Leaf Litter Production and Nutrient Return in Coffee (Coffea canephora) Plantations of Different Ages in Ibadan, Nigeria

This study investigates the role of leaf litter and its nutrient input on soil fertility levels in coffee plantations of different ages in Ibadan, Nigeria. Four coffee plantations of 11, 19, 24 and 51 years were selected for the study. Each plantation was divided into four blocks where leaf litter, soil and plant samples were collected and analyzed for nutrient .Results indicated that mean total leaf litter input in these plantations ranged from 2.50 - 3.5 tha-1yr-1 with a minimum in the 11 year old plantation and maximum in the 51 year plantation. Nitrogen input from leaf litter across the coffee plantations ranged from 27.60 – 60.07 kgNha-1year-1, which was insufficient to meet the nitrogen need of coffee trees. This was reflected by the low nitrogen content of soils of the coffee plantation (0.2 g/kg - 0.8 g/kg) which was below the soil critical nitrogen level of 0.9 g/kg recommended for coffee production. Phosphorus input from the leaf litter in the different plantations was also low 0.38 - 1.73 kgPha-1 as evident from the low phosphorus content of the soil 4.49 - 5.94 mg/kg. This was also reflected in the low leaf phosphorus content of 0.14 - 0.23 g/kg. The potassium content of the leaf litter was also insufficient 17- 55.8 kg Kha-1. Calcium, magnesium, iron, and zinc were sufficient. Coffee leaf litter contributes considerable amount of nutrient to natural soil fertility management of coffee plantations but this is inadequate to meet the nutrient requirement of coffee. There is therefore need for application of fertilizer to supply limiting nutrients.