Recycling of wastes in areca based cropping system

Continuous use of chemical fertilizers has deteriorated the soil health and made the use of organic matter essential to restore the soil health and productivity. The availability of organic matter is again a problem because of the increase in area under crop cultivation. Thus recycling of the available organic wastes from the existing gardens especially in perennial crops gets more importance. A project was initiated at Central Plantation Crops Research Institute, Regional Station, Vittal, India during 1999 in an existing areca garden with the objective to assess the biomass availability and feasibility of applying them back into the system. The main crop was arecanut and other crops in the system were cocoa, clove, coffee, banana and pepper. The areca was planted in 1965, cocoa and clove in 1983 and the other crops in 1999. There were four treatments viz., control (only organic matter recycling (OMR), 1/3 of the recommended chemical fertilizer and OMR, 2/3 of the recommended chemical fertilizer and OMR and full chemical fertilizer and OMR. The treatments were replicated five times. The wastes available from different crops were collected and they were converted into compost using earthworms. The total biomass through the waste materials from the cropping system was recorded as 9.73 t/ha/year from areca, cocoa and clove. When these materials were converted into compost using earthworms a recovery percentage of 82 was obtained. The soil was analysed for organic carbon, mineralisable nitrogen, phosphorus and potash. There was an increase in the organic carbon, phosphorus and potassium content in the soil after the application of compost. The increase was to the extent of about 30%. Thus recycling of the wastes available garden has improved the nutrient content of the soil. The yield of the crops was recorded and it was found that combination of chemical and organic sources of nutrients is the best for obtaining sustainable yield. Application of only organics did not show significant increase in the yield. All the recorded parameters showed improvement with 2/3rd of recommended chemical fertilizer and OMR. Thus in the present context of scarce availability of organic materials from external sources, recycling of the available wastes from the existing gardens especially in arecanut based cropping systems would be an important practice for sustainable agriculture.