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A field experiment was undertaken to identify profitable land use based on productivity, net present value, biomass and carbon stocks in litchi based land uses (LBLUs) during 1995–2015 established on degraded riverbed lands of western Himalaya, India. Results of LBLUs (20 years) revealed that LCT + LH + LPG land use produced 6.10–25.27%, 5.82–14.92% and 3.45–13.62% more fruit yield, 14.61–25.22%, 10.18–16.38% and 9.10–16.62% more total biomass, 2.95–9.51%, 0.03–4.54% and 1.60–8.26% higher carbon in soil and 6.93–14.76%, 4.60–10.03% and 6.29–13.14% more total carbon stocks as compared to sole litchi land use of 1st, 2nd and 3rd phase, respectively. Similarly, 80.39% and 78.56% more NPV, 11.74% and 19.77% higher BCR with shortest payback period (5 years) were realized in LCT + LH + LPG land use for 20 and 50 years, respectively. Sensitivity analysis also revealed that changes in discount rate will not affect its performance ranking.

Canopy management practices viz. lopping, pruning, coppicing and pollarding in trees alter branch density, height, leaf area index and rooting pattern of the trees. The present study was conducted to quantify the impact of canopy management practices and intercropping on fine and coarse roots distribution in mulberry (Morus alba). In total, six treatments comprising of three management practices (pollarding, coppicing and lopping) and two cropping situations (intercropping and without intercropping) were evaluated. Vertical and lateral distribution of fine root biomass (FRB) was recorded through sequential core method in different seasons. Coarse root distribution and biomass was studied using excavation method. Results revealed that canopy management treatments viz., coppicing and pollarding reduced the FRB as compared to lopping treatment in both intercropped and non-intercropped situation. Results also revealed that majority of the fine root biomass (67.3%) was confined in 0–15 cm soil layer. All the canopy management treatments under non-intercropped plots showed higher production rate as compared to intercropped plots. Fine root turnover rate (yr−1) was highest (0.592) in lopping treatment in non-intercropped plots whereas, the minimum turnover rate was recorded in coppicing treatment (0.331) in non-intercropped plots. Coarse root biomass was highest in case of intercropped plots in all the three canopy management treatments. Pollarding + turmeric cultivation showed the maximum root biomass followed by lopping + turmeric intercropping treatment. The main and primary roots in all the treatments accounted for > 70% biomass except for coppicng + turmeric treatment, whereas secondary and tertiary roots contributed about 40% biomass. All the treatments showed a pronounced decrease in root biomass with increasing soil depth and 75–84% of the total root biomass (main + lateral roots) was allocated in the top 30 cm of the soil profile. From the study, it can be concluded that tree management practices have direct impact on fine and coarse root distribution and should be judiciously used for avoiding competition in intercropping situation.

Psidium guajava Linnaeus., popularly known as ‘Apple of Tropics’ is one of the major fruit crops undertaken on the bouldery riverbed lands of North-Western Himalayan region. Different predictive models were fitted to establish a functional relationship between biomass and collar diameter (CD) of the tree. Out of seven different models attempted viz, Monomolecular, Logistic, Gompetz, Allometric, Rechards, Chapman and Linear, Allometric model (Y = a Xb where Y = total biomass, X = collar diameter, a and b = parameter estimates) fulfills the validation criteria to the best possible extent and is considered as best performing. Allometric model has been fitted to find the relationship between biomass of different tree components and collar diameter. All the equations indicated high correlation between biomass and collar diameter and the R2 values for the fitted functions varied from 0.89 to 0.99. The calculated t-statistic values for all the components found to be non-significant (p > 0.05) which clearly reveals the validity and reliability of the model. The developed allometric models were used to estimate the biomass and carbon stocks of P. guajava plantations of the study site. The estimated total biomass varied from 1.43 Mg ha−1 in 4 year to 40.54 Mg ha−1 in 14 year old plantation. Mitigated carbon varied from 0.26 in 4 year to 7.75 Mg ha−1 in 14 year of plantation. The total biomass carbon stocks varied from 0.48 Mg ha−1 (4 year) to 13.66 Mg ha−1 (14 year) guava plantation.

Grewia optiva Drummond is one of important agroforestry tree species grown by the farmers in the lower and mid-hills of western Himalaya. Different models viz., monomolicular, logistic, gompetz, allometric, rechards, chapman and linear were fitted to the relationship between total biomass and diameter at breast height (DBH) as independent variable. The adjusted R2 values were more than 0.924 for all the seven models implying that all models are apparently equally efficient. Out of the six non-linear models, allometric model (Y = a × DBH b ) fulfils the validation criterion to the best possible extent and is thus considered as best performing. Biomass in different tree components was fitted to allometric models using DBH as explanatory variable, the adjusted R2 for fitted functions varied from 0.872 to 0.965 for different biomass components. The t values for all the components were found non-significant (p > 0.05), thereby indicating that model is valid. Using the developed model, the estimated total biomass varied from 6.62 Mg ha−1 in 4 year to 46.64 Mg ha−1 in 23 year old plantation. MAI in biomass varied from 1.66–2.05 Mg ha−1 yr−1. The total biomass carbon stocks varied from 1.99 Mg ha−1 in 4 year to 15.27 Mg ha−1 in 23 year old plantation. Rate of carbon sequestration varied from 0.63–0.81 Mg ha−1 yr−1. Carbon storage in the soil up to 30 cm soil depth varied from 25.4 to 33.6 Mg ha−1.