Intensive bamboo management shifts soil microbes toward nitrogen loss

Intensive management of moso bamboo plantations does more than boost productivity — it appears to rewire the soil nitrogen cycle in ways that could make these forests progressively less fertile, according to a new study published in Environmental Microbiome. The study used metagenomic sequencing to investigate microbial nitrogen cycling across Moso bamboo plantations under three management intensities: unmanaged stands (M0), extensively managed stands (M1), and intensively managed stands (M2).

The study’s background notes that bamboo forests deliver critical ecological and economic benefits across subtropical regions, but their productivity is frequently constrained by the availability of nitrogen. Intensive management is known to raise bamboo yields, yet its consequences for the long-term sustainability of soil nitrogen cycling had remained unclear — a gap the new work set out to address by examining both the chemical forms of soil organic nitrogen and the microbial genes that govern their transformation.

The chemical measurements told a consistent story. Both acid-hydrolyzable nitrogen and non-acid-hydrolyzable nitrogen were significantly higher in unmanaged plantations than in either managed category, while the levels of amino acid nitrogen, ammonia nitrogen, and amino sugar nitrogen declined significantly as management intensity increased. In other words, the more intensively a plantation was managed, the more its stock of organic nitrogen fractions appeared to be drawn down.

Beneath those chemical shifts lay an equally striking biological one. The microbial functional genes moved from a balanced nitrogen-cycling profile in unmanaged soils to a denitrification-dominated regime in the intensively managed stands. Specifically, the intensively managed soils showed suppressed abundance of genes for nitrogen fixation (nifH) and nitrification (amoC), alongside a marked increase in denitrification genes including narG, nirK, and nosZ.

The gene shifts tracked with changes in the microbial communities themselves. Unmanaged plantations were associated with oligotrophic Chloroflexi, organisms adapted to low-nutrient conditions. Extensively managed stands hosted versatile Proteobacteria and Nitrospirae, while the intensively managed plantations were dominated by disturbance-adapted Actinobacteria. Each management regime, it seems, selects for a distinct microbial guild, and each guild carries its own nitrogen-cycling repertoire.

The study applied distance-based redundancy analysis and Mantel tests to examine relationships between soil nitrogen fractions and other measured variables. Both confirmed that soil nitrogen fractions were significantly correlated with total organic carbon, total phosphorus, available phosphorus, nitrogen-cycling genes, and the associated microbial communities. The nitrogen chemistry, the functional genes, and the community composition moved together as a coordinated system rather than as independent responses.

Perhaps the most consequential finding came from partial least squares path analysis, which identified soil phosphorus availability as the strongest driver of soil organic nitrogen dynamics. For plantation managers, that suggests interventions aimed at nitrogen alone may miss the real lever.

The authors conclude that intensive bamboo management shifts the microbial nitrogen cycle toward denitrification, effectively converting soil organic nitrogen from a conserved pool into a more loss-prone state, with soil phosphorus availability acting as the primary driver. On that basis, they argue that maintaining long-term soil fertility in bamboo plantations will require integrated nitrogen–phosphorus management strategies rather than nitrogen-focused approaches alone.

The study, published open access on 13 October 2026, is presented as an accepted, citable version of record in progress. Its findings carry practical weight for the subtropical regions where moso bamboo is a major managed resource: if the denitrification-dominated regime proves persistent, the productivity gains that intensive management delivers in the short term may come at the cost of the soil nitrogen capital that sustains future harvests — a trade-off that integrated nutrient management will need to reconcile.

Subject of Research: How contrasting management intensities alter soil organic nitrogen fractions and microbial nitrogen-cycling genes in moso bamboo plantations

Article Title: Forest management as an intervention: responses of soil organic nitrogen and the microbially-mediated pathways in moso bamboo plantations

Article References: Zhang, X., Yang, G., Peng, Y., Li, Q., Huang, Z., Bian, F., Zhong, Z., & Wu, Z. (2026). Forest management as an intervention: responses of soil organic nitrogen and the microbially-mediated pathways in moso bamboo plantations. Environmental Microbiome. https://doi.org/10.1186/s40793-026-00960-1

Image Credits: AI Generated

DOI: 10.1186/s40793-026-00960-1

Keywords: moso bamboo, soil nitrogen, denitrification, metagenomics, soil phosphorus, microbial communities, plantation management, nitrogen fixation, nitrification, soil fertility, nitrogen-phosphorus coupling, Environmental Microbiome