Ecology of Bambusa arudinacea (Retz.) Willd. growing in teak plantations of Kerala, India

Abstract

A study was undertaken to assess the contribution of bamboo to the vegetation structure, biomass productivity and nutrient cycling pattern in 15- and 20-year-old teak plantations in the Kariem-muriem Forest Range, Kerala, India. Based on the distribution pattern of bamboo colonised in these plantations, three types of site were recognised: site type A (bamboo-rich area), site type B (moderately bamboo-rich area) and site type C (bamboo-poor area). Density, basal area, number of culms per hectare, biomass, litter and net primary production of bamboo were greater in site type A than in site types B and C. While the soils of site types A and B were rich in potassium, those of site type C were rich in calcium. In addition to this, a negative correlation between above-ground biomass of bamboo and teak was recorded in site type A. In the case of teak, the rate of accumulation and the enrichment ratio of calcium were more than those of other elements. However, in bamboo, the enrichment ratio and accumulation rate of potassium were higher than in teak. The values for these parameters in bamboo were higher for potassium than for other elements. These results show that even from the nutrient conservation and cycling point of view, bamboo is a suitable species for site type A and teak is suitable for site types B and C. It is recommended that interplanting of bamboo in teak plantation, especially in areas like site types B and C, is not advisable. Instead, patch-planting may be more appropriate both to get better yield and to maintain ecosystem stability. It was also concluded that management of key elements of the ecosystem, such as potassium, is crucial for the stability of the ecosystem after disturbance or the conversion of natural forests into plantations.