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Vliv obhospodařování na diverzitu a uchycování rostlin v Krkonoších / Effect of management on the diversity and establishment of plants in the Giant MountainsTrejbalová, Lenka January 2011 (has links)
Meadows, as an integral part of the Giant Mountains, depend on regular management, without it they can get degraded. The aim of this thesis was to evaluate the impact of different types of management (mulching, mowing with or without fertilization) on change in coverage, biomass and establishment of plants. The experiment took place in years 1997-2011 on the site called Sněžné Domky in Giant Mountains on 3 sites which differ in humidity and trophy. The effect of management on vegetation change was statistically conclusive. Mulching was preffered the most by Geranium sylvaticum, mulching and fertilization was preffered especially by these species: Holcus mollis, Alopecurus pratensis and Crepis conyzifolia. Mulching and no fertilization: Achillea millefolium. Avenella flexuosa preferred particularly mowing. Mowing and fertilization was preffered by Festuca rubra, Luzula luzuloides, Anthoxanthum odoratum, Agrostis capillaris, Veronica officinalis and Hieracium lachenalii. Mowing without fertilizazion was preffered by Potentilla erecta. The effect of management on the amount of biomass appeared statistically inconclusive (except for amount of old biomass). Biomass is more correlated by the weather and the trophy of the site than the type of management. The effect of management on establishment of plant...
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Evaluation of soil erosion in the Harerge region of Ethiopia using soil loss models, rainfall simulation and field trialsBobe, Bedadi Woreka 02 August 2004 (has links)
Accelerated soil erosion is one of the major threats to agricultural production in Ethiopia and the Harerge region is not exceptional. It is estimated that about 1.5 billion tones of soil is being eroded every year in Ethiopia. In the extreme cases, especially for the highlands, the rate of soil loss is estimated to reach up to 300 t ha-1yr-1 with an average of about 70 t ha -1yr-1 which is beyond any tolerable level. The government have made different attempts to avert the situation since 1975 through initiation of a massive program of soil conservation and rehabilitation of severely degraded lands. Despite considerable efforts, the achievements were far bellow expectations. This study was aimed at assessing the effect of some soil properties, rainfall intensity and slope gradients on surface sealing, soil erodibility, runoff and soil loss from selected sites in the Harerge region, eastern Ethiopia, using simulated rainfall. Soil loss was also estimated for the sites using Soil Loss Estimation Model for Southern Africa (SLEMSA) and the Universal soil Loss Equation (USLE). Moreover, the effectiveness of various rates and patterns of wheat residue mulching in controlling soil loss was also evaluated for one of the study sites, (i.e. Regosol of Alemaya University), under both rainfall simulation and field natural rainfall conditions. For most of the erosion parameters, the interaction among soil texture, slope gradient and rainfall intensity was significant. In general however, high rainfall intensity induced high runoff, sediment yield and splash. The effect of slope gradients on most of the erosion parameters was not significant as the slope length was too small to bring about a concentrated flow. The effect of soils dominated by any one of the three soil separates on the erosion parameters was largely dependent on rainfall intensity and slope gradient. The soils form the 15 different sites in Harerge showed different degrees of vulnerability to surface sealing, runoff and sediment yield. These differences were associated with various soil properties. Correlation of soil properties to the erosion parameters revealed that aggregate stability was the main factor that determined the susceptibility of soils to sealing, runoff and soil loss. This was in turn affected by organic carbon content, percent clay and exchangeable sodium percentage (ESP). Soils with relatively high ESP such as those at Babile (13.85) and Gelemso (7.18) were among the lowest in their aggregate stability (percent water stable aggregates of 0.25 –2.0mm diameter); and have highest runoff and sediment yield as compared to other soils in the study. Similarly, most of those soils with relatively low ESP, high organic carbon content (OC%) and high water stable aggregates such as Hamaressa, AU (Alemaya University) vertisol and AU regosol were among the least susceptible to sealing and interrill erosion. Nevertheless, some exceptions include soils like those of Hirna where high runoff was recorded whilst having relatively high OC%, low ESP and high water stable aggregates. Both the SLEMSA and USLE models were able to identify the erosion hazards for the study sites. Despite the differences in the procedures of the two models, significant correlation (r = 0.87) was observed between the values estimated by the two methods. Both models estimated higher soil loss for Gelemso, Babile, Karamara and Hamaressa. Soil loss was lower for Diredawa, AU-vertisol and AU-Alluvial all of which occur on a relatively low slope gradients. The high soil loss for Babile and Gelemso conforms with the relative soil erodibility values obtained under rainfall simulation suggesting that soil erodibility, among others, is the main factor contributing to high soil loss for these soils. The difference in the estimated soil losses for the different sites was a function of the interaction of the various factors involved. Though the laboratory soil erodibility values were low to medium for Hamaressa and Karamara, the estimated soil loss was higher owing to the field topographic situations such as high slope gradient. SLEMSA and USLE showed different degrees of sensitivities to their input variables for the conditions of the study sites. SLEMSA was highly sensitive to changes in rainfall kinetic energy (E) and soil erodibility (F) and less sensitive to the cover and slope length factors. The sensitivity of SLEMSA to changes in the cover factor was higher for areas having initially smaller percentage rainfall interception values. On the other hand, USLE was highly sensitive to slope gradient and less so to slope length as compared to the other input factors. The study on the various rates and application patterns of wheat residue on runoff and soil loss both in the laboratory rainfall simulation and under field natural rainfall conditions revealed that surface application of crop residue is more effective in reducing soil loss and runoff than incorporating the same amount of the residue into the soil. Likewise, for a particular residue application method, runoff and soil loss decreased with increasing application rate of the mulch. However, the difference was not significant between 4 Mg ha-1 and 8 Mg ha-1 wheat straw rates suggesting that the former can effectively control soil loss and can be used in areas where there is limitation of crop residues provided that other conditions are similar to that of the study site (AU Regosols). The effectiveness of lower rates of straw (i.e. less than 4 Mg ha-1 ) should also be studied. It should however be noted that the effectiveness of mulching in controlling soils loss and runoff could be different under various slope gradients, rainfall characteristics and cover types that were not covered in this study. Integrated soil and water conservation research is required to develop a comprehensive database for modelling various soil erosion parameters. Further research is therefore required on the effect of soil properties (with special emphasis to aggregate stability, clay mineralogy, exchangeable cations, soil texture and organic matter), types and rates of crop residues, cropping and tillage systems, mechanical and biological soil conservation measures on soil erosion and its conservation for a better estimation of the actual soil loss in the study sites. Copyright 2004, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bobe, BW 2004, Evaluation of soil erosion in the Harerge region of Ethiopia using soil loss models, rainfall simulation and field trials, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-08022004-141533 / > / Thesis (PhD (Soil Science))--University of Pretoria, 2004. / Plant Production and Soil Science / unrestricted
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Consórcio de milho com adubos verdes e manejo da adubação nitrogenada no cultivo de feijão em sucessão no sistema integração lavoura-pecuária no cerrado / Nitrogen fertilization management in bean cultivated after maize-legumes intercropping in the Crop-Livestock Integration system in Brazilian SavannahOliveira, Priscila de 29 June 2010 (has links)
Foram realizados dez experimentos envolvendo as culturas de feijão e milho consorciado com leguminosas e/ou Brachiaria brizantha, nas safras de verão de 2008/2009, inverno de 2009 e verão de 2009/2010, em dois municípios de estado de Goiás (GO). Em Ipameri-GO, a área foi cultivada com soja por vários anos e milho consorciado com B. brizantha na safra que precedeu a implantação dos experimentos. Em Santo Antônio de Goiás-GO, a área é mantida com a rotação de milho e soja com a forrageira B. brizantha, em esquema trienal. Os principais objetivos desses estudos foram avaliar: (i) a viabilidade do consórcio de milho com leguminosas, (ii) a resposta do feijoeiro cultivado em sucessão e (iii) o manejo do N nessas culturas. Foi constatado que em solos com média a alta fertilidade química, como os utilizados na experimentação, os consórcios de milho com B. brizantha ou com guandu-anão (Canajus cajan) ou crotalária (Crotalaria spectabilis) não interferiram na produtividade de grãos de milho na presença de N em cobertura, exceto no experimento conduzido em Santo Antônio de Goiás-GO, no qual a crotalária reduziu significativamente a produtividade do milho. Também, em ambos os locais, no consórcio simultâneo ou defasado de milho com crotalária ou guandu-anão não ocorreu liberação de nitrogênio (N) das leguminosas para o milho, medido pela produtividade de grãos, durante o ciclo das espécies. Já nos consórcios em que a B. brizantha foi mantida sem dessecação nas entrelinhas do milho, denominado de dessecação parcial, ocorreu decréscimo significativo na produtividade do milho, em relação ao cultivo em área totalmente dessecada. A análise de crescimento revelou maiores índice de área foliar (IAF) e acúmulo de massa de matéria seca da parte aérea (MSPA) para o guandu em monocultivo, sendo que para a crotalária cultivada na linha do milho, tanto o IAF quanto a MSPA aproximaram-se dos valores referentes ao monocultivo. As curvas de crescimento do milho revelaram a superioridade do cultivo com 90.kg.ha-1 de N tanto no IAF quanto na MSPA, quando comparado ao cultivo consorciado com leguminosas. No caso de Santo Antônio de Goiás-GO, na rotação trienal envolvendo espécies graníferas e forrageiras, registrou-se um acentuado aporte de N no solo, sendo obtidas altas produtividades de feijão cultivado em sucessão à pastagem, sem a aplicação de N mineral, ocorrendo, porém, aumento significativo na produtividade do feijoeiro nos tratamentos de palhadas que continham leguminosas. A aplicação de N mineral imediatamente antes da semeadura ou no estádio de plântulas do feijão e do milho teve efeito semelhante nas suas produtividades em relação à aplicação tradicional, ou seja, algumas semanas após a emergência dessas espécies. A aplicação de N mineral foi mais eficiente no aumento da produtividade de feijão irrigado quando feita próximo às fileiras de plantas ou quando o N foi incorporado mecanicamente no solo, comparados à aplicação a lanço. / Ten experiments were performed involving common beans and maize intercropped with legumes and/or Brachiaria brizantha, in the summer crops of 2008/2009, 2009 winter and summer of 2009/2010 in two municipalities in the Goiás (GO) state, Brazil. In Ipameri- GO, the area was planted with soybeans for several years and corn associated with B. brizantha in crop preceding the experiments. In Santo Antônio de Goiás-GO, the area is maintained with corn or soybean rotation with B. brizantha, in a three-year scheme. The main objectives of these studies were to evaluate the feasibility of intercropping maize with legumes and the response of common bean after it, in no-tillage system, on the mulching straws provided by the cultivation of maize intercropped with forage legumes and grasses and to study the management of nitrogen (N) in these two crops. It was found that in soils with medium to high chemical fertility, such as those used in the experiments, the intercropping of corn and B. brizantha or pigeonpea (Canajus cajan) and sunn hemp (Crotalaria spectabilis) had any influence on grain yield of maize in the presence of mineral N, except in the experiment conducted in Santo Antonio de Goiás-GO, where the sunn hemp significantly reduced corn productivity. Also, in both locations, simultaneous or lagged consortium of pigeonpea or sunn hemp with maize, there was no release of N from legumes to maize, as measured by grain productivity, during the cycle of the species. However, in the consortia in which B. brizantha is maintained without drying between the maize lines, called partial desiccation, there was a significant decrease in the yield of corn in relation to the totally desiccated area. The growth analysis showed higher leaf area index (LAI) and total dry matter accumulation (TDM) for pigeonpea grown in single system, but for sunn hemp cultivated in the corn rows, both LAI and TDM approached to its single cropping, confirming its competitiveness with corn in the intercropping system. Growth curves also showed the superiority of the corn crop with 90 kg N ha-1 in both LAI and TDM, compared to intercropping with legumes. In the case of Santo Antônio de Goiás-GO the three-year rotation involving grain species and grass forages caused an intake of N in the soil, and high yields of beans grown in rotation with pasture were obtained, without the application of mineral N, occurring, though, significant increase in grain yield in the treatments of straws containing legumes. The application of mineral N immediately before sowing or at the seedling stage of beans and corn had a similar effect on their productivity compared to traditional application, a few weeks after the emergence of these species. The application of mineral N was more efficient in increasing the productivity of beans when applied on the soil surface near the plants rows and in cases where the fertilizer was mechanically incorporated into the soil, comparing to surface-broadcasting.
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Mulching Techniques for Arid Lands Vegetable ProductionPeebles, R. W., Oebker, Norman F. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / Mulches have been used for evaporation suppression in facilitating vegetable production under arid lands conditions. A study was undertaken in order to evaluate the effectiveness of plastic aprons, supplied by the FAO, as compared to gravel mulches. The vinyl aprons were 6 mils thick and about 1 meter square. Squash plants (Cucurbita pepo) were planted with gravel or plastic aprons or in bare areas and under different watering schedules. The yields under plastic aprons were considerably greater than under gravel and required slightly less water. Bare soil yields lagged far behind. Soil temperatures under the plastic aprons were consistently higher over 24 hours than bare soil, which within limits, would facilitate faster crop growth. Additionally, the apron collects and diverts rainfall to the plant. The vinyl used lasts only 2 seasons, and gravel would probably be a more suitable mulch for developing countries where capital is scarce.
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Vliv pratotechnických postupů na fytocenologické a produkční charakteristiky trvalých travních porostů / The effect of different management on plant diversity and biomass production of grass standsJÍLKOVÁ, Lucie January 2010 (has links)
The aim of this study is to assess the effect of different management practises on submontane meadow plant diversity, species richness and biomass production. The experiment was carried out in the submontane region Šumava (Kaplicko, Velký Chuchelec, Údolí Velenovského potoka). There were applied four types of management {--} continual grazing, mulching, fallow (Velký Chuchelec) and mowing (Údolí Velenovského potoka). Plant diverzity and hay production has been observing for three years. Obtained data were used for calculation Simpson and Hill index diverzity, value of fodder quality and nutritive and water regime (condition) of site. Values were used for statistical computing (ANOVA, Fischer LSD test). The plant species diverzity and biomass production are significantly affected by grassland management (treatment). Mulching and fallow lead to lower species richness and increases the coverage of grasses. Hay production is higher on mulching and fallow stands and on mowed stands than on continuously grazed stands. Mowing leads to higher species richness. Is necessary to conserve this status by mowing or the better way is to intesify contemporary management.
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Možnosti zužitkování travní hmoty. / Possible utilization of grass materialKOBERNA, Daniel January 2008 (has links)
The objective if this degree work is creating a survey of possible uses of surplus grass material which is caused by animal farming reduction and by bringing the ground in less fertile areas of our country to a standstill. In the work possible uses of the grass are described, especially its use in the energy industry as a fuel source for the production of heat and biogas. Classical usage of the grass material as a food source for livestock or for the production of compost is described here as well. Examples are shown there of energy kinds of grass, which seems to be a promising renewable resource of biomass for favourable economic results. The harvest of the grass material and its consequent prossesing is done by production lines, that is why a survey of such lines and their economic figures connected with the operation of these machines is also included in this work. The economic part of this work contains many formulae that can be used for counting out all the costs connected with the operation of the grass harvest machine and for evaluating the effectiveness of the return on investment into this machine
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Obnova druhově bohatých lučních ekosystémů na výsypkách. / Restoration of species-rich meadow ecosystems on mine spoil dumps.MATOUŠŮ, Anna January 2010 (has links)
Main object of this study was to accelerate and to direct succession in the course of a 5-year field experiment on a mine spoil dump. The effects of (1) transplanting whole meadow turfs, (2) spreading meadow soil with turfs, (3) spreading diaspore-rich mown vegetation and (4) different types of management, as possible restoration techniques are discussed in the thesis
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Consórcio de milho com adubos verdes e manejo da adubação nitrogenada no cultivo de feijão em sucessão no sistema integração lavoura-pecuária no cerrado / Nitrogen fertilization management in bean cultivated after maize-legumes intercropping in the Crop-Livestock Integration system in Brazilian SavannahPriscila de Oliveira 29 June 2010 (has links)
Foram realizados dez experimentos envolvendo as culturas de feijão e milho consorciado com leguminosas e/ou Brachiaria brizantha, nas safras de verão de 2008/2009, inverno de 2009 e verão de 2009/2010, em dois municípios de estado de Goiás (GO). Em Ipameri-GO, a área foi cultivada com soja por vários anos e milho consorciado com B. brizantha na safra que precedeu a implantação dos experimentos. Em Santo Antônio de Goiás-GO, a área é mantida com a rotação de milho e soja com a forrageira B. brizantha, em esquema trienal. Os principais objetivos desses estudos foram avaliar: (i) a viabilidade do consórcio de milho com leguminosas, (ii) a resposta do feijoeiro cultivado em sucessão e (iii) o manejo do N nessas culturas. Foi constatado que em solos com média a alta fertilidade química, como os utilizados na experimentação, os consórcios de milho com B. brizantha ou com guandu-anão (Canajus cajan) ou crotalária (Crotalaria spectabilis) não interferiram na produtividade de grãos de milho na presença de N em cobertura, exceto no experimento conduzido em Santo Antônio de Goiás-GO, no qual a crotalária reduziu significativamente a produtividade do milho. Também, em ambos os locais, no consórcio simultâneo ou defasado de milho com crotalária ou guandu-anão não ocorreu liberação de nitrogênio (N) das leguminosas para o milho, medido pela produtividade de grãos, durante o ciclo das espécies. Já nos consórcios em que a B. brizantha foi mantida sem dessecação nas entrelinhas do milho, denominado de dessecação parcial, ocorreu decréscimo significativo na produtividade do milho, em relação ao cultivo em área totalmente dessecada. A análise de crescimento revelou maiores índice de área foliar (IAF) e acúmulo de massa de matéria seca da parte aérea (MSPA) para o guandu em monocultivo, sendo que para a crotalária cultivada na linha do milho, tanto o IAF quanto a MSPA aproximaram-se dos valores referentes ao monocultivo. As curvas de crescimento do milho revelaram a superioridade do cultivo com 90.kg.ha-1 de N tanto no IAF quanto na MSPA, quando comparado ao cultivo consorciado com leguminosas. No caso de Santo Antônio de Goiás-GO, na rotação trienal envolvendo espécies graníferas e forrageiras, registrou-se um acentuado aporte de N no solo, sendo obtidas altas produtividades de feijão cultivado em sucessão à pastagem, sem a aplicação de N mineral, ocorrendo, porém, aumento significativo na produtividade do feijoeiro nos tratamentos de palhadas que continham leguminosas. A aplicação de N mineral imediatamente antes da semeadura ou no estádio de plântulas do feijão e do milho teve efeito semelhante nas suas produtividades em relação à aplicação tradicional, ou seja, algumas semanas após a emergência dessas espécies. A aplicação de N mineral foi mais eficiente no aumento da produtividade de feijão irrigado quando feita próximo às fileiras de plantas ou quando o N foi incorporado mecanicamente no solo, comparados à aplicação a lanço. / Ten experiments were performed involving common beans and maize intercropped with legumes and/or Brachiaria brizantha, in the summer crops of 2008/2009, 2009 winter and summer of 2009/2010 in two municipalities in the Goiás (GO) state, Brazil. In Ipameri- GO, the area was planted with soybeans for several years and corn associated with B. brizantha in crop preceding the experiments. In Santo Antônio de Goiás-GO, the area is maintained with corn or soybean rotation with B. brizantha, in a three-year scheme. The main objectives of these studies were to evaluate the feasibility of intercropping maize with legumes and the response of common bean after it, in no-tillage system, on the mulching straws provided by the cultivation of maize intercropped with forage legumes and grasses and to study the management of nitrogen (N) in these two crops. It was found that in soils with medium to high chemical fertility, such as those used in the experiments, the intercropping of corn and B. brizantha or pigeonpea (Canajus cajan) and sunn hemp (Crotalaria spectabilis) had any influence on grain yield of maize in the presence of mineral N, except in the experiment conducted in Santo Antonio de Goiás-GO, where the sunn hemp significantly reduced corn productivity. Also, in both locations, simultaneous or lagged consortium of pigeonpea or sunn hemp with maize, there was no release of N from legumes to maize, as measured by grain productivity, during the cycle of the species. However, in the consortia in which B. brizantha is maintained without drying between the maize lines, called partial desiccation, there was a significant decrease in the yield of corn in relation to the totally desiccated area. The growth analysis showed higher leaf area index (LAI) and total dry matter accumulation (TDM) for pigeonpea grown in single system, but for sunn hemp cultivated in the corn rows, both LAI and TDM approached to its single cropping, confirming its competitiveness with corn in the intercropping system. Growth curves also showed the superiority of the corn crop with 90 kg N ha-1 in both LAI and TDM, compared to intercropping with legumes. In the case of Santo Antônio de Goiás-GO the three-year rotation involving grain species and grass forages caused an intake of N in the soil, and high yields of beans grown in rotation with pasture were obtained, without the application of mineral N, occurring, though, significant increase in grain yield in the treatments of straws containing legumes. The application of mineral N immediately before sowing or at the seedling stage of beans and corn had a similar effect on their productivity compared to traditional application, a few weeks after the emergence of these species. The application of mineral N was more efficient in increasing the productivity of beans when applied on the soil surface near the plants rows and in cases where the fertilizer was mechanically incorporated into the soil, comparing to surface-broadcasting.
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Design automatické sekačky na trávu / Design of automatic lawnmowerRytíř, Jan January 2009 (has links)
The aim of this diploma thesis is the design of an automatic lawn mower. The design solution is based on innovative concept respecting all technical, ergonomical, aesthetical and ecological demands. A research study, including a historical, technical and design analysis of lawn mower, is preceding the description of main creative part of design process starting from the concept development and ending up with the final solution. A conclusion of the thesis presents an analysis of final solution, its character, contribution to the human society and the particular role of industial design in automatic lawn mower concept.
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Padrão sazonal da qualidade do solo, água, regimes térmicos e desempenho de culturas para biocombustíveis sob diferentes práticas de manejo / Seasonal pattern of soil quality, soil water and thermal regimes and performance of biofuel crops under different management practicesAwe, Gabriel Oladele 15 September 2014 (has links)
The intensification of biofuel production causes negative impacts on soil quality, thus the soil requires adequate assessment to ascertain its quality status, however site-specific nature of results in literature requires independent soil property measurement and assessment depending on specific agroecosystem and management goals. Therefore, the main objective of this study was to investigate seasonal pattern of soil quality, soil water and thermal regimes and performance of sugarcane and tung crops at the experimental station of Soils Department, Federal University of Santa Maria, Santa Maria, RS, Brazil. The sugarcane experiment (three seasons) was established in 2010 under no-tillage; no-tillage + compaction; conventional tillage and chiseling treatments in a randomized complete block design with three replications. In years 2011 and 2012, there was no soil disturbance; however residue mulching was imposed, giving split-plot design. The tung-based cropping system (two seasons, 2012-2014) was a randomized complete block design experiment with four replications. The treatments were: tung-crambe-sunflower/soybean + inorganic fertilizer; tung-crambe-sunflower/soybean + organic manure; tung-oats-peanut; and sole tung (control). Crambe and oats were planted in winter while sunflower (1st year)/soybean (2nd year) and peanut were planted in summer. Disturbed and undisturbed (using cores of known volume) soil samples were collected from soil layers 0-10, 10-20, 20-40 and 40-60 cm in sugarcane, and 0-10, 10-20, 20-40, 40-60 and 60-80 cm in tung for the laboratory determination of soil quality indicators. There was field monitoring of soil water retention, matric potential and soil temperature and agronomic parameters measured include sugarcane yield and tung plant height. Minimum data set for soil quality assessment was made using principal component analysis and soil quality index was obtained using weighted additive method. The temporal patterns of soil water storage and temperature were evaluated using algorithms for time series data. Except for Ma in 0-10 cm layer of tillage plots, both tillage and residue mulching did not significantly affect (p<0.05) the soil quality indicators, overall soil quality, water retention and sugarcane yield. The degree of compaction was not enough to limit sugarcane growth. Residue retention significantly influenced temporal processes of soil temperature and state-time analysis was better than classical regression of time series analysis of soil water storage and temperature. Cropping system did not significantly influence (p<0.05) soil quality indicators, overall SQI and tung plant height, but significant influenced soil water retention. For the two experiments, there was no discernible trend in the seasonal values of soil hydro-physical variables and crop response. / A intensificação da produção de biocombustíveis pode prejudicar a qualidade do solo. Portanto, para evitar a degradação do solo é necessário monitorar periodicamente os atributos mais afetados pela atividade agrícola. Assim, o objetivo deste estudo foi investigar o padrão sazonal da qualidade, da água e regimes térmicos do solo, bem como o desempenho das culturas da cana-de-açúcar e do tungue na estação experimental do Departamento de Solos da Universidade Federal de Santa Maria, Santa Maria, RS, Brasil. Para isso foram avaliados dois experimentos. O experimento de cana-de-açúcar (três anos de cultivo) foi implantado em 2010 e os tratamentos foram: plantio direto; plantio direto com compactação adicional; preparo convencional e; escarificado, distribuídos em um delineamento de blocos casualizados com três repetições. Nos anos de 2011 e 2012, não houve revolvimento do solo, mas foi adicionada cobertura vegetal morta, designando um esquema de parcelas subdivididas. Para o sistema de cultivo do tungue (dois anos de cultivo, 2012-2014) foi utilizado um experimento de blocos ao acaso com quatro repetições. Os tratamentos foram: tungue-crambe-girassol / soja com fertilizantes inorgânicos; tungue-crambe-girassol / soja com adubação orgânica; tungue-aveia-amendoim; e tungue (controle). Crambe e aveia foram plantadas no inverno, enquanto girassol (1° ano) / soja (2º ano) e amendoim foram plantados no verão. Amostras de solo com estrutura alterada e preservada foram coletadas (usando cilindros com 57 mm de diâmetro e 40 mm de altura) nas camadas de 0-10, 10-20, 20-40 e 40-60 cm na cana-de-açúcar, e de 0-10, 10-20, 20-40, 40-60 e 60-80 cm no tungue para a determinação laboratorial dos indicadores de qualidade do solo. Houve o monitoramento á campo da temperatura, umidade potencial matricial da água no solo e parâmetros agronômicos incluindo a produtividade da cana-de-açúcar e altura da planta de tungue. Um conjunto mínimo de dados para a avaliação da qualidade do solo foi obtido através da análise de componentes principais e o índice de qualidade do solo foi obtido pelo método aditivo ponderado. Os padrões temporais de armazenamento de água do solo e a temperatura do solo foram avaliados utilizando algoritmos para dados de séries temporais. Exceto para a macroporosidade, na camada de 0-10 cm dos tratamentos com preparo do solo, o preparo e a cobertura de palha não afetaram significativamente (p <0,05) os indicadores de qualidade do solo, o índice de qualidade do solo, a retenção de água ou a produtividade de cana-de-açúcar. O grau de compactação não foi suficiente para limitar o crescimento da cana-de-açúcar. A permanência da palha na superfície influenciou significativamente os processos temporais de temperatura do solo e a análise temporal foi melhor do que a análise de regressão clássica para a análise das séries temporais de armazenamento de água e temperatura do solo. O sistema de cultivo não influenciou significativamente (p<0,05) os indicadores de qualidade do solo, o índice de qualidade do solo e a altura da planta, mas influenciou significativamente a retenção de água do solo. Nos dois experimentos, não houve nenhuma tendência clara nos valores sazonais de variáveis físico-hídricas do solo e na resposta da cultura.
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