Research and development of density management map for multifunctional management of Robinia pseudoacacia plantations with different generations of management

Objective This study established a multifunctional forest density management map for Robinia pseudoacacia plantations to achieve scientific and rational management of R. pseudoacacia forests with different cultivation purposes, and provide scientific basis for yield prediction and tending management plan formulation in forest management processes.

Method The fixed and temporary sample plots of R. pseudoacacia plantations, which located in the State-Owned Lü Village Forest Farm in Luoning County, Henan Province of northern China were set up for different management generations of R. pseudoacacia. Each tree was measured, with indexes including DBH, tree height and the number of trees, and the maximum soil water capacity of fixed sample plots in the first and second generation of R. pseudoacacia forests was determined. Additionally, the carbon storage of R. pseudoacacia stands was calculated.

Result The optimum tree height growth curve of R. pseudoacacia was fitted, and the stand density management map composed of equivalent tree height lines, equivalent diameter lines, equivalent thinning density lines, maximum density lines and natural sparse line was established. Finally, the density management map of stand productivity, carbon sequestration and water conservation ability was obtained.

Conclusion In terms of height growth curve of R. pseudoacacia tree, the application of R. pseudoacacia stand density management map in yield prediction, resource inventory and thinning operation design is analyzed. According to the reliability verification results, the model obtained in this study is suitable for R. pseudoacacia plantations in the hilly area of western Henan Province of northern China.