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Determining the effect of perennial energy crop (PEC) cultivation on soil organic carbon (SOC) in marginal land soil is vital for carbon neutrality and bioeconomy development. However, a comprehensive and systematic evaluation of the response of SOC content to different PECs and its underlying drivers is still lacking. We used soil data collected from infertile red topsoil (0–20 cm) after 10 years of cultivation with Miscanthus (MS), Panicum virgatum (SG), and Saccharum arundinaceum (SA) to explore the changes in SOC stock induced by PEC. The roles of physical, chemical, and microbiological factors driving the increase in the SOC stock were investigated. Results revealed that SA and MS enhanced SOC stock by 87.97% and 27.52% relative to the uncultivated control. Conversely, PEC increased the percentage of soil mega‐aggregates, geometric mean diameters, soil chelate iron (Fe), and aluminum (Al) oxides, and reduced soil acidity for the infertile red soils. In addition, fungal richness and diversity for PEC soils were enhanced compared to the unplanted soil. It is possible that PEC cultivation reduced the relative abundance of copiotrophic fungi but increased the relative abundance of oligotrophic fungi. Furthermore, variance partitioning analysis revealed that chemical and microbiological factors accounted for 80.54% of the total variation for the SOC stock. The partial least squares path model showed that PEC cultivation enhanced soil carbon (C) stock via soil deacidification and increased soil bacterial function. In conclusion, this study confirms the SOC sequestration potential of PEC cultivation in marginal land and the underlying mechanism driving SOC stock. The main positive factors controlling soil C sequestration included "pH," while the negative factors were "bacterial community," "fungal community," and "bacterial function." Our research may help encourage and support decision‐makers of wasted marginal land conversion to PEC cultivation. [ABSTRACT FROM AUTHOR]

Potential impacts of climate change on grain sorghum ( Sorghum bicolor) productivity were investigated using the CERES-sorghum model in the Decision Support System for Agrotechnology Transfer v4.5. The model was first calibrated for a sorghum cultivar grown in a free air CO2 enrichment experiment at the University of Arizona, Maricopa, Arizona, USA in 1998. The model was then validated with an independent dataset collected in 1999. The simulated grain yield, growth, and soil water of sorghum for the both years were in statistical agreement with the corresponding measurements, respectively. Neither simulated nor measured yields responded to elevated CO2, but both were sensitive to water supply. The validated model was then applied to simulate possible effects of climate change on sorghum grain yield and water use efficiency in western North America for the years 2080-2100. The projected CO2 fertilizer effect on grain yield was dominated by the adverse effect of projected temperature increases. Therefore, temperature appears to be a dominant driver of the global climate change influencing future sorghum productivity. These results suggest that an increase in water demand for sorghum production should be anticipated in a future high-CO2 world. [ABSTRACT FROM AUTHOR]

Organic waste is an important biomass resource. In this study the definition of coefficients for the calculation of all the secondary 10 forestry residue categories was improved and established according to literature reviewing of previous reports between 1982 and 2017. The rationality of value-taking for each coefficient in previous literature was examined by tracing to its citation sources. The irrational, or unstudied coefficients were assessed using the data in previous reports or questionnaire surveys. Lastly, values of the coefficient for the calculation of woody nursery residue, forest woody pruning residue, wood logging residue, firewood, wood bucking residue, wood handling residue, waste wood, banana and pineapple plant residue, bamboo processing residue and waste bamboo were reasonably assessed in this study.

In this study, models for assessing resources of forestry residues were improved based on analysis of previous studies and current forest production in China. And novelties are highlighted: this study covered the models for the calculation of 10 secondary forestry residues from woody nursery, forest woody pruning, wood logging, firewood, wood bucking, wood handling, waste wood, banana and pineapple plants, bamboo processing and waste bamboo; the residues produced from fast-growing forest for logging and processing of imported wood were taken into consideration to calculate woody residue potential; the calculation of pruning residue included woody fruit trees, and herbaceous fruit plants from the management of orchard and other economic forest; the consistency of parameter terminology and definition which referred from their literature resources have been ensured; more studies focused on the coefficient values, industrial standard, forestry residue amount and spatial distribution are recommended for future researches.