Reaction of young pine stands in Krasnoyarsk forest­steppe to thinning and application of nitrogen fertilizers

Abstract

As a result of an experiment on thinning of different intensity and the application of fertilizers (carbamide, 46 % as the active ingredient) in the young stands of the Krasnoyarsk forest­steppe, formed on former agricultural land, with the initial density 30 thousand trees per ha, data were obtained on the response of cenoses to the complex treatment. Dependences of growth on the age and initial density of plantings, and on the density and dose of fertilizer were built. It is shown that on the plots with the thinning intensity of 77 and 59 % of the number of trees, after 10 years it is necessary to carry out a second thinning treatment. It has been established that the growth response to the application of fertilizers begins from the fifth year after their application. The application of fertilizers makes it possible to reduce the competition between trees for environmental resources, which allows overdense young stands to provide the maximum possible productivity up to a certain age. The results obtained can be used not only in solving forestry problems of increasing the productivity of plantations, but also to increase their carbon sequestration functions.

Keywords

• thinning
• nitrogen fertilizer
• increment
• density
• timber stock