RESUMO
Assessing the spatial distribution of organic matter and total nitrogen in soil is essential for management and optimum utilization of fertilizers. Therefore, the present field experiment was conducted to evaluate the impact of different planting pattern arrangements on the spatial distribution of soil total nitrogen and organic matter content under a maize/soybean strip relay intercropping system. The planting was arranged in a manner such that soil sampling could be done from continuous maize/soybean relay strip intercropping (MS1), maize/soybean relay strip intercropping in rotation (MS2), traditional maize/soybean intercropping (MS3), sole maize (M), sole soybean (S), and fallow land (FL) from 2018 to 2020. The results showed significant variations for soil organic matter and total nitrogen content under different planting pattern arrangements of maize and soybean in the strip relay intercropping system. Across all systems, the highest soil organic matter (29.19 g/kg) and total nitrogen (10.19 g/kg) were recorded in MS2. In contrast, the lowest soil organic matter (1.69 g/kg) and total nitrogen (0.64 g/kg) were observed in FL. Soil organic matter and total nitrogen in MS2 increased by 186.45% and 164.06%, respectively, when compared with FL. Soil organic matter and total nitrogen in MS2 increased by 186.45% and 164.06%, respectively, when compared with FL. Furthermore, under MS2, the spatial distribution of soil organic matter was higher in both maize and soybean crop rows as compared with other cropping patterns, whereas the soil total nitrogen was higher under soybean rows as compared with maize in all other treatment. However, correlation analysis of the treatments showed variations in organic matter content. It can be concluded that different planting patterns can have varying effects on soil organic matter and total nitrogen distribution under the strip relay intercropping system. Moreover, it is recommended from this study that MS2 is a better planting pattern for the strip relay intercropping system, which can increase the spatial distribution of soil organic matter and total nitrogen, thereby improving soil fertility, C:N ratio, and crop production. This study will serve as a foundation towards the scientific usage of chemical fertilizers in agricultural sector.
RESUMO
Epidemiologic, clinical and imaging data were collected from 14 children with confirmed coronavirus disease 2019 (COVID-19) admitted in Beijing Ditan Hospital from January 27, 2020 to February 12, 2020. There were 6 boys and 8 girls with a median age of 3.5 years (6 months-9.4 years). Four patients had a history of travel to Wuhan City or Hubei Province and 2 patients had contacted with people from Wuhan; 13 patients were familial cluster of infection. The incubation period was 4 to 16 days. The clinical manifestations were fever in 8 cases, cough in 5 cases, diarrhea in 1 case; and 2 cases were asymptomatic. Four patients had abnormal peripheral blood routine, including 1 had lymphocytosis, 3 had lymphocytopenia; 3 patients had a slightly elevated CRP, and 3 patients had hepatic dysfunction. Thirteen patients underwent chest CT; and 1 case showed bilateral lung glass exudation, 1 case showed multiple patchy high density shadows of bilateral lung. One patient underwent chest X-ray examination, which was showed no abnormal findings. The pediatric patients with COVID-19 in this series generally have a traceable epidemiological history. The clinical manifestations are fever, cough and diarrhea. Peripheral white blood cell counts were most normal. Chest CT reveals less severe changes than those in adults, most child patients show no manifestation of pneumonia.
