abundance ofthe arbuscular mycorrhizal fungi (AMF) to a greater degree than did the conventional farming systems. However, the same authors emphasized that such a response could vary, principally because of climate variations, management techniques and a variety of possible combinations in such associations (e.g., tree arrangements and tree species, tree density and age, etc.). The association oftrees with pastures in general appears to induce a positive change in thesoil quality through higher chances for nutrient cycling (Batista et al., 2018). However, microclimate alterations within the system and therefore water availability, together with the competition between treesand intercropping for light and nutrients may influence the quantity and quality ofthe organic residues deposited onthesoil, besides their spatial distribution and hence, the resultant microbiologicalattributes. Thus, data onthe manner in which the tree systemsand such types of more sustainable production practices affect the microbial community and populations like AMF continue to be required (Ferreira et al., 2012).
Brazil is the biggest coffee producer in the world and different plantation management systems have been applied to improve sustainability andsoil quality. Little is known about the environmental effectsof these different management systems, therefore, the goal of this study was to use soil biological parameters as indicators of changes. Soils from plantations in Southeastern Brazil with conventional (CC), organic (OC) andintegrated management systems containing intercropping of Brachiaria decumbens (IB) or Arachis pintoi (IA) were sampled. Total organic carbon (TOC), microbial biomass carbon (MBC) andnitrogen (MBN), microbial activity (C-CO 2 ), metabolic quotient (qCO 2 ), the enzymes dehydrogenase, urease, acid phosphatase and arylsulphatase, arbuscular mycorrhizal fungi (AMF) colonization and number of spores andsoil fauna were evaluated. The greatest difference between the management systems was seen in soil organic matter content. The largest quantity of TOC was found in the OC, andthe smallest was found in IA. TOC content influenced soil biological parameters. The use of all combined attributes was necessary to distinguish the four systems. Each management presented distinct faunal structure, andthe data obtained with the trap method was more reliable than the TSBF (Tropical Soils) method. A canonic correlation analysis showed that Isopoda was correlated with TOC andthe most abundant order with OC. Isoptera was the most abundant faunal order in IA and correlated with MBC. Overall, OC had higher values for most ofthe biological measurements and higher populations of Oligochaeta and Isopoda, corroborating with the concept that the OC is a more sustainable system.
Muniz et al. (2011) reported that the recovery of degraded pastures by implementing ICLS on Oxisols increased microbial biomass carbon (MBC), even when compared with native cerrado (Brazilian savanna vegetation). Similarly, Frazão et al. (2010) showed that MBC and microbial biomass nitrogen (MBN) values may be higher or equivalent to those of native cerrado, in a Typic Quartzipsamment both under cultivated pasture [Urochloa decumbens (Stapf) R.D.Webster] and ICLS. Moreover, the practice of annual crops and pasture grasses in the same area (ICLS) can promote root development andsoil organic carbon, providing favorable conditions for SMB (Loss et al., 2012). In this context, the ICLFS may further increase soil organic carbon and microbial biomass, improving soil quality. However, due to the interactions of animal husbandry with annual crops and forest species, this system is dynamic and complex, requiring more study.
ABSTRACT - A significant increase in the use ofintegrated farming systems have been observed in the Brazilian Cerrado, such as crop-livestock integration (CLI), which combined with the no-tillage system (NTS) have shown significant influence onsoil properties. Therefore, the objective of this work was to evaluate the influence of a CLI system onthe chemical, physical andmicrobiologicalsoil characteristics, in an area in the Cerrado biome, Montividiu, State of Goias, Brazil. Thesoil fertility, remaining phosphorus (Prem), total organic carbon (TOC), total nitrogen (Nt), aggregate stability (geometric mean diameter – GMD), microbial respiration (C-CO 2 ) and easily-extractable glomalin-related soil protein (EE-GRSP) were evaluated. Soil
from thesoil. Here, the Ni concentrations extracted with Mehlich-3 and DTPA increased linearly as a function ofthe Ni applied to soil (Table 3). The Mehlich-3 approach recovered more Ni than DTPA (Table 3) because DTPA (calcium chloride and triethanolamine) removes Ni only by forming complexes, whereas Mehlich-3 (acetic acid, ammonium nitrate, nitric acid, ammonium fluoride and EDTA) additionally removes Ni by exchange reactions. The efficiency of Ni-extraction methods for the analysis ofsoil Ni availability to plants on a routine basis is still a matter of study. The efficiency of Mehlich-3 for the determination ofsoil Ni availability for tobacco (Mulchi et al., 1991), common bean (Abreu et al., 1995), sorghum (Revoredo & Mello, 2006), and lettuce and common bean (Fontes et al., 2008) has been reported. For DTPA soil extraction, the Ni recovered from soil correlated with Ni in corn leaves (Oliveira, 1995) and with Ni in the leaves and grains of common bean (Berton et al., 2006). Here, the Ni concentrations recovered by DTPA and M-3 were correlated with the Ni concentrations and contents in lettuce shoots (Table 5), indicating the efficiency of these extractors for Ni analysis in the Red-Yellow Latosol studied.
A similar trend was observed for the metabolic quotient, with higher values in soil under conventional tillage at depths of 0.00-0.05 m and 0.05-0.10 m for the 2006/07 season, and at all depths for 2007/08. These results are in agreement with Silva et al. (2007) and Cunha et al. (2011). High values for the metabolic quotient demonstrate the imbalance of agricultural areas (MOURA; LACERDA; RAMOS, 2013), as in the case of plots subjected to conventional tillage. This type of management promotes disruption ofthesoil aggregates, increasing the mineralisation ofthe organic matter content and increasing the release of carbon dioxide into the atmosphere (CARNEIRO et al., 2009). Similar results were found by Franchini et al. (2007), who, in long-term trials in Paraná, observed the lower metabolic rate in soil under direct seeding contribute to a greater accumulation of carbon in thesoil.
Abstract – The objective of this work was to evaluate theeffectsof lignin, hemicellulose, and cellulose concentrations in the decomposition process of cover plant residues with potential use in no-tillage with corn, for crop-livestockintegrated system, in the Cerrado region. The experiment was carried out at Embrapa Cerrados, in Planaltina, DF, Brazil in a split plot experimental design. The plots were represented by the plant species andthe subplots by harvesting times, with three replicates. The cover plants Urochloa ruziziensis, Canavalia brasiliensis, Cajanus cajan, Pennisetum glaucum, Mucuna aterrima, Raphanus sativus, Sorghum bicolor were evaluated together with spontaneous plants in the fallow. Cover plants with lower lignin concentrations and, consequently, higher residue decomposition such as C. brasiliensis and U. ruziziensis promoted higher corn yield. High concentrations of lignin inhibit plant residue decomposition and this is favorable for thesoil cover. Lower concentrations of lignin result in accelerated plant decomposition, more efficient nutrient cycling, and higher corn yield.
4. In order to determine the water infiltration rate in thesoil, in each soil management system, 3 samples were taken, before and after the iLPF installation. The ring infiltrator method was used, consisting of two concentric rings, with a diameter of 30 cm and 50 cm, and a height of 35 cm (both are fixed to the ground up to approximately 5 cm deep). The reading interval was two minutes during two hours of evaluation.
Thesoil management systems consisted of: ICLS with 0.25 m grazing height; ICLS with 0.35 m grazing height, predefined as the adequate grazing height for soil physical properties (Bonetti et al., 2015); ICLS with 0.45 m grazing height; and nongrazed area (NG), with brachiaria as cover crop. Each experimental plot had a 2.0 ha area, in a randomized block design in a split- plot arrangement, considering the treatments as the main plot, andthe seasons as the split plots, with three replicates. The winter grazing height was controlled by the entry and exit of animals, and it was monitored every 14 days with a sward stick (Jenquip, model SS400M, Auckland, New Zealand), based onthe methodology of Barthram (1985), with the determination of 50 points per plot. Grazing was performed by female cattle with an average of 450 kg live weight, beginning in July of each year, when forage reached 4,000 kg ha -1 mean
Braz. J. of Develop., Curitiba, v. 6, n. 7, p.47638-47651 jul. 2020 . ISSN 2525-8761 The adoption ofintegrated agricultural production systems has ability to improve physical, chemical, and biological soil conditions, increase cycling and efficiency of use of nutrients, reduce production costs, increase income for producer and enable recovery of areas with degraded pastures (Bortolini et al. 2013, Diel et al. 2014, Kunrath et al. 2015). There are countless benefits provided by integratedcrop-livestock system (SILP) as an alternative to replace unsustainable systemsand its adoption in agricultural areas in Brazil has been increasing (Quintino et al. 2016).
Sustainable agricultural production systems can improve physical attributesofsoil as well as increase carbon andnitrogen stocks in soils. The objective of this study was to evaluate changes in the stability ofsoil aggregates and contents and stocks of carbon andnitrogen after the conversion of native forest to crop-livestock-forest integration systems in the region of Western Pará. Soil samples from five management systems (including a control) were collected at three depths in a randomized block design, with five replications. The stability ofthe aggregates, soil density, particle density, and total soil porosity, as well as total carbon andnitrogenand their respective stocks were evaluated. The native forest had the highest percentages of macroaggregates, followed by the integration system with African mahogany. At a depth of 0-0.10 m, the contents and stocks of carbon were higher in the agricultural area and in the integration system with cumaru, whereas nitrogen contents and stocks were higher in the native forest, followed by the integration systems with mahogany and cumaru. Compared to the other systems, the pasture area stored more carbon at depths of 0-0.10 and 0.10-0.20 m.
In areas where livestock needs to be integrated with crops, that is, where traditional grain cropping is adopted without livestock exploration (Anghinoni et al., 2013), the impacts of winter grazing on summer crop performance are not clearly established, especially for soybean. According to Martins et al. (2014a), the yield differences between areas with and without grazing occur mainly in summer seasons affected by drought, with rainfall above the climatological normal, when grazed areas result in lower yields. A plausible explanation for this behavior might be found in soiland plant water-related properties and in soybean physiology, since a poor crop establishment and a higher weed pressure were observed in areas where intensive grazing was performed before soybean sowing (Kunrath et al., 2015). However, due to the difficulty in measuring plant water status in thesoil-plant-atmosphere continuum (Whitmore & Whalley, 2009), this kind of approach is still scarce, particularly regarding ICL systems.
PC1 shows that the highest GYs were observed in the most compacted areas while the incidence of grain stain was higher in less compacted areas. The presence of macropores is important for soil aeration, but it also contributes to the reduced volume of micropores and, thus, of retained water. The lower micropore volume accentuated the problem caused by water stress, which may explain the negative correlation between GY and MA, and positive with MI. Areas with higher MI held higher water volume in thesoil, allowing higher productivity due to the occurrence ofthe Indian summer during the rice flowering stage (Figure 2).
According to Oliveira, Macedo, Venturin, and Higashikawa (2009), the production capacity of a small farm is achieved at first by planting with denser spacing compared with broader plantings. However, the initial differences of production tend to decrease over the years, although they become similar when the plants with more space completely use the available natural resources, which results in equivalent production per area for all spacings ofthe planting (Berger, Schneider, Finger, & Haselein, 2002). Therefore, because ofthe huge spacings between eucalyptus rows in the present study, the production capacity of small farms has not yet been reached, which is highlighted by the similarity of wood productivity per tree between treatments.
It should be noted that the symbol * indicates that the animal reached the necessary weight for slaughter. In relation to the ‘weights’, and as mentioned above, it is possible to establish a physiological criterion based onthe adaptation and development of each crop in a given area and a particular period, from which values between zero and one can be allocated to each crop, indicating the percentage advantage of that crop in relation to the other crops when it is grown in that plot and during that period. Table 2 shows which animals have a live weight below that for slaughter; a value of one (1) indicates that the live weight ofthe animal is below that for slaughter, and a value of zero (0) indicates that the animal has reached the weight for slaughter.
ABSTRACT: This study aimed to evaluate the production characteristics of pastures in inte- grated livestock production systems. For that, an experiment was carried out in São Carlos, SP, Brazil, from 2013 to 2015. Forage development, production and nutritive value were evaluated in five beef cattle production systems: extensive continuous stocking (Urochloa decumbens) = EXT; intensive = INT; crop-livestock = iCL; livestock-forest = iLF andcrop-livestock-forest = iCLF. Rotational stocking pastures in INT, iCL, iLF and iCLF systems were established with Urochloa brizantha cv. BRS Piatã. In iCL and iCLF, pastures were renovated by resowing the grass simulta- neously with corn. In iLF and iCLF, eucalyptus (Eucalyptus urograndis clone GG100) was planted in Apr 2011 in single rows with 15 × 2 m spacing. In the 2013/2014 crop season, INT, iCL, and iCLF pastures were more productive than in iLF and EXT. Shading increase in the 2014/2015 season reduced pasture production in iLF and iCLF, compared with INT and iCL, but increased crude protein content and digestibility. In the shaded systems, pasture production was affected by proximity to trees, mainly due to reductions in solar radiation transmission. The principal component analyses showed that forage accumulation and leaf area index were associated with the position in the middle ofthe inter-row, and nutritive value was associated with the position at 1.5 m from thetrees. In iCLF, solar radiation transmission greater than 60 % maintained forage accumulation similar to iCL, while in iLF, it reduced forage accumulation, evidencing that pasture renovation minimized shading effects in these systems.
ABSTRACT: Viticulture is an activity of great social and economic importance in the lower-middle region ofthe São Francisco River valley in northeastern Brazil. In this region, the fertility of soils under vineyards is generally poor. To assess theeffectsof organic andnitrogen fertilization on chemical properties and nitrate concentrations in an Argissolo Vermelho-Amarelo (Typic Plinthustalf), a field experiment was carried out in Petrolina, Pernambuco, on Syrah grapevines. Treatments consisted of two rates of organic fertilizer (0 and 30 m 3 ha -1 ) and five N rates (0, 10, 20, 40, and 80 kg ha -1 ), in a randomized block design arranged in split plots, with five replications. The organic fertilizer levels represented the main plots andthe N levels, the subplots. The source of N was urea andthe source of organic fertilizer was goat manure. Irrigation was applied through a drip system and N by fertigation. At the end ofthe third growing season, soil chemical properties were determined and nitrate concentration in thesoil solution (extracted by porous cups) was determined. Organic fertilization increased organic matter, pH, EC, P, K, Ca, Mg, Mn, sum of bases, base saturation, and CEC, but decreased exchangeable Cu concentration in thesoil by complexation of Cu in the organic matter. Organic fertilization raised the nitrate concentration in the 0.20-0.40 m soil layer, making it leachable. Nitrate concentration in thesoil increased as N rates increased, up to more than 300 mg kg -1 in
We have provided an abbreviated survey ofthe potential impacts (risks and benefits) of GRCs onsoiland water quality. Clearly, we and many ofthe authors who have written on this topic empha- size that risks and benefits of any GRC are very geography and time dependent. For example, increasing GR weeds in GRCs are changing how farmers use these crops, and in most cases reduc- ing the environmental benefits of GRC systems. Glyphosate is more environmentally and toxicologically benign than many ofthe herbicides that it replaces. Its effectsonsoiland water are relatively small. Soil erosion caused by tillage results in long-term environmental damage. Being a broad-spectrum, foliarly applied herbicide, with little or no activity in soil, glyphosate is highly com- patible with reduced- or no-tillage agriculture and has contributed to the adoption of these practices in the Western Hemisphere. This contribution to environmental quality by GRCs is perhaps the most significant one. Numerous regulatory tests of glyphosate and glyphosate products, using rigorous protocols meeting inter- national standards, as well as product post-marketing surveillance, have failed to reveal any effects that could help substantiate any claims of adverse health and environmental outcomes. 102
Seasonal mean values used in this study were calculated from the monthly mean values, which were first averaged from all measurements in the same month. Repeated measures ANOVAs were used to examine the temporal (inter- or intra-annual) variations andtheeffectsof warming and N addition onsoil N mineralization, soil temperature, soil water content, soil total PLFAs, fungal PLFAs, B: F, MBN, AN, C: N, and above- and belowground plant N content. Between-subject effects were evaluated as warming, N addition, and their interactions, and within-subject effects were year (or measuring times within season) and its interactions with warming or N addition. Stepwise multiple linear analyses were used to determine the relationships ofsoil NMR (or soil NNR) with control factors. Statistical analyses were conducted using SPSS (SPSS 11.0 for windows, USA).
four replicates. The treatments consisted of three organic fertilizers (poultry litter, pig slurry, and compost) and two mineral fertilizers (M1, equivalent to pig slurry; and M2, equivalent to poultry litter) in interaction with three application rates, corresponding to 75, 100, and 150 % ofthe fertilizer recommendation for thecropof interest and a control (with no fertilizer). Soil sampling was performed in the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m layers for determination ofthe phosphorus fractions. Successive use of organic or mineral fertilizers for six years in the iCL system considerably raises the labile and moderately labile P fractions up to the 0.20 m depth and, with less intensity, raises the non-labile fractions up to the 0.10 m depth. Thesoil P increase associated with fertilizer input raises soybean and corn yields, and it does not exceed the critical P limit according to local environmental legislation.