Enzyme activities in a sandy soil of Western Bahia under cotton production systems: short-term effects, temporal variability, and the FERTBIO sample concept.

Enzyme activities (EAs) and the FERTBIO sample concept have been increasingly adopted as a novel approach to estimate the soil quality in Brazil. However, the performance of this strategy in sandy soils of the Cerrado biome remains unclear. During 2 years, in a Cerrado's sandy soil, the short-term effects of ten different cropping systems (conventional tillage or no-tillage associated with monoculture, rotations, and/or successions) on the activities of ß-glucosidase, acid phosphatase, and arylsulfatase were studied. Issues related to annual variability and the feasibility of using the FERTBIO sample concept for soil enzymes activities were also evaluated. Soil samples were collected at three different depths (0-10 cm, 10-20 cm, and 20-40 cm) in March 2017 and February 2018. Five years since the beginning of the experiment, the presence of cover crops and no-till promoted improvements in EAs evidencing the importance of regenerative management practices for the sustainability of agroecosystems in sandy soils. Regardless of the cropping systems and depths evaluated, soil organic carbon and EAs showed low temporal variation during the 2 years of monitoring. Our results also showed that it is possible to use the FERTBIO sample concept for the Quartzipsament soils of Western Bahia, Brazil.

Transitions to sustainable management of phosphorus in Brazilian agriculture.

Brazil's large land base is important for global food security but its high dependency on inorganic phosphorus (P) fertilizer for crop production (2.2 Tg rising up to 4.6 Tg in 2050) is not a sustainable use of a critical and price-volatile resource. A new strategic analysis of current and future P demand/supply concluded that the nation's secondary P resources which are produced annually (e.g. livestock manures, sugarcane processing residues) could potentially provide up to 20% of crop P demand by 2050 with further investment in P recovery technologies. However, the much larger legacy stores of secondary P in the soil (30 Tg in 2016 worth over $40 billion and rising to 105 Tg by 2050) could provide a more important buffer against future P scarcity or sudden P price fluctuations, and enable a transition to more sustainable P input strategies that could reduce current annual P surpluses by 65%. In the longer-term, farming systems in Brazil should be redesigned to operate profitably but more sustainably under lower soil P fertility thresholds.

Spinal Cord Lesion by Minor Trauma as an Early Sign of Multiple System Atrophy.

Multiple system atrophy (MSA) is characterized clinically by parkinsonism, cerebellar, autonomic, and corticospinal features of variable severity. When the presentation is only parkinsonism, the disease might be difficult to differentiate from Parkinson's disease (PD). We present a case of an 80-year-old man with previous diagnosis of PD. One year after the diagnosis, he had a whiplash cervical trauma due to a tricycle accident caused by a hole in the road. This low-energy trauma caused an unstable C4-C5 cervical fracture with spinal cord injury, which required surgical decompression and stabilization. Neurological examination showed marked postural instability, no rest and postural tremor, finger tapping slowed on the right, spastic tetraparesis (ASIA D) - predominantly on the left side, brisk deep tendon reflexes in the upper and lower extremities, and bilateral extensor plantar response. He also presented with vertical gaze restriction, mild hypometria in horizontal saccades, moderate dysphagia, and dysphonia. As atypical parkinsonism was suspected, he underwent an MRI that revealed conjunction of findings suggestive of parkinsonian-type MSA. In our case, we hypothesize that the loss of postural reflexes, as an early manifestation of MSA, did not allow the patient to have an effective reaction response to a low-energy trauma, resulting in a more severe injury. With this case report, we speculate that the severe spinal lesions caused by minor accidents can be an early sign of postural instability, which may lead to clinical suspicion of neurodegenerative disorder manifested by postural reflexes impairment.