A study on dry matter production and nutrient cycling in agroforestry systems of cardamom grown under N2-fixing Alnus and mixed tree species (non-N2-fixing) was carried out in the Sikkim Himalaya. The stand total biomass, and tiller number, basal area and biomass of cardamom crop was much higher under the influence of Alnus. Annual net primary productivity of Alnus trees was slightly higher than mixed tree species in spite of lower stand density of Alnus. The agronomic yield of cardamom increased by 2.2 times under the canopy of Alnus. Litter production and its disappearance rates were also higher in the Alnus-cardamom stand. Nitrogen and phosphorus concentrations of different components of Alnus were higher than those of mixed tree species, whereas their back translocation from leaf before abscission was lower in Alnus. The cardamom based agroforestry system under the influence of Alnus was more productive with faster rates of nutrient cycling. The poor nutrient conservation and low nutrient use efficiency of Alnus, and malleability of nutrient cycling under its influence make it an excellent association which promotes higher availability and faster cycling of nutrients
