Soil loss by water erosion in areas under maize and jack beans intercropped and monocultures

Adequate soil management can create favorable conditions to reduce erosion and water runoff, consequently increase water soil recharge. Among management systems intercropping is highly used, especially for medium and small farmers. It is a system where two or more crops with different architectures and vegetative cycles are explored simultaneously at the same location. This research investigated the effects of maize intercropped with jack bean on soil losses due to water erosion, estimate C factor of Universal Soil Losses Equation (USLE) and how it can be affected by soil coverage. The results obtained also contribute to database generation, important to model and estimate soil erosion. Total soil loss by erosion caused by natural rain, at Lavras, Minas Gerais, Brazil, were: 4.20, 1.86, 1.38 and 1.14 Mg ha(-1), respectively, for bare soil, maize, jack bean and the intercropping of both species, during evaluated period. Values of C factor of USLE were: 0.039, 0.054 and 0.077 Mg ha Mg-1 ha(-1) for maize, jack bean and intercropping between both crops, respectively. Maize presented lower vegetation cover index, followed by jack beans and consortium of the studied species. Intercropping between species showed greater potential on soil erosion control, since its cultivation resulted in lower soil losses than single crops cultivation, and this aspect is really important for small and medium farmers in the studied region

EFICIÊNCIA DE SISTEMAS DE IRRIGAÇÃO EM MUDAS DE ESPÉCIES FLORESTAIS NATIVAS PRODUZIDAS EM TUBETES

Seedlings low qualitycan result due toproblemsin irrigationand/or nutritionof seedlingsin their nursery phase. Regardingirrigation,problemscan ariserelatedto low uniformityof water application orits management, leading to lackorexcess of water.Whilethe excesscan leachnutrients, the deficit canaffectplant growth. Thus, this work had as objective to evaluate irrigation efficiency of a microsprinkler irrigation system at a forest native species nursery and also at sub-irrigation of forest native species being raised in recipient tubes The microsplinkler irrigation efficiency evaluation was performed in a native forest nursery at Itutinga - MG city, held in completely randomized design in split plots scheme, with the irrigation equipment on the plot (three levels: MA-20, Rondo and Inverted Rotor Spray) and three forest species on subplot.For efficiency evaluation in large tubes, the categories of subplot were: Araucaria angustifolia (Bert.) O. Ktze., Syagrus romanzoffiana (Cham.) Glassman and Joannesia princeps Vell.In small tubes, the three levels of subplots were the species: Guazuma ulmifolia Lam., Anadenanthera macrocarpa Benth. and Aspidosperma polyneuron Muell. The sub-irrigation efficiency evaluation was conducted in a greenhouse located at UFLA, in two sub-irrigation tanks with three replications, through calculation of uniformity coefficients for each sub-irrigated species, done in three replications. The largest application efficiency was obtained for the MA-20 emitter. There were no significant differences between the application efficiency of the emitters relative to the cultivated species, in both tube sizes. The efficiency in 300 cm³ tubes irrigation tank was 90.42%, while for 110 cm³ tubes it was 92.17%. Sub-irrigation tanks proved to be an interesting alternative for irrigation of the tested forest species seedlings, with high efficiency for both tubes sizes.A baixa qualidade de mudas pode advir de problemas na irrigação e/ou nutrição das mudas em sua fase de formação em viveiros.  Em relação à irrigação, problemas podem surgir referentes à má distribuição da água ou mesmo seu manejo, levando ao deficit ou ao excesso de irrigação, enquanto o excesso pode lixiviar nutrientes, o deficit pode prejudicar o desenvolvimento da planta. Assim, o presente trabalho teve como objetivos avaliar a eficiência de irrigação de um sistema de irrigação por microaspersão já instalado em um viveiro de mudas de espécies florestais e também avaliar a eficiência de um sistema de subirrigação de mudas florestais nativas cultivadas em tubetes. A avaliação da eficiência da microaspersão foi realizada em um viveiro de mudas de espécies nativas florestais na cidade de Itutinga - MG, o delineamento utilizado foi o inteiramente casualizado (DIC) em esquema de parcelas subdivididas, estando o equipamento de irrigação na parcela (três níveis: MA-20, Rondo e Inverted Rotor Spray) e três espécies florestais na subparcela. Na avaliação de eficiência em tubetes de 300 cm³, as categorias da subparcela foram: araucária (Araucaria angustifolia (Bert.) O. Ktze.), jerivá (Syagrus romanzoffiana (Cham.) Glassman) e cutieira (Joannesia princeps Vell.). Em tubetes de 110 cm³ os três níveis da subparcela foram as espécies: mutamba (Guazuma ulmifolia Lam.), angico-vermelho (Anadenanthera macrocarpa Benth.) e peroba-rosa (Aspidosperma polyneuron Muell.). A avaliação da eficiência da subirrigação foi realizada em uma estufa localizada na Universidade Federal de Lavras, em dois tanques de subirrigação em três repetições. As maiores eficiências de aplicação foram obtidas para o emissor modelo MA-20. Não houve diferenças significativas entre a eficiência de aplicação dos microaspersores em relação às espécies estudadas, em ambos os tubetes. A eficiência de irrigação no tanque de tubetes de 300 cm³ foi 90,42%, enquanto para tubetes de 110 cm³ foi 92,17%. Os tanques de subirrigação mostraram-se como alternativa interessante para irrigação de mudas das espécies florestais testadas, apresentando alta eficiência para os dois tamanhos de tubetes avaliados

DINÂMICA DAS CARACTERÍSTICAS QUÍMICAS DE UM SUBSTRATO FLORESTAL EXPOSTO À IRRIGAÇÃO

http://dx.doi.org/10.5902/1980509818456 The quality of seedlings produced at forest nurseries is related to several factors, including irrigation and the used substrate. Both have as their purposes the production of quality seedlings in a short time period, but over-irrigation can negatively affect the substrate nutrient content. This work aimed to evaluate the chemical characteristics dynamics of a forest substrate subjected to successive irrigation at sub-irrigation tanks in two plastic tubes sizes. To this end, plastic tubes of 110 and 300 cm³ were placed, containing forest substrate without the presence of new seedlings at two sub-irrigation tanks with recirculation, one for each tube size, built at Universidade Federal de Lavras. It was set up completely randomized design with two replications, being the treatment levels 0,6, 12, 18, 24 and 30 irrigations, five per day. The substrate chemical characteristics were evaluated: pH, phosphorus, potassium, iron, zinc, manganese, copper, calcium, magnesium, aluminum, boron, sulfur, effective CEC, organic matter and electrical conductivity. Additionally, before the irrigations counted as treatment, water samples were taken to check for possible changes in the quality of irrigation recycled water after successive irrigations. The sub-irrigations provided only changes in the potassium concentration in the substrate in both tubes, and most of the chemical characteristics assessed on the substrate were unchanged as a sub-irrigation function.http://dx.doi.org/10.5902/1980509818456A Qualidade das Mudas Florestais produzidas em viveiros ESTÁ relacionada a Fatores Diversos, Entre enguias um Irrigação EO Utilizado pelo substrato. Ambos possuem uma finalidade Como Produção de mudas de Qualidade em hum Curto Período de tempo, mas um Irrigação em Excesso PODE Influenciar negativamente não Conteúdo de Nutrientes fazer pelo substrato. ASSIM, este Trabalho Teve Como Objetivo avaliar a Dinâmica das Características Químicas de hum pelo substrato florestal submetido a sucessivas irrigações em tanques de subirrigação em Dois Tamanhos de tubetes. Para tal, were colocados tubetes de 110 e 300 cm³ contendo pelo substrato florestal novo, sem a presence de mudas, em Dois tanques de subirrigação com recirculação, um parágrafo Cada TAMANHO de tubete, construidos de na Universidade Federal de Lavras. FOI UM Montado Delineamento Inteiramente casualizado COM DUAS repetições, Sendo OS níveis fazer treatment 0, 6, 12, 18, 24 e 30 irrigações, dia cinco POR. Como Características Químicas avaliadas fazer pelo substrato were: em pH Água, fósforo, Potássio, ferro, zinco, manganês, cobre, calcio, Magnésio, Alumínio, boro, Enxofre, CTC Efetiva, Matéria Orgânica e condutividade Elétrica. Adicionalmente, were coletadas, as antes das irrigações contabilizadas Como treatment, Amostras de agua para Verificação de Possíveis alterações na Qualidade da Água de Irrigação reciclada APOS como irrigações sucessivas. Como subirrigações proporcionaram alterações na Concentração de Potássio APENAS não pelo substrato em tubetes, AMBOS OS SENDO that a maioria das Características Químicas avaliadas nsa Substratos permaneceu inalterada em Função das subirrigações

IRRIGATION EFFICIENCY ON NATIVE FOREST SEEDLINGS GROWN IN RECIPIENT TUBES

A baixa qualidade de mudas pode advir de problemas na irriga\ue7\ue3o e/ou nutri\ue7\ue3o das mudas em sua fase de forma\ue7\ue3o em viveiros. Em rela\ue7\ue3o \ue0 irriga\ue7\ue3o, problemas podem surgir referentes \ue0 m\ue1 distribui\ue7\ue3o da \ue1gua ou mesmo seu manejo, levando ao deficit ou ao excesso de irriga\ue7\ue3o, enquanto o excesso pode lixiviar nutrientes, o deficit pode prejudicar o desenvolvimento da planta. Assim, o presente trabalho teve como objetivos avaliar a efici\ueancia de irriga\ue7\ue3o de um sistema de irriga\ue7\ue3o por microaspers\ue3o j\ue1 instalado em um viveiro de mudas de esp\ue9cies florestais e tamb\ue9m avaliar a efici\ueancia de um sistema de subirriga\ue7\ue3o de mudas florestais nativas cultivadas em tubetes. A avalia\ue7\ue3o da efici\ueancia da microaspers\ue3o foi realizada em um viveiro de mudas de esp\ue9cies nativas florestais na cidade de Itutinga - MG, o delineamento utilizado foi o inteiramente casualizado (DIC) em esquema de parcelas subdivididas, estando o equipamento de irriga\ue7\ue3o na parcela (tr\ueas n\uedveis: MA-20, Rondo e Inverted Rotor Spray) e tr\ueas esp\ue9cies florestais na subparcela. Na avalia\ue7\ue3o de efici\ueancia em tubetes de 300 cm\ub3, as categorias da subparcela foram: arauc\ue1ria ( Araucaria angustifolia (Bert.) O. Ktze.), jeriv\ue1 ( Syagrus romanzoffiana (Cham.) Glassman) e cutieira ( Joannesia princeps Vell.). Em tubetes de 110 cm\ub3 os tr\ueas n\uedveis da subparcela foram as esp\ue9cies: mutamba ( Guazuma ulmifolia Lam.), angico-vermelho ( Anadenanthera macrocarpa Benth.) e peroba-rosa ( Aspidosperma polyneuron Muell.). A avalia\ue7\ue3o da efici\ueancia da subirriga\ue7\ue3o foi realizada em uma estufa localizada na Universidade Federal de Lavras, em dois tanques de subirriga\ue7\ue3o em tr\ueas repeti\ue7\uf5es. As maiores efici\ueancias de aplica\ue7\ue3o foram obtidas para o emissor modelo MA-20. N\ue3o houve diferen\ue7as significativas entre a efici\ueancia de aplica\ue7\ue3o dos microaspersores em rela\ue7\ue3o \ue0s esp\ue9cies estudadas, em ambos os tubetes. A efici\ueancia de irriga\ue7\ue3o no tanque de tubetes de 300 cm\ub3 foi 90,42%, enquanto para tubetes de 110 cm\ub3 foi 92,17%. Os tanques de subirriga\ue7\ue3o mostraram-se como alternativa interessante para irriga\ue7\ue3o de mudas das esp\ue9cies florestais testadas, apresentando alta efici\ueancia para os dois tamanhos de tubetes avaliados.Seedlings low quality can result due to problems in irrigation and/or nutrition of seedlings in their nursery phase. Regarding irrigation, problems can arise related to low uniformity of water application or its management, leading to lack or excess of water. While the excess can leach nutrients, the deficit can affect plant growth. Thus, this work had as objective to evaluate irrigation efficiency of a microsprinkler irrigation system at a forest native species nursery and also at sub-irrigation of forest native species being raised in recipient tubes The microsplinkler irrigation efficiency evaluation was performed in a native forest nursery at Itutinga - MG city, held in completely randomized design in split plots scheme, with the irrigation equipment on the plot (three levels: MA-20, Rondo and Inverted Rotor Spray) and three forest species on subplot. For efficiency evaluation in large tubes, the categories of subplot were: Araucaria angustifolia (Bert.) O. Ktze., Syagrus romanzoffiana (Cham.) Glassman and Joannesia princeps Vell. In small tubes, the three levels of subplots were the species: Guazuma ulmifolia Lam., Anadenanthera macrocarpa Benth. and Aspidosperma polyneuron Muell. The sub-irrigation efficiency evaluation was conducted in a greenhouse located at UFLA, in two sub-irrigation tanks with three replications, through calculation of uniformity coefficients for each sub-irrigated species, done in three replications. The largest application efficiency was obtained for the MA- 20 emitter. There were no significant differences between the application efficiency of the emitters relative to the cultivated species, in both tube sizes. The efficiency in 300 cm\ub3 tubes irrigation tank was 90.42%, while for 110 cm\ub3 tubes it was 92.17%. Sub-irrigation tanks proved to be an interesting alternative for irrigation of the tested forest species seedlings, with high efficiency for both tubes sizes

DYNAMICS OF THE CHEMICAL CHARACTERISTICS OF A FOREST SUBSTRATE EXPOSED TO IRRIGATION

A qualidade das mudas florestais produzidas em viveiros est\ue1 relacionada a diversos fatores, entre eles a irriga\ue7\ue3o e o substrato utilizado. Ambos possuem como finalidade a produ\ue7\ue3o de mudas de qualidade em um curto per\uedodo de tempo, mas a irriga\ue7\ue3o em excesso pode influenciar negativamente no conte\ufado de nutrientes do substrato. Assim, este trabalho teve como objetivo avaliar a din\ue2mica das caracter\uedsticas qu\uedmicas de um substrato florestal submetido a sucessivas irriga\ue7\uf5es em tanques de subirriga\ue7\ue3o em dois tamanhos de tubetes. Para tal, foram colocados tubetes de 110 e 300 cm\ub3 contendo substrato florestal novo, sem a presen\ue7a de mudas, em dois tanques de subirriga\ue7\ue3o com recircula\ue7\ue3o, um para cada tamanho de tubete, constru\ueddos na Universidade Federal de Lavras. Foi montado um Delineamento Inteiramente Casualizado com duas repeti\ue7\uf5es, sendo os n\uedveis do tratamento 0, 6, 12, 18, 24 e 30 irriga\ue7\uf5es, cinco por dia. As caracter\uedsticas qu\uedmicas avaliadas do substrato foram: pH em \ue1gua, f\uf3sforo, pot\ue1ssio, ferro, zinco, mangan\ueas, cobre, c\ue1lcio, magn\ue9sio, alum\uednio, boro, enxofre, CTC efetiva, mat\ue9ria org\ue2nica e condutividade el\ue9trica. Adicionalmente, foram coletadas, antes das irriga\ue7\uf5es contabilizadas como tratamento, amostras de \ue1gua para verifica\ue7\ue3o de poss\uedveis altera\ue7\uf5es na qualidade da \ue1gua de irriga\ue7\ue3o reciclada ap\uf3s as sucessivas irriga\ue7\uf5es. As subirriga\ue7\uf5es proporcionaram altera\ue7\uf5es na concentra\ue7\ue3o apenas de pot\ue1ssio no substrato em ambos os tubetes, sendo que a maioria das caracter\uedsticas qu\uedmicas avaliadas nos substratos permaneceu inalterada em fun\ue7\ue3o das subirriga\ue7\uf5es.The quality of seedlings produced at forest nurseries is related to several factors, including irrigation and the used substrate. Both have as their purposes the production of quality seedlings in a short time period, but over-irrigation can negatively affect the substrate nutrient content. This work aimed to evaluate the chemical characteristics dynamics of a forest substrate subjected to successive irrigation at sub-irrigation tanks in two plastic tubes sizes. To this end, plastic tubes of 110 and 300 cm\ub3 were placed, containing forest substrate without the presence of new seedlings at two sub-irrigation tanks with recirculation, one for each tube size, built at Universidade Federal de Lavras. It was set up completely randomized design with two replications, being the treatment levels 0,6, 12, 18, 24 and 30 irrigations, five per day. The substrate chemical characteristics were evaluated: pH, phosphorus, potassium, iron, zinc, manganese, copper, calcium, magnesium, aluminum, boron, sulfur, effective CEC, organic matter and electrical conductivity. Additionally, before the irrigations counted as treatment, water samples were taken to check for possible changes in the quality of irrigation recycled water after successive irrigations. The sub-irrigations provided only changes in the potassium concentration in the substrate in both tubes, and most of the chemical characteristics assessed on the substrate were unchanged as a sub-irrigation function

Cargas superficiais da fração argila de solos influenciadas pela vinhaça e fósforo

Effects of vinasse, P sorption and the interaction vinasse-phosphorus on zeta potential and point of zero charge (PZC) as well as the effects of vinasse on P sorption on clay-fraction samples from two soils were evaluated. The vinasse and P sorption influenced the surface charge of clay fraction of both soils. Sorption of P increased negative charges from soil particles reducing PZC. These effects were more pronounced when clay fraction was previously treated with vinasse. Vinasse treatment reduced P sorption, probably due to coating of P-adsorption sites and by enhancing the negative charges

Traçando a origem de sedimentos de reservatórios usando propriedades magnéticas no Sudeste do Brasil

Determining the origin of eroded soil is essential to design effective soil erosion control strategies which preserve the soil resource, enhance agricultural productivity, and reduce the negative impacts of soil erosion, in-field and off-field. Magnetic properties have been widely used in temperate environments to identify sediment sources, pathways and links, but there have been very few applications in tropical and subtropical environments. Therefore, in this paper we investigated reservoir sediment sources in the Upper Grande River Basin, Southeastern Brazil, using sediment tracing techniques based on magnetic parameters (low and high frequency magnetic susceptibility, frequency dependent susceptibility). The different parent materials and subtropical weathering conditions resulted in soils having different Fe oxide minerals and Fe oxide contents, promoting magnetic variability that allowed comparison and identification of possible sources of reservoir sediments in order to reduce water erosion impacts. The results indicate the suitability of magnetic properties as a tracer for soil erosion studies in tropical environments

Physical, ecological and human dimensions of environmental change in Brazil's Pantanal wetland : synthesis and research agenda

This article was conceived at a Newton Fund Researcher Links Workshop “Climate and Landscape Change in the Pantanal: assessing environmental vulnerabilities and future water security in Brazil's wetland wilderness”. The authors would like to thank Philip Stickler for kindly producing Fig. 1 for this article. Funding from Northumbria University for open access to this article is gratefully acknowledged.The Pantanal is the world's largest freshwater wetland, located in the geographical centre of South America. It is relatively well conserved, and features unique landscapes, ecosystems, and traditional cultural practices, shaped by the dynamic interaction of climatological, hydrological, geological, ecological, and anthropogenic factors. Its ecological integrity is increasingly threatened by human activities, particularly, in the wider catchment area, for example, deforestation, agricultural intensification, and construction of hydropower plants, with implications for local people's livelihoods. We present a synthesis of current literature on physical, ecological, and human dimensions of environmental change in the wetland, outline key research gaps, and discuss environmental management implications. The literature review suggests that better integration of insights from multiple disciplines is needed and that environmental management could be improved through a better grounding in traditional practices and local perspectives. We conclude with four recommendations: First, future environmental change research should build more strongly on the positive example of a small number of case studies where traditional and local knowledge of the environment was put into a dialogue with scientific knowledge and techniques. Second, we recommend a more explicit consideration of longer temporal scales (>10 years) in environmental change research, making use of oral and written histories, as well as palaeoecological techniques, to understand system responses to different magnitudes of human and climatic pressures, and ultimately, to inform future adaptation activities. Third, we suggest that enhanced stakeholder participation in conceiving and implementing research projects in the Pantanal would strengthen the practical relevance of research in addressing environmental management challenges, livelihood needs, and advocacy processes. Fourth, we call for a more systemic and integrative perspective on environmental education, which encompasses engagement activities between researchers, policy-makers, and citizens, to foster environmental awareness, scientific literacy, and public participation.Publisher PDFPeer reviewe