Shade trees and tree pruning alter throughfall and microclimate in cocoa (Theobroma cacao L.) production systems
Shade trees in agroforestry systems protect the understory cocoa from climate extremes. Shade tree pruning manages microclimatic conditions in favor of cocoa production while tree diversity is maintained. Adaptation of pruning has to consider seasonal changes in temperature and precipitation to protect the understory cocoa.
Structural characteristics of tree stands such as species diversity, tree density, and stratification can affect throughfall and microclimate. Pruning changes the canopy and may therefore modulate internal conditions.
The aim of this study is to assess the environmental growing conditions of cocoa trees.
We monitored canopy openness and the impact of stand structure on throughfall and microclimate in three cocoa production systems (monoculture, agroforestry, and successional agroforestry) and a natural regrowth in a long-term trial in Bolivia from 2013 to 2015. We further focused on the effect of annual shade tree and cocoa pruning on these variables to evaluate the potential impact of this activity.
Agroforestry systems buffered extreme climate events like temperature fluctuations compared to monocultures but reduced light and throughfall drastically. Spatial variability of throughfall and transmitted light were low under a high and closed shade tree canopy. Shade tree pruning resulted in higher canopy openness, light transmittance, and throughfall, while the buffer function of the agroforestry systems concerning temperature and humidity fluctuations was reduced.
Differences between cocoa production systems regarding throughfall and microclimate were overlain by pruning activities. Cocoa agroforestry systems are temporal dynamic systems. Pruning timing and intensity is pivotal for balancing light and water availability under seasonally varying environmental conditions to conserve micro-environments for cocoa production with less exposure to unfavorable climate.
KeywordsAgroforestry Pruning Light Cocoa Throughfall Bolivia
Many thanks are regarded to the Ecotop-team in Sara Ana and the Institute of Ecology, University Mayor San Andres (UMSA), Bolivia, for technical and logistical support. We are grateful for the comments of the reviewers that helped us to improve the manuscript.
This study was funded by a grant from Johannes-Hübner-Stiftung, Giessen, Germany, with special support by Mrs. O. Riedl-Hübner. Study plots and field assistants were provided by FiBL, Switzerland, with fundings from Biovision Foundation for Ecological Development, Coop Sustainability Fund, Liechtenstein Development Service (LED), and the Swiss Agency for Development and Cooperation (SDC).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
Declaration of ethical issues
The manuscript was not published before and is not under consideration elsewhere.
- Allen RG, Pereira LS, Raes D, Smith M (1998) Crop evapotranspiration - Guidelines forcomputing crop water requirements -FAO Irrigation and drainage paper 56, Rome, ItalyGoogle Scholar
- Beer J, Muschler R, Kass D, Somarriba E (1998) Shade management in coffee and cacao plantations. Agrofor Syst 139–164Google Scholar
- Calheiros de Miranda RA (1994) Partitioning of rainfall in a cocoa (Theobroma cacao Lour.) plantation. Hydrol Process 351–358Google Scholar
- Canty A, Ripley B (2015) boot: Bootstrap R (S-Plus) functionsGoogle Scholar
- Clough Y, Barkmann J, Juhrbandt J, Kessler M, Wanger TC, Anshary A, Buchori D, Cicuzza D, Darras K, Putra DD, Erasmi S, Pitopang R, Schmidt C, Schulze CH, Seidel D, Steffan-Dewenter I, Stenchly K, Vidal S, Weist M, Wielgoss AC, Tscharntke T (2011) Combining high biodiversity with high yields in tropical agroforests. Proc Natl Acad Sci U S A 108:8311–8316. https://doi.org/10.1073/pnas.1016799108 CrossRefPubMedPubMedCentralGoogle Scholar
- Decagon (2013) AccuPAR PAR/LAI Ceptometer Model LP-80. Operator’s Manual. Decagon Devices, Inc., Pullman, WA Version: December 13, 2013, 08:29:36Google Scholar
- Elbers J (2002) Agrarkolonisation im Alto Beni: Landschafts- und politisch-ökologische Entwicklungsforschungin einem Kolonisationsgebiet in den Tropen Boliviens. Inaugural - Dissertation, Heinrich-Heine-Universität DüsseldorfGoogle Scholar
- Frazer GW, Canham CD, Lertzman KP (1999) Gap Light Analyzer (GLA), Version 2.0: imaging software to extract canopy structure and gap light transmission indices from true-colour fisheye photographs, users manual and program documentation. Simon Fraser University, Burnaby, British Columbia, and the Institute of Ecosystem Studies, Millbrook, New York, Simon Fraser University, Burnaby, British Columbia, and the Institute of Ecosystem Studies, Millbrook, New YorkGoogle Scholar
- Gaitán L, Armbrecht I, Graefe S (2016) Throughfall and soil properties in shaded and unshaded coffee plantations and a secondary forest: a case study from southern Colombia. JARTS 117:309–321Google Scholar
- Kuznetsova A, Brockhoff PB, Bojesen Christensen RH (2016) lmerTest: tests in linear mixed effects models, Vienna, Austria. https://CRAN.R-project.org/package=lmerTest
- McLeod AI (2011) Kendall: Kendall rank correlation and Mann-Kendall trend test. https://CRAN.R-project.org/package=Kendall
- Niether W, Armengot L, Andres C, Schneider M, Gerold G (2018) Microclimate in cocoa production systems Data. V1. Zenodo [Dataset]. https://doi.org/10.5281/zenodo.1185579
- Schneider M, Andres C, Trujillo G, Alcon F, Amurrio P, Perez E, Weibel F, Milz J (2017) Cocoa and total system yields of organic and conventional agroforestry vs. monoculture systems in a long-term field trial in Bolivia. Ex Agric 53:351–374. https://doi.org/10.1017/S0014479716000417 CrossRefGoogle Scholar
- Schroth G, Krauss U, Gasparotto L, Duarte Aguilar JA, Vohland K (2000) Pests and diseases in agroforestry systems of the humid tropics. Agrofor Syst 199–241Google Scholar
- Schroth G, Fonseca GAB, Harvey CA, Gascon C, Vasconcelos H, Izac AMN (eds) (2004) Agroforestry and biodiversity conservation in tropical landscapes. Island Press, Washington D.CGoogle Scholar
- SENAMHI (2015) SISMET-Base de datos. http://www.senamhi.gob.bo/. Accessed 20 March 2017
- Siles P, Vaast P, Dreyer E, Harmand JM (2010b) Rainfall partitioning into throughfall, stemflow and interception loss in a coffee (Coffea arabica L.) monoculture compared to an agroforestry system with Inga densiflora. J Hydrol 39–48. https://doi.org/10.1016/j.jhydrol.2010.10.005 CrossRefGoogle Scholar
- Somarriba E, Cerda R, Orozco L, Cifuentes M, Dávila H, Espin T, Mavisoy H, Ávila G, Alvarado E, Poveda V, Astorga C, Say E, Deheuvels O (2013) Carbon stocks and cocoa yields in agroforestry systems of Central America. Agric Ecosyst Environ 46–57. https://doi.org/10.1016/j.agee.2013.04.013 CrossRefGoogle Scholar
- Tscharntke T, Clough Y, Bhagwat SA, Buchori D, Faust H, Hertel D, Hölscher D, Juhrbandt J, Kessler M, Perfecto I, Scherber C, Schroth G, Veldkamp E, Wanger TC (2011) Multifunctional shade-tree management in tropical agroforestry landscapes—a review. J Appl Ecol 48:619–629. https://doi.org/10.1111/j.1365-2664.2010.01939.x CrossRefGoogle Scholar
- Unece (2010) Manual on methods and criteria for harmonized sampling, assessment, monitoring and analysis of the effects of air pollution on forests: Part XIV - Sampling and Analysis of DepositionGoogle Scholar
- Wickham H (2009) ggplot2: elegant graphics for data analysis. Use R. Springer-Verlag New York, New York, NYGoogle Scholar
- Wickham H (2011) The split-apply-combine strategy for data analysis. J Stat Softw 40:1–29Google Scholar
- Wood GAR, Lass RA (2001) Cocoa, 4th ed. Tropical agriculture series. Blackwell Science, OxfordGoogle Scholar