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The increasing use of plastics in rural environments has led to concerns about agricultural plastic waste (APW). However, the plasticulture information gap hinders waste management planning and may lead to plastic residue leakage into the environment with consequent microplastic formation. The location and estimated quantity of the APW are crucial for territorial planning and public policies regarding land use and waste management. Agri-plastic remote detection has attracted increased attention but requires a consensus approach, particularly for mapping plastic-mulched farmlands (PMFs) scattered across vast areas. This article tests whether a streamlined time-series approach minimizes PMF confusion with the background using less processing. Based on the literature, we performed a vast assessment of machine learning techniques and investigated the importance of features in mapping tomato PMF. We evaluated pixel-based and object-based classifications in harmonized Sentinel-2 level-2A images, added plastic indices, and compared six classifiers. The best result showed an overall accuracy of 99.7% through pixel-based using the multilayer perceptron (MLP) classifier. The 3-time series with a 30-day composite exhibited increased accuracy, a decrease in background confusion, and was a viable alternative for overcoming the impact of cloud cover on images at certain times of the year in our study area, which leads to a potentially reliable methodology for APW mapping for future studies. To our knowledge, the presented PMF map is the first for Latin America. This represents a first step toward promoting the circularity of all agricultural plastic in the region, minimizing the impacts of degradation on the environment.

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O objetivo neste trabalho foi verificar a influência da aplicação de diferentes concentrações de ácido salicílico e distintas coberturas de solo no cultivo de physalis (Physalis peruviana L). O trabalho foi desenvolvido na área experimental da Universidade Federal da Fronteira Sul, Laranjeiras do Sul-PR. Foram utilizadas mudas de physalis produzidas em casa de vegetação. A campo foram submetidas a cinco concentrações de ácido salicílico (0, 0,001, 0,002, 0,003, 0,004 Mol L-¹), e três coberturas de solo (palhada de gramínea, eucalipto e testemunha sem palhada). Nas avaliações de pré-colheita, o delineamento experimental foi de blocos ao acaso, em esquema fatorial 3x5. Para as avaliações pós-colheita o delineamento experimental foi 3x5x2, sendo considerado também o mês de colheita. Não houve interação entre os fatores para as variáveis analisadas. Para altura e diâmetro, presença de insetos, incidência e severidade de doenças foliares, somente o fator concentrações de ácido salicílico influenciou. Na pós-colheita somente o mês de colheita interferiu nos fatores, sendo a colheita de setembro com maior número e massa dos frutos, mas também o maior ataque de insetos e doenças. Concluiu-se com este trabalho que a aplicação de ácido salicílico influenciou no desenvolvimento de plantas de physalis.(AU)

The objective of this work was to verify the influence of the application of different concentrations of salicylic acid and different soil coverings in the cultivation of physalis (Physalis peruvianaL). The work was developed in the experimentalarea of the Federal University of Fronteira Sul, Laranjeiras do Sul-PR. Physalis seedlings produced in a greenhouse were used. The field was subjected to five concentrations of salicylic acid (0, 0,001, 0,002, 0,003, 0,004 Mol L-¹), and three soil coverings (grass straw, eucalyptus and control without straw). In the pre-harvest evaluations, the experimental design was randomized blocks, in a 3x5 factorial scheme. For post-harvest evaluations, the experimental design was 3x5x2, and the month of harvest was also considered. There was no interaction between the factors for the analyzed variables. For height and diameter increase and presence of insects, incidence and severity of leaf diseases, only the factor of salicylic acid influences. In the post-harvestperiod, only the month of harvest interfered in the factors, with the September harvest having the largest number and mass of fruits, but also the greatest attack by insects and diseases. It was concluded with this work that the application of salicylic acid influenced the development of physalis plants.(AU)

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Variation in rainfall affects crops; therefore, agricultural practices become essential for forage production in semi-arid regions. This study aimed to evaluate the influence of different agricultural practices on phyllochron, structural characteristics of forage cactus and millet, and their relations with crop yield using the principal component analysis (PCA). The design was in randomized blocks, with six treatments: sole cropped cactus without straw mulching, sole cropped cactus with straw mulching, sole cropped millet without straw mulching, sole cropped millet with straw mulching, and cactus intercropping with millet, with and without straw mulching, each with four replicates. There were three cactus cycles and nine millet cycles (three cycles of cultivars BRS1501 and six of IPA Bulk-1-BF). Biometric parameters were evaluated monthly, while yield was determined after the crop harvest. Phyllochron was determined with the regression analysis. The PCA was applied to structural characteristics and yield. The systems adopted did not influence the structural characteristics of cactus and millet ( p > 0.05), except for cladode thickness, which increased with straw mulching. Phyllochron of the millet reduced when the crop was intercropped. The structural characteristics of cladode length, width, and thickness influenced crop yield, mainly in systems with straw mulching. Straw mulching and intercropping alter phyllochron of cactus and millet. The adoption of straw mulching has a more significant relationship with cactus yield, whereas biometric variables influence crop yield for millet, not the cropping system.(AU)

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A cafeicultura vem crescendo cada vez mais no Brasil e, diante disso, tecnologias são desenvolvidas constantemente para obtenção de maiores produtividades. Nesse contexto, vem sendo estudado o efeito do mulching de polietileno e fontes de adubo na cafeicultura. O objetivodesse trabalho foi avaliar a incidência de bicho-mineiro e ácaro-vermelho em cafeeiro em função do uso do mulchingde polietileno e adubos (liberação controlada e convencional). A pesquisa foi realizada na área experimental da Universidade Federalde Uberlândia ­CampusMonte Carmelo, Minas Gerais, com a cultivar de Coffea arabicaIPR 100, com delineamento em blocos casualizados e quatro repetições. Foram testados os seguintes tratamentos: T1 -mulchingdupla face branco/preto com adubo convencional; T2 ­mulchingdupla face branco/preto com adubo de liberação controlada; T3 ­mulchingdupla face prata/preto com adubo convencional; T4 ­mulchingdupla face prata/preto com adubo de liberação controlada; T5 ­Sem mulchingcom adubo convencional; T6 ­Sem mulchingcom adubo de liberação controlada. As avaliações ocorreram quinzenalmente de julho de 2020 a dezembro de 2020, mediante a constatação da presença ou ausência de ácaro-vermelho e de lagartas de bicho-mineiro. Os picos de densidade populacional para bicho-mineiro ocorreram no período de julho a outubro de 2020, e para ácaro-vermelho no mês de agosto, devido à baixa umidade relativa do ar e precipitação. Assim, conclui-se que a utilização do mulchingdupla face prata/preto proporcionou maior atratividade do bicho-mineiro-do-cafeeiro. Já as fontes de adubo não influenciaram na probabilidade de ocorrência deste inseto-praga. Além disso, os adubos convencionais, bem como os de liberação controlada, e a ausência/presença de coberturas do solo, não influenciaram na incidência deácaro-vermelho em cafeeiros da região do Cerrado Mineiro.(AU)

Coffee crop has been growing increasingly in Brazil and, in view of this, technologies are constantly being developedto obtain greater productivity. In this context, the effect of polyethylene mulchingas a source of fertilizer on coffee production has been studied. The objective of this work was to evaluate the incidence of leaf miner and red mite in coffee as a function of the use of polyethylene mulching and controlled and conventional release fertilizer. The research was carried out in the experimental area of the Federal University of Uberlândia -Campus Monte Carmelo, Minas Gerais, with the cultivar IPR 100, in arandomized block design with four blocks. The following treatments were tested: T1 -double-faced white/black mulchingwith conventional fertilizer; T2 ­white/black double-sided mulchingwith controlled release fertilizer; T3 ­double-sided silver/black mulchingwith conventional fertilizer; T4 ­silver/black double-sided mulchingwith controlled release fertilizer; T5 ­No mulchingwith conventional fertilizer; T6 ­No mulchingwith controlledreleasefertilizer. The evaluations took place fortnightly from July 2020 to December 2020, upon verification of the presence or absence of leaf miner and red mite caterpillars. Population density peaks for leaf miner occurred from July to October 2020, and for red mite in August, due to low relative humidity and precipitation. Thus, it is concluded that the use of double-sided silver/black mulching provided greater attractiveness to the coffee leaf miner. The fertilizer sources did not influence the probability of occurrence of this insect pest. In addition, conventional fertilizers, as well as those of controlled release, and the absence/presence of soil coverings, did not influence the incidence of red mite in coffee trees in the Cerrado Mineiro region.(AU)

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Phthalic acid esters (PAEs) were determined in polyethylene covers used in horticultural production units located at Moreno and La Plata districts (Buenos Aires, Argentina), detecting 0.69-8.75 mg PAEs kg-1 plastic in greenhouse and tunnel films. The PAEs found were diisobutylphthalate (DIBP), dibutylphthalate (DBP) and diethylhexylphthalate (DEHP). DBP was chosen as a model molecule to carry out the photochemical degradation studies that led to the formation of monobutylphthalate (MBP) and phthalic acid (PA). DBP, MBP and PA migration from plastic covers was studied, finding that while DBP and MBP moved to soil and atmosphere in short times (<48 h), PA remained in the agricultural covers. Further experiments with DBP were made to explore the effect on migration of temperature (20 °C, 50 °C), film thickness (25 µm, 100 µm) and plastic ageing by solarization, observing that temperature increase, film thickness reduction and ageing by solarization favored DBP migration to the environment. DBP and MBP impact on soil were evaluated by avoidance and reproduction tests using Eisenia andrei as bioindicator. Both compounds reduced cocoon viability decreasing the number of juveniles at the lowest concentration assayed (0.1 mg kg-1 of soil). At higher DBP and MBP concentrations the reproductive parameters (number of total cocoons, hatchability and number of juveniles) also showed alterations compared with the controls. Carboxylesterases (CaE), cholinesterases (ChE) and glutathion-S-transferases (GST) activities were analyzed in E. andrei exposed to DBP; cholinesterases activities were reduced at 1 and 10 mg DBP kg-1 soil, and glutathione S-transferases activities were increased at 10 mg DBP kg-1 soil while no effect was observed on carboxylesterases activities. These results emphasize the need to continue studying the impact of PAEs and their photodegradation products on the environment.

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Six plots (three as controls) were established in southern Brazil to assess the reduction in runoff by vertical mulching (vm). In the other three, ditches (0.08-m wide, 0.4-m deep) were cut perpendicular to the slope, 2-m and 12-m upslope from the bottom of the plot where a flume was installed to measure runoff. Three simulated rainfalls (80 mm h-1 for 120 min, 80 mm h-1 for 65 min, 97 mm h-1 for 65 min) were applied with a sprinkler system to generate runoff. Compared to the controls, vm delayed its beginning by 10 to 20 min and reduced its volume by 34 to 39%, because initially all and later some runoff was caught in the ditches from where it infiltrated into the surrounding soil. Based on the experimental results, we derived a method to compute the runoff reduction by vm as influenced by ditch spacing (ds), initial soil moisture content (θi), and rainfall rate and duration. Computations for a combination of four ds (5 to 20 m), five θi (16 to 32%-vol), and three rainfall regimes (124 mm h-1 for 20 min, 66 mm h-1 for 60 min, and 42 mm h-1 for 120 min) showed an increasing runoff reduction as ds or θi decreased. In some cases, runoff was even completely prevented. The reductions were larger in the 60-min than in the 20-min rainfall. For the 120-min rainfall, there was no runoff with any combination of ds and θi.

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RESUMO Nas últimas décadas, têm-se observado o crescimento da demanda de água e o agravamento dos cenários de escassez hídrica, bem como a ampliação de alternativas de reuso de água de efluentes de qualidade inferior, em particular de esgotos domésticos tratados. Objetivou-se, com este trabalho, avaliar a influência do substrato de pó de coco no controle de transporte de solutos em solos irrigados com esgoto tratado doméstico. A água residuária doméstica tratada provém da Unidade Experimental de Tratamento e Reúso Hidroagrícola, no distrito de Mutuca-PE. O delineamento experimental foi em esquema fatorial (2 × 3), cujos fatores avaliados compreenderam dois tipos de solos típicos da região (Neossolo Litólico e Argissolo Amarelo) e três tratamentos (sem pó de coco, 1 cm de pó de coco e 2 cm de pó de coco), com cinco repetições. Os parâmetros de transporte dos íons sódio e potássio foram obtidos por ajuste numérico, utilizando-se o modelo STANMOD. Constatou-se a existência de interação com soluto, sódio e potássio, em solo arenoso. O modelo STANMOD apresentou ótimo desempenho na simulação do transporte de solutos no solo. A cobertura de pó de coco mostrou-se eficiente na diminuição da lixiviação de íons em ambos os solos estudados.

ABSTRACT In the last decades, there has been an increase in the demand for water and the aggravation of water scarcity scenarios, as well as the expansion of water reuse alternatives for lower quality effluents, in particular treated domestic sewage. The objective of this study was to evaluate the influence of coconut powder substrate on the control of solute transport in irrigated soils with treated sewage reuse. The treated domestic wastewater comes from the Experimental Unit for Treatment and Agricultural Reuse in the district of Mutuca, Pernambuco. The experimental design was in a factorial scheme (2 × 3), whose evaluated factors comprised two types of soils typical of the region (Leptosols and Yellow Argisol) and three treatments (no coconut powder, 1 cm coconut powder, and 2 cm coconut powder) with five replicates. The transport parameters of the sodium and potassium ions were obtained by numerical adjustment using the STANMOD model. It was found the existence of interaction with solute, sodium, and potassium in sandy soil. The STANMOD model presented excellent performance in the simulation of solute transport in the soil. Soil coverage with coconut powder was shown to be efficient in reducing leaching of ions in both studied soils.

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Banana is one of the most produced fruit crops in Brazil and has great economic, social and nutritional importance. Factors such as water availability and well-managed fertilization are fundamental to achieving profitable yields. The aim of this study was to examine the agronomic performance and water use efficiency of 'BRS Princesa' banana under combinations of irrigation systems, fertilization methods and mulching, during three production cycles. The experiment was laid out in a randomized-block design with four replicates. Treatments consisted of a combination of the localized irrigation system, fertilization strategy and mulching, as follows: Drip irrigation with manual fertilization; Micro-sprinkler irrigation with manual fertilization; Drip fertigation with mulch; Drip fertigation without mulch; Micro-sprinkler fertigation with mulch; and Microsprinkler fertigation without mulch. The plants were irrigated every three days, using three 4-L h-1 drippers per plant or a 64-L h-1 micro-sprinkler for every four plants. The following variables were analyzed: number of leaves, plant height, pseudostem circumference, number of hands, hand yield, water and nutrient (nitrogen and potassium) use efficiency and earliness. The micro-sprinkler system provided a greater pseudostem circumference without the presence of mulch. Plants under micro-sprinkler fertigation with mulching grew taller. The banana yield was higher when fertigation was used than with manual fertilization, regardless of the irrigation system. Plants grown in mulched soil were more productive than those grown in bare soil. The use of mulch increased water, nitrogen and potassium use efficiency when compared with cultivation in bare soil. Drip-irrigated plants showed earlier production than those irrigated with micro-sprinklers.(AU)

A bananeira é sendo uma das fruteiras mais produzidas no Brasil e possui grande importância econômica, social e alimentícia. Fatores como disponibilidade de água e adubação bem manejados são fundamentais para obtenção de produtividades rentáveis. Objetivou-se com este trabalho, avaliar o desempenho agronômico e a eficiência no uso da água da bananeira 'BRS Princesa' sob combinações de sistemas de irrigação, métodos de adubação e cobertura morta, durante três ciclos de produção. O delineamento experimental foi o de blocos casualizados, com quatro repetições. Os tratamentos consistiram na combinação do sistema de irrigação localizada, estratégia de adubação e uso de cobertura morta: a) Irrigação por gotejamento com adubação manual; b) Irrigação por microaspersão com adubação manual; c) Fertirrigação por gotejamento com cobertura morta; d) Fertirrigação por gotejamento sem cobertura morta; e) Fertirrigação por microaspersão com cobertura morta e f) Fertirrigação por microaspersão sem cobertura morta. As irrigações ocorreram a cada três dias, utilizando-se três gotejadores de 4 L h-1 por planta ou um microaspersor de 64 L h-1 para cada quatro plantas. As variáveis estudadas foram: número de folhas, altura da planta, perímetro do pseudocaule, número de pencas, produtividade, eficiência no uso da água e de nutrientes (nitrogênio e potássio) e precocidade. A microaspersão proporcionou maior circunferência do pseudocaule sem a presença da cobertura do solo. Plantas sob fertirrigação por microaspersão com cobertura do solo expressam maiores alturas. A produtividade da bananeira foi maior quando utilizada a fertirrigação em detrimento da adubação manual, independente do sistema de irrigação. As plantas cultivadas em solo coberto foram mais produtivas que aquelas cultivadas em solo descoberto. O uso da cobertura morta elevou a eficiência do uso da água, de nitrogênio e de potássio em relação ao cultivo em solo descoberto. As plantas irrigadas por gotejamento apresentaram produção mais precoce que irrigadas por microaspersão.(AU)

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Apesar da mandioca ser reconhecida pela sua elevada tolerância à seca, a irrigação vem apresentando resultados satisfatórios. Entretanto, poucos estudos vêm sendo desenvolvidos visando a determinação dos efeitos da cobertura do solo, da irrigação e da combinação de ambos no desenvolvimento da cultura. O objetivo deste estudo foi determinar a influência da irrigação e da cobertura plástica do solo, no desempenho agronômico de mandioca de mesa. O plantio foi feito em canteiros, no sistema de fileira dupla com as manivas-sementes implantadas na vertical em espaçamento de 0,60 m entre linhas e 0,80 m entre plantas. Foram aplicados os tratamentos canteiro desnudo sem irrigação, canteiro coberto com plástico de polietileno preto sem irrigação, canteiro desnudo com irrigação e canteiro coberto com plástico de polietileno preto com irrigação. As irrigações foram por aspersão convencional, com base no balanço diário de água do solo na profundidade efetiva do sistema radicular da mandioca nos diferentes estágios de desenvolvimento da cultura. Os caracteres avaliados em duas safras foram: produtividade de parte aérea, produtividade de raízes, porcentagem de amido nas raízes e tempo para a cocção. A expressão dos caracteres produtividade de raízes, peso da parte aérea e teor de amido nas raízes, foi influenciada pelo manejo da irrigação e pela cobertura do solo. A utilização individual das tecnologias de irrigação e de cobertura plástica do solo, proporcionaram aumentos de produtividade de raízes de 55% e 13%, respectivamente, e quando foram utilizadas em conjunto a produtividade de raízes aumentou 89%.(AU)

Although cassava is recognized for its high tolerance to drought, irrigation is showing satisfactory results. However, few studies have been carried out to determine the effects of soil cover, irrigation and the combination of both on crop development. The objective of this study was to determine the influence of irrigation and plastic soil cover on the agronomic performance of sweet cassava. The planting was done in beds, in the double row system with the stem cutings implanted vertically, with 0.60 m between rows and 0.80 m between plants. The following treatments were applied: naked non-irrigated bedding, bedding covered with non-irrigated black polyethylene plastic, naked bedding with irrigation and bedding covered with irrigated black polyethylene plastic. Irrigation was performed by conventional sprinkling, based on the daily soil water balance at the effective depth of the cassava root system in the different stages of crop development. The characters evaluated were: shoot weight, root yield, starch percentage in the roots and time for cooking. The expression of the characters shoot weight, root yield and starch percentage in the roots was significantly influenced by irrigation management and soil cover. The individual use of irrigation and plastic soil cover technologies led to increases in root yield of 55% and 13%, respectively, and when used together, root yield increased by 89%.(AU)

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Apesar da mandioca ser reconhecida pela sua elevada tolerância à seca, a irrigação vem apresentando resultados satisfatórios. Entretanto, poucos estudos vêm sendo desenvolvidos visando a determinação dos efeitos da cobertura do solo, da irrigação e da combinação de ambos no desenvolvimento da cultura. O objetivo deste estudo foi determinar a influência da irrigação e da cobertura plástica do solo, no desempenho agronômico de mandioca de mesa. O plantio foi feito em canteiros, no sistema de fileira dupla com as manivas-sementes implantadas na vertical em espaçamento de 0,60 m entre linhas e 0,80 m entre plantas. Foram aplicados os tratamentos canteiro desnudo sem irrigação, canteiro coberto com plástico de polietileno preto sem irrigação, canteiro desnudo com irrigação e canteiro coberto com plástico de polietileno preto com irrigação. As irrigações foram por aspersão convencional, com base no balanço diário de água do solo na profundidade efetiva do sistema radicular da mandioca nos diferentes estágios de desenvolvimento da cultura. Os caracteres avaliados em duas safras foram: produtividade de parte aérea, produtividade de raízes, porcentagem de amido nas raízes e tempo para a cocção. A expressão dos caracteres produtividade de raízes, peso da parte aérea e teor de amido nas raízes, foi influenciada pelo manejo da irrigação e pela cobertura do solo. A utilização individual das tecnologias de irrigação e de cobertura plástica do solo, proporcionaram aumentos de produtividade de raízes de 55% e 13%, respectivamente, e quando foram utilizadas em conjunto a produtividade de raízes aumentou 89%.

Although cassava is recognized for its high tolerance to drought, irrigation is showing satisfactory results. However, few studies have been carried out to determine the effects of soil cover, irrigation and the combination of both on crop development. The objective of this study was to determine the influence of irrigation and plastic soil cover on the agronomic performance of sweet cassava. The planting was done in beds, in the double row system with the stem cutings implanted vertically, with 0.60 m between rows and 0.80 m between plants. The following treatments were applied: naked non-irrigated bedding, bedding covered with non-irrigated black polyethylene plastic, naked bedding with irrigation and bedding covered with irrigated black polyethylene plastic. Irrigation was performed by conventional sprinkling, based on the daily soil water balance at the effective depth of the cassava root system in the different stages of crop development. The characters evaluated were: shoot weight, root yield, starch percentage in the roots and time for cooking. The expression of the characters shoot weight, root yield and starch percentage in the roots was significantly influenced by irrigation management and soil cover. The individual use of irrigation and plastic soil cover technologies led to increases in root yield of 55% and 13%, respectively, and when used together, root yield increased by 89%.

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Biodegradable films are a promising strategy to reduce the environmental impact caused by conventional plastics commonly used in agriculture. This study focused on the production and characterization of Konjac glucomannan (KGM) and alginate (ALG) based films enriched with sugarcane vinasse (VIN), a nutrient-rich wastewater generated in large volumes by the sugar-ethanol producing industries. ALG, KGM and ALG/KGM blended (50:50) films were produced by casting and treated with calcium ions (Ca2+) (ALG films) and a combination of Ca2+, alkali, and ethanol (KGM and ALG/KGM films). Vinasse addition tended to reduce transparency and water resistance of the films and had less effect on their mechanical properties. Crosslinking of ALG films resulted in enhanced mechanical properties and reduced moisture content, water solubility, swelling, water vapor permeability, and flexibility. KGM films were less impacted by crosslinking/deacetylation but showed improved water resistance while maintain a high degree of swelling (290% and 185% for KGM and KGM/VIN films respectively). Blended films exhibited characteristic properties of the two biopolymers and adequate compatibility indicated by Fourier transform infrared spectroscopy (FTIR) and morphologies. Vinasse-added ALG/KGM films represent a novel nutrient-enriched, bio-based material for agricultural applications and could help to face the environmental challenges imposed by vinasse disposal.

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RESUMO A região semiárida do nordeste brasileiro é marcada por elevadas incertezas quanto à ocorrência de chuvas intensas, bem como por anos sequenciados de secas. Esses fenômenos naturais, somados à reduzida utilização de práticas conservacionistas, podem gerar degradação dos solos. Nesse contexto, o presente estudo objetivou avaliar a importância do uso de cobertura morta e espécies de oleaginosas não convencionais perenes (Moringa oleifera Lam. e Azadirachta indica A. Juss.) no controle da erosão do solo em parcelas de erosão, em condições de chuvas naturais. O estudo realizou-se durante os anos de 2016 e 2017 na bacia representativa do Mimoso, localizada no município de Pesqueira (PE), Brasil. Na área de estudo, instalaram-se três parcelas de erosão, cada uma com área igual a 40 m2 (2 × 20 m), que foram intensamente monitoradas no tocante à intensidade de precipitação, à umidade e à temperatura do solo, ao escoamento superficial e à produção de sedimentos. Para cada parcela experimental, adotaram-se os seguintes tratamentos: oleaginosas; oleaginosas + cobertura morta; solo descoberto. A cobertura do solo com oleaginosas e cobertura morta resultou em maior retenção de umidade do solo e menores valores de escoamento superficial e perdas de solo. O desenvolvimento da estrutura das oleaginosas diminuiu o impacto direto das gotas de chuva no solo, reduzindo as perdas de solo quando comparadas ao descoberto.

ABSTRACT The semiarid region of the Brazilian Northeast is marked by strong uncertainties regarding the occurrence of extreme rainfall, as well as the occurrence of sequenced year droughts. These natural phenomena, together with limited use of soil and water conservation practices, can generate soil degradation. In this context, the present study aimed to evaluate the importance of the use of mulch and non-conventional perennial oleaginous species (Moringa oleifera Lam. and Azadirachta indica A. Juss.) in soil erosion plots under natural rainfall. The study was conducted during the years of 2016 and 2017 in the representative basin of Mimoso, located in the municipality of Pesqueira, Pernambuco, Brazil. Three erosion plots each with an area of 40 m2 (2 m × 20 m), were installed in the study area, which were intensively monitored for rainfall intensity, soil moisture and temperature, runoff and sediment production. For each experimental plot, the following treatments were adopted: Oleaginous; Oleaginous + mulch; Bare soil. Soil cover with oleaginous species and mulch resulted in higher soil moisture and lower amounts of runoff and soil loss. The development of the tree structure of the oleaginous reduced the direct impact of raindrops on the soil surface, reducing the soil losses when compared to the bare soil.

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Mechanical harvesting leaves in its wake a considerable amount of straw in the field, which can be effectively utilized to improve the soil condition and sugarcane yield. However, there is no specific information as to the quantity of straw mulch required to achieve such effects and as to whether it can be used in other sectors for bioelectricity and ethanol production. The aim of this research was to evaluate the effect of removing different amounts of straw from the field and its impact on the yield and industrial quality of sugarcane ratoons. The experiment was carried out on Rhodic soil where six treatments were evaluated including 0 %, 25 % (5 Mg ha1), 50 % (10 Mg ha1), 75 % (15 Mg ha1), 100 % (20 Mg ha1) straw on the soil surface and burned sugarcane (where 100 % of the straw was burned). The influence on yield and industrial quality was calculated using total soluble solids, Pol (Apparent sucrose content), apparent purity, total sugars, reducing sugars and fiber. Shifting the harvesting system from burned cane to growing under straw mulch improved crop yield as well as favoring sugar contents during water deficit conditions. The straw left on the soil did not affect industrial quality in any way during the trials; however, under drought conditions, treatments with 50 and 75 % of straw resulted in a 76 % higher yield compared to burned sugarcane, and 29 % more than the 0 %, 25 % to 100 % treatments of straw mulch thus favoring higher sugar production. The removal of 50 % of the straw caused no damage to the sugarcane crop.(AU)

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ABSTRACT: Mechanical harvesting leaves in its wake a considerable amount of straw in the field, which can be effectively utilized to improve the soil condition and sugarcane yield. However, there is no specific information as to the quantity of straw mulch required to achieve such effects and as to whether it can be used in other sectors for bioelectricity and ethanol production. The aim of this research was to evaluate the effect of removing different amounts of straw from the field and its impact on the yield and industrial quality of sugarcane ratoons. The experiment was carried out on Rhodic soil where six treatments were evaluated including 0 %, 25 % (5 Mg ha1), 50 % (10 Mg ha1), 75 % (15 Mg ha1), 100 % (20 Mg ha1) straw on the soil surface and burned sugarcane (where 100 % of the straw was burned). The influence on yield and industrial quality was calculated using total soluble solids, Pol (Apparent sucrose content), apparent purity, total sugars, reducing sugars and fiber. Shifting the harvesting system from burned cane to growing under straw mulch improved crop yield as well as favoring sugar contents during water deficit conditions. The straw left on the soil did not affect industrial quality in any way during the trials; however, under drought conditions, treatments with 50 and 75 % of straw resulted in a 76 % higher yield compared to burned sugarcane, and 29 % more than the 0 %, 25 % to 100 % treatments of straw mulch thus favoring higher sugar production. The removal of 50 % of the straw caused no damage to the sugarcane crop.

RESUMO

ABSTRACT: Mechanical harvesting leaves in its wake a considerable amount of straw in the field, which can be effectively utilized to improve the soil condition and sugarcane yield. However, there is no specific information as to the quantity of straw mulch required to achieve such effects and as to whether it can be used in other sectors for bioelectricity and ethanol production. The aim of this research was to evaluate the effect of removing different amounts of straw from the field and its impact on the yield and industrial quality of sugarcane ratoons. The experiment was carried out on Rhodic soil where six treatments were evaluated including 0 %, 25 % (5 Mg ha1), 50 % (10 Mg ha1), 75 % (15 Mg ha1), 100 % (20 Mg ha1) straw on the soil surface and burned sugarcane (where 100 % of the straw was burned). The influence on yield and industrial quality was calculated using total soluble solids, Pol (Apparent sucrose content), apparent purity, total sugars, reducing sugars and fiber. Shifting the harvesting system from burned cane to growing under straw mulch improved crop yield as well as favoring sugar contents during water deficit conditions. The straw left on the soil did not affect industrial quality in any way during the trials; however, under drought conditions, treatments with 50 and 75 % of straw resulted in a 76 % higher yield compared to burned sugarcane, and 29 % more than the 0 %, 25 % to 100 % treatments of straw mulch thus favoring higher sugar production. The removal of 50 % of the straw caused no damage to the sugarcane crop.

RESUMO

The objective was to evaluate strawberry productivity under different soil cover, as well as its effectiveness on the weed control in an organic production system. The experiment was conducted in the Universidade Federal da Fronteira Sul - UFFS, campus Cerro Largo. The random blocks delineation with 6 blocks was used. The units were designed using 10 aromas cultivar plants, planted in 4 interspersed lines each 0,3m apart. The treatments used were whole plants of Sudan grass (Sorghum sudanense), shavings, acicula of Pinus (Pinus elliottii), black polyethylene and uncovered soil. To determine the productive aspects, the mass production, number and size of fruit were evaluated. The effectiveness of the weed control under different soil cover was determined through the dry weed mass collected monthly. With the exception of the sudan grass, all the other treatments statistically matched the productive aspects. The black polyethylene cover presented better weed control.

Este trabalho teve o objetivo de avaliar a produtividade do morangueiro em função de diferentes coberturas de solo e a efetividade destas sobre o controle de plantas daninhas, em sistema orgânico de produção. O experimento foi conduzido em área da Universidade Federal da Fronteira Sul - UFFS, Campus Cerro Largo. Utilizou-se delineamento de blocos ao acaso com seis blocos. Cada parcela foi constituída por dez plantas da cultivar Aromas, dispostas em quatro linhas intercaladas, distanciadas em 0,30 metros. Os tratamentos utilizados foram plantas inteiras de Capim Sudão (Sorghum sudanense), maravalha, acícula de pinus (Pinus elliottii), polietileno preto e solo descoberto. Para a determinação dos aspectos produtivos foram avaliadas a produtividade em massa, o número e o tamanho dos pseudofrutos. A efetividade de controle das plantas daninhas pelas diferentes coberturas foi determinada através da massa seca das plantas coletadas mensalmente. Com exceção da cobertura com Capim Sudão, todos os demais tratamentos se equiparam, estatisticamente, nos aspectos produtivos. A cobertura com polietileno preto apresentou maior controle sobre plantas daninhas.

Assuntos

RESUMO

The objective was to evaluate strawberry productivity under different soil cover, as well as its effectiveness on the weed control in an organic production system. The experiment was conducted in the Universidade Federal da Fronteira Sul - UFFS, campus Cerro Largo. The random blocks delineation with 6 blocks was used. The units were designed using 10 aromas cultivar plants, planted in 4 interspersed lines each 0,3m apart. The treatments used were whole plants of Sudan grass (Sorghum sudanense), shavings, acicula of Pinus (Pinus elliottii), black polyethylene and uncovered soil. To determine the productive aspects, the mass production, number and size of fruit were evaluated. The effectiveness of the weed control under different soil cover was determined through the dry weed mass collected monthly. With the exception of the sudan grass, all the other treatments statistically matched the productive aspects. The black polyethylene cover presented better weed control.(AU)

Este trabalho teve o objetivo de avaliar a produtividade do morangueiro em função de diferentes coberturas de solo e a efetividade destas sobre o controle de plantas daninhas, em sistema orgânico de produção. O experimento foi conduzido em área da Universidade Federal da Fronteira Sul - UFFS, Campus Cerro Largo. Utilizou-se delineamento de blocos ao acaso com seis blocos. Cada parcela foi constituída por dez plantas da cultivar Aromas, dispostas em quatro linhas intercaladas, distanciadas em 0,30 metros. Os tratamentos utilizados foram plantas inteiras de Capim Sudão (Sorghum sudanense), maravalha, acícula de pinus (Pinus elliottii), polietileno preto e solo descoberto. Para a determinação dos aspectos produtivos foram avaliadas a produtividade em massa, o número e o tamanho dos pseudofrutos. A efetividade de controle das plantas daninhas pelas diferentes coberturas foi determinada através da massa seca das plantas coletadas mensalmente. Com exceção da cobertura com Capim Sudão, todos os demais tratamentos se equiparam, estatisticamente, nos aspectos produtivos. A cobertura com polietileno preto apresentou maior controle sobre plantas daninhas.(AU)

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Horticulture makes intensive use of soil and extensive use of polyethylene (PE) sheeting and pesticides, producing an environment where the dynamics between soil and plastics can affect pesticide fate. We have determined that the presence of plastic residues in the horticultural soil of small production units equals 10% of the soil area, being meso and macro-sections the predominant fragment sizes. All soil samples were taken from different plots located in Cuartel V, Moreno district, in the suburbs of Buenos Aires city, Argentina. Laboratory experiments were conducted to see the relations among pesticide, soil and PE film. Endosulfan recovery from LDPE films (25µm and 100µm) was studied, observing evidence that indicated migration to the inside of the plastic matrix. To further analyze the dynamics of pesticide migration to soil and atmosphere, experiments using chlorpyrifos, procymidone and trifluralin were performed in soil-plastic-atmosphere microenvironments, showing that up to 24h significant amounts of pesticides moved away from the PE film. To determine whether PE residues could act as potential pesticide collector in soil, column elution experiments were done using chlorpyrifos, procymidone and trifluralin. Results showed an important pesticide accumulation in the mulch film (584µg-2284µg pesticide/g plastic) compared to soil (13µg-32µg pesticide/g soil). Finally, chemical and photochemical degradation of deltamethrin adsorbed in PE film was studied, finding a protective effect on hydrolysis but no protective effect on photodegradation. We believe that a deeper understanding of the dynamics among soil, plastic and pesticides in horticultural productive systems may contribute to alert for the implications of PE use for plastic sheeting.

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O objetivo deste trabalho foi avaliar a produção de massa, teores e aporte foliares de adubos verdes, utilizados em região de altitude do Espírito Santo, adequados à implantação da prática de plantio direto de hortaliças sob manejo orgânico. Objetivou-se também avaliar a evolução da fertilidade do solo em decorrência de dois pré-cultivos de milho e crotalária (fevereiro 2009 e outubro 2009) e dois pré-cultivos de aveia preta e tremoço branco (julho de 2010 e maio de 2011). Este trabalho foi desenvolvido na Unidade de Referência em Agroecologia do INCAPER, em Domingos Martins-ES. Os tratamentos consistiram de uma testemunha (sem palhada) e três sistemas de produção de palhadas: 1) cultivo solteiro de gramíneas (milho ou aveia preta); 2) cultivo solteiro de leguminosas (crotalária ou tremoço branco) e 3) cultivo consorciado de gramíneas/leguminosas (milho/crotalária ou aveia/tremoço). Em fevereiro de 2009, a produção de massa verde do sistema milho e milho/crotalária atingiram 73,6 e 64,5 t ha-1, respectivamente. Em julho de 2010, a produção de massa verde nos sistemas tremoço e consórcio aveia/tremoço atingiram 76,3 e 88,3 t ha-1, respectivamente. Os adubos verdes em consórcio comprovaram ser excelente opção de manejo para sistemas orgânicos, por aportarem ao solo 811,4; 941,2; 263,5; 78,6; 51,9 kg ha-1 de N, K, Ca, Mg e S, respectivamente, valores estes iguais ou superiores aos pré-cultivos solteiros. Os efeitos dos pré-cultivos de adubos verdes sobre os atributos químicos do solo em manejo orgânico, excetuando-se o aporte de nitrogênio, foram semelhantes à testemunha em todas as épocas, possivelmente nivelados pela adubação de base com composto orgânico em todos os tratamentos, que mantém altos índices de fertilidade da área.

The aim of this study was to evaluate mass production, nutrient contents and input of green manures used in the altitude region of Espírito Santo to the implementation of appropriate practice no tillage vegetables under organic management. This study also aimed evaluate the evolution of soil fertility as a consequence of two pre-crop maize and crotalária (February 2009 and October 2009) and two pre-crop oat and white lupine (July 2010 and May 2011). The experiments were carried in the INCAPER's Agroecology Reference Area at Domingos Martins-ES. Treatments consisted of a control (no straw) and three straw production systems: 1) cropping of grasses (oats or corn), 2) cropping legume (crotalária or white lupine) and 3) intercropping of grasses/legumes (corn/crotalária or oat/lupine). In February 2009, the production of green mass system corn and corn/crotalária reached 73.6 and 64.5 t ha-1, respectively. In July 2010, the production of green mass systems lupine and oat/Lupin reached 76.3 and 88.3 t ha-1, respectively. The green manures intercropping proved to be excellent management option for organic systems, because added 811.4; 941.2; 263.5; 78.6; 51.9 kg ha-1 of N, K, Ca, Mg and S, respectively, values those at or above the single pre-cultivation. The effects of pre-cultivation of green manure on soil chemical properties in organic management, except for the contribution of nitrogen, were similar to control in all seasons, because of the base fertilization with organic compost in all treatments, maintaining high fertility rates in the area.

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