5. CONCLUSIONS
The study revealed that stoichiometric ratios were significantly varied for different soil and plant components, and N and P stocks increased significantly, with A. nepalensis forest chronosequence. The C: N: P stoichiometry of vegetation components, soil, and microbial biomass were found to be closely interrelated, indicating that vegetation nutrient content was a critical factor directing soil, microbial biomass nutrient inputs and thus influenced their stoichiometry. Present allocations of N and P concentrations to leaves, twigs, and litter were higher than other ecosystem components, thus reflecting lower C/P and C/N ratios, which support our second hypothesis. Our results revealed that the soil and microbial C, N, and P concentrations increased along with A. nepalensis forest chronosequence due to an increase in litter inputs and its subsequent decomposition and mineralization of nutrients. The soil profile stores the highest percentage of the N and P stocks, followed by the trees. The ecosystem N-P stocks were primarily influenced by the biomass of A. nepalensis. Overall, presentA. nepalensis forest chronosequence findings reveal the importance of N-fixing species in the recovery of degraded forest ecosystems and recommend reforestation of broadleaf tree species such asQ. leucotrichophora , R. arboreum , and other associated species with A. nepalensis to rehabilitate the degraded forests.
ACKNOWLEDGMENTS
Financial support from the Department of Science and Technology (DST), New Delhi, India (SERB No: DST/IS-STAC/ CO2-SR-181/13-G), and DST PURSE is thankfully acknowledged. This research was carried out as part of the Ph.D. program of Mr. Rajendra Kr. Joshi, which was financially supported by University Grant Commission (UGC), India.
CONFLICT OF INTEREST
The authors declare no competing financial interests.
DATA AVAILABILITY STATEMENT
The data are available from the corresponding author.
ORCID
Satish Chandra Garkotihttps://orcid.org/0000-0002-7647-6473
Rajendra Kr. Joshihttp://orcid.org/0000-0002-3410-7733
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Table 1. Biomass, nitrogen, and phosphorus (kg/ha) poll in different vegetation components across six study sites in the central Himalaya. Values in mean and stander error of three different three plots (n = 3)