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Agroforestry systems are multifunctional land-use systems that promote soil life. Despite their large potential spatio-temporal complexity, the majority of studies that investigated soil organisms in temperate cropland agroforestry systems focused on rather non-complex systems. Here, we investigated the topsoil and subsoil microbiome of two complex and innovative alley cropping systems: an agrosilvopastoral system combining poplar trees, crops, and livestock and a syntropic agroforestry system combining 35 tree and shrub species with forage crops. Increasing soil depth resulted in a decline of bacterial and fungal richness and a community shift towards oligotrophic taxa in both agroforestry systems, which we attribute to resource-deprived conditions in subsoil. At each soil depth, the microbiome of the tree rows was compositionally distinct from the crop rows. We detected a shift towards beneficial microorganisms as well as a decline in putative phytopathogens under the trees as compared to the crop rows. Finally, based on our results on community dissimilarity, we found that compared to an open cropland without trees, spatial heterogeneity introduced by the tree rows in the agrosilvopastoral system translated into a compositionally less homogeneous soil microbiome, highlighting the potential of agroforestry to counteract the homogenization of the soil microbiome through agriculture. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the damage caused to trees by beef cattle in integrated crop-livestock-forestry (ICLF) systems with different tree arrangements. The treatments evaluated were the ICLF-1L system, with single lines of eucalyptus (187 trees ha−1), and the ICLF-3L system, with three lines of eucalyptus (446 trees ha−1). The experimental design consisted of randomized blocks with four replications. The eucalyptus clone I-224 and Nellore cattle breed were used for this study. The damage caused by cattle to eucalyptus was classified as follows: Tb, trunk breakage; Ti, trunk injury reaching the wood by removing the cambium tissue; Bb, breakage branches greater than 2 cm in diameter; Bi, bark injury without reaching the cambium; Bt, breakage of thin branches and browsing on leaves; and Di, lesions greater than 5 cm in diameter. The damage score was calculated for each tree by the sum of grade the damage that cattle caused to the tree: Tb = 10.0; Ti = 4.0; Bb = 2.0; Bi = 1.5; Bt = 1.0; and Di = 1.0. The diameter at breast height (DBH), height and wood volume of the trees were also evaluated. The frequencies of Ti, Bb and Di were greater in the ICLF-1L system than in the ICLF-3L system (P < 0.05); in contrast, the frequencies of Bt and Bi were greater in the ICLF-3L system. The damage score was greater in the ICLF-1L system (6.61; P < 0.05) than in the ICLF-3L system (4.60). The height was greater in the ICLF-3L system (P < 0.05), and the DBH and individual wood volume did not differ between the systems (P > 0.05). Cattle cause damage to eucalyptus trees regardless of tree arrangement (ICLF-1L and ICLF-3L), but the damages were greater in the ICLF-1L system. Although the damages were more severe in ICLF-1L, tree growth and wood production were the same in both systems. Additional studies should be conducted to assess the impacts of livestock damage in wood quality. [ABSTRACT FROM AUTHOR]

Integrated agricultural production systems can increase soil organic carbon stocks over time and contribute to the mitigation of climate change. The present study aimed to evaluate soil carbon stocks, accumulation rates (TOC), total nitrogen (TN), and the quality of soil organic matter (SOM) after the transition of a low-productivity pasture into agrosilvopastoral systems in the Cerrado biome. We evaluated an 11-year-old experiment, and the treatments studied were: Eucalyptus + buffel grass; Eucalyptus + cowpea; Eucalyptus + pigeon pea; eucalyptus + buffel grass + cowpea; Eucalyptus + buffel grass + pigeon pea; Eucalyptus in monoculture (with a 20 × 3 m tree arrangement and no cultivation between rows but with a history of forage and grain crop production); and a low-productivity pasture as additional treatment and reference to the soil condition previously the land-use change. In this study, TOC and TN stocks and accumulation, labile (LC) and non-labile carbon (NLC), and SOM humic fractions were evaluated at 0-10, 10-20, 20-40, and 0-40 cm depth layers. Integrated farming systems have increased TOC and TN, NLC, carbon contents and stocks in SOM chemical fractions in all depths and TOC and TN accumulation of 5.22 Mg ha-1 year-1 and 0.23 Mg ha-1 year-1, respectively, at the 0-40 cm depth layer. The integration of Eucalyptus with legumes or buffel grass increased the LC content in the surface layer of the soil. The transition from low-productivity pasture into integrated farming systems can promote the recovery of SOM and soil quality. Hence, our results suggest that agrosilvopastoral systems can be used as sustainable farming systems in the Cerrado biome. [ABSTRACT FROM AUTHOR]

The paper presents a descriptive model, applicable in agricultural theory and practice, for determining the quantity of alfalfa hay obtained from a land surface, using remote investigations, by geospatial methods and means. The working algorithm was tested in a rural area located in the northern part of Romania, in the Humor Depression, and the data acquisition was made with DJI Phantom 4 Pro - Unmanned Aerial Vehicle equipment. For the automated calculation of the amount of alfalfa hay harvested from a certain surface and stored as haystacks, the following steps were carried out: processing the images acquired with the drone to obtain the point clouds, determining the 3D model of the haystacks, calculating the volume of hay stored in the stacks and converting the volume in quantity of hay/surface. As a result of the measurements and calculations carried out, a quantity of hay of 11.96 tons/ha was obtained, data verified and validated by the researches from the specialized literature. Compared with the agronomic methods, the use of the geomatics techniques, to determine the quantity of hay harvested from an agricultural area, presents a series of practical and economic advantages: they exclude the manual measurements in the field and, therefore, the displacements on extended surfaces; reduce the working time; have high precision because, for the estimation of the haystacks volume, three-dimensional models are used, instead of the traditional mathematical formulas. At the same time, geospatial data is acquired through drone flying, which can be used in other types of analysis. The working algorithm can also be applied to other studied objectives or research topics.

Integrated crop–livestock–forestry systems are a sustainable agriculture system based on the intensification of land use to produce food, fiber and energy and are a priority theme in the public policy of the Brazilian government. The lack of technical and scientific knowledge may be one of the most challenging factors contributing to the low adoption of these complex, integrated systems. The objective of this study was to evaluate the crop, livestock and forestry performance assessment under different production systems in the north of Mato Grosso. Ten production systems were evaluated from 2011 to 2015, including crop production (soybean/corn), livestock (palisade grass pastures with Nellore steers) and forestry (Eucalyptus urograndis H13), in both single and integrated systems. Annual evaluations of production components in the crops, forage, cattle and trees were carried out. A negative influence on the grain yields in the fourth and fifth years for soybean and the third year onward for maize was observed as a result of the presence of the tree in the production systems. Forage availability and animal weight gain were increased by the rotation of crop–livestock, while no differences were found for wood individual volume yield among the production systems. [ABSTRACT FROM AUTHOR]

To determine if reduced tree densities (number of trees per unit area) lead to changes in micro-meteorological and tree physiological characteristics, two areas with different tree densities were assessed. One was an agrosilvopastoral system (AGP) with low tree density, and the other, a secondary forest (SF) with greater tree numbers, both located in a semiarid region of Brazil. Data were collected simultaneously by two automated weather stations: rainfall, air (Ta) and soil temperatures (Ts5cm), relative humidity (RHair), photosynthetically active radiation (PAR), soil moisture at two depths (Ms30cm and Ms50cm), and wind velocity (Vw). Net photosynthesis in Cordia oncocalyx Allemão trees was measured with an infrared gas analyzer in February, March, May, July, August and September 2011, which encompasses a rainy period followed by a dry period. Average values of Ta, Ts5cm, Vw and PAR were greater and average values of RHair and Ms50cm were lesser in the AGP. Photosynthetic rates were greater in plants growing under the AGP at the onset of the dry season when Vw, PAR and Ts5cm were greater and Ms50cm was lesser. Photosynthetic rates correlated strongly with physical parameters during the dry season, especially under SF. Differences in tree numbers between AGP and SF led to differences in physical environmental parameters; however, the latter had less influence on photosynthetic rates in C. oncocalyx during the rainy season. During the dry season, all physical parameters had an impact on net photosynthesis under SF but not under AGP. This indicates a certain independence of plants in AGP. [ABSTRACT FROM AUTHOR]

ABSTRACT The use of trees in integrated crop-livestock-forestry systems (ICLF) allows diversifying production, increasing profitability per area, and providing a higher animal comfort. However, the influence of tree component on soil chemical attributes in this system is still little studied. This study aimed to assess the effect of trees and sun-exposed faces to solar radiation on soil nutrient availability at different distances of tree rows in an integrated crop-livestock-forestry system. This study was carried out in the northern Mato Grosso State, Brazil, in the Cerrado - Amazon Forest transition region in an ICLF with the tree component formed by three eucalyptus rows. The assessment carried out in the second year of ICLF implantation considered the effect of tree distances (3, 6, 10, and 15 m) on two sun-exposed faces to solar radiation (north and south) on the main soil chemical attributes. Soil sampling was performed at depths of 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. The results indicated a homogeneity of the average nutrient contents obtained in the north and south-exposed faces, as well as in the comparison of the same distances in both assessed sun-exposed faces. Effects of trees on soil chemical attributes were verified only when an isolated analysis was carried out in the north-exposed face for K and Al contents. For these attributes, the increased distance in the row was associated with a reduction in their contents in the more superficial and deeper layers, respectively. Trees do not significantly affect soil nutrient availability in the first years of ICLF implantation in systems with homogeneity of solar radiation incidence in the sun-exposed faces although there may be discrete nutrient reductions with the distance of trees.

ABSTRACT Integrated crop-livestock-forest (iCLF) systems have gained prominence in the past decades as an alternative of sustainable land use, particularly in regions in which there is pressure against agricultural expansion in protected ecosystems such as the Brazilian Amazon. In this context, the objective of this study is to evaluate the effects of one year of use of the iCLF system in the Cerrado/Amazon transition region to determine its impact on soil quality compared to other traditional land uses in the region (planted forest, crop, forage, and native forest). The results indicated that the iCLF system did not jeopardize the soil physical quality, and only the crop land use affected the soil physical attributes. The land uses with the lowest impact on the physical condition of the soil were the iCLF system and the planted forest.

ABSTRACT The contribution of nutrient cycling from eucalyptus residues in an Integrated Crop-Livestock System (ICLS) extracting potassium (K) in deeper layers and releasing on the surface should be further investigated in soils with variable charge. The objectives of this study were to evaluate the effects of K rates (0, 100, 200 and 300 kg ha-1 yr-1 of K2O) applied on the soil surface in the entire area in rows of ICLS with eucalyptus, and relate these doses to macronutrient levels in the soil. The implemented experimental design was a randomized complete block using a split plot with three replications. The plot consisted of two rows and subplot by K rates. Soil fertility attributes were conducted at 6, 12 and 30 months after the start of the experiment. Medium to high concentrations of K were observed in profile up to 12 months, and very low concentrations of K were observed in the profile 30 months after the experiment was initiated. High concentrations of Ca, Mg were observed throughout the profile favoring saturation in an effective cation exchange capacity (ECEC). However, high K saturation in ECEC was observed at 6 and 12 months, and this decreased at 30 months of study. No leaching was observed, although acidity was high.

Objetivou-se com este estudo avaliar o carbono orgânico total e as frações físicas e químicas da matéria orgânica (MO) do solo em um Argissolo Vermelho Eutrófico arênico, submetido a diferentes sistemas de uso. Os sistemas de uso do solo avaliados foram: florestamento homogêneo de Eucalyptus grandis (EUC), sistema agrossilvipastoril na faixa (ASP) e campo nativo (CN), nas camadas de 0,000-0,025m e de 0,025-0,075m. A fração grosseira (CFG) e o carbono associado aos minerais (CAM) foram obtidos por meio de fracionamento físico granulométrico. As frações leve livre (FLL), leve oclusa (FLO) e pesada (FP) foram obtidas por meio de fracionamento físico densimétrico. As frações não húmicas (NH), ácido fúlvico (AF), ácido húmico (AH) e humina (HU) foram obtidas por meio de fracionamento químico. O sistema EUC promoveu maiores estoques de carbono orgânico total, CFG, FLL e FLO e na fração AF nas camadas avaliadas. Na camada superficial, os mecanismos de proteção da MO por recalcitrância molecular e estabilização química estão sobrepondo a estabilidade decorrente da oclusão em agregados. Com a dificuldade de formar agregados, devido a matrizes arenosas desse solo, o carbono jovem que entra no sistema é decomposto pelos microrganismos, entrando em um estágio mais avançado de decomposição e, nesse caso, formando associações com as partículas silte e argila, mesmo em solos em que o percentual de argila é baixo. Através do fracionamento químico, observou-se que a maior parte da MO do solo encontra-se armazenada na forma de HU.The objective of this study was to evaluate the total organic carbon and the physical and chemical fractions of organic matter in an Alfisol under different use systems. The land use systems evaluated was homogeneous forestry of Eucalyptus grandis, agrosilvopastoral system and native grassland, in layers from 0.000-0.025 and 0.025-0.075m depth. The coarse fraction (CFG) and the carbon associated minerals (CAM) were obtained by physical fractionation. The free light fraction (FLL), light occluded (FLO) and heavy (FP) were obtained by densimetric physical fractionation. The non-humicfractions (NH), fulvic acid (AF), humic acid (HA) and humin (HU) were obtained by chemical fractionation. The Eucalyptus grandis system promoted higher total organic carbon, CFG, FLL and FLO and AF. In the surface layer, the protective recalcitrance mechanisms by organic matter molecular and chemical stabilization are overlapping stability which result from aggregates occlusion. As is difficult to form aggregates due to sandy soil matrix, carbon youth which enter the system is decomposed by microorganisms going to a more advanced stage of decomposition, forming in this case associations with silt and clay particles. This occurs in soils where the clay percentage is low. Through the fractionation it was observed that most of the soil organic matter is stored in the form of HU.

The objective of this study was to evaluate the total organic carbon and the physical and chemical fractions of organic matter in an Alfisol under different use systems. The land use systems evaluated was homogeneous forestry of Eucalyptus grandis. agrosilvopastoral system and native grassland, in layers from 0.000-0.025 and 0.025-0.075m depth. The coarse fraction (CFG) and the carbon associated minerals (CAM) were obtained by physical fractionation. The free light fraction (FLL), light occluded (FLO) and heavy (FP) were obtained by densimetric physical fractionation. The non-humicfractions (NH), fulvic acid (AF), humic acid (HA) and liumin (HU) were obtained by chemical fractionation. The Eucalyptus grandis system promoted higher total organic carbon, CFG, FLL and FLO and AF. In the surface layer, the protective recalcitrance mechanisms by organic matter molecular and chemical stabilization are overlapping stability which result from aggregates occlusion. As is difficult to form aggregates due to sandy soil matrix, carbon youth which enter the system is decomposed by microorganisms going to a more advanced stage of decomposition, forming in this case associations with silt and clay particles. This occurs in soils where the clay percentage is low. Through the fractionation it was observed that most of the soil organic matter is stored in the form of HU. [ABSTRACT FROM AUTHOR]

Integrated crop-livestock systems (ICLS) include diversified agricultural practices, like crops and animals grazing in the same area and frequently with afforestation. A return to these practices has been proposed in recent years, aiming to reach some benefits that may include a reduction in plant diseases, one of the main constraints in Brazilian crops. However, these benefits rely mainly on the resilience and the self-regulating capacity of the systems, and practical examples of the influence of ICLS on plant diseases are still scarce. The objective of the present work is to show how ICLS arrangements can reduce plant diseases. We carried out a four years investigation on soybean and corn diseases in agropastoral (AP) and agrosilvopastoral (ASP) systems, compared to a non-integrated control (CO), in a long-term field experiment established in 2006 in the region of Campos Gerais, Paraná state, Brazil. The tree component of the ASP system was eucalyptus and silver oak. Soybean and corn were cultivated alternately as summer crops, and the natural occurrence of diseases evaluated from 2012 to 2015 sowings. Results show that the agricultural diversification promoted by ICLS can reduce foliar diseases intensity, and the ASP system showed the best results. The rust severity was 28.2 and 34.2% in ASP and AP systems in 2012, and 8.5 and 12.4% in ASP and AP in 2014. White-spot severity was 1.6, 2.2, and 3.1% in ASP, AP, and CO systems in 2013, and 0.6, 1.3, and 1.3% in ASP, AP, and CO in 2015. Other diseases, like downy-mildew on soybean and gray-leaf-spot on corn, were also less severe in ASP compared to other systems. Micrometeorological variables recorded inside soybean and corn canopy contributed to understanding the influence of ICLS arrangements on plant diseases, allowing concluding that microclimate is the main drive influencing disease reduction in the aerial part of crops in ICLS. The ICLS, mainly the agrosilvopastoral system, pose as a less diseases susceptible and consequently an environmentally friendly system. Knowing the requirements of the pathogens of a crop species is fundamental in planning a production system, avoiding or minimizing risks. The influence of trees on plant diseases of afforested production systems is discussed. • Agricultural diversification reduces soybean and corn diseases. • Afforested production system is more effective than others in reducing diseases. • Microclimate is the main driver for reducing diseases in afforested systems. • Knowing the requirements of pathogens is fundamental in planning production system. [ABSTRACT FROM AUTHOR]

Land use was examined in three settlements - Pedro Peixoto in Acre and Theobroma in Rondonia, Brazil, and Pucallpa, in Peru. Research aimed at characterizing the differences in land use after initial slash-and-burn, and presenting hypotheses to assess the feasibility of improved land uses. Settlers in the Amazon practice slash-and-burn agriculture in forest lands to produce annual crops. After cropping, lands are converted to pasture, or planted with perennial crops, or fallowed in anticipation of future annual crop production. Land use after slash-and-burn cultivation in forest lands differed among the colonies examined. Whereas colonists in Pedro Peixoto converted lands to pasture for cattle production, settlers in Theobroma adopted a strategy encompassing both dual-purpose (milk and meat) cattle and perennial crop production. The more heterogeneous settlers in Pucallpa, who included small-scale cattle ranchers and riverine and forest slash-and-burnfarmers, gave more importance to perennial crops. Hypotheses are suggested regarding the described land use differences, and implicationsfor the adoption of agroforestry are discussed. [ABSTRACT FROM AUTHOR]