Effects of bio-organic fertilizers on soil organic carbon components and biomass of shamrock

Effects of bio-organic fertilizer to organic carbon (SOC), dissolved organic carbon (DOC), easy oxidation of organic carbon (ROC), microbial biomass carbon (MBC) and Shamrock biomass were studied. The results showed that the contents of SOC, DOC, ROC, MBC could be significantly increased by bioorganic fertilizer. When cultured for 180d, SOC and DOC increased by 42~154 and 9~40%, respectively, compared with T0 treatment. ROC and MBC content increased by 38~173 and 4~9%, respectively. In addition, with the increase of the application of bio-organic fertilizer, the SOC and DOC contents increased. In T4 treatment, the SOC and DOC contents were the highest, which were 25.05 g/kg and 74.89 mg/kg, respectively. In T3 treatment, the ROC and MBC contents were the highest, 9.84 g/kg and 167.09 mg/kg, respectively. Compared with the initial incubation period, SOC decreased by 6~17%, DOC increased by 3~13%, ROC and MBC increased by 15~64, 3~25%, respectively. The application of bio-organic fertilizer increased the aboveground and underground biomass and the highest value were in the T2 and T3 treatments, respectively. The application of biological organic fertilizer increased the content of active organic carbon components. Results of the present study provide evidence for the application of biological organic fertilizer in the agricultural area of China. Bangladesh J. Bot. 50(3): 911-916, 2021 (September) Special

Parameters of radish phytomass (Raphanus sativus L.) determined by vermicompost and earthworms (Eisenia fetida)

In 2-year outdoor pots experiment, which was realised in the vegetation cage situated in the campus of Slovak University of Agriculture in Nitra, both the impact of different doses of vermicompost (Vc) (0%, 10%, 20%, 25% and 50%) and the number of earthworms (EW) (0, 10 and 20 individuals/pot) in the soil substrate were studied on the quantitative and qualitative parameters of radish yield. The achieved results show that along with the increasing quantity of Vc, the total chlorophyll content also increased proportionally. The content of vitamin C declined and the content of nitrates increased in both the aboveground and underground biomass. The weight of the roots and leaves of radish increased until the content of Vc in the substrate did not exceed 20%. Vermicompost abundance >20% led to the decline of root and leaf biomass formation. The root yield and leaf biomass were higher in the presence of 50% Vc content in the substrate, compared with the control. The EW had mostly a negative impact on radish phytomass formation, particularly both weight and root diameter. The highest percentage of roots weight decline cultivated in the treatment with EW were obtained with the least dose of Vc (10%), thereby the least quantity of fodder for the EW. The impact of EW on the total chlorophyll, vitamin C and nitrates contents in roots and leaves was non-significant. The number of EW did not influence the root diameter and content of vitamin C; however, it affected the root weight.

Evaluation and modeling of factors influencing the depth of mixing layer in which soil solute releasing from soil to surface runoff

The depth of mixing layer is one of the important parameters which cannot be assigned a constant value affected by many factors in the slope runoff. The objective of this study was to investigate the effect of slope length and underground biomass on slope runoff, solute transport processes, as well as mixing layer depth. In this study, the experimental plots with the four slope lengths (5, 10, 15, and 20 m) and a width of 2 m were built on the slope with the gradient of 20°. In addition, the plots with the millet or wheat planting were built on the slope. The change of runoff and solute transport was analyzed through simulated rainfall experiments and then to estimate mixing layer depth. The results showed that the runoff rate decreased and more runoff seeped into the slope soil with increasing slope length. Increasing underground biomass also promoted greater rainfall infiltration into the soil. The increase in slope length increased the concentration of solute in runoff, but more underground biomass reduced the nutrients transported with runoff. The effective mixing depth increased with an increase in slope length, but effective mixing depth decreased with increased underground biomass. The modified expression of the equivalent mixing model under different slope lengths and underground biomass could accurately describe the solute transfer process in runoff when compared with complete mixing model and incomplete mixing model based on exponential functions. This research provided a reference for improving the application of mixing layer models in the slope management.

90Sr and 137Cs inventories in the depots and biogenic fluxes of the typical forest stands in the Chernobyl exclusion zone

The paper reports results of the study of depots and biogenic fluxes of 90Sr and 137Cs in the typical coniferous (Scots pine) and deciduous (Silver birch) forest ecosystems of the Chernobyl Exclusion Zone during 2016 - 2018. Data on activity concentrations and shares of the total activity of the studied radionuclides in the components of aboveground and underground biomass and their vertical distributions by 10 cm layers of the soil profile up to a depth of 1 m are presented. The downward and upward fluxes of 90Sr and 137Cs activity (including the processes of their deposition as a result of growth and formation biomass) are calculated in annual terms. Significantly higher 90Sr mobility in elements of forest ecosystems than 137Cs is confirmed. The estimated flux values for the investigated forest areas indicate a gradual further increase in the share of these radionuclides in the aboveground biomass components (up to 0.9 %·year-1 from the total activity in forest ecosystems) owing to the increase of organic matter stocks.

Production and Some Energy Indicators in Semi-desert Biogeocenosis of the Ganikh-Airichai valley of Azerbaijan

The results of phytoproductivity in dynamics and some energy indicators of Artemisetum–Ephemerosum and Alhagietum–Artemisosum on the territory of the Ganykh–Airichai valley of Azerbaijan are presented. These are typical semi-desert cenoses. Analysis of quantitative indicators of energy consumption in plant communities over the period of research showed that 2 types of weather and climatic conditions determined 2 contrasting periods of development. Data on the aboveground and underground biomass in the studied communities are given. A comparative analysis has been carried out.

Inoculation of Pseudomonas putida in Farmer Environment to Improve Growth and Yield: Maize (Zea mays L.) Trial in Sothern, Central and Northern (Benin)

The application of Plant Growth Promoting rhizobacteria as a microbial bio-fertilizers to increase soil fertility and productivity, allows a rational use of chemical fertilizers which makes agriculture sustainable. The aim of this study was to evaluate the effects of the rhizobacteria Pseudomonas putida on the maize productivity in farmer environment. For this purpose, trials were conducted in two Agricultural Development Poles with nine (09) producers equitably distributed in Southern, Central and Northern Benin. The experimental design was a completely randomized block of three (03) treatments (T1: farmer practice; T2: P. putida + ½ recommended dose of NPK and Urea; T3: recommended dose of NPK and Urea) with three (03) repetitions. During sowing, two (2) maize seeds of the 2000 SYNEE-W variety were introduced into a pot and inoculated with 10 ml of bacterial suspensions of 108 CFU/ml concentration. The results showed that the best heights, stem diameters and leaf areas of maize plants were obtained with P. putida + ½ recommended dose of NPK and Urea with the nine (09) producers of the three (03) areas with respective increases of 14.76%; 18.08% and 26.56% compared to the farmer practice. In addition, the results related to yield parameters such as aerial biomass, underground biomass and maize grain yield were better improved with the P. putida + ½ recommended dose of NPK and Urea. The average rates of increase recorded were 42.70%, 38.96% and 77.69%, respectively, compared to farmer practice. In sum, this rhizobacteria can be used as the microbial bio-fertilizers to improve maize productivity in Benin.

Carbon content in a system of avocado production (Persea americana Mill) in Pillco marca - Huánuco - 2018.

The investigation was carried out in a system of avocado production (Persea americana Mill) var. Has and strong, politically located in the Center for Fruit and Fruit Research (CIFO) - Huanuco. In order to determine the content of organic carbon (COS) at three depths of the soil and estimate the carbon fixed in the aerial and underground biomass of avocado plants by using allometric equations. The methodology used for the field sampling process of probabilistic COS in its Composite Random Sampling form, while for aerial and underground biomes in its optimal stratified sampling form. It was determined that the storage of total organic carbon in the soil by surface between plant and under the tree from 0 to 10 cm deep presents the lowest tendency to store less carbon 9.45 and 10.37 t C/ha respectively. However, as soil depth increases, the rate of organic carbon fixation in the soil tends to increase 17.79 and 10.98 t C/ha from 20 to 30 cm deep. As well as the area and underground biomass of the avocado plants of 7 years of age. The avocado evaluated reached storing 30,239 t C/ha in the aerial biomass and 6,918 t C/ha in the underground biomass. The carbon fixation rate in avocado plants to date stores 5,308 t/ha in total biomass. Keywords: Organic carbon, soil, storage, biomass, fixation rate.