Five facts you didn’t know about c4-grass

Have you ever wondered why Jord uses C4-grass to remove carbon from the atmosphere and as feedstocks to produce solid biofuels and biochar?

Have you ever wondered why Jord uses C4-grass to remove carbon from the atmosphere, regenerate the soil, and produce solid biofuels and biochar?

As the world strives to reduce carbon emissions and combat climate change, C4-grasses have emerged as a promising solution. These grasses boast high water and nutrient use efficiency and productivity, making them ideal for adapting to rapidly changing climate conditions. Additionally, they serve as an excellent source of quality fodder, which is crucial as demand for agricultural products rises with increasing living standards and meat consumption. Over the past decade, efforts to reduce reliance on fossil fuels and lower energy costs have driven a surge in biofuel production, primarily from grain. C4-grass presents an excellent alternative to meet this growing demand.

The utilization of agriculturally degraded and marginal lands for carbon capture and storage has also been explored. Research indicates that restoring high plant diversity, particularly late-successional grassland plant diversity that includes C4-grasses and legumes, significantly enhances carbon capture and storage rates on degraded and marginal agricultural lands. With their remarkable carbon-capturing ability, C4-grasses offer a unique and natural solution in the fight against climate change.

C4-grasses are truly remarkable. During photosynthesis, these perennial grasses utilize a specific metabolic process called the C4-pathway (Hatch–Slack pathway). This pathway is more efficient than the alternative C3 pathway used by most plants, particularly under hot and dry conditions. Examples of C4-grasses include corn, sugarcane, napier grass, and several species of sorghum, switchgrass, and millet. These plants are commonly used for food and animal feed, biofuel generation, and ornamental purposes. Here are some key facts about these grasses that you may not know.

1.C4-grass is well adapted to hot and dry conditions

C4-grasses are considered more heat and water-stress tolerant than C3 species (Sage & Monson, 1999). This is because C4 pathways have an evolutionary advantage for adaptation to hot and dry climates (Guralnick et al. 2008) and are efficient in water conservation. This ability has led to expanding the C4 grassland biome in warm climates (Edwards et al., 2010). Hence, such grasslands exhibit high productivity, and high light and temperature adaptability.

2. C4-grass shows efficient water and nutrient use and high drought resilience

Certain C4-grass can thrive without irrigation with only sporadic rains during the growing stage in areas with limited water supply. This is possible because some C4-grasses are well suited to hot and dry environments and have developed a drought stress response mechanism. Some examples include slow growth, closing stomata, increasing leaf rolling/erectness by osmotic adjustment, accumulating compatible solutes, and decreasing transpiration. Its root systems can even reach depths of 200 cm, enabling efficient water and nutrient resource capture while boosting soil carbon deposition. Furthermore, high-biomass C4-grasses such as Napier grass, Miscanthus, Sugarcane, and Sorghum utilize nitrogen more efficiently than grain crops due to effective nitrogen recycling inside the canopy during vegetative growth. (Mullet, 2017).

3. C4-grass efficiently sequester CO₂

Degraded and marginal lands, unsuitable for food crop cultivation due to low fertility or high environmental stress, can remove atmospheric CO₂ and sequester it as soil organic matter during natural succession. However, this process is slow, requiring centuries to re attain pre agricultural soil carbon levels (Yang et al., 2019). Utilizing marginal land for perennial C4-grass can provide biomass feedstocks and serve as a potential strategy for climate change mitigation. These perennial grass can help mitigate rising CO₂ levels thanks to their positive response to increased CO₂ (Faria et al., 2018) and their capacity to naturally sequester atmospheric CO₂. Schemes that set aside agricultural lands to grow C4-grass have demonstrated a rapid rise in labile soil carbon and total long-term carbon sequestration over the years (Piñeiro et al., 2009). Researchers revealed that long term perennial energy crop cultivation increases soil carbon stocks despite the complete removal of aboveground biomass (Xu et al., 2022).

4. C4-grasses exhibit high biomass yield. Ideal as feedstock for biofuel production

C4 types of grass exhibit high biomass results thanks to C4 photosynthesis, efficient capture and use of light, long growth duration pattern and water and nutrients used. Certain high biomass C4-grass stems can accumulate high levels of nonstructural carbohydrates, which could be modified to increase biomass yield and utility as biofuel feedstocks (Mullet, 2017). Additionally, perennial C4-grasses benefit from soil microbial associations, reducing nutrient needs. Grasses with low moisture content, high lignin and low nutrients are desired for combustion since they provide better efficiency and quality in biofuel conversion (Tubeileh, Rennie & Goss, 2016). For warmer areas, some studies have identified Napier grass among the most promising candidates for biofuel production, becoming an efficient strategy to use marginal farmlands in most temperate and tropical climates; it has an excellent energy balance; the feedstocks can be used conveniently in a variety of energy applications; and it is environmentally friendly. Densified warm season grass is poised to become a significant global fuel source because it can meet some heating requirements at less cost than all other alternatives available today (Samson et al., 2005).

5. C4-grass has the potential to restore degraded and marginal land

C4-grasses are known for their ability to establish deep root systems and build organic matter in soils. Planting these grasses on degraded land can restore the soil in several ways.

• Increase soil organic matter: C4-grasses have deep root systems penetrating compacted soils and bringing nutrients from deeper layers. As they grow, they add organic matter to the soil, improving soil structure and water-holding capacity.

• Enhance soil microbial activity: C4-grasses also increase the microbial activity in the soil by providing a source of carbon and nutrients. This leads to an increase in soil biodiversity and can improve nutrient cycling.

• Increase soil carbon sequestration: Marginal land covered by perennial C4-grass reduces soil diurnal temperature ranges. It also provides organic plant residues, which stimulate microbial activity, transforming residues into particulate organic matter, microbial biomass, soil organic carbon, and increased soil carbon sequestration. Labile soil carbon pools (particulate organic matter and microbial biomass) greatly influence carbon sequestration rates in semi-arid coarse soils. (Li et al., 2017).

In summary, planting C4-grasses on degraded land can help restore soil health and productivity while offering other benefits such as increased biodiversity and carbon sequestration. However, the success of this restoration strategy depends on various factors, including the specific grass species used, site conditions, and management practices such as fertilization and pest control.

Reference

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