Tropical deciduous forests are unique in terms of their geographical distribution, strong seasonality and their contribution to global carbon dynamics, but yet their carbon sequestration potential is poorly sampled. In the current study, we report the carbon balance of 65-year-old tropical dry deciduous forest in central India using the multi-year eddy covariance measurements from November 2011 to May 2019. Over the study period, the forest site was observed to be a net sink of atmospheric CO₂ with a mean annual net ecosystem productivity (NEP) of 524 (± 40; ±1 SD across different years) g C m⁻² yr⁻¹ with a 233 (±15) day growing season. The NEP was partitioned into gross primary productivity (GPP) of 3358 (± 167) g C m⁻² yr⁻¹ and annual carbon loss due to respiration and decomposition (Reco) of 2834 (± 157) g C m⁻² yr⁻¹. The ecosystem showed a strong seasonality as a source of carbon during the leaf-off season (March to June), and as a carbon sink during the rest of the year with significant sequestration during the winter season (October to December). The intra-annual analysis suggested that CO₂ flux is primarily controlled by canopy greenness with mean Reco/GPP ratio varying from 1.90 (± 0.12) to 0.79 (± 0.04) during leaf-off to leaf-on seasons. The monthly C fluxes in the growing season are found to be strongly correlated to the environmental variables rather than in the leaf-off season, while variability in monthly ecosystem respiration was better explained by air temperature during the leaf-off season than the growing season. Further, the inter-annual variability of NEP was mainly dependent on growing season length and mean annual temperature. The variations in annual GPP and Reco were directly dependent on the increase in mean annual temperature. The eddy covariance-based NEP was complemented by close independent biometric estimates, imparting confidence in our measurements. In conclusion, this tropical dry deciduous forest site is a substantial carbon sink and would add crucial information regarding carbon budgeting of tropical forests in global carbon balance models.

就其地理分布，强烈的季节性和对全球碳动态的贡献而言，热带落叶林是独一无二的，但其碳固存潜力却很少被采样。在本研究中，我们使用从2011年11月至2019年5月的多年涡度协方差测量报告了印度中部65岁的热带落叶落叶林的碳平衡。在研究期内，观察到的森林地点为大气CO ₂的净汇，平均年净生态系统生产力（NEP）为524（±40；不同年份为±1 SD）g C m ^-2 yr ^-1，生长季节为233（±15）天。NEP被划分为3358（±167）g C m ^-2 yr的总初级生产力（GPP）^-1和每年因呼吸和分解（Reco）造成的碳损失为2834（±157）g C m ^-2 yr ^-1。生态系统表现出旺盛的季节性，在休耕季节（3月至6月）是碳源，而在其余月份则作为碳汇，而在冬季（10月至12月）则大量固存。年度分析表明，CO ₂通量主要由冠层绿度控制，叶期到叶期的平均Reco / GPP比从1.90（±0.12）到0.79（±0.04）不等。发现生长季节的每月C通量与环境变量密切相关，而不是与休耕季节密切相关，而休耕季节的气温比生长季节更好地解释了每月生态系统呼吸的变化。此外，NEP的年际变化主要取决于生长季节的长度和年平均温度。年度GPP和Reco的变化直接取决于平均年气温的升高。基于涡度协方差的NEP辅以紧密的独立生物特征估计，对我们的测量结果充满信心。结论，