Biochar-Compost Interactions as Affected by Weathering: Effects on Biological Stability and Plant Growth

Biochar addition to compost is of growing interest as soil amendment. However, little is known about the evolution of material properties of biochar-compost mixtures and their effect on plants after exposure to physical weathering. This study aimed to investigate the physico-chemical characteristics of fresh and weathered biochar-compost mixtures, their biological stability and their effect on ryegrass growth. To this end, we used the contrasting stable isotope signatures of biochar and compost to follow their behavior in biochar-compost mixtures subjected to artificial weathering during 1-year of incubation. We assessed their impact on ryegrass growth during a 4-week greenhouse pot experiment. Weathering treatment resulted in strong leaching of labile compounds. However, biochar-compost interactions led to reduced mass loss and fixed carbon retention during weathering of mixtures. Moreover, weathering increased carbon mineralization of biochar-compost mixtures, probably due to the protection of labile compounds from compost within biochar structure, as well as leaching of labile biochar compounds inhibiting microbial activity. After soil application, weathered mixtures could have positive effects on biomass production. We conclude that biochar-compost interactions on soil microbial activity and plant growth are evolving after physical weathering depending on biochar production conditions.

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Integrated use of biochar and compost to improve soil microbial activity, nutrient availability, and plant growth in arid soil

Arabian Journal of Geosciences ◽

10.1007/s12517-019-4414-0 ◽

2019 ◽

Vol 12 (7) ◽

Cited By ~ 1

Author(s):

Muhammad Akmal ◽

Zubaira Maqbool ◽

Khalid Saifullah Khan ◽

Qaiser Hussain ◽

Shahzada Sohail Ijaz ◽

...

Keyword(s):

Plant Growth ◽

Microbial Activity ◽

Nutrient Availability ◽

Soil Microbial Activity ◽

Arid Soil ◽

Soil Microbial

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Ascophyllum extract application can promote plant growth and root yield in carrot associated with increased root-zone soil microbial activity

Canadian Journal of Plant Science ◽

10.4141/cjps2013-135 ◽

2014 ◽

Vol 94 (2) ◽

pp. 337-348 ◽

Cited By ~ 22

Author(s):

Mohammed Zahidul Alam ◽

Gordon Braun ◽

Jeffrey Norrie ◽

D. Mark Hodges

Keyword(s):

Plant Growth ◽

Microbial Activity ◽

Field Experiments ◽

Root Zone ◽

Maximum Yield ◽

Principal Component ◽

Soil Microbial Activity ◽

Root Yield ◽

Soil Microbial ◽

Promote Plant Growth

Alam, M. Z., Braun, G., Norrie, J. and Hodges, D. M. 2014. Ascophyllum extract application can promote plant growth and root yield in carrot associated with increased root-zone soil microbial activity. Can. J. Plant Sci. 94: 337–348. Root growth and soil microbial activity were examined in two cultivars of carrot following treatment with Ascophyllum nodosum marine-plant extract. Field experiments were established in grower-managed fields of Maverick and Pronto carrots during 2010 and 2011. Soluble Ascophyllum extract powder (SAEP) was applied weekly, bi-weekly or tri-weekly at rates of 0 (control), 0.25, 0.50, 0.75 or 1.0 g L−1 over 11 to 13 wk. Results indicate that SAEP treatment increased root yields of Maverick and Pronto by about 20 and 15%, respectively, reduced proportion of smaller roots and improved harvest index (HI). Maximum yield was found at or above 0.50 g L−1 SAEP for Maverick and at 0.75 g L−1 for Pronto. Soil microbial colony counts, respiration and metabolic activity increased following SAEP applications, but varied with SAEP rate and application frequency. Using the Biolog microbial analysis system, maximum average well colour development (AWCD), substrate diversity (H), substrate evenness (E), and substrate richness (S) responses to extract treatment generally showed successive increases at 0.50, 0.75 and 1 g L−1 SAEP at tri-weekly application frequencies. With more frequent applications, rates below 1 g L−1 led to greater microbial growth, respiration and functional activities. Principal component analysis (PCA) showed a strong relationship between carrot growth, soil microbial populations and activity parameters. These results suggest that seaweed extract application can result in an increase in soil microbial activity associated with increased yield in carrots.

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Invasive species allelopathy decreases plant growth and soil microbial activity

PLoS ONE ◽

10.1371/journal.pone.0246685 ◽

2021 ◽

Vol 16 (2) ◽

pp. e0246685

Author(s):

Tongbao Qu ◽

Xue Du ◽

Yulan Peng ◽

Weiqiang Guo ◽

Chunli Zhao ◽

...

Keyword(s):

Plant Growth ◽

Microbial Activity ◽

Invasive Plant ◽

Soil Microbial Activity ◽

Invasion Success ◽

Root Extract ◽

Total Biomass ◽

Root Extracts ◽

Soil Microbial ◽

Ground Biomass

According to the ‘novel weapons hypothesis’, invasive success depends on harmful plant biochemicals, including allelopathic antimicrobial roots exudate that directly inhibit plant growth and soil microbial activity. However, the combination of direct and soil-mediated impacts of invasive plants via allelopathy remains poorly understood. Here, we addressed the allelopathic effects of an invasive plant species (Rhus typhina) on a cultivated plant (Tagetes erecta), soil properties and microbial communities. We grew T. erecta on soil samples at increasing concentrations of R. typhina root extracts and measured both plant growth and soil physiological profile with community-level physiological profiles (CLPP) using Biolog Eco-plates incubation. We found that R. typhina root extracts inhibit both plant growth and soil microbial activity. Plant height, Root length, soil organic carbon (SOC), total nitrogen (TN) and AWCD were significantly decreased with increasing root extract concentration, and plant above-ground biomass (AGB), below-ground biomass (BGB) and total biomass (TB) were significantly decreased at 10 mg·mL-1 of root extracts. In particular, root extracts significantly reduced the carbon source utilization of carbohydrates, carboxylic acids and polymers, but enhanced phenolic acid. Redundancy analysis shows that soil pH, TN, SOC and EC were the major driving factors of soil microbial activity. Our results indicate that strong allelopathic impact of root extracts on plant growth and soil microbial activity by mimicking roots exudate, providing novel insights into the role of plant–soil microbe interactions in mediating invasion success.

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Relation between soil microbial activity and the effect of seed inoculation with the rhizopseudomonad strain 7NSK2 on plant growth

Biology and Fertility of Soils ◽

10.1007/bf00255775 ◽

1987 ◽

Vol 3 (3) ◽

pp. 147-151 ◽

Cited By ~ 20

Author(s):

A. Iswandi ◽

P. Bossier ◽

J. Vandenabeele ◽

W. Verstraete

Keyword(s):

Plant Growth ◽

Microbial Activity ◽

Soil Microbial Activity ◽

Soil Microbial ◽

Seed Inoculation

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The Chemical Composition of Biogas Digestates Determines Their Effect on Soil Microbial Activity

Agriculture ◽

10.3390/agriculture10060244 ◽

2020 ◽

Vol 10 (6) ◽

pp. 244 ◽

Cited By ~ 2

Author(s):

Kerstin Nielsen ◽

Christina-Luise Roß ◽

Marieke Hoffmann ◽

Andreas Muskolus ◽

Frank Ellmer ◽

...

Keyword(s):

Soil Respiration ◽

Microbial Activity ◽

Laboratory Experiments ◽

Lignin Content ◽

Control Level ◽

Carbon Mineralization ◽

Soil Microbial Activity ◽

Short Term ◽

Soil Microbial ◽

Different Soils

Digestates are commonly used as organic inputs in agriculture. This study aimed to answer four questions: (1) What are the immediate and longer-term impacts of digestates on soil microbial activity?; (2) How much of the digestates’ carbon is mineralized within the first months? (3) How do the nitrogen, lignin, cellulose, and hemicellulose contents of digestates influence microbial activity and carbon mineralization? (4) How does the soil type influence mineralization? To investigate this, dehydrogenase activity (DHA) was measured in a field trial and in laboratory experiments with five digestates (DGs), cattle slurry, and cattle manure. DHA measurements were supplemented with soil respiration experiments using two different soils. DHA was significantly increased by all organic inputs, but decreased back to the control level within seven months under field conditions. Twenty percent to 44% of the organic carbon (Corg) in the digestates was converted to CO2 after 178 days. Soil respiration was significantly negatively correlated to lignin content (r = −0.82, p < 0.01) and not correlated to nitrogen, cellulose, or hemicellulose content. On the basis of equal carbon application, slurry promoted soil respiration and DHA more strongly than digestates in the short term.

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