Resource use and benefits of mixed farming approach in arecanut ecosystem in India

Abstract

An eight-year experiment studied the sustainability, profitability, interdependencies and ecosystem services of crop–livestock integration in an arecanut plantation (ABMS) in humid tropics of India during 2007–2014. Arecanut registered similar kernel yields in both sole and intercropped systems in all years. The sole Napier Bajra Hybrid (NBH) recorded significantly higher green fodder yield than intercropped NBH. There was 5–47% yield reduction in intercropped NBH in different plantations over sole NBH on unit area basis. The total standing carbon stocks were significantly higher in arecanut + fodder system (210–228 t ha−1) than arecanut sole and fodder sole. Total water use was 47 to 50% higher in arecanut sole (2340–3280 m3) compared to ABMS (1178– 1546 m3) per unit area. The contribution of livestock to total outflows was high (82 to 87%) from 2008 to 2014 except in establishment year of dairy unit (54%). On an average, organic waste recycling potential of arecanut + dairy unit was 13.7 t ha−1 and dairy unit alone contributed to 87% of the manure production. Total nutrient supply from ABMS after recycling to the system was estimated at 218 kg N, 51.8 kg P and 33 kg K that can meet N and P demand of 1.7 and 2.2 ha of arecanut, respectively. The farm gate nutrient surplus was five times higher than utilization in ABMS that enables farmers to earn higher profits. The use of hard laterite soil for livestock enterprises like dairy, fishery and fodder cultivation resulted in improved resource use efficiency and profits per unit area per unit time. Dairywas economical under all scenarios due to on-farm fodder availability throughout the year. Our main recommendations are to include livestock components in arecanut ecosystem to adapt to climate change scenario, to provide ecosystem services and to reduce ecological imbalances arising due to continuous cultivation of perennial crop.