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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sistemas de manejo conservacionista do solo para cultivares de amendoim em sucessão à cana crua e pastagens

Bolonhezi, Denizart [UNESP] 18 January 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-18Bitstream added on 2014-06-13T21:06:48Z : No. of bitstreams: 1 bolonhezi_d_dr_jabo.pdf: 3253229 bytes, checksum: 974742cfe4f4b872d8710f3c2803a997 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Apta / No estado de São Paulo, o amendoim é cultivado principalmente na sucessão à cana-de-açúcar e pastagem, em duas regiões distintas quanto às condições edafoclimáticas. Atualmente, devido ao aumento das áreas com canaviais colhidos sem queima e dos sistemas de integração agricultura e pecuária, os produtores têm a oportunidade de adotarem manejos de solo conservacionistas. Considerando as peculiaridades morfo-fisiológicas da planta de amendoim, os objetivos desta pesquisa foram : estudar as características agronômicas e extração de nutrientes de duas cultivares de amendoim com hábitos de crescimento contrastantes em três manejos de solo sobre palhada de cana crua e pastagem, bem como avaliar os efeitos desses sistemas sobre alguns atributos químicos, físicos e microbiológicos do solo. Foram instalados 12 experimentos de campo, conduzidos de 1999/2000 até 2004/2005, na áreas experimentais da APTA (antigas estações do IAC e IZ), sendo 9 em Latossolo vermelho (Ribeirão Preto, 6 em cana crua e 3 em pastagem) e 3 em Argissolos, dos quais 2 (pastagem e cana crua) em Pindorama e 1 (pastagem) em Mirassol. Em delineamento experimental blocos casualizados os tratamentos foram arranjados em esquema de parcelas subdivididas, utilizando-se 4 repetições. As parcelas compreenderam os sistemas de manejo convencional (arado de aivecas + gradagens), cultivo mínimo (5 L.ha-1de glifosate + arado subsolador ASTMATIC 450®, Tatu Marchesan) e plantio direto (5 L.ha-1de glifosate). As sub-parcelas foram constituídas pelas cultivares IAC-Tatu ST (ereta) e IAC-Caiapó (rasteira)... / In Sao Paulo State, Brazil, peanut has been cultivated in rotation with sugarcane and pasture in two regions with different soil type and climate conditions. Nowadays, due to the increase of sugarcane area harvested without burning and the crop-livestock integration systems, the peanut growers have a great opportunity to plant in the conservation tillage, mainly in no-tillage system. Considering the specific morphological and physiological characteristic of peanut plant, the aims of this research were to study the agronomic characteristics and nutrient contents of two different peanut cultivars in three tillage systems in rotation with sugarcane and pasture, as well as their effects in some chemical, physical and microbiological soil attributes. Twelve field experiments were conducted from 1999/2000 to 2004/2005, at the followings places: Ribeirão Preto (Oxisoil), Pindorama (Ultisoil) and Mirassol (Ultisoil). Seven trials were installed on sugarcane straw and five in rotation with pasture, which were situated at APTA experimental station. Tillage treatments were arranged in split-plot randomized complete block design with four replications. The main plots were the tillage treatments (conventional, reduced and no-tillage) while the subplots were peanut cultivars (IACTatu ST and IAC-Caiapó). In the conventional tillage, soil was turned with a moldboard plow and disked. Reduced tillage was made with subsoiler shank (ASTMATIC 450 , Tatu Marchesan) after the herbicide application. In no-tillage systems, the sugarcane plant and pasture were killed with glyphosate (2.4 kg a.i.ha-1). Some agronomic characteristics (pod and kernels yield, percentage of sound mature kernels, plant density and dry matter of root in different layers), nodulation (number and dry matter) and nutrient contents (N,P, K, Ca, Mg, S, Cu, Mn, Zn) in plants were evaluated...(Complete abstract, acess undermentioned eletronic adress)
2

Sistemas de manejo conservacionista do solo para cultivares de amendoim em sucessão à cana crua e pastagens /

Bolonhezi, Denizart. January 2007 (has links)
Orientador: Miguel Angelo Mutton / Banca: Ignácio José de Godoy / Banca: Edson Lazarini. / Banca: José Frederico Centurion / Banca: Gil Miguel de Sousa Centurion / Resumo: No estado de São Paulo, o amendoim é cultivado principalmente na sucessão à cana-de-açúcar e pastagem, em duas regiões distintas quanto às condições edafoclimáticas. Atualmente, devido ao aumento das áreas com canaviais colhidos sem queima e dos sistemas de integração agricultura e pecuária, os produtores têm a oportunidade de adotarem manejos de solo conservacionistas. Considerando as peculiaridades morfo-fisiológicas da planta de amendoim, os objetivos desta pesquisa foram : estudar as características agronômicas e extração de nutrientes de duas cultivares de amendoim com hábitos de crescimento contrastantes em três manejos de solo sobre palhada de cana crua e pastagem, bem como avaliar os efeitos desses sistemas sobre alguns atributos químicos, físicos e microbiológicos do solo. Foram instalados 12 experimentos de campo, conduzidos de 1999/2000 até 2004/2005, na áreas experimentais da APTA (antigas estações do IAC e IZ), sendo 9 em Latossolo vermelho (Ribeirão Preto, 6 em cana crua e 3 em pastagem) e 3 em Argissolos, dos quais 2 (pastagem e cana crua) em Pindorama e 1 (pastagem) em Mirassol. Em delineamento experimental blocos casualizados os tratamentos foram arranjados em esquema de parcelas subdivididas, utilizando-se 4 repetições. As parcelas compreenderam os sistemas de manejo convencional (arado de aivecas + gradagens), cultivo mínimo (5 L.ha-1de glifosate + arado subsolador ASTMATIC 450®, Tatu Marchesan) e plantio direto (5 L.ha-1de glifosate). As sub-parcelas foram constituídas pelas cultivares IAC-Tatu ST (ereta) e IAC-Caiapó (rasteira)...(Resumo completo, clicar no acesso eletrônico abaixo) / Abstract: In Sao Paulo State, Brazil, peanut has been cultivated in rotation with sugarcane and pasture in two regions with different soil type and climate conditions. Nowadays, due to the increase of sugarcane area harvested without burning and the crop-livestock integration systems, the peanut growers have a great opportunity to plant in the conservation tillage, mainly in no-tillage system. Considering the specific morphological and physiological characteristic of peanut plant, the aims of this research were to study the agronomic characteristics and nutrient contents of two different peanut cultivars in three tillage systems in rotation with sugarcane and pasture, as well as their effects in some chemical, physical and microbiological soil attributes. Twelve field experiments were conducted from 1999/2000 to 2004/2005, at the followings places: Ribeirão Preto (Oxisoil), Pindorama (Ultisoil) and Mirassol (Ultisoil). Seven trials were installed on sugarcane straw and five in rotation with pasture, which were situated at APTA experimental station. Tillage treatments were arranged in split-plot randomized complete block design with four replications. The main plots were the tillage treatments (conventional, reduced and no-tillage) while the subplots were peanut cultivars (IACTatu ST and IAC-Caiapó). In the conventional tillage, soil was turned with a moldboard plow and disked. Reduced tillage was made with subsoiler shank (ASTMATIC 450 , Tatu Marchesan) after the herbicide application. In no-tillage systems, the sugarcane plant and pasture were killed with glyphosate (2.4 kg a.i.ha-1). Some agronomic characteristics (pod and kernels yield, percentage of sound mature kernels, plant density and dry matter of root in different layers), nodulation (number and dry matter) and nutrient contents (N,P, K, Ca, Mg, S, Cu, Mn, Zn) in plants were evaluated...(Complete abstract, acess undermentioned eletronic adress) / Doutor
3

Preliminary investigation of nutrient contents in wastewater at some coastal communes of Giao Thuy district, Nam Dinh province

Le, Nhu Da, Le, Thi Phuong Quynh, Duong, Thi Thuy 07 February 2019 (has links)
Wastewater, especially non-treated wastewater from different sources is one of causes for surface and ground water pollution. However, the monitoring of wastewater quality has not been regularly implemented. This paper presents the preliminary observation results of the wastewater quality of different sources such as domestic, fishery processing, husbandry, agricultural runoff and irrigation canals in some coastal communes of Giao Thuy district, Nam Dinh province in 2017 - 2018. The results showed variation values of some variables as following: pH: 3.4 to 8.7; DO: 1.1 – 7.6 mg/l; conductivity: 0.01 – > 99.9 S/m; Suspended solids: 7 – 599 mg.L-1; nitrate (NO3-): 0.01-1.74 mgL-1; ammonium (NH4+): 0.01 - 3.99 mgNL-1, phosphate (PO43-): < 0.01– 3.05 mgPL-1, total phosphorus: 0.01 – 5.03 mgPL-1. The values of some variables such as DO, pH, nitrite, ammonium, suspended solids and phosphate at some observation time exceeded the allowed values of the Vietnamese standards for domestic wastewater quality, for industrial wastewater quality and for surface water quality. Among these different wastewaters observed, the higher contents of nutrients were found for domestic wastewater. The results provide a dataset for environmental managers in order to control of wastewater quality, especially for the coastal communes where coastal aquacultural areas are large like Giao Thuy district, Nam Dinh province. / Nước thải, đặc biệt là nước thải chưa qua xử lý từ nhiều nguồn thải khác nhau là một trong những nguyên nhân gây ô nhiễm nguồn nước mặt và nước ngầm. Tuy nhiên việc giám sát chất lượng nước, lại chưa được thường xuyên thực hiện. Bài báo trình bày kết quả khảo sát bước đầu về chất lượng nước thải sinh hoạt, chế biến thủy sản, chăn nuôi, nông nghiệp, kênh dẫn tưới tiêu tại một số xã ven biển thuộc huyện Giao Thủy, tỉnh Nam Định trong năm 2017 - 2018. Kết quả khảo sát cho thấy khoảng giá trị của một số thông số như sau: pH 3,4 – 8,7; DO: 1,1 – 7,6 mgL-1; độ dẫn điện: 0,01 – 99,9 S/m; chất rắn lơ lửng: 7 – 599 mg.L-1; nitrat (NO3-): 0.01-1.74 mgL-1; amoni (NH4+): 0.01 - 3.99 mgNL-1; phốtphat (PO43-): <0,01 - 3,05 mgPL-1 và phốtpho tổng số: 0,01 – 5,03 mgL-1. Hàm lượng một số chỉ tiêu như NO2, NH4 +, PO43-, SS tại một số thời điểm đã vượt quá giá trị cho phép theo các quy chuẩn nước thải sinh hoạt, nước thải công nghiệp và nước tưới tiêu. Trong các loại nước thải đã quan trắc, nước thải sinh hoạt có hàm lượng các chỉ tiêu dinh dưỡng cao hơn. Các kết quả nghiên cứu nhằm cung cấp cơ sở dữ liệu cho các nhà quản lý về việc kiểm soát chất lượng nước thải, đặc biệt là các xã ven biển có diện tích nuôi trồng thủy sản khá lớn như huyện Giao Thủy, tỉnh Nam Định.
4

Estimation of Nutrient Exports Resulting from Thinning and Intensive Biomass Extraction in Medium-Aged Spruce and Pine Stands in Saxony, Northeast Germany.

Knust, Christine, Feger, Karl-Heinz 27 March 2017 (has links) (PDF)
A growing interest in using forest biomass for bioenergy generation may stimulate intensive harvesting scenarios in Germany. We calculated and compared nutrient exports of conventional stem only (SO), whole tree without needles (WT excl. needles), and whole tree (WT) harvesting in two medium aged Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.) stands differing in productivity, and related them to soil nutrient pools and fluxes at the study sites. We established allometric biomass functions for each aboveground tree compartment and analyzed their nutrient contents. We analyzed soil nutrient stocks, estimated weathering rates, and obtained deposition and seepage data from nearby Level II stations. WT (excl. needles) and WT treatments cause nutrient losses 1.5 to 3.6 times higher than SO, while the biomass gain is only 1.18 to 1.25 in case of WT (excl. needles) and 1.28 to 1.30 in case of WT in the pine and spruce stand, respectively. Within the investigated 25-year period, WT harvesting would cause exports of N, K+, Ca2+, and Mg2+ of 6.6, 8.8, 5.4, and 0.8 kg·ha−1 in the pine stand and 13.9, 7.0, 10.6, and 1.8 kg·ha−1 in the spruce stand annually. The relative impact of WT and WT (excl. needles) on the nutrient balance is similar in the pine and spruce stands, despite differences in stand productivities, and thus the absolute amount of nutrients removed. In addition to the impact of intensive harvesting, both sites are characterized by high seepage losses of base cations, further impairing the nutrient budget. While intensive biomass extraction causes detrimental effects on many key soil ecological properties, our calculations may serve to implement measures to improve the nutrient balance in forested ecosystems.
5

Estimation of Nutrient Exports Resulting from Thinning and Intensive Biomass Extraction in Medium-Aged Spruce and Pine Stands in Saxony, Northeast Germany.

Knust, Christine, Feger, Karl-Heinz 27 March 2017 (has links)
A growing interest in using forest biomass for bioenergy generation may stimulate intensive harvesting scenarios in Germany. We calculated and compared nutrient exports of conventional stem only (SO), whole tree without needles (WT excl. needles), and whole tree (WT) harvesting in two medium aged Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.) stands differing in productivity, and related them to soil nutrient pools and fluxes at the study sites. We established allometric biomass functions for each aboveground tree compartment and analyzed their nutrient contents. We analyzed soil nutrient stocks, estimated weathering rates, and obtained deposition and seepage data from nearby Level II stations. WT (excl. needles) and WT treatments cause nutrient losses 1.5 to 3.6 times higher than SO, while the biomass gain is only 1.18 to 1.25 in case of WT (excl. needles) and 1.28 to 1.30 in case of WT in the pine and spruce stand, respectively. Within the investigated 25-year period, WT harvesting would cause exports of N, K+, Ca2+, and Mg2+ of 6.6, 8.8, 5.4, and 0.8 kg·ha−1 in the pine stand and 13.9, 7.0, 10.6, and 1.8 kg·ha−1 in the spruce stand annually. The relative impact of WT and WT (excl. needles) on the nutrient balance is similar in the pine and spruce stands, despite differences in stand productivities, and thus the absolute amount of nutrients removed. In addition to the impact of intensive harvesting, both sites are characterized by high seepage losses of base cations, further impairing the nutrient budget. While intensive biomass extraction causes detrimental effects on many key soil ecological properties, our calculations may serve to implement measures to improve the nutrient balance in forested ecosystems.

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