Globally, the rate of land-use change (LUC) is increasing rapidly to support biofuel feedstock production. In Brazil, sugarcane (Saccharum officinarum) expansion to produce ethanol is displacing ...degraded pastures. Intensive mechanization for sugarcane production, could impact soil physical quality in these areas. We evaluated a typical LUC sequence (i.e., native vegetation–pasture–sugarcane) on soil physical quality at three sites in the central-southern region of Brazil. The soil physical properties evaluated through on-farm and laboratory soil analyses were: bulk density, degree of compactness, macroporosity, microporosity and total porosity, water-filled pore space, indexes of soil water storage and aeration capacity, soil resistance to penetration, field-saturated hydraulic conductivity and stability structural index. Calculations of mean weight diameter for the soil aggregates and soil physical quality ratings from a visual evaluation of soil structure (VESS) were also included in this study. From those data we defined a minimum dataset for calculating an additive soil physical quality index (SPQI). Long-term conversion from native ecosystems to pasture increased soil compaction (i.e., higher bulk density, degree of compactness and resistance to penetration values), decreased aeration porosity and water hydraulic conductivity, and consequently, created an unbalanced ratio between water- and air-filled pore space in the soil. Based on our SPQI, the soil's capacity to perform its physical functions decreased from 90% under native vegetation to 73% under pasture. Land-use change from pasture to sugarcane induced slight soil physical quality degradation, in which soil function was 68 and 56% of capacity. Overall, soil physical quality decreased under sugarcane fields, due to decreases in soil porosity, aeration and water hydraulic conductivity as well as increases in soil penetration resistance, structural degradation and erosion risk. Tillage operations performed during the sugarcane replanting (~5years) had a short-term positive effect on soil physical quality, although over time it further decreased the resistance to erosion and structural degradation. Therefore, to convert degraded pasture to sugarcane in a sustainable manner, the soils should be managed in ways that increase the soil organic matter and minimize compaction. These actions are needed to prevent further soil physical quality degradation and to improve both economic and environmental sustainability of sugarcane ethanol production.
•We assessed soil physical changes due to land use change for sugarcane production in Brazil.•Soil physical quality decreased from native vegetation (90%) to pasture (70%) to sugarcane (56 to 68%).•Soil compaction limits soil aeration and water availability under pasture and sugarcane.•Soil tillage in sugarcane fields had short-term positive effects over soil compaction.•Sugarcane soils are more susceptive to degradation by erosion process.
Cellulosic ethanol derived from sugarcane straw may have a significant role to play in the projected increase of Brazilian biofuel production for next years. However, some practical challenges, such ...as, defining how much and how to recover straw from the field still need to be overcome. Integrated sugarcane harvesting (i.e. stalks plus straw) with straw separation at the processing site has shown greater cost-effectiveness. However, there is no published procedure to quantify the yield of sugarcane straw, to set up the harvester to collect only a specific portion of this straw or to verify the quantity of straw left in the field. We conducted four field trials in the southeast of Brazil to develop systematic field guidelines that describe how to estimate the yield of sugarcane straw, the harvester setup to vary the amount of straw left in the field and how to evaluate the overall performance of the operation. The results showed that these guidelines were efficient (r2 ≥ 0.97, p < 0.01) and, therefore, can be incorporated into a standard protocol to help the sugarcane industry improve the efficiency of the sugarcane straw harvesting process for bioelectricity cogeneration and cellulosic ethanol production.
•A step-by-step protocol to guide sugarcane straw recovery from the field was proposed.•Integral sugarcane harvest (stalks + straw) with straw separation in the industry.•Setting combinations between primary and secondary extractor fans of the sugarcane harvester.•The procedure was efficient to leave the desired amount of sugarcane straw in the field.
Native vegetation clearing in the Amazon Cerrado region for agricultural purposes may be modifying soil chemical characteristics. The extent of change depends on the management practices used. We ...evaluated changes in chemical properties of a clayey oxisol (dystrophic red yellow latosol) under no-tillage (NT) and conventional tillage (CT). Soil samples were taken randomly (
n
=
5) in July 2004 at 0–5
cm, 5–10
cm, 10–20
cm and 20–30
cm depths at six treatments: Cerrado with native vegetation, CT cultivated with rice for 1 year (1CT) and 2 years (2CT), and NT cultivated with soybean for 1 year (1NT), 2 years (2NT) and 3 years (3NT) in each case after a 2-year period of rice under CT. Soil pH (CaCl
2, KCl and water), ΔpH, total acidity (H
+
+
Al
3+), total organic carbon (TOC), available P, exchangeable K, Ca, Mg, potential cation exchange capacity (CEC) and base saturation (V) were determined. The highest pH values were determined in topsoil layers at the older NT adoption. Under Cerrado pH was lower than under cultivation at all depths due to absence of lime application. Generally, negative values of ΔpH were observed at all sites in all layers indicating predominant presence of negative charges in the soil. Although not statistically significant it seems that the amount of negative charges was higher in deeper layers. Total acidity displayed the highest values throughout the soil profile under Cerrado and low pH and low concentrations of exchangeable bases. Cultivated systems with fertilizer generated considerable increases of P, K, Ca, and Mg compared to Cerrado. Soil macronutrient content and base saturation under NT gradually increased throughout the profile with time. Highest CEC values were calculated for the 0–5
cm and 5–10
cm layers under Cerrado and NT systems. For the 0–5
cm layer CEC was lower at the CT system compared to the Cerrado and the oldest year under NT system.
Alteration of TOC was more pronounced in the top 10
cm layer at all sites. The highest content was measured in the topsoil layer under Cerrado. Considering the future land use in Cerrado areas the NT system, if properly managed, appears to be the favourable management option of the existing croplands established after Cerrado clearing.
Due to environmental issues, many methods of exploiting renewable natural resources are alternatives to reduce the dependence on non‐renewable agricultural inputs. Phosphate fertilization on ...weathered tropical soil and waste reuse, for example, requires better management strategies. Thus, biochar from organic residues can be a strategy to reduce pressure on natural resources, in addition to having the potential to mitigate climate change. This study aimed to evaluate the availability of P in tropical soils from the interaction of biochar and arbuscular mycorrhizal fungi (AMF) in the aboveground and root systems of the plant and its impact on greenhouse gas (GHG) emissions. The results indicated that the addition of biochar was an alternative for C sequestration and GHG mitigation, causing no damage to the plant. The applied biochar amount had, for the most part, emission equal to or less than the control treatment (soil only). The sugarcane straw biochar (BCS) showed higher emissions, mainly in the presence of P and AMF. Biologically speaking, there was no significant effect in the presence of mycorrhizae. However, with regard to plant production, treatments where mycorrhizae were inoculated, longer and wider leaves were found. In the production of maize (Zea mays L.) plant material (aboveground and root), the upper and lower values were related to the poultry manure biochar (BPM) , and the presence of P, the values were lower, indicating that, for the good development of the plant, only the presence of the biochar is sufficient, without requiring the addition of phosphate fertilizer.
Animal production systems are important sources of greenhouse gases (GHGs), especially methane (CH₄) and nitrous oxide (N₂O). GHG emissions from urine patches have been extensively studied in ...temperate climates, with few studies under tropical conditions. Here we examined the driving factors of N₂O and CH₄emission from urine patches in the tropics, as well as the role of the nitrification inhibitor DCD (dicyandiamide) in mitigating emissions. We hypothesized that the high temperature and periodical rainfall can increase GHG emissions from urine patches through accelerating mineralization of urine-N. We measured CH₄and N₂O emissions from beef cattle urine (360 kg N ha⁻¹) in Rondônia state (Brazil, tropical climate), during two different seasons (winter and summer), with and without the application of DCD (10 kg ha⁻¹). No effects of DCD on cumulative N₂O emissions were detected in summer, but DCD retarded the main emission peak. During winter DCD increased N₂O emissions from 10.8 to 39.2 mg N–N₂O m⁻²(p ≤ 0.05). Emission factors averaged 0.4 % for summer and 0.1 % for winter, which is significantly lower than the IPCC default value of 1 %. The climate, associated with soil (acidic pH, WFPS and low N content) and plant properties (biological nitrification inhibition) resulted in a low emission factor. We concluded that the IPCC default emission factor for tropical systems may be reduced, and that the application of DCD is not recommended in such systems.
Allogeneic hematopoietic stem cell transplantation (HSCT) is still needed for many children with very high-risk acute leukemia. An HLA-haploidentical family donor is a suitable option for those ...without an HLA-matched donor. Here we present outcomes of a novel HLA-haploidentical HSCT (haplo-HSCT) strategy with adoptive immunotherapy with thymic-derived CD4
CD25
FoxP3
regulatory T cells (Tregs) and conventional T cells (Tcons) performed between January 2017 and July 2021 in 20 children with high-risk leukemia. Median age was 14.5 years (range, 4-21), 15 had acute lymphoblastic leukemia, 5 acute myeloid leukemia. The conditioning regimen included total body irradiation (TBI), thiotepa, fludarabine, cyclophosphamide. Grafts contained a megadose of CD34+ cells (mean 12.4 × 10
/Kg), Tregs (2 × 10
/Kg) and Tcons (0.5-1 × 10
/Kg). All patients achieved primary, sustained full-donor engraftment. Only one patient relapsed (5%). The incidence of non-relapse mortality was 15% (3/20 patients). Five/20 patients developed ≥ grade 2 acute Graft versus Host Disease (aGvHD). It resolved in 4 who are alive and disease-free; 1 patient developed chronic GvHD (cGvHD). The probability of GRFS was 60 ± 0.5% (95% CI: 2.1-4.2) (Fig. 6), CRFS was 79 ± 0.9% (95% CI: 3.2-4.9) as 16/20 patients are alive and leukemia-free. The median follow-up was 2.1 years (range 0.5 months-5.1 years). This innovative approach was associated with very promising outcomes of HSCT strategy in pediatric patients.
Biofuels are fundamental for meeting societal energy needs within the next few decades, but the sustainability of large-scale land use conversions to supply feedstock crops remains unclear. ...Quantitative data documenting how biofuel crop expansion will affect ecosystem services (ES) is needed to develop sustainable energy policies. Using pairwise comparisons of published and novel environmental, social and economic indicators, we quantitatively assessed the provision of critical ES related to key aspects of the sustainability of pasture-to-sugarcane transitions in Brazil. We found that with the exception of maintaining biodiversity, conversion of pasturelands to sugarcane fields enhanced many ES. Based on the Sustainability index, aimed to capture changes on key sustainability aspects by considering multiple ES and properly integrating them, we concluded that pasture to sugarcane transitions would increase the sustainability by 78% in south-central Brazil. Our results provide science-based empirical evidence that the expansion of sugarcane into degraded pasturelands is a suitable strategy to enhance Brazil's biomass feedstock supplies for producing bioenergy. Moreover, facing the complex and multidimensional concept of sustainability, our study also illustrates the importance of considering holistically land use change effects rather than individual ESs when establishing sustainable land management practices and bioenergy policies.
Except for Maintenance of biodiversity, the expansion of sugarcane over pasturelands improve many ecosystem services in areas of biofuels expansion. As result, this LUC would increase the sustainability by 78% in south-central Brazil. SOC: soil organic C. FRT: Soil fertility index. H?: Shannon?s diversity index. CYC: C cycling index. STR: Soil structural quality index. SEC: Socioeconomic index. Display omitted
•In Brazil, most of the recent sugarcane expansion has been placed over extensive pastures.•Pasture (PA) to sugarcane (SG) transitions affects key ecosystem services (ES).•Except for Maintenance of biodiversity, this land use change improve the ESs evaluated.•As result, PA-SG transitions would increase the sustainability by 78% in south-central Brazil.•Our index provides a sensitive and science-based approach for sustainability assessments.
Greenhouse gas emissions were compared with estimated carbon offsets promoted by two main changes in agricultural management in Brazil. A national greenhouse gas inventory was used to weigh the C ...sequestration potentials of replacement of conventional tillage by no-tillage and cessation of annual burning in sugar cane production. About 12.6 Mt C/yr are emitted from agricultural lands in Brazil. Continuing conversion of conventionally tilled land to no-tillage currently accumulates 9 Mt C/yr. Substitution of alcohol and bagasse from sugar cane production for fossil fuels in transportation and power generation can offset 10 and 8 Mt C/yr, respectively. Scope for sequestration of 0.53 Mt C/yr is offered by avoiding burning before sugarcane harvesting.
► FCO2 show low spatial-temporal uncertainty and high local-temporal uncertainty. ► The joint probability enables evaluate the uncertainties of temporal phenomena. ► The uncertainty allows the ...identification of areas susceptible to high emission.
The characterization of soil CO2 emissions (FCO2) is important for the study of the global carbon cycle. This phenomenon presents great variability in space and time, a characteristic that makes attempts at modeling and forecasting FCO2 challenging. Although spatial estimates have been performed in several studies, the association of these estimates with the uncertainties inherent in the estimation procedures is not considered. This study aimed to evaluate the local, spatial, local-temporal and spatial-temporal uncertainties of short-term FCO2 after harvest period in a sugar cane area. The FCO2 was featured in a sampling grid of 60m×60m containing 127 points with minimum separation distances from 0.5 to 10m between points. The FCO2 was evaluated 7 times within a total period of 10 days. The variability of FCO2 was described by descriptive statistics and variogram modeling. To calculate the uncertainties, 300 realizations made by sequential Gaussian simulation were considered. Local uncertainties were evaluated using the probability values exceeding certain critical thresholds, while the spatial uncertainties considering the probability of regions with high probability values together exceed the adopted limits. Using the daily uncertainties, the local-spatial and spatial-temporal uncertainty (Ftemp) was obtained. The daily and mean emissions showed a variability structure that was described by spherical and Gaussian models. The differences between the daily maps were related to variations in the magnitude of FCO2, covering mean values ranging from 1.28±0.11μmolm−2s−1 (F197) to 1.82±0.07μmolm−2s−1 (F195). The Ftemp showed low spatial uncertainty coupled with high local uncertainty estimates. The average emission showed great spatial uncertainty of the simulated values. The evaluation of uncertainties associated with the knowledge of temporal and spatial variability is an important tool for understanding many phenomena over time, such as the quantification of greenhouse gases or the identification of areas with high crop productivity.
Amounts and rates of C sequestration under no‐tillage are not known for a major ecological region of south Brazil. These were assessed in a Brazilian Oxisol under a plow and no‐tillage chronosequence ...located in Paraná State. The chronosequence consisted of six treatments: (i) native field (NF); (ii) 1‐yr plow conversion of native field to cropland (PNF‐1); (iii) no‐tillage for 10 yr (NT‐10); (iv) no‐tillage for 20 yr (NT‐20); (v) no‐tillage for 22 yr (NT‐22); and (vi) conventional tillage for 22 yr (CT‐22). Soil samples were collected from five depths. No‐tillage, compared with the NF treatment, caused a significant increase in soil organic C (SOC) storage. More than 60% of this increase occurred in the 0‐ to 10‐cm soil layer. There was a decrease in the amount of SOC in the CT‐22 compared with the NF soil treatment and 97% of this loss also occurred in the 0‐ to 10‐cm layer. There was a close relationship between the SOC content and the amount of crop residues input (R2 = 0.74, P ≤ 0.05). There were increased SOC concentrations in the finer particle‐size fractions (<20 μm) of no‐tillage surface soil compared with the NF or CT‐22 soils. However, the percentage of SOC derived from crop residues in no‐tillage treatments, as assessed by 13C natural abundance (δ), was generally greater in the coarse (>20 μm) than in the finer (<20 μm) particle‐size fractions. The C sequestration rate for no‐tillage was 80.6 g C m−2 yr−1 for the 0‐ to 20‐cm depth and 99.4 g C m−2 yr−1 for the 0‐ to 40‐cm depth. The no‐tillage C sequestration potential for South Brazil was estimated as 9.37 Tg C yr−1
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