PopFor: A new model for estimating poplar yields

• Published in: Biomass & bioenergy Vol. 134; p. 105470
• Main Authors: Henner, Dagmar N., Hastings, Astley, Pogson, Mark, McNamara, Niall P., Davies, Christian A., Smith, Pete
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2020
• Subjects: Bioenergy crop; Parameterisation; PopFor; Poplar; Process-based model; Yield; Poplar; Yield; PopFor; Process-based model; Parameterisation; Bioenergy crop
• ISSN: 0961-9534; 1873-2909
• DOI: 10.1016/j.biombioe.2020.105470

Lignocellulosic bioenergy crops are a potential option for climate mitigation and for meeting the targets of the Paris Agreement in Europe. The PopFor process-based model has been developed based on the earlier MiscanFor model and parameterised for poplar using data from a literature review in combination with experimental data on high performing clones Max 1, 3, 4 for extensively and intensively managed sites in Germany. PopFor needs comparatively few input data to provide accurate estimates of biomass yield. The parameters found allowed a good match to measured values. The best fit for bud emergence is 81 °days (base 5), with leaf emergence at 463 °days (base 5) and the temperature at which photosynthesis slows is 28 °C. Maximum radiation use efficiency was set to 2.9 gMJ−1. The air temperature threshold that kills crop was set at −37 °C with the number of days below this threshold that kills the crop set at 90 days. 30 days below wiltpoint was set as a threshold that kills the crop from drought. It was found that plant available water was the key explanatory variable in predicting yield and access to groundwater explained 97% of the yield variation between the sites. The results show that the model estimates the yield of poplar after the establishment phase with a mean difference of 0.27 DM t ha−1 y−1 (r2 0.99, n29, F = 4.18, p < 0.05 with RMSE = 19.68%). PopFor was shown to be an effective model for predicting yields under different soil conditions. [Display omitted] •New poplar model for predicting yield estimates on a local or larger scale.•PopFor needs only soil and weather data, no diameter or stem measurements.•PopFor accurately modelled yield for 2nd rotation and intensively managed 1st rotation poplar coppice.•PopFor parameters are widely applicable.•PopFor is a suitable tool for defining the most suitable areas for poplar bioenergy.