Wednesday 16 January 2019

Bauxite mining remediation

Should this be of interest to Malaysian federal and Kuantan state govt. agencies. But does anyone care about soil and land restoration in Kuantan?

Aged biochar alters nitrogen pathways in bauxite-processing residue sand: Environmental impact and biogeochemical mechanisms


"Low nitrogen (N) content and retention in bauxite-processing residue sand (BRS) disposal areas pose a great challenge to the establishment of sustainable vegetation cover in this highly alkaline environment. The budget and fate of applied N in BRS and its potential environmental impacts are largely unknown. We investigated the effect of combined application of biochars [aged acidic (AC) vs alkaline pine (PC)] and di-ammonium phosphate (DAP) fertiliser on ammonia (NH3) volatilisation, nitrous oxide (N2O) emission and N retention in a 116-day glasshouse study. The application of AC to BRS decreased pH (≈0.5 units) in BRS, while PC biochar increased pH (≈0.3 units). The application of AC reduced NH3 volatilisation by ca. 80%, while PC by ca. 25%. On the other hand, the AC treatment increased N2O emission by 5 folds. However, the N loss via N2O emission in the AC treatment only accounted for ca. 0.4% of applied N. The reduction in BRS pH and increased retention of mineral N due to the presence of oxygen-containing (phenolic and carboxylic) functional groups in AC may be responsible for reduced NH3 volatilisation and increased N2O emission. This study has highlighted the potential of biochar (particularly aged biochar) in improving N retention and minimising environmental impacts in highly alkaline environments."


Sunday 6 January 2019

Rice straw biochar reduces N loss








Ammonia (NH3) volatilization is a major loss of nitrogen fertilizer in paddy fields. The incorporation of straw or biochar has been considered to be the alternative options for soil improvement and agriculture sustainability. A field experiment was conducted to evaluate the potential role of rice straw and rice straw derived biochar in controlling NH3 volatilization according to the conventional nitrogen fertilizer level (urea, 270 kg N ha−1) during one rice (Oryza sativa L., cv. Xiushui134) growing season. Four treatments comprised rice straw at the rate of 8 t ha−1 (RS); rice straw derived biochar at the rate of 2.8 t ha−1 (RSBL); rice straw derived biochar at the rate of 22.5 t ha−1 (RSBH) and a control (CK). Compared to straw application, biochar incorporation reduced the cumulative NH3 volatilization (about 20%) from paddy fields significantly (p < 0.05), promoted rice yields and plant N aboveground as well as increased the abundance of ammoxidation amoA genes. In contrast with control, the ratios of NH3-N and total N input for RS, RSBL and RSBH declined significantly 4.15%, 4.40% and 11.12%, respectively (p < 0.05). Reduced NH3 volatilization in RSB treatments were mainly attributed to the decrease of NH4+-N concentration in the surface water, which could resulted from the enhancement of rice growth and the promotion of ammonia oxidation in soil. The increase of soil pH and soil CEC with biochar amendment played an important role on nitrogen retention and nitrogen cycle in soil. These results indicated that the incorporation of rice straw derived biochar instead of rice straw could be a promising approach to control NH3 volatilization and improve rice yield.

Biochar enhances animal growth

Effect of biochar on growth performance of local “Yellow” cattle fed ensiled cassava roots, fresh brewers’ grains and rice straw

Bounthavy Vongkhamchanh, T R Preston[1], R A Leng[2], Le Van An[3] and Duong Thanh Hai[3]

Faculty of Agriculture and Forestry, Champasack University, Champasak, Lao PDR
1 Centro para la Investigación en Sistemas Sostenibles de Producción Agropecuaria (CIPAV), Carrera 25 No 6-62 Cali, Colombia
2 University of New England, Armidale NSW, Australia
3 Faculty of Agriculture and Forestry, Hue University, Vietnam


In a 56-day experiment with 6 local Yellow cattle fed ensiled cassava root-urea, brewers’ grains and rice straw, there were indications (p=0.08) that after an initial 4-week adaptation to the diet, the cattle were growing faster when 1% of biochar (derived from rice husk) was incorporated in the diet.

Friday 4 January 2019

Apologies to all who have posted comments

I've just discovered 57 comments awaiting moderation!
I did not have blogger configured properly (to get notice of a comment).
Some comments dated back to 2016!
Fixed now.
Humble apologies from the hopeless editor.