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Summary: Stoichiometric rules may explain the allometric scaling among biological traits and body size, a fundamental law of nature. However, testing the scaling of elemental stoichiometry and growth to size over the course of plant ontogeny is challenging.Here, we used a fast‐growing bamboo species to examine how the concentrations and contents of carbon (C), nitrogen (N) and phosphorus (P), relative growth rate (G), and nutrient productivity scale with whole‐plant mass (M) at the culm elongation and maturation stages.The whole‐plant C content vs M and N content vs P content scaled isometrically, and the N or P content vs M scaled as a general 3/4 power function across both growth stages. The scaling exponents of G vs M and N (and P) productivity in newly grown mass vs M relationships across the whole growth stages decreased as a −1 power function.These findings reveal the previously undocumented generality of stoichiometric allometries over the course of plant ontogeny and provide new insights for understanding the origin of ubiquitous quarter‐power scaling laws in the biosphere. [ABSTRACT FROM AUTHOR]

Moso bamboo (Phyllostachys edulis), once highly praised worldwide, has been found to be a problematic species due to its unconstrained expansion into adjacent woodlands and negative effects on the function services of forest ecosystems. To determine the major factors affecting bamboo expansion into neighbor woodlands, we investigated the expansion characteristics of moso bamboo and the properties of stand structure and soil for 58 bamboo–woodland interfaces (BWIs) across Jiangxi province in China. Then, we analyzed the relationships between the variables of bamboo expansion and the properties of interfaces through a redundancy analysis. The characteristics (the expansion distance and the number and size of new culms) of moso bamboo expansion into disturbed forests were more significant (p < 0.01) than those into non-disturbed forests. The bamboo expansion into deciduous broad-leaved forest was much faster (1.33 m/yr) than evergreen broad-leaved forest (0.82 m/yr) and needle-leaved forest (1.08 m/yr). The characteristics of stand structure had more direct explanatory power (58.8%) than soil properties (4.3%) and their interaction (10.0%) for the variations in bamboo expansion. The canopy closure of recipient forests was identified as the most significant factor negatively correlated to bamboo expansion. The number of parent culms and the ratio of deciduous to evergreen trees ranked in sequence, and both imposed positive effects on the expansion. Regarding soil properties, only the water content was identified for its explanatory power and negative influence on bamboo expansion. Our findings illustrated that the expansion of moso bamboo showed remarkable variations when facing different woodlands. Stand characteristics (canopy closure, canopy height, etc.) of good explanatory power were the major variables affecting the expansion of moso bamboo. In order to control the expansion of bamboo and protect woodlands, disturbances (extracting timber, girdling trunks) should be prevented in bamboo–woodland interfaces. [ABSTRACT FROM AUTHOR]

Aims: Moso bamboo ( Phyllostachys pubescens) is a typical native invasive plant imposing serious threats on ecosystem processes and functions. A primary concern is alterations of litter and soil N mineralization in evergreen broadleaved forests coupled with bamboo population expansion. Methods: We conducted a field study to determine the litter production, quality, N resorption efficiency, and soil N mineralization rates in bamboo-dominated forest (BDF) and adjacent uninvaded evergreen broadleaved forest (EBF) in subtropical China. Results: The mean annual litter production for BDF was 5.82 Mg ha, 36.0 % lower than that for EBF (9.09 Mg ha). Litter N concentration was also lower, but C: N was higher after bamboo expansion, coupled with higher N resorption efficiency for Moso bamboo and lower litterfall, resulting in potential N return decreasing as much as 60.41 kg N ha yr to the soil. The soil N net nitrification and mineralization rates exhibited lower values in BDF than in EBF. In addition, annual soil N mineralization rate was positively correlated with litter production but negatively with C: N ratio of litter. Conclusions: Expansion of bamboo into neighboring EBF decreased litter production and quality, reduced soil N mineralization rate, and ultimately retarded N cycling. These effects should be carefully considered in the design of restoration strategies for ecosystems impacted by bamboo species. [ABSTRACT FROM AUTHOR]

• Bamboo invasion significantly increased soil pH across the subtropical forests of China. • The magnitude of soil pH increase was related to the invaded forest type. • The change in soil pH increased linearly with invasive bamboo density. Soil pH has cascading effects on terrestrial ecosystem functions by regulating the biogeochemical cycle, which can be altered by plant invasion. Bamboo invasion occurs throughout the world in both native and introduced habitats, especially in Asia. However, the effect of bamboo invasion on soil pH is still poorly understood. Here, we investigated the invasion-induced change in pH (CIP) with pairwise sampling from 215 bamboo-tree transects in subtropical China, including 203 pure bamboo forest (BF) plots, 188 mixed bamboo-tree forest (MBTF) plots and 199 non-bamboo-invaded tree forest (TF) plots. We found a significant increase in soil pH after bamboo invasion from 4.44 (±0.03) in TFs to 4.52 (±0.03) in MBTFs and 4.67 (±0.03) in BFs. The CIP was related to the invaded forest type, with the largest changes in deciduous broadleaf (0.38 ± 0.09) and mixed evergreen and deciduous broadleaf forests (0.38 ± 0.10), followed by mixed needleleaf and broadleaf forests (0.24 ± 0.05), and the smallest changes in evergreen broadleaf (0.19 ± 0.03) and needleleaf forests (0.20 ± 0.03). Further analysis showed that the CIP increased linearly with invasive bamboo density and was independent of climate factors. Overall, we provide the first evidence of a large-scale observation for bamboo invasion-induced forest soil pH increase. Our findings highlight that plant invasion should not be neglected as a driver of global change via its effects on soil pH. [ABSTRACT FROM AUTHOR]

• The whole-plant biomass equation of moso bamboo is W = 0.0646 D 2 H 0.7752 . • The relationship between below- and aboveground biomass for moso bamboo forest is M B = 1.6547 (M A) 0.6252 . • Moso bamboo forest has a high proportion of belowground biomass, with an average RS ratio of 0.37. • Biomass C storage of moso bamboo forests accounts for 1.7–2.1% of China's total forest biomass. Moso bamboo (Phyllostachys edulis) forests are widely distributed in southern China and have expanded rapidly in recent years. Although some studies have explored bamboo biomass, there are great uncertainties regarding regional- and national-scale estimations of the total biomass of bamboo forests due to a lack of systematic surveys and root biomass sampling. We investigated 322 bamboo stand plots at 48 sites across all distributed areas (15 provinces) in China in 2017–2019. We further measured the biomass of 147 individual shoots and 132 whole plants in Jiangxi Province, and determined the above- and belowground biomass in 11 sample plots using the complete harvesting method. At individual-level, the average biomass of whole-bamboo and shoot were estimated as 15.6 ± 8.3 and 12.8 ± 6.9 kg per individual, respectively. The stand mean aboveground and belowground biomass values were 60.3 ± 25.7 and 21.0 ± 5.6 Mg ha−1, with a total stand biomass of 81.4 ± 31.3 Mg ha−1 and an average root-to-shoot ratio of 0.37 ± 0.07. Using these data, combined with the 9th National Forest Inventory (NFI) dataset, we estimated that the total bamboo biomass of China was 283.0 ± 6.0 Teragrams (Tg) by using individual mean biomass and 349.5 ± 8.3 Tg by using stand mean biomass, which accounted for 1.7–2.1% of the national total forest biomass carbon pool (i.e., 8.5 Pg C). Our results provide an accurate estimation of bamboo forest biomass based on direct field measurements, and these estimates are essential to the parameterization of forest carbon models in China. [ABSTRACT FROM AUTHOR]