World-class research. Ultimate impact.
More on impact ›

Original Research ARTICLE Provisionally accepted The full-text will be published soon. Notify me

Front. For. Glob. Change | doi: 10.3389/ffgc.2019.00065

Reducing fertilizer and avoiding herbicides in oil palm plantations - ecological and economic valuations

 Kevin Darras1*,  Marife D. Corre2,  Greta Formaglio2,  Aiyen Tjoa3, Anton Potapov4, 5,  Fabian Brambach6,  Kibrom T. Sibhatu7, Ingo Grass1,  Teja Tscharntke1,  Andres Angulo Rubiano1, 6, Damayanti Buchori8, Jochen Drescher4,  Riko Fardiansah9,  Dirk Hölscher10,  Bambang Irawan11, Thomas Kneib12,  Valentyna Krashevska4, Alena Krause4, Holger Kreft6, Kevin Li1, Mark Maraun4,  Andrea Polle13, 14,  Aisjah R. Ryadin13, 15, Katja Rembold6, 16, Stefan Scheu4, 14, Suria Tarigan17,  Alejandra Valdés-Uribe10, Supri Yadi9 and  Edzo Veldkamp2
  • 1Department of Crop Sciences, University of Göttingen, Germany
  • 2Soil Science of Tropical and Subtropical Ecosystems, Büsgen Institute, Georg-August University of Göttingen, Germany
  • 3Department of Agrotechnology, Faculty of Agriculture, Tadulako University, Indonesia
  • 4J.F. Blumenbach Institute of Zoology and Anthropology, Department of Animal Ecology, University of Göttingen, Germany
  • 5Severtsov Institute of Ecology and Evolution (RAS), Russia
  • 6Biodiversity, Macroecology and Biogeography Group, University of Göttingen, Germany
  • 7Department of Agricultural Economics and Rural Development, University of Göttingen, Germany
  • 8Department of Plant Protection, Bogor Agricultural University, Indonesia
  • 9Collaborative Research Centre, University of Jambi, Indonesia
  • 10Department of Tropical Silviculture and Forest Ecology, Faculty of Forest Sciences and Forest Ecology, University of Göttingen, Germany
  • 11Forestry Faculty, University of Jambi, Indonesia
  • 12University of Göttingen, Germany
  • 13Department of Forest Botany and Tree Physiology, Buesgen Institute, University of Göttingen, Germany
  • 14Centre of Biodiversity and Sustainable Land Use, University of Goettingen, Germany
  • 15Agriculture Faculty, Khairun University, Indonesia
  • 16Botanical Garden of the University of Bern, University of Bern, Switzerland
  • 17Department of Soil Sciences and Land Resources Management, Bogor Agriculture University, Indonesia

Oil palm plantations are intensively managed agricultural systems that increasingly dominate certain tropical regions. Oil palm monocultures have been criticized because of their reduced biodiversity compared to the forests they historically replaced, and because of their negative impact on soils, water, and climate. We experimentally test whether less intensive management schemes may enhance biodiversity and lessen detrimental effects on the environment while maintaining high yields. We compare reduced versus conventional fertilization, as well as mechanical versus chemical weed control (with herbicides) in a long-term, full-factorial, multidisciplinary experiment. We conducted the experiment in an oil palm company estate in Sumatra, Indonesia, and report the results of the first two years. We measured soil nutrients and functions, surveyed above- and below-ground organisms, tracked oil palm condition and productivity, and calculated plantation gross margins. Plants, aboveground arthropods and belowground animals were positively affected by mechanical versus chemical weed control, but we could not detect effects on birds and bats. There were no detectable negative effects of reduced fertilization or mechanical weeding on oil palm yields, fine roots, or leaf area index; however, stem growth was enhanced under mechanical weeding. Also, we could not detect detrimental effects of the reduced fertilization and mechanical weeding on soil nutrients and functions (mineral nitrogen, bulk density, and litter decomposition), but water infiltration and base saturation tended to be higher under mechanical weeding, while soil moisture and microbial biomass varied with treatment. Economic performance, measured as gross margins, was higher under reduced fertilization. There might be a delayed response of oil palm to the different management schemes applied, so results of future years may confirm whether this is a sustainable management strategy. Nevertheless, the initial effects of the experiment are encouraging to consider less intensive management practices as economically and ecologically viable options for oil palm plantations.

Keywords: fertilizer, Weeding, land use change, Oil palm, Gross margin, Biodiversity, ecosystem functions, Monoculture

Received: 22 Mar 2019; Accepted: 04 Oct 2019.

Copyright: © 2019 Darras, Corre, Formaglio, Tjoa, Potapov, Brambach, Sibhatu, Grass, Tscharntke, Angulo Rubiano, Buchori, Drescher, Fardiansah, Hölscher, Irawan, Kneib, Krashevska, Krause, Kreft, Li, Maraun, Polle, Ryadin, Rembold, Scheu, Tarigan, Valdés-Uribe, Yadi and Veldkamp. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Mx. Kevin Darras, Department of Crop Sciences, University of Göttingen, Göttingen, Lower Saxony, Germany, kdarras@gwdg.de