How biochar works, and when it doesn't: A review of mechanisms controlling soil and plant responses to biochar

GCB Bioenergy, Journal Year: 2021, Volume and Issue: 13(11), P. 1731 - 1764

Published: July 27, 2021

Abstract We synthesized 20 years of research to explain the interrelated processes that determine soil and plant responses biochar. The properties biochar its effects within agricultural ecosystems largely depend on feedstock pyrolysis conditions. describe three stages reactions in soil: dissolution (1–3 weeks); reactive surface development (1–6 months); aging (beyond 6 months). As ages, it is incorporated into aggregates, protecting carbon promoting stabilization rhizodeposits microbial products. Biochar persists for hundreds thousands years. By increasing pH, porosity, water availability, biochars can create favorable conditions root functions. Biochars catalyze biotic abiotic reactions, particularly rhizosphere, increase nutrient supply uptake by plants, reduce phytotoxins, stimulate development, resilience disease environmental stressors. Meta‐analyses found that, average, P availability a factor 4.6; decrease tissue concentration heavy metals 17%–39%; build organic through negative priming 3.8% (range −21% +20%); non‐CO 2 greenhouse gas emissions from 12%–50%. show average crop yield increases 10%–42% with addition, greatest low‐nutrient P‐sorbing acidic soils (common tropics), sandy drylands due retention holding capacity. Studies report wide range diversity contexts which have been applied. Crop yields strongly if site‐specific constraints limitations are mitigated appropriate formulations. be tailored address site selection, modifying conditions, pre‐ or post‐production treatments, co‐application mineral fertilizers. demonstrate how, when used wisely, mitigates climate change supports food security circular economy.

Language: Английский

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Multifunctional applications of biochar beyond carbon storage

International Materials Reviews, Journal Year: 2021, Volume and Issue: 67(2), P. 150 - 200

Published: May 7, 2021

Biochar is produced as a charred material with high surface area and abundant functional groups by pyrolysis, which refers to the process of thermochemical decomposition organic at elevated temperatures in absence oxygen. The carbon component biochar relatively stable, and, hence, was originally proposed soil amendment store soil. has multifunctional values that include use it for following purposes: improve health, nutrient microbial carrier, immobilising agent remediation toxic metals contaminants water, catalyst industrial applications, porous mitigating greenhouse gas emissions odorous compounds, feed supplement animal health intake efficiency thus, productivity. This article provides first time an overview unintended consequences applications.

Language: Английский

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Positive but variable effects of crop diversification on biodiversity and ecosystem services

Global Change Biology, Journal Year: 2021, Volume and Issue: 27(19), P. 4697 - 4710

Published: June 11, 2021

Abstract Ecological theory suggests that biodiversity has a positive and stabilizing effect on the delivery of ecosystem services. Yet, impacts increasing diversity cultivated crop species or varieties in agroecosystems are still under scrutiny. The available empirical evidence is scattered scope, agronomic geographic contexts, services may depend type diversification strategy used. To robustly assess effects agroecosystems, we compiled results 95 meta‐analyses integrating 5156 experiments conducted over 84 experimental years representing more than 54,500 paired observations 120 85 countries. Overall, our synthesis data from across globe shows enhances not only production (median +14%) but also associated (+24%, i.e., non‐cultivated plants animals), several supporting regulating including water quality (+51%), pest disease control (+63%) soil (+11%). However, there was substantial variability for each individual service between different strategies such as agroforestry, intercropping, cover crops, rotation variety mixtures. Agroforestry particularly effective delivering multiple services, is, regulation quality, diseases regulation, biodiversity, long‐term productivity quality. Variety mixtures, instead, provide lowest benefits, whereas other show intermediate results. Our highlight while represents very promising sustainable land management, contributing to enhanced yields, some others key

Language: Английский

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Effects of manure fertilizer on crop yield and soil properties in China: A meta-analysis

CATENA, Journal Year: 2020, Volume and Issue: 193, P. 104617 - 104617

Published: April 27, 2020

Language: Английский

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Biochar in agriculture – A systematic review of 26 global meta‐analyses

GCB Bioenergy, Journal Year: 2021, Volume and Issue: 13(11), P. 1708 - 1730

Published: Sept. 1, 2021

Abstract Biochar is obtained by pyrolyzing biomass and is, definition, applied in a way that avoids its rapid oxidation to CO 2 . Its use agriculture includes animal feeding, manure treatment (e.g. as additive for bedding, composting, storage or anaerobic digestion), fertilizer component direct soil application. Because the feedstock carbon photosynthetically fixed from atmosphere, producing applying biochar essentially dioxide removal (CDR) technology, which has high‐technology readiness level. However, swift implementation of pyrogenic capture (PyCCS), needs deliver co‐benefits, example, improving crop yields ecosystem services and/or climate change resilience ameliorating key properties. Agronomic research rapidly evolving field moving less than 100 publications 2010 more 15,000 end 2020. Here, we summarize 26 rigorously selected meta‐analyses published since 2016 investigated multitude properties agronomic performance parameters impacted application, effects on yield, root biomass, water efficiency, microbial activity, organic greenhouse gas emissions. All show compelling evidence overall beneficial effect all parameters. One remaining challenges standardization basic analysis, still lacking many studies. Incomplete characterization increases uncertainty because adverse individual studies included might be related low‐quality biochars, would not qualify certification subsequent high content contaminants, salinity, incomplete pyrolysis, etc.). In summary, our systematic review suggests potential combine CDR with significant environmental co‐benefits.

Language: Английский

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Soil organic carbon response to global environmental change depends on its distribution between mineral-associated and particulate organic matter: A meta-analysis

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 793, P. 148569 - 148569

Published: June 22, 2021

Language: Английский

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Challenges of Smallholder Farming in Ethiopia and Opportunities by Adopting Climate-Smart Agriculture

Agriculture, Journal Year: 2021, Volume and Issue: 11(3), P. 192 - 192

Published: Feb. 26, 2021

Agriculture is the backbone of Ethiopian economy, and agricultural sector dominated by smallholder farming systems. The systems are facing constraints such as small land size, lack resources, increasing degradation soil quality that hamper sustainable crop production food security. effects climate change (e.g., frequent occurrence extreme weather events) exacerbate these problems. Applying appropriate technologies like climate-smart agriculture (CSA) can help to resolve This paper provides a comprehensive overview regarding opportunities challenges traditional newly developed CSA practices in Ethiopia, integrated fertility management, water harvesting, agroforestry. These commonly related drought resilience, stability yields, carbon sequestration, greenhouse gas mitigation, higher household income. However, adoption farmers often limited, mainly due shortage cropland, tenure issues, adequate knowledge about CSA, slow return on investments, insufficient policy implementation schemes. It suggested additional measures be made available become more prevalent should include utilization degraded marginal lands, improvement organic matter provision capacity-building financial support, well development specific policies for farming.

Language: Английский

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Global negative effects of nutrient enrichment on arbuscular mycorrhizal fungi, plant diversity and ecosystem multifunctionality

New Phytologist, Journal Year: 2020, Volume and Issue: 229(5), P. 2957 - 2969

Published: Nov. 14, 2020

Summary Despite widespread anthropogenic nutrient enrichment, it remains unclear how enrichment influences plant–arbuscular mycorrhizal fungi (AMF) symbiosis and ecosystem multifunctionality at the global scale. Here, we conducted a meta‐analysis to examine worldwide effects of on AMF plant diversity using data field experiments from 136 papers. Our analyses showed that addition simultaneously decreased abundance belowground aboveground The decreases in associated with were more pronounced increasing experimental duration, mean annual temperature (MAT) precipitation (MAP). Nutrient addition‐induced changes soil pH available phosphorus (P) predominantly regulated responses abundance. Furthermore, correlated under worldwide. findings identify negative suggest is closely linked function. This study offers an important advancement our understanding plant–AMF interactions their likely ongoing change.

Language: Английский

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An evaluation of carbon indicators of soil health in long-term agricultural experiments

Soil Biology and Biochemistry, Journal Year: 2022, Volume and Issue: 172, P. 108708 - 108708

Published: May 11, 2022

Soil organic carbon (SOC) is closely tied to soil health. However, additional biological indicators may also provide insight about C dynamics and microbial activity. We used SOC the other (potential mineralization, permanganate oxidizable C, water extractable β-glucosidase enzyme activity) from North American Project Evaluate Health Measurements examine continental-scale drivers of these indicators, relationships among effects health practices on indicator values. All had greater values at cooler temperatures, most were with increased precipitation clay content. The strongly correlated each site-level, strongest relationship between C. responded positively decreased tillage, inclusion cover crops, application nutrients, retention crop residue, but not number harvested crops in a rotation. effect tillage was generally sites higher precipitation. magnitude direction response consistent across within site measuring least two would confidence management, especially for tillage. an essential criterion evaluating Balancing cost, sensitivity, interpretability, availability commercial labs, 24-hr potential mineralization assay could deliver benefit measure conjunction SOC.

Language: Английский

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Greenhouse Gas Inventory Model for Biochar Additions to Soil

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(21), P. 14795 - 14805

Published: Oct. 12, 2021

Stabilizing the global climate within safe bounds will require greenhouse gas (GHG) emissions to reach net zero a few decades. Achieving this is expected removal of CO2 from atmosphere offset some hard-to-eliminate emissions. There is, therefore, clear need for GHG accounting protocols that quantify mitigation impact practices, such as biochar sequestration, have potential be deployed at scale. Here, we developed methodology application mineral soils using simple parameterizations and readily accessible activity data can applied range scales including farm, supply chain, national, or global. The method grounded in comprehensive analysis current empirical data, making it robust used many applications national inventories voluntary compliance carbon markets, among others. We show content varies with feedstock production conditions low 7% (gasification biosolids) 79% (pyrolysis wood above 600 °C). Of initial carbon, 63–82% remain unmineralized soil after 100 years mean annual cropland-temperature 14.9 °C. With method, researchers managers address long-term sequestration C through blended assessments life cycle analyses.

Language: Английский

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