Plant Biomass Carbon Research Articles

Old-growth Ficus trees provide soil water and carbon storage to urban greenspaces in a Brazilian metropolis

Urban flooding has been considered one of the most severe natural disasters around the world, and urban greenspaces can provide important flood regulation ecosystem services. In Belo Horizonte (Brazil), the woody vegetation, especially the old-growth Ficus trees, appears to protect an urban park against the flooding of the Arrudas river. Thus, we compared the soil water content, soil water-holding capacity, soil aggregation and porosity among a highly permeable urban park planted with herbaceous and woody species, including Ficus, a semi-permeable parking lot with only Ficus and an impermeable site without trees (Disturbed Site-DS). The soil water content and water holding capacity of the urban park did not differ from that of the Ficus site, but it was lower than DS. These results were correlated with soil organic matter (SOM) content, soil aggregation and porosity, suggesting that Ficus trees play an important role in the hydrological cycle. To understand how the Fiscus species provide such soil permeability, we compared the aboveground plant biomass, soil fertility and soil carbon sequestration (total soil carbon, soil organic matter, humic and fulvic acids and soil isotopic δ13 C) in plots with Ficus and without this species within the park as well as in a preserved urban forest and a disturbed square. The outstanding plant biomass produced by Ficus species explained the high soil carbon sequestration, particularly in humic organic matter, favouring soil aggregation, porosity and water retention. Therefore, Ficus species may be considered an exceptional C-sequestering species, contributing for soil stabilization and the hydrological cycle in urban greenspaces.

Effects of Thinning on Carbon Storage in a Mixed Broadleaved Plantation in a Subtropical Area of China

Forest thinning is a widely used silvicultural method in forest management and has complex effects on carbon sequestration in different types of forest ecosystems. The present study examined the short-term effects of different thinning intensities on carbon storage in an 11-year-old mixed broadleaved plantation. The results partially supported that different thinning intensities have varying impacts on carbon storage in different parts of forest ecosystems. The main results were as follows: (1) The effect of thinning on promoting the growth of fast-growing tree species (Michelia macclurei Dandy and Schima superba Gardn. et Champ.) was earlier than that of slow-growing tree species (Castanopsis hystrix Miq.). (2) A greater thinning intensity conferred greater effects on promoting the tree biomass carbon growth, litter carbon storage, and understory plant diversity, in the order of 41%~50% > 31%~40% > 20%~30%, but these values were lower than those for the unthinned plots. (3) The soil carbon storage declined most in the 41%~50% thinned plots, due to the reduced carbon storage in the humus layer. (4) The 20%~30% thinning intensity promoted carbon sequestration in the short term in the mixed broadleaved plantation. The results suggested that a lower thinning intensity promoted carbon sequestration in the short term, a greater thinning intensity reduced carbon storage at first, but the negative effect on carbon storage exhibited trade-offs later by the growth of tree and understory plant biomass carbon and the accumulation of litter layer carbon.

Transformation scenarios towards multifunctional landscapes: A multi-criteria land-use allocation model applied to Jambi Province, Indonesia

In tropical regions, shifting from forests and traditional agroforestry to intensive plantations generates conflicts between human welfare (farmers’ demands and societal needs) and environmental protection. Achieving sustainability in this transformation will inevitably involve trade-offs between multiple ecological and socioeconomic functions. To address these trade-offs, our study used a new methodological approach allowing the identification of transformation scenarios, including theoretical landscape compositions that satisfy multiple ecological functions (i.e., structural complexity, microclimatic conditions, organic carbon in plant biomass, soil organic carbon and nutrient leaching losses), and farmers needs (i.e., labor and input requirements, total income to land, and return to land and labor) while accounting for the uncertain provision of these functions and having an actual potential for adoption by farmers. We combined a robust, multi-objective optimization approach with an iterative search algorithm allowing the identification of ecological and socioeconomic functions that best explain current land-use decisions. The model then optimized the theoretical land-use composition that satisfied multiple ecological and socioeconomic functions. Between these ends, we simulated transformation scenarios reflecting the transition from current land-use composition towards a normative multifunctional optimum. These transformation scenarios involve increasing the number of optimized socioeconomic or ecological functions, leading to higher functional richness (i.e., number of functions). We applied this method to smallholder farms in the Jambi Province, Indonesia, where traditional rubber agroforestry, rubber plantations, and oil palm plantations are the main land-use systems. Given the currently practiced land-use systems, our study revealed short-term returns to land as the principal factor in explaining current land-use decisions. Fostering an alternative composition that satisfies additional socioeconomic functions would require minor changes (“low-hanging fruits”). However, satisfying even a single ecological indicator (e.g., reduction of nutrient leaching losses) would demand substantial changes in the current land-use composition (“moonshot”). This would inevitably lead to a profit decline, underscoring the need for incentives if the societal goal is to establish multifunctional agricultural landscapes. With many oil palm plantations nearing the end of their production cycles in the Jambi province, there is a unique window of opportunity to transform agricultural landscapes.

Plant root mechanisms and their effects on carbon and nutrient accumulation in desert ecosystems under changes in land use and climate.

Deserts represent key carbon reservoirs, yet as these systems are threatened this has implications for biodiversity and climate change. This review focuses on how these changes affect desert ecosystems, particularly plant root systems and their impact on carbon and mineral nutrient stocks. Desert plants have diverse root architectures shaped by water acquisition strategies, affecting plant biomass and overall carbon and nutrient stocks. Climate change can disrupt desert plant communities, with droughts impacting both shallow and deep-rooted plants as groundwater levels fluctuate. Vegetation management practices, like grazing, significantly influence plant communities, soil composition, root microorganisms, biomass, and nutrient stocks. Shallow-rooted plants are particularly susceptible to climate change and human interference. To safeguard desert ecosystems, understanding root architecture and deep soil layers is crucial. Implementing strategic management practices such as reducing grazing pressure, maintaining moderate harvesting levels, and adopting moderate fertilization can help preserve plant-soil systems. Employing socio-ecological approaches for community restoration enhances carbon and nutrient retention, limits desert expansion, and reduces CO2 emissions. This review underscores the importance of investigating belowground plant processes and their role in shaping desert landscapes, emphasizing the urgent need for a comprehensive understanding of desert ecosystems.

Consequences of plateau pika disturbance on plant-soil carbon and nitrogen in alpine meadows.

The presence of burrowing mammals can have extensive effects on plants and soils, creating bare soil patches in alpine meadows and potentially altering plant-soil carbon (C) and nitrogen (N). This study focuses on the plateau pika (Ochotona curzoniae) to examine the responses of plant-soil C and N to a small burrowing mammal from quadrat scale to plot scale. The density of active burrow entrances in disturbed plots was used as an indicator of the disturbance intensity of plateau pikas. The study found that the below-ground biomass (BGB) and its C and N, as well as soil C and N concentrations were significantly lower in bare soil areas than in vegetated areas and undisturbed plots. This shows that the quadrat scale limited the estimation of the C and N sequestration potential. Therefore, further research on the plot scale found that the disturbance by plateau pika significantly reduced plant biomass and BGB carbon stock. However, plateau pika did not affect soil C and N stocks or ecosystem C and N stocks. These findings suggest the bare soil patches formed by plateau pika caused plant and soil heterogeneity but had a trade-off effect on plant-soil C and N stocks at the plot scale. Nevertheless, moderate disturbance intensity increased the C and N sequestration potential in grassland ecosystems. These results provide a possible way to estimate how disturbance by small burrowing mammals affects C and N cycling in grassland ecosystems while accurately assessing the effects of small burrowing mammal densities on C and N in grassland ecosystems.

Temperature response of soil respiration decreases with latitude and elevation in abandoned croplands

Soil respiration (Rs), a critical component of the global carbon cycle, is highly sensitive to warming. Agricultural soils, including abandoned croplands, are large sources of carbon dioxide to the atmosphere. However, the responses of Rs and its components to warming from abandoned croplands with no further management activities remain elusive at the national scale. Here, we report the warming responses of Rs, heterotrophic respiration (Rh), and autotrophic respiration (Ra) from China’s abandoned croplands spanning a large range in latitude (22.33–46.58°N) and elevation (2–3734 m) from three-year in situ warming experiments. We found that warming treatment (+1.6 °C) significantly stimulated Rs, Rh, and Ra by 30.4%, 37.2%, and 37.3%, respectively. The response of Rs to warming was higher in abandoned croplands (19.1% °C−1) than in other terrestrial ecosystems (5.4%–9.2% °C−1), attributing to greater increases in plant biomass and soil organic carbon induced by warming. Rs was more responsive to warming in low latitude or elevation regions with high plant biomass. Under the warming conditions, the apparent temperature sensitivity (Q10) of Rs increased in low latitude and elevation regions due to a decrease in soil carbon availability but decreased in high latitude and elevation regions due to an increase in carbon availability induced by warming. Despite the positive warming response of Rs, the net ecosystem productivity in abandoned croplands slightly increased by 18.7% attributing to increased plant productivity under warming. These findings demonstrate that Rs in abandoned croplands was more sensitive to warming in warmer regions than in colder regions, underscoring the importance of latitude- or elevation-induced variations in soil carbon availability in determining the response of Rs to warming and projecting cropland carbon-climate feedback.

Climate Change Will Increase Biomass Proportion of Global Forest Carbon Stocks Under an SSP5–8.5 Climate Trajectory

AbstractA large amount of carbon is stored in global forests. However, the fraction of carbon stored as plant biomass versus soil organic carbon (SOC) varies among forest types, and potential changes over the 21st century are uncertain. Here, we used extensive data derived from inventories and remote sensing and Coupled Model Intercomparison Project Phase 6 (CMIP6) models to examine the current and 21st century dynamics in the proportion of biomass and SOC across global forests. We found that precipitation, elevation, soil, and wildfire were the primary controls of these differences in carbon pools. Under the SSP5–8.5 climate scenario, CMIP6 models project that the ratio of biomass to ecosystem carbon in global forests will increase across the 21st century, with the largest increases in boreal forests (95 ± 37%) compared to moist tropical forests (16 ± 15%). Changes in forest carbon pools resulting in greater biomass fraction will affect disturbance, and ecosystem carbon and energy balances, all of which interact with the climate system.

A Comprehensive Review on Biochar

Biochar from the pyrolysis of organic biomass is a highly porous carbon with many useful applications. While providing practical options for disposal and disease control, it also contributes to carbon sequestration by trapping carbon in plant biomass. The composition and structure of biochar depends on factors such as temperature, heating rate and production time. It also leads to bio-oil and biogas, which can be used for biochar production, electricity generation and the production of various chemicals. Incorporating biochar into the soil improves pH, electrical conductivity, water holding capacity, cation exchange capacity and microbial activity.It reduces nutrient leakage and all necessary fertilizers reduce environmental pollution. Biochar also plays an important role in crop improvement. Besides improving the soil, biochar also has the advantage of reducing greenhouse gas emissions, reducing pesticide use and being used in the construction, cosmetics and treatment, wastewater and food industries. India is rich in biomass resources and has great potential for biochar production. This study explores various production technologies, their effects on biochar energy and the benefits of using biochar.

Subtle Responses of Soil Bacterial Communities to Corn-Soybean-Wheat Rotation

Crop rotational diversity can improve crop productivity and soil health, and boost soil microbial diversity. This research hypothesized that a 3-year rotation of corn-soybean-wheat (CSW), compared with a 2-year corn-soybean (CS) rotation, would result in a more diverse and more complex soil bacterial community, together with a greater abundance of beneficial bacteria. This was evaluated in a replicated experiment established in 2013 at two locations in Ohio (United States). The soil bacterial communities under soybean were compared between CS and CSW at both studied sites in 2018 and 2019, through 16S ribosomal DNA amplicon metabarcoding. Experimental site was the main driver of bacterial richness and evenness. Significant effects on bacterial community composition were observed in response to the interaction between site, rotational sequence, and year of study. Eight bacterial amplicon sequence variants were identified within all CSW treatments and were not present in CS. Several taxa were differentially abundant between rotation treatments, including the genera Ralstonia being more abundant in CS. Co-occurrence networks, including hub taxa, were generally different between rotation treatments and year, with more structure observed in CSW networks for one of the studied sites. Few bacterial genera were consistently identified as hubs across all networks, including an unidentified member of order Acidobacteriales, while other hubs were unique for CSW networks, including members of the family Gemmatimonadaceae. Finally, the composition of the bacterial communities at the northwestern site positively correlated with plant biomass and active carbon, whereas more recalcitrant pools (total carbon and organic water) correlated with the bacterial communities at the western site.

Microbial carbohydrate-active enzymes influence soil carbon by regulating the of plant- and fungal-derived biomass decomposition in plateau peat wetlands under differing water conditions.

Peatlands are important carbon sinks and water sources in terrestrial ecosystems. It is important to explore their microbial-driven water-carbon synergistic mechanisms to understand the driving mechanisms of carbon processes in peatlands. Based on macrogenomic sequencing techniques, located on the peatland of the eastern margin of the Tibetan Plateau with similar stand and different water conditions, we taken soil properties, microbiome abundance, CAZyme abundance and enzyme gene pathways as the object of study, investigated the characterization of soil microbial carbohydrate-active enzymes (CAZymes) under different water gradients in peatland. According to the results, these three phyla (Chloroflexi, Gemmatimonadetes, and Verrucomicrobia) differed significantly between water gradients. Under dried wetlands, the abundance of CAZymes involved in hemicellulose and glucan degradation increased by 3.0 × 10-5 and 3.0 × 10-6, respectively. In contrast, the abundance of CAZymes involved in chitin degradation decreased by 1.1 × 10-5 (p < 0.05). It highlights that regulating plant- and fungus-derived carbon metabolism processes by soil microorganisms in highland peatlands is a crucial mechanism for their response to water changes. Most plant-derived carbon fractions are regulated by soil enzymes (endo-beta 1,4-xylanase, alpha-L-arabinofuranosidase, and alpha-L-fucosidase) containing CAZymes functional genes. Additional findings in this enzyme gene pathway indicate that water changes that affect soil carbon fractions indirectly influence the three enzyme gene metabolic pathways related to plant carbon sources (the glycolysis/gluconeogenesis, other glycan degradation and amino sugar, and nucleotide sugar metabolism). Overall, this study highlights the significance of microbial CAZymes in highland peatland soil carbon processes and indicates that microbial conversion of plant and fungal biomass carbon is more sensitive to water changes.

Allometry and Aboveground Biomass of Acacia auriculiformis A. Cunn.ex Benth Based Agroforestry Systems in Yangambi Landscape, Democratic Republic of Congo

Most of the population living near the Yangambi Biosphere Reserve lives mainly from slash-and-burn agriculture which causes deforestation. The agroforestry system (AFS) is reputed to stabilise agriculture, store carbon in plant biomass and in the soil, and improve soil fertility. Acacia auriculiformis is a fast-growing leguminous tree that has been planted in AFS in the Yangambi landscape, but few or no studies assessed its aboveground biomass storage. This study aims to determine the aboveground biomass storage of AFS-based Acacia auriculiformis when intercropped with cassava, maise, and peanut food crops at different tree planting densities in the Yangambi landscape. The experimental device is a multifactorial trial of 36 plots of 400 m2 each one; with 4 treatments and 3 repetitions for each of these tree species in association with maise, groundnut, and cassava. Therefore, for assessing the aboveground biomass, the stem circumference and tree height were taken in each plot. Moreover, to study the A. auriculiformis allometry, 30 trees were cut and the aboveground biomass was estimated from the local allometric model set up in this study. Through this work, we have developed the three best allometric models for estimating the aboveground biomass of A. auriculiformis. The result showed that the aboveground biomass of A. auriculiformis varies between 0.49 and 10.54 t/ha (0.25 to 5.27 t/ha of carbon) depending on tree planting density and food crops. By comparing the results of the current study with those of others who worked on A. auriculiformis biomass, it was noted that the local models developed in this study contribute to increasing the precision of carbon estimation in the Congo basin. This is important for the implementation of REDD+ projects (Reducing emissions from deforestation and forest degradation) in the DRC. In conclusion, agroforestry plantations contribute to storing carbon in plant biomass.

Long-Term Grazing Exclusion Increases Ecosystem Carbon Stock but Decreases Nitrogen Stock in the Karst Alpine Grassland of China

Grazing management practices are a major factor regulating nutrient cycling and plant growth in grasslands. However, the response of long-term grazing regimes to ecosystem carbon and nitrogen accumulation and plant productivity remains uncertain in karst landscapes. The purpose of this research is to assess the effects of long-term management measures on plant biomass and ecosystem organic carbon (EOCS), total nitrogen (ETNS), and phosphorus (ETPS) stocks in a karst alpine grassland. A 17 year-long field experiment, constituting the methods of grazing exclusion (GE), continuous grazing (CG), mowing and grazing (MG), and rotational grazing (RG) was established in 2001. Plant and soil samples were collected in 2017. Grazing treatments significantly reduced the aboveground and root biomass (MG and RG) compared to GE. SOC of GE was higher than that of CG, MG, and RG in each soil layer. Grazing promoted the mean TN content with a significant increase in CG and RG. GE significantly increased the EOCS and decreased the ETNS and ETPS. The EOCS increased by 22.29% (MG) and 16.31% (RG) and ETNS increased by 7.76% (RG), and MG significantly decreased ETNS compared to CG. EOCS were positively related to SOC, stoichiometry, and aboveground biomass, while being negatively correlated with TP; ETNS were positively related to TN and TP, while being negatively correlated with C/N, C/P, aboveground biomass, and root biomass; ETPS were positively correlated with TN and TP and negatively correlated with NH4+-N and stoichiometry. GE can provide significant improvements in plant recovery and ecosystem carbon stock, whereas RG is beneficial for promoting ecosystem nutrient stock under the condition of pasturing utilisation in the karst grasslands.

Redesigning Carbon-Carbon Backbone Polymers for Biodegradability-Compostability at the End-of-Life Stage.

Carbon-carbon backbone polymers are non-biodegradable, persistent plastics that have accumulated on land and oceans due to human activities. They degrade and fragment into microplastics and smaller particle sizes but do not biodegrade at an acceptable and practical rate. Their continual buildup in the natural environment precipitates serious detrimental impacts on human health and the environment, as extensively documented in the literature and media. Nearly 77% of global plastics produced are carbon-carbon backbone polymers. More importantly, 90% of packaging plastics (153.8 million metric tons) are non-biodegradable, persistent carbon-carbon backbone polymers. The recycling rate of these non-durable packaging plastics ranges from 0 to 4%. Re-designing carbon-carbon backbone polymers to labile ester backbone biodegradable-compostable polymers and treating them along with biodegradable organic waste (such as food, paper, and organic wastes) in managed industrial composting is environmentally responsible. Diverting 1 million metric tons of biodegradable organic wastes in MSW bound for landfills and open dumps to industrial composting results in 0.95 million metric tons CO2 equivalents of GHG emissions reduction. This perspective paper discusses strategies and rationales regarding the redesign of carbon-carbon backbone polymer molecules. It describes the carbon footprint reductions achievable by replacing petro-fossil carbon with plant biomass carbon. Biodegradability and compostability are frequently used but misunderstood and misused terms, leading to misleading claims in the marketplace. This paper presents the fundamentals of biodegradability and compostability of plastics and the requirements to be met according to ASTM/ISO international standards.

THE INFLUENCE OF GENOTYPE, SOIL TILLAGE AND FERTILISATION ON CARBON SEQUESTRATION IN MAIZE

The increase in the concentration of greenhouse gases in the Earth’s atmosphere, especially that of CO2, is a major concern because it is the main source leading to global warming, and its impact on climate change is still widely studied. The intensity and frequency of drought and flooding increase due to the change in climate, which has a negative impact on crop productivity and food security. The aim of this paper was to demonstrate the role of corn in carbon sequestration based on plant biomass and soil organic carbon accumulation. We presented the main factors that contribute to carbon sequestration and concrete examples regarding the capacity of corn hybrids created at National Agricultural Research and Development Institute (NARDI) Fundulea, as well as aspects regarding the importance of soil tillage and fertilisation. In contrast to genotypes in which this ratio was lower, maize genotypes that demonstrated a rise in the root:stem ratio under drought stress conditions produced more biomass, suggesting that the roots of these genotypes can grow at water potentials where stem growth is inhibited, which are attributes that also prove their good potential for carbon sequestration under climate change conditions. The organic carbon content in the superficial soil layer decreased with the intensification of the degree of soil mobilisation (9.95% when working the soil with the chisel, 17.91% for ploughing), but fertilisation had a beneficial effect. The biomass was higher than that of the unfertilised soil. This means that a higher carbon input has a positive influence on the carbon stock in the soil.

Shifts in Above‐ Versus Below‐Ground Carbon Gains to Terrestrial Ecosystems Carbon Sinks Under Excess Nitrogen Inputs

AbstractAlthough elevated atmospheric nitrogen (N) deposition can increase terrestrial carbon (C) sinks, the persistence of this C acquisition depends partly on the responses of plant biomass and soil organic carbon (SOC) to long‐term exogenous N input. Experiments with N‐additions show increases in above‐ground biomass (AGB), although C dynamics between above‐ and below‐ground under N enrichment are unconnected in many studies. Here, we meta‐analyzed data from 362 N‐addition experiments globally and found that both AGB (+34%) and below‐ground biomass (BGB, +13%) positively but root‐to‐shoot ratios negatively (−15%) responded to N addition. These responses were reversed, however, when the experimental duration was over 20 years, wherein BGB increased and AGB was unchanged or even declined, during which time plants invested more C into roots. The effects of increased AGB were weak and negative, whereas those of increased BGB were robust and positive on SOC. Under chronic N deposition, the significant increase in SOC (5%) was associated with the increased root C inputs and decreased soil C losses rather than with increased above‐ground C inputs. The results suggest that the sequestration of below‐ground C exceeds that of above‐ground C to sustain terrestrial C gain during long‐term N deposition.

Soil microbial and macroinvertebrate functional diversity in response to Zokor disturbance in Tibetan alpine meadow

Soils contain a remarkable diversity of organisms that are important regulators of ecosystem functions. However, the knowledge of how the environment shapes biodiversity patterns below ground remains limited in alpine areas of the Tibetan Plateau. Here, we conducted a microhabitat scale study (400 m2 plot) integrating data on soil and plant community characteristics to explore the driving forces of functional diversity of soil microbial and macroinvertebrate communities under disturbance by plateau zokor (Eospalax baileyi), a subterranean rodent inhabiting the Tibetan Plateau. The results show that plateau zokor disturbance led to a decline in the belowground biomass of grasses, whereupon the total belowground plant biomass and soil organic carbon decreased significantly. The functional diversity of soil microbial and macroinvertebrate communities was significantly increased under plateau zokor disturbance. Redundancy analysis indicated that soil moisture, temperature and compaction, in combination with plant species richness and belowground biomass of forb were the most important factors in driving soil microbial and macroinvertebrate functional diversity. Piecewise structural equation modeling (SEM) revealed that plateau zokor mound disturbance had positive effects on the functional diversity of soil microbial and macroinvertebrate communities by regulating soil physical properties (moisture, temperature, and compaction) and plant species richness within the habitat. Further, zokor disturbance affected the functional diversity of soil microbial and macroinvertebrate communities indirectly via regulating soil organic carbon. Our study provides evidence that the functional diversity of microbes is more driven by environmental changes than those of macroinvertebrates.

Atmospheric phosphorus deposition amplifies carbon sinks in simulations of a tropical forest in Central Africa.

Spatial redistribution of nutrients by atmospheric transport and deposition could theoretically act as a continental-scale mechanism which counteracts declines in soil fertility caused by nutrient lock-up in accumulating biomass in tropical forests in Central Africa. However, to what extent it affects carbon sinks in forests remains elusive. Here we use a terrestrial biosphere model to quantify the impact of changes in atmospheric nitrogen and phosphorus deposition on plant nutrition and biomass carbon sink at a typical lowland forest site in Central Africa. We find that the increase in nutrient deposition since the 1980s could have contributed to the carbon sink over the past four decades up to an extent which is similar to that from the combined effects of increasing atmospheric carbon dioxide and climate change. Furthermore, we find that the modelled carbon sink responds to changes in phosphorus deposition, but less so to nitrogen deposition. The pronounced response of ecosystem productivity to changes in nutrient deposition illustrates a potential mechanism that could control carbon sinks in Central Africa. Monitoring the quantity and quality of nutrient deposition is needed in this region, given the changes in nutrient deposition due to human land use.

Carbon Sequestration Potential in Coconut based Cropping System: A Review

Carbon sequestration plays a significant part in alleviating climate change by changing over climatic carbon as plant biomass and soil organic carbon. Since trees can hold greater carbon in their biomass than other plant types, perennial plantations have a vital function in mitigating the adversities in climate. Coconut is a perennial palm with a life time of around 50-60 years has the capability to store carbon for a long time, especially in the stem. Due to the increased availability of space and solar radiation reaching the understorey, the carbon sequestration capacity of coconut plantations can be considerably increased. As a result, intercropping or agroforestry in coconut lands is important not only for food and economic security but also for carbon sequestration. On an average carbon sequestration potential of coconut trees range between 37 kg tree-1 yr-1 (dwarf variety) up to 56 kg tree-1yr-1 (tall variety). After 20 years of establishment, monoculture coconut land can be transformed into perennial mixed cropping or agroforestry system that can sequester more carbon.

Removal of chemical oxygen demand, total phosphorus, and ammonia nitrogen from pickle wastewater by plant biomass carbon combined with a chemical oxidant

Removal of chemical oxygen demand, total phosphorus, and ammonia nitrogen from pickle wastewater by plant biomass carbon combined with a chemical oxidant

Study of the adsorption of methylene blue by phytoremediation-plant biomass carbon

Many kinds of plant biomass are used to prepare the plant biomass carbon (PBC) to treat printing and dyeing wastewater (PDW). However, few researchers have studied how effectively PBCs prepared from phytoremediatory plants after phytoremediation can treat the wastewater. Furthermore, whether new pollutants are introduced is an urgent issue that needs interrogation. Thus, the purposes of this study were (1) to gather data on the technical parameters, effects, and mechanism of methylene blue (MB) absorption by PBC prepared from Brassica juncea harvests containing Pb and Cd, and (2) to evaluate the environmental risks associated with the addition of Pb and Cd to PDW. PBC0 and PBC1 were both alkaline with a honeycomb porous structure and an uneven surface. The surface area of PBC1 was much larger than that of PBC0, and PBC1 had more micropores. The hydroxyl group (–OH) and the stretching vibration of CO could interact with MB molecules by hydrogen bonding and electrostatic attraction. In addition, PBCs attracted MB molecules through π-π bond formed by the aromatic CH bending, and the surface complexation would be formed by the interaction between MB molecules and Pb/Cd-O bond in the adsorption of MB by PBC1. The best technical parameters for B. juncea PBC were a PBC quality to wastewater volume ratio of 2.5 t/1000 m3, 50 mg/L; the mode of action and adsorption time set to oscillation for 6 h; a pH of 5; and single use of the PBC. Furthermore, there was no environmental risk during the preparation of PBC1 and in the adsorption process within the scale of this experiment.