Evaluation the energy production potential of aggressively invasive Prosopis juliflora Sw (Fabacea): An emerging threat in the Bundala Ramsar Wetland
Abstract Prosopis juliflora is an invasive plant species rapidly expanding in the Asian and African continents. Invasion of P. juliflora in Bundala Ramsar Wetland (BRW) in Sri Lanka has created a number of biodiversity and conservation issues. This study was conducted to assess the possibility to utilize this invasive plant as a fuel source for local industries. The moisture content, wood density, ash content, volatile matter, fixed carbon content, biomass/ash ration and calorific value of P. juliflora were measured and compared with Leucaena leucocephala, which is a widely used fuelwood source in Sri Lanka and elsewhere. P. juliflora, performed better than L. leucocephala for most of these parameters. Ash content was comparatively higher in P. juliflora than that of L. leucocephala; however, biomass to ash ratio of P. juliflora was significantly lower (at 0.05 level of significance) than that of L. leucocephala, suggesting its suitability as a fuelwood source. Further, the Fuel Value Index (FVI) of P. juliflora (3,276) was slightly lower than that of L. leucocephala (3,336), a non-significant difference. P. juliflora and L. leucocephala reached Fiber Saturation Point values within drying periods of 24 and 27 days, respectively. According to our estimates of energy properties, 1 Kg of P. juliflora could be used to substitute 0.5 L of diesel and furnace oil as well as 5 kWh (5 units) of electricity. As such, we recommend harvesting P. juliflora from BRW as a potential fuelwood energy source for local industries.