https://commons.ufh.ac.za/vital/access/manager/Index en-us 5 https://commons.ufh.ac.za/vital/access/manager/Repository/vital:35091 Wed 12 May 2021 20:17:55 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:35211 drum biochar> control. Also, the two maize biochar types significantly (p< 0.05) increased the release of cations namely Ca, Mg and Na however, some decrease in nutrient concentrations were observed due to increase in pH levels at the later stage of the study. Biochar incorporation increased extractable P release from 30- 40 mg P/kg to an average range of between 120- 160 mg P/kg across all soil types. A glasshouse study was also conducted investigating the effect of different biochar rates of the two maize biochar types used in the previous studies on early maize growth and nutrient uptake, same soil types were used as those in the incubation study. Biochar was applied at application rates of 0, 100, 200 and 300 kg C/ha of biochar. The glasshouse experiment consisted of two cycles, each with a six week period of monitoring maize seedling growth development. Generally, a significant increase in maize growth parameters such as plant height, stem girth, number of leaves and leaf area increased after biochar additions compared to the control. Both biochars significantly improved maize seedling growth at an application rate of 200 kg C/haHowever, the two biochar types displayed varying impacts on maize growth due to influence of soil type and biochar application rates. Nutrient- uptake of Ca, P, Na and Mg showed to improve at an application rate of 200 kg C/ha for both biochar types showing a 50 percent increase compared to the control. Nutrient- uptake patterns for P, Ca, Mg and Na differed across all soil types, mainly due to changes in pH and Na levels which were influenced by increased biochar concentrations resulting in nutrient deficiency. Another glasshouse experiment aimed at investigating the effects on the two maize biochar types on influencing the effectiveness of both organic and inorganic fertilizers for improved early maize growth and soil productivity. Biochar was applied at an application rate of 400 kg C/ha of biochar, fertilizer was applied at application rates of 0, 10, 20, 30 and 40 kg N/ha and manure at 0, 10, 20, 30 and 40 t/ha respectively. The glasshouse experiment consisted of two cycles, each with a six week period of monitoring maize seedling growth development. In the 1st cycle, manure rate of 40 t/ha resulted in the highest plant height of maize seedlings grown in the glasshouse, biochar type also showed to influence plant height. After the 1st harvest Mg, K and P levels improved at 30 t/ha, Na at 20 t/ha and Ca 40 t/ha of manure. Plant height and stem girth improved at 30 kg N/ha of fertilizer, however, nutrient levels for Ca, K and Mg decreased after the 1st harvest, while Na levels increased. Nutrient uptake was the highest for Mg and Na at 40 kg N/ha while for Ca at 30 kg N/ha of fertilizer. During the 2nd cycle plant height was the highest at 30 t/ha of manure, and effect of manure rate was significant (p<0.05) for number of leaves, plant height and biomass. Whereas, manure rate and biochar type effect were insignificant (p>0.05) for pH, Ec and nutrient uptake changes. Maize seedling showed significant response to fertilizer 40 kg N/ha for most of the growth parameters measured (P<0.05), except for germination percentage. All treatments investigated had no effect on germination percentage. The two biochar types showed significant (p<0.05) effects on soil pH and Ec. Drum biochar was slightly better performing than pit biochar. Results obtained from the various studies suggests that maize biochars derived from the pit and drum pyrolytic systems are potential soil amendments in correcting soil acidity and nutrient deficiency in the EC Province. Both biochar types have shown abilities to improve early maize growth and effectiveness of fertilizers in maize based systems of the EC Province. However, some variations in soil fertility and early maize growth were observed as a result of the soil type response towards the two biochar applications. This could also have risen as a result of a number of factors such as the nutritional composition of biochar material, initial soil type chemical composition, biochar and fertilizer application rates and time taken or period to complete each study. Therefore, further experiments should be conducted to validate these results, preferable having longer periods of study, moreover, field experiments. In addition, investigations on potential feedstock materials such as animal wastes used as biochar in the EC Province can be conducted.]]> Wed 12 May 2021 17:55:08 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:28144 Thu 13 May 2021 07:09:23 SAST ]]> https://commons.ufh.ac.za/vital/access/manager/Repository/vital:39659 0.05) on soil bulk density (ρb) and porosity whereas a significant effect on soil water content under NT was observed. Crop rotation had no significant effects (p > 0.05) on soil bulk density, porosity and soil moisture across the tillage treatments. The MWS rotation registered an increase in soil porosity in comparison with the MWM and MFM. Tillage x crop rotation interaction effects were significant (p < 0.05) on the measured porosity and soil water content. Soil bulk density showed negative correlation with soil porosity and soil water content (SWC) whereas porosity had a positive correlation with SWC. On yield parameters, results revealed that no significant (P>0.05) interaction of main effects with respect to wheat biomass and grain yield. Tillage had a significant (P<0.05) effect on wheat biomass only in season 2. Tillage and crop rotation effects were not significant (P>0.05) with regards to grain yield throughout the experimental period. Higher grain wheat biomass and grain yield were found in MWS rotation under NT with surface residue retention although not statistically significant. Correlation analysis revealed that wheat yield was positively correlated to SOC, P, and Total N. Therefore, combination of NT with MWS rotation with residue retention has the potential to significantly improve soil chemical properties and wheat grain yield whereas MWM followed by MWS crop rotation under NT showed an increase in soil porosity and soil water content.]]> Thu 13 May 2021 06:56:56 SAST ]]>