Rates of leaf fall and nutrient recycling of shade trees in coffee (Coffea arabica L.), cardamom (Elettaria cardamomum Maton) and black pepper (Piper nigrum L.) production systems of Mudigere, Karnataka.

摘要

The rates of leaf fall and nutrient addition by different shade trees in coffee (Coffea arabica), cardamom (Elettaria cardamomum) and black pepper (Piper nigrum) production systems were determined at Mudigere (Karnataka, India) during 2002 and 2003. Most trees shed leaves during September to December. Highest leaf shed (4214.5 g m-2 year-1) was noticed in Artocarpus integrifolia [Artocarpus heterophyllus] followed by Ficus tsjakela (3976.2 g m-2 year-1). Nitrogen concentration of the leaves varied from 0.21% (Dalbergia latifolia) to 1.89% (Albizia lebbeck); phosphorus concentration from 0.01% (Holigarna arnottiana) to 0.11% (Pongamia pinnata); and potassium concentration from 0.21% (H. arnottiana) to 1.52% (Lagerstroemia lanceolata [L. microcarpa]). In coffee production system, A. integrifolia recorded highest content of nitrogen (39.19 g m-2 year-1) while Ficus tsjakela recorded higher phosphorus (2.07 g m-2 year-1) and potassium (34.99 g m-2 year-1) contents. In cardamom production system, Erythrina indica [Erythrina variegata] recorded higher contents of nitrogen (25.72 g m-2 year-1) and phosphorus (1.62 g m-2 year-1) while L. lanceolata contained more potassium (14.11 g m-2 year-1). In black pepper production system, Michelia champaca recorded higher contents of nitrogen (31.11 g m-2 year-1), phosphorus (3.46 g m-2 year-1) and potassium (29.95 g m-2 year-1). Species that were rich in nitrogen content had lower (<30) initial C/N ratio. Lignin content varied from 17.3 to 25.3% and cellulose from 4.4 to 10.1% in various tree species..