Apsana Kafle | ALES Graduate Seminar

Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc Final Exam Seminar by Apsana Kafle. This seminar is open to the general public to attend.

MSc with Dr. Brad Pinno.

Thesis Topic: Long-Term Impacts of Commercial Thinning and Nitrogen Fertilization on Lodgepole Pine: A Two-Decade Analysis of Growth and Temporal Dynamics

Abstract:

In 2000 an experiment with two levels of commercial thinning and six levels of nitrogen fertilization was initiated in 68-year-old lodgepole pine in Alberta. We analyzed a) the effect of thinning and fertilization on growth and mortality and b) the temporal growth response to thinning using tree cores using 20 years of thinning data. Commercial thinning led to an increase in the cumulative merchantable volume and a 20% higher yield of good sawlog trees (20 cm DBH). Thinning and fertilization individually and combined increased individual tree DBH, with the greatest growth at thinned and high fertilization (400 kg/ha levels). Size of individual trees at thinning is a predictor of post-growth with smaller trees exhibiting a delayed response for the first 5 years, followed by slow growth. Medium-sized trees displayed an immediate growth but declined after 15 years. The largest trees exhibited a slower growth response, which persisted beyond 15 years.