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Recovery of degraded pasture in Rondônia: macronutrients and productivity of brachiaria brizantha; Recuperação de pastagem degradada em Rondônia: macronutrientes e produtividade da brachiaria brizantha

NORONHA, Norberto Cornejo; ANDRADE, Cristiano Alberto de; LIMONGE, Fernando Célio; CERRI, Carlos Clemente; CERRI, Carlos Eduardo Pellegrino; PICCOLO, Marisa de Cássia; FEIGL, Brigitte Josefine
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.39%
Pasture is the main form of land use in Amazonia. Over time the pasture grass loses vigor and yields decrease, indicating a certain degree of degeneration. The main causes of degradation are lack of pasture maintenance and subsequent weed infestation, the choice of regionally unsuitable forage species and excessive grazing. The main purpose of this study was to evaluate the impact of different recovery managements on soil chemical properties and grass yield of a degraded pasture in Rondônia. For this purpose, an experiment was installed in October 2001, consisting of five treatments: C = control; HA = harrowing + NPK + micronutrients; HE = Herbicide + NK + micronutrients; R = No-tillage rice + NPK + micronutrients; and S = No-tillage soybean + PK + micronutrients. The following N, P and K sources were used: ammonium sulfate for N, calcined phosphate for P and potassium chloride for K. The experiment was arranged in a randomized block design with four replications. The shoot dry matter yield of the grass was analyzed as of the 35th month of experimentation, in a dry and a rainy period. Phosphorus fertilization resulted in significant increases in Ca2+ and Mg2+ and increasing trend of P in the topsoil in the initial months of the experiment in treatments HA and S and increases in Ca2+ and P (trend) in the treatment R. The cumulative production of Brachiaria brizantha...

Yield and botanical composition of a mixed grass-legume pasture in response to maintenance fertilization; Produção e composição botânica de uma pastagem consorciada de gramínea e leguminosa em resposta à adubação de manutenção

ANDRADE, Carlos Mauricio Soares de; VALENTIM, Judson Ferreira; PEREIRA, João Batista Martiniano; FERREIRA, Aliedson Sampaio
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.35%
This study was carried out on a low-productive Brachiaria brizantha cv. Marandu pasture, mixed with Arachis pintoi cv. Belmonte (forage peanut), established 13 years ago in a Red-Yellow Latosol in Acre State, western Brazilian Amazon. The purpose was to evaluate the response of this pasture to different fertilizer combinations, aiming at identifying the nutritional factors responsible for the fall of pasture carrying capacity and for the reduced vigor of forage peanut. It was used a randomized complete block design, with three replications and 12 combinations of nitrogen, phosphorus, potassium, lime, sulfur, and micronutrients (100 kg/ha of N, P2O5 and K2O; 300 kg/ha of dolomitic lime; 30 kg/ha of sulfur and FTE BR-10). Fertilizers were broadcast in 5 × 5-m plots, and the experimental area was isolated from grazing for 35 days. Pasture response to fertilizations showed that nitrogen was the main limiting nutrient to forage production. The other nutrients, applied singly or in a combined way, without nitrogen source, did not change dry matter accumulation rate. Overall, fertilizations with nitrogen provided dry matter accumulation rate of 115 kg/ha/day in comparison to only 32 kg/ha/day when nitrogen was not applied. There was no response from forage peanut to fertilization...

Avaliação da qualidade física de solos em pastagens degradadas da Amazônia; Evaluation of the soil physical quality in degraded pastures of the Amazonian

Neves Junior, Afrânio Ferreira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/01/2006 PT
Relevância na Pesquisa
36.4%
A região amazônica possui extensas áreas que foram desmatadas e convertidas em sistemas de pastagens. A falta de técnicas na implantação e no manejo destes sistemas resultou em inúmeras áreas de pastagens degradadas. A condução de experimentos de campo visando a reversão deste quadro está sendo avaliada no presente estudo. A área em estudo está localizada na Fazenda Nova Vida, município de Ariquemes, Estado de Rondônia/RO. O solo da fazenda foi classificado como Latossolo Vermelho Amarelo. Os tratamentos utilizados consistiram em dois sistemas de plantio direto (arroz e soja), aplicação de herbicida no controle de invasoras, operação de gradagem e a pastagem controle. O Intervalo Hídrico Ótimo (IHO), a densidade do solo, resistência à penetração, macroporosidade, microporosidade, porosidade total e permeabilidade do solo ao ar foram determinadas. Não foi verificada diferença significativa entre os tratamentos utilizados. O solo estudado não apresentou restrições físicas ao crescimento de plantas. As variações na estrutura do solo são melhor avaliadas quando os fatores que afetam diretamente o crescimento de plantas são integrados em um único parâmetro. As propriedades físicas determinadas foram menos sensíveis que o IHO às alterações provocadas pelos sistemas de manejo. O IHO possui um grande potencial como índice de qualidade física do solo na avaliação de experimentos que visam a recuperação de pastagens degradadas...

Nitrogênio e enxofre na implantação do capim-Marandu em substituição ao capim-Braquiária em degradação num solo com baixa matéria orgânica; Nitrogen and sulfur for Marandu grass establishment in replacing signal grass under degradation in a low organic matter soil

Batista, Karina
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 29/09/2006 PT
Relevância na Pesquisa
46.3%
A deficiência de nitrogênio tem sido apontada como uma das principais causas da degradação de pastagens, mas o suprimento de enxofre também é relevante nessa situação. Objetivou-se avaliar os efeitos das combinações entre doses de nitrogênio e de enxofre em características produtivas, fisiológicas e nutricionais da planta e nos atributos químicos do solo, na implantação do capim-Marandu (Brachiaria brizantha cv. Marandu) em Neossolo Quartzarenico proveniente de área de capim-Braquiária (Brachiaria decumbens) em degradação, com baixo teor de matéria orgânica. O experimento foi conduzido em casa-de-vegetação, em Piracicaba, Estado de São Paulo, no período de dezembro de 2004 a abril de 2005. Utilizou-se esquema fatorial 52 fracionado, com 13 combinações para as doses de nitrogênio e enxofre, em mg dm-3: 0-0; 0-20; 0-40; 100-10; 100-30; 200-0; 200-20; 200-40; 300-10; 300-30; 400-0; 400- 20 e 400-40, as quais foram distribuídas em delineamento estatístico de blocos ao acaso, com quatro repetições. Foram realizados três cortes nas plantas e a cada corte era coletada uma amostra de solo de cada unidade experimental. Após o terceiro corte as raízes foram separadas do solo e tiveram o comprimento e a superfície avaliados. Os resultados demonstraram que o fornecimento de nitrogênio foi fundamental para o crescimento inicial e adequado estabelecimento do capim-Marandu. Quando o nitrogênio foi fornecido em altas doses foi necessário cuidar do fornecimento de enxofre para a maximização da produção do capim- Marandu...

Balanço de água e de nitrogênio em uma microbacia coberta por pastagem no litoral norte do Estado de São Paulo; Nitrogen and water budget of a small catchment covered by pasture in the north coast of Sao Paulo State, Brazil

Salemi, Luiz Felippe
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 16/06/2009 PT
Relevância na Pesquisa
36.35%
A Mata Atlântica é o bioma mais ameaçado do Brasil. Sua degradação substancial ocorreu desde a chegada dos europeus ao país por meio da mudança de uso solo e pela exploração da floresta. No entanto, pouco se sabe a respeito das conseqüências hidrológicas e biogeoquímicas da mudança de uso do solo nos domínios do referido ecossistema. Neste contexto, as microbacias hidrográficas têm sido objeto de muitos estudos devido sua alta sensibilidade aos processos hidrológicos e biogeoquímicos ocorrentes dentro delas. No presente estudo, calculou-se o balanço hídrico anual de uma microbacia coberta por pastagem na região do litoral norte do Estado de São Paulo. Essa bacia originalmente era coberta por floresta ombrófila densa. Em adição, amostrou-se água do escoamento do riacho, escoamento superficial, solução do solo (30, 50 e 90 cm de profundidade), água subterrânea, e precipitação de 05/12/2007 à 04/12/2008 para a análise de nitrogênio inorgânico. O conteúdo de nitrogênio (N-NH4 + e N-NO3 -) foi determinado por análise por injeção em fluxo (FIA). Com o intuito de elucidar os processos hidrológicos que geram escoamento direto, mediu-se a condutividade hidráulica do solo em condição de saturação a 15...

The relationship between pasture degradation and soil properties in the Brazilian amazon: a case study

Muller, MML; Guimaraes, M. F.; Desjardins, T.; Mitja, D.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 279-288
ENG
Relevância na Pesquisa
46.76%
Pasture degradation is one of the greatest problems related to land use in the Amazon region, forcing farmers to open new forest areas. Many studies have identified the causes and the factors involved in this degradation process, in an attempt to reverse the situation. The purpose of this study was to examine the relationship between pasture degradation and some soil properties, to try to identify the most significant soil features in the degradation process. A cattle raising farm in the eastern Amazon region, with pastures of different ages and degrees of degradation, was used as the site for this study: a primary forest area, PN; three Guinea grass (Panicum maximum Jacq.) pastures in an increasingly degraded sequence-P1, P2 and P3; one Gamba grass (Andropogon gayanus Kunth) pasture following an extremely degraded Guinea grass pasture, P4. Aboveground phytomass data showed differences between the pastures, reflecting initially observed degradation levels. Grass biomass decreased sharply from P1 to P2 and disappeared at P3. Pasture recovery with Gamba grass at P4 was very successful, with grass biomass higher than P1 and weed biomass smaller than P2 and P3. Root biomass also decreased with pasture degradation. Soil bulk density increased with pasture decrease at the topsoil layer. Results from the soil chemical analysis showed that there were no signs of decrease in organic carbon and total nitrogen after the forest was transformed into pasture. In all pastures...

Spatial variability of forage yield and soil physical attributes of a Brachiaria decumbens pasture in the Brazilian Cerrado

Pariz, Cristiano Magalhães; Carvalho, Morel de Passos e; Chioderoli, Carlos Alessandro; Nakayama, Fernando Takayuki; Andreotti, Marcelo; Montanari, Rafael
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: 2111-2120
ENG
Relevância na Pesquisa
36.4%
The objective of this study was to analyze variability, linear and spatial correlations of forage dry mass yield (FDM) and dry matter percentage (DM%) of Brachiaria decumbens with the bulk density (BD), gravimetric (GM) and volumetric (VM) moisture, mechanical resistance to penetration (RP) and organic matter content (OM), at depths 1 (0-0.10 m) and 2 (0.10-0.20 m), in a Red Latosol (Oxisol), in order to select an indicator of soil physical quality and identify possible causes of pasture degradation. The geostatistical grid was installed to collect soil and plant data, with 121 sampling points, over an area of 2.56 ha. The linear correlation between FDM × DM% and FDM × BD2 was low, but highly significant. Spatial correlations varied inversely and positively, respectively. Except for DM% and BD, at both depths, the other attributes showed average to high variability, indicating a heterogeneous environment. Thus, geostatistics emerges as an important tool in understanding the interactions in pasture ecosystems, in order to minimize possible causes of degradation and indicate better alternatives for soil-plant-animal management. The decrease in FDM and increased BD1 are indicators of physical degradation (compaction) of Red Latosol (Oxisol)...

Soil erodibility assessment in a pasture and forest remnant using the inderbitzen device

Ribeiro, A. I.; Gonzalez, L. F.; Longo, R. M.; de Medeiros, G. A.; Rosa, André Henrique; Lourenço, Roberto Wagner; Fengler, F. H.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 49-55
ENG
Relevância na Pesquisa
36.48%
Brazil has the largest cattle herd in the world with approximately 200 million head. An important feature of the Brazilian cattle industry is that most of its herd is raised on pasture, which constitutes one of the most economical and practical ways to produce and provide food for cattle. However, this production model is mishandled and can lead to soil degradation. Maintaining soil quality is essential for the conservation of natural ecosystems and the areas of production, thus soil quality improves the conditions for biogeochemical cycles. In this context, the objective of this study was to develop a device for testing the Inderbitzen way of assessing soil erodibility in two situations of usage and occupation. Therefore, one area was used as a sample collection occupied by grazing and the other as a forest fragment; both located in the city of Sorocaba in Sao Paulo State, Brazil. Thus, we concluded that the proposed device - the Inderbitzen - proved capable of assessing soil erodibility of the pasture and remnant forest. Accordingly, there was a tendency for a smaller loss of forest soils in the remnant when compared to the degraded pasture. The greatest resistance of the soil erosion in the forest remnant may be associated with the amount of organic matter released by the forest litter in all its diversity...

Soil erodibility assessment in a pasture and forest remnant using the Indrbitzen device

Ribeiro, Admilson Irio; Gonzáles, Luis Fernando; Longo, Regina Márcia; Medeiros, Gerson Araújo de; Rosa, André Henrique; Lourenço, Roberto Wagner; Fengler, Felipe Hashimoto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 49-56
ENG
Relevância na Pesquisa
36.35%
Brazil has the largest cattle herd in the world with approximately 200 million head. An important feature of the Brazilian cattle industry is that most of its herd is raised on pasture, which constitutes one of the most economical and practical ways to produce and provide food for cattle. However, this production model is mishandled and can lead to soil degradation. Maintaining soil quality is essential for the conservation of natural ecosystems and the areas of production, thus soil quality improves the conditions for biogeochemical cycles. In this context, the objective of this study was to develop a device for testing the Inderbitzen way of assessing soil erodibility in two situations of usage and occupation. Therefore, one area was used as a sample collection occupied by grazing and the other as a forest fragment; both located in the city of Sorocaba in Sao Paulo State, Brazil. Thus, we concluded that the proposed device – the Inderbitzen – proved capable of assessing soil erodibility of the pasture and remnant forest. Accordingly, there was a tendency for a smaller loss of forest soils in the remnant when compared to the degraded pasture. The greatest resistance of the soil erosion in the forest remnant may be associated with the amount of organic matter released by the forest litter in all its diversity...

Fertility and acidity status of latossolos (oxisols) under pasture in the Brazilian Cerrado

Vendrame,Pedro R.S.; Brito,Osmar R.; Guimarães,Maria F.; Martins,Éder S.; Becquer,Thierry
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
36.48%
The Cerrado region, with over 50 million hectares of cultivated pasture, provides 55% of Brazilian beef production. Previous investigations have shown that about 70-80% of this pasture is affected by some kind of degradation, leading to low productivity. However, until now, few surveys have been carried out on a regional scale. The aim of the present work is both to assess the fertility and acidity levels of Cerrado soils under pasture and compare the variability of the soils characteristics on a regional scale. Two soil depths were sampled in different places within the studied area: (1) a surface horizon (0.0-0.2 m) in order to evaluate its fertility and acidity status for pasture, and (2) a subsurface horizon (0.6-0.8 m), used for classification. Most of soils had levels of nutrients below the reference values for adequate pasture development. Whatever the texture, about 90% of soils had low or very low availability of phosphorus. Only 7 to 14% of soils had low pH, high exchangeable aluminum, and aluminum saturation above the critical acidity level. Except for nitrogen, no significant difference was found between Latossolos Vermelhos and Latossolos Vermelho-Amarelos.

Recovery of degraded pasture in Rondônia: macronutrients and productivity of brachiaria brizantha

Noronha,Norberto Cornejo; Andrade,Cristiano Alberto de; Limonge,Fernando Célio; Cerri,Carlos Clemente; Cerri,Carlos Eduardo Pellegrino; Piccolo,Marisa de Cássia; Feigl,Brigitte Josefine
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 EN
Relevância na Pesquisa
36.39%
Pasture is the main form of land use in Amazonia. Over time the pasture grass loses vigor and yields decrease, indicating a certain degree of degeneration. The main causes of degradation are lack of pasture maintenance and subsequent weed infestation, the choice of regionally unsuitable forage species and excessive grazing. The main purpose of this study was to evaluate the impact of different recovery managements on soil chemical properties and grass yield of a degraded pasture in Rondônia. For this purpose, an experiment was installed in October 2001, consisting of five treatments: C = control; HA = harrowing + NPK + micronutrients; HE = Herbicide + NK + micronutrients; R = No-tillage rice + NPK + micronutrients; and S = No-tillage soybean + PK + micronutrients. The following N, P and K sources were used: ammonium sulfate for N, calcined phosphate for P and potassium chloride for K. The experiment was arranged in a randomized block design with four replications. The shoot dry matter yield of the grass was analyzed as of the 35th month of experimentation, in a dry and a rainy period. Phosphorus fertilization resulted in significant increases in Ca2+ and Mg2+ and increasing trend of P in the topsoil in the initial months of the experiment in treatments HA and S and increases in Ca2+ and P (trend) in the treatment R. The cumulative production of Brachiaria brizantha...

Reclamation status of a degraded pasture based on soil health indicators

Santos,Cristiane Alcantara dos; Krawulski,Cristina Célia; Bini,Daniel; Goulart Filho,Tadeu; Knob,Adriana; Medina,Cristiane Conti; Andrade Filho,Galdino; Nogueira,Marco Antonio
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2015 EN
Relevância na Pesquisa
36.39%
Pasture degradation is a concern, especially in susceptible sandy soils for which strategies to recover them must be developed. Microbiological and biochemical soil health indicators are useful in the guindace of soil management practices and sustainable soil use. We assessed the success of threePanicum maximum Jacq. cultivars in the reclamation of a pasture in a sandy Typic Acrudox in the northwest of the state of Paraná, Brazil, based on soil health indicators. On a formerly degraded pasture withUrochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, a trial with threeP. maximum (cv. Massai, Tanzânia, or Mombaça) was conducted. Lime and phosphate were applied at set-up, and mineral N and K as topdressing. A remnant of degraded pasture adjacent to the trial was used as control. Twenty-three chemical, physical, microbiological and biochemical attributes were assessed for the 0-10 cm topsoil. The procedures for reclamation improved most of the indicators of soil health in relation to the degraded pasture, such as soil P, mineral N, microbial biomass C, ammonification rate, dehydrogenase activity and acid phosphatase. CO2 evolution decreased, whereas microbial biomass C increased in the pasture under reclamation, resulting in a lower metabolic quotient (qCO2) that points to a decrease in metabolic stress of the microbial community. The reclamation of the pasture withP. maximum...

Yield and botanical composition of a mixed grass-legume pasture in response to maintenance fertilization

Andrade,Carlos Mauricio Soares de; Valentim,Judson Ferreira; Pereira,João Batista Martiniano; Ferreira,Aliedson Sampaio
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 EN
Relevância na Pesquisa
46.35%
This study was carried out on a low-productive Brachiaria brizantha cv. Marandu pasture, mixed with Arachis pintoi cv. Belmonte (forage peanut), established 13 years ago in a Red-Yellow Latosol in Acre State, western Brazilian Amazon. The purpose was to evaluate the response of this pasture to different fertilizer combinations, aiming at identifying the nutritional factors responsible for the fall of pasture carrying capacity and for the reduced vigor of forage peanut. It was used a randomized complete block design, with three replications and 12 combinations of nitrogen, phosphorus, potassium, lime, sulfur, and micronutrients (100 kg/ha of N, P2O5 and K2O; 300 kg/ha of dolomitic lime; 30 kg/ha of sulfur and FTE BR-10). Fertilizers were broadcast in 5 × 5-m plots, and the experimental area was isolated from grazing for 35 days. Pasture response to fertilizations showed that nitrogen was the main limiting nutrient to forage production. The other nutrients, applied singly or in a combined way, without nitrogen source, did not change dry matter accumulation rate. Overall, fertilizations with nitrogen provided dry matter accumulation rate of 115 kg/ha/day in comparison to only 32 kg/ha/day when nitrogen was not applied. There was no response from forage peanut to fertilization...

Spatial variability of forage yield and soil physical attributes of a Brachiaria decumbens pasture in the Brazilian Cerrado

Pariz,Cristiano Magalhães; Carvalho,Morel de Passos e; Chioderoli,Carlos Alessandro; Nakayama,Fernando Takayuki; Andreotti,Marcelo; Montanari,Rafael
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2011 EN
Relevância na Pesquisa
36.4%
The objective of this study was to analyze variability, linear and spatial correlations of forage dry mass yield (FDM) and dry matter percentage (DM%) of Brachiaria decumbens with the bulk density (BD), gravimetric (GM) and volumetric (VM) moisture, mechanical resistance to penetration (RP) and organic matter content (OM), at depths 1 (0-0.10 m) and 2 (0.10-0.20 m), in a Red Latosol (Oxisol), in order to select an indicator of soil physical quality and identify possible causes of pasture degradation. The geostatistical grid was installed to collect soil and plant data, with 121 sampling points, over an area of 2.56 ha. The linear correlation between FDM × DM% and FDM × BD2 was low, but highly significant. Spatial correlations varied inversely and positively, respectively. Except for DM% and BD, at both depths, the other attributes showed average to high variability, indicating a heterogeneous environment. Thus, geostatistics emerges as an important tool in understanding the interactions in pasture ecosystems, in order to minimize possible causes of degradation and indicate better alternatives for soil-plant-animal management. The decrease in FDM and increased BD1 are indicators of physical degradation (compaction) of Red Latosol (Oxisol)...

Recovery of degraded pasture in Rondônia: macronutrients and productivity of Brachiaria brizantha.

NORONHA, N. C.; ANDRADE, C. A. de; LIMONGE, F. C.; CERRI, C. C.; CERRI, C. E. P.; PICCOLO, M. de C.; FEIGL, B. J.
Fonte: Revista Brasileira de Ciência do Solo, Viçosa, v. 34, n. 5, p. 1711-1720, 2011. Publicador: Revista Brasileira de Ciência do Solo, Viçosa, v. 34, n. 5, p. 1711-1720, 2011.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
36.39%
SUMMARY: Pasture is the main form of land use in Amazonia. Over time the pasture grass loses vigor and yields decrease, indicating a certain degree of degeneration. The main causes of degradation are lack of pasture maintenance and subsequent weed infestation, the choice of regionally unsuitable forage species and excessive grazing. The main purpose of this study was to evaluate the impact of different recovery managements on soil chemical properties and grass yield of a degraded pasture in Rondônia. For this purpose, an experiment was installed in October 2001, consisting of five treatments: C = control; HA = harrowing + NPK + micronutrients; HE = Herbicide + NK + micronutrients; R = No-tillage rice + NPK + micronutrients; and S = No-tillage soybean + PK + micronutrients. The following N, P and K sources were used: ammonium sulfate for N, calcined phosphate for P and potassium chloride for K. The experiment was arranged in a randomized block design with four replications. The shoot dry matter yield of the grass was analyzed as of the 35th month of experimentation, in a dry and a rainy period. Phosphorus fertilization resulted in significant increases in Ca2+ and Mg2+ and increasing trend of P in the topsoil in the initial months of the experiment in treatments HA and S and increases in Ca2+ and P (trend) in the treatment R. The cumulative production of Brachiaria brizantha...

Mappig and monitoring land degradation risks in the western Brazilian Amazon using multitemporal landsat TM/ETM + IMAGES.

LU, D.; BATISTELLA, M.; MAUSEL, P.; MORAN, E.
Fonte: Land Degradation & Development, v. 18, p. 41-54, 2007. Publicador: Land Degradation & Development, v. 18, p. 41-54, 2007.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
46.24%
Mapping and monitoring land degradation in areas under human-induced stresses have urgent tasks in remote sensing whose importance has not yet been fully appreciated. In this study, a surface cover index (SCI) is developed to evaluate and map potential land degradation risks associated with deforestation and accompanying soil erosion in a Western Brazilian Amazon rural settlement study area. The relationships between land-use and land-cover (LULC) types and land degradation risks as well as the impacts of LULC change on land degradation are examined. This research indicates that remotely sensed data can be effectively used for identification and mapping of land degradation risks and monitoring of land degradation changes in the study area. Sites covered by mature forest and advanced successional forests have low land degradation risk potential, while some types of initial successional forests, agroforestry/perennial agriculture and pasture have higher risk potential. Deforestation and associated soil erosion are major causes leading to land degradation, while vegetation regrowth reduces such problems.; 2007

Produtividade e composição bromatológica da Brachiaria decumbens após segundo ano de aplicação de dejetos de aves e suínos; Productivity and bromatologic attributes in Brachiaria decumbens after second year the of chicken manure application

Assis, Daniel Ferreira de
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Dissertação
POR
Relevância na Pesquisa
36.4%
CAPÍTULO 2: Entre os resíduos orgânicos produzidos pela atividade avícola, a cama de frango apresenta potencialidade para ser utilizada na recuperação de áreas degradadas. O experimento foi desenvolvido em LATOSSOLO VERMELHO distrófico sob pastagem de Brachiaria decumbens em estado de degradação objetivando avaliar a influência da fertilização com cama de frango na produtividade, atributos bromatológicos e na absorção de nutrientes da Brachiaria decumbens. O delineamento foi montado em DBC, com seis tratamentos (controle sem fertilização orgânica ou mineral, controle com fertilização mineral, quatro dosagens exclusivas de cama de frango (3.125; 6.250; 9.375 e 12.500 kg ha-1). A aplicação do resíduo foi a lanço superficial, realizaram-se duas coletas foliares, (dezembro de 2005 e fevereiro de 2006). Observou-se que a influência da aplicação sobre a produtividade ocorreu somente na segunda coleta e foi mais expressiva no tratamento com 9.375 e 12.500 kg ha-1 de cama de frango. O comportamento observado para PB, FDN, FDA e lignina foi pouco influenciado pela adubação orgânica ou mineral, esperavase que a PB fosse mais influenciada pela adubação em função do teor de nitrogênio presente na cama de frango. A absorção de nutrientes foi mais eficiente para o fósforo e o potássio...

Large-scale modeling of soil erosion with rusle for conservationist planning of degraded cultivated brazilian pastures.

GALDINO, S.; SANO, E. E.; ANDRADE, R. G.; GREGO, C. R.; NOGUEIRA, S. F.; BRAGANTINI, C.; FLOSI, A. H. G.
Fonte: Land Degradation & Development, v. 26, n. 6, p. 41-54, 2015. Publicador: Land Degradation & Development, v. 26, n. 6, p. 41-54, 2015.
Tipo: Artigo em periódico indexado (ALICE)
PT_BR
Relevância na Pesquisa
36.3%
Pasture degradation is one of the major environmental and economic problems of Brazilian livestock production. Based on the estimates of soil loss in 140,297 km2 pasturelands of Goiás State and the Federal District, the effects of land use and management and conservation practices on soil erosion by water were evaluated. Soil loss was estimated with the empirical revised universal soil loss equation model under four scenarios of land use and management of pastures and the implementation of terraces. The effects of converting hilly areas into permanently preserved areas were also evaluated. Well-managed pastures planted in terraces and highly sloped areas with native vegetation featured a reduction of 709% in the rate of soil erosion by water in comparison with poorly managed pastures without soil conservation practices. The environmental consequences of pasture degradation become particularly important when they are associated with land use in the Amazon and Cerrado biomes because farmers in these regions are forced to open new natural areas. In addition, the high indices of bare soil in degraded pastures contribute significantly to sediment deposition in rivers and dams. The modeling of soil loss is demonstrated to be an important tool for land use planning and supporting public policies focused on the sustainable use of natural resources. The results of these simulations demonstrate the importance of actions to recover degraded pastures...

Phosphorus and Defoliation Interact and Improve the Growth and Composition of the Plant Community and Soil Properties in an Alpine Pasture of Qinghai-Tibet Plateau

Qi, Juan; Nie, Zhongnan; Jiao, Ting; Zhang, Degang
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 29/10/2015 EN
Relevância na Pesquisa
36.35%
Pasture degradation caused by overgrazing and inappropriate fertiliser management is a major production and environmental threat in Qinghai-Tibet Plateau. Previous research has focused on the effects of mixed nitrogen (N) and phosphorus (P) fertiliser and reduced grazing pressure on the plant community of the grassland; however, the role of P and how it interacts with various defoliation (the process of the complete or partial removal of the above-ground parts of plants by grazing or cutting) intensities on the plant and soil of the grassland ecosystem have not been quantified. A field experiment was conducted to quantify how P application in combination of defoliation pressure could impact the dynamic change of the plant and soil in a native alpine grassland ecosystem of the Qinghai-Tibet Plateau, China, from May 2012 to September 2014. A split-plot design with 4 replicates and repeated measures was used to determine the growth and composition of plant community and soil physical and chemical properties under various levels of P fertiliser and defoliation intensity. The results showed that applying 20 kg P/ha increased the herbage yield of Melissitus ruthenica by 68% and total pasture yield by 25%. Close defoliation favoured the growth and plant frequency of the shorter species...

Reclamation status of a degraded pasture based on soil health indicators

Santos, Cristiane Alcantara dos; Krawulski, Cristina Célia; Bini, Daniel; Goulart Filho, Tadeu; Knob, Adriana; Medina, Cristiane Conti; Andrade Filho, Galdino; Nogueira, Marco Antonio
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiroz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2015 ENG
Relevância na Pesquisa
36.39%
Pasture degradation is a concern, especially in susceptible sandy soils for which strategies to recover them must be developed. Microbiological and biochemical soil health indicators are useful in the guindace of soil management practices and sustainable soil use. We assessed the success of threePanicum maximum Jacq. cultivars in the reclamation of a pasture in a sandy Typic Acrudox in the northwest of the state of Paraná, Brazil, based on soil health indicators. On a formerly degraded pasture withUrochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, a trial with threeP. maximum (cv. Massai, Tanzânia, or Mombaça) was conducted. Lime and phosphate were applied at set-up, and mineral N and K as topdressing. A remnant of degraded pasture adjacent to the trial was used as control. Twenty-three chemical, physical, microbiological and biochemical attributes were assessed for the 0-10 cm topsoil. The procedures for reclamation improved most of the indicators of soil health in relation to the degraded pasture, such as soil P, mineral N, microbial biomass C, ammonification rate, dehydrogenase activity and acid phosphatase. CO2 evolution decreased, whereas microbial biomass C increased in the pasture under reclamation, resulting in a lower metabolic quotient (qCO2) that points to a decrease in metabolic stress of the microbial community. The reclamation of the pasture withP. maximum...