Soil properties and carbon dynamics under commercially important bamboo species

Introduction

Soil organic carbon is a key component of soil quality because it influences nutrient availability, aggregation, water movement and the long-term capacity of soils to function as a carbon sink. Perennial vegetation systems can improve soil carbon status through continuous litter deposition, root biomass addition and reduced soil disturbance. Bamboo is particularly important in this context because of its rapid growth, high biomass turnover, extensive root-rhizome system and continuous regeneration. These characteristics can promote organic matter accumulation and nutrient recycling in the soil. Bamboo-based systems have been reported to improve soil physical properties and soil organic carbon compared with open or fallow land. Continuous additions of leaves, roots and other plant residues may increase biologically active carbon fractions, while aggregation and humification processes can promote stabilization of more persistent carbon pools. The distribution of very labile, labile, less labile and non-labile carbon fractions provides additional information on both the quantity and quality of soil organic carbon and can be integrated through indices such as the carbon pool index (CPI) and carbon management index (CMI). Commercially important bamboo species differ considerably in biomass production, litter quality, root activity and adaptation to local conditions. Consequently, their influence on soil physical and chemical properties and soil carbon dynamics may also differ. Information comparing soil properties and carbon fractions under commercially important bamboo species is limited for the subtropical conditions of the Nagpur region. Therefore, the present investigation was undertaken to evaluate the soil physical and chemical properties, available macronutrients, soil organic carbon fractions, carbon pools, carbon indices and soil carbon stock under different commercially important bamboo species.

Materials and methods

Experimental site and treatments

The investigation was conducted during 2025-26 at the AICRP on Agroforestry, Futala Farm, College of Agriculture, Nagpur, Maharashtra, India. The plantation was established during 2015-16. The experiment was laid out in a randomized block design with three replications and consisted of nine treatments, comprising eight commercially important bamboo species and fallow land. The spacing of bamboo was 5 × 5 m, and the soil was classified as Inceptisols.

Soil sampling and analysis

Representative soil samples were collected from 0-30 cm depth from the respective treatments. Samples were shade-dried, gently ground and passed through a 2-mm sieve; subsamples intended for organic carbon determination were further prepared according to the analytical requirements. Bulk density was determined by the core method (Blake et al., 1986) [1] , while saturated hydraulic conductivity was measured by the constant-head method (Richards, 1954) [2] . Soil pH and electrical conductivity were determined using standard procedures described by Jackson (1973) [3] . Organic carbon was determined by the Walkley and Black wet oxidation method (Walkley et al., 1934) [4] , and CaCO 3 was estimated following Piper (1966) [5] . Available nitrogen was estimated by the alkaline permanganate method (Subbiah et al., 1956) [6] , available phosphorus by the Olsen method (Olsen et al., 1982) [7] , and available potassium by neutral normal ammonium acetate extraction followed by flame photometry (Jackson, 1973) [3] .

Soil carbon fractions and indices

Soil organic carbon fractions were determined using the modified Walkley and Black oxidation procedure described by Chan et al.

(2001) [8] . Very labile, labile and less labile carbon fractions were determined using progressively stronger sulphuric acid concentrations, while non-labile carbon was obtained by difference from total organic carbon. Total organic carbon was determined using a TOC analyser following the procedure cited in the thesis methodology (Tiessen et al., 1993) [9] . Active carbon pool was calculated as the sum of very labile and labile carbon, whereas passive carbon pool was calculated as the sum of less labile and non-labile carbon. The lability index, carbon pool index and carbon management index were calculated according to the procedures described in the thesis methodology and relevant literature, with fallow land serving as the reference treatment for the carbon pool index and carbon management assessment.

Statistical analysis

The experiment was analysed according to the randomized block design. Treatment means were compared using the statistical procedure adopted in the thesis. Statistical significance was interpreted at the 5% probability level wherever applicable.

Results and discussion

Soil physical properties

Bulk density and hydraulic conductivity varied among bamboo species and fallow land (Table 2). Bulk density ranged from 1.28 to 1.44 Mg m -3 . The lowest value was recorded under B. nutan (T 5 ), followed by B. balcooa (1.29 Mg m -3

), whereas fallow land recorded the highest bulk density. Hydraulic conductivity ranged from 1.50 to 2.50 cm h -1 and was highest under B. nutan and lowest under fallow land. The lower bulk density and greater hydraulic conductivity under bamboo plantations indicate improved soil structure, pore continuity and water movement. These changes may be associated with continuous organic matter inputs, root activity and improved aggregation under perennial bamboo vegetation.

Soil reaction, electrical conductivity and calcium carbonate

Soil pH ranged from 7.35 to 7.50, EC from 0.164 to 0.238 dS m -1 and CaCO 3 from 3.40 to 4.80% (Table 3). The lowest pH, EC and CaCO 3 were recorded under B. nutan, whereas fallow land recorded the highest values. The comparatively lower pH and EC under bamboo species may be related to differences in organic matter accumulation, nutrient uptake and nutrient cycling. Continuous litter decomposition may also influence soil reaction through the formation of organic acids and changes in the soil solution.

Organic carbon, total organic carbon and available macronutrients

Organic carbon and total organic carbon were consistently higher under bamboo plantations than under fallow land (Table 4). Organic carbon ranged from 5.22 to 10.20 g kg -1 and total organic carbon ranged from 7.21 to 13.81 g kg -1 . B. nutan recorded the highest values for both parameters, while fallow land recorded the lowest values. The greater carbon accumulation under bamboo species can be attributed to continuous litter deposition, root turnover and organic residue inputs. Available nitrogen, phosphorus and potassium also showed higher values under bamboo plantations than under fallow land (Table 5). B. nutan recorded the highest available N (296.00 kg ha -1 ), P (20.17 kg ha -1 ) and K (274.33 kg ha -1 ), while fallow land recorded the minimum values. The improved nutrient status may be associated with continuous litter deposition, root biomass addition, microbial mineralization and nutrient recycling under bamboo vegetation.

Treatment

Total organic carbon (g kg -

Soil organic carbon fractions

The distribution of very labile carbon (VLC), labile carbon (LC), less labile carbon (LLC) and non-labile carbon (NLC) differed among the treatments (Table 6). VLC ranged from 2.72 to 5.83 g kg -1 , LC from 1.43 to 2.50 g kg -1 , LLC from 1.07 to 2.04 g kg -1 and NLC from 1.50 to 3.61 g kg -1 .

Active and passive carbon pools

Active carbon pool ranged from 4.15 to 8.18 g kg -1 and passive carbon pool from 3.05 to 5.63 g kg -1 (Table 7). B. nutan recorded the maximum active and passive carbon pools, followed closely by B. balcooa for passive carbon. The greater accumulation of active carbon under bamboo plantations indicates continuous supply of fresh organic substrates, whereas the higher passive pool indicates enhanced stabilization of carbon through aggregation and humification. Together, these results demonstrate that bamboo vegetation can improve both short-term carbon cycling and longer-term carbon storage.

Carbon indices and soil carbon stock

Carbon indices further demonstrated the improvement in soil carbon status under bamboo plantations (Table 8). The lability index ranged from 1.68 to 1.99, with the maximum value under B. brandicee. The carbon pool index ranged from 1.00 under fallow land to 1.92 under B. nutan, while the carbon management index ranged from 167.80 to 335.94. The highest CPI and CMI under B. nutan indicate greater accumulation of soil carbon and improved carbon management relative to fallow land.

Acknowledgement

AcknowledgementThe authors acknowledge the facilities and support provided by the Soil Science Section and AICRP on Agroforestry, College of Agriculture, Nagpur, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, Maharashtra, India.

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13. How to cite this article: Danish M, Raut MM, Kuchanwar OD, Raut P, Ilorkar V, Bhosale A, et al. Soil properties and carbon dynamics under commercially important bamboo species. International Journal of Agriculture and Food Science. 2026;8(9):584-588. doi: https://www.doi.org/10.33545/2664844 X.2026.v8.i9h.1920