This new atricle (abstract and link are below) is a MUST READ (or at least see to appreciate its details and graphs) about scientific research about biochar. My congratulations to the authors and their support teams for significant work!!!
I am (of course) delighted that TLUD-produced char (barrel style) was included among the seven (7) different char-production methods. As with virtually all good research, it raises additional questions. Be sure to note:
1. there are three (3) “biochar nutrient enrichment methods” of putting the identical nutrient mix into the test pots/plots, all dissolved in water. (See Fig. 2 and discussion in the text).
A. The water+ nutrient are used to extinguish the hot char.
B. The water+ nutrient is added to the char after the char is cold, having been quenched earlier with plain water.
C. The water+nutirient is poured onto the soil around the same time as the char is added separately.
A got the best results. B and C seem to have rather similar impact, and were only somewhat better than just adding the nutrients to the control soil.
But (I believe) that these results are from only ONE plant-grow-harvest cycle, so any residual benefits for future growing cycles or years was not part of this experiment. (So a question to the authors is: Will the same soils be used in a second (or more) growing cycles to check for multi-cycle benefits?
2. Certainly time and budget prevented tests with all 3 (A, B, C) nutrient enrichment methods with all 7 of the different sources of char. Although remaining to be shown conclusively, the final sentence of the conclusion suggests that the methods of making char do not have much impact:
“Importantly, differences in agronomic and chemical quality between biochars generated by various technologies were small compared to differences between biochar nutrient enrichment methods.”
So, a figuratively and literally “HOT TOPIC” of future biochar research should include the confirmation (or refuting) of the “quench hot char with nutrient-enriched water” hypothesis. Quench with urine, or compost tea, or disolved nutirents, whatever. It looks promising!!
One interpretation and question: Method A has fully-dry pores in the hot char. Method B already had some regular water into at least some of those spaces. Question: What if the cooled biochar (B) had been suffocated in a container and left to cool without adding any water? Would the pores still have been open and available for a cool addition of water+nutirents? Is it the “hotness” or the “freshness — no water into the spaces” that apparently let’s that “A” char to give a better crop growth? Or some of both? Unlikely that freshness alone would result in better biochar than fresh AND hot.
Because fire-extinction by suffocation with a lid (not counting suffocation with earth) is more troublesome than quenching with water (and just add the nutrients in it), there is ample suggestion that char such as from small TLUD stoves (about 300 grams each batch) should be collected in containers with water+nutrients. An easy task for a household that uses a latrine or “potty”. Much to be considered.
Who will check this main question and related questions? The research group in Nepal, or elsewhere? It could be a laboratory experiment anywhere in the world. Thesis for a graduate student, but that will take time (years) to get an answer that is released.
Doc / Dr TLUD / Prof. Paul S. Anderson, PhD Email: email@example.com Skype: paultlud Phone: +1-309-452-7072 Website: www.drtlud.com
——– Forwarded Message ——–
|Subject:||[biochar] Biochar from “Kon Tiki” flame curtain and other kilns: Effects of nutrient enrichment and kiln type on crop yield and soil chemistry|
|Date:||Sat, 29 Apr 2017 08:22:51 -0700|
|From:||‘Tom Miles’ firstname.lastname@example.org [biochar] <email@example.com>|
This open access article shows encouraging results from the use of biochar from flame cap kilns in Nepal.
International Biochar Initiative
Read the open-access, full-text article here:
Biochar from “Kon Tiki” flame curtain and other kilns: Effects of nutrient enrichment and kiln type on crop yield and soil chemistry
Biochar application to soils has been investigated as a means of improving soil fertility and mitigating climate change through soil carbon sequestration. In the present work, the invasive shrub “Eupatorium adenophorum” was utilized as a sustainable feedstock for making biochar under different pyrolysis conditions in Nepal. Biochar was produced using several different types of kilns; four sub types of flame curtain kilns (deep-cone metal kiln, steel shielded soil pit, conical soil pit and steel small cone), brick-made traditional kiln, traditional earth-mound kiln and top lift up draft (TLUD). The resultant biochars showed consistent pH (9.1 ± 0.3), cation exchange capacities (133 ± 37 cmolc kg-1), organic carbon contents (73.9 ± 6.4%) and surface areas (35 to 215 m2/g) for all kiln types. A pot trial with maize was carried out to investigate the effect on maize biomass production of the biochars made with various kilns, applied at 1% and 4% dosages. Biochars were either pretreated with hot or cold mineral nutrient enrichment (mixing with a nutrient solution before or after cooling down, respectively), or added separately from the same nutrient dosages to the soil. Significantly higher CEC (P< 0.05), lower Al/Ca ratios (P< 0.05), and high OC% (P<0.001) were observed for both dosages of biochar as compared to non-amended control soils. Importantly, the study showed that biochar made by flame curtain kilns resulted in the same agronomic effect as biochar made by the other kilns (P > 0.05). At a dosage of 1% biochar, the hot nutrient-enriched biochar led to significant increases of 153% in above ground biomass production compared to cold nutrient-enriched biochar and 209% compared to biochar added separately from the nutrients. Liquid nutrient enhancement of biochar thus improved fertilizer effectiveness compared to separate application of biochar and fertilizer.