the TS and F of an Alfisol under different management systems. The treatments were as follows: (i) soil under conventional system with growing maize after tobacco cultivation, (ii) soil under conventional system with growing maize after use as pasture, (iii) soil under natural pasture, and (iv) a natural area with predominance of spontaneous vegetation. TS and F were evaluated at depths of 0.00-0.05 and 0.05-0.10 m. The water content of soil aggregates, soil particle-size distribution, total organic carbon, carbon in the coarse fraction and carbon associated with minerals were also determined. The increase in clay content and soil organic carbon influences the values of TS. The lowest TS was for the soil under maize cultivation after tobacco in the conventional system. Soil under natural area in the 0.05-0.10 m layer was classified as slightly friable, while other systems were classified as friable. Evaluations of the structural quality of soils under management systems can be performed using TS. However, F was not efficient in detecting changes between the different management systems.

Condição estrutural de um argissolo no Rio Grande do Sul, em floresta nativa, em pastagem cultivada e em povoamento com eucalipto

This study aimed to define the critical limits of physico-hidric attributes to areas under forest and pasture and to evaluate the intensity of compression of these uses in a Hapludalf in South Brazil. The use of soils were: Native Forest – formed for arboreal species; Pasture – five years old, constituted of Brachiaria brizantha associated with Paspalum lourai and Trifolium sp.; Eucalipto 20 - Eucalyptus saligna with 20 years old, installed under conventional tillage; Eucalipto 4,5 - Eucalyptus saligna under 2nd rotation, 4.5 years old. It was evaluated the hydraulic conductivity, macro, micro and total porosity and bulk density. The eucalypt is a potential crop to be used in recovering degraded areas with no commercial objective. Soil compression increase bulk density and decrease macroporosity and total porosity until the layer of 0.40 m in eucalypt for commercial use and until 0.10 m in pasture. Values based on restriction and yield of annual crops or in the least limiting water range have potential to be used as restrictive values for perennial and pasture crops

Multimineral and Organic Composition of a Liquid By-Product from the Pyrobituminous Shale Pyrolysis Process and its Potential Use in Agriculture

Pyrolysis of pyrobituminous shale rock to extract products such as fuel oil and gas generate a liquid by-product called shale water (SW). In this study, the physical-chemical characterization of SW was performed and the effects on plant growth, mineral nutrition, and food safety were evaluated when applied via foliar in lettuce crop. Shale water showed a great diversity of organic compounds, minerals, and trace elements. The application of SW in lettuce resulted in no phytotoxic effect or accumulation of toxic elements to human health within the doses tested, and increased yield and the accumulation of several mineral nutrients in the leaves. The absorption and accumulation of zinc, copper, cobalt, molybdenum, and manganese was also improved when these minerals were applied together with SW. These results suggest that SW plays a role as a biostimulant and could be used in agriculture as a safety alternative to increase yield and biofortify crops.

Plantas medicinales: transmisión de conocimientos en las familias de agricultores de base ecológica en el Sur de RS

O objetivo deste estudo foi investigar o processo de transmissao do conhecimento relacionado as plantas medicinais entre as geracoes familiares, no contexto de agricultores de base ecologica da regiao sul do Rio Grande do Sul. Trata-se de um estudo qualitativo realizado com oito familias de agricultores, totalizando 19 entrevistados, residentes nos municipios de Pelotas, Morro Redondo, Cangucu e Arroio do Padre, entre janeiro e maio de 2009. A analise dos dados foi realizada atraves do metodo hermeneutico-dialetico. A familia foi referida como a principal fonte na transmissao do conhecimento em relacao as plantas medicinais. A maioria dos sujeitos informou primeiro realizar o tratamento com as plantas medicinais para em seguida buscar o servico formal de saude. A construcao do conhecimento relacionado as plantas medicinais pelas familias e predominantemente oral, realizada atraves do convivio diario entre seus membros e compartilhada com os demais membros da comunidade na qual estao inseridos.The aim of this study was to investigate the process of knowledge transmission related to medicinal plants among family generations in the context of ecological farmers in Southern Rio Grande do Sul. This qualitative study was conducted with eight farming families, comprising 19 respondents living in the municipalities of Pelotas, Morro Redondo, Canguçu and Arroio do Padre. The interviews took place from January to May 2009. Data analysis was performed using the hermeneutic-dialectic method. The family was referred to as the main source in the transmission of knowledge about medicinal plants. Most subjects reported first completing treatment with medicinal plants, to then seek formal health service. The construction of knowledge related to medicinal plants by the families is predominantly oral, and takes place by the daily contact between its members and is shared with other members of the community to which they belong.