Shifting cultivation has resulted in large-scale deforestation and forest degradation in the tropics; however the abandoned fallows are known to have high potential for carbon capture. The paper is an attempt to determine the forest recovery patterns following shifting cultivation by evaluating the tree species composition, diversity and abundance with respect to topographical factors in Manipur, India. We also used ordination analysis to understand the change in species composition with regard to environmental variables. The living woody biomass carbon of each fallow was quantified, and the factors affecting the recovery of carbon stock along an increasing fallow gradient was assessed. Our results showed that the species richness and basal area recovered relatively with time since abandonment, and the north-facing lower elevation fallow sites displayed higher species richness and stem density than those in higher elevations. Environmental variables had no impact on the regeneration of Elaeocarpus floribundus Blume and Castanopsis hystrix Hook. f. & Thomson ex A. DC. which suggests that they may be capable of effective restoration of degraded forest areas. As these species appear naturally in the forests, it would facilitate quicker rehabilitation and reinstate the soil nutrients making the soil reusable in a short term. We also found that fallow age plays a vital role in recovering above-ground biomass carbon from living woody species followed by the aspect of the site. The total living woody biomass carbon ranged from 0.98 Mg ha-1 in 5 years fallow to 142.58 Mg ha-1 in 20 years fallow. The above-ground biomass carbon recovery of the oldest fallow was 39% to 40% of the reference undisturbed forest and the estimated time for the shifting cultivation fallows to reach that of the undisturbed forest level was approximately 39 years to 41 years.

Parkia timoriana (DC.) Merr. is one of the lesser known multipurpose leguminous tree species found in North East India. Like many other legumes this species too have hard coated seeds which prevent seed germination and thus there is a need to investigate the most appropriate method to break its dormancy. Six pre treatments (tap water, gibberellic acid (GA3) @ 500 ppm, stratification, sulphuric acid @ 98%, boiling water and nicking) and two media (top of paper (TOP) and sand) were use to evaluate seed germination traits and initial growth parameters of the seedling of this tree species. Along with these pre treatments, seeds sown in TOP media and tap water gave maximum seed germination (72%) and it was followed by seeds exposed to GA₃ for 24 hours (64%) while the least seed germination was reported in seeds treated with sulphuric acid (H2SO4) for 5 minutes. Least germination time (Mean Germination Time) was reported from the seeds treated with H2SO4 for 1 minute while maximum was reported from the boiling water treatments. Under sand medium, highest germination was reported in control (66.67 %) and it was followed by boiling water treatment (58.33%) and minimum (16.67%) in seeds treated with H2SO4 for 5 minute. Seed treated with H2SO4 for 5 minutes took minimum germination time too. Interestingly, irrespective to the media, all the seedling growth parameters showed maximum response towards hormonal (GA3) treatment and minimum towards H2SO4 treatment. Significant correlations were found between all the seedling growth parameters except for collar diameter and root-shoot ratio.

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