Secondary Succession Following Slash and Burn Agriculture in North- Eastern India: II. Nutrient Cycling

Abstract

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Variations in tree community composition and structure in a fragment of tropical semideciduous forest in southeastern Brazil related to different human disturbance histories

“…The sandy oxysols of the study region are already known for being particularly sensitive to both surface and sub-surface erosion (Ross et al, 1997). The progression of forest regeneration in an area is often accompanied by the improvement of soil fertility and water storage capacity (Aweto, 1981;Toky and Ramakrishnan, 1983). However, in the present case, it is important to stress that the 40-year regeneration period was not long enough to restore the primitive soil features.…”

Bamboo dominance reduces tree regeneration in a disturbed tropical forest

“…While bamboo leaves are linear and Xat and accumulate in a compact and thick layer on the forest Xoor, especially under moist conditions, mixed-tree litter comprise tree leaves of diVerent size, shape and surface structure, and they therefore form a more open litter layer. Furthermore, bamboo leaves decompose more slowly than tree leaves, and normally contain lower nutrient concentrations compared to litter of other species growing in the same forest (Toky and Ramakrishnan 1983;Tripathi and Singh 1995;Liu et al 2000).…”

Shifting cultivation in steeply sloped regions: a review of management options and research priorities for Mizoram state, Northeast India

“…Chronosequences of three replicate fields with similar topography and slope that had been burned either 1, 10, 15 or 20 years ago were used to show that species diversity, aboveground biomass accumulation, net primary productivity and litterfall production increased as vegetation succession proceeded (Toky and Ramakrishnan 1983a). Nitrogen, phosphorus, and potassium accumulation in shoots increased correspondingly, with bamboo accounting for almost half of total plant shoot acquisition of these elements (Toky and Ramakrishnan 1983b). Unfortunately, interpretation of all the Burnihat data is constrained because only the most preliminary statistical analyses were included and so it is often difficult to determine if apparent trends between sites or over time since burning were overwhelmed by variability among replicate fields.…”